PHLDA2 overexpression facilitates senescence and apoptosis via the mitochondrial route in human nucleus pulposus cells by regulating Wnt/ß-catenin signalling pathway.

Low back pain is a common clinical symptom of intervertebral disc degeneration (IVDD), which seriously affects the quality of life of the patients. The abnormal apoptosis and senescence of nucleus pulposus cells (NPCs) play important roles in the pathogenesis of IVDD. PHLDA2 is an imprinted gene related to cell apoptosis and tumour progression. However, its role in NPC degeneration is not yet clear. Therefore, this study was set to explore the effects of PHLDA2 on NPC senescence and apoptosis and the underlying mechanisms. The expression of PHLDA2 was examined in human nucleus pulposus (NP) tissues and NPCs. Immunohistochemical staining, magnetic resonance imaging imaging and western blot were performed to evaluate the phenotypes of intervertebral discs. Senescence and apoptosis of NPCs were assessed by SA-ß-galactosidase, flow cytometry and western blot. Mitochondrial function was investigated by JC-1 staining and transmission electron microscopy. It was found that the expression level of PHLDA2 was abnormally elevated in degenerated human NP tissues and NPCs. Furthermore, knockdown of PHLDA2 can significantly inhibit senescence and apoptosis of NPCs, whereas overexpression of PHLDA2 can reverse senescence and apoptosis of NPCs in vitro. In vivo experiment further confirmed that PHLDA2 knockdown could alleviate IVDD in rats. Knockdown of PHLDA2 could also reverse senescence and apoptosis in IL-1ß-treated NPCs. JC-1 staining indicated PHLDA2's knockdown impaired disruption of the mitochondrial membrane potential and also ameliorated superstructural destruction of NPCs as showed by transmission electron microscopy. Finally, we found the PHLDA2 knockdown promoted Collagen-II expression and suppressed MMP3 expression in NPCs by repressing wnt/ß-catenin pathway. In conclusion, the results of the present study showed that PHLDA2 promotes IL-1ß-induced apoptosis and senescence of NP cells via mitochondrial route by activating the Wnt/ß-catenin pathway, and suggested that therapy targeting PHLDA2 may provide valuable insights into possible IVDD therapies.

[Hydrochemical Characteristics and Genesis Mechanism of Groundwater in the Dry Period in the Zhangjiakou Area].

In order to better support the construction of the capital water conservation functional area and ecological environment support area， research on the chemical characteristics of groundwater and its formation mechanism in the dry period in the Zhangjiakou area can provide a great reference for the rational development and utilization of groundwater resources. A total of 41 groups of groundwater samples were collected， and the hydrochemical types， composition characteristics， and control factors of groundwater in the study area were analyzed by using the combined method of descriptive statistical analysis， Piper triplot， correlation analysis， Gibbs plot， and ion ratio. The results showed that the groundwater in the study area was weakly alkaline， with the total hardness and ρ（TDS） ranging from 105.00 mg·L-1 to 1 433.00 mg·L-1 and 137.00 mg·L-1 to 2 286.00 mg·L-1， respectively. The total hardness and TDS mass concentrations of groundwater in the Bashang area were higher than those in the Baxia area. HCO3- and Na+ were the main dominant anions and cations in the groundwater in the study area. The highest overstandard rate of the main components in groundwater was that of total hardness （36.59%）. The overstandard rate and maximum excess multiple of each component in groundwater in the Bashang area were greater than those in the Baxia area. HCO3-Ca·Mg·Na was the main type of groundwater hydrochemistry in the study area， and there was little difference between the Bashang area and the Baxia area. SO42-， Cl-， HCO3-， Na+， and Mg2+ contributed the most to TDS. The chemical characteristics of groundwater were affected by weathering and filtration of rock minerals such as salt rock， albite， and dolomite； cation exchange； and human activities. Evaporative crystallization and atmospheric precipitation contributed to a small part of the main ion source of groundwater in the area. The effect of human activities on groundwater in the Bashang area was greater than that in the Baxia area， and NO3- mainly originated from agricultural activities.

Effects of combined natural synergists and chemical inhibitors on yield, nitrogen utilization and balance in wheat/maize rotation system.

Urease inhibitors and nitrification inhibitors can enhance nitrogen (N) fertilizer utilization efficiency and reducing N losses through regulating urea-N transformation. Common urease or nitrification inhibitors, however, are predominantly chemically synthesized and high-cost. Furthermore, their inhibitory effects are mediated by soil pro-perties, climatic conditions, and crop systems. In this study, we conducted a field experiment using natural synergists humic acid/zeolite, along with chemical nitrification inhibitor dicyandiamide (DCD) and their combination to elucidate the impacts of natural synergists combined with chemical inhibitors on annual yield, nitrogen utilization efficiency, soil nitrate-N accumulation, and nitrogen balance within the wheat/maize rotation system. The treatments included no nitrogen fertilizer application (CK), single application of urea (N), urea +DCD (ND), urea + humic acid (NH), urea + zeolite (NP), urea + urease inhibitor N-butylthiophosphoric triamide + DCD (NUD), urea + humic acid + DCD (NHD), and urea + zeolite + DCD (NPD). The results showed that, compared to the treatments NH and NP, the integration of humic acid or zeolite with DCD (NHD and NPD) significantly increased maize yield (11268 and 11397 kg·hm-2) and total annual yield (20494 and 20582 kg·hm-2), which were comparable to those of combined chemical urease and nitrification inhibitors (NUD). The NHD and NPD treatments had higher nitrogen utilization efficiency and lower soil nitrate-N accumulation in 80-100 cm soil layer across all seasons relative to the N treatment, which had no significant difference compared to the NUD treatment. Furthermore, a decline in soil nitrogen surplus by 10.7% and 13.9% was observed when comparing the NHD and NPD treatments with the NH and NP treatments, respectively. These findings suggested that combined humic acid or zeolite and chemical nitrification inhibitors could effectively enhance crop yield and N utilization efficiency and meet the requirements of the green and environmental preservation of modern agriculture.

Thrombectomy alone versus intravenous thrombolysis before thrombectomy for acute basilar artery occlusion.

BACKGROUND: Endovascular treatment (EVT) is a well-established approach for acute ischemic stroke. Whether bridging intravenous thrombolysis (IVT) before EVT confers any benefits remains uncertain. The objective of the study was to compare the efficacy and safety of direct EVT with or without bridging IVT in patients with acute basilar artery occlusion (BAO). METHODS: This multicenter cohort study enrolled 647 patients with acute BAO who underwent either bridging IVT before EVT or direct EVT from the BASILAR registry. The primary outcome was an independent functional outcome measured by the modified Rankin Scale (mRS) score of 0-2. Secondary outcomes included excellent functional outcome (mRS 0-1), favorable functional outcome (mRS 0-3), and mortality rate at 90 days, as well as symptomatic intracranial hemorrhage (sICH), and successful reperfusion between the two treatment groups. RESULTS: Direct EVT and bridging IVT before EVT exhibited similar primary outcomes (27.3% vs 27.7%, respectively) and distributions of mRS scores at 90 days. Moreover, rates of sICH and 90-day mortality were not significantly different between the two groups (7.3% vs 6.0%, adjusted OR (aOR) 0.79, 95% CI 0.34 to 1.86, P=0.84 for sICH; 46.8% vs 43.7%, aOR 0.86, 95% CI 0.54 to 1.38, P=0.53 for mortality). CONCLUSIONS: Among patients with acute BAO, functional outcomes were similar between those treated with bridging IVT before EVT and those treated with direct EVT, and there was no difference between the two groups in terms of sICH and mortality rates.

Effect of humic acid-modified attapulgite on polycyclic aromatic hydrocarbon adsorption and release from paddy soil into the overlying water in a rice-crab coculture paddy ecosystem and the underlying process.

Phenanthrene (Phe), a typical polycyclic aromatic hydrocarbon (PAH) pollutant, poses an enormous safety risk to rice-crab coculture (RC) paddy ecosystems. In this study, humic acid-modified purified attapulgite (HA-ATP) with a composite structure was successfully fabricated to adsorb PAHs released from paddy soil to overlying water in RC paddy ecosystems in Northeast China. The maximum crab bioturbation intensities for dissolved Phe and particulate Phe were 64.83nullng/L·(cm2·d) and 214.29nullng/L·(cm2·d), respectively. The highest concentration of dissolved Phe released from paddy soil to overlying water due to crab bioturbation reached 80.89nullng/L, while the corresponding concentration of particulate Phe reached 267.36nullng/L. The dissolved organic carbon (DOC) and total suspended solid (TSS) concentrations in overlying water increased correspondingly and were strongly correlated with dissolved Phe and particulate Phe concentrations, respectively (P < 0.05). When 6% HA-ATP was added to the surface layer of paddy soil, the efficiency of the adsorption of Phe release was 24.00%-36.38% for particulate Phe and 89.99%-91.91% for dissolved Phe. Because HA-ATP has a large adsorption pore size (11.33 nm) and surface area (82.41nullm2/g) as well as many HA functional groups, it provided multiple hydrophobic adsorption sites for dissolved Phe, which was conducive to competitive adsorption with DOC in the overlying water. In contrast to that adsorbed by DOC, the average proportion of dissolved Phe adsorbed by HA-ATP reached 90.55%, which reduced the dissolved Phe concentration in the overlying water. Furthermore, even though the particulate Phe was resuspended by crab bioturbation, HA-ATP immobilized particulate Phe due to its capacity to inhibit desorption, which achieved the goal of reducing the Phe concentration in the overlying water. This result was confirmed by research on the adsorption-desorption characteristics of HA-ATP. This research provides an environmentally friendly in situ remediation method for reducing agricultural environmental risks and improving rice crop quality.

Relationships between rumen microbes, short-chain fatty acids, and markers of white adipose tissue browning during the cold season in grazing Mongolian sheep (Ovisaries).

Mongolian sheep are characteristically cold-tolerant and they partially depend on seasonal browning of white adipose tissue (WAT) to acclimate to cold environments. The present work aimed to examine the rumen microbes, rumen fermentation profile, and relationships between the rumen microbiota, short-chain fatty acids (SCFAs), and markers of WAT browning and are thus conducive to exploring the plateau environment adaptability of Mongolian sheep in the cold season. A comparative analysis of the rumen microbes and SCFAs in the cold and warm seasons was conducted. Rumen microbes were analyzed using Illumina sequencing of the 16S rRNA gene. Ruminal SCFAs were determined by gas chromatography. Spearman's correlation test was used to determine the relationships between the rumen microbiota, SCFAs, and markers of WAT browning. Microbial 16S rRNA sequencing revealed a marked shift in rumen microbiota composition between the two seasons, and the bacteria were characterized by increased levels of the Actinobacteria and genera Christensenellaceae R-7 group, Ruminococcaceae UCG-011, Rikenellaceae RC9 gut group, Papillibacter, and Butyrivibrio 2 and reduced levels of Prevotella 1 and Ruminococcaceae UCG-014 in the cold season (P<0.05). Furthermore, the concentrations of SCFAs such as acetate and butyrate were significantly increased in the cold season (P<0.001 and P<0.05, respectively). Correlation analysis demonstrated that the relative abundances of the Actinobacteria and the genera Christensenellaceae R-7 group, Butyrivibrio 2, Ruminococcaceae UCG-002, and Ruminococcaceae UCG-011, identified as members of the Christensenellaceae, Lachnospiraceae, and Ruminococcaceae families (all within Firmicutes), were positively correlated with markers of browning in either retroperitoneal WAT or perirenal WAT, and acetate was positively correlated with Ruminococcaceae UCG-011 and Butyrivibrio 2 and markers of browning in either retroperitoneal WAT or perirenal WAT. Overall, there are distinct relationships between the rumen microbiota, ruminal SCFAs and markers of WAT browning during the cold season in grazing Mongolian sheep.

Role of white adipose tissue browning in cold seasonal acclimation in grazing Mongolian sheep (Ovisaries).

Mongolian sheep are characteristically cold-tolerant and thus can survive well and maintain genetic stability in the extremely cold environment of the Mongolian Plateau. However, the adaptive mechanism of Mongolian sheep during the cold season in the plateau environment remains unknown. Browning of white adipose tissues (WAT) can trigger nonshivering thermogenesis as a potential strategy to promote an animal's tolerance to cold environments. Thus, a comparative analysis of the genes and proteins of uncoupling protein 1 (UCP1)-dependent and UCP1-independent browning pathways, mitochondrial biogenesis, lipogenic and lipolytic processes of WAT from grazing Mongolian sheep in the cold and warm seasons was conducted. We found seasonal browning of both retroperitoneal WAT and perirenal WAT, and the signalling of the process was mainly transduced by the UCP1- dependent pathway, primarily reflected in the upregulated gene levels of UCP1 and peroxisome proliferative activated receptor gamma coactivator 1 alpha (PGC-1α). In addition, the mean adipocyte diameter and mRNA expression of lipogenic genes in both interscapular WAT and subcutaneous WAT were significantly elevated during the cold season. The findings of this study demonstrate that grazing Mongolian sheep could depend on seasonal browning of both retroperitoneal WAT and perirenal WAT together with the expansion of both interscapular WAT and subcutaneous WAT to acclimate to cold environments of the Mongolian Plateau.

Secondary coronary artery ostial lesions: Three case reports.

BACKGROUND: Atherosclerosis is one of the main causes of coronary artery ostial lesions seen clinically. Secondary coronary artery ostial lesions are rare, and cases reported previously were associated with syphilitic vasculitis and aortic dissection. Here, we report three rare cases of secondary coronary ostial lesions. Due to their rareness, these lesions can easily be neglected, which may lead to misdiagnosis and missed diagnosis. CASE SUMMARY: We present three patients with acute myocardial infarction and unstable angina caused by secondary coronary artery ostial lesions. In Case 1, coronary angiography (CAG) revealed 90% stenosis of the left main coronary ostium. Chest contrast computed tomography (CT) suggested thymic carcinoma invading the left main coronary ostium. Coronary artery bypass grafting and tumor resection were performed. In Case 2, echocardiography revealed a sinus of Valsalva aneurysm (SVA)-like dilatation. CAG showed a right coronary sinus giant aneurysm and complete obstruction of the right coronary artery (RCA) ostium. Aortic contrast CT confirmed these findings. The Bentall procedure was performed. In Case 3, CT CAG identified an anomalous origin of the right coronary artery (AORCA) from the left sinus of Valsalva coursing between the aorta and pulmonary trunk, causing severe RCA ostium stenosis by compression. Surgical correction of the AORCA was performed. CONCLUSION: The cases reported here suggest that we should consider other causes of coronary ostial lesions other than atherosclerosis.

Pretreatment of nucleus pulposus mesenchymal stem cells with appropriate concentration of H2O2 enhances their ability to treat intervertebral disc degeneration.

BACKGROUND: Nucleus pulposus mesenchymal stem cells (NPMSCs) transplantation is a promising treatment for intervertebral disc degeneration (IVDD). However, the transplanted NPMSCs exhibited weak cell proliferation, high cell apoptosis, and a low ability to resist the harsh microenvironment of the degenerated intervertebral disc. There is an urgent need to explore feasible methods to enhance the therapeutic efficacy of NPMSCs transplantation. OBJECTIVE: To identify the optimal concentration for NPMSCs pretreatment with hydrogen peroxide (H2O2) and explore the therapeutic efficacy of NPMSCs transplantation using H2O2 pretreatment in IVDD. METHODS: Rat NPMSCs were pretreated with different concentrations (range from 25 to 300 µM) of H2O2. The proliferation, reactive oxygen species (ROS) level, and apoptosis of NPMSCs were detected by cell counting kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) staining, and flow cytometry in vitro. The underlying signalling pathways were explored utilizing Western blotting. A rat needle puncture-stimulated IVDD model was established. X-ray, histological staining, and a multimode small animal live imaging system were used to evaluate the therapeutic effect of H2O2-pretreated NPMSCs in vivo. RESULTS: NPMSCs pretreated with 75 µM H2O2 demonstrated the strongest elevated cell proliferation by inhibiting the Hippo pathway (P < 0.01). Meanwhile, 75 µM H2O2-pretreated NPMSCs exhibited significantly enhanced antioxidative stress ability (P < 0.01), which is related to downregulated Brd4 and Keap1 and upregulated Nrf2. NPMSCs pretreated with 75 µM H2O2 also exhibited distinctly decreased apoptosis (P < 0.01). In vivo experiments verified that 75 µM H2O2-pretreated NPMSCs-transplanted rats exhibited an enhanced disc height index (DHI% = 90.00 ± 4.55, P < 0.01) and better histological morphology (histological score = 13.5 ± 0.5, P < 0.01), which means 75 µM H2O2-pretreated NPMSCs can better adapt to the environment of degenerative intervertebral discs and promote the repair of IVDD. CONCLUSIONS: Pretreatment with 75 µM H2O2 was the optimal concentration to improve the proliferation, antioxidative stress, and antiapoptotic ability of transplanted NPMSCs, which is expected to provide a new feasible method to improve the stem cell therapy efficacy of IVDD.

Baicalein Preconditioning Cardioprotection Involves Pro-Oxidant Signaling and Activation of Pyruvate Dehydrogenase.

Preconditioning has a powerful protective potential against myocardial ischemia-reperfusion injury (I/R). Our prior work demonstrated that baicalein, a flavonoid derived from the root of Scatellaria baicalensis Georgi (also known as Huangqin), confers this preconditioning protection. This study further explored the mechanisms of baicalein preconditioning (BC-PC) in mouse cardiomyocytes. Cells were treated with baicalein (10 µM) for a brief period of time (10 min) prior to simulated ischemia 90 min/reperfusion for 180 min. Baicalein triggered an induction of a small amount of mitochondrial reactive oxygen species (ROS) prior to the initiation of ischemia, assessed by 6-carboxy-2', 7'-dichlorodihydrofluorescein diacetate (6-carboxy-H2DCFDA). It also significantly increased cell viability measured by propidium iodide (PI) and lactate dehydrogenase and preserved mitochondrial membrane potential assessed by TMRM fluorescence intensity. Myxothiazol, a mitochondrial electron transport chain complex III inhibitor, partially blocked ROS generation induced by BC-PC and reduced cell viability. BC-PC increased phosphorylation of Akt (Thr308 and Ser473) and eNOS Ser1177, and nitric oxide (NO) production measured using 4,5-diaminofluorescein diacetate (DAF-2 DA, 1 µM). Akt inhibitor API-2 abolished Akt phosphorylation and reduced DAF-2 production and cell viability. In addition, BC-PC decreased phosphorylation of pyruvate dehydrogenase (PDH) reflecting upregulated PDH activity, and increased ATP production at 30 min during reperfusion. Taken together, baicalein preconditioning-induced cardioprotection involves pro-oxidant generation, activates survival signaling Akt/eNOS/NO, and improves metabolic recovery after I/R injury. Our work provides new perspectives on the effect of baicalein on cardiac preconditioning against I/R injury.

Does MIS-TLIF or TLIF result in better pedicle screw placement accuracy and clinical outcomes with navigation guidance?

BACKGROUND: Although previous studies have suggested that navigation can improve the accuracy of pedicle screw placement, few studies have compared navigation-assisted transforaminal lumbar interbody fusion (TLIF) and navigation-assisted minimally invasive TLIF (MIS-TLIF). The entry point of pedicle screw insertion in navigation-assisted MIS-TLIF (NM-TLIF) may deviate from the planned entry point due to an uneven bone surface, which may result in misplacement. The purpose of this study was to explore the pedicle screw accuracy and clinical consequences of MIS-TLIF and TLIF, both under O-arm navigation, to determine which surgical method is better. METHODS: A retrospective study of 54 patients who underwent single-segment NM-TLIF or navigation-assisted TLIF (N-TLIF) was conducted. In addition to the patients' demographic characteristics, intraoperative indicators and complications, the Oswestry Disability Index (ODI) and visual analog scale (VAS) score were recorded and analyzed preoperatively and at the 1-, 6-, and 12-month and final postoperative follow-ups. The clinical qualitative accuracy and absolute quantitative accuracy of pedicle screw placement were assessed by postoperative CT. Multifidus muscle injury was evaluated by T2-weighted MRI. RESULTS: Compared with N-TLIF, NM-TLIF was more advantageous in terms of the incision length, intraoperative blood loss, drainage volume, time to ambulation, length of hospital stay, blood transfusion rate and analgesia rate (P < 0.05). The ODI and VAS scores for low back pain were better than those of N-TLIF at 1 month and 6 months post-surgery (P < 0.05). There was no significant difference in the clinical qualitative screw placement accuracy (97.3% vs. 96.2%, P > 0.05). The absolute quantitative accuracy results showed that the axial translational error, sagittal translational error, and sagittal angle error in the NM-TLIF group were significantly greater than those in the N-TLIF group (P < 0.05). The mean T2-weighted signal intensity of the multifidus muscle in the NM-TLIF group was significantly lower than that in the N-TLIF group (P < 0.05). CONCLUSIONS: Compared with N-TLIF, NM-TLIF has the advantages of being less invasive, yielding similar or better screw placement accuracy and achieving better symptom relief in the midterm postoperative recovery period. However, more attention should be given to real-time adjustment for pedicle insertion in NM-TLIF rather than just following the entry point and trajectory of the intraoperative plan.

The accuracy and effectiveness of automatic pedicle screw trajectory planning based on computer tomography values: an in vitro osteoporosis model study.

BACKGROUND: Pedicle screw placement in patients with osteoporosis is a serious clinical challenge. The bone mineral density (BMD) of the screw trajectory has been positively correlated with the screw pull-out force, while the computer tomography (CT) value has been linearly correlated with the BMD. The purpose of this study was to establish an in vitro osteoporosis model and verify the accuracy and effectiveness of automated pedicle screw planning software based on CT values in this model. METHODS: Ten vertebrae (L1-L5) of normal adult pigs were randomly divided into decalcification and control groups. In the decalcification group, the vertebral bodies were decalcified with Ethylenediaminetetraacetic acid (EDTA) to construct an in vitro osteoporosis model. In the decalcification group, automatic planning (AP) and conventional manual planning (MP) were used to plan the pedicle screw trajectory on the left and right sides of the pedicle, respectively, and MP was used on both sides of the control group. CT values of trajectories obtained by the two methods were measured and compared. Then, 3D-printed guide plates were designed to assist pedicle screw placement. Finally, the pull-out force of the trajectory obtained by the two methods was measured. RESULTS: After decalcification, the BMD of the vertebra decreased from - 0.03 ± 1.03 to - 3.03 ± 0.29 (P < 0.05). In the decalcification group, the MP trajectory CT value was 2167.28 ± 65.62 Hu, the AP trajectory CT value was 2723.96 ± 165.83 Hu, and the MP trajectory CT value in the control group was 2242.94 ± 25.80 Hu (P < 0.05). In the decalcified vertebrae, the screw pull-out force of the MP group was 48.6% lower than that of the control group (P < 0.05). The pull-out force of the AP trajectory was 44.7% higher than that of the MP trajectory (P < 0.05) and reached 97.4% of the MP trajectory in the control group (P > 0.05). CONCLUSION: Automatic planning of the pedicle screw trajectory based on the CT value can obtain a higher screw pull-out force, which is a valuable new method of pedicle screw placement in osteoporotic vertebre.

Efficacy and safety of transcutaneous auricular vagus nerve stimulation combined with conventional rehabilitation training in acute stroke patients: a randomized controlled trial conducted for 1 year involving 60 patients.

Transcutaneous auricular vagus nerve stimulation (ta-VNS) is a novel noninvasive treat-ment for stroke that directly stimulates the peripheral auricular branch of the vagus nerve. There have been recent reports that ta-VNS combined with conventional rehabilitation training promotes the recovery of neurological function of patients with acute stroke. However, these were small-sample-sized studies on the recovery of neurological function in patients after percutaneous vagus nerve stimulation in the subacute and chronic phases after stroke. This double-blinded randomized controlled trial involved 60 acute ischemic or hemorrhagic stroke patients aged 18-80 years who received treatment in the Second Affiliated Hospital of Chongqing Medical University. The subjects were randomly assigned to receive ta-VNS or sham ta-VNS combined with conventional rehabilitation training. The follow-up results over 1 year revealed that ta-VNS combined with conventional rehabilitation training greatly improved the recovery of motor and sensory functions and emotional responses compared with sham ta-VNS combined with conventional rehabilitation training. There were no obvious side effects. These findings suggest that ta-VNS combined with conventional rehabilitation training for the treatment of acute ischemic or hemorrhagic stroke patients is safe and effective.

The biological effect of cobalt chloride mimetic-hypoxia on nucleus pulposus cells and the comparability with physical hypoxia in vitro.

Objective: Nucleus pulposus cells (NPCs) are cells extracted from the intervertebral disc and are important for research into intervertebral disc degeneration (IVDD). NPCs live in an avascular and relatively hypoxic environment. Cobalt chloride (CoCl2) has been used in many cell studies to mimic hypoxia. The objective of this study was to explore the possibility of using CoCl2 to induce mimetic-hypoxia for NPCs and the comparison with hypoxia (1% O2) in vitro. Materials and methods: Rat nucleus pulposus cells of Passage 3-5 were used in this research. Cell viability, rate of cell apoptosis, ROS (reactive oxygen species) generation, cell migration, extracellular pH and extracellular matrix metabolism were determined to compare the influence of hypoxia (1% O2) and CoCl2 on NPCs. Results: We found that the effects of CoCl2 on NPCs was dose-dependent. At the proper concentration, CoCl2 could be used to elicit chemical hypoxia for nucleus pulposus cells in vitro and many biological effects, analogous to physical hypoxia (1% O2), could be achieved such as enhanced cell viability, decreased apoptosis and activated extracellular matrix metabolism. On the other hand, CoCl2 mimetic-hypoxia did not affect NPCs glycolysis and migration compared to physical hypoxia. In addition, high concentration of CoCl2 (>200 µM) is harmful to NPCs with high rates of apoptosis and ECM (extracellular matrix) degradation. Conclusions: It is feasible and convenient to use CoCl2 to induce chemical mimetic hypoxia for culturing NPCs on the premise of appropriate concentration. But in aspects of cell migration and glycolysis, CoCl2 could not achieve similar results with physical hypoxia. This study may provide a convenient method and enlightenment to induce mimetic-hypoxia for researchers studying NPCs and IVVD.

Roles of multimodal intra-operative neurophysiological monitoring (IONM) in percutaneous endoscopic transforaminal lumbar interbody fusion: a case series of 113 patients.

BACKGROUND: Despite the wide use of intraoperative neurophysiological monitoring (IONM) in spinal surgeries, the efficacy of IONM during percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) surgery in detecting postoperative neurological deficits has not been well characterized. METHODS: MIONM data from 113 consecutive patients who underwent PE-TLIF surgeries between June 2018 and April 2020 were retrospectively reviewed. Postoperative neurological deficits were documented and analyzed, and the efficacy and specificity of various IONM techniques were compared. RESULTS: Of the 113 consecutive patients, 12 (10.6%) with IONM alerts were identified. The MIONM sensitivity and specificity were 100 and 96.2%, respectively. The frequency of neurological complications, including minor deficits, was 6.2% (n = 7); all of the neurological complications were temporary. The ability of single IONM modalities to detect neurological complications varied between 25.0 and 66.6%, whereas that of all modalities was 100%. CONCLUSIONS: MIONM is more effective and accurate than unimodal monitoring in assessing nerve root function during PE-TLIF surgeries, reducing both neurological complications and false-negative findings. We recommend MIONM in PE-TLIF surgeries.

Novel through-the-scope twin clip for the closure of GI wounds: the first experimental survival study in pigs (with videos).

BACKGROUND AND AIMS: We developed a through-the-scope twin clip (TTS-TC) for closing GI wounds. The objective of this study was to evaluate the efficacy and safety of the TTS-TC in GI wound closure. METHODS: GI nonperforating and perforating wounds (≥2.5 cm) were created in live pigs. TTS-TCs were used to convert the large wounds into small wounds. The remaining small wounds were closed using conventional through-the-scope clips (TTSCs). The follow-up period was 1 month. Location and size of the wound, time of wound closure, intraoperative and postoperative adverse events, and conditions of wound healing were investigated. RESULTS: Thirteen wounds were created in 5 live pigs, including 2 gastric nonperforating and 3 perforating wounds and 5 large intestinal nonperforating and 3 perforating wounds. The mean long and short diameters of the wounds were 4.1 (± .9) cm and 3.4 (± .7) cm, respectively. All wounds were successfully closed using the TTS-TCs combined with TTSCs. The total mean time for wound closure was 9.2 (± 5.3) minutes, and the mean time for using the TTS-TCs was 3.9 (± 4.7) minutes. During the 1-month follow-up period, no bleeding, perforation, or death occurred; all wounds healed with scar formation; and all TTS-TCs detached spontaneously. CONCLUSIONS: The TTS-TC was successfully used to close large-sized GI wounds. The TTS-TC is a promising tool for large-size wound closure under flexible endoscopy.

Vagal Nerve Stimulation Protects Against Cerebral Ischemia-Reperfusion Injury in Rats by Inhibiting Autophagy and Apoptosis.

BACKGROUND: Cumulative evidence suggests that neuronal death including autophagy, apoptosis, and necrosis is closely related to the occurrence and development of cerebral ischemia-reperfusion (I/R) injury. Moreover, vagal nerve stimulation (VNS) is involved in many different neuroprotective and neuroplasticity pathways. Thus, VNS may be a novel approach for treating various neurodegenerative diseases. The present study aims to determine whether VNS protects against cerebral I/R injury in rats by inhibiting autophagy and apoptosis. METHODS: Cerebral I/R injury is induced by middle cerebral artery occlusion (MCAO) and VNS is carried out. Infarct volume, neurological deficit, autophagy, and apoptosis are examined 24 h after reperfusion. RESULTS: Vagal nerve stimulation decreases infarct volume and suppresses neurological deficit. Moreover, obvious autophagy and apoptosis are detected in rats that have undergone I/R, and VNS inhibits autophagy and apoptosis. CONCLUSION: Vagal nerve stimulation exerts neuroprotective effects following I/R injury by inhibiting autophagy and apoptosis.