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Zhu F.,Stanford University | Zhu F.,Beijing University Third Hospital | Sun B.,Stanford University | Sun B.,Guangzhou University | And 5 more authors.
Stem Cells and Development | Year: 2014

Teratoma formation, the standard in vivo pluripotency assay, is also frequently used as a tumorigenicity assay. A common concern in therapeutic stem cell applications is the tumorigenicity potential of a small number of cell impurities in the final product. Estimation of this small number is hampered by the inaccurate methodology of the tumorigenicity assay. Hence, a protocol for tumorigenicity assay that can deliver a defined number of cells, without error introduced by leakage or migration of cells is needed. In this study, we tested our modified transplantation method that allows for transplant of small numbers of pluripotent stem cells (PSCs) under the kidney capsule with minimal cell leakage. A glass capillary with a finely shaped tip and an attached mouth pipette was used to inject PSCs into the rodent kidney capsule. H9 embryonic and induced PSCs were tagged with Fluc and green fluorescence protein reporter genes and divided in different cell doses for transplantation. Bioluminescence imaging (BLI) on the day of surgery showed that the cell signal was confined to the kidney and signal intensity correlated with increasing transplant cell numbers. The overall cell leakage rate was 17% and the rodent survival rate was 96%. Teratoma formation was observed in rodents transplanted with cell numbers between 1×105-2×106. We conclude that this modified procedure for transplanting PSCs under the kidney capsule allows for transplantation of a defined number of PSCs with significant reduction of error associated with cell leakage from the transplant site. © 2014, Mary Ann Liebert, Inc. Source


Xiong G.W.,Beijing University Third Hospital
Yi chuan = Hereditas / Zhongguo yi chuan xue hui bian ji | Year: 2010

To investigate distributional characteristics of mutations of HPV16 upstream regulatory region (URR) and E6 and E7 oncogene in the patients with cervical cancer in Beijing and to explore the potential association between oncogenesis of cervical cancer and HPV variants in this region, cervical cancer tissue from 31 cases with positive HPV16 were subjected to regular DNA extraction procedure. The corresponding primers were then designed to amplify the target sequence of URR, E6 and E7. The PCR products were sequenced and blast analysis against GenBank was carried out to evaluate the gene mutation and identify the phylogenetic branches. Among all the cases studied, URR was found to be the most frequent mutation fragments, followed by E7, and E6 was the most conservative sequence. A total of 8 hot mutation spot was identi-fied, which were URR G7521A (100%), C7435G (96.77%), C24T (45.16%), A7729C (45.16%), G7839A (45.16%), E6 T178G (41.94%), E7 A647G (45.16%), and T846C (45.16%). The most frequent HPV 16 branch was type As (54.84%), followed by type E (45.16%). Our results suggested that the mutations of G7521A, A7729C, G7839A, T178G, T350G, A647G, and G658A were likely to be associated with the enhanced oncogenic potential of HPV16 and oncogenesis of cer-vical cancer. In Beijing area, two major branches of HPV16 were type As and E. This finding provides valuable information for HPV vaccine development and infection treatment. Type As and E variants had different distributions among various ages and clinic stage groups. It might lead to a new explanation for the getting younger trend of cervical cancer. Source


Tang W.H.,Beijing University Third Hospital
Zhonghua nan ke xue = National journal of andrology | Year: 2013

To compare cell suspension examination with histopathology in detecting spermatozoa in the testicular tissue of non-obstructive azoospermia (NOA) patients, and to investigate the reliability of sperm retrieval and appropriate therapeutic options when the results of the two methods are inconsistent. A total of 1 112 NOA patients underwent testicular sperm extraction (TESE), their testicular tissues subjected to cell suspension examination and histopathology, respectively. The consistency rate of the two methods was 92.63%, with the sperm detection rate of 41.82% and non-sperm detection rate of 50.81%. Sperm were retrieved from 96.0% (24/25) of the patients on the day of oval retrieval, in whom sperm were found in cell suspension examination but not in histopathology. After intracytoplasmic sperm injection (ICSI), pregnancy was achieved in 8 cases (33.33%), abortion occurred in 4 (16.67%), and non-pregnancy in 12 (50.0%). Cell suspension examination combined with histopathology for detecting sperm in the testicular tissue of NOA patients gives instant, accurate, reliable and consistent results, and therefore insures successful sperm retrieval for NOA patients during the IVF cycle. In case of inconsistency between the results of the two methods, cell suspension examination is more helpful for clinical therapeutic option. Source


Objective: To identify the clinical and laboratory parameters correlating with speed of bacterial growth in culture and independent risk factors of in-hospital mortality in patients with Escherichia coli bacteremia. Methods: This retrospective study was conducted at Beijing University Third Hospital. The medical records and microbiological database of the patients diagnosed as Escherichia coli bacteremia between January 2007 and December 2009 were collected. The parameter of time to positivity (TTP) was used to be a surrogate marker of bacterial growth. Univariate analysis was used to identify relationship between clinical parameters and the speed of bacterial growth. Logistic multivariate analysis was used to identify risk factors of in-hospital mortality. Results: The medical records of 112 patients during the study period were collected, 25 patients died during hospital stay, the overall in-hospital mortality rate was 22.3%. Univariate analysis indicated the rapid-growth (TTP≤7 hours) group (n = 20) had higher incidence of neutropenia (40.0% vs. 15.2%), higher incidence of primary bacteremia (40.0% vs. 18.5%) and higher in-hospital mortality rate (45.0% vs. 17.4%) than those with slow bacterial growth (TTP>7 hours) group (n = 92, all P<0.05). The death group (n = 25) was found to have a higher incidence of TTP≤7 hours (36.0% vs. 12.6%), higher incidence of active malignancies (44.0% vs. 24.1%), higher incidence of neutropenia (36.0% vs. 14.9%), higher rate of isolation of extended spectrum β lactamases (ESBL)-producing strains (48.0% vs. 24.1%) than the survival group (n = 87, all P<0.05). Logistic multivariate analysis suggested the significant predictors of in-hospital mortality included TTP≤7 hours [odds ratio (OR) = 3.412, 95% confidence interval (95%CI) = 1.181-9.856, P = 0.023], ESBL-producing strains (OR = 2.545, 95% CI = 0.977-6.625, P = 0.056). Conclusion: In vitro Escherichia coli growth speed in the blood culture correlates with the incidence of neutropenia and primary bacteremia, and TTP≤7 hours and ESBL-producing strains may be the strong, independent risk factors of a worse prognosis in patients with Escherichia coli bacteremia. Source


Feng J.,Tianjin Medical University | He Q.-Y.,Peoples Hospital of Beijing University | Zhang X.-L.,Nanjing Medical University | Chen B.-Y.,Tianjin Medical University | And 17 more authors.
Sleep and Breathing | Year: 2012

Objective: This study seeks to determine whether scores of a short questionnaire assessing subjective daytime sleepiness (Epworth Sleepiness Scale [ESS]) are associated with blood pressure (BP) level, BP profile, and prevalence of related coronary artery disease (CAD) and cerebrovascular disease (CVD) in obstructive sleep apnea (OSA) patients diagnosed by polysomnography (PSG). Methods: Twenty university hospital sleep centers in China mainland were organized by the Chinese Medical Association to participate in this study. Between January 2004 and April 2006, 2,297 consecutive patients (aged 18-85 years; 1,981 males and 316 females) referred to these centers were recruited. BP assessments were evaluated at four time points (daytime, evening, nighttime, and morning) under standardized conditions. Anthropometric measurements, medical history of hypertension, CAD, and CVD were collected. ESS score was calculated for each participant and at the night of BP assessment, nocturnal PSG was performed and subjects were classified into four groups based on the apnea-hypopnea index (AHI) from PSG as follows: control group (control, n=213) with AHI<5; mild sleep apnea (mild, n=420) with AHI≥5 and <15; moderate sleep apnea (moderate, n=460) with AHI≥15 and <30; and severe sleep apnea (severe, n=1,204) with AHI≥30. SPSS 11.5 software package was used for the relationships between ESS and BP profile and prevalence of CAD and CVD. Results: ESS is correlated positively with average daytime, nighttime, evening, and morning BP before and even after controlling for confounding effects of age, sex, BMI, AHI, and nadir nocturnal oxygen saturation (before - r=0.182, 0.326, 0.245, and 0.329, respectively, all P values<0.001; after - r=0.069, 0.212, 0.137, and 0.208, respectively, all P values<0.001). In the severe group, nighttime, evening, morning average BPs (ABPs), the ratio of nighttime/daytime average BP (ratio of nighttime average BP to daytime average BP), and prevalence of hypertension, drug-resistant hypertension (R-HTN), isolated nighttime hypertension (IN-HTN), CAD, and CVD in excessive daytime sleepiness (EDS, ESS≥11) subjects are higher than those in non-EDS (ESS 0-10; t/χ 2=-8.388, -6.207, -8.607, -5.901, 12.742, 38.980, 16.343, 59.113, and 67.113, respectively; all P values<0.05). For EDS subjects in the moderate group but not in the control and mild group, nighttime ABP and the ratio of nighttime/daytime average BP are higher (t=-2.086 and -3.815, respectively, all P values<0.05). Linear fitting with ESS and the ratio of nighttime/daytime average BP shows a positive correlation (r 2=0.049, P<0.001). Conclusions: In severe OSA patients with comparable AHI, EDS may identify a subset of individuals with OSA at higher risk of hypertension, R-HTN, IN-HTN, CAD, and CVD. Overall, nighttime ABP seems to be more sensitive to be influenced by EDS than other ABP parameters. Future studies should investigate the potential dose-effect relationship between EDS and hypertension and the possibility that diagnosis and treatment of EDS could aid in BP reduction and ultimately in decreased morbidity and mortality from cardiovascular and cerebrovascular complications (TMUIRB20010002 at www.clinicaltrials.gov). © Springer-Verlag 2011. Source

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