Experimental Limits on Solar Reflected Dark Matter with a New Approach on Accelerated-Dark-Matter-Electron Analysis in Semiconductors

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4  kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15  keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1  MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

[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.

[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.

[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.

[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.

Capturing heterogeneous conformers of cobalamin riboswitch by cryo-EM

RNA conformational heterogeneity often hampers its high-resolution structure determination, especially for large and flexible RNAs devoid of stabilizing proteins or ligands. The adenosylcobalamin riboswitch exhibits heterogeneous conformations under 1 mM Mg2+ concentration and ligand binding reduces conformational flexibility. Among all conformers, we determined one apo (5.3 Å) and four holo cryo-electron microscopy structures (overall 3.0-3.5 Å, binding pocket 2.9-3.2 Å). The holo dimers exhibit global motions of helical twisting and bending around the dimer interface. A backbone comparison of the apo and holo states reveals a large structural difference in the P6 extension position. The central strand of the binding pocket, junction 6/3, changes from an 'S'- to a 'U'-shaped conformation to accommodate ligand. Furthermore, the binding pocket can partially form under 1 mM Mg2+ and fully form under 10 mM Mg2+ within the bound-like structure in the absence of ligand. Our results not only demonstrate the stabilizing ligand-induced conformational changes in and around the binding pocket but may also provide further insight into the role of the P6 extension in ligand binding and selectivity.

Direct observation of tRNA-chaperoned folding of a dynamic mRNA ensemble

T-box riboswitches are multi-domain noncoding RNAs that surveil individual amino acid availabilities in most Gram-positive bacteria. T-boxes directly bind specific tRNAs, query their aminoacylation status to detect starvation, and feedback control the transcription or translation of downstream amino-acid metabolic genes. Most T-boxes rapidly recruit their cognate tRNA ligands through an intricate three-way stem I-stem II-tRNA interaction, whose establishment is not understood. Using single-molecule FRET, SAXS, and time-resolved fluorescence, we find that the free T-box RNA assumes a broad distribution of open, semi-open, and closed conformations that only slowly interconvert. tRNA directly binds all three conformers with distinct kinetics, triggers nearly instantaneous collapses of the open conformations, and returns the T-box RNA to their pre-binding conformations upon dissociation. This scissors-like dynamic behavior is enabled by a hinge-like pseudoknot domain which poises the T-box for rapid tRNA-induced domain closure. This study reveals tRNA-chaperoned folding of flexible, multi-domain mRNAs through a Venus flytrap-like mechanism.

[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.

Architectural basis for cylindrical self-assembly governing Plk4-mediated centriole duplication in human cells

Proper organization of intracellular assemblies is fundamental for efficient promotion of biochemical processes and optimal assembly functionality. Although advances in imaging technologies have shed light on how the centrosome is organized, how its constituent proteins are coherently architected to elicit downstream events remains poorly understood. Using multidisciplinary approaches, we showed that two long coiled-coil proteins, Cep63 and Cep152, form a heterotetrameric building block that undergoes a stepwise formation into higher molecular weight complexes, ultimately generating a cylindrical architecture around a centriole. Mutants defective in Cep63•Cep152 heterotetramer formation displayed crippled pericentriolar Cep152 organization, polo-like kinase 4 (Plk4) relocalization to the procentriole assembly site, and Plk4-mediated centriole duplication. Given that the organization of pericentriolar materials (PCM) is evolutionarily conserved, this work could serve as a model for investigating the structure and function of PCM in other species, while offering a new direction in probing the organizational defects of PCM-related human diseases.

Crystal structure of Escherichia coli thiamine pyrophosphate-sensing riboswitch in the apo state

The thiamine pyrophosphate (TPP)-sensing riboswitch is one of the earliest discovered and most widespread riboswitches. Numerous structural studies have been reported for this riboswitch bound with various ligands. However, the ligand-free (apo) structure remains unknown. Here, we report a 3.1 Å resolution crystal structure of Escherichia coli TPP riboswitch in the apo state, which exhibits an extended, Y-shaped conformation further supported by small-angle X-ray scattering data and driven molecular dynamics simulations. The loss of ligand interactions results in helical uncoiling of P5 and disruption of the key tertiary interaction between the sensory domains. Opening of the aptamer propagates to the gene-regulatory P1 helix and generates the key conformational flexibility needed for the switching behavior. Much of the ligand-binding site at the three-way junction is unaltered, thereby maintaining a partially preformed pocket. Together, these results paint a dynamic picture of the ligand-induced conformational changes in TPP riboswitches that confer conditional gene regulation.

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.

[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.

Determining structures of individual RNA conformers using atomic force microscopy images and deep neural networks

The vast percentage of the human genome is transcribed into RNA, many of which contain various structural elements and are important for functions. RNA molecules are conformationally heterogeneous and functionally dyanmics1, even when they are structured and well-folded2, which limit the applicability of methods such as NMR, crystallography, or cryo-EM. Moreover, because of the lack of a large structure RNA database, and no clear correlation between sequence and structure, approaches like AlphaFold3 for protein structure prediction, do not apply to RNA. Therefore determining the structures of heterogeneous RNA is an unmet challenge. Here we report a novel method of determining RNA three-dimensional topological structures using deep neural networks and atomic force microscopy (AFM) images of individual RNA molecules in solution. Owing to the high signal-to-noise ratio of AFM, our method is ideal for capturing structures of individual conformationally heterogeneous RNA. We show that our method can determine 3D topological structures of any large folded RNA conformers, from ~ 200 to ~ 420 residues, the size range that most functional RNA structures or structural elements fall into. Thus our method addresses one of the major challenges in frontier RNA structural biology and may impact our fundamental understanding of RNA structure.

[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.

[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.

Mix-and-Inject Serial Femtosecond Crystallography to Capture RNA Riboswitch Intermediates

Time-resolved structure determination of macromolecular conformations and ligand-bound intermediates is extremely challenging, particularly for RNA. With rapid technological advances in both microfluidic liquid injection and X-ray free electron lasers (XFEL), a new frontier has emerged in time-resolved crystallography whereby crystals can be mixed with ligand and then probed with X-rays (mix-and-inject) in real time and at room temperature. This chapter outlines the basic setup and procedures for mix-and-inject experiments for recording time-resolved crystallographic data of riboswitch RNA reaction states using serial femtosecond crystallography (SFX) and an XFEL.

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.

Combining Biophysical Methods for Structure-Function Analyses of RNA in Solution

RNA-level regulation by riboswitches relies on the specific binding of small metabolites to the aptamer domain to trigger substantial conformational changes that affect transcription or translation. Although several biophysical methods have been employed to study such RNAs, the utility of any one single method is limited. Hybrid approaches, therefore, are essential to better characterize these intrinsically dynamic molecules and elucidate their regulatory mechanisms driven by ligand-induced conformational changes. This chapter outlines procedures for biochemical and biophysical characterization of RNA that employs a combination of solution-based methods: isothermal titration calorimetry (ITC), small-angle X-ray scattering (SAXS), and atomic force microscopy (AFM). Collectively, these tools provide a semi-quantitative assessment of the thermodynamics associated with ligand binding and subsequent conformational changes.

[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.

[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.

Developing methods to study conformational changes in RNA crystals using a photocaged ligand

Crystallographic observation of structural changes in real time requires that those changes be uniform both spatially and temporally. A primary challenge with time-resolved ligand-mixing diffraction experiments is asynchrony caused by variable factors, such as efficiency of mixing, rate of diffusion, crystal size, and subsequently, conformational heterogeneity. One method of minimizing such variability is use of a photolabile caged ligand, which can fully saturate the crystal environment (spatially), and whose photoactivation can rapidly (temporally) trigger the reaction in a controlled manner. Our recently published results on a ligand-mixing experiment using time-resolved X-ray crystallography (TRX) with an X-ray free electron laser (XFEL) demonstrated that large conformational changes upon ligand binding resulted in a solid-to-solid phase transition (SSPT), while maintaining Bragg diffraction. Here we investigate this SSPT by polarized video microscopy (PVM) after light-triggered release of a photo-caged adenine (pcADE). In general, the mean transition times and transition widths of the SSPT were less dependent on crystal size than what was observed in previous PVM studies with direct ADE mixing. Instead, the photo-induced transition appears to be heavily influenced by the equilibrium between caged and uncaged ADE due to relatively low sample exposure and uncaging efficiency. Nevertheless, we successfully demonstrate a method for the characterization of phase transitions in RNA crystals that are inducible with a photocaged ligand. The transition data for three crystals of different sizes were then applied to kinetic analysis by fitting to the known four-state model associated with ligand-induced conformational changes, revealing an apparent concentration of uncaged ADE in crystal of 0.43–0.46 mM. These results provide further insight into approaches to study time-resolved ligand-induced conformational changes in crystals, and in particular, highlight the feasibility of triggering phase transitions using a light-inducible system. Developing such approaches may be paramount for the rapidly emerging field of time-resolved crystallography.

Taf2 mediates DNA binding of Taf14

The assembly and function of the yeast general transcription factor TFIID complex requires specific contacts between its Taf14 and Taf2 subunits, however, the mechanism underlying these contacts remains unclear. Here, we determined the molecular and structural basis by which the YEATS and ET domains of Taf14 bind to the C-terminal tail of Taf2 and identified a unique DNA-binding activity of the linker region connecting the two domains. We show that in the absence of ligands the linker region of Taf14 is occluded by the surrounding domains, and therefore the DNA binding function of Taf14 is autoinhibited. Binding of Taf2 promotes a conformational rearrangement in Taf14, resulting in a release of the linker for the engagement with DNA and the nucleosome. Genetic in vivo data indicate that the association of Taf14 with both Taf2 and DNA is essential for transcriptional regulation. Our findings provide a basis for deciphering the role of individual TFIID subunits in mediating gene transcription.

[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.

[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.

High efficiency and collimated terahertz pulse from ultra-short intense laser and cone target

We propose a new, to the best of our knowledge, method to radiate a high-efficiency and collimated terahertz (THz) pulse from a relativistic femtosecond laser and cone target. Particle-in-cell simulations demonstrate that a THz source of 40 mJ, pointing at an angle of ∼20 ^∘, can be generated from a laser pulse of 1.9 J by using a cone target whose open angle is 10 ^∘. The peak power of the THz pulse is 10¹¹ W. This method, which manipulates the divergence angle and the energy conversion efficiency of the THz source, should promote THz science into the extra strong region with a compact laser system.

[Metagenomic data-analysis reveals enrichment of lipopolysaccharide synthesis in the gut microbiota of atrial fibrillation patients]

Objective: To investigate the functional changes of key gut microbiota (GM) that produce lipopolysaccharide (LPS) in atrial fibrillation (AF) patients and to explore their potential role in the pathogenesis of AF. Methods: This was a prospective cross-sectional study. Patients with AF admitted to Beijing Chaoyang Hospital of Capital Medical University were enrolled from March 2016 to December 2018. Subjects with matched genetic backgrounds undergoing physical examination during the same period were selected as controls. Clinical baseline data and fecal samples were collected. Bacterial DNA was extracted and metagenomic sequencing was performed by using Illumina Novaseq. Based on metagenomic data, the relative abundances of KEGG Orthology (KO), enzymatic genes and species that harbored enzymatic genes were acquired. The key features were selected via the least absolute shrinkage and selection operator (LASSO) analysis. The role of GM-derived LPS biosynthetic feature in the development of AF was assessed by receiver operating characteristic (ROC) curve, partial least squares structural equation modeling (PLS-SEM) and logistic regression analysis. Results: Fifty nonvalvular AF patients (mean age: 66.0 (57.0, 71.3), 32 males(64%)) were enrolled as AF group. Fifty individuals (mean age 55.0 (50.5, 57.5), 41 males(82%)) were recruited as controls. Compared with the controls, AF patients showed a marked difference in the GM genes underlying LPS-biosynthesis, including 20 potential LPS-synthesis KO, 7 LPS-biosynthesis enzymatic genes and 89 species that were assigned as taxa harbored nine LPS-enzymatic genes. LASSO regression analysis showed that 5 KO, 3 enzymatic genes and 9 species could be selected to construct the KO, enzyme and species scoring system. Genes enriched in AF group included 2 KO (K02851 and K00972), 3 enzymatic genes (LpxH, LpxC and LpxK) and 7 species (Intestinibacter bartlettii、Ruminococcus sp. JC304、Coprococcus catus、uncultured Eubacterium sp.、Eubacterium sp. CAG:251、Anaerostipes hadrus、Dorea longicatena). ROC curve analysis revealed the predictive capacity of differential GM-derived LPS signatures to distinguish AF patients in terms of above KO, enzymatic and species scores: area under curve (AUC)=0.957, 95%CI: 0.918-0.995, AUC=0.940, 95%CI 0.889-0.991, AUC=0.972, 95%CI 0.948-0.997. PLS-SEM showed that changes in lipopolysaccharide-producing bacteria could be involved in the pathogenesis of AF. The key KO mediated 35.17% of the total effect of key bacteria on AF. After incorporating the clinical factors of AF, the KO score was positively associated with the significantly increased risk of AF (OR<0.001, 95%CI:<0.001-0.021, P<0.001). Conclusion: Microbes involved in LPS synthesis are enriched in the gut of AF patients, accompanied with up-regulated LPS synthesis function by encoding the LPS-enzymatic biosynthesis gene.

OUP accepted manuscript

Subdomain 5BSL3.2 of hepatitis C virus RNA lies at the core of a network of distal RNA–RNA contacts that connect the 5′ and 3′ regions of the viral genome and regulate the translation and replication stages of the viral cycle. Using small-angle X-ray scattering and NMR spectroscopy experiments, we have determined at low resolution the structural models of this subdomain and its distal complex with domain 3′X, located at the 3′-terminus of the viral RNA chain. 5BSL3.2 adopts a characteristic ‘L’ shape in solution, whereas the 5BSL3.2–3′X distal complex forms a highly unusual ‘Y’-shaped kissing junction that blocks the dimer linkage sequence of domain 3′X and promotes translation. The structure of this complex may impede an effective association of the viral polymerase with 5BSL3.2 and 3′X to start negative-strand RNA synthesis, contributing to explain the likely mechanism used by these sequences to regulate viral replication and translation. In addition, sequence and shape features of 5BSL3.2 are present in functional RNA motifs of flaviviruses, suggesting conserved regulatory processes within the Flaviviridae family.

[Morphological parameters of the posterior pole in a high myopia population aged over 40 years: a 10-year follow-up study]

Objective To study the long-term changes of the morphological parameters of the posterior pole in highly myopic patients over 40 years old in Chinese natural population. Methods A population-based follow-up study. The study included 71 patients (27 males, 44 females; 110 eyes) with high myopia who completed the Beijing Eye Study in 2001 and 2011 and had assessable color fundus photographs. The age of the patients in 2011 was 56.2±9.5 years old. According to the definition of pathological myopia by the meta-analysis of the Pathological Myopia Research Group, the fundus photos in 2001 were interpreted, and 110 eyes were divided into groups of simple high myopia (79 eyes) and pathological myopia (31 eyes). The morphological parameters during the 2 follow-up visits in 2001 and 2011 were measured in the color fundus photos, including optic disc tilt ratio, optic disc rotation degree, β zone area, disc-fovea distance, disc-outer β zone border distance, fovea-outer β zone border distance, and vertical distance between temporal arterial arcades, and compared in all the subjects, patients with simple high myopia and patients with pathological myopia. Correlations between the 10-year changes of these parameters and other parameters were analyzed using multiple linear regression analysis. Results In all subjects, the incidence of optic disc tilt and rotation was 41.1% (44/107) and 63.3% (68/107), respectively. The optic disc tilt ratio in 2001 and 2011 was 1.34±0.31 and 1.34±0.33, respectively. The optic disc rotation degree was 30.4±26.3° and 30.0±25.3 in 2001 and 2011, respectively. The differences in optic disc tilt ratio (Z=-0.317, P>0.05) and optic disc rotation degree (t=0.159, P>0.05) were not statistically significant. The β zone area [1.34 (0.45,3.73)mm², Z=-7.295, P<0.05], disc-fovea distance [(5.18±0.54)mm, t=-3.523, P<0.05], and disc-outer β zone border distance [1.55 (0.24,2.16)mm, Z=-6.825, P<0.05] in 2011 were significantly increased compared to those in 2001 [1.05 (0.23,1.88)mm², 5.08±0.43, 1.39 (0.77,1.93)mm]. There was no statistically significant difference in the vertical distance between temporal arterial arcades (Z=-1.858, P>0.05). The fovea-outer β zone border distance in the simple high myopia group in 2011 was significantly shorter than that in 2001 (Z=-3.221, P<0.05), while there was no significant change in this parameter in the pathological myopia group (t=0.655, P<0.05). In multivariate analysis, larger β zone area was significantly correlated with longer corneal curvature (r=0.462, P<0.05) and longer axial length (P<0.05). Longer disc-fovea distance was significantly correlated with lower best corrected visual acuity (r=0.348, P<0.05) and longer axial length (P<0.05). Similarly, longer disc-outer β zone border distance was related to lower best corrected visual acuity (r=0.538, P<0.05) and longer axial length (P<0.05). In addition, the progression of myopic maculopathy (Z=-3.425, P<0.05) and the progression from simple high myopia to pathological myopia (Z=-2.911, P<0.05) were both related to enlargement of the β zone. Conclusion For patients with high myopia aged over 40 years, the optic disc morphology is relatively stable, while the disc-fovea distance and β zone area will continue to increase with the progression of myopia. This may be due to the elongation of axial length. Enlargement of the β zone may be a predictor for the progression of myopic maculopathy. (Chin J Ophthalmol, 2021, 57:908-915).

[Prevention and treatment of hyperkalemia in chronic kidney disease]

Hyperkalemia is a common electrolyte disorder in patients with chronic kidney disease, and can be life-threatening in severe cases. It is an emergency that every clinician should recognize and master. This paper briefly describes the risk of hyperkalemia in order to pay more attention to hyperkalemia, summarizes the strategies for the treatment of hyperkalemia and reviews different treatment methods, so as to provide ideas for the treatment of hyperkalemia and improve the prognosis of patients.