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Perioperative neurocognitive disorders (PNDs) are now considered the most common neurological complication in older adult patients undergoing surgical procedures. A significant increase exists in the incidence of post-operative disability and mortality in patients with PNDs. However, no specific treatment is still available for PNDs. Recent studies have shown that exercise may improve cognitive dysfunction-related disorders, including PNDs. Neuroinflammation is a key mechanism underlying exercise-induced neuroprotection in PNDs; others include the regulation of gut microbiota and mitochondrial and synaptic function. Maintaining optimal skeletal muscle mass through preoperative exercise is important to prevent the occurrence of PNDs. This review summarizes current clinical and preclinical evidence and proposes potential molecular mechanisms by which perioperative exercise improves PNDs, providing a new direction for exploring exercise-mediated neuroprotective effects on PNDs. In addition, it intends to provide new strategies for the prevention and treatment of PNDs. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of low‐concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal‐C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3O4 hollow nanoparticles on ordered macroporous N‐doped carbon framework (Vo−HCo3O4/OMNC) towards photoreduction of low‐concentration CO2. In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co−O−Co sites. The formation of asymmetric active site switches the CO2 configuration from a single‐site linear model to a multiple‐sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo−HCo3O4/OMNC shows unprecedent activity in the photocatalytic conversion of low‐concentration CO2 (10 % CO2/Ar) under laboratory light source or even natural sunlight, affording a syngas yield of 337.8 or 95.2 mmol g−1 h−1, respectively, with an apparent quantum yield up to 4.2 %. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of low‐concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal‐C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3O4 hollow nanoparticles on ordered macroporous N‐doped carbon framework (Vo−HCo3O4/OMNC) towards photoreduction of low‐concentration CO2. In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co−O−Co sites. The formation of asymmetric active site switches the CO2 configuration from a single‐site linear model to a multiple‐sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo−HCo3O4/OMNC shows unprecedent activity in the photocatalytic conversion of low‐concentration CO2 (10 % CO2/Ar) under laboratory light source or even natural sunlight, affording a syngas yield of 337.8 or 95.2 mmol g−1 h−1, respectively, with an apparent quantum yield up to 4.2 %. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of low‐concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal‐C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3O4 hollow nanoparticles on ordered macroporous N‐doped carbon framework (Vo−HCo3O4/OMNC) towards photoreduction of low‐concentration CO2. In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co−O−Co sites. The formation of asymmetric active site switches the CO2 configuration from a single‐site linear model to a multiple‐sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo−HCo3O4/OMNC shows unprecedent activity in the photocatalytic conversion of low‐concentration CO2 (10 % CO2/Ar) under laboratory light source or even natural sunlight, affording a syngas yield of 337.8 or 95.2 mmol g−1 h−1, respectively, with an apparent quantum yield up to 4.2 %. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of low‐concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal‐C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3O4 hollow nanoparticles on ordered macroporous N‐doped carbon framework (Vo−HCo3O4/OMNC) towards photoreduction of low‐concentration CO2. In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co−O−Co sites. The formation of asymmetric active site switches the CO2 configuration from a single‐site linear model to a multiple‐sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo−HCo3O4/OMNC shows unprecedent activity in the photocatalytic conversion of low‐concentration CO2 (10 % CO2/Ar) under laboratory light source or even natural sunlight, affording a syngas yield of 337.8 or 95.2 mmol g−1 h−1, respectively, with an apparent quantum yield up to 4.2 %. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO2 into syngas is a promising way to address the energy and environmental challenges. Here we report the integration of Ni−Co dual sites on Ni doped Co3O4 ultrathin nanosheets assembled double‐hollow nanotube (Ni−Co3O4 NSDHN) for efficient photoreduction of low‐concentration CO2. Quasi in situ spectra and density functional theory calculations demonstrate that the declining of d‐band center of Ni−Co dual sites enables the electrons accumulation in the dxz/dyz‐2π* and dz2‐5σ orbitals. As a result, the binding strength of *CO is weakened and the *H adsorption site is modulated from metal sites to an oxygen site. Remarkably, Ni−Co3O4 NSDHN exhibits superior diluted CO2 photoconversion activity and controllable selectivity under the irradiation of visible light or even natural sunlight. A syngas evolution rate of 170.0 mmol g−1 h−1 with an apparent quantum yield of 3.7 % and continuously adjustable CO/H2 ratios from 1 : 10 to 10 : 1 are achieved. [ABSTRACT FROM AUTHOR]

Background: The α7 nicotinic acetylcholine receptor (α7nAChR) is a promising therapeutic target in neurodegenerative diseases. This study examined the effects of surgery and anesthesia on α7nAChR expression in the central nervous system and determined the mechanisms by which α7nAChR mediates neuroprotection in perioperative neurocognitive disorders (PNDs) in aged mice. Methods: Eighteen-month-old male C57BL/6J mice underwent aseptic laparotomy under isoflurane anesthesia, maintaining spontaneous ventilation to establish the PNDs model. Agonists and antagonists of the α7nAChR and tropomyosin receptor kinase B (TrkB) receptors were administered before anesthesia. The α7nAChR expression, peripheral as well as hippocampal interleukin-1β (IL-1β), and the brain-derived neurotrophic factor (BDNF) levels were assessed. Separate cohorts of aged mice were tested for cognitive decline using the Morris water maze (MWM). Results: Surgery and anesthesia significantly suppressed α7nAChR expression in the hippocampus and cortex. Surgery-induced IL-1β upregulation in the serum as well as hippocampus and hippocampal microglial activation were reversed by the α7nAChR agonist. A significant reduction in the hippocampal BDNF levels were also observed. The α7nAChR stimulation reversed, and α7nAChR suppression promoted BDNF reduction in the hippocampus. Blocking the BDNF/TrkB signaling pathway abolished α7nAChR-induced neuroprotection in PNDs, as evidenced by poor cognitive performance in the MWM test. Conclusions: These data reveal that α7nAChR plays a key role in PNDs. The mechanisms of the anti-inflammatory pathway and BDNF/TrkB signaling pathways are involved in α7nAChR-meidiated neuroprotection in PNDs. [ABSTRACT FROM AUTHOR]