Value of computed tomographic venography in the diagnosis of iliac vein stenosis or occlusion / 中华普通外科杂志

Objective To evaluate computed tomography venography (CTV) in diagnosis of iliac vein stenosis or occlusion.Methods From Jun 2015 to Jun 2017,168 CVD patients with CEAP clinically graded at 4 to 6 underwent evaluation with digital subtraction angiography (DSA) CTV and colour Doppler ultrasound.Taking DSA as standard,the diagnostic value of CTV and colour Doppler ultrasound were analyzed and compared.Results DSA established diagnosis of 95 cases,compared with DSA,CTV's and colour Doppler ultrasound's sensitivity,specificity,positive likelihood ratio and negative likelihood ratio was 87.4％ and 64.2％,94.5％ and 98.6％,15.89 and 45.86 and 0.13 and 0.36.Compared with colour Doppler ultrasound,CTV's sensitivity was significantly higher (P ＜ 0.05,the 95 ％ confidence intervals were 0.764-14.257),and there was no significant difference between them in aspect of specificity (P =0.375,the 95％ confidence intervals were 0.943-0.986),Kappa value was 0.809(P ＜0.05,the 95％ confidence intervals were 0.714-0.893),0.597 (P ＜ 0.05,the 95％ confidence intervals were 0.464-0.717).Conclusion In the diagnosis of CVD combined with iliac and femoral venous stenosis,CTV has outstanding sensitivity,specificity,and good conformancy with that of DSA.

Extending human hematopoietic stem cell survival in vitro with adipocytes.

Human hematopoietic stem cells (hHSCs) cannot be maintained in vitro for extended time periods because they rapidly differentiate or die. To extend in vitro culture time, researchers have made attempts to use human mesenchymal stem cells (hMSCs) to create feeder layers that mimic the stem cell niche. We have conducted an array of experiments including adipocytes in these feeder layers that inhibit hHSC differentiation and by that prolong stem cell survival in vitro. The amount of CD34(+) cells was quantified using flow cytometry. In a first experiment, feeder layers of undifferentiated hMSCs were compared with feeder layers differentiated toward osteoblasts or adipocytes using minimal medium, showing the highest survival rate where adipocytes were included. The same conclusion was drawn in a second experiment in comparing hMSCs with adipogenic feeder cells, using a culture medium supplemented with a cocktail of hHSC growth factors. In a third experiment, it was shown that direct cell-cell contact is necessary for the supportive effect of the feeder layers. In a fourth and fifth experiment the amount of adipocytes in the feeder layers were varied, and in all experiments a higher amount of adipocytes in the feeder layers showed a less rapid decay of CD34(+) cells at later time points. We therefore concluded that adipocytes assist in suppressing hHSC differentiation and aid in prolonging their survival in vitro.