application-en-bloc-concept-combined-with-anatomic-resection

Application of the En Bloc Concept Combined with Anatomic Resection in Laparoscopic Hepatectomy

Laparoscopic hepatectomy has been reported in many studies, and it is the mainstream method of liver resection. In some particular cases, such as when ...

the second affiliated hospital of Guangzhou medical university

Secondary degeneration in areas beyond ischemic foci can inhibit poststroke recovery. The cysteine protease Cathepsin B (CathB) regulates cell death and intracellular protein catabolism. To investigate the roles of CathB in the development of secondary degeneration in the ventroposterior nucleus (VPN) of the ipsilateral thalamus after focal cerebral infarction, infarct volumes, immunohistochemistry and immunofluorescence, and Western blotting analyses were conducted in a distal middle cerebral artery occlusion (dMCAO) stroke model in adult rats. We observed marked neuron loss and gliosis in the ipsilateral thalamus after dMCAO, and the expression of CathB and cleaved caspase-3 in the VPN was significantly upregulated; glial cells were the major source of CathB. Although it had no effect on infarct volume, delayed intracerebroventricular treatment with the membrane-permeable CathB inhibitor CA-074Me suppressed the expression of CathB and cleaved caspase-3 in ipsilateral VPN and accordingly alleviated the secondary degeneration. These data indicate that CathB mediates a novel mechanism of secondary degeneration in the VPN of the ipsilateral thalamus after focal cortical infarction and suggest that CathB might be a therapeutic target for the prevention of secondary degeneration in patients after stroke.

Inhibition of Cathepsin B Alleviates Secondary Degeneration in Ipsilateral Thalamus After Focal Cerebral Infarction in Adult Rats.

Epigenetic modification contributes to the pathogenesis of cerebral ischemia. Piwil2 belongs to the PIWI proteins subfamily and has a key role in the regulation of gene transcription through epigenetics. However, the roles of Piwil2 in cerebral ischemia have not been investigated. In this study, we aim to elucidate the roles and the underlying molecular mechanisms of Piwil2 in ischemic tolerance induced by hypoxic postconditioning (HPC) against transient global cerebral ischemia (tGCI). We found that the expression of Piwil2 in CA1 was downregulated by HPC after tGCI. Silencing Piwil2 with antisense oligodeoxynucleotide (AS-ODN) in CA1 after tGCI decreased the expression of apoptosis-related proteins and exerted neuroprotective effects. Opposite results were observed after overexpression of Piwil2 induced by administration of Piwil2-carried lentivirus. Furthermore, we revealed differentially expressed Piwil2-interacting piRNAs in CA1 between HPC and tGCI groups by RNA binding protein immunoprecipitation (RIP) assay. Moreover, downregulating Piwil2 induced by HPC or AS-ODN after tGCI caused a marked reduction of DNA methyltransferase 3A (DNMT3A), which in turn abolished the tGCI-induced increase in the DNA methylation of cyclic AMP response element-binding 2 (CREB2), thus increasing mRNA and protein of CREB2. Finally, downregulating Piwil2 restored dendritic complexity and length, prevented the loss of dentritic spines, thereby improving cognitive function after tGCI. These data firstly reveal that Piwil2 plays an important part in HPC-mediated neuroprotection against cerebral ischemia through epigenetic regulation of CREB2.

Article	Year
Inhibition of Cathepsin B Alleviates Secondary Degeneration in Ipsilateral Thalamus After Focal Cerebral Infarction in Adult Rats. Journal of neuropathology and experimental neurology\| PubMed ID: 27371711	2016
Attenuation of Piwil2 induced by hypoxic postconditioning prevents cerebral ischemic injury by inhibiting CREB2 promoter methylation. Brain pathology (Zurich, Switzerland)\| PubMed ID: 35794855	2023

Xinyu Li

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