1.Study on energy dissipation in modified airlift bioreactor.
Chinese Journal of Biotechnology 2005;21(5):820-825
The effects of operational variables and reactor configurations (e.g. diameter of draft tube and the number of static mixers) on energy loss in modified airlift bioreactor were investigated at the first time. The results showed that improving the structure of draft tube could reduce energy loss in the bioreactor. When the diameter of draft tube and the number of static mixers were 4.0cm and 39, respectively, the total energy loss in the modified bioreactor was the least among all the configurations and 23.6% less than that of the conventional counterpart at the same air flowrate. The energy consumption for aeration was the smallest (43.9% less than that of the conventional counterpart) when the diameter of draft tube and the number of static mixers were 5.5cm and 13, respectively. The highest energy dissipation (70% - 80%) occurred in the riser, the bottom zone (about 20%) took the second place and the separator (less than 10%) took the third place. The energy dissipation in the downcomer was neglectable under the conditions in the research. When the energy loss per unit volume was considered, bottom zone stood the first place. It was implied that the riser was the most important zone to cut down the energy loss of the bioreactor and some attention should also be paid to the bottom zone.
Bioreactors
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Equipment Design
2.Anaerobic ammonium oxidation for treatment of ammonium-rich wastewaters.
Lei ZHANG ; Ping ZHENG ; Chong-jian TANG ; Ren-cun JIN
Journal of Zhejiang University. Science. B 2008;9(5):416-426
The concept of anaerobic ammonium oxidation (ANAMMOX) is presently of great interest. The functional bacteria belonging to the Planctomycete phylum and their metabolism are investigated by microbiologists. Meanwhile, the ANAMMOX is equally valuable in treatment of ammonium-rich wastewaters. Related processes including partial nitritation-ANAMMOX and completely autotrophic nitrogen removal over nitrite (CANON) have been developed, and lab-scale experiments proved that both processes were quite feasible in engineering with appropriate control. Successful full-scale practice in the Netherlands will accelerate application of the process in future. This review introduces the microbiology and more focuses on application of the ANAMMOX process.
Bacteria, Anaerobic
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metabolism
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Bioreactors
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Nitrites
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metabolism
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Nitrogen
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metabolism
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Oxidation-Reduction
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Quaternary Ammonium Compounds
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metabolism
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Waste Disposal, Fluid
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Water Purification
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methods
3.Gas-liquid mass transfer in three-phase inverse turbulent bed reactor.
Ren-Cun JIN ; Ping ZHENG ; Jian-Wei CHEN ; Zhan TU
Chinese Journal of Biotechnology 2007;23(1):122-126
The characteristics of gas-liquid mass transfer of three-phase system comprising air, tap water/wastewater, and hollow glass beads were studied in a laboratory-scale inverse turbulent bed reactor. The influence of operational factors and liquid property on volumetric liquid-phase mass transfer coefficient kLa was investigated under the conditions of superficial gas velocity (0.53mm xs(-1) - 10mx s(-1) solid hold-up (0 - 0.3), and superficial liquid velocity (0 - 0.2mm x s(-1)). The results showed that the coefficient value was 0.0456 - 1. 414min -, which increased with superficial gas velocity and liquid velocity. The coefficient attained the maximum value at solid hold-up of 0.05 - 0.08. Compared with the coefficient value in tap water, that in synthetic wastewater and industrial wastewater is decreased by 39.0% and 50.9%, respectively. These data have provided a basis for the process analysis and mathematical simulation of inverse turbulent bed reactor.
Algorithms
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Biodegradation, Environmental
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Bioreactors
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Computer Simulation
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Gases
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chemistry
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metabolism
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Kinetics
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Models, Chemical
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Reproducibility of Results
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Temperature
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Waste Disposal, Fluid
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instrumentation
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methods
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Water
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chemistry
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metabolism
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Water Microbiology
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Water Pollutants, Chemical
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chemistry
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metabolism
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Water Purification
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instrumentation
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methods
4.Effect of Wnt signaling suppression on gefitinib in non small cell lung cancer cell lines.
Xia FANG ; Pan GU ; Cai-cun ZHOU ; Sheng-xiang REN ; Ben-fang LUO ; Yu ZENG ; Yun-jin WU ; Yin-min ZHAO ; Xu-you ZHU ; Xiang-hua YI
Chinese Journal of Pathology 2013;42(7):455-459
OBJECTIVETo explore the effect of Wnt signaling suppression on proliferation of non small cell lung cancer to gefitinib, and its related mechanisms.
METHODSPC9 and PC9/AB2 cells of both gefitinib sensitive and resistant were treated with different concentrations of gefitinib, and the proliferation index was measured using CCK8 kit. The members of Wnt signaling pathway were detected by Western blot. Dual luciferase reportor gene assay (TOP Flash) was used to document the transcriptional level of β-catenin. β-catenin siRNA was transfected into PC9/AB2 cells to suppress the Wnt signaling transcription, followed by treatment with different concentrations of gefitinib. Western blot was then used to detect the expression of EGFR and its downstream signaling after inhibit the expression of β-catenin.
RESULTSTreating with different concentrations of gefitinib, the resistance of PC9/AB2 cells to gefitinib was significantly increased (P < 0.05). The members of Wnt signaling expressed at higher level in PC9/AB2 cells than in PC9 cells (t = 24.590, P = 0.000). TOP Flash examination showed that the endogenous transcriptional activity of Wnt signaling was higher in PC9/AB2 cell than that in PC9 cell (t = 4.983, P = 0.008). Compared with the negative control group, apoptotic rate and sensitivity to gefitinib significantly increased in interfered group (P < 0.05). The expression of p-ERK1/2 significantly decreased after Wnt signaling suppression, although other proteins showed no significant alterations.
CONCLUSIONSuppressing the activity of Wnt signaling can partly reverse the celluar resistance to gefitinib in non small cell lung cancer.
Antineoplastic Agents ; administration & dosage ; pharmacology ; Apoptosis ; Carcinoma, Non-Small-Cell Lung ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Dose-Response Relationship, Drug ; Drug Resistance, Neoplasm ; Humans ; Lung Neoplasms ; metabolism ; pathology ; Mitogen-Activated Protein Kinase 1 ; metabolism ; Mitogen-Activated Protein Kinase 3 ; metabolism ; Phosphorylation ; Quinazolines ; administration & dosage ; pharmacology ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism
5.Kv1.3 potassium channel expression changes after CD4(+) and subsets CD28(null)/CD28(+)T cells activation in peripheral blood of patients with acute coronary syndrome.
Da-ying FENG ; Cun-tai ZHANG ; Ye-xin MA ; Hong-lian ZHOU ; Ren-de XU ; Xin-wei YANG ; Shen HUANG ; Jin MA ; Xiao-qing QUAN
Chinese Journal of Cardiology 2009;37(7):599-604
OBJECTIVETo study the Kv1.3 channel expression changes after CD4(+) and subsets CD28(null)/CD28(+)T cells activation in peripheral blood of patients with acute coronary syndrome (ACS).
METHODSCD4(+)T cell in 27 ACS patients and CD4(+)CD28(null)/CD4(+)CD28(+)T cells in 12 out of these 27 ACS patients were isolated from peripheral blood with magnetic cell sorting. The whole-cell Kv1.3 currents for three T cells were recorded with patch-clamp technique before and 72 hours after activation by purified anti-human CD3 Interferon gamma, tumor necrosis factor alpha (TNF-alpha), granzyme B mRNA expression were determined by reverse transcription-PCR before and 72 hours after activation by purified anti-human CD3 in the presence or absence of recombinant Margatoxin (rMgTX, 0.1, 1, 10 nmol/L), a specific Kv1.3 channel blocker.
RESULTSPeak Kv1.3 channel currents of CD4(+), CD4(+)CD28(null), CD4(+)CD28(+)T cells were significantly increased and the mean Kv1.3 channel numbers per cell of these cells were increased by about 90%, 60%, 80% (402 +/- 88 vs. 752 +/- 275, 553 +/- 328 vs. 874 +/- 400, 392 +/- 133 vs. 716 +/- 251, all P < 0.05) after activation compared to baseline values. Baseline CD4(+)CD28(null)T cell numbers were about 40% more than those of CD4(+)CD28(+)T cell (P < 0.05) and were similar after activation (P = 0.102). The mRNA expression of interferon gamma, TNF-alpha and granzyme B were dose-dependently down-regulated by rMgTX.
CONCLUSIONSKv1.3 channels of peripheral CD4(+)T cell and CD28(null)/CD28(+)T cells from ACS patients significantly increased after activation and Kv1.3-specific channel blocker rMgTX could effectively abolish this effect suggesting a potential role of Kv1.3 channel blocker on plaque stabilization in ACS patients.
Acute Coronary Syndrome ; blood ; metabolism ; CD28 Antigens ; metabolism ; CD4-Positive T-Lymphocytes ; metabolism ; Female ; Humans ; Kv1.3 Potassium Channel ; metabolism ; Lymphocyte Activation ; Male ; Middle Aged ; Patch-Clamp Techniques ; T-Lymphocyte Subsets ; metabolism
6.Clinical features of unexpected sudden death clustered in 7 families in Yunnan Province.
Jian ZHANG ; Guo-qing SHI ; Wen-li HUANG ; Jian-zhong BAO ; Shao-dong YE ; Jin-ma REN ; Zhao-xiang LI ; Meng-yue YU ; Xin GAO ; Yue-bing WANG ; Tong LUO ; Chong-jian LI ; Lin YANG ; Xiao-qing REN ; Su ZHAO ; Lai-feng SONG ; Cun-long NIU ; Hong-yue WANG ; Hong ZHAO ; Robert E FOUNTAINE ; Chong-fu YANG ; Jie-lin PU ; Yue-jin YANG ; Guang ZENG
Chinese Journal of Cardiology 2008;36(7):613-617
OBJECTIVETo investigate the clinical features of unexpected sudden death (SUD) clustered in families in Yunnan province.
METHODSThis retrospective study analyzed the clinical features of SUD occurred between July to September 2005 in 7 families in Yunnan province.
RESULTSAll 16 SUD patients shared common clinical features such as fatigue and repeated syncope and one group of SUD patients (n = 8 from 4 families) presented with the gastric intestinal tract manifestations including nausea, vomiting, abdominal pain and diarrhea with suspected dietary history and abnormal laboratory enzyme findings (GOT/GPT, CK/CKMB, LDH/LDH1 etc.). In SUD patients without gastric intestinal tract manifestations (n = 8 from 3 families), there were no clear symptoms before death and repeated ventricular tachycardia and ventricular fibrillation were recorded in one survivor. There was no clear evidence for the involvements of hereditary and infectious factors for observed SUD.
CONCLUSIONThe reason for the unexpected sudden death clustered in 7 families in Yunnan remains unclear. Repeated syncope and fatigue served as the common clinical features in the presence or absence of gastric intestinal tract manifestations in all SUD cases. Further studies are needed to clarify the pathology and detailed clinical manifestations of SUD occurred in this area.
Adolescent ; Adult ; Bias ; Cause of Death ; Child ; China ; epidemiology ; Death, Sudden ; epidemiology ; Family ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Young Adult
7.Study on the genotyping and microevolution of Yersinia pestis in the Qinghai-Tibet Plateau.
Min LI ; Er-hei DAI ; Rui-xia DAI ; Dong-sheng ZHOU ; Xiao-yan YANG ; Bai-zhong CUI ; Li-xia JIN ; Hai-hong ZHAO ; Cun-xiang LI ; Mei-ying QI ; Dun-zhu Ci REN ; Xiang DAI ; Yong-jiao TANG ; Rui-fu YANG
Chinese Journal of Epidemiology 2006;27(5):412-415
OBJECTIVETo study the distribution of genomovars and microevolution of Yersinia pestis in the Qinghai-Tibet Plateau.
METHODSPrimer pairs targeting the twenty-two different regions(DFRs) were designed for detecting the presence or deletion of each DFR in 297 strains isolated from the Qinghai-Tibet Plateau.
RESULTS9 genomovars, i. e. Genomovar 1, 5, 6, 7, 8, 10, 11, new type and Ype-ancestor were identified in the Marmota himalayana plague focus of the Qinghai-Tibet Plateau. Among these genomovars, genomovar 5,8 and 10 were dominant types. The total rate of the three genomovars was 80.6% (204/253) and the genomovars in different regions were different. All of 44 strains of Y. pestis in the Microtus fuscus plague focus of the Qinghai-Tibet Plateau belonged to genomovar 14.
CONCLUSIONThe distribution of genomovars of Y. pestis in the Qinghai-Tibet plateau had remarkable characteristics geographically. Based on the distribution of genomovars of Y. pestis, the routes of transmission and microevolution of Y. pestis were proposed.
Biological Evolution ; China ; Geography ; Humans ; Plague ; transmission ; Yersinia pestis ; genetics
8.Mechanisms of improvement of left ventricle remodeling by trans-planting two kinds of autologous bone marrow stem cells in pigs.
Shu-ren LI ; Xiao-yong QI ; Fu-li HU ; Jian-qing ZHANG ; Tian-hong WANG ; Yi DANG ; Cun-liang MENG ; Hui-liang LIU ; Ying-xiao LI ; Di WU ; Jie DONG ; Li-ying XUN ; Li-hui GAO ; Fu-chang JIN
Chinese Medical Journal 2008;121(23):2403-2409
BACKGROUNDThe necrosis of a large number of myocardial cells after acute myocardial infarction (AMI) results in a decrease of cardiac function and ventricle remodeling. Stem cell transplantation could improve cardiac function after AMI, but the involving mechanisms have not been completely understood. The present study aimed to investigate the effects of transplantation of autologous bone marrow mononuclear cells (BM-MNC) and mesenchymal stem cells (MSCs) via the coronary artery on the ventricle remodeling after AMI as well as the mechanisms of the effects of transplantation of different stem cells on ventricle remodeling.
METHODSA total of 36 male pigs were enrolled in this study, which were divided into 4 groups: control group, simple infarct model group, BM-MNC transplantation group, and MSCs transplantation group. At 90 minutes when a miniature porcine model with AMI was established, transplantation of autologous BM-MNC ((4.7 +/- 1.7) x 10(7)) and MSCs ((6.2 +/- 1.6) x 10(5)) was performed in the coronary artery via a catheter. Ultrasound, electron microscope, immunohistochemical examination and real time reverse transcriptase-polymerase chain reaction were used respectively to observe cardiac functions, counts of blood vessels of cardiac muscle, cardiac muscle nuclear factor (NF)-kappaB, myocardial cell apoptosis, and the expression of the mRNA of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in cardiac muscles. Multivariate Logistic regression was used to analyze the correlation factors of left ventricular end-diastolic diameter (EDD).
RESULTSThe number of blood vessels in the infarct zone and around its border in the BM-MNC transplantation group was more than those in the infarct model group and MSCs group (P = 0.0001) and there was less myocardial cell apoptosis in the stem cell transplantation group than that in the infarct model group (all P < 0.01). The positive rate of NF-kappaB in the stem cell transplantation group was lower than that in the infarct model group (P = 0.001). The gene expression of VEGF in the infarct border zone of the BM-MNC group was higher than that in the MSCs group (P = 0.0001). The gene expression of bFGF in the infarct border zone in the MSCs transplantation group was higher than that in the infarct model group and the BM-MNC group (P = 0.0001). Left ventricular ejection fraction was inversely proportional to the apoptotic rate of myocardial cells and cardiac muscle NF-kappaB but positively correlated with the number of blood vessels and the expression of VEGF and bFGF in the infarct zone and infarct border zone. The Multivariate Logistic regression analysis on the factors influencing the left ventricular end-diastolic diameter after stem cell transplantation showed that the expression of VEGF mRNA in the cardiac muscles in the infarct zone, the number of apoptotic myocardial cells and the expression of NF-kappaB in the infarct border zone were independent factors for predicting the inhibitory effect on the dilation of left ventricular EDD after stem cell transplantation.
CONCLUSIONSTransplantation of autologous BM-MNC and MSCs in pigs can improve the condition of left ventricular remodeling and recover the cardiac functions after AMI. The improvement of cardiac functions is related to the increase of blood vessels, the increased expression of VEGF and bFGF, the reduction of myocardial cell apoptosis, and the decrease of NF-kappaB level in cardiac muscle tissues after stem cell transplantation.
Animals ; Bone Marrow Transplantation ; methods ; Disease Models, Animal ; Heart Function Tests ; Male ; Myocardial Infarction ; physiopathology ; surgery ; Stem Cell Transplantation ; methods ; Swine ; Treatment Outcome ; Ventricular Remodeling
9.Treatment of super obesity by laparoscopic Roux-en-Y gastric bypass: experience of 42 cases.
Jing-ge YANG ; Cun-chuan WANG ; You-zhu HU ; Jin-yi LI ; Jing HUANG ; Yun-long PAN ; Hua YANG ; Jun-liang GAN ; Wan-ling LIU ; Guo CAO ; Zhi-lun LI ; Ning REN
Chinese Journal of Gastrointestinal Surgery 2012;15(11):1115-1119
OBJECTIVETo investigate the feasibility and efficacy of laparoscopic Roux-en-Y gastric bypass(LRYGB) for super obesity(BMI≥50 kg/m(2)).
METHODClinical data of 42 patients undergoing LRYGB in the First Affiliated Hospital of Jinan University between 2004 and 2008 were analyzed retrospectively.
RESULTSAll the LRYGB procedures were successfully performed with no conversion to open surgery. Average operation time was 145.1 minutes, volume of blood loss during the surgery was 25.0 ml, and length of postoperative hospital stay was 9.9 days. The cases were followed up for 1 month to 30 months. Body weight and BMI decreased significantly 1 month after the operation and reached a minimum level after 2 years then became stable while excess body weight loss rate(EWL) increased(P<0.05). All the obese-related symptoms were relieved significantly. Four cases(9.5%) showed complications during perioperative period including 1 case of respiratory failure, 2 cases of gastrojejunal anastomotic bleeding, 1 case of umbilical wound infection, and 11 developed long-term complications. All of them were cured by conservative treatment.
CONCLUSIONSTreatment of super obesity by LRYGB is feasible with significant short-term results. But due to the difficulty of the operation and postoperative complications, comprehensive treatment from experienced bariatric surgical team is needed. The long-term outcome needs for further observation.
Adolescent ; Adult ; Female ; Gastric Bypass ; methods ; Humans ; Laparoscopy ; Male ; Middle Aged ; Obesity, Morbid ; surgery ; Retrospective Studies ; Treatment Outcome ; Young Adult
10.Study on incidence of HIV infection among heroin addicts receiving methadone maintenance treatment in Dehong prefecture, Yunnan province
Song DUAN ; Yue-Cheng YANG ; Jing HAN ; Shun-Sheng YANG ; Ying-Bo YANG ; Yu-Cun LONG ; Guo-Qiang LI ; Jin-Song YIN ; Li-Fen XIANG ; Run-Hua YE ; Jie GAO ; Ren-Hai TANG ; Lin PANG ; Ke-Ming ROU ; Zun-You WU ; Na HE
Chinese Journal of Epidemiology 2011;32(12):1227-1231
Objective To determine the incidence and risk factors of HIV infection among heroin addicts receiving methadone maintenance treatment(MMT)in Dehong prefecture,Yunnan province.Methods All heroin addicts who were HIV negative at the initiation of MMT in June 2005 and through June 2011,in Dehong prefecture were included in the cohort analysis.HIV incidence was calculated and related risk factors determined by using Cox proportional hazard regression model.Results A total of 3154 MMT clinic attendants were qualified for this cohort study.By June 2011,1023(32.4%)of them had never received any follow-up HIV testing so were thus referred as loss to follow-up.The other 2131(67.6%)members had received at least one follow-up HIV testing and were observed for a total of 4615.86 person-years.During the period,22 new HIV infections or seroconverters were identified,making the overall HIV incidence as 0.48/100 person-years.The HIV incidence was higher among those who were unemployed,never married,self-reported being injecting drug users(IDUs)and HCV positive at entry into the MMT program.None of those who were always negative on follow-up-urine-testing of morphine was discovered as HIV newly infected during the follow-up period.Data from multiple regression analysis under Cox proportional hazard model indicated that after controlling for confounding variables,non-IDUs at the entry point for the MMT program,were less likely to be HIV newly-infected or seroconverted than IDUs(HR=0.29,95%CI:0.11-0.76).Conclusion MMT prograqm in Dehong prefecture was demonstrated to be fairly effective in reducing HIV transmission through drug use.Those HIV negative attendants at the MMT clinic who were IDUs or keep using drugs during the treatment,were at higher risk of HIV seroconvertion.More efforts were needed to improve the follow-up and HIV testing programs for the MMT clinic attendants.