Circ-0075305 hinders gastric cancer stem cells by indirectly disrupting TCF4-β-catenin complex and downregulation of SOX9

CircRNAs are covalently closed, single-stranded RNA that form continuous loops and play a crucial role in the initiation and progression of tumors. Cancer stem cells (CSCs) are indispensable for cancer development; however, the regulation of cancer stem cell-like properties in gastric cancer (GC) and its specific mechanism remain poorly understood. We elucidate the specific role of Circ-0075305 in GC stem cell properties. Circ-0075305 associated with chemotherapy resistance was identified by sequencing GC cells. Subsequent confirmation in both GC tissues and cell lines revealed that patients with high expression of Circ-0075305 had significantly better overall survival (OS) rates than those with low expression, particularly when treated with postoperative adjuvant chemotherapy for GC. In vitro and in vivo experiments confirmed that overexpression of Circ-0075305 can effectively reduce stem cell-like properties and enhance the sensitivity of GC cells to Oxaliplatin compared with the control group. Circ-0075305 promotes RPRD1A expression by acting as a sponge for corresponding miRNAs. The addition of LF3 (a β-catenin/TCF4 interaction antagonist) confirmed that RPRD1A inhibited the formation of the TCF4-β-catenin transcription complex through competitive to β-catenin and suppressed the transcriptional activity of stem cell markers such as SOX9 via the Wnt/β-catenin signaling pathway. This leads to the downregulation of stem cell-like property-related markers in GC. This study revealed the underlying mechanisms that regulate Circ-0075305 in GCSCs and suggests that its role in reducing β-catenin signaling may serve as a potential therapeutic candidate.

[Preliminary study on automatic quantification and grading of leopard spots fundus based on deep learning technology]

Objective: To achieve automatic segmentation, quantification, and grading of different regions of leopard spots fundus (FT) using deep learning technology. The analysis includes exploring the correlation between novel quantitative indicators, leopard spot fundus grades, and various systemic and ocular parameters. Methods: This was a cross-sectional study. The data were sourced from the Beijing Eye Study, a population-based longitudinal study. In 2001, a group of individuals aged 40 and above were surveyed in five urban communities in Haidian District and three rural communities in Daxing District of Beijing. A follow-up was conducted in 2011. This study included individuals aged 50 and above who participated in the second 5-year follow-up in 2011, considering only the data from the right eye. Color fundus images centered on the macula of the right eye were input into the leopard spot segmentation model and macular detection network. Using the macular center as the origin, with inner circle diameters of 1 mm, 3 mm, and outer circle diameter of 6 mm, fine segmentation of the fundus was achieved. This allowed the calculation of the leopard spot density (FTD) and leopard spot grade for each region. Further analyses of the differences in ocular and systemic parameters among different regions' FTD and leopard spot grades were conducted. The participants were categorized into three refractive types based on equivalent spherical power (SE): myopia (SE<-0.25 D), emmetropia (-0.25 D≤SE≤0.25 D), and hyperopia (SE>0.25 D). Based on axial length, the participants were divided into groups with axial length<24 mm, 24-26 mm, and>26 mm for the analysis of different types of FTD. Statistical analyses were performed using one-way analysis of variance, Kruskal-Wallis test, Bonferroni test, and Spearman correlation analysis. Results: The study included 3 369 participants (3 369 eyes) with an average age of (63.9±10.6) years; among them, 1 886 were female (56.0%) and 1, 483 were male (64.0%). The overall FTD for all eyes was 0.060 (0.016, 0.163); inner circle FTD was 0.000 (0.000, 0.025); middle circle FTD was 0.030 (0.000, 0.130); outer circle FTD was 0.055 (0.009, 0.171). The results of the univariate analysis indicated that FTD in various regions was correlated with axial length (overall: r=0.38, P<0.001; inner circle: r=0.31, P<0.001; middle circle: r=0.36, P<0.001; outer circle: r=0.39, P<0.001), subfoveal choroidal thickness (SFCT) (overall: r=-0.69, P<0.001; inner circle: r=-0.57, P<0.001; middle circle: r=-0.68, P<0.001; outer circle: r=-0.72, P<0.001), age (overall: r=0.34, P<0.001; inner circle: r=0.30, P<0.001; middle circle: r=0.31, P<0.001; outer circle: r=0.35, P<0.001), gender (overall: r=-0.11, P<0.001; inner circle: r=-0.04, P<0.001; middle circle: r=-0.07, P<0.001; outer circle: r=-0.11, P<0.001), SE (overall: r=-0.20; P<0.001; inner circle: r=-0.19, P<0.001; middle circle: r=-0.20, P<0.001; outer circle: r=-0.20, P<0.001), uncorrected visual acuity (overall: r=-0.18, P<0.001; inner circle: r=-0.26, P<0.001; middle circle: r=-0.24, P<0.001; outer circle: r=-0.22, P<0.001), and body mass index (BMI) (overall: r=-0.11, P<0.001; inner circle: r=-0.13, P<0.001; middle circle: r=-0.14, P<0.001; outer circle: r=-0.13, P<0.001). Further multivariate analysis results indicated that different region FTD was correlated with axial length (overall: β=0.020, P<0.001; inner circle: β=-0.022, P<0.001; middle circle: β=0.027, P<0.001; outer circle: β=0.022, P<0.001), SFCT (overall: β=-0.001, P<0.001; inner circle: β=-0.001, P<0.001; middle circle: β=-0.001, P<0.001; outer circle: β=-0.001, P<0.001), and age (overall: β=0.002, P<0.001; inner circle: β=0.001, P<0.001; middle circle: β=0.002, P<0.001; outer circle: β=0.002, P<0.001). The distribution of overall (H=56.76, P<0.001), inner circle (H=72.22, P<0.001), middle circle (H=75.83, P<0.001), and outer circle (H=70.34, P<0.001) FTD differed significantly among different refractive types. The distribution of overall (H=373.15, P<0.001), inner circle (H=367.67, P<0.001), middle circle (H=389.14, P<0.001), and outer circle (H=386.89, P<0.001) FTD differed significantly among different axial length groups. Furthermore, comparing various levels of FTD with systemic and ocular parameters, significant differences were found in axial length (F=142.85, P<0.001) and SFCT (F=530.46, P<0.001). Conclusions: The use of deep learning technology enables automatic segmentation and quantification of different regions of theFT, as well as preliminary grading. Different region FTD is significantly correlated with axial length, SFCT, and age. Individuals with older age, myopia, and longer axial length tend to have higher FTD and more advanced FT grades.

[Effects of human umbilical cord mesenchymal stem cells (MSCs)-derived exosomes on pulmonary vascular remodeling in hypoxic pulmonary hypertension]

The present study aimed to investigate the effect of human umbilical cord mesenchymal stem cells (MSCs)-derived exosomes (MSCs-Exo) on mice with hypoxic pulmonary hypertension (HPH). MSCs were isolated and cultured from human umbilical cords under aseptic conditions, and exosomes were extracted from the supernatants and identified. Healthy SPF C57BL/6 mice were randomly divided into three groups: normoxic group, hypoxic group, and hypoxic+MSCs-Exo group. Mice in the hypoxic group and the hypoxic+MSCs-Exo group were maintained for 28 d at an equivalent altitude of 5 000 m in a hypobaric chamber to establish HPH mouse model. The mice in the hypoxic+MSCs-Exo group were injected with MSCs-Exo via tail vein before hypoxia and on days 1, 3, 5 and 9 of hypoxia, and the mice in the other two groups were injected with PBS. At the end of the experiment, echocardiography was performed to detect pulmonary arterial acceleration time/pulmonary arterial ejection time ratio (PAAT/PET), right ventricular free wall thickness, and right ventricular hypertrophy index RV/(LV+S). HE staining was performed to observe the lung tissue morphology. EVG staining was performed to observe elastic fiber hyperplasia. Immunohistochemistry was performed to detect α smooth muscle actin (α-SMA) expression in lung tissue. Immunofluorescence staining was used to detect macrophage infiltration in lung tissue. qPCR was performed to detect IL-1β and IL-33 in lung tissue, and cytometric bead array was performed to detect IL-10 secretion. Western blotting was used to detect the M1 macrophage marker iNOS, M2 macrophage marker Arg-1 and IL-33/ST2 pathway proteins in lung tissues. The results showed that hypoxia increased pulmonary artery pressure and pulmonary vascular remodeling, increased macrophage infiltration, IL-1β and IL-33 expression (P < 0.05) and upregulated the IL-33/ST2 pathway (P < 0.05). Compared with the hypoxic group, MSCs-Exo treatment increased PAAT/PET (P < 0.05), decreased right ventricular free wall thickness (P < 0.05), right ventricular hypertrophy index RV/(LV+S) (P < 0.05), α-SMA expression in small pulmonary vessels (P < 0.05), and inflammatory factors including IL-1β and IL-33 expression in lung tissue, however increased IL-10 secretion (P < 0.05). In addition, MSCs-Exo treatment upregulated Arg-1 and downregulated iNOS and IL-33/ST2 (P < 0.05). The results suggest that MSC-Exo may alleviate HPH through their immunomodulatory effects.

[Properties of gelatin-polyethylene glycol hydrogel loaded with silver nanoparticle Chlorella and its effects on healing of infected full-thickness skin defect wounds in mice]

Objective: To explore the properties of gelatin-polyethylene glycol hydrogel loaded with silver nanoparticle (AgNP) Chlorella (hereinafter referred to as the composite hydrogel) and its effects on healing of infected full-thickness skin defect wounds in mice. Methods: The research was an experimental research. The simple gelatin-polyethylene glycol hydrogel (hereinafter referred to as the simple hydrogel) and the composite hydrogel were prepared, and the appearance and injectability of the two hydrogels were observed at 55 and 37 ℃, and under the irradiation of 808 nm near-infrared light, respectively. An electronic universal testing machine was employed to assess the tensile and compressive stress-strain properties of both types of hydrogels at room temperature. Additionally, the cyclic compressive stress-strain properties of the composite hydrogel were examined at 80% of the maximum compressive stress. Staphylococcus aureus or Escherichia coli solution was added to phosphate buffer solution (PBS), simple hydrogel, and composite hydrogel, respectively. The part of composite hydrogel containing Staphylococcus aureus or Escherichia coli solution was irradiated with near-infrared light for 5 minutes. After each sample was incubated for 6 h, the dilution plating method was used to detect and calculate the mortality rates of the two bacteria at 24 h of culture (n=5). The discarded foreskin tissue was taken from a 6-year-old healthy boy admitted to the Department of Urology of the First Affiliated Hospital of Naval Medical University for circumcision. Primary human fibroblasts (HFbs) were isolated using the enzyme extraction method, routinely cultured to the 3rd to 6th passages for subsequent cellular experiments. Composite hydrogel extracts with final mass concentrations of 100.0, 50.0, 25.0, 12.5, and 0 mg/mL were respectively prepared and used to culture HFbs, and the cell proliferation after 24 h of culture was detected using a cell counting kit 8 (n=3). A total of twenty 6-8 weeks old C57BL/6J female mice were utilized, and a full-thickness skin defect was surgically created on the back of each mouse. The wounds were infected with Staphylococcus aureus solution. The infected mice were divided into blank control group, simple hydrogel group, composite hydrogel group, and combined treatment group according to the random number table, and the wounds were treated with PBS, simple hydrogel, composite hydrogel, and composite hydrogel+light irradiation (under the irradiation of 808 nm near-infrared light for 5 min), respectively, with 5 mice in each group. On post injury day (PID) 0 (immediately after the first wound treatment), 3, 7, and 14, an overall assessment of wound exudation and healing were conducted, and the wound healing rates on PID 7 and 14 were calculated (n=5). On PID 14, hematoxylin-eosin staining was performed to observe histopathological changes in the mouse wound. Results: Both simple hydrogel and composite hydrogel were in a solution state at 55 ℃ and transition to a gel state when cooling to 37 ℃. After the two hydrogels were irradiated by near-infrared light, only the composite hydrogel reheated up and returned to the solution state again with injectability. The maximum tensile stress of the composite hydrogel was up to 301.42 kPa, with a corresponding strain of 87.19%; the maximum compressive stress was up to 413.79 kPa, with a corresponding strain of 91.67%, which was similar to the tensile and compressive properties of the simple hydrogel. After 10 compression cycles, the maximum compressive stress of the composite hydrogel still reached 84.1% of the first compressive stress. After 24 h of culture, the mortality rate of Staphylococcus aureus treated with simple hydrogel was significantly higher than that treated with PBS (P<0.05); the mortality rates of Escherichia coli and Staphylococcus aureus treated with composite hydrogel alone were significantly higher than those treated with simple hydrogel (P<0.05); the mortality rates of Escherichia coli and Staphylococcus aureus treated with composite hydrogel+light irradiation were significantly higher than those treated with composite hydrogel alone (P<0.05). After 24 h of culture, compared with that cultured in composite hydrogel immersion solution with final mass concentration of 0 mg/mL, the proliferation activity of HFbs cultured in composite hydrogel immersion solution with final mass concentrations of 25.0 and 50.0 mg/mL was significantly enhanced (P<0.05), while the proliferation activity of HFbs cultured in composite hydrogel immersion solution with final mass concentration of 100 mg/mL was significantly decreased (P<0.05). On PID 0 and 3, more purulent secretions were seen in the wounds of mice in blank control group and simple hydrogel group, while only a small amount of exudate was observed in the wounds of mice in composite hydrogel group, and no obvious infection was observed in the wounds of mice in combined treatment group. On PID 7 and 14, the wound healing rates of mice in simple hydrogel group were significantly higher than those in blank control group (P<0.05); the wound healing rates of mice in composite hydrogel group were significantly higher than those in simple hydrogel group (P<0.05); the wound healing rates in combined treatment group were significantly higher than those in composite hydrogel group (P<0.05). On PID 14, the wounds of mice in blank control group exhibited a high infiltration of inflammatory cells with no new epithelial layer observed; the wounds of mice in simple hydrogel group displayed a short length of newly formed epithelium with a small amount of inflammatory cells; the wounds of mice in composite hydrogel group exhibited continuous formation of new epithelium and a large amount of immature granulation tissue; the wounds of mice in combined treatment group showed continuous epithelialization with less immature granulation tissue. Conclusions: The prepared composite hydrogel exhibits excellent thermosensitivity, photothermal properties, and injectability, as well as excellent mechanical properties, antibacterial properties, and biocompatibility, and can promote the healing of infected full-thickness skin defect wounds in mice.

Exogenous Melatonin Alleviates Atrazine-Induced Glucose Metabolism Disorders in Mice Liver via Suppressing Endoplasmic Reticulum Stress

Atrazine (ATZ) is a widely used herbicide that has toxic effects on animals. Melatonin (MLT) is a natural hormone with strong antioxidant properties. However, the effect of MLT on the glucose metabolism disorder caused by ATZ is still unclear. Mice were divided into four groups randomly and given 21 days of gavage: blank control group (Con), 5 mg/kg MLT group (MLT), 170 mg/kg ATZ group (ATZ), and 170 mg/kg ATZ and 5 mg/kg MLT group (ATZ + MLT). The results show that ATZ alters mRNA levels of metabolic enzymes related to glycogen synthesis and glycolysis and increased metabolites (glycogen, lactate, and pyruvate). ATZ causes abnormalities in glucose metabolism in mouse liver, interfering with glycemia regulation ability. MLT can regulate the endoplasmic reticulum to respond to disordered glucose metabolism in mice liver. This study suggested that MLT has the power to alleviate the ATZ-induced glycogen overdeposition and glycolytic deficit.

Vertical transfer and functional characterization of cotton seed core microbiome

Introduction

Microbiome within plant tissues is pivotal for co-evolution with host plants. This microbiome can colonize the plant, with potential transmission via seeds between parents and offspring, affecting seedling growth and host plant adaptability to the environment.

Methods

We employed 16S rRNA gene amplicon analysis to investigate the vertical distribution of core microbiome in cotton seeds across ecological niches [rhizosphere, root, stem, leaf, seed and seed-P (parental seed)] of the three cotton genotypes.

Results

The findings demonstrated a significant decrease in microbiome diversity and network complexity from roots, stems, and leaves to seeds. The microenvironment exerted a more substantial influence on the microbiome structure of cotton than the genotypes. The core endophytic microorganisms in cotton seeds comprised 29 amplicon sequence variants (ASVs) affiliated with Acidimicrobiia, Alphaproteobacteria, Bacilli, Bacteroidia, Clostridia, Gammaproteobacteria, and unclassified_Proteobacteria. These vertically transmitted taxa are widely distributed in cotton plants. Through 16S rRNA gene-based function prediction analysis of the cotton microbiome, we preliminarily understood that there are potential differences in metabolic capabilities and phenotypic traits among microbiomes in different microhabitats.

Discussion

In conclusion, this study demonstrated the crucial role of the microenvironment in influencing the cotton microbiome and offered insights into the structures and functions of the cotton seed microbiome, facilitating future crop yield enhancement through core seed microbiome regulation.

Nanographene with a Nitrogen-Doped Cavity

Nitrogen-doped cavities are pervasive in graphenic materials, and represent key sites for catalytic and electrochemical activity. However, their structures are generally heterogeneous. In this study, we present the synthesis of a well-defined molecular cutout of graphene featuring N-doped cavity. The graphitization of a macrocyclic pyridinic precursor was achieved through photochemical cyclodehydrochlorination. In comparison to its counterpart with pyridinic nitrogen at the edges, the pyridinic nitrogen atoms in this nanographene cavity exhibit significantly reduced basicity and selective binding to Ag+ ion. Analysis of the protonation and coordination equilibria revealed that the tri-N-doped cavity binds three protons, but only one Ag+ ion. These distinct protonation and coordination behaviors clearly illustrate the space confinement effect imparted by the cavities.

Holistic Assessment Based On Hepatocyte Mitochondria: Lycopene Repairs Oxidized mtDNA to Alleviate Mitochondrial Stress Induced by Atrazine

Atrazine (ATZ) is a highly persistent herbicide that harms organism health. Lycopene (LYC) is an antioxidant found in plants and fruits. The aim of this study is to investigate the mechanisms of atrazine-induced mitochondrial damage and lycopene antagonism in the liver. The mice were divided into seven groups by randomization: blank control (Con group), vehicle control (Vcon group), 5 mg/kg lycopene (LYC group), 50 mg/kg atrazine (ATZ1 group), ATZ1+LYC group, 200 mg/kg atrazine (ATZ2 group), and ATZ2+LYC group. The present study performed a holistic assessment based on mitochondria to show that ATZ causes the excessive fission of mitochondria and disrupts mitochondrial biogenesis. However, the LYC supplementation reverses these changes. ATZ causes increased mitophagy and exacerbates the production of oxidized mitochondrial DNA (Ox-mtDNA) and mitochondrial stress. This study reveals that LYC could act as an antioxidant to repair Ox-mtDNA and restore the disordered mitochondrial function caused by ATZ.

[Analysis on the allocation equality in occupational health technology service resource in Gansu Province]

Objective: To investigate and analyze the allocation equality of occupational health technology service resource of Gansu disease control and prevention institutions, providing reference basis for optimizing the allocation of occupational health technology service resources. Methods: Combined with the survey data in September 2021, Gansu Province was divided into five economic regions by geographical location and economic characteristics. Taking the service number of enterprises and workers as the analysis dimensions, the allocation level of occupational health technology service resources in different regions was compared. The allocation equality was analyzed through Lorentz curve, Gini coefficient and Theil index. Results: There were 301 occupational health technicians and 1914 sampling and testing equipments of Gansu Provincial disease control and prevention institutions in 2021. All of the technicians and equipments were used for serving 1952 enterprises and 465800 workers. The curvature of Lorentz curves and Gini coefficient which measured by the service number of enterprises and workers were: occupational health technicians>radioactive factor sampling and testing equipment >physical factor sampling and testing equipment >chemical factor sampling and testing equipment, and chemical factor sampling and testing equipment>physical factor sampling and testing equipment >radioactive factor sampling and testing equipment >occupational health technicians, respectively. Theil index of occupational health technology service resources suggested that differences in regions were the main unfair reason effected the allocation of occupational health technicians and radioactive factor sampling and testing equipment, while the differences between regions were the main unfair reason effected the allocation of chemical and physical factor sampling and testing equipment. Conclusion: The allocation equality in occupational health technology service resources of Gansu Provincial disease control and prevention institutions was not enough, and the differences in regions and between regions should be considered. This study suggests that it is necessary to introduce more occupational health technicians. The allocation of occupational health technology service resources should match with the number of local enterprises and the types of potential hazard factors of enterprises as far as possible.

Investigating temperature-induced torque noise of a torsion pendulum based on temperature modulation at different frequencies

Torsion pendulums are widely used for the measurement of small forces. In this study, we investigated the impact of temperature fluctuations on a torsion pendulum using heating devices to modulate the environmental temperature at different specific frequencies. The response coefficient between the temperature variation and the torque of the torsion pendulum was found to vary at different frequencies, with values from 4 × 10-15 N mK-1 at 0.1 mHz to 3 × 10-13 N mK-1 at 10 mHz. A passive thermal-insulation system was used to reduce the torque response within this frequency band, which is dominated by temperature noise. The results demonstrate that this modulation method provides a useful way to independently investigate the noise in a torsion pendulum resulting from environmental temperature fluctuations over a wide frequency band.

[Comprehensive assessment of mismatch repair and microsatellite instability status in molecular classification of endometrial carcinoma]

Objective: To explore the concordance and causes of different mismatch repair (MMR) and microsatellite instability (MSI) detection results in endometrial carcinoma (EC) molecular typing. Methods: A total of 214 EC patients diagnosed from January 2021 to April 2023 were selected at the Department of Pathology, Peking University Third Hospital. The immunohistochemistry (IHC) results of MMR protein were reviewed. Tumor specific somatic mutations, MMR germline mutations, microsatellite scores and tumor mutation burden (TMB) were detected by next-generation sequencing (NGS) with multi-gene panel. Methylation-specific PCR was used to detect the methylation status of MLH1 gene promoter in cases with deficient MLH1 protein expression. In cases with discrepant results between MMR-IHC and MSI-NGS, the MSI status was detected again by PCR (MSI-PCR), and the molecular typing was determined by combining the results of TMB and MLH1 gene promoter methylation. Results: (1) In this study, there were 22 cases of POLE gene mutation subtype, 55 cases of mismatch repair deficient (MMR-d) subtype, 29 cases of p53 abnormal subtype, and 108 cases of no specific molecular profile (NSMP). The median age at diagnosis of MMR-d subtype (54 years old) and the proportion of aggressive histological types (40.0%, 22/55) were higher than those of NSMP subtype [50 years old and 12.0% (13/108) respectively; all P<0.05]. (2) Among 214 patients, MMR-IHC test showed that 153 patients were mismatch repair proficient (MMR-p), 49 patients were MMR-d, and 12 patients were difficult to evaluate directly. MSI-NGS showed that 164 patients were microsatellite stable (MSS; equal to MMR-p), 48 patients were high microsatellite instability (MSI-H; equal to MMR-d), and 2 patients had no MSI-NGS results because the effective sequencing depth did not meet the quality control. The overall concordance between MMR-IHC and MSI-NGS was 94.3% (200/212). All the 12 discrepant cases were MMR-d or subclonal loss of MMR protein by IHC, but MSS by NGS. Among them, 10 cases were loss or subclonal loss of MLH1 and (or) PMS2 protein. Three discrepant cases were classified as POLE gene mutation subtype. In the remaining 9 cases, 5 cases and 3 cases were confirmed as MSI-H and low microsatellite instability (MSI-L) respectively by MSI-PCR, 6 cases were detected as MLH1 gene promoter methylation and 7 cases demonstrated high TMB (>10 mutations/Mb). These 9 cases were classified as MMR-d EC. (3) Lynch syndrome was diagnosed in 27.3% (15/55) of all 55 MMR-d EC cases, and the TMB of EC with MSH2 and (or) MSH6 protein loss or associated with Lynch syndrome [(71.0±26.2) and (71.5±20.1) mutations/Mb respectively] were significantly higher than those of EC with MLH1 and (or) PMS2 loss or sporadic MMR-d EC [(38.2±19.1) and (41.9±24.3) mutations/Mb respectively, all P<0.01]. The top 10 most frequently mutated genes in MMR-d EC were PTEN (85.5%, 47/55), ARID1A (80.0%, 44/55), PIK3CA (69.1%, 38/55), KMT2B (60.0%, 33/55), CTCF (45.5%, 25/55), RNF43 (40.0%, 22/55), KRAS (36.4%, 20/55), CREBBP (34.5%, 19/55), LRP1B (32.7%, 18/55) and BRCA2 (32.7%, 18/55). Concurrent PTEN, ARID1A and PIK3CA gene mutations were found in 50.9% (28/55) of MMR-d EC patients. Conclusions: The concordance of MMR-IHC and MSI-NGS in EC is relatively high.The discordance in a few MMR-d EC are mostly found in cases with MLH1 and (or) PMS2 protein loss or MMR protein subclonal staining caused by MLH1 gene promoter hypermethylation. In order to provide accurate molecular typing for EC patients, MLH1 gene methylation, MSI-PCR, MMR gene germline mutation and TMB should be combined to comprehensively evaluate MMR and MSI status.

[Correlation between pulmonary quantitative CT measurement indicators and respiratory symptoms in patients with chronic obstructive pulmonary disease in stable stage]

Objective: To explore the correlation between pulmonary quantitative CT measurement indicators and respiratory symptoms in patients with stable chronic obstructive pulmonary disease (COPD). Methods: A total of 186 patients with COPD in stable stage who visited in the outpatient department of Beijing Hospital from March 2021 to February 2022 were prospectively included. Demographic data, respiratory symptoms and lung function were collected. The original DICOM data of high-resolution CT (HRCT) were processed using the FACT medical imaging information system and the pulmonary emphysema index pixel index-950 (PI-950) and the airway wall thickness (4-6 T) and the percentage of airway area (4-6 WA%) of the 4-6 generation bronchi which represent the segmental and subsegmental bronchi were measured automatically. According to the modified British medical research council dyspnea scale (mMRC, 0-1 point for low score group, 2-4 points for high score group), chronic obstructive pulmonary disease assessment test (CAT, score<10 points for low score group,≥10 points for high score group), cough, expectoration and wheezing (asymptomatic group and symptomatic group), they were divided into two groups as dependent variables. The relationship between imaging parameters and the above symptoms was evaluated using a logistic regression model. Results: The study ultimately included 186 patients who met the inclusion criteria, including 162 males and 24 females, aged (68.9±9.3) years old. There were 83 patients in the high mMRC group, 120 patients in the high CAT group, 146 patients in the cough group, 154 patients in the expectoration group, and 65 patients in the wheezing group. The age and emphysema parameter PI-950 in the high score group of mMRC were higher than those in the low score group, while the percentage of the forced expiratory volume in 1 second (FEV1) predicted value (FEV1 pred) after medication, the percentage of carbon monoxide diffusion volume (DLCO) predicted value (DLCO pred), and the percentage of the maximum midexpiratory flow (MMEF) predicted value (MMEF pred) after medication were lower than those in the low score group (all P<0.05). The age of the high CAT group was higher than that of the low score group, while FEV1 pred and MMEF pred after medication were lower than those of the low score group (all P<0.05). The proportion of males, patients with smoking history, and smoking index in the cough group were higher than those in the non cough group, while the 4 WA% was lower than that in the non cough group (all P<0.05). The proportion of males, patients with smoking history, smoking index, and PI-950 in the expectoration group were higher than those in the non expectoration group, while FEV1 pred after medication and 4 WA% were lower than those in the non expectoration group (all P<0.05). The 5 WA% and 6 WA% of the wheezing group were higher than those of the non wheezing group, while MMEF pred after medication was lower than that of the non wheezing group (all P<0.05). Multivariate logistic regression analysis showed that after adjusting for demographic characteristics, smoking, combined diseases, lung function and other confounding factors, for every 10% increase in PI-950, the likelihood of developing more severe dyspnea for the patients (high score group according to mMRC) increased by 67.3% (OR=1.673, 95%CI: 1.052-2.658); Every 10% increase in 6WA% increased the likelihood of wheezing by 3.189 times (OR=4.189, 95%CI: 1.070-16.395). No correlation was found between various imaging indicators and cough, expectoration, and CAT scores (P>0.05). Conclusion: Quantitative CT measurement indicators in stable COPD patients can explain the presence and severity of respiratory symptoms, the pulmonary emphysema indicator is associated with dyspnea, and the percentage of proximal airway wall area is associated with wheezing.

Isolated neural arch tuberculosis with tuberculomas: case report

We reported a case of atypical spinal tuberculosis on the posterior elements of lumbar spine in a 52-year-old female. It was easy to be misdiagnosed as spinal tumor due to its imaging characteristics. We performed puncture biopsy to initially consider tuberculosis, and then the patient was accepted surgical treatment. The intraoperative removed specimen was sent to pathological examination, microbial culture, Xpert MTB/RIF and metagenomic next-generation sequencing (mNGS) and then the diagnosis of neural arch tuberculosis was confirmed. After operation, the patient obtained stable effect by anti-tuberculosis drug treatment. In a word, the uncommon case had an important reference significance for the diagnosis of atypical spine tuberculosis and differentiation from spinal tumors. It is critical to make right preliminary diagnosis by appropriate examination as it determined the next diagnosis and treatment in special and rare clinical cases.

[Continuous positive airway pressure therapy affects the recurrence of atrial fibrillation in patients with obstructive sleep apnea: a systematic review and meta-analysis]

Objective: A higher incidence of atrial fibrillation is associated with obstructive sleep apnea. The effects of continuous positive airway pressure on atrial fibrillation have been studied in observational studies and randomized controlled trials. We therefore conducted this meta-analysis to assess the effect of continuous positive airway pressure on the recurrence of atrial fibrillation after radiofrequency ablation. Methods: A comprehensive search was conducted in Pubmed, Embase, Cochrane, Web of Science, Wanfang Data and CNKI databases from inception to October 2022. We included cohort studies and randomized controlled trials containing atrial fibrillation situation after catheter ablation with and without continuous positive airway pressure therapy. The random effects model was used to assess odds ratios (OR) and confidence intervals (CI). I2 was used to assess the heterogeneity. Results: Eight studies with a total of 1 395 patients with obstructive sleep apnea met the inclusion criteria. Continuous positive airway pressure therapy decreased atrial fibrillation recurrence by 61% (OR=0.392, 95%CI: 0.267-0.576, I2=37.6%). Subgroup analysis showed that the protective effect was more significant in groups with more hypertension patients (OR=0.272 vs. 0.550, 95%CI: 0.165-0.449 vs. 0.329-0.922). Conclusions: Continuous positive airway pressure therapy reduces the recurrence rate of atrial fibrillation. Patients with hypertension are more likely to benefit from it.

[Prevalence of obesity and its association with dietary patterns: a cohort study among Tibetan pastoralists in Qinghai Province]

Objectives: To explore obesity prevalence and its association with dietary patterns among Tibetan pastoralists during the urbanization transition in Qinghai Province. Methods: Using an open cohort study design, 1 003 subjects were enrolled at baseline in 2018, 599 were followed up, and 1 012 were newly recruited in 2022. A total of 1 913 adults over 18 years were included in the study, and a questionnaire survey and health examination were conducted. Factor analysis was used to identify dietary patterns, and a mixed-effects model was used to analyze the association between dietary patterns and obesity. Results: From 2018 to 2022, the prevalence rates of overweight, obesity, and central obesity were 27.6%, 33.8%, and 54.6%, respectively. Age-sex-standardized prevalence of obesity and central obesity increased. Three dietary patterns were identified: the modern pattern was characterized by frequent consumption of pork, poultry, processed meat, fresh fruits, sugary drinks, salty snacks, etcetera; the urban pattern was characterized by frequent consumption of refined carbohydrates, beef and mutton, vegetables and eggs, etcetera; and pastoral pattern featured frequent consumption of tsamba, Tibetan cheese, buttered/milk tea, and whole-fat dairy products. After adjusting for demographic characteristics, socioeconomic status, and lifestyle factors, compared with the T1, subjects in the T3 of urban pattern scores were more likely to be overweight (OR=2.09, 95%CI: 1.10-3.95) and overweight/obese (OR=1.23, 95%CI: 1.00-1.51), whereas those in the T3 of pastoral pattern scores had a lower risk of overweight (OR=0.45, 95%CI: 0.24-0.84), obesity (OR=0.81, 95%CI: 0.69-0.95), overweight/obesity (OR=0.75, 95%CI: 0.61-0.91) and central obesity (OR=0.58, 95%CI: 0.38-0.89). Conclusions: Prevalence of obesity and central obesity was high among Tibetan pastoralists during the urbanization transition. Urban dietary pattern was a risk factor for overweight and overweight/obesity, whereas pastoral dietary pattern was a protective factor for overweight, obesity, overweight/obesity, and central obesity. Tailored interventions are needed to improve local people's health.

[Malignant gastrointestinal neuroectodermal tumor: a clinicopathological analysis of three cases]

Objective: To investigate the clinicopathological characteristics of malignant gastrointestinal neuroectodermal tumors (GNET), and to describe their clinical, histological, immunophenotypic, ultrastructural, and molecular features, diagnosis and differential diagnosis. Methods: Three cases of malignant GNET were collected at Xijing Hospital of the Fourth Military Medical University, from 2013 to 2022. All patients underwent surgical resection of the tumor. Histological, immunohistochemical (IHC), ultrastructural and molecular genetic analyses were performed, and the patients were followed up for six months, three years and five years. Results: There were two males and one female patients. The tumors were located in the ileum, descending colon, and rectum, respectively. Grossly, the tumors were solid, firm, and poorly circumscribed, measured in size from 2 to 4 cm in greatest dimension, and had a greyish-white cut surface. These tumors were histologically characterized by a sheet-like or nested population of oval to spindled cells or epithelioid cells with weakly eosinophilic or clear cytoplasm, small nucleoli and scattered mitoses. Electron microscopy showed neuroendocrine differentiation, and no evidence of melanogenesis. IHC staining showed that the tumor cells were diffusely positive for S-100 protein, SOX10, CD56, synaptophysin and vimentin. They were negative for melanocytic markers, HMB45 and Melan A. All three cases showed split EWSR1 signals consistent with a chromosomal translocation involving EWSR1. Next-generation sequencing in one case confirmed the presence of EWSR1-ATF1 fusion. These patients were followed up for 6 months, 3 years and 5 years, respectively, and all of them developed possible lung or liver metastases, and one of them died of multiple pulmonary metastases. Conclusion: Malignant GNET has distinctive morphological, IHC, and molecular genetic features and it should be differentiated from other malignancies of the gastrointestinal tract, especially clear cell sarcoma and melanoma.

[Progress in minimally invasive surgery for adjacent segment disease after lumbar fusion]

Adjacent segment disease (ASDis) is a common complication of posterior lumbar spine fusion and often requires surgical treatment. In the treatment of ASDis, percutaneous spinal endoscopy can be used for simple decompression without removal of the original internal fixation, or for posterior fixation and fusion under the scope or in combination with other access fixation and fusion techniques, with the advantages of less surgical trauma, less bleeding, and faster postoperative recovery. Traditional trajectory screw technique is one of the risk factors for adjacent segment degeneration because of its tendency to cause damage to the adjacent synovial joint during surgery. In contrast, the cortical tone trajectory (CBT) screw placement technique not only reduces the damage to the articular joint during the screw placement process, but also preserves the original internal fixation in the treatment of ASDis, which significantly reduces the surgical trauma. Secondly, the implantation of CBT screws with the aid of digital technologies such as three-dimentinal printed guides, CT navigation, and robotics allows for more precise "double nailing" of ASDis patients to complete the fusion of adjacent segments, and is a minimally invasive procedure to be considered for patients who meet the clinical indications for fusion. This article reviews the literature on the use of percutaneous spinal endoscopy and CBT in the surgical management of ASDis.

Establishment and characterization of an immortalized bovine intestinal epithelial cell line

Primary bovine intestinal epithelial cells (PBIECs) are an important model for studying the molecular and pathogenic mechanisms of diseases affecting the bovine intestine. It is difficult to obtain and grow PBIECs stably, and their short lifespan greatly limits their application. Therefore, the purpose of this study was to create a cell line for exploring the mechanisms of pathogen infection in bovine intestinal epithelial cells in vitro. We isolated and cultured PBIECs and established an immortalized BIEC line by transfecting PBIECs with the pCI-neo-hTERT (human telomerase reverse transcriptase) recombinant plasmid. The immortalized cell line (BIECs-21) retained structure and function similar to that of the PBIECs. The marker proteins characteristic of epithelial cells, cytokeratin 18 (CK18), occludin, zonula occludens protein 1 (ZO-1), E-cadherin and enterokinase, were all positive in the immortalized cell line, and the cell structure, growth rate, karyotype, serum dependence and contact inhibition were normal. The hTERT gene was successfully transferred into BIECs-21 where it remained stable and was highly expressed. The transport of short-chain fatty acids and glucose uptake by the BIECs-21 was consistent with PBIECs, and we showed that they could be infected with the intestinal parasite, Neospora caninum. The immortalized BIECs-21, which have exceeded 80 passages, were structurally and functionally similar to the primary BIECs and thus provide a valuable research tool for investigating the mechanism of pathogen infection of the bovine intestinal epithelium in vitro.

[Predictive value of stress-induced hyperglycemia on 28 d risk of all-cause death in intensive care patients]

OBJECTIVE

To investigate the relationship between stress glucose elevation and the risk of 28 d all-cause mortality in intensive care unit (ICU) patients, and to compare the predictive efficacy of different stress glucose elevation indicators.

METHODS

ICU patients who met the inclusion and exclusion criteria in the Medical Information Mart for Intensive Care Ⅳ (MIMIC-Ⅳ) database were used as the study subjects, and the stress glucose elevation indicators were divided into Q1 (0-25%), Q2 (>25%- 75%), and Q3 (>75%-100%) groups, with whether death occurred in the ICU and the duration of treatment in the ICU as outcome variables, and demographic characteristics, laboratory indicators, and comorbidities as covariates, Cox regression and restricted cubic splines were used to explore the association between stress glucose elevation and the risk of 28 d all-cause death in ICU patients; and subject work characteristics [receiver operating characteristic (ROC) and the area under curve (AUC)] were used to evaluate the predictive efficacy of different stress glucose elevation indicators, The stress hyperglycemia indexes included: stress hyperglycemia ratio (SHR1, SHR2), glucose gap (GG); and the stress hyperglycemia index was further incorporated into the Oxford acute severity of illness score (OASIS) to investigate the predictive efficacy of the improved scores: the AUC was used to assess the score discrimination, and the larger the AUC indicated, the better score discrimination. The Brier score was used to evaluate the calibration of the score, and a smaller Brier score indicated a better calibration of the score.

RESULTS

A total of 5 249 ICU patients were included, of whom 7.56% occurred in ICU death. Cox regression analysis after adjusting for confounders showed that the HR (95%CI) for 28 d all-cause mortality in the ICU patients was 1.545 (1.077-2.217), 1.602 (1.142-2.249) and 1.442 (1.001-2.061) for the highest group Q3 compared with the lowest group Q1 for SHR1, SHR2 and GG, respectively, and The risk of death in the ICU patients increased progressively with increasing indicators of stressful blood glucose elevation (P_trend < 0.05). Restricted cubic spline analysis showed a linear relationship between SHR and the 28 d all-cause mortality risk (P>0.05). the AUC of SHR2 and GG was significantly higher than that of SHR1: AUC_SHR2=0.691 (95%CI: 0.661-0.720), AUC_GG=0.685 (95%CI: 0.655-0.714), and AUC_SHR1=0.680 (95%CI: 0.650-0.709), P < 0.05. The inclusion of SHR2 in the OASIS scores significantly improved the discrimination and calibration of the scores: AUC_OASIS=0.820 (95%CI: 0.791-0.848), AUC_OASIS+SHR2=0.832 (95%CI: 0.804-0.859), P < 0.05; Brier score_OASIS=0.071, Brier score_OASIS+SHR2=0.069.

CONCLUSION

Stressful glucose elevation is strongly associated with 28 d all-cause mortality risk in ICU patients and may inform clinical management and decision making in intensive care patients.

A single-domain green fluorescent protein catenane

Natural proteins exhibit rich structural diversity based on the folds of an invariably linear chain. Macromolecular catenanes that cooperatively fold into a single domain do not belong to the current protein universe, and their design and synthesis open new territories in chemistry. Here, we report the design, synthesis, and properties of a single-domain green fluorescent protein catenane via rewiring the connectivity of GFP's secondary motifs. The synthesis could be achieved in two steps via a pseudorotaxane intermediate or directly via expression in cellulo. Various proteins-of-interest may be inserted at the loop regions to give fusion protein catenanes where the two subunits exhibit enhanced thermal resilience, thermal stability, and mechanical stability due to strong conformational coupling. The strategy can be applied to other proteins with similar fold, giving rise to a family of single-domain fluorescent proteins. The results imply that there may be multiple protein topological variants with desirable functional traits beyond their corresponding linear protein counterparts, which are now made accessible and fully open for exploration.

[Fumarate hydratase deficient uterine leiomyoma: a clinicopathological and molecular analysis of 80 cases]

Objective: To investigate the clinicopathologic and molecular characteristics of fumarate hydratase (FH) deficient uterine leiomyoma. Methods: Eighty cases of FH deficient uterine leiomyoma were diagnosed from April 2018 to September 2022 in Department of Pathology, Peking University Third Hospital. Sanger sequencing of FH gene exons (exon 1-10) were performed on tumor tissues and matched non-tumor tissues/peripheral blood for all cases. FH immunohistochemistry were performed in 74 cases; S-(2-succino)-cysteine (2SC) were also detected by immunohistochemistry in five cases. Results: Patients' age ranged from 18 to 54 (36.0±7.5) years, with more than 60% exhibiting clinical symptoms of multiple and large leiomyomas (the median diameter was 70 mm). More than four histologic features, including staghorn vasculature, alveolar-pattern edema, bizarre nuclei, oval nuclei arranged in chains, prominent eosinophilic nucleoli with perinucleolar haloes and eosinophilic intracytoplasmic globules were observed in 98.5% (67/68) patients. The immunohistochemical sensitivity of FH and 2SC were 97.3% and 100%, respectively. Based on the Sanger sequencing results, the cases were divided into germline variant group (31 cases), somatic variant group (29 cases) and no variant group (20 cases). Sixty-nine percent (20/29) of the patients with FH germline variation had clear family history. Conclusions: Clinical features, histological morphology, FH and 2SC immunohistochemistry and Sanger sequencing have their own significance and limitations in differential diagnosis of FH deficient uterine leiomyoma. In clinical practice, the above information should be fully integrated and studied for accurate pathologic diagnosis and selection of patients with FH germline variation.

Targeting PI3Kα overcomes resistance to KRasG12C inhibitors mediated by activation of EGFR and/or IGF1R

Although several KRasG12C inhibitors have displayed promising efficacy in clinical settings, acquired resistance developed rapidly and circumvented the activity of KRasG12C inhibitors. To explore the mechanism rendering acquired resistance to KRasG12C inhibitors, we established a series of KRASG12C-mutant cells with acquired resistance to AMG510. We found that differential activation of receptor tyrosine kinases (RTKs) especially EGFR or IGF1R rendered resistance to AMG510 in different cellular contexts by maintaining the activation of MAPK and PI3K signaling. Simultaneous inhibition of EGFR and IGF1R restored sensitivity to AMG510 in resistant cells. PI3K integrates signals from multiple RTKs and the level of phosphorylated AKT was revealed to negatively correlate with the anti-proliferative activity of AMG510 in KRASG12C-mutant cells. Concurrently treatment of a novel PI3Kα inhibitor CYH33 with AMG510 exhibited a synergistic effect against parental and resistant KRASG12C-mutant cells in vitro and in vivo, which was accompanied with concomitant inhibition of AKT and MAPK signaling. Taken together, these findings revealed the potential mechanism rendering acquired resistance to KRasG12C inhibitors and provided a mechanistic rationale to combine PI3Kα inhibitors with KRasG12C inhibitors for therapy of KRASG12C-mutant cancers in future clinical trials.

[Activation of JAK/STAT in ovarian high-grade serous cancers and its prognostic significance]

OBJECTIVE

The activation of Janus kinase (JAK) and signal transducers and activators of transcription (STAT) plays an important role in the prognosis and targeted therapy of ovarian high-grade serous carcinoma (HGSC). Utilizing simple and practicable technique, this study aimed to evaluate the activation of JAK/STAT signaling pathway in ovarian HGSC patients, and investigated the correlation between the activation of JAK/STAT signaling pathway and the prognosis of the HGSC patients.

METHODS

We performed immunohistochemistry of phosphorylated STAT3 (pSTAT3) and phosphorylated STAT5 (pSTAT5) on paraffin imbedded slides of 73 ovarian HGSC patients, and evaluated the expression level and range of both markers. According to the grading score of the immunostaining of pSTAT3 and pSTAT5, we divided the 73 ovarian HGSC cases into STAT3 low/high expression and STAT5 low/high expression groups, and analyzed the prognosis of the patients in different groups, in order to explore the relationship between the expression of pSTAT3 and pSTAT5 proteins and the prognosis of the HGSC patients.

RESULTS

Some of the ovarian HGSC cases showed high expression of pSTAT3 and pSTAT5 protein level, which was related to the poorer prognosis of the HGSC patients. There was a significant difference in the expression level of pSTAT3 and pSTAT5 between the patients with better prognosis (survival time ≥3 years) and poorer prognosis (survival time < 3 years). The patients with higher protein expression of pSTAT3, pSTAT5 or both markers might have poorer prognosis, with significant shorter progression-free survival time and overall survival time (P < 0.001).

CONCLUSION

Immunostaining of pSTAT3 and pSTAT5 proteins might be helpful to evaluate and predict the prognosis of the ovarian HGSC patients, and to identify the patients who might have higher chances to respond to the STAT inhibitors and anti-angiogenesis therapy.

Role of TPEN in Amyloid-β25-35-Induced Neuronal Damage Correlating with Recovery of Intracellular Zn2+ and Intracellular Ca2+ Overloading

The overproduction of neurotoxic amyloid-β (Aβ) peptides in the brain is a hallmark of Alzheimer's disease (AD). To determine the role of intracellular zinc ion (_iZn²⁺) dysregulation in mediating Aβ-related neurotoxicity, this study aimed to investigate whether N, N, N', N'‑tetrakis (2‑pyridylmethyl) ethylenediamine (TPEN), a Zn²⁺‑specific chelator, could attenuate Aβ_25-35‑induced neurotoxicity and the underlying mechanism. We used the 3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay to measure the viability of primary hippocampal neurons. We also determined intracellular Zn²⁺ and Ca²⁺ concentrations, mitochondrial and lysosomal functions, and intracellular reactive oxygen species (ROS) content in hippocampal neurons using live-cell confocal imaging. We detected L-type voltage-gated calcium channel currents (L-I_Ca) in hippocampal neurons using the whole‑cell patch‑clamp technique. Furthermore, we measured the mRNA expression levels of proteins related to the _iZn²⁺ buffer system (ZnT-3, MT-3) and voltage-gated calcium channels (Cav1.2, Cav1.3) in hippocampal neurons using RT-PCR. The results showed that TPEN attenuated Aβ_25-35‑induced neuronal death, relieved the Aβ_25-35‑induced increase in intracellular Zn²⁺ and Ca²⁺ concentrations; reversed the Aβ_25-35‑induced increase in ROS content, the Aβ_25-35‑induced increase in the L-I_Ca peak amplitude at different membrane potentials, the Aβ_25-35‑induced the dysfunction of the mitochondria and lysosomes, and the Aβ_25-35‑induced decrease in ZnT-3 and MT-3 mRNA expressions; and increased the Cav1.2 mRNA expression in the hippocampal neurons. These results suggest that TPEN, the Zn²⁺-specific chelator, attenuated Aβ_25-35‑induced neuronal damage, correlating with the recovery of intracellular Zn²⁺ and modulation of abnormal Ca²⁺-related signaling pathways.

Injectable Temperature-Sensitive Hydrogel Loaded with IL-36Ra for the Relief of Osteoarthritis

Osteoarthritis (OA) is an inflammatory disease accompanied by synovial joint inflammation, and IL-36 plays an important role in this process. Local application of IL-36 receptor antagonist (IL-36Ra) can effectively control the inflammatory response, thereby protecting cartilage and slowing down the development of OA. However, its application is limited by the fact that it is rapidly metabolized locally. We designed and prepared a temperature-sensitive poly(lactic-co-glycolic acid)-poly(ethylene glycol)-poly(lactic-co-glycolic acid) (PLGA-PEG-PLGA) hydrogel (IL-36Ra@Gel) system carrying IL-36Ra and evaluated its basic physicochemical characteristics. The drug release curve of IL-36Ra@Gel indicated that this system could slowly release the drug over a longer period. Furthermore, degradation experiments showed that it could be largely degraded from the body within 1 month. The biocompatibility-related results showed that it had no significant effect on cell proliferation compared to the control group. In addition, the expression of MMP-13 and ADAMTS-5 was lower in IL-36Ra@Gel-treated chondrocytes than in the control group, and the opposite results appeared in aggrecan and collagen X. After 8 weeks of treatment with IL-36Ra@Gel by joint cavity injection, HE and Safranin O/Fast green staining showed that the degree of cartilage tissue destruction in the IL-36Ra@Gel-treated group was less than those in other groups. Meanwhile, the joints of mice in the IL-36Ra@Gel group had the most intact cartilage surface, the smallest thickness of cartilage erosion, and the lowest OARSI and Mankins score among all groups. Consequently, the combination of IL-36Ra and PLGA-PLEG-PLGA temperature-sensitive hydrogels can greatly improve the therapeutic effect and prolong the drug duration time, thus effectively delaying the progression of degenerative changes in OA, providing a new feasible nonsurgical treatment for OA.

[Correlation between polycyclic aromatic hydrocarbons component phenanthrene and clinical indicators in patients on peritoneal dialysis]

Objective: To explore the correlation between polycyclic aromatic hydrocarbons (PAHs) component phenanthrene and clinical indicators in patients on continuous ambulatory peritoneal dialysis (CAPD). Methods: A total of 22 patients who underwent peritoneal dialysis catheterization and regular dialysis in the First Affiliated Hospital of Zhengzhou University from June to August 2018 were selected. Meanwhile, 18 healthy adults who underwent physical examination were also selected as the control group. Fasting blood samples were taken to detect the concentration of PAHs components for comparison, and the correlation between PAHs components and clinical indicators was further analyzed. Results: There were 22 cases in CAPD group (13 males and 9 females), and aged (45±13) years, while there were 18 cases in control group (6 males and 12 females), and aged (41±13) years. The concentration of blood phenanthrene (PHE) was the highest in CAPD group [0.449 (0.254, 0.581) mg/L], and it was only lower than acenaphthene in the control group [0.081 (0.050, 0.444) mg/L], with a statistically significant difference between the two groups (P=0.008). The analysis of PHE and clinical indicators showed that the concentration of PHE in CAPD patients was negatively correlated with weekly urea clearance index (Kt/V), weekly creatinine clearance (Ccr) and leukocyte level, but positively correlated with triglyceride level (r=-0.743, -0.749, -0.655 and 0.610, respectively, all P<0.05). Simple linear regression analysis demonstrated that for every 0.1 mg/L increase in PHE concentration, weekly Kt/V, weekly Ccr and white blood cell count decreased by 0.226, 3.050 L/1.73 m² and 0.512×10⁹/L, respectively, but triglyceride level increased by 0.152 mmol/L (all P<0.05). Multiple linear regression analysis revealed that the blood PHE concentration of CAPD patients was negatively correlated with weekly Kt/V and Ccr levels (t=-2.402 and -2.368, respectively, both P<0.05). All CAPD patients were followed up for 3 years, during which 8 patients (36.4%) withdrew from peritoneal dialysis due to technical failure, and the baseline PHE concentration was higher than that of patients who did not quit peritoneal dialysis [0.572 (0.416, 0.662) vs 0.268 (0.120, 0.475) mg/L, P=0.003]. Eight patients (36.4%) had cardiovascular events, and the baseline blood PHE concentration was higher than that of patients without cardiovascular events [0.542 (0.389, 0.741) vs 0.373 (0.157, 0.545) mg/L, P=0.045]. Conclusion: PHE correlates with clinical indicators of CAPD patients, including Kt/v, Ccr, leukocyte and triglyceride.

[Reclassification of flat type sudden deafness]

Objective: To reclassify the flat type sudden deafness according to the types of audiogram shape, and to explore the correlation between different pattern of hearing loss and prognosis. Methods: All of 1 024 patients with unilateral sudden deafness (492 males and 532 females, aged from 19 to 65 years, with an average age of 41.2 years old) admitted to 33 hospitals nationwide from August 2007 to October 2011 were divided into four types according to Chinese Guideline of Sudden Deafness(2015): low-frequency, high-frequency, flat and total deafness. Then, 402 patients with flat type sudden deafness were further divided into ascending type, descending type and consistent type according to the audiogram shapes. First, we compared the clinical characteristics and prognosis among these three subtypes of flat deafness, then compared the clinical characteristics and prognosis between ascending flat deafness and low-frequency deafness, descending flat deafness and high-frequency deafness, consistent flat deafness and total deafness, explored the factors related to the prognosis of flat deafness. SPSS 21.0 software, ANOVA, χ² test, t-test and Logistic regression were used to analyze the data. Results: The cure rates of flat ascending, flat descending and flat consistent sudden deafness groups were 70.7%, 17.1% and 34.0% respectively, with a statistically significant difference (χ²=33.984, P<0.001); However, there was no significant difference in age, sex and affected side (all P>0.05). The independent related factors for the recovery of flat type sudden deafness were as follows: whether there was dizziness [OR=0.459; 95% confidence interval (CI): 0.271-0.777], the type of audiogram shape (OR=0.721; 95%CI: 0.530-0.981), and days from onset to therapy (OR=0.903, 95%CI: 0.835-0.978), all of which had P values<0.05. There was no significant difference in the cure rates between ascending flat sudden deafness and low-frequency descending sudden deafness, descending flat sudden deafness and high-frequency descending sudden deafness (all P>0.05). The pure tone average(PTA) of flat consistent sudden deafness and total deafness were (69.1±18.9) and (101.7±17.7) dB HL, respectively, with a statistically significant difference (t=20.890, P<0.001), and the cure rates were 34.0% and 14.5%, respectively, with a statistically significant difference (χ²=29.012, P<0.001). Conclusion: According to the audiogram shape, the flat type sudden deafness can be further divided into ascending flat sudden deafness, descending flat sudden deafness and consistent flat sudden deafness, which can more effectively evaluate the prognosis. The cure rate of ascending flat sudden deafness is similar to that of low-frequency sudden deafness, and the prognosis is well; The cure rate of descending flat sudden deafness is similar to that of high-frequency descending sudden deafness, and the prognosis is poor. The cure rate of consistent flat sudden deafness is higher than that of total deafness. PTA plays an important role in the prognosis of consistent flat sudden deafness and total deafness. Total deafness can be regarded as a single type of sudden deafness.

Chest computed tomography analysis of lung sparing morphology: differentiation of COVID-19 pneumonia from influenza pneumonia and bacterial pneumonia using the arched bridge and vacuole signs

INTRODUCTION

This study evaluated the arched bridge and vacuole signs, which constitute morphological patterns of lung sparing in coronavirus disease 2019 (COVID-19), then examined whether these signs could be used to differentiate COVID-19 pneumonia from influenza pneumonia or bacterial pneumonia.

METHODS

In total, 187 patients were included: 66 patients with COVID-19 pneumonia, 50 patients with influenza pneumonia and positive computed tomography findings, and 71 patients with bacterial pneumonia and positive computed tomography findings. Images were independently reviewed by two radiologists. The incidences of the arched bridge sign and/or vacuole sign were compared among the COVID-19 pneumonia, influenza pneumonia, and bacterial pneumonia groups.

RESULTS

The arched bridge sign was much more common among patients with COVID-19 pneumonia (42/66, 63.6%) than among patients with influenza pneumonia (4/50, 8.0%; P<0.001) or bacterial pneumonia (4/71, 5.6%; P<0.001). The vacuole sign was also much more common among patients with COVID-19 pneumonia (14/66, 21.2%) than among patients with influenza pneumonia (1/50, 2.0%; P=0.005) or bacterial pneumonia (1/71, 1.4%; P<0.001). The signs occurred together in 11 (16.7%) patients with COVID-19 pneumonia, but they did not occur together in patients with influenza pneumonia or bacterial pneumonia. The arched bridge and vacuole signs predicted COVID-19 pneumonia with respective specificities of 93.4% and 98.4%.

CONCLUSION

The arched bridge and vacuole signs are much more common in patients with COVID-19 pneumonia and can help differentiate COVID-19 pneumonia from influenza and bacterial pneumonia.

Xanthine dehydrogenase rewires metabolism and the survival of nutrient deprived lung adenocarcinoma cells by facilitating UPR and autophagic degradation

Xanthine dehydrogenase (XDH) is the rate-limiting enzyme in purine catabolism by converting hypoxanthine to xanthine and xanthine to uric acid. The altered expression and activity of XDH are associated with the development and prognosis of multiple types of cancer, while its role in lung adenocarcinoma (LUAD) remains unknown. Herein, we demonstrated that XDH was highly expressed in LUAD and was significantly correlated with poor prognosis. Though inhibition of XDH displayed moderate effect on the viability of LUAD cells cultured in the complete medium, it significantly attenuated the survival of starved cells. Similar results were obtained in XDH-knockout cells. Nucleosides supplementation rescued the survival of starved LUAD cells upon XDH inhibition, while inhibition of purine nucleoside phosphorylase abrogated the process, indicating that nucleoside degradation is required for the XDH-mediated survival of LUAD cells. Accordingly, metabolic flux revealed that ribose derived from nucleoside fueled key carbon metabolic pathways to sustain the survival of starved LUAD cells. Mechanistically, down-regulation of XDH suppressed unfolded protein response (UPR) and autophagic flux in starved LUAD cells. Inhibition of XDH decreased the level of amino acids produced by autophagic degradation, which was accompanied with down-regulation of mTORC1 signaling. Supplementation of amino acids including glutamine or glutamate rescued the survival of starved LUAD cells upon knockout or inhibition of XDH. Finally, XDH inhibitors potentiated the anti-cancer activity of 2-deoxy-D-glucose that induced UPR and/or autophagy in vitro and in vivo. In summary, XDH plays a crucial role in the survival of starved LUAD cells and targeting XDH may improve the efficacy of drugs that induce UPR and autophagy in the therapy of LUAD.

Insulin Resistance-Varying Associations of Adiposity Indices with Cerebral Perfusion in Older Adults: A Population-Based Study

OBJECTIVES

Excessive accumulation of adipose tissue may accelerate brain aging, but the underlying mechanisms are poorly understood. Several adiposity indices were proposed to assess obesity, while their linkage with brain health in older adults remained unclear. Here we aimed to examine the associations of adiposity indices with global and regional cerebral blood flow (CBF) in older adults, while considering insulin resistance.

DESIGN

This was a cross-sectional population-based study that included older adults derived from the baseline participants in the ongoing Multimodal Interventions to Delay Dementia and Disability in rural China (MIND-China) study.

SETTING AND PARTICIPANTS

The study included 103 Chinese rural-dwelling older adults (age≥60 years; 69.9% women) who underwent brain magnetic resonance imaging scans.

METHODS

We estimated eight adiposity indices based on anthropometric measures. We automatically quantified global and regional CBF using the arterial spin labeling scans. Insulin resistance was assessed using the triglyceride-glucose index and then dichotomized into high and low levels according to the median. Data were analyzed using general linear model and voxel-wise analysis.

RESULTS

Of the eight examined adiposity indices, only higher waist-to-height ratio (WHtR) and body roundness index (BRI) were associated with reduced global CBF (multivariable-adjusted β-coefficients and 95%CI: -1.76; -3.25, -0.27 and -1.77; -3.25, -0.30, respectively) and hypoperfusion in bilateral middle temporal gyri, angular gyri and superior temporal gyri, left middle cingulum and precuneus (P<0.05). There were statistical interactions of WHtR and BRI with levels of insulin resistance on CBF, such that the significant associations of higher WHtR and BRI with lower global and regional CBF existed only in people with high insulin resistance (P<0.05).

CONCLUSION

Higher WHtR and BRI are associated with cerebral hypoperfusion in older adults, especially in people with high insulin resistance. This may highlight the pathological role of visceral fat in vascular brain aging.

[The peripheral blood inflammatory markers in Ménière's disease patients with and without migraine]

Objective: To investigate the peripheral blood inflammatory markers including white blood cell count (WBC), monocytes, neutrophils, lymphocytes, platelets, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), high-density lipoprotein(HDL-C), low-density lipoprotein and fibrinogen (FIB) in Ménière's disease (MD) patients with and without migraine, and to explore the relationship between the inflammatory response with MD and migraine. Methods: The general physical condition, clinical manifestations, pure-tone audiometry, and peripheral blood inflammatory markers of 92 unilateral MD patients who were hospitalized in Peking University People's Hospital for surgical treatment from January 2017 to January 2021 were continuously collected. Meanwhile, 50 healthy controls matched with age and sex were included, and their general physical conditions and peripheral blood inflammatory markers were also collected. This study consisted of two parts. First, the differences in epidemical characteristics and peripheral blood inflammatory markers between MD patients and healthy controls were compared by univariate analysis. Second, all 92 MD patients were divided into two subgroups according to whether they were accompanied by migraine. The clinical characteristics and peripheral blood inflammatory markers of MD patients with and without migraine were compared by univariate analysis. Thereafter, binary Logistic regression was used to analyze the related factors of whether MD patients were accompanied with migraine. Results: Compared with the healthy control group, the peripheral blood WBC, neutrophils and FIB of MD patients were significantly increased (all P<0.05). Compared with MD patients without migraine, MD patients with migraine had higher female prevalence, longer disease history, lower low-frequency hearing threshold, higher frequency of vertigo attacks and higher HDL-C levels (all P<0.05), meanwhile, female, frequency of vestibular attacks and HDL-C were independent related factors of whether MD patients were accompanied with migraine. Conclusion: The occurrence of MD and migraine may be related to the inflammatory response. The level of anti-inflammatory factors in the blood of MD patients with migraine are higher, suggesting that the inflammatory response status of MD patients with and without migraine is different.

Disrupted microbiota-barrier-immune interaction in phthalates-mediated barrier defect in the duodenum

As one of the most used phthalates, Di (2-ethylhexyl) phthalate (DEHP) is a widespread environmental contaminant. Extremely persistent plastic can enter the food chain of animals through the aquatic environment, affect metabolic pathways and cause damage to the digestive system. But the molecular mechanism of its toxic effects on the duodenum in birds has not been elucidated. To investigate the toxicity of phthalates in the duodenum, quails were gavaged with 250, 500, and 750 mg/kg doses of DEHP for 45 days, and water and oil control groups were retained. This study revealed that subchronic exposure to DEHP could lead to duodenal barrier defect in quail. The damage to duodenum was reflected in a reduction in V/C and tight junction proteins. Moreover, DEHP also led to a breakdown of antimicrobial defenses through the flora derangement, which acted as a biological barrier. The massive presence of Lipopolysaccharide (LPS) led to the activation of TLR4 receptors. In addition, DEHP activated oxidative stress, which synergized the inflammatory response induced by the TLR4-NFκB pathway, and further promoted duodenum damage. This study provides a base for the further effect of phthalates on the microbiota-barrier-immune interaction.

[Clinical application of laparoscopic sentinel lymph node mapping in early staged cervical cancer]

Objective: To investigate the application of sentinel lymph node biopsy (SLNB) in early-staged cervical cancer by laparoscopy. Methods: It was a prospective, single-arm, single-center clinical study. Seventy-eight cases of cervical cancer patients were collected from July 2015 to December 2018 at the Fourth Hospital of Hebei Medical University. All the patients were injected with tracer into the disease-free block of cervical tissue after anesthesia by the same surgeon who learned sentinel lymph node (SLN) mapping technique in Memorial Sloan-Kettering Cancer Center, and underwent SLN mapping followed by complete pelvic lymphadenectomy. Moreover, all the dissected lymph nodes were stained with hematoxylin eosin staining (HE) pathological examination. Besides, the negative SLN on hematoxylin-eosin staining were detected by immunohistochemistry cytokeratin staining micro-metastasis. To analyze the distribution, detection rate, false negative rate the sensitivity and negative predictive value of the SLN in early-staged cervical cancer by laparoscopy, and explore the value of SLN mapping in predicting the lymph nodes metastasis in early-staged cervical cancer. Results: The overall detection rate of SLN in cervical cancer was 99% (77/78), bilateral detection rate was 87% (68/78). The average of 12.4 lymph node (LN) and 3.6 SLN were dissected for each patients each side. SLN of cervical cancer were mainly distributed in the obturator space (61.5%, 343/558), followed by external iliac (23.5%, 131/558), common iliac (7.3%, 41/558), para-uterine (3.8%, 21/558), internal iliac (2.2%, 12/558), para abdominal aorta (1.1%, 6/558), and anterior sacral lymphatic drainage area (0.7%, 4/558). Fourteen cases of LN metastasis were found among all 78 cases. There were a total of 38 positive LN, including 26 SLN metastasis and 12 none sentinel LN metastasis. Through immunohistochemical staining and pathological ultra-staging, 1 SLN was found to be isolated tumor cells (ITC), and 5 SLNs were found to be micro-metastases (MIC), accounting for 23% (6/26) of positive SLN. SLN mapping with pathological ultra-staging improved the prediction of LN metastasis in cervical cancer (2/14). Metastatic SLN mainly distributed in the obturator space (65%, 17/26), peri-uterine region (12%, 3/26), common iliac region (15%, 4/26), and external iliac region (8%, 2/26). The consistency of the diagnosis of lymph node metastasis by SLN biopsy and postoperative retroperitoneal lymph node metastasis showed that the Kappa value was 1.000 (P<0.001), indicated that the metastasis status of SLN and retroperitoneal lymph node were completely consistent. The sensitivity, specificity, accuracy, false-negative rate, and negative predictive value of SLN biopsy in the diagnosis of lymph node metastasis were 100%, 100%, 100%, 0, and 100%, respectively. Conclusions: SLN in early-staged cervical cancer patients were mainly distributed in the obturator and external iliac space, pathalogical ultra-staging of SLN could improve the prediction of LN metastasis. Intraoperative SLN mapping is safe, feasible and could predict the state of retroperitoneal LN metastasis in early-staged cervical cancer. SLNB may replace systemic pelvic lymphadenectomy.

Constraints on Sub-GeV Dark Matter-Electron Scattering from the CDEX-10 Experiment

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4  kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80  MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90  MeV/c^{2} with heavy mediators and m_{χ} larger than 100  MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.

Exotic Dark Matter Search with the CDEX-10 Experiment at China's Jinping Underground Laboratory

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46}  cm^{2} (90% C.L.) at DM mass of 10  MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14  MeV/c^{2} for the massless dark photon and bound DM final state, respectively.

[Bedside monitoring of lung perfusion by electrical impedance tomography]

As a non-invasive and radiation-free bedside imaging method, electrical impedance tomography (EIT) can perform real-time regional pulmonary ventilation evaluation and pulmonary blood flow monitoring for patients, thus realizing bedside ventilation/perfusion matching visualization, effectively guiding the pathophysiological mechanism of hypoxemia, and providing a new method for the study of pulmonary blood flow. EIT has also played a unique and irreplaceable role in COVID-19 research and treatment. At the same time, as functional imaging, the operation details and image reconstruction algorithm of this technology still need to be further optimized by more researches to provide a more robust evaluation in clinical application. In this paper, EIT pulmonary blood flow monitoring methods, operation and implementation of monitoring indicators, application and related research progress will be described.

Strategy and Efficacy of Surgery for Congenital Cervicothoracic Scoliosis with or without Hemivertebra Osteotomy

OBJECTIVE

Cervicothoracic scoliosis will cause severe deformities in the early stage, and its structure is complex and the surgical methods are varied. The purpose of this research is to explore the indication and analyze the corrective effect of the two different posterior approach surgical strategies, including correction with fusion and hemivertebra osteotomy, for congenital cervicothoracic scoliosis deformities in children and adolescents.

METHODS

This was a retrospective study of 21 patients with cervicothoracic scoliosis who received surgical treatment from January 2010 to June 2020, including nine cases of posterior hemivertebra osteotomy and fusion surgery and 12 cases of posterior correction and fusion alone. The Cobb angle, T1 tilt angle, clavicular angle, neck tilt angle, radiographic shoulder height, sagittal vertical axis, coronal balance distance, and local kyphosis angle were measured preoperatively, postoperatively, and at the last follow-up. Posterior approach hemivertebra resection or correction with fusion surgery was adopted based on the different individual characteristics of deformity such as main curve Cobb angle, growth potential, and flexibility. Patients were divided into two groups (osteotomy group and nonosteotomy group) according to whether a hemivertebra osteotomy was performed, and the corrective results in the two groups were compared. Paired-sample t tests or independent-sample t tests were used.

RESULTS

The median follow-up after surgery of the 21 patients was 36 months (range, 18-72 months). The Cobb angle was corrected from 45.81° ± 14.23° preoperatively to 10.48° ± 5.56° postoperatively (correction rate, 77.78% ± 8.93%). The T1 tilt angle decreased from 15.26° ± 7.08° preoperatively to 3.33° ± 2.14° postoperatively (correction rate,73.42% ± 21.86%). The radiographic shoulder height was corrected from 1.13 ± 0.74 cm preoperatively to 0.52 ± 0.42 cm postoperatively (correction rate, 39.51% ± 35.65%). The clavicular angle improved from 2.52° ± 1.55° preoperatively to 1.16° ± 0.96° postoperatively (correction rate, 47.18% ± 35.84%). No significant differences were found at the last follow-up (p > 0.05). The Cobb angle of the main curve, T1 tilt angle, clavicular angle, cervical tilt angle, and shoulder height difference were similar in the two groups (p > 0.05).

CONCLUSIONS

Posterior approach hemivertebra resection or correction with fusion surgery can be used in the treatment of congenital cervicothoracic scoliosis with satisfactory results, and the surgeon can make an individualized surgical plan according to individual characteristics of deformity.

Posterior-only debridement, bone fusion, single-segment versus short-segment instrumentation for mono-segmental lumbar or lumbosacral pyogenic vertebral osteomyelitis: minimum five year follow-up outcomes

Background

Pyogenic vertebral osteomyelitis (PVO), which is a potentially life-threatening condition and is associated with significant morbidity and mortality, is a cause of back pain that can lead to neurologic deficits if not diagnosed in time and effectively treated. The objective of this study is to compare the efficacy of posterior single-segment and short-segment fixation combined with one-stage posterior debridement and fusion for the treatment of mono-segmental lumbar or lumbosacral PVO.

Methods

Charts of all patients with mono-segmental lumbar or lumbosacral PVO were treated by single-stage posterior debridement, bone graft fusion, and pedicle screw fixation from April 2012 to January 2016. All patients were divided into two groups: sinlge-segment fixation (Group A, n = 31) and short-segment fixation (Group B, n = 36). These patients were followed up for a minimum of five years. The clinical efficacy was evaluated and compared on average operation time, blood loss, visual analog scale (VAS), erythrocyte sedimentation rate (ESR), C-Reactive protein (CRP), neurological function recovery and local lordotic angle.

Results

All 67 patients were completely cured during the follow-up. All patients had significant improvement of neurological condition and pain relief at the final follow-up. The VAS was 7.1 ± 0.7 in group A and 7.2 ± 0.6 in group B pre-operatively, which decreased to 2.1 ± 0.6 and 2.0 ± 0.7, respectively, at three months after surgery, then reduced to 0.4 ± 0.5 and 0.5 ± 0.5, respectively, at the final follow-up. ESR, CRP returned to normal limits in all patients 3 months after surgery. The mean blood loss and operation time in group A were less than that in group B (P < 0.05). The local lordotic angle in group A was increased from preoperative − 1.7 ± 7.9° to postoperative 5.8 ± 7.1°, with angle loss of 1.5 ± 0.8° at the final follow-up, respectively (P < 0.05). The local lordotic angle in group B was increased from preoperative − 1.6 ± 7.8° to postoperative 13.5 ± 6.2°, with angle loss of 1.3 ± 0.8° at the final follow-up, respectively (P < 0.05). In the mean postoperative local lordotic angle, there was significant difference between the two groups at the time of immediate postoperative period or the final follow-up (P < 0.05).

Conclusion

Posterior-only debridement, interbody graft using titanium mesh cage, posterior single-segment instrumentation and fusion represent a safe and effective treatment option for selected patients with mono-segmental lumbar and lumbosacral PVO. This approach may preserve more lumbar normal motor units with less blood loss and operation time when compared with that of short-segment fixation. But short-segment fixation was superior to the single-segment fixation in the correction of kyphosis.

[Application of near infrared fluorescence imaging in detection of residual cancer in oral squamous cell carcinoma]

Objective: Local recurrence is the main cause of treatment failure in patients with oral squamous cell carcinoma (OSCC). This study was proposed to investigate the feasibility of near infrared fluorescence (NIF) via indocyanine green (ICG) for monitoring surgical marginal in operation for OSCC patients. Methods: In 35 patients with OSCC treated surgically in the Department of Oral and Maxillofacial Surgery, Nanjing University School of Medicine, from January 2019 to June 2020, ICG (0.75 mg/kg) was administered intravenously via elbow vein at (12±1) hours before surgery, and NIF was performed intraoperatively on the surgical field and the cut edge of the surgically excised specimen, and fluorescence intensity was measured for OSCC tissue and normal oral mucosa, abnormal fluorescence signals were taken and subjected to rapid cryopathological examination. Correlation between NIF tumor boundary grading and pathological tumor boundary grading was analyzed by Spearman correlation analysis. Results: Clear ICG NIF was obtained for tumor lesions in all 35 patients, with a positive rate of 100%. The fluorescence intensity of OSCC tissue was (412.73±146.56) au, which was higher than that of normal oral mucosa tissue [(279.38±82.56) au, P<0.01]. Abnormal fluorescence signals were detected at the tumor bed and the cut edge of the surgical resection specimen in 4 patients, of which 2 cases were pathologically confirmed as cancer cell residue and 2 cases as inflammatory cell infiltration. The rate of positive detection of cut margins using ICG NIF technique in OSCC was 5.7% (2/35). Twenty of the 35 OSCC patients had grade 1, 11 of grade 2, and 4 of grade 3 tumor borders revealed by NIF of surgical resection specimens, which was positively correlated with pathological tumor border (r=0.809, P<0.001). Conclusions: ICG NIF technique can effectively detect the residual cancer cells at the incision margin, which is of great clinical value in reducing local recurrence of OSCC after surgery due to intraoperative cancer residue.

[Research advances on exosomes derived from adipose-derived mesenchymal stem cells in promoting diabetic wound healing]

Impaired healing of diabetic wounds is mainly attributed to its pathological mechanism, and refractory diabetic wounds bring heavy burdens to patients and society. Exosomes derived from stem cells possess the similar ability as stem cells in promoting tissue regeneration and more clinical advantages and are gradually playing important roles in wound healing. In recent years, researches have shown that exosomes derived from adipose-derived mesenchymal stem cells (ADSC-EXOs) can promote the healing of diabetic wounds by participating in various processes of wound healing. This article reviews the pathological mechanism leading to impaired healing of diabetic wounds, the related mechanism and the application prospect of ADSC-EXOs in promoting diabetic wound healing.

Evaluation of individual and ensemble probabilistic forecasts of COVID-19 mortality in the United States

Short-term probabilistic forecasts of the trajectory of the COVID-19 pandemic in the United States have served as a visible and important communication channel between the scientific modeling community and both the general public and decision-makers. Forecasting models provide specific, quantitative, and evaluable predictions that inform short-term decisions such as healthcare staffing needs, school closures, and allocation of medical supplies. Starting in April 2020, the US COVID-19 Forecast Hub (https://covid19forecasthub.org/) collected, disseminated, and synthesized tens of millions of specific predictions from more than 90 different academic, industry, and independent research groups. A multimodel ensemble forecast that combined predictions from dozens of groups every week provided the most consistently accurate probabilistic forecasts of incident deaths due to COVID-19 at the state and national level from April 2020 through October 2021. The performance of 27 individual models that submitted complete forecasts of COVID-19 deaths consistently throughout this year showed high variability in forecast skill across time, geospatial units, and forecast horizons. Two-thirds of the models evaluated showed better accuracy than a naïve baseline model. Forecast accuracy degraded as models made predictions further into the future, with probabilistic error at a 20-wk horizon three to five times larger than when predicting at a 1-wk horizon. This project underscores the role that collaboration and active coordination between governmental public-health agencies, academic modeling teams, and industry partners can play in developing modern modeling capabilities to support local, state, and federal response to outbreaks.

[The prevalence and associated factors of metabolic syndrome among Tibetan pastoralists in transition from nomadic to settled urban environment]

Objective: To study the prevalence and associated factors of metabolic syndrome (MS) among Tibetan pastoralists in transition from high altitude nomadic to settled urbanized environment, especially dietary factors. Methods: The community-based cross-sectional study included 920 Tibetan adults (men 419, women 501). Data were collected using questionnaires, anthropometric measurements, and biomarker tests. Questionnaires included socio-economic, lifestyle characteristics and food consumption. Principal component analysis was used to identify dietary patterns. The risk factors of MS and its components were analyzed by logistic regression model. Results: The prevalence rates of MS and its components were 32.8% (MS), 83.7% (decreased HDL-C), 62.1% (central obesity), 36.7% (elevated blood pressure), 11.8% (elevated TG), and 7.9% (elevated blood glucose), respectively. The prevalence of overweight was 31.2%, obesity 30.3%. Multivariate analysis showed smoking was associated factor for both of decreased HDL-C (OR=1.239, 95%CI: 1.025-1.496) and elevated TG (OR=1.277, 95%CI: 1.038-1.571). Alcohol drinking appeared as associated factor of elevated TG (OR=1.426, 95%CI: 1.055-1.927). However, physical activity showed as a protective factor for central obesity, decreased HDL-C, and elevated TG. With the increase of age, the adherence to the urban and western dietary patterns decreased, and that to the pastoral dietary pattern increased. By quintiles of dietary pattern scores, the urban dietary pattern was significantly associated with MS (trend test P=0.016). Conclusions: Tibetan pastoralists had high prevalence of both MS and obesity. Smoking, alcohol drinking, the transition from pastoral dietary pattern to urban dietary pattern and inadequate physical activity served as associated factors for MS and its components.

[Preliminary study on centrifugation time of liquid plasmatrix for soft tissue regeneration]

Objective: To provide reference for clinical application of liquid plasmatrix, and to investigate the optimal centrifugation time of liquid plasmatrix prepared by horizontal centrifugation for soft tissue regeneration from the aspects of mechanical properties, biological properties, and the effect of promoting soft tissue regeneration. Methods: Venous blood was collected from 6 healthy volunteers [3 males and 3 females, aged (26±2) years, with informed consent] who volunteered to donate blood at School of Stomatology, Wuhan University from September to November 2021. The collected venous blood was centrifuged at 500 ×g for 3, 5, 8 and 12 min to obtain liquid plasmatrix. The volume, weight, solidification time, and mechanical properties of liquid plasmatrix prepared at different centrifugation time were measured and recorded (the sample size at each time point was 3). The microstructure of different groups of liquid plasmatrix clot was observed by scanning electron microscope (SEM). The rheological properties of each group of liquid plasmatrix clot were measured by rheological test. The number and concentration of cells in the whole blood group and in each liquid plasmatrix group were measured using complete blood count test. The distribution of cells in the liquid plasmatrix clots was observed by hematoxylin-eosin staining. The effect of control group (Dulbecco's modified Eagle's medium containing 20% fetal bovine serum) and liquid plasmatrix clot exudates in 3, 5, 8, 12 min group (the sample size at each time point was 3) on gingival fibroblast migration was detected by cell migration method. Finally, the effects of control group and liquid plasmatrix clot exudates on the morphology of gingival fibroblasts were observed by fluorescence microscope. Results: The volume of liquid plasmatrix in 3, 5, 8 and 12 min group were approximately (2.47±0.12), (2.67±0.12), (3.53±0.12) and (3.73±0.12) ml, respectively. The weight of liquid plasmatrix in 3, 5, 8 and 12 min group were approximately (0.35±0.01), (0.46±0.02), (0.88±0.06) and (1.03±0.01) g, respectively. The maximum tensile force of liquid plasmatrix clots in 3, 5, 8 and 12 min group were (0.55±0.03), (0.56±0.03), (1.31±0.05) and (1.38±0.02) N, respectively. SEM results showed that the fibers inside the liquid plasmatrix clot became denser with increased centrifugation time. Compared with other groups, the concentrations of leukocytes, neutrophils, monocytes and lymphocytes in 8 min group were the highest, and the distribution of cell was more even. Compared with other groups, the efficiency of stimulating gingival fibroblast migration in 8 min group was the best (1.60±0.01). Fluorescence staining test showed that the liquid plasmatrix clot exudates could make gingival fibroblasts more stretched compared with control group. Conclusions: The present study shows that liquid plasmatrix prepared by centrifugation with 500 ×g centrifugal force for 8 min has higher concentration of viable cells and the ability to promote the migration of gingival fibroblasts.

[The safety and efficacy of anlotinib in combination with stereotactic radiotherapy for the treatment of brain metastases from non-small cell lung cancer]

Objective: To investigate the efficacy and safety of anti-vascular drug anlotinib in combination with stereotactic radiosurgery (SRS) for the treatment of brain metastases from non-small cell lung cancer (NSCLC). Methods: A total of 46 patients diagnosed with NSCLC brain metastases and treated with SRS in Peking University Third Hospital were included from October 2017 to June 2019. Of these, 21 patients (33 lesions) received anlotinib combined with SRS (combined treatment group), while 25 patients (35 lesions) only received SRS (SRS-alone group). The data of combined treatment group and SRS-alone group were compared, including remission rate of intracranial hypertension, response rate (RR) of local control of intracranial lesions, incidence of radiation-induced brain necrosis and intracranial progression-free survival (iPFS). The medication and adverse reactions of anlotinib in the combined treatment group were recorded. Results: The remission rate of intracranial hypertension in the combined treatment group was 71.4% (15/21), which was significantly higher than that in the SRS-alone group [12.0% (3/25), P<0.001). However, the RR of combined treatment group and SRS-alone group was 80.9% (17/21) and 60.0% (15/25), respectively, with no statistically significant difference (P=0.289). The incidence of radiation-induced brain necrosis in the combined treatment group was 3.0% (1/33), which was significantly lower than that in the SRS-alone group [20.0% (7/35), P=0.030]. The iPFS of the combination treatment group was (13.9±2.4) months, which was significantly longer than that in the SRS-alone group [(11.4±1.8) months, P<0.001]. The medication time of anlotinib in the combined treatment group was 6 (6, 18) weeks. One patient developed grade Ⅰ hypertension and one patient developed grade Ⅰ hand-foot syndrome. The incidence of drug-related adverse reactions was 9.5% (2/21). Conclusions: Anlotinib in combination with SRS may relieve brain edema, reduce the rate of radiation-induced brain necrosis, and the rate of drug-related adverse reactions were low.