Calibration and quality control of medical image monitor / 医疗卫生装备

Objective To explore the standard and methods for the calibration of the medical image monitor,and to execute its quality detection.Methods The related standards and concepts of medical image monitor were analyzed,and the grayscale standard display function (GSDF) defined by DICOM was discussed.Calibration of medical image monitor was implemented with the 14th part of DICOM standard on medical image display and DICOM GSDF standard function.Results It's pointed out that lookup table and brillmeter were indispensible for DICOM GSDF calibration of medical image monitor.The calibration modes included the ones of manual,automatic and network.Conclusion Medical image monitor has to undergo calibration and quality control conventionally,and DICOM GSDF calibration should be executed before its clinical application.

Application risk and management strategy of infusion pumps / 医疗卫生装备

Objective To analyze the risk factors of the infusion pump to provide evidence-based basis for its safety management and monitoring.Methods Totally 1 000 pieces of questionnaires were issued for 100 infusion pumps from 9 grade-A tertiary hospitals in Beijing.The abnormalities and the correlation between the indexes were analyzed for the infusion pump,the indexes were compared on their effects on the abnormalities.Results Statistical analysis on data samples showed that the main factors included the manufacturer of infusion pump and pipeline,service time of infusion pump,compatibility between infusion pump and pipeline as well as the user department.Conclusion The management facility has to pose emphases on safety and utilization management as well as standardized application of the infusion pipeline so as to reduce adverse events efficiently.

A meta-analysis of carotid endarterectomy versus stenting in the treatment of symptomatic carotid stenosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Carotid stenosis is one of the common reasons for patients with ischemic stroke, and the two invasive options carotid endarterectomy (CEA) and carotid artery stenting (CAS) are the most popular treatments. But the relative efficacy and safety of the methods are not clear.</p><p><b>METHODS</b>About 521 articles related to CAS and CEA for carotid stenosis published in 1995 - 2011 were retrieved from MEDLINE, Cochrane Library (CL), and China National Knowledge Infrastructure (CNKI) China Journal Full-Test database. Of them, eight articles were chosen. Meta-analysis was used to assess the relative risks.</p><p><b>RESULTS</b>The eight studies included 3873 patients with symptomatic carotid artery stenosis, including 1941 cases in the carotid stent angioplasty group, and 1932 cases in the carotid endarterectomy group. Fixed effect model analysis showed that within 30 days of incidence of all types of strokes, surgery was significantly highly preferred in CAS patients (CAS group) than the CEA patients (CEA group), and the difference was statistically significant (relative ratio (RR) = 1.80, 95% confidence interval (CI): 1.380 - 2.401, P < 0.0001). But the incidence of death in the two groups is not showed and is not statistically significant after 30 days (RR = 1.52, 95%CI: 0.82 - 2.82, P = 0.18). The rate of cranial nerve injury in the CAS group is lower than the CEA group (RR = 0.14, 95%CI: 0.05 - 0.43, P = 0.0005). The incidence of CAS patients with myocardial infarction is lower than the CEA group after 30 days, but statistically meaningless (RR = 0.22, 95%CI: 0.05 - 1.02, P = 0.05). The stroke or death in CAS patients were higher than the CEA group after 1 year of treatment (RR = 2.58, 95%CI: 1.03 - 6.48, P = 0.04).</p><p><b>CONCLUSIONS</b>Compared to CAS, carotid endarterectomy is still the preferred treatment methodology of symptomatic carotid artery stenosis. Future meta-analyses should then be performed in long-term follow-up to support this treatment recommendation.</p>

Ion chromatography for determination of ammonia sampled by silica gel in air of workplace / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To establish an ion chromatography (IC) method for determination of ammonia in air of workplace.</p><p><b>METHODS</b>Ammonia in workplace air was collected in silica gel tube, desorbed with 10 mmol/L methanesulfonic acid by ultrasonic for 10 min, determined by IC.</p><p><b>RESULTS</b>The linearity range was 0.02-1.00 microg/ml. The linear equation was Y = 12041X-187 (r = 0.9997). The limit of quantification was 0.13 mg/m3 (the air volume was 1.5 L). Collection efficiency was 100%. Extraction efficiency was 99%. The relative standard deviation was 4.2%-6.3%. The penetration capacity was more than 264 microg. Sample could be stored for 14 days at least by ambient storage.</p><p><b>CONCLUSION</b>This method is convenient, applicable and sensitive, suitable to determinate ammonia in air of workplace.</p>

Inhibitory effect of folic acid/polyamide-amine as a miR-7 vector on the growth of glioma in mice / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore if folic acid/polyamide-amine (FA/PAMAM) enhances the therapeutic effect of miR-7gene therapy for glioma in vivo.</p><p><b>METHODS</b>The miR-7 gene was transfected into U251 glioma cells by FA/PAMAM. The efficiency of gene transfection was assessed by fluorescence microscopy. The miR-7 level was detect by quantitative RT-PCR. Intracranial glioma models were established in thymectomized mice, and FA/PAMAM nanoparticles were transplanted into the tumors in situ 3 days later. The animal survival was recorded and the gross tumor volume and degree of edema were observed by MRI. Apoptosis in the glioma cells and expression of proliferating cell nuclear antigen (PCNA), matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) were assessed by immunohistochemistry, and EGFR and AKT-2 protein expression was detected by Western blot assay.</p><p><b>RESULTS</b>Compared with the liposomes, the FA/PAMAM nanoparticles were more efficient to transfer miR-7 gene into U251 glioma cells, MRI showed that the tumor growth was much slower in the FA/PAMAM/miR-7 group, and the animal survival time was longer. The apoptosis rate was (5.3 ± 0.9)% in the control group, (11.4 ± 2.4)% in the liposome/miR-7 group, and (17.7 ± 3.7)% in the FA/PAMAM/miR-7 group. The immunohistochemical assay showed that the levels of PCNA, MMP-2 and MMP-9 protein in the FA/PAMAM/miR-7 group were (34.6 ± 5.4)%, (24.5 ± 4.1)%, (25.4 ± 5.1)%, respectively, significantly lower than those in the liposome/miR-7 group (49.3 ± 5.9)%, (31.7 ± 7.1)% and (39.4 ± 6.4)%, respectively, and those in the control group (57.3 ± 7.4)%, (45.4 ± 6.9)% and (55.1 ± 7.3)%, respectively (all P < 0.05). The expressions of EGFR and AKT-2 proteins were 1.09 ± 0.12 and 0.62 ± 0.10 in the control group, 0.63 ± 0.11 and 0.43 ± 0.07 in the liposome/miR-7 group, and significantly deceased (0.47 ± 0.09 and 0.31 ± 0.04, respectively) in the FA/PAMAM/miR-7 group (all P < 0.05).</p><p><b>CONCLUSION</b>Compared with the liposomes, FA/PAMAM can transfect miR-7 into glioma cells with a higher efficiency in vivo, makes a longer time of the drug action, and shows a certain inhibitory effect on the growth of glioma, therefore, might become a new drug targeting agent in gene therapy forglioma.</p>

Tumorigenesis of bone marrow stromal cells transplanted into the brain of Sprague-Dawley rats: Report of three cases / 肿瘤

Objective: To investigate the possible oncogenicity of bone marrow stromal stem cells (BMSCs) transplanted into brain and its underlying mechanism. Methods: The contralateral hemiplegia became gradually worse in three Sprague-Dawley rats among twenty rats after intracerebral transplantation with BMSCs. The intracerebral space occupying lesions were examined by MRI, and the life span of these rats was observed and recorded. The tumor tissues were obtained after the three rats were sacrificed. The telomerase activity was detected by telemeric repeat amplification protocol (TRAP)- PCR-enzyme-linked immunosorbent assay (ELISA). The expressions of proliferating cell nuclear antigen (PCNA), nestin and glial fibrillary acidic protein (GFAP) were detected by immunohistochemistry. The relative expression levels of epidermal growth factor receptor(EGFR), vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) proteins in intracerebral tumor tissues and normal tissues were examined by Western blotting. Results: Of twenty rats, three rats displayed left hemiplegia which was continuously getting worse, and the life spans of the three rats were 129, 174 and 187 d, respectively. The result of TRAP-PCR-ELISA showed that the telomerase activity of intracerebral tumor tissues was higher than that of intracerebral normal tissues. The expressions of PCNA and nestin proteins in intracerebral tumor tissues were both higher but the expression of GFAP was lower than those of intracerebral normal tissues. The results of Western blotting showed that among three rats with intracerebral normal tissues, the expression level of EGFR protein was increased in one rat while the expression level of VEGF protein was increased in two rats. There was no significant difference in the expression of MMP-9 protein among the three rats. Conclusion: The telomerase activity and the ability of cell proliferation of BMSCs can be enhanced and the activation of oncogenes can be observed after long-term cell culture in vitro, and these findings suggest that the tumorigenesis potential can be induced after intracerebral transplantation with MSCs. Copyright© 2011 by TUMOR.

Tropism mechanism of stem cells targeting injured brain tissues by stromal cell-derived factor-1 / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To explore the role and function of stromal cell-derived factor-1 (SDF-1) in stem cells migrating into injured brain area.</p><p><b>METHODS</b>Rat-derived nerve stem cells (NSCs) were isolated and cultured routinely. Transwell system was used to observe the migration ability of NSCs into injured nerve cells. Immunocytochemistry was used to explore the expression of chemotactic factor receptor-4 (CXCR-4) in NSCs. In vivo, we applied immunofluorescence technique to observe the migration of NSCs into injured brain area. Immunofluorescence technique and Western blotting were used to test expression level of SDF-1. After AMD3100 (a special chemical blocker) blocking CXCR-4, the migration ability of NSCs was tested in vivo and in vitro, respectively.</p><p><b>RESULTS</b>NSCs displayed specific tropism for injured nerve cells or traumatic brain area in vivo and in vitro. The expression level of SDF-1 in traumatic brain area increased remarkably and the expression level of CXCR-4 in the NSCs increased simultaneously. After AMD3100 blocking the expression of CXCR-4, the migration ability of NSCs decreased significantly both in vivo and in vitro.</p><p><b>CONCLUSIONS</b>SDF-1 may play a key role in stem cells migrating into injured brain area through specially combining with CXCR-4.</p>

Stem cells modified by brain-derived neurotrophic factor to promote stem cells differentiation into neurons and enhance neuromotor function after brain injury / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To promote stem cells differentiation into neurons and enhance neuromotor function after brain injury through brain-derived neurotrophic factor (BDNF) induction.</p><p><b>METHODS</b>Recombinant adenovirus vector was applied to the transfection of BDNF into human-derived umbilical cord mesenchymal stem cells (UCMSCs). Enzyme linked immunosorbent assay (ELISA) was used to determine the secretion phase of BDNF. The brain injury model of athymic mice induced by hydraulic pressure percussion was established for transplantation of stem cells into the edge of injury site. Nerve function scores were obtained, and the expression level of transfected and non-transfected BDNF, proportion of neuron specific enolase (NSE) and glial fibrillary acidic protein (GFAP), and the number of apoptosis cells were compared respectively.</p><p><b>RESULTS</b>The BDNF expression achieved its stabilization at a high level 72 hours after gene transfection. The mouse obtained a better score of nerve function, and the proportion of the NSE-positive cells increased significantly (P<0.05), but GFAP-positive cells decreased in BDNF-UCMSCs group compared with the other two groups (P<0.05). At the site of high expression of BDNF, the number of apoptosis cells decreased markedly.</p><p><b>CONCLUSION</b>BDNF gene can promote the differentiation of the stem cells into neurons rather than glial cells, and enhance neuromotor function after brain injury.</p>

Establishment of immortalized umbilical cord mesenchymal stem cells mediated by hTERT / 中华神经医学杂志

Objective To establish the immortalized umbilical cord mesenchymal stem cells(UCMSCs) mediated by human telomerase reverse transcriptase (hTERT) so as to offer enough UCMSCs for in vitro or clinical researches. Methods Human UCMSCs were isolated and cultured to passage 4,and then identified by flow cytometry analysis. The pLXSN-hTERT plasmid was transfected into UCMSCs by liposome to establish the immortalized UCMSCs. Expressions of hTERT mRNA and protein were respectively tested by RT-PCR and immunocytochemistry. The cell cycle kinetics of the passage of hTERT-UCMSCs and UCMSCs were detected with flow cytometry. Results Flow cytometry analysis showed that UCMSCs expressed CD29, CD44 and CD 105 strongly, but CD31, CD34 and CD45 slightly; these were right the features of human UCMSCs. RT-PCR showed that hTERT mRNA was expressed low in UCMSCs, and high in pLXSN-hTERT transfected UCMSCs.Immunocytochemistry revealed that fluorescence intensity of cell nuclei was increased significantly after transfection and that hTERT was expressed all in cell nuclei. Flow cytometry analysis suggested that the number of hTERT-UCMSCs at phase S was increased significantly, and the cells would be able to passage stably (more than 35 passages). Conclusions The immortalized UCMSCs can be established by hTERT transfection, and the number of immortalized UCMSCs can meet the need of in vitro or clinical researches.

Application of continuous monitoring of jugular venous oxygen saturation in the course of mild hypothermia treatment of severe traumatic brain injury / 中华创伤杂志

Objective To discuss significance of continuous monitoring of jugular venous oxygen saturation(S_(jv)O_2)in the course of mild hypothermia treatment(MHT)for severe traumatic brain injury (sTBI).Methods Intracranial pressure(ICP),S_(jv)O_2 and brain tissue pressure(P_(bt)O_2)were contin- uously monitored in 36 cases with sTBI for analyzing the correlation between S_(jv)O_2 and P_(bt)O_2.Results (1)There was negative linear correlation between P_(bt)O_2 and ICP(r=-0.978,P＜0.05),negative lin- ear correlation between S_(jv)O_2 and ICP(r=-0.947,P＜0.05)and positive linear correlation between P_(bt)O_2 and S_(jv)O_2(r=0.965,P＜0.05)within 24 hours and at 36 hours and 48 hours after injury.(2) The cases with decreased S_(jv)O_2 value had a worse outcome than those with normal S_(jv)O_2.meanwhile,the cases with abnormal increase of S_(jv)O_2 value had worse prognosis.Prognnsis was improved significantly with increase of S_(jv)O_2 in certain range(P＜0.05).Conclusion Continuous monitoring of S_(jv)O_2 can reflect the condition of hemicerebral oxygen metabolism and guide treatment and predicting outcome.