Interventional treatment of central vein occlusion in maintenance hemodialysis patients / 局解手术学杂志

Objective To observe the effectiveness of the percutaneous transluminal angioplasty (PTA) and percutaneous transluminal stenting (PTS) for central vein occlusion in maintenance hemodialysis patients.Methods From January 2010 to August 2015,a total of 42 patients with center vein occlusion of arteriovenous fistula were treated with maintenance hemodialysis,and the surgery and postoperative conditions,revascularization and improvement of vascular stenosis were observed.Results Among the 42 patients,38 cases were successfully carried out with PTA,and the patency rate was 90.5%(38/42).A total of 32 intravascular stents were placed in 30 patients whose vein stenosis were still greater than 30% after PTA.After surgery,the swelling of the patient receded rapidly and the internal fistula went back to normal.Conclusion PTA and PTS are effective methods for maintenance hemodialysis patients with central vein occlusion,and they could help protecting functional access in patients with autogenous fistulas with smaller wounds and faster effects.

Diagnostic value of serum (1-3)-β-D-glucan for invasive fungal infection in neonates / 中华围产医学杂志

Objective To evaluate the diagnostic value of serum (1-3)-β-D-glucan detection for invasive fungal infection (IFI) in neonates. Methods Eighty-seven neonates who were suspected to be IFI cases in neonatal intensive care unit from May 2008 to January 2010 were enrolled into this study. All subjects had infection symptoms, while did no react to the antibiotics treatment. The diagnosis of IFI was made according to Invasive pulmonary fungal infection diagnostic criteria of children set by Subspecialty Group of Respiratory Diseases, the Society of Pediatrics, Chinese Medical Association and Invasive fungal infection diagnostic criteria for critical patients set by the Society of Critical Care Medicine, Chinese Medical Association. Circulating (1-3)-β-D-glucan levels were determined with GKT-5M set kinetic fungus detection kit. Levels of (1-3)-Β-D-glucan in IFI group and that in the control group were compared; optimal cut-off value was established with receiver operating characteristic (ROC) curve; and the sensitivity and specificity at the cut-off value of 20.0 pg/ml and optimal cut-off value were calculated and compared. Results Among the 87 suspected cases, 59 cases were not diagnosed as IFI and 28 cases were diagnosed as IFI finally. Five patients were confirmed to be IFI; seven cases were clinically diagnosed and 16 cases were still suspected IFI. Among the five confirmed cases, four cases were blood culture positive for Candida parapsilosis, one case Candida albicans positive and two cases both cerebrospinal fluid culture and blood culture positive for Candida albicans. The median levels of (1-3)-β-D-glucan of patients diagnosed as IFI (n=28) was 131.6 pg/ml(18.6-9999.0 pg/ml), which was higher than that of the patients without IFI (8.5 pg/ml, 5.0-34.6 pg/ml)(Z=-5.064, P<0.05). Area under ROC curve was 0.806 (95% CI: 0.725-0.886, P<0.05). The sensitivity (96.43% vs 69.49%) and specificity (72.22% vs 84.21%) for (1-3)-β-D-glucan were different as 20.0 pg/ml and 53.7 pg/ml were used as the cut-off values for diagnosing IFI. Conclusions (1-3)-β-D-glucan level could be used to diagnose IFI of neonates, but further studies are needed to evaluate false-positive rates and its cut-off value in IFI diagnosis.

In vitro effects of Wnt3a gene modification on mitigating damage of mouse bone marrow mesenchymal stem cells induced by Ara-C / 中国实验血液学杂志

This study was aimed to investigate the protective effect of Wit3a gene modification on mouse bone marrow mesenchymal stem cells against the injury induced by Ara-C. The gene-modified MSC steadily expressing Wnt3a were established by adenovirus system. The acute direct damage effects of different concentrations of Ara-C on the unmodified MSC and the gene-modified MSC were assessed by using an in vitro culture system, and the corresponding controls were set. The proliferation and apoptosis of MSC exposed to Ara-C were detected by cell count kit-8 (CCK-8) and flow cytometry. The expression of BCL-2 protein related with cell apoptosis was assayed by Western blot. The results indicated that as compared with unmodified MSC, Ara-C exhibited a less inhibitory effect on the proliferation of gene-modified MSC. There was obvious difference between unmodified MSC and gene-modified MSC (p < 0.05). The proliferation of gene-modified MSC began to recover at 72 hours after removal of Ara-C. However, unmodified MSC showed sustained suppression of proliferation after withdrawal of Ara-C. In apoptosis, the apoptosis rate of gene-modified MSC induced by Ara-C was significantly lower than those of unmodified MSC (p < 0.05). In addition, the expression levels of BCL-2 protein in gene-modified MSC were up-regulated compared with unmodified MSC (p < 0.05). It is concluded that Wnt3a gene modification can significantly mitigate the damage of mouse bone marrow MSC induced by Ara-C.

Effect of Wnt3a-transduced bone marrow mesenchymal stem cells on the proliferation of T lymphocytes / 中华血液学杂志

<p><b>OBJECTIVE</b>To observe the effect of Wnt3a-transduced mouse bone marrow mesenchymal stem cells (MSC) on the proliferation of T lymphocytes.</p><p><b>METHODS</b>MSC were isolated from C57BL/6 mouse bone marrow and expanded in vitro, then identified by flow cytometry and their differentiation capacity into osteocytes and adipocytes were determined. Recombinant plasmids containing Wnt3a gene, were transfected with lipofectamine into HEK293 cells by the AdEasy system. Viral particles were collected to infect MSC and adenovirus vector expressing GFP (Ad-GFP) was used as control. The expression of GFP in MSC was observed using fluorescence microscopy and the protein levels of Wnt3a and β-catenin were determined by Western blot. Wnt3a-transduced and Ad-GFP transduced MSC were separately cocultured with spleen lymphocytes stimulated by ConA, at the ratio of 1:100, 1:50 or 1:10 respectively. The proliferation rate of T lymphocytes was estimated by Cell Cout Kit-8 (CCK-8) and the level of cytokine by ELISA.</p><p><b>RESULTS</b>FCM analysis showed that the MSC were highly positive for CD90.2, CD44 and negative for CD34, CD45, they could differentiate into osteoblasts and adipocytes after induction; The titer of recombinant adenoviruses was up to 1 × 10(10) pfu/ml. After infected with the adenoviruses, MSC had the strongest GFP expression at 72 h and the efficiency of infection was 50%-60%. The expressions of Wnt3a and β-catenin protein in the Wnt3a-transduced MSC were significantly increased. MSC could suppress the proliferation of T lymphocytes in a dose-dependent manner. When MSC cocultured with spleen lymphocytes at 1:10 ratio, T lymphocyte proliferation rate and the level of IFN-γ were (55.41 ± 1.75)% and (326.70 ± 14.41) pg/ml respectively in Ad-GFP transduced MSC group, while in Wnt3a-transduced MSC group, they were (37.27 ± 2.66)% and (218.80 ± 12.93) pg/ml respectively. There was no effect on the production of IL-2.</p><p><b>CONCLUSION</b>Compared to Ad-GFP transduced MSC, Wnt3a-transduced MSC exhibit a more potent inhibitory effect on the proliferation of T lymphocytes.</p>

Site-directed mutagenesis of conserved Thr407, Asp433 and Met464 residues in small subunit of Escherichia coli gamma-glutamyltranspeptidase.

Sequence comparison showed that residues Thr407, Asp433, and Met464 in the small subunit of Escherichia coli gamma-glutamyltranspeptidase (EcGGT) were conserved in the aligned enzymes. In this study, we further investigated the functional significance of these conserved residues by site-directed mutagenesis. The wild-type and mutant enzymes were overexpressed in the recombinant E. coli M15 cells and purified to near homogeneity by Ni2+-NTA resin. Except M464L, other mutants had shown no GGT activity under enzyme assay conditions and activity staining. Furthermore, mutations on these residues impaired the capability of autocatalytic processing of the enzyme. Based on these observations, it is concluded that these residues play an important role in the enzyme maturation.

The early pathology and image study of percutaneous laser disc decompression in beagles / 介入放射学杂志

Objective To explore the cause, influencing factor and possible solving method of transient adverse reactions during the operation. Methods Sixteen healthy beagles were undergone virtual PLDD. The changes of vertebral discs and the surrounding tissues were observed by high resolution CT and MRI at different periods after the operation, and the same investigation procedure was carried out after the sacrifice of beagles. Results The beagles of the conventional vaporization group occasionally had limb tic and whining in the operations. Pieces of necrosis and edema could be found in the tissues of intervertebral foramen at the paracentetic side. The histological changes in the negative pressure suction group were less than those in the conventional group. Conclusion The reversible damages of the surrounding tissuses were observed in the conventional group and continuing negative pressure suction during the operations can prevent the damages to the surrounding tissues, all of the changes could be clearly displayed by CT and MRI scan.