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The effective transition metal‐free photoredox/bismuth dual catalytic reductive dialkylation of nitroarenes with benzaldehydes has been reported. The nitroarene reduction through visible light‐driven photoredox catalysis was integrated with subsequent reductive dialkylation of anilines under bismuth catalysis to enable the cascade reductive alkylation of nitroarenes with carbonyls. Salient features of this relay catalysis system include mild reaction conditions, no requirement for transition metal catalysts, easy handling, step‐economy, and high selectivity. [ABSTRACT FROM AUTHOR]

In recent years, there has been significant focus on China's new drug lag, but relevant research is limited. This study explores the reasons for drug lag by assessing the impact of reforms in China's drug review system, particularly focusing on the influence of clinical development strategies. This study selected drugs first launched in the United States between 2017 and 2022, examining absolute and relative lag between China and the first‐launch country (including submission and review lag). These delays with drugs approved in the European Union and Japan during the same period were compared with uncover the roots of delays in China, further identifying potential factors that could reduce these delays. The results indicate that the National Medical Products Administration (NMPA) has a longer relative lag compared with the European Medicines Agency (EMA) and the Pharmaceuticals and Medical Devices Agency (PMDA). The submission lag time of the NMPA significantly surpasses that of the EMA and PMDA, whereas the review lag time of the NMPA exceeds that of the PMDA but falls short of the EMA. Focusing on clinical trial strategies, bridging trials and multiregional clinical trials (MRCTs) are typically required by the NMPA in East Asia, resulting in longer clinical delay time. Whereas the EMA and PMDA primarily require international MRCTs in Europe and America, with a clinical delay of < 5 months. It is evident that there is a significant gap in clinical trial durations between China and other countries. Further optimization of clinical trial management is necessary to address the lag for new drugs in China. [ABSTRACT FROM AUTHOR]

Cyclohexane epoxide, which contains highly active epoxy groups, plays a crucial role as an intermediate in the preparation of fine chemicals. However, controlling the epoxidation pathway of cyclohexene is challenging due to issues such as the allylic oxidation of cyclohexene and the ring opening of cyclohexane epoxide during the cyclohexene epoxidation process to form cyclohexane oxide. This review focuses on the structure‐activity relationships and synthesis processes of various heterogeneous transition metal‐based catalysts used in cyclohexene epoxidation reactions, including molybdenum(Mo)‐based, tungsten(W)‐based, vanadium(V)‐based, titanium(Ti)‐based, cobalt(Co)‐based, and other catalysts. Initially, the mechanism of cyclohexene epoxidation by transition metal‐based catalysts is examined from the perspective of catalytic active centers. Subsequently, the current research of cyclohexene epoxidation catalysts is summarized based on the perspective of catalyst support. Additionally, the differences between alkyl hydroperoxide, hydrogen peroxide (H2O2), and oxygen (O2) as oxidants are analyzed. Finally, the main factors influencing catalytic performance are summarized, and reasonable suggestions for catalyst design are proposed. This work provides scientific support for the advancement of the olefin epoxidation industry. [ABSTRACT FROM AUTHOR]

In the current study, bi‐metal oxide hybrid nanocomposites prepared by cerium oxide (CeO2) nanoparticles are included into chitosan‐ZnO composites for developing the potential materials of dressing the wound. The wound healing effect of prepared hybrid nanocomposites was evaluated regarding the surface morphology, functional groups, thermal degradation and composite size. The antimicrobial activity of chitosan‐ZnO/CeO2 hybrid nano composites was tested against the pathogens of Staphylococcus aureus and Escherichia coli. The hybrid nanocomposites containing CeO2‐based chitosan and ZnO nanoparticles were taken for optimum dressing included in the vivo studies on the excisional wounds in wistar rats. After 2 weeks, it is seen that the wound treated with CS‐ZnO/CeO2 hybrid nano composites consists of the significant dressing of nearly 100% compared with control which showed nearly 65% of wound closure. Finally, our reported results gave the proof in supporting the availability of CS‐ZnO/CeO2 hybrid nanocomposites contains the dressing of the wounds for the treatment. [ABSTRACT FROM AUTHOR]

Occlusion has been proposed to play a role for body posture and balance, both of which are mediated mainly by the cerebellum. The dorsomedial part of the principal sensory trigeminal nucleus (Vpdm) has direct projection to the cerebellum. The experimental unilateral anterior crossbite (UAC) has an impact on the motor nuclei in the brain stem via trigeminal mesencephalic nucleus (Vme). The current aim was to explore whether UAC has an impact on Vpdm‐cerebellum circuit. The inferior alveolar nerve was injected into cholera toxin B subunit (CTb), the cerebellum was injected into fluoro‐gold (FG), and the Vpdm was injected into biotinylated dextran amine (BDA) to identify the activation of Vpdm‐cerebellum circuit by UAC. Data indicated that there were more neuronal nuclei (NeuN)/CTb/FG triple‐labelled neurons and NeuN/CTb/vesicular glutamate transporter 1(VGLUT1) triple‐labelled neurons in the Vpdm, and more NeuN/BDA/ VGLUT1 triple‐labelled neurons in the cerebellum of rats with UAC than in control rats. The VGLUT1 expression in the Vpdm and cerebellum in the UAC group was higher than that in control rats. These findings indicate an excitatory impact of UAC on the Vpdm‐cerebellum pathway and support the role of occlusion for body posture and balance. [ABSTRACT FROM AUTHOR]

Neurons in the trigeminal mesencephalic nucleus (Vme) have an axon that branches peripherally to innervate the orofacial region and projects centrally to the trigeminal motor nucleus (Vmo). They function as the primary neurons conveying proprioceptive messages. The present study aimed to demonstrate the presence of a periodontal-Vme-Vmo circuit and to provide evidence for its involvement in an experimental unilateral anterior crossbite ( UAC) model, which can induce osteoarthritis in the temporomandibular joint. Cholera toxin B subunit ( CTb) was injected into the inferior alveolar nerve of rats to help identify the central axon terminals of Vme neurons in the Vmo. The levels of vesicular glutamate transporter 1 ( VGLUT1) expressed in the periodontal region, Vme, Vmo, and masseter, and the level of acetylcholinesterase ( AChE) expressed in the masseter, were assessed in UAC rats and controls. In CTb-treated rats, many CTb-labeled cell bodies and endings were identified in the Vme and in the Vmo, respectively. In UAC rats, VGLUT1 was expressed at a statistically significantly higher level in the periodontal ligament, Vme, Vmo, and masseter than it was in control rats. The level of AChE protein was 1.97 times higher in UAC rat masseter compared with control rat masseter. These findings reveal a trigeminal mechanism underlying masseter hyperactivity induced by an altered occlusion. [ABSTRACT FROM AUTHOR]

In the human living environment, heavy metals and chlorpyrifos can have harmful consequences due to their complex combination. In this study, binary, ternary, and quaternary combinations of three heavy metals and chlorpyrifos in different concentrations were evaluated for their combined toxic effects using an electrochemical method, and the MTT method was used to contrast the outcomes. The combined toxic effectiveness assessed by the electrochemical CI method revealed that, except for the binary combination of cadmium chloride and chlorpyrifos, which exhibited an antagonistic effect when mixed at an equal molar ratio, lead nitrate and chlorpyrifos showed an additive effect when combined, the quaternary combination exhibited a complex transition from synergistic to additive to antagonistic effects, the other mixtures showed consistent synergistic effects. When the ratio of heavy metals in the mixture was reduced, all of them displayed synergistic effects, except for the binary mixture of cadmium chloride and chlorpyrifos, which consistently maintained an antagonistic effect, and the ternary mixture of cadmium chloride, lead nitrate, and chlorpyrifos displayed additive effects. The complex toxicity mechanisms of the mixtures do not impact the response of cellular electrochemical signals coming from the intracellular purine bases on cytotoxicity. The electrochemical approach successfully captured the various combined toxic effects of the mixture, and the outcomes were consistent with the MTT method. This method is expected to emerge as a novel approach for detecting combined toxicity. [ABSTRACT FROM AUTHOR]