31 research outputs found

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

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    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

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

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    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

    Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

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    Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

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

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    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 of a new trend conjugate vaccine for the prevention of Klebsiella pneumoniae

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    <em>Klebsiella pneumoniae</em> is a major cause of nosocomial pneumonia, septicemia and urinary tract infections, especially in newborns, blood cancer patients, and other immunocompromised candidates. The control of <em>K. pneumoniae</em> is a complicated issue due to its tight pathogenesis. Immuno-prophylactic preparations, especially those directed toward the <em>bacterium</em> O-antigen, showed to be the most successful way to prevent the infection incidence. However, all previously proposed preparations were either of limited spectrum or non-maternal, and hence not targeting the main <em>Klebsiella</em> patients. Moreover, all preparations were directed only to prevent the respiratory diseases due to that pathogen. This article addresses the development of a method originally used to purify the non-capsular bacterial- endotoxins, as a new and easy method for vaccine production against <em>K. pneumoniae</em>. The application of this method was preceded by a biotechnological control of capsular polysaccharide production in <em>K. pneumoniae</em>. The new produced natural conjugate between the bacterial O-antigen and its outer membrane proteins was evaluated by physicochemical and immunological methods to investigate its purity, integrity, safety and immunogenicity. It showed to be pure, stable, safe for use, and able to elicit a protective immunoglobulin titer against different <em>Klebsiella</em> infections. This immune-response proved to be transferable to the offspring of the vaccinated experimental rabbits via placenta

    Real time RT-PCR assay for detection of different serotypes of FMDV in Egypt

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    Aim: The present study indicated that rRT-PCR could be provided for the detection of FMDV in infected, contact and carrier cattle and also provide a rapid sensitive tool aiming to aid in rapid disease detection and control. Foot and Mouth disease virus serotypes O and A still existing in Egypt. In January 2012, sever outbreaks struck the animal population in most Egyptian 1 governorates. The causative virus was identified as FMDV SAT2. Material and Methods: Five samples of tongue epithelium (ET) and five oesophageal-pharyngeal (OP) fluid samples were collected from FMD suspected cattle in infected farm at El-Fayoum and 20 OP samples from in-contact cattle at the same farm in addition to 30 OP samples from apparently healthy cattle at three different localities in El-Fayoum governorate (12 from Fayoum; 9 from Sinoras and 9 from Edsa) in order to detect carrier cattle. All of these samples were collected during November and December 2011 and January 2012. Results: All the ET and OP samples were inoculated on BHK cell culture and baby mice. The obtained results were identified using complement fixation test in addition to real-time reverse transcriptase polymerase chain reaction (rRT-PCR). In the infected farm at El-Fayoum FMDV type SAT2 was detected in cattle which are considered as the first introduction of this type while FMDV type O and SAT2 were detected in the in-contact cattle in the same farm. The sensitivity of rRT-PCR was cleared in the in-contact cattle as 13 out of 20 OP samples were positive to FMDV by rRT-PCR while 11 out of 20 OP samples were positive to FMDV by CFT. The OP samples collected from apparently healthy cattle from Fayoum, Sinoras and Edsa localities in Fayoum governorate demonstrate the circulation of the FMDV type A, O and the recent SAT2 in carrier cattle which threaten cattle population in Fayoum governorate. Also the sensitivity of real time RT-PCR over the CFT in detection of FMDV carrier cattle was clearly noticed in these localities as 19 out of 30 OP samples were positive by rRT-PCR while in contrast there were only 16 out of 30 samples positive by CFT. Conclusion: In conclusion, this study demonstrates that real-time RT-PCR currently used at the WRL for FMD provides an extremely sensitive and rapid additional procedure for improved laboratory diagnosis of FMD especially in-contact and carrier cases. The rRT-PCR generated results in less than one day from test commencement, in contrast to up to four days to define some positive and all negative samples by combined use of CFT and virus isolation. This is an important feature when definitive diagnostic results are required in a short timescale during emergencies. Also this study demonstrates the current situation of FMDV circulating in EL-Fayoum governorate and the introduction of new SAT2 serotype beside type A and O. [Vet World 2012; 5(12.000): 732-737

    Study of electron spin resonance and viscosity for hemoglobin polymer after arsenic trioxide and gamma irradiation treatment

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    AbstractThe present work aimed to study the intensity of electron spin resonance (ESR) of hemoglobin rat's polymer and changes in rheological properties (viscosity). This study included five groups: control, irradiation with single dose of 5 Gy gamma irradiation, intraperitoneal injection with single dose of arsenic trioxide (As2O3) 10 mg/kg body weight, As2O3 followed by 5 Gy and 5 Gy followed by As2O3. The results of ESR spectroscopy indicated that the intensity increases significantly for As2O3 and non-significantly with 5 Gy of gamma radiation compared with control, which indicated an increase in the number of free radicals. Injection with As2O3 after and before 5 Gy resulted in non-significant decrease which given rise to a decrease in the number of free radicals. there was significant decrease in viscosity for 5 Gy at different shear rates (11.3–375 sec−1), viscosity for As2O3 injection group showed non-significant decrease, and non-significant increase in case of 5 Gy followed by As2O3 injection, significant decrease at high shear rate in case of 5 Gy followed by As2O3. These results concluded that 5 Gy followed by As2O3 showed some sort of repair in the function of rats hemoglobin rather than injection with As2O3 and 5 Gy both individually

    Adsorption of Polyvinylpyrrolidone over the Silica Surface: As Affected by Pretreatment of Adsorbent and Molar Mass of Polymer Adsorbate

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    The adsorption of polyvinylpyrrolidone over the surface of silica has been investigated. The impact of molar mass of the polymer, pH, and pretreatment temperature of silica particles have been evaluated by means of FTIR spectroscopy and electrophoretic measurements. The silica particles used have narrow particle size distribution. The zeta potential of the aqueous silica suspension was decreased with the increase in pH. The amount of polymer adsorbed was increased with the increase in pretreatment temperature, time, concentration, pH, zeta potential, and molar mass of the polymer. The addition of polymer to the system increased the zeta potential due to adsorption of polymer on the surface of the particles. However, the impact increased with the increase in molecular mass of the polymer. The IR spectra obtained before and after adsorption of polymer concluded that, mostly, hydrogen bonding is responsible for the adsorption phenomena; however, hydrophobic interactions also play a significant role. The mechanism has been investigated and established through FTIR spectroscopy

    Non-Linear Optical Property and Biological Assays of Therapeutic Potentials Under In Vitro Conditions of Pd(II), Ag(I) and Cu(II) Complexes of 5-Diethyl amino-2-({2-[(2-hydroxy-Benzylidene)-amino]-phenylimino}-methyl)-phenol

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    Herein, we report facile procedures for synthesis of a new Schiff base ligand (H2L,5-Diethylamino-2-({2-[(2-hydroxy-benzylidene)-amino]-phenylimino}-methyl)-phenol) and its Ag(I), Pd(II) and Cu(II) complexes. The structure of the H2L ligand as well as its metal complexes was deduced based on wide range of analytical, structural and spectroscopic tools, along with theoretical evidence via density functional theory (DFT) calculations. The obtained results indicated that the Schiff base (H2L) ligand acts as a tetradentate N2O2 donor with two azomethine nitrogen&rsquo;s (N1, N2) and two deprotonated phenolic oxygens (O1, O2) atoms. A distorted octahedral structure is assigned to [CuL(OH2)2]&middot;3/2H2O complex and square planar structure for PdL and AgL complexes. The electronic structure and non-linear optical (NLO) property of the prepared compounds were discussed theoretically by the B3LYP/GENECP program. Results revealed that all complexes have non-planner geometries as indicated from the dihedral angles. The charge transfer occurs within the synthesized complexes as indicated from the calculated energy gap between HOMO and LUMO energies. The H2L ligand and its complexes are excellent candidates for NLO materials as implied from their hyperpolarizabilities and polarizabilities values. The biological activities of the prepared complexes against selected microorganisms and cancer cell lines gave good growth inhibitory effect. The biocidal potencies of the ligand and its complexes can be arranged as follows: AgL &gt; CuL &gt; PdL &gt; H2L, as compared to the used standard drugs. The antiproliferative activity of the studied complexes against different carcinoma cell lines such as liver (Hep-G2), breast (MCF-7) and colon (HCT-116) followed the order H2L &lt; AgL&lt; PdL &lt; CuL &lt; vinblastine. Probing the binding interactions of prepared complexes with calf thymus (CT)-DNA using electronic absorption, gel electrophoresis and viscosity measurements revealed strong interaction via intercalation modes, as also evidenced by their molecular docking study

    Synthesis, characterization, molecular structure and supramolecular architectures of some copper(II) complexes derived from salicylaldehyde semicarbazone

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    A series of new copper(II) complexes, [Cu(HSalsc)Cl]center dot 1/2H(2)O (1), [{Cu(HSalsc)}(2)(NO3)(2)][{Cu(HSalsc)}(2)- NO3)center dot H2O]NO3 (2), [{Cu(Salsc)}(2)]H2O (3), [Cu(HSalsc)(HIm)]Cl center dot 1/2H(2)O (4), [{Cu(HSalsc)HIm}(2)](NO3)(2) (5) and [Cu(HSalsc)(HIm)]OAc (6) derived from salicylaldehyde semicarbazone (H(2)Salsc) have been prepared and characterized by elemental analysis, infrared and UV-Vis absorption spectra as well as electrospray mass spectra (ESI-MS). The crystal and molecular structure of 1, 2, 5 and 6 have been determined by X-ray single crystal diffraction. The supramolecular architectures in 1, 2, 5 and 6 have been also discussed. (C) 2015 Elsevier B.V. All rights reserved
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