Pachychoroid neovasculopathy versus macular neovascularization in age-related macular degeneration with and without shallow irregular pigment epithelial detachment.

To compare the choroidal neovascular features of individuals with pachychoroid neovasculopathy (PNV) and neovascular age-related macular degeneration (nAMD) with and without shallow irregular pigment epithelial detachment (SIPED). Using optical coherence tomography angiography, the choroidal neovascular complexes of 27 patients with PNV, 34 patients with nAMD and SIPED, and 15 patients with nAMD without SIPED were analyzed with FIJI and AngioTool software. PNV compared to nAMD with SIPED had a greater vessel percentage area (P = 0.034), junction density (P = 0.045), average vessel length (P < 0.001), and fractal dimension (P < 0.001). PNV, compared to nAMD without SIPED, had a greater total vessel length (P = 0.002), total number of junctions (P < 0.001), junction density (P = 0.034), and fractal dimension (P = 0.005). nAMD with SIPED, compared to nAMD without SIPED, had greater vessel area, total number of junctions, total vessel length, and average vessel length (all P values < 0.001). Patients with nAMD plus SIPED and individuals with nAMD without SIPED have similar fractal dimension values (P = 0.703). Biomarkers of choroidal neovascular complexity, such as fractal dimension, can be used to differentiate PNV from nAMD with or without SIPED.

Wastewater purification from Rhodamine B and Gemifeloxacine by graphene oxide/pectin/ferrite nanocomposite: A novel molecular dynamics simulation for experimental contaminants removing.

In this study, the synthesized nanocomposite was evaluated novel graphene oxide/pectin/ferrite (GOPF) adsorbent to the adsorption of Rhodamine B (RhB) and Gemifloxacin (GEM) from wastewater. Theoretical studies were carried out using quantum simulation via the Forcite module in Material Studio 2017. The simulation results demonstrated RhB and GEM adsorption over other dyes and drugs. The synthesized nanocomposite was identified by BET, TGA, FT-IR, FE-SEM, XRD, VSM, and EDS. The nanocomposite's ability to effectively take RhB and GEM from an aqueous solution was checked by performing a series of experiments based on the effect of adsorbent dose, initial condensation, contact time, pH, and temperature. The nanocomposite kinetics follow a PSO. The Freundlich isotherm model was applied for maximum adsorption capacity of GEM (124.37 mg/g) and RhB (86.60 mg/g) on GOPF nanocomposite. According to the antibacterial activity test, the synthesized nanocomposite can kill bacteria 5 mm in diameter. Also, the anti-cancer test of nanocomposite was done with 75% viability in high concentrations of nanocomposite. Thus, GOPF application results are not only suitable for dyes but only satisfying for drugs. PRACTITIONER POINTS: GOPF nanocomposite was fabricated for adsorption dye and drug and characterized. The effect of different process parameters, pH, catalyst dosage, contact time, and temperature effect was surveyed. The MD simulation were investigated to adsorb various dyes and drugs. The equilibrium isotherm and adsorption kinetic follow from Freundlich and pseudo-second-order kinetics; GOPF nanocomposite was used for about six cycles. The antibacterial activity and anticancer test of GOPF nanocomposite were investigated by satisfying results.

Unplanned Reoperation following Vitreoretinal Surgery.

Purpose: To evaluate the incidence of unplanned return to the operating room following vitreoretinal surgery and assess the reasons. Methods: In this retrospective case series, medical records of all patients who underwent vitreoretinal surgery were reviewed to determine the incidence and reasons of early (<30 days postoperatively) and late (≥30 days postoperatively) unplanned reoperations after the surgery. Results: A total of 488 eyes of 468 patients with a mean age of 55.84 ± 18.23 years were included. Fourteen percent (68/488) of eyes required one or more unplanned reoperation following their primary surgery. These include 3.9% (19/488) for the early and 10.0% (49/488) for the late reoperation. The most common primary reason for baseline surgery was rhegmatogenous retinal detachment (RRD) without proliferative vitreoretinopathy (PVR, 38.2%), followed by RD with PVR (23.5%), and tractional RD (TRD, 19.1%). Unplanned reoperations were most common in RD with PVR (19.3%), RRD without PVR (17.2%), and TRD (14.4%). Overall, the most common reasons of the first unplanned reoperation were repeated RD with PVR (27.9%), repeated RD (19.1%), and the presence of silicone oil (SO) in the anterior chamber (AC) (10.3%). For early unplanned reoperations, SO in AC, postoperative endophthalmitis, and persistent hyphema were the most common causes. Repeated RD with PVR was the most prevalent cause of late unplanned reoperations (34.7%). In the multivariate analysis, preoperative best-corrected visual acuity (BCVA) was significantly lower in eyes with unplanned reoperation than in eyes without (P = 0.011). Conclusions: Unplanned reoperation following vitreoretinal surgery is not very common, and occurs mostly in the setting of PVR, RRD, and TRD. Lower preoperative BCVA may indicate an increased chance of future unplanned reoperation(s).

A reliable QSPR model for predicting drug release rate from metal-organic frameworks: a simple and robust drug delivery approach.

During the drug release process, the drug is transferred from the starting point in the drug delivery system to the surface, and then to the release medium. Metal-organic frameworks (MOFs) potentially have unique features to be utilized as promising carriers for drug delivery, due to their suitable pore size, high surface area, and structural flexibility. The loading and release of various therapeutic drugs through the MOFs are effectively accomplished due to their tunable inorganic clusters and organic ligands. Since the drug release rate percentage (RES%) is a significant concern, a quantitative structure-property relationship (QSPR) method was applied to achieve an accurate model predicting the drug release rate from MOFs. Structure-based descriptors, including the number of nitrogen and oxygen atoms, along with two other adjusted descriptors, were applied for obtaining the best multilinear regression (BMLR) model. Drug release rates from 67 MOFs were applied to provide a precise model. The coefficients of determination (R2) for the training and test sets obtained were both 0.9999. The root mean square error for prediction (RMSEP) of the RES% values for the training and test sets were 0.006 and 0.005, respectively. To examine the precision of the model, external validation was performed through a set of new observations, which demonstrated that the model works to a satisfactory degree.

Delayed-Onset Endophthalmitis after Intravitreal Aflibercept Injection.

Purpose: To describe delayed-onset infectious endophthalmitis 4 months after intravitreal aflibercept injection. Methods: An 80-year-old female was referred with signs and symptoms of clinical endophthalmitis 4 months after intravitreal injection of aflibercept for choroidal neovascularization. Noninfectious causes of panuveitis were excluded and she was diagnosed with delayed-onset postinjection infectious endophthalmitis. Vitreous and aqueous specimens were prepared and antibiotics (vancomycin and ceftazidime) were injected intravitreally. Results: Vitreous culture was positive for Staphylococcus epidermidis. During the 1st month after the antibiotic injections, symptoms and signs of the patient improved and became stable during the 6-month follow-ups. Conclusions: Delayed-onset infectious endophthalmitis can be presented following intravitreal injections. Late presentation of uveitis in postinjected eyes needs complete investigations to rule out infectious endophthalmitis as an ophthalmic emergency.

Enhanced Photocatalytic CO2 Reduction by Novel Designed Porphyrin-Based MOFs: From Accurate QSPR Model to Experimental Exploration.

A reliable quantitative structure-property relationship (QSPR) model was established for predicting the evolution rate of CO2 photoreduction over porphyrin-based metal-organic frameworks (MOFs) as photocatalysts. The determination coefficient (R 2) for both training and test sets was 0.999. The root-mean-squared error of prediction (RMSEP) obtained was 0.006 and 0.005 for training and test sets, respectively. Based on the proposed model, two porphyrin-based MOFs, Cu-PMOF and Co-PMOF, were designed, synthesized, and applied for CO2 photoreduction under UV-visible irradiation without any additional photosensitizer. The X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), and Fourier transform infrared (FTIR) measurements revealed the successful formation of the porous MOFs. The N2 adsorption isotherms at 77 K showed a high Brunauer-Emmett-Teller (BET) surface area of 932.64 and 974.06 m2·g-1 for Cu-PMOF and Co-PMOF, respectively. Theoretical and experimental results showed that HCOOH evolution rates over Cu-PMOF and Co-PMOF were (127.80, 101.62 µmol) and (130.6, 103.47 µmol), respectively. These results were robust and satisfactory.

The Efficacy of Lactocare® Synbiotic on the Clinical Symptoms in Patients with Psoriasis: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

Background: Attention to the administration of probiotics for the treatment of psoriasis has recently increased. Aim: In the present study, improvements in dermatology life quality index (DLQI), psoriasis area severity index (PASI), and visual analogue scale (VAS) scores in the psoriasis patients receiving Lactocare® probiotic were compared to psoriasis patients receiving placebo. Methods: A total of 52 psoriasis patients were included in this study and randomly divided into treatment and placebo (control) groups. The control group received topical hydrocortisone associated with placebo; in the treatment group, Lactocare® was administrated orally associated with hydrocortisone. The mean of VAS, DLQI, and PSAI scores was recorded and evaluated pretreatment and post-treatment in both groups for 3 months. The mean of the scores in the control groups was compared to the treatment group. Intragroup analysis was preformed with a comparison of the mean of these scores at baseline 4-, 8-, and 12-weeks post-treatment. Results: In the treatment group, a significant decrease was seen in PASI, VAS, and DLQI scores compared to the control group on week 12 post-treatment. Conclusion: Oral administration of Lactocare® probiotic (two times daily) associated with administration of topical hydrocortisone resulted in the improvement of PASI, DLQI, and VAS scores in the patients with psoriasis after 12 weeks of treatment. PASI reduction occurred in all patients who received probiotics.

Recent advances on biomedical applications of pectin-containing biomaterials.

There is a growing demand for biomaterials developing with novel properties for biomedical applications hence, hydrogels with 3D crosslinked polymeric structures obtained from natural polymers have been deeply inspected in this field. Pectin a unique biopolymer found in the cell walls of fruits and vegetables is extensively used in the pharmaceutical, food, and textile industries due to its ability to form a thick gel-like solution. Considering biocompatibility, biodegradability, easy gelling capability, and facile manipulation of pectin-based biomaterials; they have been thoroughly investigated for various potential biomedical applications including drug delivery, wound healing, tissue engineering, creation of implantable devices, and skin-care products.

Synthesis of a new chitosan-p-tert-butylcalix[4]arene polymer as adsorbent for toxic mercury ion.

In this paper, we have synthesized a novel chitosan-p-tert-butylcalix[4]arene polymer (CCP) as a highly efficient adsorbent for mercury ion (Hg2+) removal from water. In fact, a lower rim diamine derivative of p-tert-butylcalix[4]arene has been cross-linked with chitosan chain by carbonyl diimidazole (CDI) as the linker. CDI forms a urea linkage between calix[4]arene diamine derivative and amine groups of the chitosan polymeric chain. The structure and properties of the new polymer were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope. Also, the adsorption capacity of CCP was studied towards Hg2+ in aqueous medium by inductively coupled plasma-optical emission spectrometry. Interestingly, the results showed a considerable adsorption capacity for CCP in comparison with chitosan. Therefore, CCP can be introduced as a promising adsorbent for the elimination of Hg2+ from wastewaters. Moreover, because of the conformity of adsorption kinetic with pseudo-second-order kinetic models, it can be concluded that chemical adsorption has an important role between functional groups on CCP polymer and Hg2+ ions. In addition, according to Freundlich isotherm, the CCP surface was heterogeneous with different functional groups.

Functionalized graphene oxide nanosheets with folic acid and silk fibroin as a novel nanobiocomposite for biomedical applications.

In this paper, a novel graphene oxide-folic acid/silk fibroin (GO-FA/SF) nanobiocomposite scaffold was designed and fabricated using affordable and non-toxic materials. The GO was synthesized using the hummer method, covalently functionalized with FA, and then easily conjugated with extracted SF via the freeze-drying process. For characterization of the scaffold, several techniques were employed: Fourier-transform infrared (FT-IR), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), and thermogravimetric analysis (TGA). The cell viability method, hemolysis, and anti-biofilm assays were performed, exploring the biological capability of the nanobiocomposite. The cell viability percentages were 96.67, 96.35 and 97.23% for 24, 48, and 72 h, respectively, and its hemolytic effect was less than 10%. In addition, it was shown that this nanobiocomposite prevents the formation of Pseudomonas aeruginosa biofilm and has antibacterial activity.

Evaluation of Lactocare® Synbiotic Administration on the Serum Electrolytes and Trace Elements Levels in Psoriasis Patients: a Randomized, Double-Blind, Placebo-Controlled Clinical Trial Study.

BACKGROUND: Despite the exact etiopathogenesis of psoriasis remains unknown, the increasing or decreasing of some trace elements and oxidative stress status are considered to play a role. In this study, the effect of Lactocare® synbiotic on the serum levels of trace elements including Zn, Cu, Mg, Na, Fe, P, Ca, and K in the patients with mild to moderate psoriasis was investigated. METHODS: Sixty-four patients with mild to moderate psoriasis were included. Patients were randomly divided into treatment (n═32) and control (n═32) groups. The treatment group received Lactocare® and the control group received a placebo (two times daily for 12 weeks). Eight patients from the intervention group and 18 patients from the control group discontinued the study because of the recent COVID-19 condition. For routine trace element analysis, the blood samples were collected from all patients at the baseline as well as week 12 post-treatment. The serum was then isolated and the serum levels of trace elements including Fe, K, Ca, Mg, P, Zn, Na, and Cu were measured using an automatic electrolyte analyzer. For confirmation of the effect of Lactocare® on the alteration of serum levels of trace elements, intra-group analysis was performed at two interval times: baseline and week 12 post-treatment. RESULTS: The serum levels of K, P, and Ca in the placebo group were significantly higher than that of the treatment group at baseline. Serum levels of Zn and Ca were significantly higher in the treatment group compared to the placebo group at week 12 post-treatment. Moreover, a significantly lower serum level of K, P, and Ca in the treatment group at the baseline compared to the placebo group was compensated on week 12 post-treatment. Intra-group analysis in the treatment group showed that the serum levels of Fe, Ca, Mg, P, Zn, and Na was significantly increased at week 12 post-treatment compared to baseline levels. Whereas, intra-group analysis in the control group showed only Ca has a significant difference between baseline and week 12 post-treatment. CONCLUSION: The serum levels of Fe, Zn, P, Mg, Ca, and Na are increased significantly 12 weeks after oral administration of Lactocare® in psoriatic patients. The serum level of Fe and Cu is affected by sex at pre- and post-treatment. This study supports the concept that Lactocare® exerts beneficial effects in the gastrointestinal tract to improve mineral absorption in psoriatic patients.

Novel magnetic organic-inorganic hybrids based on aromatic polyamides and ZnFe2O4 nanoparticles with biological activity.

Magnetic nanoparticles were creatively selected as stable, inexpensive, biodegradable, facile recoverable, and functionalizable supports for a variety of synthetic and natural polymers. Herein, for the first time, aromatic polyamide was synthesized on the magnetic core of zinc iron oxide (ZnFe2O4). Terephthaloyl chloride and derivations of phenylenediamine were employed as monomers in this polymerization process. The toxicity of the synthesized hybrid at the highest concentration (1000 µg/ml) is 13.65% and on the other hand, the cell viability percentage is 86.35%. So, the prepared hybrid is biocompatible and non-toxic to Hu02 cells. Also, it has antibacterial ability against gram-positive and gram-negative bacteria. Because the results show that the minimum inhibitory concentration (MIC) of the synthesized polymer for bacteria such as Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853 is in the range of 500-1000 µg/ml. Moreover, the hemolytic effect of ZnFe2O4 based hybrid was below 9% at the concentration of 1000 µg/ml. Therefore, it is compatible with red blood cells.

Recent progress to construct calixarene-based polymers using covalent bonds: synthesis and applications.

The combination of supramolecular chemistry and polymer sciences creates a great possibility to afford calixarene-based polymers offering unique features and applications. The enhancement of calixarene's versatility in this manner has made chemists better able to achieve different objectives in host-guest chemistry. The calixarene-based polymers can be divided into covalent polymers and supramolecular polymers regarding the interactions. Although there are several studies available on the calixarene-based supramolecular polymers, there is a paucity of studies on the calixarene-based covalent polymers. In this paper, the most recent developments and applications of the calixarene-based covalent polymers in the last two decades have been reviewed. We have particularly focused on the polymers, including those where the calixarene molecules have been used as macromonomers and polymerize through covalent bonds. Moreover, covalent polymers or solid supports functionalized with calixarenes are highlighted as well.

Optimization and High Level Production of Recombinant Synthetic Streptokinase in E. coli Using Response Surface Methodology.

Streptokinase (SK) is an extracellular protein comprising 414 amino acids with considerable clinical importance as a commonly used thrombolytic agent. Due to its wide spread application and clinical importance designing more efficient SK production platforms worth investigation. In this regard, a synthetic SK gene was optimized and cloned in to pET21b plasmid for periplasmic expression. Response surface methodology was used to design a total of 20 experiments for optimization of IPTG concentration, post-induction period, and cell density of induction (OD600). The optimum levels of the selected parameters were successfully determined to be 0.28 mM for IPTG concentration, 9.889 H for post induction period, and 3.40768 for cell density (OD600). These settings result in 4.14fold increase in SK production rate of optimum expression conditions (7663 IU/mL) in comparison to the primary expression conditions (1853 IU/mL). Achieving higher yields of SK production in shake flask could lead to more cost effective industrial production of this drug which is the ultimate aim of SK production studies.

Improvement of Selenomonas ruminantium ß-xylosidase thermal stability by replacing buried free cysteines via site directed mutagenesis.

ß-xylosidase is an essential enzyme for breakdown of xylan to d-xylose. It has a significant potential application value for medicine, food, paper and pulp, and biofuel industries. Due to the negative consequences caused by buried free cysteine residues, mutational substitution of such residues is often accompanied by a notable increase in thermal stability. To characterize the role of cysteine residues in the structure, function and stability of Selenomonas ruminantium ß-d-Xylosidase (SXA), we prepared and evaluated wild-type and four cysteines- deficient SXA proteins. Buried cysteine residues were replaced with. In comparison with the wild-type, the Km values of the mutants remained relatively constant while their kcat values decreased. The C101V and C286V displayed higher thermal stability than the wild-type at 55 and 60 °C. Conformational changes of the secondary and tertiary structure as derived from circular dichroism and fluorescence spectroscopy revealed that changing a buried cysteine to a hydrophobic residue could lead to an increase in thermal stability with minimal perturbation of the wild-type protein structure. In addition to experimental methods, the stability of WT SXA and C101V and C286V mutants at 333 K was also studied by MD simulation. Our theoretical data had a good agreement with the experimental results.

Highly functionalized calix[4]arenes via multicomponent reactions: synthesis and recognition properties.

Multicomponent reactions (MCRs) include several aspects of green chemistry principles, so it is obvious that chemists in different areas are increasingly interested in providing their product by multicomponent approaches. MCRs can be very useful in supramolecular chemistry, especially to produce novel supramolecular derivatives. Therefore, there are several reports of highly-functionalized calix[4]arene derivatives obtained by MCRs instead of conventional stepwise protocols during the last decade. In this paper, we have particularly focused on the exploitation of upper rim and lower rim substituted calix[4]arenes in multicomponent approaches as a facile and convenient synthetic strategy. The value of this method lies in its operational simplicity, mild reaction conditions and structural diversity of the products. Interestingly, in most cases the products afforded by this method offer unique features and applications which are highlighted in the following sections.

Disulfide bonds elimination of endoglucanase II from Trichoderma reesei by site-directed mutagenesis to improve enzyme activity and thermal stability: An experimental and theoretical approach.

EndoglucanaseII (Cel5A) of Trichoderma reesei is widely used industrially with the high catalytic efficiency, but it is not stable high temperatures. Structural comparison with the closest thermophilic endoglucanase homolog, Cel5A from Thermoascus aurantiacus, demonstrates disulfide bond differences. Replacement of Cysteine99 with Valine and Cysteine323 with Histidine by site directed mutagenesis caused elimination of two disulfide bonds. Recombinant expression in Pichia pastoris showed the catalytic efficiency (kcat/Km) increment toward CMC for single mutant enzymes, C99V and C323H, about 1.87 and 1.3 folded respectively. This indicates that the elimination of disulfide bond in substrate binding cleft around the catalytic domain of mutant EndoglucanaseII may be increased the flexibility of protein, to form a suitable E-S complex. In direct contrast with previous studies suggesting the existence of disulfide bonds increase the protein stability, the results showed mutant endoglucanase enzymes with disulfide bond reduction have higher thermal stability. The thermal stability of C99V and C323H in 80 °C were increased 2.4 and 2.34 folded, respectively. In this project, theoretical data had a good agreement with the experimental results. Because of high enzyme activity and thermal stability, both of C99V and C323H mutant have high potential suitable for different industrial applications.

Selective reduction in glutaminase activity of l­Asparaginase by asparagine 248 to serine mutation: A combined computational and experimental effort in blood cancer treatment.

Type II l­asparaginase (l­ASNase) is an FDA approved enzyme drug with extensive applications for treatment of certain blood cancers. However, the therapeutic efficiency of this enzyme is hampered by its undesirable glutaminase activity. Given the pivotal role of this enzyme against cancer, designing engineered mutants with diminished glutaminase activity would be of great therapeutic interest. To this end, N248S mutation was selected as the potential mutation with beneficial effects. Various in silico analyses including MD simulation, molecular docking and QMMM studies were performed to assess the effects of N248S mutation on the activity of the enzyme. Thereafter, this mutation along with N248A, N248V and N248T mutations as controls were exerted in l­ASNase gene. The results from in silico analyses and experimental efforts indicated that N248S mutation is associated with the suitable l­ASNase activity, while the glutaminase activity is disturbed due to impaired interactions. It has been shown that glutamine turnover was affected much more strongly than asparagine hydrolysis. The approach of exploiting in silico tools to design mutated enzymes lead to staggering time and cost reduction. Following this strategy, we have designed a mutant l­ASNase with diminished glutaminase activity, which could be of interest for improved biomedical applications.

Monitoring and assessment of soil erosion at micro-scale and macro-scale in forests affected by fire damage in northern Iran.

Understanding the occurrence of erosion processes at large scales is very difficult without studying them at small scales. In this study, soil erosion parameters were investigated at micro-scale and macro-scale in forests in northern Iran. Surface erosion and some vegetation attributes were measured at the watershed scale in 30 parcels of land which were separated into 15 fire-affected (burned) forests and 15 original (unburned) forests adjacent to the burned sites. The soil erodibility factor and splash erosion were also determined at the micro-plot scale within each burned and unburned site. Furthermore, soil sampling and infiltration studies were carried out at 80 other sites, as well as the 30 burned and unburned sites, (a total of 110 points) to create a map of the soil erodibility factor at the regional scale. Maps of topography, rainfall, and cover-management were also determined for the study area. The maps of erosion risk and erosion risk potential were finally prepared for the study area using the Revised Universal Soil Loss Equation (RUSLE) procedure. Results indicated that destruction of the protective cover of forested areas by fire had significant effects on splash erosion and the soil erodibility factor at the micro-plot scale and also on surface erosion, erosion risk, and erosion risk potential at the watershed scale. Moreover, the results showed that correlation coefficients between different variables at the micro-plot and watershed scales were positive and significant. Finally, assessment and monitoring of the erosion maps at the regional scale showed that the central and western parts of the study area were more susceptible to erosion compared with the western regions due to more intense crop-management, greater soil erodibility, and more rainfall. The relationships between erosion parameters and the most important vegetation attributes were also used to provide models with equations that were specific to the study region. The results of this paper can be useful for better understanding erosion processes at the micro-scale and macro-scale in any region having similar vegetation attributes to the forests of northern Iran.

Diagnostic accuracy of frozen section of central nervous system lesions: a 10-year study.

OBJECTIVE: Definitive diagnosis of the central nervous system (CNS) lesions is unknown prior to histopathological examination. To determine the method and the endpoint for surgery, intraoperative evaluation of the lesion helps the surgeon. In this study, the diagnostic accuracy and pitfalls of using frozen section (FS) of CNS lesions is determined. MATERIALS & METHODS: In this retrospective study, we analyzed the results of FS and permanent diagnoses of all CNS lesions by reviewing reports from 3 general hospitals between March 2001 and March 2011. RESULTS: 273 cases were reviewed and patients with an age range from 3 to 77 years of age were considered. 166 (60.4%) had complete concordance between FS and permanent section diagnosis, 83 (30.2%) had partial concordance, and 24 cases (9.5%) were discordant. Considering the concordant and partially concordant cases, the accuracy rate was 99.5%, sensitivity was 91.4%, specificity was 99.7%, and positive and negative predictive values were 88.4% and 99.8%, respectively. CONCLUSION: Our results show high sensitivity and specificity of FS diagnosis in the evaluation of CNS lesions. A Kappa agreement score of 0.88 shows high concordance for FS results with permanent section. Pathologist's misinterpretation, small biopsy samples (not representative of the entire tumor), suboptimal slides, and inadequate information about tumor location and radiologic findings appear to be the major causes for these discrepancies indicated from our study.