Analysis of chemical constituents in ethyl acetate extract of Taxilli Herba by UPLC-Q-Exactive-MS and screening of potential xanthine oxidase inhibitors / 中国中药杂志

The present study analyzed and identified the chemical constituents from ethyl acetate(EA) extract of Taxilli Herba with UPLC-Q-Exactive-MS and screened active xanthine oxidase(XO) inhibitors with HPLC. The analysis was performed on an Hypersil GOLD C_(18) reversed-phase column(2.1 mm×50 mm, 1.9 μm), with the mobile phase of water containing 1% formic acid(A) and methanol(B) under gradient elution, the flow rate of 0.3 mL·min~(-1), and the injection volume of 5 μL. ESI source was used for MS and the compounds were collected in positive and negative ion modes. Xcalibur 4.1 was used to analyze the retention time, accurate relative molecular weight, and fragmentation of the compounds. The inhibitory activity of some known compounds on XO was screened by HPLC. Thirty chemical constituents were identified, including phenolic acids and flavonoids by experimental data combined with information of standards, data reported previously, and databases, such as MzCloud and ChemSpider. The activities of 10 chemical components were screened. Gallic acid and naringenin chalcone had strong inhibitory activities on XO with IC_(50) of 57 μg·mL~(-1) and 108 μg·mL~(-1). UPLC-Q-Exactive-MS allows the accurate, rapid, and comprehensive identification of main chemical constituents from Taxilli Herba. Gallic acid and naringenin chalcone may be the active components of XO inhibitors.

Effect of Stemona tuberosa Alkaloids on Apoptosis of SMMC-7721 Cells and Expression of Bcl-2， Bax， and Cleaved Caspase-3 / 中国实验方剂学杂志

Objective:To investigate the effect of<italic> Stemona tuberosa</italic> alkaloids on the apoptosis of human hepatoma SMMC-7721 cells and the expression of apoptosis-related proteins including B lymphocytoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and cleaved cysteinyl aspartate-specific protease-3 （cleaved Caspase-3）. Method:SMMC-7721 cells were routinely cultured， passaged， and treated with various concentrations （50， 75， 112， 167， and 250 mg·L^-1） of <italic>S. tuberosa </italic>alkaloids， while those in the blank control group were only treated with 10% fetal bovine serum. The cell proliferation was determined by tetrazolium bromide （MTT） colorimetry and colony assay and the cell apoptosis by Hoechst 33258 staining. The protein expression levels of Bcl-2， Bax， and cleaved Caspase-3 were detected by Western blot. Result:<italic>S. tuberosa</italic> alkaloids inhibited the proliferation of SMMC-7721 cells， and the inhibition rate was significantly increased in comparison with that in the blank control group （<italic>P</italic><0.01）， with the half maximal inhibitory concentrations （IC₅₀） at 24 h， 48 h， and 72 h being （173.36±8.75）， （112.14±16.50）， and （96.41±2.60）mg·L^-1， respectively. The cell colony-inhibitory activity was significantly increased in a dose-dependent manner （<italic>P</italic><0.01）. Compared with the blank control group， <italic>S. tuberosa</italic> alkaloids promoted the apoptosis of SMMC-7721 cells， manifested as increased number of apoptotic cells and elevated apoptotic rate （<italic>P</italic><0.01）. The typical morphological changes such as brightly blue-fluorescent condensed nuclei， cytoplasmic shrinking， and karyopyknosis were found under the upright fluorescence microscope. As revealed by comparison with the blank control group， the expression of Bcl-2 was significantly down-regulated （<italic>P</italic><0.01）， while the protein expression levels of pro-apoptotic protein Bax and cleaved Caspase-3 in the 75， 112， 167， and 250 mg·L^-1 <italic>S. tuberosa</italic> alkaloids groups were significantly up-regulated （<italic>P</italic><0.01）. Conclusion:<italic>S. tuberosa </italic>alkaloids inhibit the proliferation of SMMC-7721 cells and promote their apoptosis possibly by inhibiting Bcl-2 protein expression and promoting Bax and cleaved Caspase-3 protein expression.

Distinct Rab7-related Endosomal-Autophagic-Lysosomal Dysregulation Observed in Cortex and Hippocampus in APPswe/PSEN1dE9 Mouse Model of Alzheimer's Disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Amyloid-β deposition and accumulation of autophagic vacuoles are pathologic features of Alzheimer's disease (AD). Dysregulation of the endosomal-autophagic-lysosomal (EAL) pathway, which impairs amyloid precursor protein processing, is one of the earliest changes in AD. However, the precise role of EAL pathway in neurodegeneration remains unclear. This study aimed to investigate the role of EAL pathway in AD and further study the mechanism of EAL dysfunction.</p><p><b>METHODS</b>We used 3-, 7-, and 12-month-old APPswe/PSEN1dE9 (APP/PS1) mice to model different stages of AD with age- and gender-matched wild-type littermates as controls (4-7 mice per group) and detected the changes of EAL markers, endosomal organizers Rab5 and Rab7, autophagosome marker LC3B, and lysosomal proteins Lamp1/2 in cortex and hippocampus by immunohistochemistry and Western blotting analysis. To further explore the mechanism of EAL dysregulation in AD, components of the class III phosphatidylinositol 3-kinase (PI3KC3) complex, activators of Rab7 (Beclin1 and UVRAG), and the negative regulator of Rab7 (Rubicon) were also measured in this two brain regions.</p><p><b>RESULTS</b>In 7-month-old APP/PS1 brain that amyloid beta initiated to accumulate intracellularly, EAL pathway, and related PI3KC3 members, UVRAG and Beclin1 were upregulated both in cortex and hippocampus (all P < 0.05). By the age of 12 months old, when abundant amyloid plaques formed, EAL markers, UVRAG, and Beclin1 were also upregulated in the cortex (all P < 0.05). However, Rab7 was decreased significantly (P = 0.0447), accompanied by a reduction of its activating PI3KC complex component Beclin1 (P = 0.0215) and enhancement of its inhibiting component Rubicon (P = 0.0055) in the hippocampus.</p><p><b>CONCLUSIONS</b>Our study implies that EAL pathway, represented as Rab7 and its PI3KC3 regulators' expressions, showed temporal and spatial variation in brains at different stages of AD. It provides new insights into the role of EAL pathway in pathogenesis and indicates potential therapeutic targets in neurodegenerative diseases.</p>

Effects of tube size for drainage on flow rate of different kinds of fluid studied in vitro / 中华急诊医学杂志

Objective To determine the appropriate size of the tube for the thoracic drainage in good efficiency by the experimental study in the influence of the tube size on the flow rate of the fluid with different properties.Methods Three groups were divided according to the different components in the fluid:group A,whole blood with 30％ hematocrit; group B,2.5％ albumin solution; and group C,0.9％ normal saline.The total volume of the fluid was 1000 mL in each group in the experiment.Different sorts of fluids were drained with the chest tubes with different diameters (6F,8F,10F,12F,14F,16F,18F,20F,22F,24F,26F,28F,30F,32F,34F,36F of French F) separately,and the flow rate was calculated.ANOVA was used for the comparison of the differences in flow rate among the groups with given fluid property.Twofactor analysis of variance was used for the analysis of flow rates of fluid with different fluid properties.Curve fitting was performed according to the Poiseuille formula.Results The flow rate was positively correlated with the size of the chest drainage tube.The difference in flow rate among the tubes with difference in size was statistically significant (P ＜ 0.05) but there was no noticeable difference in flow rate between 6F and 8F (P =0.513).The flow rate of the 6F and 8F tubes was higher than that of the control (3.33 mL/min) but there was no significant difference between them (P ＞ 0.05).The flow rate of the tubes in 10F and above was obviously higher than that of control (P ＜ 0.05).The curve was estimated that group A was Q =0.002 9x4,R2 =0.991; group B Q=0.003 2x4,R2 =0.981; group C Q =0.003 4x4,R2 =0.975.When the flow rate was fixed at 3.33 mL/min,the estimated curve in group A was X ≈ 5.82F.Conclusions Our experiment indicated that the chest tube with small diameters (6F-14F) could meet the demand of high efficient drainage in the patients with hemothorax or pleural effusion.

Dynamic changes and its clinical significance of N-terminal pro-B-type natriuretic peptide in patients with major trauma / 中华创伤杂志

Objective To detect the dynamic change of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with major trauma and measure its relation to the outcome.Methods Sixty patients with major trauma were measured with serum NT-proBNP level at 1,3,and 7 days postinjury.According to the prognosis,the patients were allocated to survival group (n =47) and death group (n =13).Changes in NT-proBNP was detected and compared between the two groups.Correlation of NT-proBNP level with acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) and ISS was analyzed at each time point.Receiver operating characteristic curve (ROC) was developed to determine the prognostic value of NT-proBNP.Results Overall NT-proBNP level revealed no statistical difference at each time point and kept within normal reference range.NT-proBNP level in death group increased gradually,whereas in survival group the increase was followed by a reduction.Moreover,NT-proBNP level was higher in death group than in survival group at each time point.Area under the ROC of NT-proBNP had no statistical difference with that of APACHE Ⅱ and ISS at each time point.Conclusions Obviously high or continuously increased NT-proBNP level may indicate an unfavorable prognosis of major trauma patients.NT-proBNP can be used as a marker to dynamically predict prognosis of major trauma patients.

Establishment of a model of multiple trauma combined with uncontrolled hemorrhagic shock / 中华创伤杂志

Objective To establish a model of multiple trauma combined with uncontrolled hemorrhagic shock so as to provide basis for basic study of multiple trauma.Methods Forty New Zealand male rabbits were equally and randomly divided into four groups,ie,sham group (Group A,with no bloodletting or resuscitation),uncontrolled group (Group B,with bloodletting alone),aggressive fluid resuscitation and limited fluid resuscitation groups (Groups C and D,with bloodletting,hemostasis and resuscitation).Fractures of the right hind limb in rabbits of each group were induced by free drop of a 3 kg hammer from a height of 45 cm.An estimated 30％ of total blood was withdrawn from the right common carotid artery in 20 minutes in bloodletting groups (Groups B,C and D).Successively,the uncontrolled bleeding was caused via acupuncture bloodletting from ileocecal artery branch at 30 minutes in bloodletting groups.Progressive and limited fluid resuscitation using lactated Ringer' s solution (LR) were performed for Groups C and D in the next one hour respectively.Blood transfusion was performed in Groups C and D after ligation of bleeding artery branch at 90 minutes.In addition,LR of three folds more than blood loss was administered in Group D.Survivorship of rabbits in each group was observed at 150 minutes to seven hours.Arterial blood sample was taken at each time point for blood gas analysis and coagulation test.Fracture type,fluid requirements,intra-abdominal blood loss,and rabbits' survival rate at seven hours were recorded.Results Closed comminuted tibiofibular fractures were founded in all groups.Bloodletting groups showed an obvious reduction of MAP,heart rate and pH value and significantly increased levels of K+,blood glucose and lactic acid at 30 minutes (P ＜0.01),whereas MAP and heart rate were returned to baseline level at 150 minutes.Progressive fluid resuscitation significantly increased the intra-abdominal blood loss and fluid requirements (P＜0.01),decreased erythrocrit (P ＜ 0.05),prolonged prothrombin time and activated partial thromboplastin time (P ＜0.05).Survival rate of rabbits was improved significantly by fluid resuscitation at 7 hours (P ＜ 0.01).Conclusion The model is of high stability and reproducibility and therefore is fit for study of multiple trauma combined with uncontrolled hemorrhagic shock.

Significance of early detection of N-terminal pro-B-type natriuretic peptide in patients with severe trauma / 中华急诊医学杂志

ObjectiveTo detect the serum NT-proBNP level in patients with severe trauma 24 hours after injury in order to find the possible correlated factors for the evaluation of the clinical application.MethodsSixty patients with severe trauma admitted to the emergency ICU were enrolled. Serum NTproBNP level was detected 24 hours after injury for comparison between survivors and nonsurvivors. The validity of NT-proBNP for predicting outcome was analyzed by receiver operating characteristic ( ROC )curve. The factors with significant correlation between NT-proBNP level and the length of ICU stay as well as the duration of mechanical ventilation support were determined in those survivors with correlation and stepwise linear regression analysis. These factors included injury severity score (ISS), head abbreviated injury score (AIS), acute physiology and chronic health evaluation Ⅱ ( APACHE I ), Glasgow coma score (GCS), creatine kinase-MB (CK-MB), cardiac troponin-I (cTn-I) and central venous pressure. Results The median NT-proBNP levels were 762 pg/ml (IQR, 400-1131 pg/mL) in nonsurvivors versus 200 pg/ml (IQR, 80-383 pg/mL) in survivors (Z =-3. 972, P ＜0.01 ). The area under ROC curve of NTproBNP was not statistically different to that of ISS and that of APACHE Ⅱ. The best threshold value of NTproBN to predict the outcome was 384 pg/ml ( sensitivity 0. 846, specifity 0. 766). A positive correlation was found between NT-proBNP and the length of ICU stay ( r =0. 32, P ＜ 0. 05 ) as well as the duration of mechanical ventilation ( r =0. 37, P ＜ 0. 05 ) in survivors. Stepwise linear regression analysis indicated there were significant correlations between APACHE Ⅱ, CK-MB and NT-proBNP.ConclusionsSerum NT-proBNP level 24 hours after injury is correlated with the severity and outcome of patients with severe trauma. It may be used as a complementary biomarker for the rapid assessment of the severity of trauma.

Epidemical survey of glaucoma among Uigur peasants aged 40 years or above in Kuche rural / 中华实验眼科杂志

Background Glaucoma is one of the leading causes of blindness worldwide;while the different types of glaucoma is vary from different region. Objective Present study was to survey the prevalence and types of glaucoma among peasants of Uigur adults in Kuche county and offer the basis for the prevent and treatment of glaucoma in Uigur nationanlity. Methods 4191 Uigur peasants aged 40 years or above were collected in Kuche county for the survey of prevalence and types of glaucoma by randomized cluster sampling in March and April of 2009. The subjects were grouped into 40-,50-,60- and ≥70 years groups according to the distribution of age. The disease history of glaucoma, regular eye examination, funds examination and measurement of the anterior chamber depth, gonioscope were performed in the all subjects. Darkroom prone test and mydriasis test were carried out in suspicious glaucomous patients. The depth of periphery anterior chamber was assessed based on van Herick' s criteria, and the width of chamber angle was graded based on Scheie' s method. The standardized training was performed. This survey approved by Xinjiang Medical Ethics Committee, all subjects signed the informed consent before the examination. Results 4191 of 4873 subjects finished all the examinations with the response rate 86%. All the subjects showed a good compliance. The prevalence of glaucoma was 3. 79% , and the prevalence of primary angle-closed glaucoma(PACG) .primary angle-open glaucoma (PAOG) and secondary glaucoma was 2.22% ,0.26% and 1. 31% respectively, showing a significant difference among the different types of glaucoma( P<0. 05). The prevalence of glaucoma was elevated with aging (χ2 - 116. 69 ,P<0. 05) and presented a high rate in male subjects compared with female ones(χ2 = 7. 34, P<0. 05 ). Bilateral blindness was found in 19.75% glaucoma peasants, in which 25.3% glaucoma peasants received anti-glaucoma surgery. The distribution of visual acuity of patients was of significant difference among different age groups(χ2 = 37. 69 ,P<0. 05 ) . Conclusions The prevalence of the glaucoma among Uigur peasants in Kuche county was higher than most area no matter inland or overseas. PACG still is the common type in those people.

Development of a new method to measure pleural effusion volume by ultrasound in critically ill patients / 中华超声影像学杂志

Objective To develop a new method to measure pleural effusion volume by ultrasound in critically ill patients. Methods Forty-six critically ill patients admitted to emergency ICU were involved.The height of effusion (H),area of effusion at the middle section (S), thickness of effusion at middle-back line (T1) and posterior axillary line (T2) were measured by ultrasound in supine position at the end of expiration. The measured volume of pleural effusion (Vc) was calculated by H×S,and the actual volume of drainage (V) within 2 hours was also recorded. The correlation of actual volume of pleural effusion (V)with effusion height (H) ,thickness (T1, T2), area (S) and the calculated volume (Vc) were analyzed to decide the most accurate index and method. Results There was much better correlation between actual volume of effusion and S, (H & S), Vc, than these between V and T1 ,T2, H in all patients and subgroup, Vc had good correlation with V and very close to V(the average difference was 56 ml) when the actual volume was less than 500 ml,there was no difference[(417 ± 94)ml vs (402±95)ml, t = 1.095, P = 0. 285]. Both Logistic regression analysis and receiver operating characteristic (ROC) curve showed S was the most reliable index to predict the actual volume to exceed 500 ml,400 ml,and 300 ml when compared with H,S,T1 and T2. The corresponding threshold was 30.3 cm2 , 28.3 cm2 and 23. 1 cm2 , with the sensitivity and specificity of 0. 77 and 0. 88,0.72 and 1.0,0.95 and 1.0, respectively. Conclusions This new method based on measuring the area of effusion by ultrasound is more efficient and reliable than those traditional ones to measure the volume of pleural effusion. It's clinically valuable and easy to perform, and deserves broad application.

Prevalence of upper respiratory tract group A Streptococcus carriage in school-age children from Tulufan City and Buerjin County of Xinjiang Province / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the prevalence rate of upper respiratory tract group A Streptococcus (GAS) carriage in school-age children from Xinjiang Province.</p><p><b>METHODS</b>A total of 478 children at age of 9-12 years from Tulufan City and Buerjin County of Xinjiang Province were enrolled by random cluster sampling. Throat swab cultures were performed once each season for the determination of presence of GAS.</p><p><b>RESULTS</b>In the 1 827 samples, 196 GAS strains were isolated, with a GAS carrier rate of 10.7%. The prevalence rate of GAS carrier in Tulufan City ranged from 3.7%-16.5% compared with 4.7%-21.4% in Buerjin County (P < 0.05). The prevalence rate of GAS carrier in winter is the highest, followed by in autumn, spring and summer in both regions. There were significant differences in the GAS carriage rate in autumn between the two regions. There were no significant differences in the GAS carriage rate between boys and girls. Of the 196 GAS strains, 133 from Han, 22 from Uygur and 41 from Hazakh children. There were significant differences in the prevalence rate of GAS carriage among children with different ethic groups.</p><p><b>CONCLUSIONS</b>The prevalence rate of GAS carriage is high in school-age children from Tulufan and Buerjin of Xinjiang Province. The GAS carrier rate is associated with the season and ethic group. The children from Buerjin County present a higher GAS carrier rate than those from Tulufan City.</p>

Value of ultrasound in diagnosis of lung atelectasis/consolidation in multiple trauma patients with mechanical ventilation / 中华创伤杂志

Objective To evaluate the value and significance of bedside ultrasound in diagnosis of lung atelectasis/consolidation in multiple trauma patients with mechanical ventilation.Methods Bedside thoracic ultrasound and chest computed tomography(CT)were performed in 81 multiple trauma patients with mechanical ventilation admitted to the emergency intensive care unit(EICU).CT result was regarded as the "golden standard" to evaluate the value of ultrasound in diagnose lung atelectasis/consolidation.At the same time,the ultrasound was used to dynamically monitor the lung recruitment effect of the therapeutic measures.Results CT detected 154 regions of lung atelectasis/consolidation of 324 lung regions in 81 patients,while ultrasound detected 126 regions that were divided into 87 complete regions and 39 incomplete regions according to different sonogram in the breathing cycle.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of ultrasound were 81.8%,100%,100%,85.9% and 91.4% respectively.A concordance test showed a very high concordance between ultrasound and CT,with a Kappa coefficient of 0.825(P=0.031).Ultrasound found that 39 regions with incomplete lung atelectasis/consolidation were completely recruited and 62 out of 87 regions with complete lung atelectnsis/eonsolidatian gained visible recruitment within three days after different therapeutic measures,with total effective rate of 80.2%.Conclusion Bedside ultrasound can continuously monitor and guide the therapeutic measure to recruit the lung and is a convenient,safe,direct-viewing and accurate method for diagnosis of lung atelectasis/cansolidation in multiple trauma patients with mechanical ventilation.

Relationship between serum cholinesterase and acute-phase proteins in patients with multiple trauma / 中华急诊医学杂志

Objective To investigate the relationship between serum cholinesterase(ChE) and acute-phase proteins in patients with multiple trauma, then to evaluate their significance to judge prognosis. Method It's a prospective observation study. Patients with multiple trauma admitted to emergency intensive care unit,Second Af-filiated Hospital, Zhejiang Universieg, school of medicihe within 24 h after trauma from Oct. 2005 to Oct. 2007 were enrolled. And those with chronic liver disease, touching orgnaophosphorus, active tuberculosis, tumor, in-fection of major organ before trauma, liver injury or age < 18 year were excluded. Among 81 patients, 57 were male and24 female. The average age was (46±18) years, and the average injury severity score was (34.0±11.9).Seventy six healthy were selected as controls, 53 male and 23 female, with an average age of (44±16)years. The exclusion standards were the same as those in patients. Both groups had same gender proportion and age. Senum ChE and acute-phase proteins(APP) including albumin(ALB), prealbumin(PAB), transferrin(TRF),C-reactive protein(CRP) in patients were detected at 1, 3, 7 d after trauma. The acute physiology and chronic health evaluation Ⅲ (APACHEⅢ) was recorded simuhancously. Serum ChE, ALB, PAB, TRF, CRP in the controls were also detected. All of these indexes in the controls were compared with thoses in patients by t test or rank surn test. The dynamic changes of serum ChE and APPs in patients were analyzed by one way repeated mea-sures ANOVA. The relationships between serum ChE and those APPs and the relationships between APACHE Ⅲ and these indexes were analyzed by Pearson correlation analysis. We also compared these indexes between patients with different outcomes by t test or rank sum test. The values of serum ChE and those APPs to judge prognosis were evaluated by logistic regression analysis. Results Patients had lower serum ChE, ALB, PAB, TRF and higher CRP than the healthy at 1, 3, 7 d post trauma. Serum ChE activity in patients was reducod over 25% (42.3%～50.2%) than that in the healthy, and showed a tendency to decrease after trauma, which resembled PAB and TRF. Serum ChE was positively correlated with ALB, PAB and TRF at 1, 3, 7 d, and negatively correlated with CRP at 3, 7 d. At 1, 3, 7 d post trauma, APACHEⅢ in patients was negatively correlated with serum ChE and TRF, but negatively correlated with ALB only at 1 d, and negatively correlated with PAB only at 1,7 d, and posi-tively correlated with CRP only at 7 d. Non-survivors had lower serum ChE activity and TRF than survivors at 1,3,7 d after trauma, but had lower ALB only at 7 d after trauma and had lower PAB only at 1,7 d after trauma than survivors, and had higher CRP than survivors only at 7 d after trauma. Logistic regression analysis showed serum ChE and PAB were the only two independent risk factors to judge prognosis. Conclusions Serum ChE may be in-cluded as negative acute-phase protein, and is better than other APPs in reflecting injury severity and prognosis in patients with multiple trauma.

Relationship of serum insulin and peptide C levels with inflammatory reaction in patients with severe multiple trauma / 中华创伤杂志

Objective To approach the changes of serum insulin and peptide C and determine their relationship with inflammatory reaction in patients with severe multiple trauma. Methods The serum insulin, peptide C, tumor necrosis factor (TNF)-α, interleukin (IL)-10, C reactive protein (CRP) were detected in 30 patients with severe multiple trauma at days 1,3 and 7 after trauma to analyze the dynamic changes of serum insulin and peptide C and their correlations with Acute Physiology and Chronic Health Evaluation Ⅲ ( APACHE Ⅲ), cytokines and CRP. The changes of cytokines and CRP were also compared with those of serum insulin and peptide C in patients with different outcomes. The changes of serum insulin and peptide C of 35 healthy subjects were detected and used as control. Re-sults The serum insulin and peptide C levels of patients were higher than those in control group at each time point after trauma, with remarkably positive correlation with APACHE Ⅲ. Whether the serum glu-cose and age were controlled or not,serum insulin and peptide C were positively correlated with IL-10 at each time point and with TNF-α and CRP at days 3 and 7. The levels of serum insulin, peptide C and IL-10 were decreased with time in both groups with different outcomes. Meanwhile, the levels of TNF-α and CRP were decreased in the survival groups but increased in the death groups. The levels of above indices in death group were significantly higher than survival groups at the same time point. Conclusions The increasing of serum insulin and peptide C is correlated with inflammatory reaction after severe multiple trauma. The dynamic changes of both indices can either reflect injury severity or be used as an effective index in dynamically monitoring anti-inflammatory degree of the organism.

Effect of Initial Substrate Concentration on Kinetics of Hydrogen Production by Photosynthetic Bacteria in Batch Culture / 中国生物工程杂志

The effect of initial substrate concentration on the growth,metabolic activities of Photosynthetic bacteria (PSB) in the process of hydrogen production is studied.The empirical relation of the initial substrate concentration to the specific growth rate,specific substrate consumption rate and specific hydrogen production rate of PSB are developed based on the modified Monod model.It is found that the results given by the model are well agreed with the experimental data in growth phase and stationary phase of PSB.Meanwhile,the optimal substrate concentration in the process of growth,metabolism and hydrogen production is 50 mmol/L.Furthermore,when the initial substrate concentration deviates 50 mmol/L,the activation of PSB is limited or inhibited,and the inhibiting effect is more prominent than the limiting effect.In addition,it is demonstrated that initial substrate concentration has little effect on the specific substrate consumption rate.