Smart Luminescent Materials for Emerging Sensors: Fundamentals and Advances.

Smart luminescent materials have drawn a significant attention owing to their unique optical properties and versatility in sensor applications. These materials, encompassing a broad spectrum of organic, inorganic, and hybrid systems including quantum dots, organic dyes, and metal-organic frameworks (MOFs), offer tunable emission characteristics that can be engineered at the molecular or nanoscale level to respond to specific stimuli, such as temperature, pH, and chemical presence. Recent advancements have been driven by the integration of nanotechnology, which enhances the sensitivity and selectivity of luminescent materials in sensor platforms.

Neural cells and their progenitors in regenerating zebrafish spinal cord.

The zebrafish (Danio rerio), among all amniotes is emerging as a powerful model to study vertebrate organogenesis and regeneration. In contrast to mammals, the adult zebrafish is capable of regenerating damaged axonal tracts; it can replace neurons and glia lost after spinal cord injury (SCI) and functionally recover. In the present paper, we report ultrastructural and cell biological analyses of regeneration processes after SCI.

Benzimidates as -Diamidation and Amidoindolyzation Cascade Synthons with a Hydrated Ni Catalyst.

We contributed a new benzimidate chemistry through moisture-insensitive Ni/Ni-Fe combo-catalysis for a simultaneous 2-3 bond-forming -diamidation and amidoindolyzation cascade reaction to construct symmetrical and unsymmetrical -(arylmethylene)amides and indolo(arylmethylene)amides, using emerging benzimidate synthons. The operational simplicity, mild nature, generality, and robustness of the strategy were validated through syntheses of a wide range of new molecules, labile sugar-based chiral compounds, and pharmaceuticals with high yields under the same reaction conditions.

Selective amidation by a photocatalyzed umpolung reaction.

A metal-catalyzed organic transformation merged with another organophotocatalyst has been developed under mild conditions for production of α-ketoamides. CuI-catalyzed highly selective and rapid COCH-amidation in the presence of electrophilic C[double bond, length as m-dash]O bonds, which is synchronized by an eosin Y (EY)-photocatalyst, furnishes a wide range of labile α-ketoamides, unsymmetrical oxalamides and chiral analogues on the treatment of 1,3-dicarbonyls with amines, PhIO and LED light at room temperature. The current strategy opens up a new avenue to making photocatalysis a common synthetic tool for large-scale production in academia and industry.

Axonal regeneration in zebrafish spinal cord.

In the present review we discuss two interrelated events-axonal damage and repair-known to occur after spinal cord injury (SCI) in the zebrafish. Adult zebrafish are capable of regenerating axonal tracts and can restore full functionality after SCI. Unlike fish, axon regeneration in the adult mammalian central nervous system is extremely limited.

Regeneration of Zebrafish CNS: Adult Neurogenesis.

Regeneration in the animal kingdom is one of the most fascinating problems that have allowed scientists to address many issues of fundamental importance in basic biology. However, we came to know that the regenerative capability may vary across different species. Among vertebrates, fish and amphibians are capable of regenerating a variety of complex organs through epimorphosis.

Human regeneration: An achievable goal or a dream?

The main objective of regenerative medicine is to replenish cells or tissues or even to restore different body parts that are lost or damaged due to disease, injury and aging. Several avenues have been explored over many decades to address the fascinating problem of regeneration at the cell, tissue and organ levels. Here we discuss some of the primary approaches adopted by researchers in the context of enhancing the regenerating ability of mammals.

Characterization of Proliferating Neural Progenitors after Spinal Cord Injury in Adult Zebrafish.

Zebrafish can repair their injured brain and spinal cord after injury unlike adult mammalian central nervous system. Any injury to zebrafish spinal cord would lead to increased proliferation and neurogenesis. There are presences of proliferating progenitors from which both neuronal and glial loss can be reversed by appropriately generating new neurons and glia.

Genome wide expression profiling during spinal cord regeneration identifies comprehensive cellular responses in zebrafish.

Background: Among the vertebrates, teleost and urodele amphibians are capable of regenerating their central nervous system. We have used zebrafish as a model to study spinal cord injury and regeneration. Relatively little is known about the molecular mechanisms underlying spinal cord regeneration and information based on high density oligonucleotide microarray was not available.

Expression pattern of Nogo-A, MAG, and NgR in regenerating urodele spinal cord.

Background: The mammalian central nervous system is incapable of substantial axon regeneration after injury partially due to the presence of myelin-associated inhibitory molecules including Nogo-A and myelin associated glycoprotein (MAG). In contrast, axolotl salamanders are capable of considerable axon regrowth during spinal cord regeneration.

Results: Here, we show that Nogo-A and MAG, and their receptor, Nogo receptor (NgR), are present in the axolotl genome and are broadly expressed in the central nervous system (CNS) during development, adulthood, and importantly, during regeneration.

CeCl3·7H2O catalyzed C-C and C-N bond-forming cascade cyclization with subsequent side-chain functionalization and rearrangement: a domino approach to pentasubstituted pyrrole analogues.

CeCl(3)·7H(2)O is found as an efficient catalyst for new intermolecular domino reactions of three-, four- and seven-component assemblies of common precursors under benign reaction conditions. Generation of enaminioesters from β-keto esters and primary amines, activation of their allylic sp(3) C-H, vinylic sp(2) C-H and N-H bonds, multi C-C and C-N bond-forming cascade cyclization with 1,2-diketones and subsequent side-chain alkylation have been developed to construct functionalized pentasubstituted pyrroles and their chiral analogues. The scope of the domino reaction is successfully explored toward synthesis of highly aryl-substituted pyrroles, pentasubstituted pyrroles bearing C2-olefinic side-chain and spiro-2-pyrrolinones and their chiral analogues via unusual side-chain amination, elimination and ring contraction.

Cellular response after crush injury in adult zebrafish spinal cord.

Zebrafish proves to be an excellent model system to study spinal cord regeneration because it can repair its disengaged axons and replace lost cells after injury, allowing the animal to make functional recovery. We have characterized injury response following crush injury, which is comparable to the mammalian mode of injury. Infiltrations of blood cells during early phases involve macrophages that are important in debris clearance and probably in suppression of inflammatory response.

Analysis of the expression and function of Wnt-5a and Wnt-5b in developing and regenerating axolotl (Ambystoma mexicanum) limbs.

Urodele amphibians are unique adult vertebrates because they are able to regenerate body parts after amputation. Studies of urodele limb regeneration, the key model system for vertebrate regeneration, have led to an understanding of the origin of blastema cells and the importance of positional interactions between blastema cells in the control of growth and pattern formation. Progress is now being made in the identification of the signaling pathways that regulate dedifferentiation, blastema morphogenesis, growth and pattern formation.