Substrate NOBINAc ligand affinity for Pd-catalyzed enantioselective C-H activation over reactive β-C-H bonds in ferrocenyl amines.

Ferrocenyl amines as directing groups for C-H activation have limitations as they are prone to undergo oxidation, allylic deamination, and β-hydride elimination. The fundamental challenge observed here is the competition between the desired C-H activation the vulnerable β-C-H bond activation of amines and fine-tuning of a suitable oxidant which avoids the oxidation of the β-C-H bond and ferrocene. Herein, the potential of an axially chiral NOBINAc ligand is revealed to implement the enantioselective Pd-catalyzed C-H activation process of ferrocenyl amines.

Three positively charged binding sites on the eastern equine encephalitis virus E2 glycoprotein coordinate heparan sulfate- and protein receptor-dependent infection.

Naturally circulating strains of eastern equine encephalitis virus (EEEV) bind heparan sulfate (HS) receptors and this interaction has been linked to its neurovirulence. Previous studies associated EEEV-HS interactions with three positively charged amino acid clusters on the E2 glycoprotein. One of these sites has recently been reported to be critical for binding EEEV to very-low-density lipoprotein receptor (VLDLR), an EEEV receptor protein.

Evaluating non-photochemical quenching (NPQ) kinetics and photosynthetic efficiency in cassava () subjected to variable high light conditions.

Light intensity is a critical environmental factor influencing plant growth and development. To survive high light conditions, plants have evolved various protective mechanisms, including non-photochemical quenching (NPQ). However, NPQ can limit effective photosynthetic yield when transitioning to low light conditions.

Evaluation of potential increase in photosynthetic efficiency of cassava ( Crantz) plants exposed to elevated carbon dioxide.

Cassava (Manihot esculenta Crantz), an important tropical crop, is affected by extreme climatic events, including rising CO2 levels. We evaluated the short-term effect of elevated CO2 concentration (ECO2 ) (600, 800 and 1000ppm) on the photosynthetic efficiency of 14 cassava genotypes. ECO2 significantly altered gaseous exchange parameters (net photosynthetic rate (P n ), stomatal conductance (g s ), intercellular CO2 (C i ) and transpiration (E )) in cassava leaves.

Mucosal vaccine-induced cross-reactive CD8 T cells protect against SARS-CoV-2 XBB.1.5 respiratory tract infection.

A nasally delivered chimpanzee adenoviral-vectored severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine (ChAd-SARS-CoV-2-S) is currently used in India (iNCOVACC). Here, we update this vaccine by creating ChAd-SARS-CoV-2-BA.5-S, which encodes a prefusion-stabilized BA.

Immunoglobulin replacement products protect against SARS-CoV-2 infection in vivo despite poor neutralizing activity.

Immunoglobulin (IG) replacement products are used routinely in patients with immune deficiency and other immune dysregulation disorders who have poor responses to vaccination and require passive immunity conferred by commercial antibody products. The binding, neutralizing, and protective activity of intravenously administered IG against SARS-CoV-2 emerging variants remains unknown. Here, we tested 198 different IG products manufactured from December 2019 to August 2022.

The many ways in which alphaviruses bind to cells.

Only a subset of viruses can productively infect many different host species. Some arthropod-transmitted viruses, such as alphaviruses, can infect invertebrate and vertebrate species including insects, reptiles, birds, and mammals. This broad tropism may be explained by their ability to engage receptors that are conserved across vertebrate and invertebrate classes.

A broadly reactive antibody targeting the N-terminal domain of SARS-CoV-2 spike confers Fc-mediated protection.

Most neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) target the receptor binding domain (RBD) of the spike (S) protein. Here, we characterize a panel of mAbs targeting the N-terminal domain (NTD) or other non-RBD epitopes of S. A subset of NTD mAbs inhibits SARS-CoV-2 entry at a post-attachment step and avidly binds the surface of infected cells.

Vertebrate-class-specific binding modes of the alphavirus receptor MXRA8.

MXRA8 is a receptor for chikungunya (CHIKV) and other arthritogenic alphaviruses with mammalian hosts. However, mammalian MXRA8 does not bind to alphaviruses that infect humans and have avian reservoirs. Here, we show that avian, but not mammalian, MXRA8 can act as a receptor for Sindbis, western equine encephalitis (WEEV), and related alphaviruses with avian reservoirs.

Coordination Behavior of the Tellurium Incorporated Mercuraazametallamacrocycle and Investigation of d ⋅⋅⋅d Interactions between Closed Shell (Ag Hg ) Metal Ions.

Herein, a new tellurium and mercury containing mercuraazametallamacrocycle has been prepared via (2+2) condensation of bis(o-aminophenyl)telluride and bis(o-formylphenyl)mercury(II). The isolated bright yellow solid of mercuraazametallamacrocycle has adopted unsymmetrical figure-of-eight conformation in the crystal structure. To study the metallophilic interactions between closed shell metal ions, the macrocyclic ligand has been treated with two equiv.

A chikungunya virus-like particle vaccine induces broadly neutralizing and protective antibodies against alphaviruses in humans.

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes epidemics of acute and chronic musculoskeletal disease. Here, we analyzed the human B cell response to a CHIKV-like particle-adjuvanted vaccine (PXVX0317) from samples obtained from a phase 2 clinical trial in humans (NCT03483961). Immunization with PXVX0317 induced high levels of neutralizing antibody in serum against CHIKV and circulating antigen-specific B cells up to 6 months after immunization.

Monitoring of Harmful Algal Bloom (HAB) of Noctiluca scintillans (Macartney) along the Gulf of Mannar, India using in-situ and satellite observations and its impact on wild and maricultured finfishes.

In the Gulf of Mannar, Noctiluca scintillans blooms have been observed three times in September 2019, September and October 2020, and October 2021. It was determined and measured how the bloom period affects ichthyo-diversity. Noctiluca cell density varied slightly from year to year, ranging from1.

Synthesis of cobalt(II) phenolate selenoether complexes to mimic hydrogenase-like activity for hydrogen gas production.

Selenium-derived electrocatalysts have been well explored for electrocatalytic hydrogen evolution reactions to mimic hydrogenase-like activity; however, the stability of these synthetic mimics is yet to be enhanced. In this study, we report the synthesis and characterization of a series of 1,10-phenanthroline-cobalt(II) phenolate selenoether complexes using 1,10-phenanthroline and 6-nitro-1,10-phenanthroline-Co(II)-dichloride and substituted bis-selenophenolate ligands. The synthesized cobalt(II) phenolate selenoether complexes have been characterized by CHN analysis, mass spectrometry, single crystal XRD, and UV-visible absorption spectroscopy.

mRNA vaccine boosting enhances antibody responses against SARS-CoV-2 Omicron variant in individuals with antibody deficiency syndromes.

Individuals with primary antibody deficiency (PAD) syndromes have poor humoral immune responses requiring immunoglobulin replacement therapy. We followed individuals with PAD after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination by evaluating their immunoglobulin replacement products and serum for anti-spike binding, Fcγ receptor (FcγR) binding, and neutralizing activities. The immunoglobulin replacement products tested have low anti-spike and receptor-binding domain (RBD) titers and neutralizing activity.

A base-free copper-assisted synthesis of -symmetric spirotelluranes and biaryls based on divergent stoichiometry of NaTe.

A one pot Cu(I)-assisted synthetic methodology has been developed for the preparation of biologically important -symmetric spirodiaza, benzyloxy and benzoxytelluranes from 2-bromo--aryl benzamides, benzyl alcohols, and benzoic acids by using the tellurium dianion (Te) under base-free conditions. Furthermore, C-C coupled biaryl 1,1'-diamides have been prepared by using an excess of NaTe under the same reaction conditions. The synthesized spirodiazatelluranes served as a potent catalyst for the reduction of HO and nitro-Michael reactions.

BCL6-dependent TCF-1 progenitor cells maintain effector and helper CD4 T cell responses to persistent antigen.

Soon after activation, CD4 T cells are segregated into BCL6 follicular helper (Tfh) and BCL6 effector (Teff) T cells. Here, we explored how these subsets are maintained during chronic antigen stimulation using the mouse chronic LCMV infection model. Using single cell-transcriptomic and epigenomic analyses, we identified a population of PD-1 TCF-1 CD4 T cells with memory-like features.