The accuracy of non-contrast brain CT scan in predicting the presence of a vascular etiology in patients with primary intracranial hemorrhage

Abstract Spontaneous intraparenchymal cerebral hemorrhages (SIPH) account for 10–15% of acute strokes. Sorting these patients according to the risk of harboring an underlying vascular etiology may help selecting the patients who would mostly benefit from Multidetector CT Angiography (MDCTA). The aim of this study was to evaluate the accuracy of Non-Contrast brain CT (NCCT) in predicting possible vascular etiologies in patients with SIPH. In this retrospective study, we evaluated the NCCT of 334 patients who presented with SIPH from March 2017 to March 2021 and we looked for vascular etiologies in the CTA which was performed for these patients. We used NCCT criteria to predict the presence of any vascular etiologies in SIPH patients and proposed a scoring system based on these criteria which might predict the risk of vascular ICH (VICH score). Out of 334 evaluated patients, 9.3% had an underlying vascular etiology. Independent predictors of the vascular etiology included: age < 46 years, no history of hypertension and coagulation disorders, lobar hemorrhages, and presence of significant perilesional edema. We used these criteria and NCCT classification to create a practical scoring system to predict the risk of vascular ICH (VICH). In our study, VICH score ≥ 4 had 51.6% sensitivity and 96.4% specificity for predicting a positive MDCTA as the maximum optimal cut-off point. The VICH score seemed to be successful in predicting vascular etiologies in this retrospective cohort of 334 patients. This scoring system can be used to select patients if there are limited resources to perform CT angiography

Enhancement of adsorption efficiency of crystal violet and chlorpyrifos onto pectin hydrogel@Fe3O4-bentonite as a versatile nanoadsorbent

Abstract The magnetic mesoporous hydrogel-based nanoadsornet was prepared by adding the ex situ prepared Fe3O4 magnetic nanoparticles (MNPs) and bentonite clay into the three-dimentional (3D) cross-linked pectin hydrogel substrate for the adsorption of organophosphorus chlorpyrifos (CPF) pesticide and crystal violet (CV) organic dye. Different analytical methods were utilized to confirm the structural features. Based on the obtained data, the zeta potential of the nanoadsorbent in deionized water with a pH of 7 was − 34.1 mV, and the surface area was measured to be 68.90 m2/g. The prepared hydrogel nanoadsorbent novelty owes to possessing a reactive functional group containing a heteroatom, a porous and cross-linked structure that aids convenient contaminants molecules diffusion and interactions between the nanoadsorbent and contaminants, viz., CPF and CV. The main driving forces in the adsorption by the Pectin hydrogel@Fe3O4-bentonite adsorbent are electrostatic and hydrogen-bond interactions, which resulted in a great adsorption capacity. To determine optimum adsorption conditions, effective factors on the adsorption capacity of the CV and CPF, including solution pH, adsorbent dosage, contact time, and initial concentration of pollutants, have been experimentally investigated. Thus, in optimum conditions, i.e., contact time (20 and 15 min), pH 7 and 8, adsorbent dosage (0.005 g), initial concentration (50 mg/L), T (298 K) for CPF and CV, respectively, the CPF and CV adsorption capacity were 833.333 mg/g and 909.091 mg/g. The prepared pectin hydrogel@Fe3O4-bentonite magnetic nanoadsorbent presented high porosity, enhanced surface area, and numerous reactive sites and was prepared using inexpensive and available materials. Moreover, the Freundlich isotherm has described the adsorption procedure, and the pseudo-second-order model explained the adsorption kinetics. The prepared novel nanoadsorbent was magnetically isolated and reused for three successive adsorption–desorption runs without a specific reduction in the adsorption efficiency. Therefore, the pectin hydrogel@Fe3O4-bentonite magnetic nanoadsorbent is a promising adsorption system for eliminating organophosphorus pesticides and organic dyes due to its remarkable adsorption capacity amounts

Highly efficient remediation of chlorpyrifos and malachite green by an SBA-15 incorporated guar gum-grafted-poly (acrylic acid)/cobalt ferrite matrix for water purification

The Santa Barbara Amorphous-15-guar gum-grafted-poly (acrylic acid)/cobalt ferrite (SBA-15-GG-g-PAA/CoFe2O4) mesoporous adsorbent was prepared by graft copolymerization of acrylic acid (AA) onto guar gum (GG) in the Santa Barbara Amorphous-15 (SBA-15) substrate presence, followed by incorporating CoFe2O4 magnetic nanoparticles (MNPs). Diverse analyses were conducted to identify the prepared mesoporous adsorbent’s chemical and morphological properties, thermal resistance, magnetic characteristics, surface area, and porosity. Based on the magnetic hysteresis loops, the mesoporous adsorbent rendered ferromagnetic behavior. According to TGA, it has char yields of 72 wt% at 800 °C and superparamagnetic behavior (Ms of 3.22 emu.g−1). The crystalline structure and cubic phases of CoFe2O4 MNPs in the GG-g-PAA amorphous matrix were demonstrated by XRD. The CoFe2O4 MNP formation with partial aggregations onto smooth, nonporous, and regular surfaces of the GG was depicted by FESEM images. Also, the precisely-arranged hexagonal structure with cylindrical pores of SBA-15 was authenticated by FESEM images. Additionally, the SBA-15 substrate has increased the BET surface area of the prepared mesoporous adsorbent to 40.55 m2/g, which is higher than the composite without SBA-15 mesoporous silica. Several experimental setups were used to evaluate the effectiveness of adsorption, including pH of the medium (4–9), Adsorbent dosage (0.003–0.02 g), Interaction time (1–25 min), and Initial pollutant concentration (50–400 mg/L). Using 0.003 g of mesoporous adsorbent at 25 °C, chlorpyrifos (CPF) and malachite green (MG) had maximum adsorption capacities (Qmax) of 909.1 mg/g and 1000.0 mg/g, respectively. In this study, the Langmuir isotherm model fitted the adsorption data perfectly withRMG2 = 0.9987 andRCPF2 = 0.9994, and the pseudo-second-order model explained the adsorption kinetics with RMG2 = 0.9644 and RCPF2 = 0.9923. MG and CPF adsorption to the SBA-15-GG-g-PAA/CoFe2O4 mesoporous adsorbent was successful due to hydrogen bonds, exchange interactions, diffusion, and entrapment in the hydrogel network. In addition to the three-dimensional structure, the mesoporous adsorbent has available adsorption sites for reactive molecules. The reusability of the SBA-15-GG-g-PAA/CoFe2O4 was perused and showed that the mesoporous adsorbent can be separated efficiently and retrieved in three sequential cycles without considerable diminution in the adsorption efficiency

Carrageenan-grafted-poly(acrylamide) magnetic nanocomposite modified with graphene oxide for ciprofloxacin removal from polluted water

The κ-carrageenan-grafted-poly(acrylamide)/Fe3O4-GO (κ-car-g-PAAm@Fe3O4-GO) adsorbent was attained in three stages, utilizing grafted poly(acrylamide) (PAAm) onto κ-carrageenan (κ-car) in Fe3O4 and graphene oxide (GO) presence. Various characteristic analyses were carried out to peruse the chemical properties, morphological features, thermal stability, magnetic behavior, and porosity of the prepared nanoadsorbent. According to the results obtained from the analyses, the prepared nanoadsorbent showed superparamagnetic behavior. It rendered a semicrystalline structure by Fe3O4 presence in the amorphous matrix of the κ-car-g-PAAm. The SEM images exhibit well dispersion of the Fe3O4 magnetic nanoparticles (MNPs) and lamellar GO sheets throughout the hydrogel context. Besides, along with the GO incorporation into the structure, the BET surface area (2.361 m2/g), pore volume (0.008 cm3/g), and pore size (137.49 nm) of the κ-car-g-PAAm@Fe3O4-GO nanoadsorbent were higher than κ-car-g-PAAm@Fe3O4. The maximum adsorption capacity (Qmax) at an ambient temperature for CPFX adsorption was 1146.467 mg/g. These adsorption experiments’ data were described by the Freundlich isotherm, and the pseudo-second-order explains the adsorption kinetics well. The retrievability of the prepared nanoadsorbent was studied and indicated that it could be isolated effectively and reused in three consecutive cycles without remarkable adsorption efficiency loss

Silver-assisted reduction of nitroarenes by an Ag-embedded curcumin/melamine-functionalized magnetic nanocatalyst

Abstract In the current study, we introduce a hybrid magnetic nanocomposite comprised of curcumin (Cur), iron oxide magnetic nanoparticles (Fe3O4 MNPs), melamine linker (Mel), and silver nanoparticles (Ag NPs). Initially, a facile in situ route is administrated for preparing the Fe3O4@Cur/Mel-Ag effectual magnetic catalytic system. In addition, the advanced catalytic performance of the nanocomposite to reduce the nitrobenzene (NB) derivatives as hazardous chemical substances were assessed. Nevertheless, a high reaction yield of 98% has been achieved in short reaction times 10 min. Moreover, the Fe3O4@Cur/Mel-Ag magnetic nanocomposite was conveniently collected by an external magnet and recycled 5 times without a noticeable diminish in catalytic performance. Therefore, the prepared magnetic nanocomposite is a privileged substance for NB derivatives reduction since it achieved notable catalytic activity

Fabrication of a magnetic nanocomposite based on natural hydrogel: Pectin, tragacanth gum, silk fibroin, and integrated graphitic carbon nitride for hyperthermia and biological features

The current study aimed to design and synthesize a new magnetic nanobiocomposite and assess its potential for biological applications and hyperthermia. For this purpose, in the first step, the Pectin (PC) and Tragacanth gum (TG) polymer was synthesized using CaCl2 as a cross-linking agent (PC-TG hydrogel). In the second step, natural Silk fibroin (SF) protein and graphitic carbon nitride (CN) were added to the hydrogel to upgrade the nanobiocomposite's strength and due to CN's pharmacology applications, respectively. Finally, for an enhanced hyperthermia application, PC-TG hydrogel/SF/CN was in situ magnetized with Fe3O4 magnetic nanoparticles (MNPs), and PC-TG hydrogel/SF/CN/Fe3O4 nanobiocomposite was synthesized. By using a vibrating-sample magnetometer (VSM), Fourier-transformed infrared (FTIR), thermogravimetric analysis (TGA), energy dispersive X-ray (EDX), X-ray diffraction (XRD), and field-emission scanning electron microscope (FESEM), the structural features and properties of the PC-TG hydrogel/SF/CN/Fe3O4 nanobiocomposite were determined. This magnetic nanobiocomposite's saturation magnetization value was 14.84 emu g-1. The hemolytic assay of this new nanobiocomposite demonstrated that the hemolysis percentage was 1.07 %, around 99.0 % of cells were able to survive, and the MTT assay was used to assess the anticancer activity against breast cancer cell lines (BT549). Additionally, 62.51 (W g-1) in 200.0 kHz was found to be the greatest specific absorption rate (SAR). These findings suggest that the recently created magnetic nanobiocomposite might function admirably in hyperthermia treatment when exposed to an alternating magnetic field

Cerium functionalized graphene nano-structures and their applications; A review

Graphene-based nanomaterials with remarkable properties, such as good biocompatibility, strong mechanical strength, and outstanding electrical conductivity, have dramatically shown excellent potential in various applications. Increasing surface area and porosity percentage, improvement of adsorption capacities, reduction of adsorption energy barrier, and also prevention of agglomeration of graphene layers are the main advantages of functionalized graphene nanocomposites. On the other hand, Cerium nanostructures with remarkable properties have received a great deal of attention in a wide range of fields; however, in some cases low conductivity limits their application in different applications. Therefore, the combination of cerium structures and graphene networks has been widely invesitaged to improve properties of the composite. In order to have a comprehensive information of these nanonetworks, this research reviews the recent developments in cerium functionalized graphene derivatives (graphene oxide (GO), reduced graphene oxide (RGO), and graphene quantum dot (GQD) and their industrial applications. The applications of functionalized graphene derivatives have also been successfully summarized. This systematic review study of graphene networks decorated with different structure of Cerium have potential to pave the way for scientific research not only in field of material science but also in fluorescent sensing, electrochemical sensing, supercapacitors, and catalyst as a new candidate. 2022 Elsevier Inc.The authors of this paper would like to express their gratitude to the Iran National Science Foundation ( INSF 98016067 ) for the financial support. We also gratefully acknowledge the support from the University of Tehran .Scopu