Preparation and characterization of recombinant human-source collagen / 生物工程学报

This study aimed to obtain a recombinant human-source collagen for industrialization. First, based on the Gly-X-Y sequence of human type I collagen, we optimized the hydrophilic Gly-X-Y collagen peptide, designed the human collagen amino acid sequence and the corresponding nucleotide sequence. Next, the expression vector pPIC9K-COL was constructed via endonuclease digestion technology. We obtained an engineering strain of human-source collagen by electrotransforming Pichia pastoris, and then it was fermented, purified and identified. As a result, the expression level reached 4.5 g/L and the purity was over 95%. After amino acid N-terminal sequencing, molecular weight analysis, amino acid analysis and collagenase degradation test, we confirmed that the obtained collagen was consistent with designed primary structure of human-source collagen. After freeze-drying, we analyzed the collagen by scanning electron microscope and cell cytotoxicity, confirming that the collagen has porous fiber reticular structure and superior cytocompatibility. This indicates that human-source collagen has potential to be applied as biomedical material. In conclusion, we successfully obtained the expected human-source collagen and laid a foundation to its further application.

Effects of dieting and exercise intervention on lipid level in patients with hyperlipidemia / 现代临床护理

Objective To investigate the effects of dieting and exercise intervention on lipid level in patients with hyperlipidemia.Methods Health education including dieting and exercise interventions was given to 1,800 patients with hyperlipidemia.Serum total cholesterol(TC), triglyceride(TG), high density lipoprotein(HDL-C)and low density lipoprotein (LDL-C)levels were assessed before and after interventions.Result TC, TG and LDL-C levels were decreased and HDL-C increased after interventions with statistical significance(P<0.01).Conclusions Dieting and exercise intervention can be effective in controlling lipid levels effectively.Health education should vary among individuals to achieve good effects.

Diagnostic values of normalized ADC value in benign and malignant breast lesions / 实用放射学杂志

Objective To evaluate the values of DWI normalized ADC value in breast MRI in the differential diagnosis of benign and malignant breast lesions.Methods The absolute value of ADC,normalized ADC value and T1 WI dynamic contrast-enhanced TIC were analyzed in 49 patients with benign and malignant breast lesions;the efficiencies of single method diagnosis and combined diagnosis were assessed.Results When b=1 000 s/mm2 ,the absolute value of ADC <1.25×10 -3 mm2/s was taken as the thresh-old value for the diagnosis of malignant breast lesions,the area under the ROC curve was 0.818,the sensitivity was 73.9% and the specificity was 84.6%;the normalized ADC value <0.55 × 10 -3 mm2/s was taken as the diagnostic threshold,the area under the ROC curve was 0.901,the sensitivity was 87.0% and the specificity was 88.5%,there was a significant difference between both values.The lesions with a wash-out type of T1 WI dynamic contrast-enhanced TIC were diagnosed as malignant lesions,the sensitivi-ty was 89.5% and the specificity was 70.0%.The absolute value of ADC and T1 WI dynamic contrast-enhanced TIC were applied combinedly,the predicted percentage correct was 81.6% for the diagnosis of breast lesions,while the normalized ADC value and T1 WI dynamic contrast-enhanced TIC were applied combinedly,the predicted percentage correct was increased,which was 89.8%. Conclusion Normalized ADC value has a higher sensitivity and specificity in differentiating benign and malignant breast lesions,its combined application with T1 WI dynamic contrast-enhanced TIC can improve the diagnostic performance of breast lesions.

Progress of renal voltage-gated chloride channel / 国际儿科学杂志

Voltage-gated chloride channel (ClC) is a class of very important chloride ion channels in vivo,participating in the chloride ion transporter,cell volume regulation,cell control acidification and many pathological physiological process.The studies have found that ClC-K was related to dent disease,and ClC-5 was associated with bartter syndrome.This article mainly reviews ClC-type chloride ion channel classification,structure,regulation and distribution in the kidney,and summarizes the related diseases.

Multi-slice spiral CT multiplanar reconstruction findings of localized fat collection adjaction to the subdiaphragmatic inferior vena cava / 中华放射学杂志

ObjectiveTo discusses the MSCT multiplanar reconstruction manifestation (MPR) of localized fat collection adjaction to subdiaphragmatic inferior vena cava (IVCfat).MethodsThe thoracic and abdominal MSCT scan data of 8246 patients were browsed,45 patients with presumed IVCfat on axial CT scans were further studied prospectively with MSCT MPR.The predisposing position of IVCfat and its relationship with IVC were observed.It was divided into two kinds of intraluminal type and extraluminal type according to the angle of IVCfat with respect of the wall of IVC.The other 50 patients without IVCfat were randomly selected as the control group.The sagittal inclination angle (SIA) and diameter ratio (DR) between supra- and sub-diaphragmatic IVC between the two groups were compared by using t test.Results The detection rate was 0.55％ (45/8246).Of which hepatic vein lacuna 8 patients,subdiaphragmatic gap medial to IVC 28 patients and IVC groove 9 patients.The shape of IVCfat showed mainly for the round,oval and crescents on axial CT scans,of 15 patients intraluminal type,4 showed target signs .The shape of IVCfat showed mainly for half-moon at MPR.The SIA and DR at IVCfat group were 21.62° ± 8.42°and 2.01 ±0.84 respectively,at control group were 16.75° ±7.82°(t =1.594,P ＞0.05) and 1.31 ±0.28(t =2.341,P ＜ 0.05 ) respectively.ConclusionThe round,oval or half of limited fat density shadow adjaction to subdiaphragmatic inferior vena cava which similar to in the lumen is the characteristic performance of IVCfat,it may be an anatomical variation.