The ideal scaffold material can reconstruct the morphology, structure and function of tissues and organs. Thus, it has received extensive attention in the field of tissue engineering. With the rapid development of the theories and technologies of naturally-derived biomaterials, it has gradually become a research hotspot in the field of regenerative medicine. Natural biomaterials have high bionics, good biocompatibility and a wide range of sources. Thus, they are very suitable to be used as scaffolds for tissue engineering. According to ingredients and source of raw materials, they can be roughly divided into protein-based biomaterials (collagen, gelatin, silk and fibrin), carbohydrate-based biomaterials (cellulose, chitin/chitosan, alginate and agarose), glycosaminoglycans (hyaluronic acid, chondroitin sulfate) and decellularized extracellular matrix (amniotic membrane, small intestinal submucosa, tendons). Different scaffold materials have unique natural structures and properties. Protein-based biomaterials can affect cell migration and differentiation through polymerization to form a network structure. They can be made into stents alone or used with other synthetic materials based on certain mechanical properties. Carbohydrate biomaterials can carry a large amount of liquid due to their high specific surface area. However, their mechanical properties are poor. Therefore, it is often used in the form of gel with other materials to control the release of cells and growth factors in tendon tissue engineering. Regularly, the anti-inflammatory, viscoelastic, lubricating and highly hydrating properties of glycosaminoglycan biomaterials can be combined with synthetic materials to increase their biocompatibility and hydrophilicity. Compared with the above materials, the decellularized extracellular matrix not only has a more similar extracellular structure and nutrients, but also has certain mechanical properties. Therefore, it can better reconstruct the morphology, structure and function of tissue and organ lesions. Ultimately, the above materials have been paid more and more attention in tissue engineering. The ingenious combination of different materials makes the repair of tendons show better results. In future, naturally-derived biomaterials could have broader clinical prospects and application value.

Objective To evaluate the relationship between field of view (FOV) and quality of CT images. Methods Scanning of the phantoms of spatial resolution and density resolution was performed with FOVs of 25 cm?25 cm, 35 cm?35 cm, and 42 cm?42 cm, respectively, and the spatial resolution and density resolution of CT images with different FOVs were measured. 20 patients underwent CT scanning using 25 cm?25 cm and 35 cm?35 cm FOVs, respectively. The images were evaluated by 3 qualified CT doctors by using a double-blind reading. Results As FOVs changed, the spatial resolution and density resolution were different. The best spatial resolution and density resolution were obtained on 25 cm?25 cm FOV images. The best spatial resolution could distinguish four 0.6 mm-diameter eyelets, and the best density resolution could distinguish five 2.5 mm-diameter eyelets. The CT images with 25 cm?25 cm FOV were obviously better than those with 35 cm?35 cm FOV (P

Objective To explore the feasibility and reasonable of low-dose scan on abdominal angiography in 64-slice spiral helical CT. Methods Phantom test: at 120 KV and from 200 mAs to 30 mAs at an interval of 10 mAs in each image acquisition, it was measured standard deviation (SD) of CT number, high contrast resolution and low contrast resolution, and then analyzed the relationship between the three parameters and the mAs values. Three mAs values were chosen to undertake clinical analysis.Clinical analysis: 90 randomly selected objects with abdominal angiography were divided into three groups,scanning with above three mAs values.Measurement of the SD value at the plain scan images was performed and the enhanced low-dose scan images were used post-processing with three-dimensional volume reconstruction (VR). The VR images were classified into three grades (excellent, moderate, bad) with the blind evaluation of three CT radiologists. The quality-correlation analysis was used between the standard deviation (SD) values of plain scan image and abdominal angiography VR image. Results According to the quality-correlation analysis between the standard deviation (SD) value of plain scan image and abdominal angiography VR image, the area under curve in receiver-operated characteristic (ROC) analysis was 0.921, 0.906 and 0.893 in each three group, respectively. Conclusions The low-dose scan of abdominal angiography is feasible. 80mAs can ensure better image quality. The enhanced scan probably can use 60mAs when the SD value is less than 5.78 in the plain scan; but when the SD value of plain scan is greater than 11.8, the enhanced scan is used best 100 mAs or higher.

Objective To investigate the efficacy of individualized interferon (IFN)-alpha therapy in HBeAg-negative chronic hepatitis B patients. Methods Seventy- six Chinese HBeAg-negative chronic hepatitis B patients proven by liver biopsy were treated with 5 MU recombinant IFN-alpha 1b subcutaneously thrice every week. All the patients were followed up for at least 24 months the combined responses were defined as normalization of serum alanine transaminase (ALT) and HBV DNA＜3 log10 copy/mL. An intention-to-treat (ITT) analysis was used in this paper in which all 76 patients were included. Results Six patients were lost. Treatment duration was in the range 2-24 months with a median of 8.5 months, and combined responses were achieved at a median of 6.0 months (range 2-19 months) of treatment duration.Seventy-five-percentile of treatment duration to endpoints was 10.0 months. The combined response rate was 46.1% (35/76) at the end of treatment, 43.3% (33/76) at 12-month follow-up and 40.8% (31/76) at 24-month follow-up. The relapse rate was 20. 0% (7/35) and 25. 7% (9/35) at 12-month and 24-month follow-up, respectively. Higher necroinflammatory activity in liver biopsy predicted a good response, while gender, age, liver fibrosis, baseline ALT, aspartate aminotransferase levels and baseline HBV DNA levels were not impact factors of therapeutic effects by binary Logistic regression analysis.Conclusion Individualized prolonged IFN-alpha regimen lead to considerable sustained disease suppression in patients with HBeAg-negative chronic hepatitis B.

OBJECTIVETo assess the diagnostic value of multiplex ligation-dependent probe amplification (MLPA) for detection of common chromosome aneuploidy in amniotic fluid (AF) cells in order to obtain an accurate, rapid, cost-effective and high-throughput method in routine prenatal clinical practice.

METHODSThe MLPA test was performed on 500 AF samples by using kit P095 and the results were obtained by using analysis software RH-MLPA-v511. The results were compared with that from fluorescence in situ hybridization (FISH) and traditional karyotyping (TK). The technical critical issues were analyzed in routine diagnostic application.

RESULTSThe absolute specificity and sensitivity of the MLPA test to detect the aneuploidy were 100%. For the 500 AF samples, the success rate of the MLPA tests was 97%. Among them 92% were finished within three working days and 5% required more days for repeating. The test failure rate was 3%. The results confirmed that for the 38 detectable aneuploid samples, the probe reliability weighted mean ratio values were more than 4SD compared to normal diploids and the 2 suspected trisomy samples were more than 2SD. In this study, authors analyzed hybridization efficiencies of 8 probes for chromosome 21, and the presence of a trisomy was considered if at least 4 of the 8 probes gave probe ratio of >1.3.

CONCLUSIONThedata suggested that MLPA is a rapid, simple and reliable method for large scale testing for aneuploidy of chromosomes 13, 18, 21, X, or Y in AF. The MLPA technology is complementary to AF culture and valuable for prenatal diagnosis.

Amniotic Fluid ; cytology ; Aneuploidy ; Chromosomes, Human, Pair 21 ; Female ; Humans ; Nucleic Acid Amplification Techniques ; methods ; Pregnancy ; Prenatal Diagnosis ; methods ; Sensitivity and Specificity ; Trisomy ; diagnosis ; genetics