Nano Sized Moringa oleifera an Effective Strategy for Pb(II) ions Removal from Aqueous Solution

Nano-sized  Moringa oleifera is considered an effective   biosorbent  with  high surface area from agricultural waste, low coast and environment-friendly which can be used for removal of  Pb2+ from waste water. Thus our study stem to investigate the ability of natural nano-sized biosorbents for removing  very toxic Pb2+ ions from aqueous solution. The investigated biosorbent (Moringa oleifera) was characterized by FTIR, SEM, TEM, XRD and EDX techniques. Moreover, the influence of pH, temperature, adsorbent dosage, contact time and initial metal ion concentration on adsorption process were investigated. The maximum biosorption capacities (qm) of Pb2+ ions by Moringa oleifera was 37.9 mg/g. The lowest biosorption was observed (61.4%) for Pb2+ ions at pH 2.0 while the highest one (94.36%) at pH 5. The optimum contact time for the adsorption process was found to be at 60 minutes. The amount of Pb2+ ions adsorbed increases with increasing in initial metal ion concentration. Moreover, biosorption capacity (qe) and removal efficiency of Pb2+ ions solutions increase as temperature increases. FT-IR data indicated that the adsorption of metal ions occurs on the surface of Moringa oleifera powder as the main functional groups that are responsible for metal ions binding are involved in the process. Furthermore, Thermodynamic studies confirmed that the biosorption process was endothermic and the positive value of ΔG° is quite common when an ion-exchan­­ge mechanism applies in the biosorption. The Positive value of ΔS◦ suggested an increase in randomness during the biosorption. The kinetics study of sorption indicates that the pseudo second-order model provides better correlation of the sorption data (R2=0.99) than the pseudo first-order model (R2 = 0.91), confirming the chemisorption of metal ions solutions on Moringa oleifera. The Freundlich isotherm has agood fit with the experimental data (R2 close to 1) compared to Langmuir isotherm (R2=0.99). This study shows that Moringa oleifera are available, low cost, effective and environment friendlly biosorbent for the removal of Pb2+ ions from aqueous environment. Keywords: Lead, biosorption, Thermodynamics, kinetics, removal efficiency, Moringa oleifera, isother

Kinetic investigation of hydroxide ion and DNA attack on some high spin iron (II) chelates Bearing ONO Donors amino acid Schiff bases

The reactivity of few novel high spin Fe(II) complexes of Schiff base ligands derived from 2-hydroxynaphthaldehyde and some variety of amino acids with OH- ion has been examined in aqueous mixture at temperature in the range 10–40 Co. Based on the kinetic investigations, the rate law and a plausible mechanism were proposed and discussed. The general rate equation was suggested as follows: rate = kobs [Complex], where kobs.= k1 + k2 [OH-]. Base catalyzed hydrolysis kinetics measurements imply pseudo-first order doubly stage rates due the presence of merand fac-isomers. The observed rate constants kobs are correlated the effect of substituent R in the structure of the ligands. From the effect of temperature on the rate; various thermodynamic parameters have been evaluated. The evaluated rate constants and activation parameters are in a good agreement with the stability constants of the investigated complexes

Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic

Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 109 institutions in 41 countries. Inclusion criteria: children <18 years who were newly diagnosed with or undergoing active treatment for acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, retinoblastoma, Wilms tumour, glioma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, medulloblastoma and neuroblastoma. Of 2327 cases, 2118 patients were included in the study. The primary outcome measure was all-cause mortality at 30 days, 90 days and 12 months. Results All-cause mortality was 3.4% (n=71/2084) at 30-day follow-up, 5.7% (n=113/1969) at 90-day follow-up and 13.0% (n=206/1581) at 12-month follow-up. The median time from diagnosis to multidisciplinary team (MDT) plan was longest in low-income countries (7 days, IQR 3-11). Multivariable analysis revealed several factors associated with 12-month mortality, including low-income (OR 6.99 (95% CI 2.49 to 19.68); p<0.001), lower middle income (OR 3.32 (95% CI 1.96 to 5.61); p<0.001) and upper middle income (OR 3.49 (95% CI 2.02 to 6.03); p<0.001) country status and chemotherapy (OR 0.55 (95% CI 0.36 to 0.86); p=0.008) and immunotherapy (OR 0.27 (95% CI 0.08 to 0.91); p=0.035) within 30 days from MDT plan. Multivariable analysis revealed laboratory-confirmed SARS-CoV-2 infection (OR 5.33 (95% CI 1.19 to 23.84); p=0.029) was associated with 30-day mortality. Conclusions Children with cancer are more likely to die within 30 days if infected with SARS-CoV-2. However, timely treatment reduced odds of death. This report provides crucial information to balance the benefits of providing anticancer therapy against the risks of SARS-CoV-2 infection in children with cancer

Machine Learning Identifies Stemness Features Associated with Oncogenic Dedifferentiation.

Cancer progression involves the gradual loss of a differentiated phenotype and acquisition of progenitor and stem-cell-like features. Here, we provide novel stemness indices for assessing the degree of oncogenic dedifferentiation. We used an innovative one-class logistic regression (OCLR) machine-learning algorithm to extract transcriptomic and epigenetic feature sets derived from non-transformed pluripotent stem cells and their differentiated progeny. Using OCLR, we were able to identify previously undiscovered biological mechanisms associated with the dedifferentiated oncogenic state. Analyses of the tumor microenvironment revealed unanticipated correlation of cancer stemness with immune checkpoint expression and infiltrating immune cells. We found that the dedifferentiated oncogenic phenotype was generally most prominent in metastatic tumors. Application of our stemness indices to single-cell data revealed patterns of intra-tumor molecular heterogeneity. Finally, the indices allowed for the identification of novel targets and possible targeted therapies aimed at tumor differentiation

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Development, structural investigation, DNA binding, antimicrobial screening and anticancer activities of two novel quari-dentate VO(II) and Mn (II) mononuclear complexes

Two novel VO(II) and Mn(II) imine chelates derived from the condensation of o-phenylenediamine (PN) with 3-ethoxysalicylaldehyde(ES) were synthesized. The prepared ESPN imine ligand and its chelates were investigated via different analytical and physicochemical tools. Correlation between all the obtained results, the parent ligand behaves as tetra-dentate ONNO ligand and coordinates to Mn(II) and VO(II), in octahedral and square pyramidal geometry, respectively. Also, the prepared compounds were screened for their antimicrobial activities on different pathogenic bacteria and fungi. The results show that the complexes have a stronger antimicrobial activity in comparison with its ligand. Moreover, the interaction of the prepared metal chelates with CT-DNA was detected utilizing spectral studies, viscosity and gel electrophoreses measurements. The obtained results clearly demonstrate that, the binding affinity with CT-DNA for ESPN > ESPNV complex. Furthermore, the cytotoxic activity of the tested compounds on human colon carcinoma cells, hepatic cellular carcinoma cells and breast carcinoma cells has been examined. From these results it was found that the investigated complexes have effective cytotoxicity against growth of carcinoma cells with respect of its imine ligand. Keywords: Imines, Structural elucidation, Antimicrobial screening, DNA binding, Anticancer efficienc

Kinetic investigation of hydroxide ion and DNA attack on some high spin iron (II) chelates Bearing ONO Donors amino acid Schiff bases

The reactivity of few novel high spin Fe(II) complexes of Schiff base ligands derived from 2-hydroxynaphthaldehyde and some variety of amino acids with OH- ion has been examined in aqueous mixture at temperature in the range 10–40 Co. Based on the kinetic investigations, the rate law and a plausible mechanism were proposed and discussed. The general rate equation was suggested as follows: rate = kobs [Complex], where kobs.= k1 + k2 [OH-]. Base catalyzed hydrolysis kinetics measurements imply pseudo-first-order doubly stage rates due the presence of merandfac-isomers. The observed rate constants kobs are correlated the effect of substituent R in the structure of the ligands.From the effect of temperature on the rate; various thermodynamic parameters have been evaluated. The evaluated rate constants and activation parameters are in a good agreement with the stability constants of the investigated complexes.Keywords: Base catalyzed hydrolysis, Isomer, Reaction mechanism, Thermodynamic parameters