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Maintaining precise synaptic contacts between neuronal partners is critical to ensure the proper functioning of the mammalian central nervous system (CNS). Diverse cell recognition molecules, such as classic cadherins (Cdhs), are part of the molecular machinery mediating synaptic choices during development and synaptic maintenance. Yet, the principles governing neuron-neuron wiring across diverse CNS neuron types remain largely unknown. The retinotectal synapses, connections from the retinal ganglion cells (RGCs) to the superior collicular (SC) neurons, offer an ideal experimental system to reveal molecular logic underlying synaptic choices and formation. This is due to the retina's unidirectional and laminar-restricted projections to the SC and the large databases of presynaptic RGC subtypes and postsynaptic SC neuronal types. Here, we focused on determining the role of Type II Cdhs in wiring the retinotectal synapses. We surveyed Cdhs expression patterns at neuronal resolution and revealed that Cdh13 is enriched in the wide-field neurons in the superficial SC (sSC). In either the Cdh13 null mutant or selective adult deletion within the wide-field neurons, there is a significant reduction of spine densities in the distal dendrites of these neurons in both sexes. Additionally, Cdh13 removal from presynaptic RGCs reduced dendritic spines in the postsynaptic wide-field neurons. Cdh13-expressing RGCs use differential mechanisms than αRGCs and On-Off Direction-Selective Ganglion Cells (ooDSGCs) to form specific retinotectal synapses. The results revealed a selective transneuronal interaction mediated by Cdh13 to maintain proper retinotectal synapses in vivo.

Mild and inexpensive copper‐catalyzed aromatization‐driven ring‐opening amination and oxygenation of spiro dihydroquinazolinones are presented, respectively. These protocols provide facile and atom‐economical access to the aminated and the carbonyl‐containing quinazolin‐4(3H)‐ones in good yields with good functional group compatibility, which are difficult to obtain by conventional methods. Remarkably, a telescoped procedure involving the condensation and the ring‐opening/functionalization for simple cycloalkanone was found to be accessible. Mechanistic studies suggest a radical pathway for this transformation. [ABSTRACT FROM AUTHOR]

This study investigates the spatio-temporal evolution of agricultural carbon emission efficiency (ACEE) in China and its relationship with agricultural economic growth (AEG). The results indicate several findings: Firstly, between 2012 and 2021, China's agricultural carbon emission efficiency exhibited an upward trend, with the mean value increased from 0.349 to 0.807. Furthermore, the distribution pattern shifted from a dispersed, point-like distribution to an aggregated and continuous distribution. Secondly, the average agricultural carbon emission efficiency in China following a decreasing order: South China, Northwest China, Southwest China, East China, North China, Central China and Northeast China. Thirdly, the relationship between agricultural carbon emission efficiency and the agricultural economy in China has transitioned from weak decoupling to negative decoupling. Based on these findings, this study proposes some recommendations to enhance agricultural carbon emission efficiency and promote its decoupling from agricultural economic growth. These recommendations aim to achieve low-carbon and high-efficiency development of agriculture. [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament (ACL) injuries pose a significant challenge due to their limited healing potential, often resulting in premature arthritis. The factors and mechanisms contributing to this inadequate healing process remain elusive. During the acute phase of injury, ACL tissues express elevated periostin levels that decline over time. The functional significance of periostin in ligament biology remains understudied. In this study, we investigated the functional and mechanistic implications of periostin deficiency in ACL biology, utilizing ligament fibroblasts derived from patients and a murine model of ACL rupture. Our investigations unveiled that periostin knockdown compromised fibroblast growth characteristics, hindered the egress of progenitor cells from explants, and arrested cell‐cycle progression, resulting in the accumulation of cells in the G0/G1 phase and moderate apoptosis. Concurrently, a significant reduction in the expression of cell‐cycle and matrix‐related genes was observed. Moreover, periostin deficiency triggered apoptosis through STAT3Y705/p38MAPK signaling and induced cellular senescence through increased production of reactive oxygen species (ROS). Mechanistically, inhibition of ROS production mitigated cell senescence in these cells. Notably, in vivo data revealed that ACL in Postn−/− mice exhibited a higher tearing frequency than wild‐type mice under equivalent loading conditions. Furthermore, injured ACL with silenced periostin expression, achieved through nanoparticle‐siRNA complex delivery, displayed an elevated propensity for apoptosis and senescence compared to intact ACL in C57BL/6 mice. Together, our findings underscore the pivotal role of periostin in ACL health, injury, and potential for healing. [ABSTRACT FROM AUTHOR]

Metal-free, photoredox-catalyzed aromatization-driven deconstructive functionalization of spiro-dihydroquinazolinones with α-CF3 alkenes is presented. The readily available spiro-dihydroquinazolinones reacted efficiently with α-CF3 alkenes during photocatalysis to give the gem-difluoroallylated and the CF3-containing quinazolin-4(3H)-ones in good yields with excellent chemoselectivity. The selectivity depends on the electron effect of substituents in α-CF3 alkenes. A wide range of four-, five-, six-, seven-, eight- and twelve-membered spiro-dihydroquinazolinones were compatible with this transformation. The protocol is also characterized by the mild and redox-neutral reaction conditions, good functional group compatibility and excellent atom economy. Mechanistic studies revealed that the reaction proceeds via a radical pathway. [ABSTRACT FROM AUTHOR]

Calcineurin, protein phosphatase 2B (PP2B) or protein phosphatase 3 (PP3), is a calcium‐dependent serine/threonine protein phosphatase. Calcineurin is widely expressed in the kidney and regulates renal Na+ and K+ transport. In the thick ascending limb, calcineurin plays a role in inhibiting NKCC2 function by promoting the dephosphorylation of the cotransporter and an intracellular sorting receptor, called sorting‐related‐receptor‐with‐A‐type repeats (SORLA), is involved in modulating the effect of calcineurin on NKCC2. Calcineurin also participates in regulating thiazide‐sensitive NaCl‐cotransporter (NCC) in the distal convoluted tubule. The mechanisms by which calcineurin regulates NCC include directly dephosphorylation of NCC, regulating Kelch‐like‐3/CUL3 E3 ubiquitin–ligase complex, which is responsible for WNK (with‐no‐lysin‐kinases) ubiquitination, and inhibiting Kir4.1/Kir5.1, which determines NCC expression/activity. Finally, calcineurin is also involved in regulating ROMK (Kir1.1) channels in the cortical collecting duct and Cyp11 2 expression in adrenal zona glomerulosa. In summary, calcineurin is involved in the regulation of NKCC2, NCC, and inwardly rectifying K+ channels in the kidney, and it also plays a role in modulating aldosterone synthesis in adrenal gland, which regulates epithelial‐Na+‐channel expression/activity. Thus, application of calcineurin inhibitors (CNIs) is expected to abrupt calcineurin‐mediated regulation of transepithelial Na+ and K+ transport in the kidney. Consequently, CNIs cause hypertension, compromise renal K+ excretion, and induce hyperkalemia. [ABSTRACT FROM AUTHOR]