Comprehensive Computational Investigation of the Porphyrin-Based COF as a Nanocarrier for Delivering Anti-Cancer Drugs: A Combined MD Simulation and DFT Calculation.

As nanomaterials have gained prominence in drug delivery technology, exploring their feasibility through computational methods is beneficial before practical tests. In this study, we aim to evaluate the capability of the porphyrin-based covalent organic framework COF-366 as a nanocarrier for two anticancer drugs, irinotecan (IRI) and doxorubicin (DOX). The optimal binding conformation of the drug molecules on the COF surface was predicted by using molecular docking. Subsequently, molecular dynamic simulation (MD) was performed to assess the adsorption mechanism of drug molecules on the COF in the aqueous environment. The free energy of adsorption for DOX and IRI was estimated to be -20.07 and -23.89 kcal/mol, respectively. The adsorption of both drugs on the COF surface is mainly influenced by the π-π interaction. Furthermore, density functional theory (DFT) calculation, natural bond orbital (NBO), and quantum theory of atoms in molecules (QTAIM) analyses were employed to investigate the structural stability of Drug@COF complexes and gain a detailed understanding of the interaction between them at the molecular level. Based on DFT results, it was found that in addition to π-π interaction, the bis-piperidine-phenylene interaction affects the adsorption of IRI on the COF surface. Moreover, the diffusion behavior of the drug molecule inside the COF pore was simulated using a ten-layer COF. Based on the mean square displacement analysis, the diffusion coefficients of DOX and IRI within the COF pore were calculated to be 108 and 97 um2/s, respectively. This computational study sheds light on how different types of interactions between the drug molecule and COF affect the adsorption and diffusion process. Our findings validated that the porphyrin-based COF-366 can serve as a nanobased platform for delivering DOX and IRI.

Theoretical Spectroscopic Study of Normal Raman and Charge Transfer Surface-Enhanced Raman Scattering (SERS) Spectra of the Adsorbed l- and d-Cysteine on the Chiral Au34 and Ag4@Au30 Nanoclusters: Chirality Discrimination.

In this work, the discrimination of the enantiomers of cysteine (l- and d-CYS) using the chiral Au34 and Ag4@Au30 clusters was theoretically investigated in the gas phase and water. Two modes were considered for the interaction of each enantiomer with the clusters (via only its S atom or its S atom and NH2 group, simultaneously). The interaction energy (Eint) and adsorption energy (Ead) for the complexation of each enantiomer with the clusters for each interaction mode were calculated. Considering the calculated interaction energies, the interaction of d-CYS with Au34 is stronger than that of l-CYS with the same cluster. Also, it was observed that the substitution of the Au4 core of the Au34 cluster with the Ag4 cluster caused the increase of the interaction energy of l-CYS with the Ag4@Au30 cluster compared to the Au34 cluster, while the reverse trend was observed for d-CYS. Quantum theory of atoms in molecules (QTAIM) analysis was employed to calculate the interaction paths and their related bond critical points (BCPs) between the CYS enantiomers and the clusters to explain the difference between the interaction energy of the enantiomers with the clusters. The IR, normal Raman (NR), and surface-enhanced Raman scattering (SERS) spectra of the enantiomers interacting with the Au34 and Ag4@Au30 clusters were calculated, and the discrimination between l-CYS and d-CYS using the calculated spectra was explained. It was found that the discrimination of the enantiomers based on their interaction with the clusters is controlled by the charge transfer between the enantiomers and the clusters.

Clinical application of biomaterials in orbital implants: a systematic review.

PURPOSE: Various materials have been proposed for reconstructing orbital fractures. The materials used must meet certain criteria to ensure their suitability for restoring the structure and function of the organ. These criteria include biocompatibility, ease of application, non-toxicity, hypo-allergenicity, and non-carcinogenicity. In this study, we systematically reviewed the studies regarding the biomaterials in orbital implants and their clinical application. METHODS: A comprehensive search across various databases, including PubMed, Scopus, EMBASE, Cochrane Library, and Web of Science, was conducted until April 10th, 2023. After retrieving the search results and eliminating duplicates, final studies were included after screening through defined criteria. Human and animal studies assessing the clinical application of biomaterials in orbital implants were included. The quality of the case series and controlled intervention studies were evaluated using the NIH tool, and for animal studies, the risk of bias was assessed using SYRCLE's tool. RESULTS: Seventeen studies were included according to defined criteria. These studies aimed to explore the clinical application of biomaterials and examine the associated complications in orbital implants. CONCLUSION: We found that using biomaterials did not result in elevated intraocular pressure (IOP). However, we did observe certain complications, with infection, residual diplopia, and enophthalmos being the most frequently reported issues.

Charge Transfer Surface-Enhanced Raman and Absorption Spectra of the Zwitterionic Form of Cysteine Adsorbed on M@Au12 (M = Au, Ag, Pt, and Pd) Nanoclusters.

The effect of the core atom type of the M@Au12 nanocluster (M = Au, Ag, Pt, and Pd) on the normal (NR) and charge-transfer surface-enhanced Raman spectroscopy (CT-SERS) of the zwitterion form of l-cysteine (ZWCYS) adsorbed on two different sites (D1 and D2) of the nanocluster is investigated separately in the gas phase and water. Because SERS requires the calculation of the absorption spectrum, the effect of the core atom type on the absorption spectrum of M@Au12 and its complex with the ZWCYS has also been investigated. The vibrational bands that show the intensity enhancement in the CT-SERS of the ZWCYS interacting with the D1 site of M@Au12 nanocluster in water are O─C═O asymmetric stretching (M = Au and Ag), NH2 bending (M = Ag), S-H stretching (M = Ag, Pt, and Pd), CH2 bending (M = Pt), and CH2 symmetric stretching (M = Pt and Pd). The ZWCYS at the D2 site of the M@Au12 nanocluster in water exhibits intensity enhancement for O─C═O asymmetric stretching (M = Pt), NH3 wagging (M = Au), and S-H stretching (M = Pd). The intensity of the vibrational bands of ZWCYS does not increase for M = Ag but decreases for O─C═O asymmetric stretching, S-H stretching, CH2 symmetric stretching, CH2 asymmetric stretching, and especially NH2 symmetric stretching.

Orbital histiocytosis and fibrohistiocytosis: the clinicopathological characteristics of 117 patients, over a decade of experience.

PURPOSE: To describe the clinicopathological features of a large cohort of patients with orbital histiocytoses and fibrohistiocytosis, such as Langerhans cell histiocytosis (LCH) and non-LCH disorders, and correlate patients' clinical characteristics with their pathological diagnosis. METHODS: In this retrospective study, medical records of patients presenting to Farabi Eye Hospital, a tertiary eye care center in Tehran, Iran, from 2010 until 2022, were reviewed. Patients' demographics, chief complaint, location and laterality of the tumor, best-corrected visual acuity, presence of bone erosion on imaging, and their pathological diagnosis were retrieved. Excisional biopsy was performed and evaluated through light microscopy and immunohistochemistry study for their respective markers, including CD1a, CD68, CD207, and S100. RESULTS: A total of 117 patients with 11 pathological subtypes of histiocytoses and fibrohistiocyosis were identified, with 56.4% male and 43.6% female patients. The mean age at presentation was 23.4 years (range 1.5 months-73 years). Swelling and palpable mass were the most common chief complaints. LCH was the most common pathology (32.5%), followed by juvenile xanthogranuloma (26.5%) and adult xanthogranuloma (21.4%). Age, lesion location, and bone erosion had a statistically significant difference among the various diagnosed subtypes. CONCLUSIONS: Histiocytoses and fibrohistiocytosis are diverse and rare disorders potentially involving multiple organ systems. Ophthalmic manifestations of these diseases are even more uncommon. We reviewed their orbital presentation along with their respective histopathological findings. Our results also suggested that an orbital CT scan can be of diagnostic value to discriminate LCH from other histiocytic pathologies.

Long-Term Impact of the COVID-19 Associated AKI: The Relationship between Kidney Recovery and Mortality in a 10-Month Follow-Up Cohort Study.

INTRODUCTION: Coronavirus-2019 disease (COVID-19)-associated acute kidney injury (AKI) and its short and mid-term effect on kidney has been well established in the previous literature, indicating a high number of AKI in hospitalized patients associated with high rates of mortality, followed by high rates of unresolved kidney injury at the time of discharge. However, the long-term impact of AKI and its resulting lack of recovery at the time of discharge has not been investigated. Herein, we sought to explore the possible relationship between AKI and unresolved kidney injury and post-discharge mortality. METHOD: In this cohort study, patients hospitalized with COVID-19 who survived until discharge were followed for a median of 9.6 months. AKI during hospitalization based on the staging according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria and kidney injury status at discharge and other comorbidities and mortality during the follow-up period were recorded. The desired association was investigated using Cox proportional hazards regression after adjustment for potential confounders. RESULT: Among 1,017 discharged patients, 298 patients (29.3%) experienced AKI during hospitalization according to KDIGO criteria, of whom 178 patients (59.7%) were diagnosed with unresolved kidney injury at the time of discharge. After adjusting for potential confounders, Cox regression indicated that AKI stage 3 (hazard ratio (HR): 4.56, 95% confidence interval (CI): 1.89-10.99, p = 0.001) and unresolved kidney injury at the time of discharge (HR: 2.09, 95% CI: 1.18-3.73, p = 0.011) were significantly associated with mortality during the post-discharge period. Additionally, Kaplan-Meier curves for overall survival indicated an increased risk of mortality in patients with stage 2, stage 3 AKI, and unresolved kidney injury at the time of discharge (p < 0.001). CONCLUSION: Overall, it was shown that patients with COVID-19 who develop AKI, mainly stage 2 and 3, and patients with unresolved kidney injury at the time of discharge, were at an increased risk of mortality, even after hospitalization for an extended period of time.

Differences in the 2020 ESC Versus 2015 ESC and 2014 ACC/AHA Guidelines on the Management of Acute Coronary Syndromes in Patients Presenting Without Persistent ST-Segment Elevation.

PURPOSE OF REVIEW: We assessed the differences in the 2020 European Society of Cardiology (ESC) versus 2015 ESC and 2014 American College of Cardiology (ACC) guidelines on the management of non-ST-segment elevation acute coronary syndromes (NSTE-ACS). RECENT FINDINGS: The recent publication of the 2020 ESC has provided a comprehensive series of recommendations on diagnosis and management of patients presenting with NSTE-ACS. However, there are discrepancies between the 2020 ESC versus 2015 ESC and 2014 ACC guidelines, creating uncertainty among clinicians in routine practices. Our investigation provides insights into several domains, including diagnosis, risk stratification, pharmacological treatments, invasive treatment, and special populations. Overall, it seems that the 2020 version of the ESC guideline for the management of NSTE-ACS provides the most evidence-based recommendations for clinicians; although due to the lack of validated investigation across some of the proposed recommendations, further longitudinal multicenter studies are warranted to address the current questions. Diagnostic algorithm in NSTE-ACS. ABBREVIATIONS: ACC = American College of Cardiology; CABG = coronary artery bypass grafting; CCTA = coronary computed tomography angiography; CMR = cardiac magnetic resonance; CS = cardiogenic shock; ECG = electrocardiography; eGFR = estimated glomerular filtration rate; ESC = European Society of Cardiology; GRACE = Global Registry of Acute Coronary Events; HF = heart failure; LVEF = left ventricular ejection fraction; MPI = myocardial perfusion imaging; MR = mitral regurgitation; NSTE-ACS = non-ST-segment elevation acute coronary syndromes; PCI = percutaneous coronary intervention; TIMI = thrombolysis in myocardial infarction.

The Risk Factors and Clinical Outcomes Associated with Acute Kidney Injury in Patients with COVID-19: Data from a Large Cohort in Iran.

INTRODUCTION: Kidney involvement, ranging from mild hematuria and proteinuria to acute kidney injury (AKI) in patients with coronavirus disease-2019 (COVID-19), is a recent finding with various incidence rates reported among hospitalized patients with COVID-19. Given the various AKI rates and their associated risk factors, lack of AKI recovery in the majority of patients hospitalized with COVID-19, and limited data regarding AKI in patients with COVID-19 in Iran, we aim to investigate the potential risk factors for AKI development and its incidence in patients hospitalized with COVID-19. METHODS: In this retrospective cohort study, we enrolled adult patients referred to the Sina Hospital, Iran, from February 20 to May 14, 2020, with either a positive PCR test or a highly susceptible chest computed tomography features consistent with COVID-19 diagnosis. AKI was defined according to the kidney disease improving global outcomes criteria, and patients were stratified based on their AKI staging. We evaluated the risk indicators associated with AKI during hospitalization besides in-hospital outcomes and recovery rate at the time of discharge. RESULTS: We evaluated 516 patients with a mean age of 57.6 ± 16.1 years and a male-to-female ratio of 1.69 who were admitted with the COVID-19 diagnosis. AKI development was observed among 194 (37.6%) patients, comprising 61.9% patients in stage 1, 18.0% in stage 2, and 20.1% in stage 3. Out of all patients, AKI occurred in 58 (11.2%) patients during the hospital course, and 136 (26.3%) patients arrived with AKI upon admission. AKI development was positively associated with all of the in-hospital outcomes, including intensive care unit admissions, need for invasive ventilation, acute respiratory distress syndrome (ARDS), acute cardiac injury, acute liver injury, multiorgan damage, and mortality. Patients with stage 3 AKI showed a significantly higher mortality rate, ARDS, and need for invasive ventilation than other stages. After multivariable analysis, male sex (odds ratio [OR]: 11.27), chronic kidney disease (CKD) (OR: 6.89), history of hypertension (OR: 1.69), disease severity (OR: 2.27), and high urea levels (OR: 1.04) on admission were independent risk indicators of AKI development. Among 117 (28.1%) patients who experienced AKI and survived, only 33 (28.2%) patients made a recovery from the AKI, and 84 (71.8%) patients did not exhibit full recovery at the time of discharge. DISCUSSION/CONCLUSION: We found that male sex, history of CKD, hypertension, disease severity, and high serum urea were independent risk factors associated with AKI in patients with COVID-19. Also, higher stages of AKI were associated with increased risk of mortality and in-hospital complications. Our results indicate a necessity for more precise care and monitoring for AKI during hospitalization in patients with COVID-19, and lack of AKI recovery at the time of discharge is a common complication in such patients.

Humidity Effect on the Drift Times of the Reactant Ions in Ion Mobility Spectrometry.

The effect of moisture content on the drift times of NH4+ and H3O+ reactant ions at different temperatures was experimentally and theoretically studied using an ion mobility spectrometer (IMS). The peak positions of the ions shifted to higher drift times as the humidity of the drift gas increased. The peak displacements were attributed to the consecutive formation of hydrated ion clusters, RI+(H2O)n. Using chemical equilibrium relations and thermodynamic data derived from DFT calculation, a model was proposed to formulate the change in the drift times as 1/td = 1/tdΘ - ßT log[H2O], where ß is a constant and T is temperature. [H2O] is the concentration of water in ppm and, tdΘ is the drift time at the standard condition of [H2O] = 1 ppm. The proposed equation perfectly predicted the change in the drift times of the reactant ions as a function of the moisture in the drift gas. Accordingly, standard mobility, K = KΘ - γT ln[H2O], was defined, which is independent of the moisture level of the drift gas and reflects the chemical reactivity. In this work, it is proposed to correct the reported reduced mobilities for the moisture to a standard condition of 1 ppm water concentration, in a similar manner to the corrections to the standard temperature and pressure of 273 K and 760 mbar, respectively. Finally, the likelihood that different hydrates forms of the reactant ion exist is discussed based on the entropy concept.

Immobilization of gold nanoparticles on folate-conjugated dendritic mesoporous silica-coated reduced graphene oxide nanosheets: a new nanoplatform for curcumin pH-controlled and targeted delivery.

In the present study, a new sandwich-like nanocomposite as a multifunctional smart nanocarrier for curcumin (Cur) targeted delivery and cell imaging was prepared by immobilization of gold nanoparticles on folic acid-modified dendritic mesoporous silica-coated reduced graphene oxide nanosheets (AuNPs@GFMS). The physical and chemical properties of the nanocomposite were investigated by atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-Vis, field-emission scanning electron microscopy (FE-SEM), Fourier transformation infrared (FT-IR), and Brunauer-Emmett-Teller (BET) surface area analysis. The nanocarrier exhibits a number of interesting properties, including good biocompatibility, biodegradability, and suitable surface area, which results in high drug loading capacity. In addition, this new drug delivery system showed sustained-release and pH-responsive properties. The in vitro cytotoxicity test of the free curcumin, free nanocarrier (AuNPs@GFMS), curcumin-loaded folate-conjugated nanocarriers (Cur-AuNPs@GFMS), and curcumin-loaded nanocarriers without folate-conjugation (Cur-AuNPs@GAMS) against two human cancer cell lines, including MCF-7 (human breast carcinoma cell lines) and A549 (human lung carcinoma cell lines) demonstrated that the therapeutic efficacy of Cur-AuNPs@GFMS is significantly greater than those of other compounds because the cancerous cells can uptake the folate-conjugated drug nanocarrier via a receptor-mediated mechanism. Fluorescence microscopic images and different staining techniques were also used to visualize the cellular uptake, anticancer activity, specific targeting ability, and photothermal potency of Cur-AuNPs@GFMS toward the MCF-7 cancer cells. The obtained results proved that the proposed system, Cur-AuNPs@GFMS, can be used as a potent anticancer agent in targeted cancer therapies for breast cancer.

Urea changes oocyte competence and gene expression in resultant bovine embryo in vitro.

SummaryNutrition influences the microenvironment in the proximity of oocyte and affects early embryonic development. Elevated blood urea nitrogen, even in healthy dairy cows, is associated with reduced fertility and there is high correlation between blood urea levels and follicular fluid urea levels. Using a docking calculation (in silico), urea showed a favorable binding activity towards the ZP-N domain of ZP3, that of ZP2, and towards the predicted full-length sperm receptor ZP3. Supplementation of oocyte maturation medium with nutrition-related levels of urea (20 or 40 mg/dl as seen in healthy dairy cows fed on low or high dietary protein, respectively) dose-dependently increased: (i) the proportion of oocytes that remained uncleaved; and (ii) oocyte degeneration; and reduced cleavage, blastocyst and hatching rates. High levels of urea induced shrinkage in oocytes, visualised using scanning electron microscopy. Urea downregulated NANOG while dose-dependently upregulating OCT4, DNMT1, and BCL2 expression. Urea at 20 mg/dl induced BAX expression. Using mathematical modelling, the rate of oocyte degeneration was sensitive to urea levels; while cleavage, blastocyst and hatching rates exhibited negative sensitivity. The present data imply a novel role for urea in reducing oocyte competence and changing gene expression in the resultant embryos.

Perrhenate-Catalyzed Deoxydehydration of a Vicinal Diol: A Comparative Density Functional Theory Study.

Oxo-rhenium compounds, such as perrhenate salts, have demonstrated preferable activity in catalyzing the deoxydehydration (DODH) reaction in the presence of reductants. Here, the first computational details of the reported DODH mechanisms are presented using the density functional theory (DFT) (M06/6-311+G(d,p)/LANL2DZ) to investigate the conversion of a vicinal diol into the corresponding alkene by ReO4- as a catalyst. The DFT studies were carried out to evaluate the DODH mechanisms, from the energy point of view, for the conversion of phenyl-1,2-ethanediol to styrene by perrhenate anion in the presence of PPh3 as a reductant through a detailed comparison of two potential pathways including pathway A and pathway B. Pathway A includes the sequence of condensation of oxo-Re(VII) with diol before the reduction of Re(VII) to Re(V), whereas pathway B involves the reduction of oxo-Re(VII) to oxo-Re(V) before the condensation process. In pathway B, two basic routes (B1 and B2) are possible, which can take place through different reaction steps, including the extrusion of alkene from Re(V)-diolate in route B1, and the second reduction of the Re(V)-diolate by reductant and then the extrusion of alkene from the Re(III)-diolate intermediate in route B2. The intermediates and the Gibbs free energy changes, including ΔG°g and ΔG°sol, have been calculated for alternative pathways (A and B) in the gas and solvent (chlorobenzene and methanol) phases and compared to each other. In addition, the transition states and the activation energy barriers for two pathways (A and B) in the gas phase and in chlorobenzene have been calculated. The key transition states include the nucleophilic attack of PPh3 on an Re═O bond, the dissociation of OPPh3 from the rhenium moiety, the transfer of an H atom of diol to the oxo ligand in an oxo-Re bond through the condensation step, and the extrusion of styrene from the Re-diolate complexes. The DFT results indicate that the DODH reaction is thermodynamically feasible through both pathways (A and B). However, the calculations reveal that the perrhenate-catalyzed DODH reaction through pathway A has the lowest overall activation barrier energy among the DODH mechanism routes.

A simple method for estimating the absolute solvation free energy of monovalent ions in different solvents.

The solvation Gibbs free energies (SGFE) of 39 ions were estimated in protic and aprotic solvents including methanol, ethanol, N,N-dimethylformamide (DMF) and acetonitrile (ACN) using a proposed approach. In this method, the error of the applied computational method, used for estimating the SGFE of a specific ion in water and dimethyl sulfoxide (DMSO) solvents, was used as a reference value to correct the calculated SGFE of the ion in other protic and aprotic solvents, respectively. The estimated values of SGFE of ions, obtained in this work, show good agreement with those obtained using the other methods reported in literature. New correlation equations were also proposed for correlating the estimated values of SGFE of ions in a specific solvent to the corresponding values in water and DMSO for protic and aprotic solvent. By using the proposed method in this work, it is possible to estimate the values of SGFE of ions in the solvents that there are no experimental and theoretical reports on them in literature provided that the appropriate and correct reference solvent is selected. Typically, this method was applied on two most popular solvents in organic chemistry including acetone and 1-propanol to estimate the SGFE of the considered ions in them for the first time.

Theoretical investigation of the borazine-melamine polymer as a novel candidate for hydrogen storage applications.

Ab initio calculations and molecular dynamic simulation were employed to study the interaction of molecular hydrogen with the borazine-melamine polymer (BMP) in order to explore its potential for hydrogen storage applications. The calculations were performed using the long range corrected version of density functional theory, the Coulomb-attenuating method (CAM-B3LYP) and the second order Møller-Plesset perturbation theory (MP2). The results showed that the average adsorption energy per hydrogen is about -0.7 and -0.3 kcal mol(-1) at the MP2/6-311+G(d,p) and CAMB3LYP/6-311+G(d,p) levels of theory, respectively. The adsorption energies were corrected for the basis set superposition error (BSSE) by the counterpoise method. It was found that the hydrogen storage capacity of the BMP is about 6.49 wt%, which is close to the values reported for the other selected materials for the hydrogen storage in the literature. The maximum number of hydrogen molecules, which were adsorbed by the BMP building block, is about ten. Molecular dynamic simulation was performed to assess the potential of BMP for hydrogen storage.

Effect of hydration on the kinetics of proton-bound dimer formation: experimental and theoretical study.

A kinetic study was performed on the proton-bound dimer formation of cyclopentanone, cyclohexanone, and cycloheptanone at atmospheric pressure with ion mobility spectrometry (IMS) at the temperature range of 30 to 70 °C. Measured rate constants were in the range of 9.5 × 10(-11) to 4.5 × 10(-10) cm(3) s(-1). Rate constants were also calculated using average dipole orientation (ADO) theory employing density functional theory (DFT). Calculated rate constants were in the range of 1.0-5.5 × 10(-9) cm(3) s(-1). The difference between experimental and calculated rate constants was interpreted based on the hydration of the protonated monomers so that water molecules were replaced with a neutral monomer molecule in the process of dimer formation. This process requires activation energy for the formation of dimer and consequently reduces the rate constants. To verify our hypothesis, an effective rate constant (keff) was introduced, which accounted for the energetically activated water-monomer replacement in the dimer formation reactions. A good agreement was observed between the experimental rate constants and calculated keff, confirming the validity of the proposed model in explaining the kinetics of dimer formation in atmospheric pressure.

Intermolecular hydrogen bonding in DNA base pairs interacting with different numbers of bare and hydrated Li+: NBO, QTAIM, and computational spectroscopic studies.

In this study, the effect of different numbers of Li+ interacting with various sites of DNA base pairs (adenine-thymine (AT) and cytosine-guanine (GC)) on the base pair structures, the strength of hydrogen bonding between the bases, and spectroscopic properties (IR and absorption spectra) of the base pairs was investigated. Two quantum computational analyses, the natural bonding orbitals (NBO) and the quantum theory of atoms in molecules (QTAIM), were used to follow the change in the strength of hydrogen bonds between the bases in each pair. The type of base pair's site interacting with Li+ showed different effects on the change in the strength of the hydrogen bonds between the bases. The IR and absorption spectra of the lithiated base pairs were calculated and compared with those of bare base pairs. This comparison provided the changes in the spectra as a fingerprint for the structural identification of different lithiated base pairs. Also, the determination of the change in the strength of hydrogen bonds in the lithiated base pairs compared to their bare base pairs. In the other part of this study, the effect of the hydration of the attached Li+ in the structure of lithiated base pairs on the strength of their hydrogen bonds and spectra was investigated.

Feasibility of qualitative identification of some metal elements in rice grains using laser desorption ionization-time of flight mass spectrometry.

Rice is one of the popular foods in the world, and the identification and measurement of the concentration of metal elements in therein is necessary for food safety. To this end, this work investigated the feasibility of using laser desorption ionization time-of-flight mass spectrometry (LDI-TOF-MS) for the qualitative identification of metal elements present in rice. The effect of different sample preparation methods (solvation of rice powder in water, acid digestion, and rice tablet) and laser wavelength on the mass spectral pattern of rice was investigated. Based on the experimental results, LDI-TOF-MS proves to be a reliable method for the qualitative identification of the metal elements in rice. It was determined that the rice sample prepared as a tablet and using visible laser radiation, are the most suitable choice for the identification of metallic elements using LDI-TOF-MS. The mass spectrum of rice was experimentally modeled using starch and theoretically simulated.

Hemicentral retinal vein occlusion in a patient with a history of coronavirus disease 2019 infection: a case report and review of the literature.

BACKGROUND: Considering the various manifestations of coronavirus disease 2019 and its imperative importance in terms of the right clinical approach and early management, we sought to present a hemicentral retinal vein occlusion case, with a history of heterozygosity of methylenetetrahydrofolate reductase (MTHFR) genes and potential for clotting complications as a late manifestation of coronavirus disease 2019, and provide a brief review of reported retinal vein occlusion cases in patients with coronavirus disease 2019. CASE PRESENTATION: A 35-year-old Iranian patient presented with a visual impairment in the left eye 4 months after recovering from coronavirus disease 2019. He reported a mild blurring of vision in the same eye a few days after admission due to coronavirus disease 2019. The ophthalmic evaluation was compatible with hemicentral retinal vein occlusion. Systemic and laboratory workups were negative except for borderline protein C activity, homocysteine levels, and heterozygosity of MTHFR genes. The patient was scheduled to receive three monthly intravitreal antivascular endothelial growth factor injections. CONCLUSION: We present a case of inferior hemicentral retinal vein occlusion case with an MTHFR mutation with sequential loss of vision 4 months after coronavirus disease 2019 to make clinicians aware of the possibility of late ocular coronavirus disease 2019 manifestations.

Meta-Analysis on the Association Between Nutritional Status and Outcomes After Transcatheter Aortic Valve Implantation.

Malnutrition is a common co-morbidity among candidates for transcatheter aortic valve implantation (TAVI). This study aimed to investigate the association between nutritional status determined by objective nutritional indices and outcomes of patients who underwent TAVI. We systematically searched PubMed, Embase, Web of Science, Scopus, and Cochrane Library from inception until April 18, 2022 to identify studies examining the association of preprocedural nutritional status with post-TAVI outcomes. Malnutrition was defined by objective nutritional indices-controlling nutritional index, nutritional risk index, geriatric nutritional risk index (GNRI), and prognostic nutritional index (PNI). The primary end point was 1-year all-cause mortality. The review included 13 observational studies and 6,785 patients who underwent TAVI. Malnutrition was associated with a higher risk of 1-year all-cause mortality, as defined by either the controlling nutritional index (hazard ratio [HR] 2.70, 95% confidence interval [CI] 1.21 to 6.03, p = 0.015), GNRI (HR 1.79, 95% CI 1.09 to 2.93, p = 0.021), or PNI (HR 1.17, 95% CI 1.11 to 1.23, p <0.001). In the meta-analysis of adjusted results, lower GNRI was independently associated with higher 1-year mortality (HR 1.70, 95% CI 1.16 to 2.50, p = 0.006). Lower GNRI was associated with increased risk of acute kidney injury (relative risk [RR] 2.21, 95% CI 1.63 to 2.99, p <0.001) and 1-year cardiovascular mortality (RR 2.50, 95% CI 1.66 to 3.78, p <0.001). Lower PNI was associated with a higher risk of major vascular complications (RR 2.99, 95% CI 1.38 to 6.51, p = 0.006). In conclusion, baseline malnutrition, as assessed by objective indices, is associated with worse outcomes after TAVI. Future studies should focus on the value of nutritional assessment and interventions to improve nutritional status in patients who underwent TAVI.

A curcumin-nicotinoyl derivative and its transition metal complexes: synthesis, characterization, and in silico and in vitro biological behaviors.

Curcumin-nicotinoyl (Cur-Nic) was synthesized by the chemical modification of the curcumin structure, characterized, and used as a ligand for the synthesis of copper(II) and zinc(II) complexes. The biological activities of Cur-Nic and its metal complexes were predicted using the PASS and Swiss Target Prediction online software, respectively, and docking studies with tyrosine-protein kinase SRC were performed using the PyRx software to predict their anticancer activities. The toxicity effects of the complexes on a human breast cancer cell line (MCF-7) compared to a healthy breast cell line (MCF-10A) were investigated by the MTS assay. Although the metal complexes maintained the least toxicity against normal cells, the results indicated that compared to curcumin and Cur-Nic, the cytotoxicity toward cancer cells increased due to the complexation process. Moreover, the antibacterial evaluation of the compounds against a Gram-positive bacterium (MRSA) and a Gram-negative bacterium (E. coli) indicated that the Cu(II) complex and Cur-Nic were the best, respectively. Also, the Zn(II) complex was the most stable compound, and the Cu(II) complex was the best ROS scavenger based on the in vitro evaluation.