Study on the influence of rock bridge angle on the size effect of rock uniaxial compression.

As a basic parameter of rock, the rock bridge angle plays an important role in maintaining the stability of rock masses. To study the size effect of rock bridge angle on the uniaxial compressive strength of rocks, this paper adopts the principle of regression analysis and combines numerical simulation to carry out relevant research. The research results indicate that: (1) the uniaxial compressive strength decreases with the increase of the rock bridge angle, showing a power function relationship; (2) The uniaxial compressive strength decreases with the increase of rock size and tends to stabilize when the rock size is greater than 350 mm, showing a significant size effect. (3) The fluctuation coefficient of compressive strength increases with the increase of rock bridge angle and decreases with the increase of rock size; When the rock size is 350 mm, the fluctuation coefficient is less than 5%; (4) The characteristic compressive strength and characteristic size both increase with the increase of the rock bridge angle.

Bridging the Gap Between Morphometric Similarity Mapping and Gene Transcription in Alzheimer's Disease.

Disruptions in brain connectivity have been widely reported in Alzheimer's disease (AD). Morphometric similarity (MS) mapping provides a new way of estimating structural connectivity by interregional correlation of T1WI- and DTI-derived parameters within individual brains. Here, we aimed to identify AD-related MS changing patterns and genes related to the changes and further explored the molecular and cellular mechanism underlying MS changes in AD. Both 3D-T1WI and DTI data of 106 AD patients and 106 well-matched healthy elderly individuals from the ADNI database were included in our study. Cortical regions with significantly decreased MS were found in the temporal and parietal cortex, increased MS was found in the frontal cortex and variant changes were found in the occipital cortex in AD patients. Mean MS in regions with significantly changed MS was positively or negatively associated with memory function. Negative MS-related genes were significantly downregulated in AD, specifically enriched in neurons, and participated in biological processes, with the most significant term being synaptic transmission. This study revealed AD-related cortical MS changes associated with memory function. Linking gene expression to cortical MS changes may provide a possible molecular and cellular substrate for MS abnormality and cognitive decline in AD.

Cell-Type-Specific Gene Modules Related to the Regional Homogeneity of Spontaneous Brain Activity and Their Associations With Common Brain Disorders.

Mapping gene expression profiles to neuroimaging phenotypes in the same anatomical space provides opportunities to discover molecular substrates for human brain functional properties. Here, we aimed to identify cell-type-specific gene modules associated with the regional homogeneity (ReHo) of spontaneous brain activity and their associations with brain disorders. Fourteen gene modules were consistently associated with ReHo in the three datasets, five of which showed cell-type-specific expression (one neuron-endothelial module, one neuron module, one astrocyte module and two microglial modules) in two independent cell series of the human cerebral cortex. The neuron-endothelial module was mainly enriched for transporter complexes, the neuron module for the synaptic membrane, the astrocyte module for amino acid metabolism, and microglial modules for leukocyte activation and ribose phosphate biosynthesis. In enrichment analyses of cell-type-specific modules for 10 common brain disorders, only the microglial module was significantly enriched for genes obtained from genome-wide association studies of multiple sclerosis (MS) and Alzheimer's disease (AD). The ReHo of spontaneous brain activity is associated with the gene expression profiles of neurons, astrocytes, microglia and endothelial cells. The microglia-related genes associated with MS and AD may provide possible molecular substrates for ReHo abnormality in both brain disorders.

[Shuxuening injection combined with routine therapy in treating patients with active ulcerative colitis: an analysis of efficacy ].

OBJECTIVE: To observe the therapeutic effect and relevant mechanism of shuxuening Injection (SI) in treating patients with active ulcerative colitis (UC). METHODS: Totally 91 patients with active UC were randomly assigned to 2 groups, 44 in the control group and 47 in the treatment group. Patients in the control group received routine treatment, while patients in the treatment group additionally received intravenous injection of SI (15 mL), twice daily for 14 days in total. Colonoscopy was performed before and after treatment. The therapeutic effect was assessed by Mayo scoring system and the grading of activities evaluated by Baron endoscope. Serum levels of IL-6 and TNF-α were detected by ELISA. The activity of SOD was detected by xanthine oxidase method. The content of MDA was detected by thiobarbituricacid (TBA). Besides, 20 healthy subjects were recruited as the healthy control group. RESULTS: Totally 82 patients completed the study (40 in the control group and 42 in the treatment group). There was no statistical difference in serum levels of IL-6, TNF-α, SOD, MDA, the Mayo score and endoscope grading between the two groups before treatment (P >0. 05). Compared with the healthy control group, serum levels of IL-6, TNF-α, MDA significantly increased (P <0.01), and the serum SOD level decreased (P < 0. 05) in the treatment grup and the control group before treatment. Compared with before treatment in the same group, serum levels of IL-6, TNF-α, MDA, the Mayo score and endoscope grading all decreased in the treatment group and the control group after treatment (P <0. 01, P <0. 05). Compared with the control group after treatment, serum levels of IL-6, TNF-α, MDA, the Mayo score and endoscope grading all decreased (P <0.01, P <0.05), the serum SOD level increased (P <0.05) in the treatment group after treatment. The serum SOD level was obviously negative correlated with serum levels of IL-6, TNF-a, Mayo score, and endoscope score (r = -0. 621, -0.638, -0. 509, -0.787, P <0.01). The serum MDA level was obviously positive correlated with serum levels of IL-6, TNF-α, Mayo score, and endoscope score (r =0.711, 0. 882, 0. 525, 0. 639, P <0.01). CONCLUSION: SI could improve inflammatory injury and clinical symptoms of patients with active UC, and its mechanism might be associated with antioxidant and scavenging oxygen free radicals.

[Effects of shuxuening injection on the levels of serum matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in acute exacerbated chronic obstructive pulmonary disease patients].

OBJECTIVE: To observe the effects of Shuxuening Injection (SI) on the levels of serum matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase (TIMP-1) in acute exacerbated chronic obstructive pulmonary disease (COPD) patients. METHODS: Seventy-nine patients with acute exacerbated COPD were randomly assigned to the treatment group (39 cases) and the control group (40 cases). Routine therapies for COPD were given to patients in the control group, while 15 mL SI was given to those in the treatment group by intravenous dripping, twice daily for total 14 days. The forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were detected by Spirometer. The FEV1/FVC (%) and the FEV1% were calculated. The levels of serum MMP-9 and TIMP-1 were detected using ELISA before and after treatment, and compared with 20 healthy subjects as the control. RESULTS: The FEV1, FVC, FEV1/FVC (%), and FEV1% were significantly improved after treatment in the treatment group when compared with before treatment and with the control group (P < 0.05, P < 0.01). When compared with before treatment and with the control group, the levels of serum MMP-9, TIMP-1, and the ratio of MMP-9/TIMP-1 decreased more significantly in the treatment group after treatment (P < 0.01). Correlation analyses showed that obvious negative correlation existed between the levels of serum MMP-9 and TIMP-1 and FEV1/FVC (%) (r = -0.677, -0.629, P < 0.01). Obvious negative correlation existed between the levels of serum MMP-9 and TIMP-1 and FEV1% (r = -0.562, -0.661, P < 0.01). Furthermore, obvious negative correlation also existed between the ratio of MMP-9/ TIMP-1 and FEV1%, as well as FEV1/FVC (%) (r = -0.732, -0.891, P < 0.01). CONCLUSIONS: SI could improve the pulmonary ventilation function of acute exacerbated COPD patients. One of its mechanisms might be correlated with lowering the serum levels of MMP-9 and TIMP-1, and correcting the imbalance of MMP-9/TIMP-1.

[The measurement and analyses of symmetry characteristic of human skull based on CT images].

Two kinds of algorithm have been set forth to estimate the symmetry characteristic of live human skull on CT image. These CT images were treated with a series of processes such as coding into programs, formatting originals, binary coding, rectifying image deviation, detecting boundary edge, and quantitatively measuring the skull symmetry. The statistical analyses of measuring 3000 live human skull images have worked out the ratio and the distribution of the skull symmetry, so that dependable data are provided for establishing the human head injury biomechanics model. The results are of great practical value in the fields of anatomy, clinical medicine, biomechanies study, head injury analysis, etc.

[The thickness measurement of alive human skull based on CT image].

This study sought to measure accurately the thickness of the frontal, parietal and occipital bones of the alive human skull based on CT images. The images were treated with a series of processes by coding into a program: image segmentation and binary coding; eliminating edge interference; rectifying image deviation and clarifying boundary edge; redrawing the boundary and reference point fixing; and finally thickness measurement. The new method can measure not only the different points in one CT image but also the same point in massive CT images. The measurement results are of great practical value in the fields of anatomy, clinical medicine, biomechanics study, head injury analysis, etc.