Effect of sulfur doping of zinc-imidazole coordination polymer (ZnIm CP) as a novel photocatalyst for degradation of ionic dyes.

Zinc-Imidazole coordination polymer (ZnImCP) was simply synthesized hydrothermally at relatively low temperature (70 °C) from zinc acetate and imidazole. ZnImCP was treated by sulfide solution to produce sulfur-doped samples (S-ZnImCPs). Structures of the synthesized ZnImCP and S-ZnImCPs were characterized through FTIR, PXRD, and, Raman, SEM/EDX, N2-BET, UV-VIS DRS, and pHpzc analyses. The photocatalytic performances of pristine CP and sulfur modified CPs under visible and ultra-violet irradiations for degrading the cationic methylene blue (MB) and the anionic methyl orange (MO) were investigated considering different initial pH values 4, 7 and 10. Under visible light, the results indicate that these CPs display considerable photocatalytic degradation towards the cationic MB for the initial pH 4 and 7 where degradation increases with sulfur content. While under ultra-violet, results indicate considerable photocatalytic degradation towards both dyes for the initial pH 7 and 10 where degradation increases with sulfur content which indicates the gainful of non-metal dopping. The buffering nature of CPs and the type of radiation considering determined band-gap values effectively influence the degradation mechanisms.

Designing bimetallic zeolitic imidazolate frameworks (ZIFs) for aqueous catalysis: Co/Zn-ZIF-8 as a cyclic-durable catalyst for hydrogen peroxide oxidative decomposition of organic dyes in water.

ZIF-8 is well known hybrid material that is self-assembled from inorganic and organic moieties. It has several potential applications due to its unique structure. One of these potential applications is in advanced oxidation processes (AOP) via a heterogeneous catalysis system. The use of modified ZIF-8/H2O2 for the destruction of the azo dye methyl orange (MO) is presented in this work to explore its efficacy. This work presents the bimetallic Co/Zn-ZIF-8 as an efficient catalyst to promote H2O2 oxidation of the MO dye. Co/Zn-ZIF-8 was synthesized through a hydrothermal process, and the pristine structure was confirmed using XRD, FTIR, and XPS. The Co/Zn-ZIF-8/H2O2 system successfully decolorized MO at the selected pH 6.5. It was found that more than 90% of MO (10 ppm) was degraded within only about 50 minutes. Proposed radical and redox mechanisms are presented for H2O2 decomposition where the redox mechanism is suggested to predominate via a Co(ii)/Co(iii) redox consecutive cyclic process.

Advances of the highly efficient and stable visible light active photocatalyst Zr(IV)-phthalate coordination polymer for the degradation of organic contaminants in water.

This work presents the restoration of the Zr-phthalate coordination polymer (Zr-Ph CP) via valuable application in photocatalysis. Zr-Ph CP was facilely synthesized using a soft hydrothermal method at 70 °C, and was characterized utilizing FTIR, Raman Spectrosopy, XPS, PXRD, SEM/EDX, BET, and a hyperspectral camera. Assessment of its photocatalytic degradation potential was performed against two different dyes, the cationic methylene blue (MB) and the anionic methyl orange (MO), as frequent models of organic contaminants, under properly selected mild visible illumination (9 W) where the bandgap energy (Eg) was determined to be 2.72 eV. Effects of different initial pH values and different dyes' initial concentrations were covered. Photocatalytic degradation studies showed that Zr-Ph CP effectively degraded both dyes for initial pH 7 within about 40-60 minutes. Degradation rate constants were calculated as 0.17 and 0.13 min-1 for MB and MO, respectively. Generally, both direct and indirect mechanisms share in the degradation, where adsorption has shown an important role. The repeated use of Zr-Ph CP does not significantly affect its photocatalytic performance suggesting high water stability.

Synthesis of a novel Ce(iii)/melamine coordination polymer and its application for corrosion protection of AA2024 in NaCl solution.

We present the synthesis of a new cerium(iii)-melamine coordination polymer (CMCP) by a mixed-solvothermal method and its characterization. Characterization techniques included Raman, Fourier Transformation Infra-Red (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM), in which the change in the electronic environment and the crystallinity were tracked. The characterization results confirm the coordination of cerium(iii) with melamine through -NH2 groups, instead of the N atoms of the triazine ring, for which we propose a mechanism of interaction. In addition, Biovia Materials Studio package was applied to determine and investigate the molecular structure of the CMCP. All simulations were done using COMPASS force-field theory and atom-based method for summation of electrostatic and van de Waals forces. The application of the CMCP for the corrosion inhibition of AA2024 in 3.5% NaCl solution was tested using the potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The results point out that the presence of cerium as cerium(iii) in the CMCP structure plays the fundamental role of inhibition, whereby the inhibition mechanism occurs by cathodic oxidation of Ce(iii) to Ce(iv) and cyclic reduction of Ce(iv) to Ce(iii) by melamine part of CMCP.

3D spectral fluorescence signature of cerium(III)-melamine coordination polymer: A novel sensing material for explosive detection.

Hidden or buried explosives are the most common scenario by terrorist attacks; therefore explosive vapour detection is a vital demand. Explosives are electron deficient materials; the vicinity of explosives to fluorescent material can encounter electron migration. This study reports on facile synthesis of cerium (III)-melamine coordination polymer (CeM-CP) with exclusive optical properties. CeM-CP demonstrated novel spectral fluorescence properties over visible and infrared bands when stimulated with UVA LED source at 385 nm of 100 mW power. Stimulated CeM-CP demonstrated unique spectral fluorescence signal at 400, 700, and 785 nm. These fluorescent signals were correlated to cerium coordination with four nitrogen atoms; vacant orbital will be available for electron excitation migration. Spectral fluorescent signals were quenched as CeM-CP was subjected to TNT vapours. Hyperspectral imaging offered 3D plot of fluorescence signature. The main outcome is that complete fluorescence signal attenuation was achieved at 785 nm. CeM-CP could act as as a novel sensing element for explosive vapour detection.

Gum Arabic polymer-stabilized and Gamma rays-assisted synthesis of bimetallic silver-gold nanoparticles: Powerful antimicrobial and antibiofilm activities against pathogenic microbes isolated from diabetic foot patients.

In this research, irradiation by gamma rays was employed as an eco-friendly route for the construction of bimetallic silver-gold nanoparticles (Ag-Au NPs), while Gum Arabic polymer was used as a capping agent. Ag-Au NPs were characterized through UV-Vis., XRD, EDX, HR-TEM, FTIR, SEM/mapping and EDX analysis. Antibiofilm and antimicrobial activities were examined against some bacteria and Candida sp. isolates from diabetic foot patients. Our results revealed that the synthesis of Ag-Au NPs depended on the concentrations of tetra-chloroauric acid and silver nitrate. HR-TEM analysis confirmed the spherical nature and an average diameter of 18.58 nm. FTIR results assured many functional groups in Gum Arabic which assisted in increasing the susceptibility of incorporation with Ag-Au NPs. Our results showed that, Ag-Au NPs exhibited the highest antimicrobial performance against B. subtilis (14.30 mm ZOI) followed by E. coli (12.50 mm ZOI) and C. tropicalis (11.90 mm ZOI). In addition, Ag-Au NPs were able to inhibit the biofilm formation by 99.64%, 94.15%, and 90.79% against B. subtilis, E. coli, and C. tropicalis, respectively. Consequently, based on the promising properties, they showed superior antimicrobial potential at low concentration and continued-phase durability, they can be extensively-used in many pharmaceutical and biomedical applications.

Initial absolute monocyte count as an immune biomarker for clinical response in acute myeloid leukemia with monocytic differentiation.

BACKGROUND: Absolute monocyte count (AMC) correlates with survival outcomes in various hematologic malignancies. However, its role in myeloid malignancies including AML needs to be highlighted. So, this prospective cohort study aimed to assess the effect of AMC on the treatment outcome and survival in a 56 adult de novo AML patients with monocytic differentiation, admitted to the Clinical Hematology Unit, Internal Medicine Department, in a tertiary referral hospital in Egypt, from July 2016 to June 2019. RESULTS: The initial AMC was measured either by manual differential or the hematology automatic analyzer Sysmex XN-2000 and patients were classified by using receiver operating characteristic curve into two groups monocytopenic (≤ 4 × 109/L) and non-monocytopenic (> 4 × 109/L) group; including 24 (42.9%) and 32 (57.1%) patients, respectively. After a median follow up period of 7.7 (range 0.5-33.2) months, the monocytopenic group was associated with a significantly higher CR rate (P = 0.019), with a lower death as well as relapse and early relapse rates (P = 0.011, 0.033, and 0.002, respectively). Moreover, low initial AMC along with intensive induction were independently associated with complete response to induction chemotherapy with HR, 5.04 [1.37-18.58], P = 0.015, and 5.67 [1.48-21.71], P = 0.011, respectively by using the multivariate logistic regression model. Regarding survival, the monocytopenic group was associated with a better 3-year disease-free survival rate (P = 0.011) in univariate Cox regression only but did not reach significance in the multivariate model and did not affect the overall survival as well. CONCLUSION: Initial AMC was found to be an independent prognostic immune biomarker for treatment response in AML patients with monocytic differentiation. However, it did not appear as an independent predictor of survival in a multivariate analysis.

Corrosion protection mechanism of Ce4+/organic inhibitor for AA2024 in 3.5% NaCl.

Cerium is a rare earth element that has been widely proposed for the corrosion protection of aluminium alloys (AA). Both cerium salts, Ce3+ and Ce4+, have been used in combination with other compounds to offer synergistic inhibition, however, the inhibitive corrosion mechanism when using Ce4+ with organic compounds is still not clear. In this study, the synergistic inhibition effect of Ce4+ and melamine (M) on the corrosion of aluminium alloy 2024 (AA2024) in 3.5% NaCl solution was investigated. Potentiodynamic Polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) techniques were used to study the synergistic effect of different Ce4+/M ratios on the corrosion behaviour of AA2024. The PDP study showed that a combination of 50% Ce4+ and 50% M leads to the lowest corrosion rates, both acting as cathodic inhibitors. Both PDP and EIS results indicated that M or Ce4+ in isolation did not offer effective corrosion protection, while the combination of M and Ce4+ significantly enhances the corrosion protection with a synergism parameter equal to 3.5. SEM and EDX observations confirm the findings from the electrochemical techniques. XPS was used to investigate the mechanism of protection, revealing that the reduction of Ce4+ to Ce3+ occurs during protection of AA2024. A new mechanism of corrosion synergistic inhibition by Ce4+ and organic compounds is postulated where the role of the organic compounds is to enhance the reduction of Ce4+.

Factorial design-optimized and gamma irradiation-assisted fabrication of selenium nanoparticles by chitosan and Pleurotus ostreatus fermented fenugreek for a vigorous in vitro effect against carcinoma cells.

The novelty of the present work looks in the synthesis of aqueous dispersed selenium nanoparticles (Se NPs) using gamma rays with the aid of various natural macromolecules such as citrus pectin (CP), sodium alginate (Alg), chitosan (CS) and aqueous extract of fermented fenugreek powder (AEFFP) using Pleurotus ostreatus for investigating their impact in vitro toward carcinoma cell. The synthesized Se NPs were characterized by XRD, UV-Vis., DLS, HRTEM, SEM, EDX and FTIR. Nucleation and growth mechanisms were also discussed. The factorial design was applied to examine the importance of multiple parameters on Se NPs production with a special focus on temperature and gamma rays influences. FTIR spectrum exhibited the existence of several functional groups in Se NPs-capping macromolecules. Results revealed that Se NPs' size was dramatically-influenced by the type of stabilizer, precursors concentration, pH and the absorbed gamma rays dose. The current research reported the promising antitumor application of Se NPs against Ehrlich Ascites Carcinoma (EAC) and human Colon Adenocarcinoma (CACO) in vitro. The proliferation of EAC was significantly-hindered by Se NPs-CS (38.0 µg/ml) at 60 kGy (IC50 = 23.12%) and Se NPs-AEFFP (19.00 µg/ml) at 15 kGy (IC50 = 7.21%). Also, Se NPs control the generation of CACO cells, IC50 was recorded as 25.32% for Se NPs-CS (38.0 µg/ml) and 8.57% for Se NPs-AEFFP (19.00 µg/ml).

Therapeutic and diagnostic potential of nanomaterials for enhanced biomedical applications.

Biomedical applications of nanomaterials have received considerable attention and interest from many researchers over the past decade due to the key role they can play in enhancing public health. Different types of nanomaterials possess both diagnostic and therapeutic potential owing to their outstanding properties compared to their bulk counterparts. Herein, we present, analyze and provide significant insights and recent advances about the promising biomedical applications of nanoparticles including bioimaging of biological environments and its role as a significant tool for early detection of many diseases with respect to traditional means, explaining their types and limitations. In addition, different types of nanoparticles acting as effective bio-sensors and detectors of our body have been analyzed. Moreover, the therapeutic potential of different types of nanoparticles and their attractive antimicrobial effects allowing them to act as powerful and new drug substitutes against multi-drug resistant bacteria and pathogenic fungi. Finally, we introduce some nanoparticles as powerful antioxidants and promising candidates in cancer therapeutics. We conclude that this review can give up-to-date information about various biomedical applications of nanoparticles and will be of great value and interest to researchers and scientists of materials science, biology, chemistry, and medicine.

Presepsin as a diagnostic marker of bacterial infections in febrile neutropenic pediatric patients with hematological malignancies.

Febrile neutropenia (FN) is often observed in hematological malignancies (HEM). Presepsin is also known as soluble CD14 subtype; it is a glycoprotein fragment derived from monocytes and macrophages. We aimed to evaluate the significance of presepsin and other biomarkers for diagnosis of bacteremia in children with HEM. Sixty pediatric patients with different HEM (acute lymphoblastic leukemia 36, acute myeloid leukemia 12, non-Hodgkin lymphoma 10, and Hodgkin disease 2). Thirty age and sex-matched healthy children serving as control were enrolled in this study. Estimation of presepsin, procalcitonin (PCT), and C-reactive protein (CRP) during episode of FN in addition to absolute neutrophils count (ANC) and blood culture was performed for all the participants. Presepsin levels were higher in the patients than in control with a higher increments in the positive blood cultures than the sterile cases. Presepsin concentration was significantly higher in bacteremia than clinically proved infection and fever of unknown origin. A statistically significant positive correlation between presepsin and CRP plus PCT levels but negative correlation with ANC were observed in the patients subgroups. Presepsin is a useful marker for detection of bacteremia with sensitivity and specificity (100 and 85.7%). This finding supported that presepsin was superior to PCT and CRP in identifying bacterial infection in FN.

Detection of minimal residual disease in childhood B-acute lymphoblastic leukemia by 4-color flowcytometry.

Monitoring of minimal residual disease (MRD) is currently considered the most powerful predictor of outcome in acute lymphoblastic leukemia (ALL). Achievement of a negative MRD state assessed by multicolor flowcytometry (MFC) is an important predictor of disease-free survival (DFS) and overall survival (OS) in ALL patients. We sought to determine whether panels of antibodies combination are more suitable for detection of MRD in Childhood ALL. Eighty-four (84) patients with ALL (B-lineage subtype) were enrolled in this study. Normal template for B cell precursors was established in 15 control participants using 4-four panels of monoclonal Antibodies (Mo Abs),{CD22, CD45, CD58 and CD97 in combination with CD10, CD19, CD34}. At diagnosis, CD22 exhibited the lowest incidence of expression in only 50% of all patients, while CD45, CD58, and CD97 were expressed in 80.9, 59.5 and 92.8%, respectively. Analysis of MRD was performed for each Mo Abs combination at day 0 and day 14 post-induction of chemotherapy by 4-color (FCM). The incidence of MRD was 61.9, 70.6, 60.0 and 55.1% for CD22, CD45, CD58 and CD97, respectively. In B-ALL patients, (CD10/CD19/CD34/CD45) + (CD10/CD19/CD34/CD97) represented the highest incidence of expression of leukemic cells markers with a significant correlation with blasts count, suggesting that these are more specific for MRD detection. Also FCM is relatively cost effective for detection of MRD in ALL patients and its applicability in routine leukemia lab is valuable. MRD evaluation at the end of the induction therapy (i.e. day 35 or 42 according to the different schedules) is advised. Also, Ig/T cell receptor gene rearrangements and gene fusions analyzed by polymerase chain reaction (PCR) are preferred.

Clinical significance of T-regulatory cells in B-cell non-Hodgkin's lymphoma.

Regulatory T cells (Tregs) play a central role in protecting the host from autoimmune diseases. However, Tregs also pose a major problem to anti-tumor immunity. The expansion and accumulation of these immunosuppressive cells correlate with advanced tumor growth and predict poor disease prognosis. The study aims at evaluation of the clinical role of regulatory T cells in B-cell Non-Hodgkin's lymphoma. The study was carried out on 45 de novo patients with B- NHL, they included 26 males and 19 females and 20 apparently healthy age-matched as control. Diagnosis of lymphoma was done by lymph node biopsy, 15 patients had diffuse large B cell lymphoma (DLBCL), 9 follicular lymphoma (FL), 8 small cell lymphocytic lymphoma (SCLL), 7 marginal zone lymphoma (MZL) and 6 had mantle cell lymphoma (MCL). Tregs (CD4+CD25+ FoxP+3) were analyzed by Flowcytometry. The mean percent was 10.9 +/- 1.6% in diffuse large B cell lymphoma, 12.4 +/- 1.4% in follicular lymphoma, 13.7 +/- 2.4% in small cell lymphocytic lymphoma, 11.9 +/- 1.9% in marginal zone lymphoma and 13.5 +/- 1.35% in mantle cell lymphoma as compared to 5.9 +/- 0.96% in controls with a significant increase in the patients in relation to control group. Tregs was significantly increased in advanced stages of the disease, in bone marrow infiltration and in patients with increased LDH level. In conclusion, Tregs may play a role in modifying immune responses in patients with lymphomas and may be useful in immunotherapy and new anti-lymphoma strategies involving depletion of Tregs.

Melamine-formaldehyde-NTA chelating gel resin: Synthesis, characterization and application for copper(II) ion removal from synthetic wastewater.

A new chelating resin was synthesised by anchoring nitrilotriacetic acid (NTA) to melamine during the melamine-formaldehyde gelling reaction in the presence of water, using acetone and guaiacol as a porogen mixture. This technique gives a porous chelating gel resin capable of removing heavy metals from wastewater. FT-IR, XRD, elemental analysis, surface area and water regain measurements were conducted for characterization of the new chelating gel resin. A comprehensive adsorption study (kinetics isotherm, and thermodynamics) of Cu(II) removal from synthetic acidic aqueous solutions by adsorption on this resin was conducted regarding the effects of time, temperature, initial pH and copper(II) initial concentration.