Objective The effect of sciatic neurectomy(SN)on the meso-mechanical properties of cortical bone was explored by combining animal modeling and resonant ultrasound spectroscopy.Methods A total of five New Zealand White rabbits underwent unilateral SN,and cortical bone specimens were obtained from the tibias on the operated and normal sides at 4th week after SN;multiple elastic constants(C11,C12,C13,C33,and C44),engineering mechanical parameters,and anisotropy ratios of the bone specimens were acquired using irregular resonant ultrasound spectroscopy under assumptions of transverse anisotropy,and the paired t-test was used to assess the differences in mechanical properties of the cortical bone between the two sides.Results Compared with the normal side,the elastic constants in different directions(C11,C12,C13,and C33)of the cortical bone on the operated side showed a decreasing trend,ranging from 8.49％to 32.23％;the axial elastic modulus(E3)and Poisson's ratio(v31)were reduced by 5.85％and 24.07％,respectively,but there were no significant changes in the anisotropic properties.Conclusions The method of cortical bone disuse modeling through SN is feasible.This method can significantly change meso-mechanical properties of the cortical bone,and the elastic constants can more comprehensively reflect the changes in mechanical properties of the cortical bone.

Objective The effect of sciatic neurectomy(SN)on the meso-mechanical properties of cortical bone was explored by combining animal modeling and resonant ultrasound spectroscopy.Methods A total of five New Zealand White rabbits underwent unilateral SN,and cortical bone specimens were obtained from the tibias on the operated and normal sides at 4th week after SN;multiple elastic constants(C11,C12,C13,C33,and C44),engineering mechanical parameters,and anisotropy ratios of the bone specimens were acquired using irregular resonant ultrasound spectroscopy under assumptions of transverse anisotropy,and the paired t-test was used to assess the differences in mechanical properties of the cortical bone between the two sides.Results Compared with the normal side,the elastic constants in different directions(C11,C12,C13,and C33)of the cortical bone on the operated side showed a decreasing trend,ranging from 8.49％to 32.23％;the axial elastic modulus(E3)and Poisson's ratio(v31)were reduced by 5.85％and 24.07％,respectively,but there were no significant changes in the anisotropic properties.Conclusions The method of cortical bone disuse modeling through SN is feasible.This method can significantly change meso-mechanical properties of the cortical bone,and the elastic constants can more comprehensively reflect the changes in mechanical properties of the cortical bone.

Objective To clarify the characteristics of shock wave sources generated at different medium interfaces.Methods The experiment used an in vitro adjustable impact pressure shock wave generation and signal acquisition system combined with a flexible PVDF sensor.The waveform of the shock wave generated by the applicator at the interface of different media(soft tissue-mimicking phantom,water and air)was explored.The characteristics of the shock wave source in the time and frequency domains were analyzed.Results When the same impact pressure was applied,shock waveforms generated at the interfaces of the phantom and water exhibited similar characteristics from a time-domain perspective.At the same time,both differed significantly from those generated at the air interface,where the absolute values of the positive and negative pressures were noticeably reduced.The characteristics of the shockwave spectra in various media revealed three distinct peak frequencies,with the modulation frequencies varying in the phantom(12.2 kHz),water(8.5 kHz),and air(7.2 kHz).In contrast,the carrier frequency remained relatively constant(between 82 and 83 kHz).When different impact pressures were applied,there was little influence on the waveform at the same medium interface,indicating that the impact pressure affected only the shockwave amplitude and not the peak frequency.As the impact pressure increases,the absolute values of the positive and negative pressures at the medium interface increase linearly.Conclusions Shockwave sources can be effectively measured using a flexible PVDF sensor.Shock waves generated at different medium interfaces exhibit temporal and spectral differences,indicating that the characteristics of shock wave propagation in air or water cannot be substituted for those in biological soft tissues.These findings provide crucial information for evaluating shockwave devices and formulating treatment protocols in the clinic.

Objective:The transjugular or transfemoral approach is used as a common method for hepatic venous pressure gradient (HVPG) measurement in current practice. This study aims to confirm the safety and effectiveness of measuring HVPG via the forearm venous approach.Methods:Prospective recruitment was conducted for patients with cirrhosis who underwent HVPG measurement via the forearm venous approach at six hospitals in China and Japan from September 2020 to December 2020. Patients' clinical baseline information and HVPG measurement data were collected. The right median cubital vein or basilic vein approach for all enrolled patients was selected. The HVPG standard process was used to measure pressure. Research data were analyzed using SPSS 22.0 statistical software. Quantitative data were used to represent medians (interquartile ranges), while qualitative data were used to represent frequency and rates. The correlation between two sets of data was analyzed using Pearson correlation analysis.Results:A total of 43 cases were enrolled in this study. Of these, 41 (95.3%) successfully underwent HVPG measurement via the forearm venous approach. None of the patients had any serious complications. The median operation time for HVPG detection via forearm vein was 18.0 minutes (12.3~38.8 minutes). This study confirmed that HVPG was positively closely related to Child-Pugh score ( r = 0.47, P = 0.002), albumin-bilirubin score ( r = 0.37, P = 0.001), Lok index ( r = 0.36, P = 0.02), liver stiffness ( r = 0.58, P = 0.01), and spleen stiffness ( r = 0.77, P = 0.01), while negatively correlated with albumin ( r = -0.42, P = 0.006). Conclusion:The results of this multi-centre retrospective study suggest that HVPG measurement via the forearm venous approach is safe and feasible.

Objective:To investigate the prevalence of cataracts, the surgical coverage, and postoperative visual acuity of adults in Ningxia.Methods:A cross-sectional study using multistage cluster random sampling was conducted.Ten survey sites in Ningxia were selected and the population aged 18 years and over was surveyed with questionnaire, height and weight measurements, visual acuity, intraocular pressure, fundus photography and slit-lamp examinations.Cataract prevalence and its influencing factors were analyzed.Cataract prevalence, surgical coverage and presenting visual acuity (PVA) and best corrected visual acuity (BCVA) after surgery were investigated in different age groups of the examined population.The study adhered to the Declaration of Helsinki and was approved by the Ethics Committee of the People's Hospital of Ningxia Hui Autonomous Region (No.[2023]-LL-010).Participants signed informed consent prior to the examination.Results:A total of 6 145 people should be examined, and 5 721 people were actually examined, with an examination rate of 93.10%.The study population consisted of 2 558 males, accounting for 44.71%, and 3 163 females, accounting for 55.28%, with ages ranging from 18 to 93 years old and an average age of (64.27±13.48) years.Among them, 1 180 patients diagnosed with cataract, with a cataract prevalence of 20.62%.The prevalence of cataract increased with age and decreased with education level, showing statistically significant differences ( χ2=1 091.32, 581.92; both at P<0.01).The prevalence of cataract was significantly higher among people with hypertension, diabetes mellitus, hyperlipidemia, and coronary heart disease than those without these diseases ( χ2=274.65, 118.15, 78.05, 182.71; all at P<0.01).Cataract surgery was performed in 245 cases in the cataract patient population, with a surgical coverage rate of 20.76%.Of the 245 cases, 229 cases were implanted with IOLs, with an implantation rate of 93.40%.The social burden rate of cataract blindness was 2.29%, and increased with age.Of the 339 eyes that underwent cataract surgery, 241 had a PVA≥0.3, accounting for 71.09%, and 272 had a BCVA≥0.3, accounting for 80.24%. Conclusions:In Ningxia, cataracts are still the main cause of vision impairment and blindness in the elderly, and the social burden rate of cataract blindness is high.Moreover, the coverage rate of cataract surgery is low, so both the coverage and quality of surgery need improvement.

Objective:To analyze the metabolic status of forest encephalitis patients, research the effect of forest encephalitis on lipid metabolism, and clarify the possible pathogenesis.Methods:Based on liquid chromatography-mass spectrometry (LC-MS), lipidomics analysis was performed in 50 patients with tick-borne encephalitis and 39 healthy samples from Hulunbuir region. The patients′ serum samples were analyzed by utilizing the multivariate statistical analysis method such as principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA).Results:A total of 465 peaks were detected in the samples, and metabolites such as phospholipids and glycerides were identified. To identify the significant differential metabolites ( P<0.01, VIP>1, FC>2), a total of 26 biomarkers were screened, which phospholipids tend to be upregulated[log 2(Fold change)>0], such as phosphatidylcholine (PC) and phosphatidylethanolamine (PE); while glycerides tend to be decreased[log 2(Fold change)<0], such as diacylglycerol (DAG) and triacylglycerol (TAG), and those metabolites were closely related to anti-inflammatory and other metabolic pathways. The AUC value of potential biomarkers obtained was 0.999, which could be used for diagnosis of disease group and healthy group. Conclusions:The study showed that phospholipid metabolism and glyceride metabolism pathways would have some change after human infected by virus, and the differential metabolites could be used as potential markers for the diagnosis of tick-borne encephalitis, which provide a theoretical basis for disease research.

OBJECTIVE: Exploring the effectiveness of using EEG linear and nonlinear features for accessing mental workload in different tasks. METHODS: Working memory tasks with different information types and various mental loads were designed based on N-Back paradigm. EEG signals from 18 normal adults were acquired when tasks were being performed. Linear and nonlinear features of EEGs were then extracted. Indices that can effectively reflect mental workload levels were selected by using multivariate analysis of variance statistical approach. RESULTS: With the increment of task load, power of frontal Theta, Theta/Alpha ratio, and sample entropies (scales>10) in parietal regions increased significantly first and decreased slightly then, while the power of central-parietal Alpha decreased significantly first and increased slightly then. No difference in power of frontal Theta, central-parietal Alpha, and sample entropies (scales>10) of parietal regions were found between verbal and object tasks, as well as between two spatial tasks. No difference of frontal Theta/Alpha ratio was found in all the four tasks. CONCLUSIONS The results can provide evidence for the mental workload evaluation in tasks with different information types.
Electroencephalography ; Memory, Short-Term ; Workload

Objective:To investigate the clinical application value of peripheral blood methylation Septin9 gene in peripheral blood combined with SDC2 gene methylation and TFPI2 gene methylation and fecal occult blood test in colorectal lesion screening.Methods:Through random-selection method. Seventy-five patients with colorectal cancer and 50 patients with advanced adenoma who were treated in our hospital from January 2017 to June 2019 were enrolled as the colorectal cancer group and the advanced adenocarcinoma group, respectively, and the results of the negative test were used as controls Methylation-specific PCR (MSP) was used to detect the methylation status of the Septin9, SDC2 and TFPI2 genes in all patients and the fecal occult blood test for colorectal cancer and advanced adenocarcinoma. In addition, the receiver operating characteristic curve (ROC curve) was drawn to compare the diagnostic value of combined detection and individual detection.Results:The positive rate of Septin9, SDC2, TFPI2 methylation and FOBT in colorectal cancer group was 53.04% (61/115 cases), 55.65% (64/115 cases), 59.13% (68/115 cases) and 26.09% (30/115 cases), respectively. The positive detection rates of Septin9, SDC2, TFPI2 methylation and FOBT in the advanced adenoma group were 33.33% (30/90 cases), 50% (45/90 cases), 40.00% (36/90 cases) and 17.78% (16/90 cases), respectively. The detection sensitivity (82.7%) was higher than the sensitivity of each single test and combined detection of SDC2 and TFPI2 gene methylation: Septin9 methylation (66.7%), SDC2 methylation (69.3%), TFPI2 methylation (73.3%), FOBT (26.7%), SDC2 and TFPI2 methylation combined detection (77.3%), while maintaining a high specificity (80.0%). Septin9, SDC2, TFPI2 gene methylation joint inspection screening advanced adenomas detection sensitivity (70.0%) was higher than the sensitivity of each single test and combined detection of SDC2 and TFPI2 gene methylation: (40.0%), SDC2 Septin9 gene methylation gene methylation (64.0%), TFPI2 methylation (50.0%), FOBT (18.0%), SDC2 and TFPI2 gene methylation detection (64.0%), and also maintained a high specificity (82.5%). ROC curve analysis showed that the area under the ROC curve of the three gene methylation combined screening for colorectal cancer was significantly higher than that of Septin9, SDC2, TFPI2 gene methylation, FOBT alone, and SDC2 combined with TFPI2 gene methylation detection (0.684, 0.765, 0.623, 0.796 and 0.566), and the difference was statistically significant ( P<0.05); and the area under the ROC curve of three gene methylation combined screening screening for advanced adenomas was significantly higher than the area under the ROC curve of Septin9, SDC2, TFPI2 gene methylation, FOBT alone, and SDC2 combined with TFPI2 gene methylation (0.568, 0.685, 0.535, 0.723 and 0.489), and the difference was statistically significant ( P<0.05). Conclusions:Combined detection of Septin9, SDC2 and TFPI2 gene methylation can improve the sensitivity of colorectal lesion diagnosis and maintain high specificity. It has the clinical application value for early screening and diagnosis and treatment of colorectal cancer.

Aging is a major risk factor for diseases such as osteoarthritis (OA) and osteoporosis. However, they are not necessarily the results of aging, and the relationship between changes in bone and cartilage associated with aging and disease progression is still unclear. Studies have shown that the development and progression of OA is not a simple cartilage wear process, while its occurrence involves complex biological, chemical and mechanical changes in the tissues of the entire joint, especially the interaction of mechanics and biochemistry between cartilage and subchondral bone. Aging contributes to the occurrence and development of OA, but it is not the cause of OA. Changes associated with aging provide a foundation for OA to start, making joints more susceptible to other factors such as abnormal biomechanics and biochemistry, thereby promoting the development of OA. Therefore, understanding the basic mechanisms by which aging affects joint tissue may provide new targets for slowing or preventing the development of OA. In this paper, the related research progresses are reviewed from three aspects, i.e. age-related changes in cartilage and subchondral bone, mechanical conduction and angiogenesis.