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Surface tailoring-modulated bifunctional oxygen electrocatalysis with CoP for rechargeable Zn–air battery and water splitting
No full textThe transition metal phosphide (TMP)-based functional electrocatalysts are very promising for the development of electrochemical energy conversion and storage devices including rechargeable metal–air batteries and water electrolyzer. Tuning the electrocatalytic activity of TMPs is one of the vital steps to achieve the desired performance of these energy devices. Herein, we demonstrate the modulation of the bifunctional oxygen electrocatalytic activity of nitrogen-doped carbon-encapsulated CoP (CoP@NC) nanostructures by surface tailoring with ultralow amount (0.56 atomic %) of Ru nanoparticles (2.5 nm). The CoP at the core and the Ru nanoparticles on the shell have a facile charge transfer interaction with the encapsulating NC. The strong coupling of Ru with CoP@NC boosts the electrocatalytic performance toward oxygen reduction (ORR), oxygen evolution (OER), and hydrogen evolution (HER) reactions. The surface-tailored catalyst requires only 35 mV to deliver the benchmark current density of 10 mA⋅cm–2 for HER. A small potential gap of 620 mV between ORR and OER is achieved, making the catalyst highly suitable for the development of rechargeable zinc–air batteries (ZABs). The homemade ZAB delivers a specific capacity of 780 mA⋅hgZn–1 and peak power density of 175 mW⋅cm–2 with a very small voltaic efficiency loss (1.1%) after 300 cycles. The two-electrode water splitting cell (CoP@NC-Ru||CoP@NC-Ru) delivers remarkably low cell voltage of 1.47 V at the benchmark current density. Stable current density of 25 mA⋅cm–2 for 25 h without any significant change is achieved. Theoretical studies support the charge transfer interaction-induced enhanced electrocatalytic activity of the surface-tailored nanostructure
Primary Ewing’s Sarcoma affecting the Central Nervous System: A single-center experience and Narrative review
No full textBackground and objectives
Ewing’s sarcoma (EWS) is a malignant round-cell tumor arising from the bone and soft tissue. It is a disease of children and young adults. EWS affecting the central nervous system (cranial and spinal column) is relatively rare with an annual incidence of approximately one case per million in the Western population. Due to their rarity, very few studies are available in the literature. We present our experience of managing 21 such cases, highlighting their clinical, and radiological findings, treatment strategy, and surgical outcomes in patients with primary EWS affecting the central nervous system.
Materials and methods
We retrospectively collected hospital records of patients with primary EWS affecting the CNS (cranial and spinal column), who had been surgically treated in our Neuroscience Center between 2015 and 2023. Patients’ demographics, presentation, radiological findings, treatment strategy including surgery and biopsy followed by adjuvant therapy, and outcome at discharge, and the latest follow-up were analyzed from our database.
Results
There were sixteen male and five female patients with a mean age of 18.22 ± 12.73 years (ranging from 6 months to 59 years). The commonest presentation was headache and vomiting in cranial lesions (5/13 patients, 38.46%), and back pain in spinal lesions (4/8 patients, 50%). The site of lesions was cranial in thirteen patients (61.9%) and spinal column in eight patients (38.1%). The commonest site was the frontal region in the cranial group (6 patients, 46.15%) and the lumbar region in the spinal group (4 patients, 50%). All patients underwent surgical intervention [tumor resection (18) and biopsy (3)]. Tumor resection was achieved in 18 patients (85.71%). The extent of resection was gross-total excision in 9 patients (42.86%), near-total excision in 5 patients (23.8%), and tumor decompression in 4 patients (19%). Four patients underwent spinal instrumentation. Fifteen patients (71.42%) received multiagent chemo-radiotherapy according to institute protocol. Five patients (23.8%) with poor KPS expired within 6 months of surgery and could not receive adjuvant therapy. Two patients (9.52%) improved symptomatically, and nine patients (42.86%) remained asymptomatic at a mean follow-up of 25.1 ± 29 months. One patient (4.76%) after receiving 2 cycles of adjuvant therapy had initial improvement but expired later due to disease progression. Four patients after adjuvant chemo-radiotherapy (19%) expired due to systemic spread.
Conclusion
Primary EWS affecting the central nervous system is a rare variety. A detailed radiological assessment can aid in adequate planning for safe maximal resection. Timely tissue diagnosis is essential for initiating early treatment. Radical excision followed by adjuvant therapy offers a favorable outcome. Postoperative adjuvant chemo-radiotherapy aids in optimal disease control and surgical outcome. With the current treatment strategy, good surgical outcomes can be achieved. However, metastasis is not uncommon and should be evaluated regularly
Regulating the twisted intramolecular charge transfer and anti-heavy atom effect at supramolecular level for favorable photosensitizing activity in water
No full textPhotosensitizing assemblies based on twisted intramolecular charge transfer (TICT) active donor–acceptor–donor (D-A-D) system BrTPA-Qx having bromine atoms at the periphery have been developed. Through strategic incorporation of bromine atoms at the para-position to the nitrogen–carbon bonds of phenyl rings at the periphery, halogen–halogen interactions are induced in BrTPA-Qx nanoassemblies in H2O:DMSO (99:1) solution. Hence, the anti-heavy atom effect is induced, and the limitations of TICT (dark excited state) and heavy atom effect (triplet deactivation via radiative decay) could be overcome. Because of TICT and anti-heavy atom effect, supramolecular BrTPA-Qx nanoassemblies demonstrate high efficiency in promoting activation of aerial oxygen via electron and energy transfer pathways in aqueous media. The significant influence of the stabilized TICT state and anti-heavy-atom effect in controlling the ROS generation was validated through in-depth solvent-dependent photophysical studies and investigations of the structure–activity relationship in several model compounds. The notable photosensitizing activity of BrTPA-Qx nanoassemblies is manifested in their ability to efficiently catalyze the oxidative coupling of benzylamine (via type I and type II mechanisms), Knoevenagel condensation of aromatic aldehydes (type II), and oxidative hydroxylation of arylboronic acids (type I) under mild conditions
124P Targeting neoantigens in chronic lymphocytic leukemia (CLL) for personalized T cell therapy
No full textBackground:
Cancer cells are known to express unique tumor associated antigens (TAA) or novel neoantigens (NeoAg). The latter arise from somatic mutations (SNPs, ins/dels, frameshifts, neoORFs). Such antigens are considered as potential targets of T cell therapy & were investigated in CLL using paired whole exome (WES) & transcriptome (WTS) next generation sequencing (NGS) in this study. The main aim of this study was to identify TAA / personalized NeoAgs in CLL patients for T cell therapy using NGS approach.
Methods:
This study was approved by the institute’s ethics committee. WES (Twist Whole Exome library prep kit) & WTS (NEB Ultra II directional RNA-Seq Library Prep kit) on Illumina NovaSeq6000 was performed on malignant CLL B cells (CD45+CD19+CD5+) & paired Neutrophils (CD45+CD15+CD16+CD56-) in 51 CLL patients. Data was processed with in-house neoantigen discovery pipeline that identified somatic variants, differential expression, predicted HLA– neopeptide binding & coanalyzed TCR CDR3 motifs.
Results
The topmost highly expressed genes in CLL included FMOD, SFTPB, IGSF3 that could be considered as putative TAAs & explored further. Several somatic mutations were identified in TP53(8%), SF3B1(19%), NOTCH1(15%), CHD2(6%) & others. Further analysis revealed a series of HLA-A2 restricted putative neoepitopes derived from C16ORF57, FNDC3B, SF3B1, NFKB1E & other NeoAgs. The NFKB1E neoepitope, for example, originated from a frameshift deletion in exon 1 in two patients & was predicted to be restricted not only by HLA-A*02:11 (most common A2 allele in North Indians) but also other versatile subtypes A*02:01 (Caucasian, Gambian, Japanese) /*02:02 (Gambian) /*02:05 (Gambian, N Indians) /*02:06 (Japanese) /*02:07 (Japanese, N Indians). The CD8+T cell TCRαβ CDR3 motifs were also coanalyzed in these patients.
Conclusions
Immunogenic potential of TAA & NeoAgs identified in this study warrant further investigations & could offer promising personalized immunotherapeutic approach for treatment of CLL. Activation of NeoAg specific cytotoxic T cells in conjunction with checkpoint blockage/ CART/ adjuvants/ conventional therapies could augment anti tumor immune responses. Acknowledgements ICMR 2020-0012, 5/13/4/2020/NCD-III for funding
MCL-063 clinical characteristics and survival outcomes of patients with mantle cell lymphoma—a North Indian Tertiary care center experience
No full textContext:
Mantle cell lymphoma (MCL) is an aggressive variant of non-Hodgkin lymphoma. Indian data is scarce owing to its rarity in Southeast Asia.
Objective:
Assess if rituximab maintenance (RM) improves overall survival (OS) of MCL patients.
Study Design:
We analyzed ambispective clinical data of 90 transplant-ineligible MCL patients treated between January 2013 and December 2023 at IRCH-AIIMS, New Delhi, India. Rituximab-based induction was used in all patients as per institutional protocol. Due to financial constraints, RM was used in 28 patients (31.0%). Primary outcome was OS. Secondary outcome was event-free survival (EFS). Response was assessed by modified Cheson's lymphoma response evaluation criteria. STATA 13.0 was used to assess survival by Kaplan-Meier analysis and log-rank test. Effect of RM on OS and EFS was adjusted for other factors in multivariate analysis by Cox proportional hazards model, then expressed as adjusted hazard ratio (aHR), 95% CI. P value <.05 defined statistical significance.
Results:
Median age 60 years; male-female ratio 3:1. Seventy-nine (88.0%) had generalized lymphadenopathy, 72 (80.0%) extra-nodal involvement, 49 (54.0%) B symptoms, 34 (38.0%) ECOG PS ≥2, 84 (93.0%) advanced stage (III/IV), 49 (54.0%) high-risk MIPI at presentation. Clinical and tumor characteristics and response rates after initial induction were similar in both RM and non-RM groups. Overall, 52 (58.0%) patients were alive with median follow-up of 63.0 months. Median OS was 37.5 months in the non-RM group and not reached in the RM group. In RM vs non-RM groups, the estimated 1-, 2-, and 3-year OS were 100.0%, 91.0%, and 81.0% vs 75.0%, 63.0%, and 55.0%, respectively. RM was significantly associated with better OS (aHR [95%CI]: 0.31 [0.13-0.75], P=.01). ECOG PS ≥2 was associated with poor OS (aHR [95%CI]: 2.41 [1.14-5.08], P=.02). Median EFS was significantly lower in non-RM group (14.0 vs 42.5 months; aHR [95%CI]: 0.34 [0.18-0.64], P=.001).
Conclusions:
This was the first study from Southeast Asia to demonstrate the impact of RM in MCL. RM significantly improved the OS and EFS of MCL patients. However, randomized controlled trials are needed to concretize the evidence of OS benefit
Methionine biosynthetic genes and methionine sulfoxide reductase A are required for <i>Rhizoctonia solani</i> <scp>AG1‐IA</scp> to cause sheath blight disease in rice
No full textRhizoctonia solani is a polyphagous necrotrophic fungal pathogen that causes sheath blight disease in rice. It deploys effector molecules as well as carbohydrate-active enzymes and enhances the production of reactive oxygen species for killing host tissues. Understanding R. solani ability to sustain growth under an oxidative-stress-enriched environment is important for developing disease control strategies. Here, we demonstrate that R. solani upregulates methionine biosynthetic genes, including Rs_MET13 during infection in rice, and double-stranded RNA-mediated silencing of these genes impairs the pathogen's ability to cause disease. Exogenous treatment with methionine restores the disease-causing ability of Rs_MET13-silenced R. solani and facilitates its growth on 10 mM H2O2-containing minimal-media. Notably, the Rs_MsrA gene that encodes methionine sulfoxide reductase A, an antioxidant enzyme involved in the repair of oxidative damage of methionine, is upregulated upon H2O2 treatment and also during infection in rice. Rs_MsrA-silenced R. solani is unable to cause disease, suggesting that it is important for the repair of oxidative damage in methionine during host colonization. We propose that spray-induced gene silencing of Rs_MsrA and designing of antagonistic molecules that block MsrA activity can be exploited as a drug target for effective control of sheath blight disease in rice
Larval growth rate is not a major determinant of adult wing shape and eyespot size in the seasonally polyphenic butterfly <i>Melanitis leda</i>
No full textBackground
Insects often show adaptive phenotypic plasticity where environmental cues during early stages are used to produce a phenotype that matches the environment experienced by adults. Many tropical satyrine butterflies (Nymphalidae: Satyrinae) are seasonally polyphenic and produce distinct wet- and dry-season form adults, providing tight environment-phenotype matching in seasonal environments. In studied Mycalesina butterflies, dry-season forms can be induced in the laboratory by growing larvae at low temperatures or on poor food quality. Since both these factors also tend to reduce larval growth rate, larval growth rate may be an internal cue that translates the environmental cues into the expression of phenotypes. If this is the case, we predict that slower-growing larvae would be more likely to develop a dry-season phenotype.
Methods
We performed the first experimental study on seasonal polyphenism of a butterfly in the tribe Melanitini. We measured both larval growth rate and adult phenotype (eyespot size and wing shape) of common evening brown butterflies (Melanitis leda), reared at various temperatures and on various host-plant species. We constructed provisional reaction norms, and tested the hypothesis that growth rate mediates between external cues and adult phenotype.
Results
Reaction norms were similar to those found in Mycalesina butterflies. We found that both among and within treatments, larvae with lower growth rates (low temperature, particular host plants) were more likely to develop dry-season phenotypes (small eyespots, falcate wing tips). However, among temperature treatments, similar growth rates could lead to very different wing phenotypes, and within treatments the relationships were weak. Moreover, males and females responded differently, and eyespot size and wing shape were not strongly correlated with each other. Overall, larval growth rate seems to be weakly related to eyespot size and wing shape, indicating that seasonal plasticity in M. leda is primarily mediated by other mechanisms
Superfluorescence from Electron-Hole Plasma at Moderate Temperatures of 175 K
No full textSuperfluorescence, a cooperative coherent spontaneous emission, is of great importance to the understanding of many-body correlation in optical processes. Even though superfluorescence has been demonstrated in many diverse systems, it is hard to observe in electron-hole plasma (EHP) due to its rapid dephasing and hence needs strong magnetic fields or complex microcavities. Herein, we report the first experimental observation of superfluorescence from EHP up to a moderate temperature of 175 K without external stimuli in a coupled metal halide perovskite quantum dots film. The EHP exhibits macroscopic quantum coherence through spontaneous synchronization. The coherence of the excited state decays by superfluorescence, which is redshifted 40 meV from the spontaneous emission with a ∼1700 times faster decay rate and exhibits quadratic fluence dependence. Notably, the excited state population’s delayed growth and abrupt decay, which are strongly influenced by the pump fluence and the Burnham-Chiao ringing, are the characteristics of the superfluorescence. Our findings will open up a new frontier for cooperative emission and light beam–based technologies
Projected change in precipitation and temperature over undivided Sudan and its major cities
No full textThis study investigates the trend in the projected rainfall and temperature over undivided Sudan and its major cities of political, trade, and agricultural significance under two different Representative Concentration Pathways (RCPs; RCP2.6 and RCP8.5). Available high-resolution datasets from the Coordinated Regional Climate Downscaling Experiment- Coordinated Output for Regional Evaluations (CORDEX-CORE) at a resolution of 25 km along with their ensemble are considered. The study analyzes projected climate conditions, with a specific emphasis on the near future (2036–2060) and far future (2071–2095). The rainfall distribution is projected to decline across South Sudan (undivided Sudan) under RCP2.6 (RCP8.5). The projected temperature is significantly increasing while rainfall is decreasing across all cities, with these trends being more pronounced under the RCP8.5 scenario. These changes could potentially result in various climate extremes such as severe heatwaves, droughts, and wildfires, which could have significant impacts on the ecosystems, agriculture, public health and ultimately, the livelihood and socio-economic condition of the people. The findings of the study will assist the governments, local administration and town planners in formulating short-term and long-term strategies for adaptation and mitigation, aimed at reducing the impacts of climate change. The study suggests specific measures to address the extreme heat and water deficit at the local scale, hence making it a valuable policy document for addressing the changing climate in undivided Sudan
Himalayan Re-gridded and Observational Experiment (HiROX): Part I – Development
No full textThe present work serves as a theoretical commentary over the Himalayan Re-gridded and Observational EXperiment (HiROX) and distributes the conceived framework grown under the two-phase experiment. HiROX is a scientific effort aimed at revising the existing precipitation knowledge over the Central Himalayas over the state of Uttarakhand, including the Upper Ganga Basin. The first phase of the study is experimenting with machine learning methods aimed at developing re-gridded precipitation datasets capable of incorporating selective precipitation features and distributing the developed machine learning framework to the research community. The model is designed for easy reproduction of re-gridded precipitation data and the ability to adapt to the available precipitation datasets subject to missing and/or modified inputs. The model is capable of ingesting gridded precipitation datasets at varying spatial resolutions, along with point data values, and can return gridded precipitation information at a spatial resolution of 5 × 5 km2. The second objective of the companion paper under HiROX is the realization of the features of the developed model and exercising it in the development of two high-resolution precipitation datasets at daily timesteps, namely HiROX-1 (~50 yrs) and HiROX-2 (~20 yrs). The present paper limits the discourse to robust development, and the produced datasets are discussed and distributed in the joint paper – Himalayan Re-gridded and Observational Experiment (HiROX): Part II – Application