The role and mechanism of biological collagen membranes in repairing cartilage injury through the p38MAPK signaling pathway.

OBJECTIVE: To explore the mechanism of the p38MAPK signaling pathway in repairing articular cartilage defects with biological collagen membranes. METHODS: Thirty-two healthy adult male rabbits were randomly divided into a control group (n = 8), model group (n = 8), treatment group (n = 8) and positive drug group (n = 8). The control group was fed normally, and the models of bilateral knee joint femoral cartilage defects were established in the other three groups. The knee cartilage defects in the model group were not treated, the biological collagen membrane was implanted in the treatment group, and glucosamine hydrochloride was intragastrically administered in the positive drug group. Twelve weeks after the operation, the repair of cartilage defects was evaluated by histological observation (HE staining and Masson staining), the degree of cartilage repair was quantitatively evaluated by the Mankin scoring system, the mRNA expression levels of p38MAPK, MMP1 and MMP13 were detected by real-time fluorescence quantitative PCR (qRT-PCR), and the protein expression levels of p38MAPK, p-p38MAPK, MMP1 and MMP13 were detected by Western blotting. The results after the construction of cartilage defects, histological staining showed that the articular cartilage wound was covered by a large capillary network, the cartilage tissue defect was serious, and a small amount of collagen fibers were formed around the wound, indicating the formation of a small amount of new bone tissue. In the treatment group and the positive drug group, the staining of cartilage matrix was uneven, the cytoplasmic staining was lighter, the chondrocytes became hypertrophic as a whole, the chondrocytes cloned and proliferated, some areas were nest-shaped, the cells were arranged disorderly, the density was uneven, and the nucleus was stained deeply. The Mankin score of the model group was significantly higher than that of the control group, while the Mankin scores of the treatment group and positive drug group were significantly lower than that of the model group. The results of qRT-PCR detection showed that compared with the control group, the expression level of the p38MAPK gene in the model group did not increase significantly, but the gene expression levels of MMP1 and MMP13 in the model group increased significantly, while the gene expression levels of MMP1 and MMP13 decreased significantly in the treatment group and positive drug group compared with the model group. The results of Western blot detection showed that compared with the control group, the expression level of p38MAPK protein in the model group was not significantly increased, but the phosphorylation level of p38MAPK protein and the protein expression levels of MMP1 and MMP13 were significantly increased in the model group, while the phosphorylation level of p38MAPK protein and the protein expression levels of MMP1 and MMP13 in the treatment group and positive drug group were significantly lower than those in the model group. CONCLUSION: The biological collagen membrane can regulate the expression of MMP1 and MMP13 and repair the activity of chondrocytes by reducing the phosphorylation level of p38MAPK and inhibiting the activation of the p38MAPK signaling pathway, thus improving the repair effect of articular cartilage defects in rabbits. The P38MAPK signaling pathway is expected to become an important molecular target for the clinical treatment of cartilage defects in the future.

Access to Sulfur-Containing Bisheterocycles through Base-Promoted Consecutive Tandem Cyclization/Sulfenylation with Elemental Sulfur.

A convenient and efficient tandem cyclization/sulfenylation of o-alkynyl-phenols/-anilines/enaminones for the synthesis of diverse sulfur-containing bisheterocycles has been developed using stable, odorless, and easy-to-handle elemental S8 as a building block under green chemistry conditions. Notably, a one-step simple base-mediated organic transformation affords a benzofuran (indole or chromone) ring and two C-S bonds. Attractive features of this methodology include the absence of a metal catalyst, mild conditions, good functional group tolerance, and valuable product structures.

Microfracture versus Enhanced Microfracture Techniques in Knee Cartilage Restoration: A Systematic Review and Meta-Analysis.

This study aimed to compare the efficacy and safety of the microfracture (MFx) and microfracture augmented (MFx + ) techniques for the treatment of cartilage defects of the knee. The PubMed and EMBASE databases were searched from 1 January, 1950 to 1 May, 2019. RevMan5.3 was used to perform statistical analysis. Relative risk was calculated for binary variables, and weighted mean difference and standardized mean difference (SMD) were measured for continuous variables. The 95% confidence interval (CI) of each variable was assessed. Thirteen trials with 635 patients were included. There was a significant difference in the Lysholm's score (SMD = 0.26, 95% CI: 0.01-0.50, p = 0.04) and magnetic resonance observation of cartilage repair tissue score (SMD = 14.01, 95% CI: 8.01-20.02, p < 0.01) between the MFx and MFx+ groups. There was no significant difference in the Western Ontario and McMaster Universities Osteoarthritis Index score (SMD = - 12.40, 95% CI: -27.50 to 32.71, p = 0.11), International Knee Documentation Committee score (SMD = 8.67, 95% CI: -0.92 to 18.27, p = 0.08), visual analog scale score (SMD = - 0.20, 95% CI: -2.45 to 0.96, p = 0.57), Tegner's score (SMD = 0.26, 95% CI: -0.67 to 1.18, p = 0.59), modified Cincinnati's score (SMD = - 4.58, 95% CI: -14.31 to 5.14, p = 0.36) and modified International Cartilage Repair Society pain score (SMD = 0.09, 95% CI: -0.37 to 0.55, p = 0.70) between the groups. Results of the pooled analyses of the MFx+ and MFx groups suggested that the MFx+ technique is slightly superior to the MFx technique for the treatment of articular cartilage defects of the knee. Further research is required and future studies should include assessments of the outcomes at long-term follow-ups. Trial registration number is PROSPERO CRD42019135803.

Hip Arthroscopic Reduction and Fixation for Adolescent Acetabular Posterior Wall Fracture: A Case Report.

BACKGROUND: Posterior wall fracture is the most common type of acetabular fracture, the traditional open reduction and fixation through the Kocher-Langenbeck approach required a large incision and extensive muscle and soft tissue dissection, resulting in more blood loss, more complications and delayed recovery after the operation. Hip arthroscopy has been widely used in clinical practice but rarely reported in acetabular fractures. CASE PRESENTATION: We present the case of a 14-year-old boy with acetabular posterior wall fracture who was treated with hip arthroscopy reduction and fixation using anchors. He began to walk with partial weight-bearing assisted by double crutches, and returned to school with crutches at 3 days after surgery. Although hip arthroscopy is technically more demanding, it's an optimal choice for selected patients of acetabular fracture with the advantages of less invasive and faster postoperative recovery.

[Study on predicting total acid content and soluble sugar of tomato juice by near infrared optical fiber spectrometer technique].

In order to explore a simple, rapid and efficient tomato quality detection method, in the present experiment near infrared spectroscopy and optical fiber sensing technology were applied to quickly measure the nutrition ingredient content in tomato juice samples. The main instrument used in this experiment was near infrared optical fiber spectrometer in a wavelength range from 900 to 2 500 nm, which measured the absorbance of the tomato juice samples; A collection of one hundred and sixty-four tomato juice samples were selected as the standard samples, the spectra and the corresponding chemical value were measured. Partial least squares (PLS) was adopted to establish the mathematical model of the total acid and soluble sugar content in tomato juice samples, and the regression equation was statistically analysed. The total acid in tomato juice prediction correlation coefficient was 0.967, calibration standard deviation (RMSEC) was 0.133, standard error of prediction (RMSEP) was 0.103; the soluble sugar prediction correlation coefficient is 0.976, calibration standard deviation (RMSEC) was 0.463, and the standard error of prediction (RMSEP) was 0. 460. The above data achieved better forecasting results, which showed that the method of quantitative analysis of tomato fruit multicomponent content was feasible. The method is rapid, simple and can do multicomponent analysis on the same sample simultaneously. It is a promising sensor and gradually becoming a international research focus in sensor field.

[Rapid discriminating hogwash oil and edible vegetable oil using near infrared optical fiber spectrometer technique].

In the present study, a new method using near infrared spectroscopy combined with optical fiber sensing technology was applied to the analysis of hogwash oil in blended oil. The 50 samples were a blend of frying oil and "nine three" soybean oil according to a certain volume ratio. The near infrared transmission spectroscopies were collected and the quantitative analysis model of frying oil was established by partial least squares (PLS) and BP artificial neural network The coefficients of determina- tion of calibration sets were 0.908 and 0.934 respectively. The coefficients of determination of validation sets were 0.961 and 0.952, the root mean square error of calibrations (RMSEC) was 0.184 and 0.136, and the root mean square error of predictions (RMSEP) was all 0.111 6. They conform to the model application requirement. At the same time, frying oil and qualified edible oil were identified with the principal component analysis (PCA), and the accurate rate was 100%. The experiment proved that near infrared spectral technology not only can quickly and accurately identify hogwash oil, but also can quantitatively detect hog- wash oil. This method has a wide application prospect in the detection of oil.

[Application of the burned bone morphology and DNA technology in human identification].

Burned bones have their unique characteristics in investigation of fire disaster/crimes, airplane disaster, explosion and other accidents. To study the morphological changes of skeletal tissue and DNA changes at different incinerating temperature might provide precise standard means to determine genera, sex, and age. Genetic locus was also applied in the above fields. The techniques to extract and detect of DNA in burning bones have been improved in recent years. In this article investigation advancement of analysis of burned bones with the morphology, histology, and molecular biology as well as the latest methods and techniques were reviewed. These results provide a new approach for further research and practice in forensic medicine.

Multiplexed, white-light interferometric fiber-optic sensor matrix with a long-cavity, Fabry-Perot resonator.

A long-cavity, single-mode, fiber-optic Fabry-Perot resonator has been used to develop white-light fiberoptic multiplexed Michelson interferometers (MMIs). The MMI matrix is constructed and demonstrated. We also analyzed the capacity of the long-cavity Fabry-Perot resonator multiplexing technique. The experimental results of a 2 x 2 fiber-optic interferometric sensor matrix are given, and the effects of polarization are discussed.