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Synthesis of zinc ferrite nanoparticles and evaluation of their antifungal properties at different temperatures
No full textZinc ferrite nanoparticles have been synthesized by the co-precipitation method where Polyethylene Glycol act as the capping agent. The sample structure and morphology of the product were analysed by powder XRD, FTIR, U-V visible spectroscopy and scanning electron microscope (FE-SEM). The prepared NPs were annealed at varying temperatures such as 500◦C, 600◦C and 700◦C. The XRD data confirms the presence of nanosized ZnFe2O4 particles and the X-ray density of the sample and their particle size increases linearly along with the increase in annealing temperature, but the lattice parameter changes inversely. The FTIR data also provide information about nanosized zinc ferrite particles. The surface characteristics of ZnFe2O4 were observed by FESEM. The anti-fungal properties of zinc ferrite were observed by FESEM. The anti-fungal properties of zinc ferrite nanoparticles were also evaluated
Burden of Typhoid and Paratyphoid Fever in India
No full textIn 2017, more than half the cases of typhoid fever worldwide were projected to have occurred in India. In the absence of contemporary population-based data, it is unclear whether declining trends of hospitalization for typhoid in India reflect increased antibiotic treatment or a true reduction in infection
Widespread support for a global species list with a formal governance system
No full textTaxonomic data are a scientific common. Unlike nomenclature, which has strong governance institutions, there are currently no generally accepted governance institutions for the compilation of taxonomic data into an accepted global list. This gap results in challenges for conservation, ecological research, policymaking, international trade, and other areas of scientific and societal importance. Consensus on a global list and its management requires effective governance and standards, including agreed mechanisms for choosing among competing taxonomies and partial lists. However, governance frameworks are currently lacking, and a call for governance in 2017 generated critical responses. Any governance system to which compliance is voluntary requires a high level of legitimacy and credibility among those by and for whom it is created. Legitimacy and credibility, in turn, require adequate and credible consultation. Here, we report on the results of a global survey of taxonomists, scientists from other disciplines, and users of taxonomy designed to assess views and test ideas for a new system of taxonomic list governance. We found a surprisingly high degree of agreement on the need for a global list of accepted species and their names, and consistent views on what such a list should provide to users and how it should be governed. The survey suggests that consensus on a mechanism to create, manage, and govern a single widely accepted list of all the world’s species is achievable. This finding was unexpected given past controversies about the merits of list governance
Mitochondrial gene expression signature predicts prognosis of pediatric acute myeloid leukemia patients
No full textIntroduction: Gene expression profile of mitochondrial-related genes is not well deciphered in pediatric acute myeloid leukaemia (AML). We aimed to identify mitochondria-related differentially expressed genes (DEGs) in pediatric AML with their prognostic significance.
Methods: Children with de novo AML were included prospectively between July 2016-December 2019. Transcriptomic profiling was done for a subset of samples, stratified by mtDNA copy number. Top mitochondria-related DEGs were identified and validated by real-time PCR. A prognostic gene signature risk score was formulated using DEGs independently predictive of overall survival (OS) in multivariable analysis. Predictive ability of the risk score was estimated along with external validation in The Tumor Genome Atlas (TCGA) AML dataset.
Results: In 143 children with AML, twenty mitochondria-related DEGs were selected for validation, of which 16 were found to be significantly dysregulated. Upregulation of SDHC (p<0.001), CLIC1 (p=0.013) and downregulation of SLC25A29 (p<0.001) were independently predictive of inferior OS, and included for developing prognostic risk score. The risk score model was independently predictive of survival over and above ELN risk categorization (Harrell’s c-index: 0.675). High-risk patients (risk score above median) had significantly inferior OS (p<0.001) and event free survival (p<0.001); they were associated with poor-risk cytogenetics (p=0.021), ELN intermediate/poor risk group (p=0.016), absence of RUNX1-RUNX1T1 (p=0.027), and not attaining remission (p=0.016). On external validation, the risk score also predicted OS (p=0.019) in TCGA dataset.
Discussion: We identified and validated mitochondria-related DEGs with prognostic impact in pediatric AML and also developed a novel 3-gene based externally validated gene signature predictive of survival
Multifunctional alternating “bitter-sweet” macromolecular architecture.
No full textThe design and synthesis of a multifunctional macromolecular architecture featuring alternating cholic acid (CA) and glucose pendants in a polymer side-chain is reported. The target architecture was prepared by reversible addition–fragmentation chain-transfer copolymerization of styrene-conjugated CA (the bitter monomer) and acetyl-protected glucose appended maleimide (the sweet monomer) using the polyethylene glycol-conjugated chain transfer agent. Removal of the acetates resulted in amphiphilic “bitter-sweet” alternating copolymers that were self-assembled in aqueous media having CA containing bitter core and sugar-coated sweet shell. Dynamic light scattering measurements in water, field emission scanning electron microscopy, and transmission electron microscopy confirmed the formation of 40 to 75 nm sized micellar nanoscaffolds, depending on the chain-length of the copolymers. The nanoparticles successfully encapsulated hydrophobic molecules as witnessed via fluorescence spectroscopy using Nile red as an exemplary guest. Interestingly, the alternating copolymer recognized β-cyclodextrin (β-CD) through the formation of inclusion complexes with lateral cholate moieties in the polymer as evident from 2D NMR and nuclear Overhauser effect experiments. It is worth noting that the polymer and its inclusion complex were found to be capable of recognizing Concanavalin A (Con A), as shown by turbidimetric assay and isothermal titration calorimetry. Interestingly, the inclusion complex of the alternating copolymer showed significantly higher autofluorescence in the presence of Con A with respect to that of un-complexed one. Thus, the present study offers a simple way to prepare a multifunctional alternating copolymer having hydrophobic molecule encapsulation, inherent fluorescence, inclusion complex formation with β-CD, and lectin recognition capabilities
Spinal atypical teratoid rhabdoid tumor-narrative review and report of a rare case managed with multimodality approach
No full textBackground
Spinal atypical teratoid rhabdoid tumor (AT/RT) is an extremely rare tumor and represents less than 2% of all AT/RTs.
Methods
Available medical literature on spinal AT/RT in English was retrieved from PubMed and comprehensively reviewed. Clinical presentation, diagnosis, management, prognosis, and outcome in patients with spinal AT/RT have been elucidated by citing a case of extradural AT/RT of the cervicodorsal spine.
Results
The age at presentation is usually less than 3 years. The most common site is the cervicodorsal spine. The most frequent tumor location is intradural extramedullary. A contrast-enhanced magnetic resonance imaging (MRI) of the entire neuraxis is the imaging modality of choice. The incidence of leptomeningeal dissemination is high (15–30%). Histopathological examination shows an admixture of primitive neuroectodermal, mesenchymal, and epithelial elements along with rhabdoid cells. Loss of SMARCB1/INI1 is considered pathognomonic of AT/RT. Maximal safe resection of tumor is the initial management of choice. Thereafter focal radiotherapy for localized tumor or craniospinal irradiation for leptomeningeal dissemination should be considered. Post-operative intensive polychemotherapy including intrathecal and high-dose chemotherapy (with autologous stem cell rescue) is usually considered to optimize survival. Typically, the time to recurrence and overall survival are less than 6 and 12 months, respectively. However, with judicious multimodality management long-term survivors are increasingly being recognized. The illustrative patient was a 18-month-old girl diagnosed with extradural AT/RT of the cervicodorsal spine (C3-D1), who was managed with maximal safe resection of tumor, multiagent chemotherapy (ICE-ifosfamide, carboplatin, etoposide) and focal RT to the tumor bed—50.4 Gy/28 fractions/5.5 weeks. At the last follow-up visit, 30 months after surgery, she had complete clinicoradiological response.
Conclusio
Autologous stem cell transplantation in adult hodgkin lymphoma at a tertiary care center in india: analysis of outcomes and prognostic factors
No full textHigh-dose chemotherapy and autologous stem cell transplant (ASCT) is the standard of care treatment in relapsed/refractory Hodgkin lymphoma (rrHL). Published long-term follow-up data concerning this modality from the Indian subcontinent is lacking. In this retrospective study, the data on adults (< 16 years) with biopsy-confirmed rrHL who were autografted from 1 January 2000 to 31 December 2021 at our transplant unit were analyzed. Progression-free survival (PFS) was defined as time from transplant to disease progression or death due to any cause. Overall survival (OS) was determined from date of transplant to date of death due to any cause. Overall, 134 patients with Hodgkin lymphoma underwent ASCT. At a median follow-up of 38.2 (range, 0.1–240) months, 5 years PFS was 45.3% (95% CI 35.4–54.4). The probability of OS at 5 years was 60.5% (95% CI 49.6–69.6). Eleven (8.2%) patients suffered transplant-related mortality by 100 days. Post-transplant persistent disease, pre-transplant serum hypoalbuminemia (< 3.5 g/dl) and chemo-resistance (< PR after last salvage regimen) of tumour at transplant were independent prognostic factors associated with worse PFS in multivariable analysis. Likewise, age ≥ 30 years, ECOG performance status ≥ 1 and residual disease after transplantation correlated with inferior OS. Long-term outcomes of rrHL patients undergoing ASCT in India match those from the developed world in the era of peripheral blood stem cell transplantation. Pre-transplant performance status, chemo-sensitivity of disease, serum albumin and post-transplant remission status determined survival in our cohort
Editorial - A message from the editorial team for 2024.
No full textWe hope that the post-pandemic year 2023 has helped
regain a sense of normality in the scientific community and
has allowed all researchers to continue their scientific
endeavors with renewed enthusiasm. Hopefully, this will
continue this coming year, and thus, the editorial team from
the Journal of Macromolecular Science
Pyrolysis free out‐of‐plane co‐single atomic sites in porous organic photopolymer stimulates solar‐powered CO<sub>2</sub> fixation
No full textHerein, a facile strategy is illustrated to develop pyrolysis-free out-of-plane coordinated single atomic sites-based M-POP via a one-pot Friedel Craft acylation route followed by a post-synthetic metalation. The optimized geometry of the Co@BiPy-POP clearly reveals the presence of out-of-plane Co-single atomic sites in the porous backbone. This novel photopolymer Co@BiPy-POP shows extensive Π-conjugations followed by impressive light harvesting ability and is utilized for photochemical CO2 fixation to value-added chemicals. A remarkable conversion of styrene epoxide (STE) to styrene carbonate (STC) (≈98%) is obtained under optimized photocatalytic conditions in the existence of promoter tert-butyl ammonium bromide (TBAB). Synchrotron-based X-ray adsorption spectroscopy (XAS) analysis reveals the single atom coordination sites along with the metal (Co) oxidation number of +2.16 in the porous network. Moreover, in situ diffuse reflectance spectroscopy (DRIFTS) and electron paramagnetic resonance (EPR) investigations provide valuable information on the evolution of key reaction intermediates. Comprehensivecomputational analysis also helps to understand the overall mechanistic pathway along with the interaction between the photocatalyst and reactants. Overall, this study presents a new concept of fabricating porous photopolymers based on a pyrolysis-free out-of-plane-coordination strategy and further explores the role of single atomic sites in carrying out feasible CO2 fixation reactions
Morphology and phase-controlled synthesis of defect-rich layered cobalt hydroxide nanostructures for the oxygen evolution reaction
No full textThe morphology of nanomaterials plays an important role in catalysis and other applications. Herein, we demonstrate that not only the morphology but also the crystal phase of the nanomaterial plays significant roles. A single-step synthesis of α- and β-Co(OH)2 with a unique morphology is demonstrated, and their oxygen evolution reaction (OER) activity is presented. Nanocone-like α-Co(OH)2 and hexagonal plate-like β-Co(OH)2 nanostructures are obtained by a facile reflux method using a structure-regulating reagent to control the morphology. α-Co(OH)2 exhibits a small overpotential of 307 mV, which is 50 mV lower than that of β-Co(OH)2 to achieve a current density of 10 mA cm–2 for OER. Tafel slopes of 56 and 69 mV dec–1 with electrochemical active surface areas of 25 and 3.25 cm2 are estimated with α- and β-Co(OH)2, respectively. The superior OER activity of α-Co(OH)2 nanocones is attributed to their unique morphology and oxygen vacancy defects. The overall water splitting is demonstrated in a two-electrode system in an alkaline medium using α-Co(OH)2 as an OER electrocatalyst and Pt/C as a hydrogen evolution electrocatalyst. An overall voltage of 1.58 V at 10 mA cm–2 is obtained with the two-electrode system, with excellent durability for the water-splitting application