Gene expression profiling in nucleus pulposus of human ruptured lumbar disc herniation

Purpose: To examine the differences in gene expression between ruptured and non-ruptured nucleus pulposus tissues of the intervertebral discs using gene chip technology. Methods: A total of 8 patients with nucleus pulposus from a lumbar disc herniation (LDH) undergoing discectomy in our hospital were selected, including 4 ruptured and 4 non-ruptured herniated nucleus pulposus cases. Total RNA was extracted from cells by using TRIzol reagent. Nucleus pulposus cDNA probes of the two groups were obtained by the single marker method and hybridized with a human gene expression profiling chip (Agilent). The fluorescence signal images were scanned by a laser, and the obtained genes were analyzed by bioinformatics. Results: There were 75 differentially expressed genes with more than 2-fold-changes, of which 56 were up-regulated and 19 were down-regulated. The differential expression of THSD7A, which was up-regulated 18 times, was the most significant, followed by CCL5, AQP3 and SDC4. Conclusion: THSD7A can be used as a characteristic differentially expressed gene in human ruptured nucleus pulposus. Moreover, CCL5, AQP3 and SDC4 may improve the chemotaxis of stem cell migration for self-healing of damaged disc tissue, increase water uptake by nucleus accumbens cells, and inhibit the inflammatory response, thus delaying the process of intervertebral disc degeneration.

First-Principles Study on the Structural, Electronic, and Lithium Storage Properties of Ti3C2T2 (T = O, F, H, OH) MXene

The structures of bare Ti₃C₂ and functionalized Ti₃C₂T₂ (T = O, F, H, OH) MXenes were constructed, and the effect of surface functional groups T₂ (T = O, F, H, OH) on the structural, electronic, and lithium storage properties were investigated by first-principles calculations. The results show that the proximity of surface functional groups will induce some lattice distortion of Ti₃C₂T₂ MXene. The degree of lattice distortion depends mainly on the adsorption position of functional groups and the types of surface functional groups. From the point of view of forming energy, the surface functional groups tend to be located at the CCP site. From the energy band and DOS results, the presence of surface functional groups has a significant effect on the valence band, while it has a slight impact on the conduction band. In terms of lithium storage, lithium atom adsorption starts from the HCP position for bare Ti₃C₂, while functionalized Ti₃C₂T₂ starts from the CCP position. The double-layer lithium storage capacity of bare Ti₃C₂ and Ti₃C₂O₂ were 639.78 mAh/g and 537.22 mAh/g, respectively. And the single-layer lithium storage capacity of Ti₃C₂F₂ was 130.77 mAh/g.

Tumor factors stimulate lysosomal degradation of tumor antigens and undermine their cross-presentation in lung cancer

Activities of dendritic cells (DCs) that present tumor antigens are often suppressed in tumors. Here we report that this suppression is induced by tumor microenvironment-derived factors, which activate the activating transcription factor-3 (ATF3) transcription factor and downregulate cholesterol 25-hydroxylase (CH25H). Loss of CH25H in antigen presenting cells isolated from human lung tumors is associated with tumor growth and lung cancer progression. Accordingly, mice lacking CH25H in DCs exhibit an accelerated tumor growth, decreased infiltration and impaired activation of intratumoral CD8+ T cells. These mice do not establish measurable long-term immunity against malignant cells that undergo chemotherapy-induced immunogenic cell death. Mechanistically, downregulation of CH25H stimulates membrane fusion between endo-phagosomes and lysosomes, accelerates lysosomal degradation and restricts cross-presentation of tumor antigens in the intratumoral DCs. Administration of STING agonist MSA-2 reduces the lysosomal activity in DCs, restores antigen cross presentation, and increases therapeutic efficacy of PD-1 blockade against tumour challenge in a CH25H-dependent manner. These studies highlight the importance of downregulation of CH25H in DCs for tumor immune evasion and resistance to therapy.

Clinical feasibility of deep learning-based automatic head CBCT image segmentation and landmark detection in computer-aided surgical simulation for orthognathic surgery

The purpose of this ambispective study was to investigate whether deep learning-based automatic segmentation and landmark detection, the SkullEngine, could be used for orthognathic surgical planning. Sixty-one sets of cone beam computed tomography (CBCT) images were automatically inferred for midface, mandible, upper and lower teeth, and 68 landmarks. The experimental group included automatic segmentation and landmarks, while the control group included manual ones that were previously used to plan orthognathic surgery. The qualitative analysis of segmentation showed that all of the automatic results could be used for computer-aided surgical simulation. Among these, 98.4% of midface, 70.5% of mandible, 98.4% of upper teeth, and 93.4% of lower teeth could be directly used without manual revision. The Dice similarity coefficient was 96% and the average symmetric surface distance was 0.1 mm for all four structures. With SkullEngine, it took 4 minutes to complete the automatic segmentation and an additional 10 minutes for a manual touchup. The results also showed the overall mean difference between the two groups was 2.3 mm for the midface and 2.4 mm for the mandible. In summary, the authors believe that automatic segmentation using SkullEngine is ready for daily practice. However, the accuracy of automatic landmark digitization needs to be improved.

Inherent regional brain activity changes in male obstructive sleep apnea with mild cognitive impairment: A resting-state magnetic resonance study

Obstructive sleep apnea (OSA) is the most common sleep disorder worldwide. Previous studies have shown that OSA patients are often accompanied by cognitive function loss, and the underlying neurophysiological mechanism is still unclear. This study aimed to determine whether there are differences in regional homogeneity (Reho) and functional connectivity (FC) across the brain between OSA patients with MCI (OSA-MCI) and those without MCI (OSA-nMCI) and whether such differences can be used to distinguish the two groups. Resting state magnetic resonance data were collected from 48 OSA-MCI patients and 47 OSA-nMCI patients. The brain regions with significant differences in Reho and FC between the two groups were identified, and the Reho and FC features were combined with machine learning methods for classification. Compared with OSA-nMCI patients, OSA-MCI patients showed significantly lower Reho in bilateral lingual gyrus and left superior temporal gyrus. OSA-MCI patients also showed significantly lower FC between the bilateral lingual gyrus and bilateral cuneus, left superior temporal gyrus and left middle temporal gyrus, middle frontal gyrus, and bilateral posterior cingulate/calcarine/cerebellar anterior lobe. Based on Reho and FC features, logistic regression classification accuracy was 0.87; sensitivity, 0.70; specificity, 0.89; and area under the curve, 0.85. Correlation analysis showed that MoCA scale score in OSA patients was significant positive correlation sleep efficiency and negatively correlation with neck circumference. In conclusion, our results showed that the OSA-MCI group showed decreased Reho and FC in specific brain regions compared with the OSA-nMCI group, which may help to understand the underlying neuroimaging mechanism of OSA leading to cognitive dysfunction and may serve as a potential biomarker to distinguish whether OSA is accompanied by cognitive impairment.

Naringin regulates mitochondrial dynamics to protect against acetaminophen-induced hepatotoxicity by activating the AMPK/Nrf2 signaling pathway in vitro

Naringin (Nar) has been reported to exert potential hepatoprotective effects against acetaminophen (APAP)-induced injury. Mitochondrial dysfunction plays an important role in APAP-induced liver injury. However, the protective mechanism of Nar against mitochondrial damage has not been elucidated. Therefore, the aim of this study was to investigate the hepatoprotective effects of Nar against APAP and the possible mechanisms of actions. Primary rat hepatocytes and HepG2 cells were utilized to establish an in vitro model of APAP-induced hepatotoxicity. The effect of APAP and Nar on cell viability was evaluated by a CCK8 assay and detection of the concentrations of alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase. The cellular concentrations of biomarkers of oxidative stress were measured by ELISA. The mRNA expression levels of APAP-related phase II enzymes were determined by real-time PCR. The protein levels of Nrf2, phospho (p)-AMPK/AMPK, and biomarkers of mitochondrial dynamics were determined by western blot analysis. The mitochondrial membrane potential (MMP) was measured by high-content analysis and confocal microscopy. JC-1 staining was performed to evaluate mitochondrial depolarization. Nar pretreatment notably prevented the marked APAP-induced hepatocyte injury, increases in oxidative stress marker expression, reductions in the expression of phase II enzymes, significant loss of MMP, mitochondrial depolarization, and mitochondrial fission in vitro. In conclusion, Nar alleviated APAP-induced hepatocyte and mitochondrial injury by activating the AMPK/Nrf2 pathway to reduce oxidative stress in vitro. Applying Nar for the treatment of APAP-induced liver injury might be promising.

PSVIII-19 Predict Indigestible Fiber Fraction of Barley Plant Silage by Using non-Destructive Mid-IR vs Near-IR Spectroscopic Techniques

The objective of this study was to reveal the potential of using Fourier transform mid-infrared (FTIR) and near infrared (NIR) spectroscopy as tools for the determination of indigestible neutral (NDF) fraction (iNDF) of barley plant silage. A total of 48 barley plant silage samples collected from different farms in Western Canada provinces were analyzed for iNDF. Reference values were matched with NIR and FTIR spectra. Spectral data processing (pretreatments) included first derivative (FD), standard normal variate (SNV), multiplicative scattering correction (MSC), second derivative (SD) and orthogonal signal correction (OSC). Prediction equations were obtained from each model using an external validation set. The determination coefficient of external validation (R2P) of iNDF was 0.62 for FTIR, while 0.41 for NIR and the corresponding ratio performance deviation (RPD) were 1.69 and 1.38 in FTIR and NIR, respectively. Results from this research showed the high potential of applying infrared molecular spectroscopy for the examination of forage plant fiber digestibility. More studies are needed to improve the accuracy and performance of FTIR and NIR spectroscopies in predicting the iNDF of barley plant silage samples.

PSXIII-12 Characterization of Physiochemical and Nutrient Profiles of Feedstock and co-Products from Canola bio-oil Processing in Ruminants: Impacted by Source Origin

The objective of this study was to characterize physiochemical and nutrient profiles of feedstock and co-products from canola processing that were impacted by source origin to compare feedstocks and co-products (mash and pellet) from five different bio-oil processing plants with five batches of samples in each processing plant in Canada (CA) and in China (CH) collected by the Canola Council of Canada (CCC). The detailed physicochemical and nutrients parameters for ruminants were determined in chemical composition, TDN and truly digestible nutrients, energy profile (ME, NE), and protein and carbohydrate subfractions and their degradation and digestion in dairy cows. The data were analyzed using the Mixed model procedure in SAS 9.4 with RCBD. The treatment differences were compared using Tukey method. The results showed CP was greater in CH meals (P=0.003). The EE was not different between CA and CH (P >0.05). TDN1x was similar in canola meals regardless of the country (P >0.05). CH meals and feedstock had greater tdCP and tdNDF than CA (P< 0.05), while CA had greater tdNFC (P< 0.05). The energy values of ME3x, NELp3x, NEm3x, and NEg3x were similar in canola meals from both countries (P >0.05). No differences were observed in the energy profile of feedstock between CA and CH (P >0.05). The results also showed that pelleting affected the protein fractionation of CA canola meals (P< 0.05). Canola meals were different between CA and CH in the soluble (PA2) and slowly degradable fractions (PB2) (P< 0.05). The carbohydrate fractions of soluble fiber (CB2), digestible fiber (CB3), and indigestible fiber (CC) were different among CH meals (P< 0.05). CH presented greater water-soluble carbohydrate (CA4, P=0.04) and less CB2 (P=0.01) and CC (P< 0.001) than CA canola meals. Although the seeds were similar within and between counties, the oil-extraction process and pelleting seemed to have generated some different aspects on the meals in both countries.

PSI-18 Effect of Heat Processing Methods on Carbohydrate Subfractions and Degradation in Relation to Carbohydrate Molecular Spectral Profile of Barley Grain Using Advanced Molecular Spectroscopy in Ruminants

To our knowledge, there are few studies on the association between carbohydrate molecular structure spectral profiles of barley grain and ruminant-relevant nutritional characteristics. This study aimed to study associate processing-induced changes in carbohydrate molecular structure with changes in ruminant-relevant carbohydrate nutritional profiles. The heat processing methods included: dry roasting, autoclaving, and microwave irradiation. The ruminant-relevant carbohydrate nutritional profiles were determined which included carbohydrate chemical profiles, carbohydrate subfractions, ruminant-relevant carbohydrate digestion. The molecular structure spectral profiles were determined using vibrational molecular spectroscopy (ATR-FT/IR). The results showed that heat related processing significantly induced carbohydrate molecular spectral profiles. The heat related processing also significantly changed ruminant-relevant nutritional characteristics. There was an association between processing induced carbohydrate molecular structure changes and ruminant-relevant carbohydrate nutritional profiles. The advanced vibrational molecular spectroscopic technique (ATR-FTIR) shows the great potential as a fast analytical tool to predict ruminant-relevant carbohydrate nutritional characteristics.

Mitochondrial fragmentation in liver cancer: Emerging player and promising therapeutic opportunities

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related death worldwide. Enhanced mitochondrial fragmentation (MF) is associated with poor prognosis in HCC patients. However, its molecular mechanism in HCC remains elusive. Although enhanced MF activates effector T cells and dendritic cells, it induces immunoescape by decreasing the number and cytotoxicity of natural killer cells in the HCC immune microenvironment. Therefore, the influence of MF on the activity of different immune cells is a great challenge. Enhanced MF contributes to maintaining stemness by promoting the asymmetric division of liver cancer stem cells (LCSCs), suggesting that MF may become a potential target for HCC recurrence, metastasis, and chemotherapy resistance. Moreover, mechanistic studies suggest that MF may promote tumour progression through autophagy, oxidative stress, and metabolic reprogramming. Human-induced hepatocyte organoids are a recently developed system that can be genetically manipulated to mimic cancer initiation and identify potential preventive treatments. We can use it to screen MF-related candidate inhibitors of HCC progression and further explore the role of MF in hepatocarcinogenesis. We herein describe the mechanisms by which MF contributes to HCC development, discuss potential therapeutic approaches, and highlight the possibility that MF modulation has a synergistic effect with immunotherapy.

Dynamic regional homogeneity alterations and cognitive impairment in patients with moderate and severe obstructive sleep apnea

Background and purpose

Previous studies have found that abnormal local spontaneous brain activity in patients with obstructive sleep apnea (OSA) was associated with cognitive impairment, and dynamic functional connections can capture the time changes of functional connections during magnetic resonance imaging acquisition. The purpose of this study was to investigate the dynamic characteristics of regional brain connectivity and its relationship with cognitive function in patients with OSA and to explore whether the dynamic changes can be used to distinguish them from healthy controls (HCs).

Methods

Seventy-nine moderate and severe male OSA patients without any treatment and 84 HCs with similar age and education were recruited, and clinical data and resting functional magnetic resonance imaging data were collected. The dynamic regional homogeneity (dReHo) was calculated using a sliding window technique, and a double-sample t-test was used to test the difference in the dReHo map between OSA patients and HCs. We explored the relationship between dReHo and clinical and cognitive function in OSA patients using Pearson correlation analysis. A support vector machine was used to classify the OSA patients and HCs based on abnormal dReHo.

Result

Compared with HCs, OSA patients exhibited higher dReHo values in the right medial frontal gyrus and significantly lower dReHo values in the right putamen, right superior temporal gyrus, right cingulate gyrus, left insula and left precuneus. The correlation analysis showed that the abnormal dReHo values in multiple brain regions in patients with OSA were significantly correlated with nadir oxygen saturation, the oxygen depletion index, sleep period time, and Montreal cognitive assessment score. The support vector machine classification accuracy based on the dReHo difference in brain regions was 81.60%, precision was 81.01%, sensitivity was 81.01%, specificity was 82.14%, and area under the curve was 0.89.

Conclusion

The results of this study suggested that there was abnormal dynamic regional spontaneous brain activity in patients with OSA, which was related to clinical and cognitive evaluation and can be used to distinguish OSA patients from HCs. The dReHo is a potential objective neuroimaging marker for patients with OSA that can further the understanding of the neuropathological mechanism of patients with OSA.

Classification of severe obstructive sleep apnea with cognitive impairment using degree centrality: A machine learning analysis

In this study, we aimed to use voxel-level degree centrality (DC) features in combination with machine learning methods to distinguish obstructive sleep apnea (OSA) patients with and without mild cognitive impairment (MCI). Ninety-nine OSA patients were recruited for rs-MRI scanning, including 51 MCI patients and 48 participants with no mild cognitive impairment. Based on the Automated Anatomical Labeling (AAL) brain atlas, the DC features of all participants were calculated and extracted. Ten DC features were screened out by deleting variables with high pin-correlation and minimum absolute contraction and performing selective operator lasso regression. Finally, three machine learning methods were used to establish classification models. The support vector machine method had the best classification efficiency (AUC = 0.78), followed by random forest (AUC = 0.71) and logistic regression (AUC = 0.77). These findings demonstrate an effective machine learning approach for differentiating OSA patients with and without MCI and provide potential neuroimaging evidence for cognitive impairment caused by OSA.

Characteristics and mechanisms of resorption in lumbar disc herniation

Lumbar disc herniation (LDH) can be spontaneously absorbed without surgical treatment. However, the pathogenesis and physiological indications for predicting protrusion reabsorption are still unclear, which prevents clinicians from preferentially choosing conservative treatment options for LDH patients with reabsorption effects. The purpose of this review was to summarize previous reports on LDH reabsorption and to discuss the clinical and imaging features that favor natural absorption. We highlighted the biological mechanisms involved in the phenomenon of LDH reabsorption, including macrophage infiltration, inflammatory responses, matrix remodeling, and neovascularization. In addition, we summarized and discussed potential clinical treatments for promoting reabsorption. Current evidence suggests that macrophage regulation of inflammatory mediators, matrix metalloproteinases, and specific cytokines in intervertebral disc is essential for the spontaneous reabsorption of LDH.

Transcription-coupled donor DNA expression increases homologous recombination for efficient genome editing

Genomes can be edited by homologous recombination stimulated by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated peptide 9]-induced DNA double-strand breaks. However, this approach is inefficient for inserting or deleting long fragments in mammalian cells. Here, we describe a simple genome-editing method, termed transcription-coupled Cas9-mediated editing (TEd), that can achieve higher efficiencies than canonical Cas9-mediated editing (CEd) in deleting genomic fragments, inserting/replacing large DNA fragments and introducing point mutations into mammalian cell lines. We also found that the transcription on DNA templates is crucial for the promotion of homology-directed repair, and that tethering transcripts from TEd donors to targeted sites further improves editing efficiency. The superior efficiency of TEd for the insertion and deletion of long DNA fragments expands the applications of CRISPR for editing mammalian genomes.

Construction of the Skeleton of Lucidumone

The skeleton of lucidumone was constructed through oxidative dearomatization/intramolecular Diels-Alder reaction, Cu-mediated remote C-H hydroxylation, allyl oxidation, acid-promoted dynamic kinetic resolution cyclization, and benzylic oxidation.

Significant contribution of lightning NOx to summertime surface O3 on the Tibetan Plateau

Lightning generates nitrogen oxides (NO_x) in the troposphere, an important precursor of tropospheric ozone (O₃). The Tibetan Plateau (TP) is considered to be a global atmospheric background location with limited anthropogenic influences. However, the observed summertime surface O₃ concentration on the TP is 25% higher than that in highly polluted regions (e.g., southern China). Previous studies have suggested that lightning-produced NO_x (LNO_x) can affect the concentration of surface O₃. We used the Weather Research and Forecasting coupled with chemistry (WRF-Chem) model combined with satellite, ground-based, and airborne observations to evaluate the contribution of LNO_x to the surface O₃ budget on the TP. Our results showed that LNO_x contributed approximately 15% of the surface NO_x emission on the TP in summer. Accordingly, the contribution of LNO_x to the summertime surface daily maximum 8-h average (MDA8) O₃ on the TP was 9.3 ± 7.1 ppb, which was 17.5% ± 14.5% of the total concentration of the surface MDA8 O₃. In addition, our study found that the number of moles of NO produced per lightning flash (LNO_x production efficiency) significantly affected the surface concentration of NO_x, OH, and MDA8 O₃. Increasing the LNO_x production efficiency (PE) from 0 to 330 mol NO flash^-1 increased the concentration of MDA8 O₃ by up to 20% on the TP. Our study revealed that lightning significantly affects the atmospheric chemical processes involving O₃ on the TP.

Efficacy analysis of Cheng's GIRAFFE reconstruction after proximal gastrectomy for adenocarcinoma of esophagogastric junction

Objective

Reconstruction of the digestive tract for adenocarcinoma of esophagogastric junction (AEG) is in dispute. This study evaluated Cheng's gastric tube interposition esophagogastrostomy with reconstruction of His angle and fundus (Cheng's GIRAFFE anastomosis) in laparoscopic/open proximal gastrectomy for Siewert type II AEG, which was performed at Zhejiang Cancer Hospital and the First Affiliated Hospital of Zhejiang Chinese Medical University. Here, we discuss the preliminary results of gastric emptying and anti-reflux.

Methods

From a retrospective database, 74 patients with advanced Siewert type II AEG underwent curative proximal gastrectomy with GIRAFFE anastomosis, and their gastric emptying and anti-reflux outcomes were evaluated by the Reflux Disease Questionnaire (RDQ) score, nuclide gastric emptying, 24-h impedance-pH monitoring and gastroscopy.

Results

Seventy-four patients successfully completed proximal partial gastrectomy with Cheng's GIRAFFE esophagogastric anastomosis. RDQ score six months after the operation was 2.2±2.5. Results of nuclide gastric emptying examinations showed that the gastric half-emptying time was 67.0±21.5 min, the 1-h residual rate was (52.2±7.7)%, the 2-h residual rate was (36.4±5.1)%, and the 3-h residual rate was (28.8±3.6)%; 24-h impedance-pH monitoring revealed that the mean DeMeester score was 5.8±2.9. Reflux esophagitis was observed by gastroscopy in 7 patients six months after surgery.

Conclusions

Cheng's GIRAFFE anastomosis is safe and feasible for Siewert type II AEG.