A novel twin-grasper assisted mucosal inverted closure technique for closing large artificial gastric mucosal defects.

BACKGROUND: Large artificial gastric mucosal defects are always left unclosed for natural healing due to technique difficulties in closure. This study aims to evaluate the feasibility and safety of a new Twin-grasper Assisted Mucosal Inverted Closure (TAMIC) technique in closing large artificial gastric mucosal defects. METHODS: Endoscopic submucosal dissection (ESD) was performed in fifteen pigs to create large gastric mucosal defects. The mucosal defects were then either left unclosed or closed with metallic clips using TAMIC technique. Successful closure rate and the wound outcomes were assessed. RESULTS: Two mucosal defects with size of about 4.0 cm were left unclosed and healed two months after surgery. Thirteen large gastric mucosal defects were created by ESD with a medium size of 5.9 cm and were successfully closed with the TAMIC technique (100%), even in a mucosal defect with a width up to 8.5 cm. The mean closure time was 59.0 min. Wounds in eight stomachs remained completely closed 1 week after surgery (61.5%), while closure in the other five stomachs had partial wound dehiscence (38.5%). Four weeks later, all the closed defects healed well and 61.5% of the wounds still remained completely closed during healing. There was no delayed perforation or bleeding after surgery. In addition, there was less granulation in the submucosal layer of the closed wound sites than those under natural healing. CONCLUSIONS: The present study suggests that TAMIC is feasible and safe in closing large artificial gastric mucosal defects and could improve mucosal recovery compared to natural healing process.

Target immobilization on glass microfiber membranes as a label-free strategy for hit identification.

The discovery of novel chemical entities targeting G protein-coupled receptors (GPCRs) is usually guided by their receptor affinity. However, traditional affinity assay methods and hit identification procedures are usually laborious and expensive. In this work, the type-2 vasopressin receptor (V2R) was chosen as a prototypical GPCR. Membrane fragments from cells highly expressing SNAP-V2R were immobilized on the surface of a glass microfiber (GMF) coated with O6-benzylguanine (BG). This was achieved by transferring the benzyl group of BG to the active site of the SNAP-tag through a nucleophilic substitution reaction. As a result, a biofilm called SNAP-V2R@GMF-BG was produced that showed good specificity and stability. The adsorption ratio for each V2R ligand treated with SNAP-V2R@GMF-BG was determined by HPLC and exhibited a good linear correlation with the Ki value determined by displacement assays. Furthermore, a Ki prediction assay was performed by comparing the data with that generated by a homogeneous time-resolved fluorescence (HTRF) assay. SNAP-V2R@GMF-BG was also used to screen hit compounds from natural products. After SNAP-V2R@GMF-BG was incubated with the total extract, the ligand that binds to V2R could be separated and subjected to LC‒MS analysis for identification. Baicalein was screened from Clerodendranthus spicatus and verified as a potential V2R antagonist. This V2R-immobilized GMF platform can help determine the affinity of V2R-binding hit compounds and screen the compounds efficiently and accurately.

Electroacupuncture Increases the Expression of Gas7 and NGF in the Prefrontal Cortex of Male Rats with Focal Cerebral Ischemia.

OBJECTIVE: To investigate the potential mechanisms underlying the migration of endogenous neural stem cells (eNSCs) to the frontal cortex to differentiate into neurons, and to monitor the effect of electroacupuncture (EA) regulation of focal cerebral ischemia (FCI) in rats on the expression of growth arrest-specific protein 7 (Gas7) and nerve growth factor (NGF) in the prefrontal cortex (PFC). METHODS: Randomly, forty-eight male Sprague-Dawley rats were divided into four groups: Normal, Sham operation, Model, and EA. The right middle cerebral artery was embolized utilizing the thread-embolism technique. In the EA group, "Baihui" and "Zusanli" points were treated with electroacupuncture for 30 minutes, once a day, for 21 days. Nissl staining revealed the neuronal morphology of the PFC. Using immunohistochemistry and Western blot, the expression of Gas7 and NGF in the right PFC was observed. RESULTS: Nissl staining showed clear PFC neurons with centered nuclei and distinct nucleoli in the Normal and Sham groups. In the Model group, the PFC nuclei were distinctively smaller. The neuronal morphology in the EA group resembled that of the Normal group. Results from Western blot and immunohistochemistry were comparable. The expression of Gas7 and NGF in the Sham surgery group did not differ significantly from the Normal group. However, the expression of Gas7 and NGF in the Model group was significantly lower than in the Normal group. The expression of Gas7 and NGF was significantly higher in the EA group than in the Model group. CONCLUSIONS: EA can increase the expressions of Gas7 and NGF in the ischemic prefrontal cortex, which may be one of the mechanisms by which EA promotes the differentiation of eNSCs into neurons in the injured area.

Twin-grasper assisted mucosal inverted closure achieves complete healing of large perforations after gastric endoscopic full-thickness resection.

OBJECTIVES: This study aimed to demonstrate the feasibility and safety of a novel twin-grasper assisted mucosal inverted closure (TAMIC) technique for large perforations after gastric endoscopic full-thickness resection (EFTR) in a porcine model. METHODS: Iatrogenic large perforations of the stomach were created and closed by an experienced endoscopist using the TAMIC technique in 12 pigs. Repeat gastroscopy was performed in 4 weeks after surgery to examine the wound sites and then the animals were killed. The primary outcomes were the successful TAMIC closure rate and the complete healing rate. Secondary end points included procedure time of TAMIC, complete inverted healing rate, delayed bleeding rate, and postsurgery perforation. Histologies of the wounds were analyzed by hematoxylin-eosin, Masson trichrome, and immunohistochemistry staining. RESULTS: The median size of the defects was 3.5 (range 2.5-4.5) cm. TAMIC was successfully performed in all the 12 pigs. Complete healing was achieved in 11 pigs 4 weeks after operation as one pig died postsurgery due to severe pneumonia. The median procedure time for TAMIC was 39 (range 23-81) min. The complete inverted healing rate was 45.5% (5/11). No delayed bleeding or postsurgery perforation was observed. Histologic analyses showed that both the epithelium and muscularis mucosae layers were appropriately connected under inverted healing. CONCLUSIONS: Twin-grasper assisted mucosal inverted closure is feasible and safe for closure of large perforations after gastric EFTR and could be a propagable and promising technique for clinical practice.

Target Screen of Anti-Hyperuricemia Compounds from Cortex Fraxini In Vivo Based on ABCG2 and Bioaffinity Ultrafiltration Mass Spectrometry.

The ATP-binding cassette (ABC) transporter ABCG2 is a significant urate transporter with a high capacity, and it plays a crucial role in the development of hyperuricemia and gout. Therefore, it has the potential to be targeted for therapeutic interventions. Cortex Fraxini, a traditional Chinese medicine (TCM), has been found to possess anti-hyperuricemia properties. However, the specific constituents of Cortex Fraxini responsible for this effect are still unknown, particularly the compound that is responsible for reducing uric acid levels in vivo. In this study, we propose a target screening protocol utilizing bio-affinity ultrafiltration mass spectrometry (BA-UF-MS) to expediently ascertain ABCG2 ligands from the plasma of rats administered with Cortex Fraxini. Our screening protocol successfully identified fraxin as a potential ligand that interacts with ABCG2 when it functions as the target protein. Subsequent investigations substantiated fraxin as an activated ligand of ABCG2. These findings imply that fraxin exhibits promise as a drug candidate for the treatment of hyperuricemia. Furthermore, the utilization of BA-UF-MS demonstrates its efficacy as a valuable methodology for identifying hit compounds that exhibit binding affinity towards ABCG2 within TCMs.

Effect of Celastrus orbiculatus in inhibiting Helicobacter pylori induced inflammatory response by regulating epithelial mesenchymal transition and targeting miR-21/PDCD4 signaling pathway in gastric epithelial cells.

BACKGROUND: The extract of Celastrus orbiculatus (COE) have been studied for anti-Helicobacter pylori (H. pylori) activity and anti-cancer effects in vitro and in vivo. However, the molecular mechanism by which COE inhibits H. pylori-induced inflammatory response has not been fully elucidated so far. METHODS: The effects of COE on viability, morphological changes, inflammatory cytokine secretion, protein and mRNA expression were analyzed by MTT assay, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, western blot and real-time PCR (RT-PCR), respectively. The methylation level of programmed cell death 4 (PDCD4) promoter was investigated by methylation-specific PCR. (MSP) . RESULTS: COE effectively inhibited the H.pylori-induced inflammatory response by regulating epithelial-mesenchymal transition (EMT). The methylation level of PDCD4 promoter was suppressed by COE, which increased the expression ofPDCD4. Moreover, COE could inhibit microRNA-21 (miR-21) expression, as shown by an enhancement of its target gene PDCD4. Furthermore, both miR-21 over-expression and PDCD4 silencing attenuated the anti-inflammatory effect. of COE. CONCLUSIONS: COE inhibits H. pylori induced inflammatory response through regulating EMT, correlating with inhibition of miR-21/PDCD4 signal pathways in gastric epithelial cells.

Mixed reality navigation training system for liver surgery based on a high-definition human cross-sectional anatomy data set.

OBJECTIVES: This study aims to use the three-dimensional (3D) mixed-reality model of liver, entailing complex intrahepatic systems and to deeply study the anatomical structures and to promote the training, diagnosis and treatment of liver diseases. METHODS: Vascular perfusion human specimens were used for thin-layer frozen milling to obtain liver cross-sections. The 104-megapixel-high-definition cross sectional data set was established and registered to achieve structure identification and manual segmentation. The digital model was reconstructed and data was used to print a 3D hepatic model. The model was combined with HoloLens mixed reality technology to reflect the complex relationships of intrahepatic systems. We simulated 3D patient specific anatomy for identification and preoperative planning, conducted a questionnaire survey, and evaluated the results. RESULTS: The 3D digital model and 1:1 transparent and colored model of liver established truly reflected intrahepatic vessels and their complex relationships. The reconstructed model imported into HoloLens could be accurately matched with the 3D model. Only 7.7% participants could identify accessory hepatic veins. The depth and spatial-relationship of intrahepatic structures were better understandable for 92%. The 100%, 84.6%, 69% and 84% believed the 3D models were useful in planning, safer surgical paths, reducing intraoperative complications and training of young surgeons respectively. CONCLUSIONS: A detailed 3D model can be reconstructed using the higher quality cross-sectional anatomical data set. When combined with 3D printing and HoloLens technology, a novel hybrid-reality navigation-training system for liver surgery is created. Mixed Reality training is a worthy alternative to provide 3D information to clinicians and its possible application in surgery. This conclusion was obtained based on a questionnaire and evaluation. Surgeons with extensive experience in surgical operations perceived in the questionnaire that this technology might be useful in liver surgery, would help in precise preoperative planning, accurate intraoperative identification, and reduction of hepatic injury.

Electroacupuncture Inhibits Myelin Sheath Injury in the Internal Capsule After Focal Cerebral Infarction in Rats Through the Nogo-A/NgR Signaling Pathway.

BACKGROUND Ischemic stroke is usually accompanied by white matter damage. The effect of electroacupuncture (EA) on ameliorating white matter damage is still unclear. The purpose of this study was to explore the precise mechanism of EA in treating ischemic white matter. MATERIAL AND METHODS In this study, 40 Sprague-Dawley rats were randomly divided into 4 groups: normal group, the sham-operated group, model group, and EA group. The stroke model was established by right middle cerebral artery occlusion, and EA was performed 24 h after the operation for 30 min per day. After 14 days of treatment, brain tissue samples were collected. Hematoxylin and eosin and Luxol fast blue staining were used to observe the changes of white matter damage in the internal capsule (IC). The expression levels of myelin basic protein (MBP), Nogo-A, and Nogo-A receptor (NgR) were detected by immunohistochemistry and western blot. RESULTS Compared with the sham-operated group, the model group had decreased expression of MBP and significantly increased expression of Nogo-A and NgR (P<0.05). Compared with the model group, the IC damage was alleviated in the EA group. Immunohistochemistry and western blot analysis showed that EA significantly increased the expression of MBP in white matter (P<0.05) and downregulated the expression levels of Nogo-A and NgR (P<0.05). CONCLUSIONS The results of this study indicate that EA can inhibit the expression of Nogo-A/NgR and promote myelin sheath regeneration.

[Effects of electroacupuncture on myelin-related protein in corpus callosum of rats with focal cerebral ischemia].

OBJECTIVE: To observe the effect of electroacupuncture(EA)on the expression of myelin basic protein (MBP), axon growth inhibitor Nogo-A and Nogo receptor (NgR) in corpus callosum of rats with focal cerebral ischemia, so as to explore the mechanism of EA underlying improving ischemic white matter injury. METHODS: Fourty male SD rats were randomly divided into normal, sham operation, model and EA groups, with 10 rats in each group. The focal cerebral ischemia rat model was established by occlusion of the middle cerebral artery (MCAO). EA was applied to "Baihui"(GV20) and "Zusanli"(ST36) on the left side for 30 min, once daily for 14 days. Neurological function score and the adhensive removal test were used to evaluate neurological deficit severity; Hematoxylin-esion staining was used to observe the pathological changes in myelin of corpus callosum and luxol fast blue（LFB） staining was used to observe the myelin of corpus callosum. Immunohistochemical staining and Western blot were used to detect the expressions of MBP、Nogo-A and NgR in the ischemic corpus callosum. RESULTS: After MCAO, the neurological function score was significantly increased (P<0.05), the time required for contact with tape and tape removal was longer (P<0.001), the intensity of LFB staining and the expression of MBP decreased, while the veside area and the expression of Nogo-A and its receptor NgR increased (P<0.01, P<0.05) in the model group relevant to the normal and sham operation groups. The fiber arrangement of the corpus callosum on the ischemic side was disordered and a large amount of myelin sheath was lost in the model group. Following the treatment, the neurological deficit score of EA group was gradually decreased and significantly decreased on the 3rd, 7th and 14th day (P<0.05), and the time to remove the adhesive tape was shortened at the 7th and 14th day (P<0.001). The shape of the corpus callosum in the EA group was close to normal, and the myelin structure was relatively complete. The intensity of LFB staining and the expression of MBP was increased (P<0.05, P<0.01) while the expression of Nogo-A and its receptor NgR were decreased in the EA group relevant to the model group (P<0.01). CONCLUSION: EA can play a protective role in myelin of the corpus callosum after cerebral ischemia, which may be related to down-regulating the expressions of Nogo-A and NgR.

Upcycling of Fe-bearing sludge: preparation of erdite-bearing particles for treating pharmaceutical manufacture wastewater.

Groundwater treatment sludge is a type of solid waste with 9.0-28.9% wt.% Fe content and is precipitated in large quantity from backwash wastewater in groundwater treatment. The sludge is mainly composed of fine particles containing Fe, Si and Al oxides, such as ferrihydrite, quartz and boehmite. The Fe oxides mostly originate from the oxidation of ferrous Fe in groundwater, whilst the silicate/aluminium compounds mainly originate from the broken quartz sand filter in the backwash step. In general, the sludge is firstly coagulated, dewatered by filter pressing and finally undergoes harmless solidification before it is sent to landfills. However, this process is costly (approximately US$66.1/t) and complicated. In this study, groundwater treatment sludge was effectively recycled to prepare novel erdite-bearing particles via a one-step hydrothermal method by adding only Na2S·9H2O. After hydrothermal treatment, the quartz and boehmite of the sludge were dissolved and recrystallised to sodalite, whilst ferrihydrite was converted to an erdite nanorod at 160 °C and a hematite at 240 °C. SP160 was prepared as fine nanorod particles with 200 nm diameter and 2-5 µm length at a hydrothermal temperature of 160 °C. Nearly 100% OTC and its derivatives in pharmaceutical manufacture wastewater were removed by adding 0.1 g SP160. The major mechanism for the removal was the spontaneous hydrolysis of erdite in SP160 to generate Fe oxyhydroxide and use many hydroxyl groups for coordinating OTC and its derivatives. This study presents a novel method for the resource reutilisation of waste groundwater treatment sludge and reports efficient erdite-bearing particles for pharmaceutical manufacture wastewater treatment.

Upcycling of groundwater treatment sludge to magnetic Fe/Mn-bearing nanorod for chromate adsorption from wastewater treatment.

Groundwater treatment sludge is a Fe/Mn-bearing waste that is mass produced in groundwater treatment plant. In this study, sludge was converted to a magnetic adsorbent (MA) by adding ascorbate. The sludge was weakly magnetised in the amorphous form with Fe and Mn contents of 28.8% and 8.1%, respectively. After hydrothermal treatment, Fe/Mn oxides in the sludge was recrystallised to siderite and rhodochrosite, with jacobsite as the intermediate in the presence of ascorbate. With an increment in ascorbate dosage, the obtained magnetic adsorbent had a significant increase in chromate adsorption but a decrease in magnetisation. When the Mascorbate/MFe molar ratio was 10, the produced MA-10 was a dumbbell-shaped nanorod with a length of 2-5 µm and a diameter of 0.5-1 µm. This MA-10 showed 183.2 mg/g of chromate adsorption capacity and 2.81 emu/g of magnetisation. The mechanism of chromate adsorption was surface coprecipitation of the generated Cr3+ and Fe3+/Mn4+ from redox reaction between chromate and siderite/rhodochrosite on MA-10, separately. This study demonstrated an efficient recycling route of waste sludge from groundwater treatment to produce MA for treating chromate-bearing wastewater.