Publications by authors named "Giri R"

We report a Ni-catalyzed vicinal alkylarylation of unactivated alkenes in γ,δ- and δ,ε-alkenylamines with aryl halides and alkylzinc reagents. The reaction is enabled by amine coordination and can use all primary, secondary, and tertiary amines. The reaction constructs two new C(sp)-C(sp) and C(sp)-C(sp) bonds and produces δ- and ε-arylamines with C(sp)-branching at the γ- and δ-positions.

View Article and Find Full Text PDF
Article Synopsis
  • The study presents a new method for photoredox carbobromination that allows the reaction of unactivated alkenes with α-bromocarbonyl compounds using blue LED light.
  • It successfully utilizes various compounds like α-bromoesters and α-bromonitriles to produce alkylated alkenes from different types of alkenes, including terminal and disubstituted ones.
  • The mechanism of this reaction follows a radical-addition radical-pairing (RARP) pathway, where the key step involves the interaction of bromine radicals and alkyl radicals instead of traditional carbocation mechanisms.
View Article and Find Full Text PDF

Graphene and its derivatives, such as graphene oxide (GO) and reduced graphene oxide (rGO), have propelled advancements in biosensor research owing to their unique physicochemical and electronic characteristics. To ensure their safe and effective utilization in biological environments, it is crucial to understand how these graphene-based nanomaterials (GNMs) interact with a biological milieu. The present study depicts GNM-induced structural changes in a self-assembled phospholipid monolayer formed at an air-water interface that can be considered to represent one of the leaflets of a cellular membrane.

View Article and Find Full Text PDF

Despite being mostly neglected in structural biology, the C-terminal Regions (CTRs) are studied to be multifunctional in humans as well as in viruses. Previously, SARS-CoV-2 Spike and NSP1 proteins' CTRs are observed to be disordered, and experimental evidence showed a gain of structure properties in different physiological environments. In this line, we have investigated the structural dynamics of CTR (residues 38-61) of SARS-CoV-2 ORF6 protein, disrupting bidirectional transport between the nucleus and cytoplasm.

View Article and Find Full Text PDF

Acne vulgaris (AV) is a common dermatological condition that ranges from mild comedones to severe inflammatory nodules and scarring. Effective management is essential for improving patients' quality of life. The recent FDA approval of IDP-126 (Cabtreo™), a novel triple-combination gel, meets these needs by combining clindamycin phosphate, benzoyl peroxide, and adapalene into a single formulation.

View Article and Find Full Text PDF

Prostate cancer (PC) is among the most prevalent cancers in males. It is the leading cause of death in men, in around 48 out of 185 countries. Increased androgen receptor (AR) activity is the key factor contributing to the development or progression of newly diagnosed cases of prostate cancer.

View Article and Find Full Text PDF

While the dominant patterns of migration for livelihood among the poor in India are rural-to-rural and circular, literature on the health implications of child migration has largely focused on rural-to-urban, permanent movement. We compared child growth across three migration typologies rural Bihar: circular migrant families that repeatedly migrate to rural destination sites with accompanying young children, rural households with male migrants, and rural households that do not engage in migration. We integrated network theory based on caste and tribe geography to inform our analytical approach.

View Article and Find Full Text PDF

The growing demand for chemical production continues to drive the development of sustainable and efficient methods for introducing molecular complexity. In this context, the exploration of unconventional functional group transfer reagents (FGTRs) has led to significant advancements in practical and atom-efficient synthetic protocols. Aiming to advance the field of valuable organic synthesis, herein we report the successful development of carbon-based, bench-stable, modular, and inexpensive reagents implemented in dual halogen transfer to unsaturated hydrocarbons via photocatalytic activation of reagents based on a radical-polar crossover mechanism.

View Article and Find Full Text PDF

Antimicrobial-resistant bacteria pose a significant threat to humans, prompting extensive research into developing new antimicrobial peptides (AMPs). The biomembrane is the first barrier of a biological cell, hence, comprehending the interaction and self-assembly of AMPs in and around such membranes is of great importance. In the present study, several biophysical techniques have been applied to explore the self-assembly of ubiquicidin (29-41), an archetypical AMP, in and around the phospholipid monolayers formed at air-water interface.

View Article and Find Full Text PDF
Article Synopsis
  • * Common intraoperative ventilation methods include cross-table ventilation, veno-venous extra-corporeal membrane oxygenation, and cardiopulmonary bypass; however, cardiopulmonary bypass is usually avoided due to its complications and limitations in oncological surgery.
  • * The text introduces a novel technique for minimally invasive robotic carinal reconstruction that utilizes cross-table ventilation, alongside a video tutorial detailing the surgical process for a young patient with a mediastinal tumor invading the carina.
View Article and Find Full Text PDF

Background And Rationale: Febrile neutropenia (FN) is one of the major causes of early mortality among children undergoing induction chemotherapy for haematological malignancies. FN occurs in up to 80 % of the children undergoing intensive chemotherapy and FN specific mortality is as high as 10 %. The management of high-risk FN (HR-FN) is by early initiation of broad-spectrum empirical antibiotic therapy (EAT) which is continued till blood count recovery.

View Article and Find Full Text PDF

Copper tin sulphide (CuSnS) (CTS) has emerged as a potent material for applications in photovoltaic, thermoelectric, electrochemical, biological, and other fields. CTS has superior properties such as non-toxicity, direct bandgap, p-type conductivity, variable crystal structure, alterable morphology and ease of synthesis, and it is a better substitute for conventional semiconductor materials. In the present work, CTS crystals were grown using direct vapour transport.

View Article and Find Full Text PDF

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome with a variable presentation. We present a case of a 55-year-old female who presented with pain in the bilateral hip region for the last two years. On routine biochemical evaluation, she was found to have hypophosphatemia with an X-ray of the bilateral hip region showing an acute stress fracture in the bilateral intertrochanteric region of the femur.

View Article and Find Full Text PDF

We demonstrate that 2-alkenylarylaldimines and ketimines undergo thermal 6π-azaelectrocyclization to generate a wide range of azabicyclic o-quinodimethanes (o-QDMs). These o-QDMs exist as a hybrid of a diene and a benzylic diradical. The diradical nature was confirmed by their ability to undergo dimerization and react with H-atom donor, 2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) and O.

View Article and Find Full Text PDF

Herein we present our studies on the solvent-controlled difunctionalization of alkenes utilizing chlorodifluoroacetic acid (CDFA) and α-halo carboxylic acids for the synthesis of γ-lactones, γ-lactams and α,α-difluoroesters. Mechanistic insights revealed that photocatalytic reductive mesolytic cleavage of the C-X bond delivers elusive α-carboxyl alkyl radicals. In the presence of an olefin molecule, this species acts as a unique bifunctional intermediate allowing for stipulated formation of C-O, C-N and C-H bonds on Giese-type adducts single electron transfer (SET) or hydrogen atom transfer (HAT) events.

View Article and Find Full Text PDF

Tissue tension encompasses the mechanical forces exerted on solid tissues within animal bodies, originating from various sources such as cellular contractility, interactions with neighboring cells and the extracellular matrix. Emerging evidence indicates that an imbalance in such forces can influence structural organization, homeostasis, and potentially contribute to disease. For instance, heightened tissue tension can impede apical cell extrusion, leading to the retention of apoptotic or transformed cells.

View Article and Find Full Text PDF

Light-induced vicinal dibromination of unactivated alkenes and alkynes has been demonstrated by using methyl α-bromoacetate as a mild brominating agent. A near-visible light (370 nm) light-emitting diode (LED) mediates this simple dibromination reaction under mild conditions with the inexpensive and nontoxic α-bromoacetate. The reaction proceeds well with both terminal and internal alkenes and alkynes and those contained in N/O-heterocycles, indicating its versatility in synthesizing dibrominated organic compounds.

View Article and Find Full Text PDF

Understanding and controlling the structure and function of liquid interfaces is a constant challenge in biology, nanoscience and nanotechnology, with applications ranging from molecular electronics to controlled drug release. X-ray reflectivity and grazing incidence diffraction provide invaluable probes for studying the atomic scale structure at liquid-air interfaces. The new time-resolved laser system at the LISA liquid diffractometer situated at beamline P08 at the PETRA III synchrotron radiation source in Hamburg provides a laser pump with X-ray probe.

View Article and Find Full Text PDF

The functionality and efficiency of proteins within a biological membrane are highly dependent on both the membrane lipid composition and the physiochemical properties of the solution. Lipid mesophases are directly influenced by changes in temperature, pH, water content or due to individual properties of single lipids such as photoswitchability. In this work, we were able to induce light- and temperature-driven mesophase transitions in a model membrane system containing a mixture of 1,2-dipalmitoyl-phosphatidylcholine phospholipids and azobenzene amphiphiles.

View Article and Find Full Text PDF

Background: Prion diseases are transmissible and fatal neurodegenerative diseases characterized by accumulation of misfolded prion protein isoform (PrP), astrocytosis, microgliosis, spongiosis, and neurodegeneration. Elevated levels of cell membrane associated PrP protein and inflammatory cytokines hint towards the activation of death receptor (DR) pathway/s in prion diseases. Activation of DRs regulate, either cell survival or apoptosis, autophagy and necroptosis based on the adaptors they interact.

View Article and Find Full Text PDF

The conventional theory linking a single gene with a particular disease and a specific drug contributes to the dwindling success rates of traditional drug discovery. This requires a substantial shift focussing on contemporary drug design or drug repurposing, which entails linking multiple genes to diverse physiological or pathological pathways and drugs. Lately, drug repurposing, the art of discovering new/unlabelled indications for existing drugs or candidates in clinical trials, is gaining attention owing to its success rates.

View Article and Find Full Text PDF

The role of noncoding RNA has made remarkable progress in understanding progression, metastasis, and metastatic castration-resistant prostate cancer (mCRPC). A better understanding of the miRNAs has enhanced our knowledge of their targeting mainly at the therapy level in solid tumors, such as prostate cancer (PCa). microRNAs (miRNAs) belong to a class of endogenous RNA that deficit encoded proteins.

View Article and Find Full Text PDF

We disclose a Ni-catalyzed cyclization/alkylmetal interception reaction in which products are readily linearized to permit regiodefined alkene dicarbofunctionalization. This method offers a convenient route to access 1,2-oxasilolane heterocycles, 3-hydroxysilanes and 4-arylalkanols with the formation of C(sp)-C(sp) bonds at primary and secondary alkyl carbon centers. In this reaction, a silicon-oxygen (Si-O) bond functions as a detachable linker that can be delinked with several hydride, alkyl, aryl and vinyl nucleophiles to create profusely functionalized 3-hydroxysilanes.

View Article and Find Full Text PDF

We disclose a method for the dibenzylation of alkenylarenes with benzyl bromides using iron powder. This reaction generates branched alkyl scaffolds adorned with functionalized aryl rings through the formation of two new C(sp)-C(sp) bonds at the vicinal carbons of alkenes. This protocol tolerates electron-rich, electron-neutral, and electron-poor benzyl bromides and alkenylarenes.

View Article and Find Full Text PDF