Discussion on Microbial Quality Control Strategy in Whole Process of Chinese Materia Medica Production Guided by Concept of QbD / 中国实验方剂学杂志

Safety is the core of the quality of Chinese materia medica products， and microbial pollution caused by medicinal materials， decoction pieces， intermediate products and others can bring certain impact on the quality and safety of Chinese materia medica products. The reasons for this are not only the problems of medicinal materials themselves， but also the exogenous pollution introduced in the production process. How to effectively use microbial detection technology and establish an appropriate microbial quality control strategy in the whole process of Chinese materia medica production is of great significance to improve the quality of Chinese materia medica products. Therefore， the authors put forward a microbial quality control strategy in the whole process of Chinese materia medica production based on the guidance of quality by design （QbD） concept， emphasizing the scientific linkage between the internal and external microbial quality control systems to jointly ensure the quality of products in all aspects. Among them， the internal microbial quality control system includes the control of the whole chain of Chinese materia medica-decoction pieces-intermediate products-excipitents-packaging materials-final products， which should be carried out by stages and characteristics， while the external microbial quality control system includes the control of personnel-equipment and facilities-pharmaceutical water-environment， emphasizing the principle of quality risk management and the development of monitoring programs， aiming to closely integrate microbial quality risk management with the production process of Chinese materia medica products， and to classify and develop microbial control strategies in order to minimize the impact of contaminating microorganisms and effectively guarantee the quality of Chinese materia medica products.

Trimethylamine oxide induces pyroptosis of vascular endothelial cells through ALDH2/ROS/NLRP3/GSDMD pathway / 中南大学学报(医学版)

Objective: Trimethylamine oxide (TMAO) is a metabolite of intestinal flora and is known to promote the progression of atherosclerotic plaques. However, how TMAO works, including its effect on vascular endothelial cells, is not fully understood. This study aims to explore the biological role of TMAO in human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. Methods: Cell pyroptosis and the loss of plasma membrane integrity were induced under TMAO stimulation in HUVECs. The plasma membrane integrity of the cells was measured by Hoechst 33342/propidium iodide (PI) staining and lactate dehydrogenase leakage assay, and the changes in cell morphology were observed by atomic force microscope. The expression of proteins related to pyroptosis was determined by Western blotting or immunofluorescence. Mitochondrial acetaldehyde dehydrogenase 2 (ALDH2) activity in HUVECs was measured by the ALDH2 activity assay kit, and the level of reactive oxygen species (ROS) was detected by fluorescent probe DCFH-DA. Results: TMAO induced pyroptotic cell death, manifesting by the presence of propidium iodide-positive cells, the leakage of lactate dehydrogenase, the production of N-terminal gasdermin D (GSDMD-N), and the formation of plasma membrane pores. Moreover, TMAO induced elevated expression of inflammasome components, nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3),apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), and caspase-1 in cells. TMAO significantly inhibited ALDH2 activity and increased intracellular ROS production. However, the activation of ALDH2 by pharmacological manipulation attenuated TMAO-induced inflammasome activation and GSDMD-N production.Conclusion: TMAO induces pyroptosis of vascular endothelial cells through the ALDH2/ROS/NLRP3/GSDMD signaling pathway, which may be a potential therapeutic target for improving the treatment of atherosclerosis.

Primary Study on Predicting the Termination of Paroxysmal Atrial Fibrillation Based on a Novel RdR RR Intervals Scatter Plot / 生物医学工程学杂志

Predicting the termination of paroxysmal atrial fibrillation (AF) may provide a signal to decide whether there is a need to intervene the AF timely. We proposed a novel RdR RR intervals scatter plot in our study. The abscissa of the RdR scatter plot was set to RR intervals and the ordinate was set as the difference between successive RR intervals. The RdR scatter plot includes information of RR intervals and difference between successive RR intervals, which captures more heart rate variability (HRV) information. By RdR scatter plot analysis of one minute RR intervals for 50 segments with non-terminating AF and immediately terminating AF, it was found that the points in RdR scatter plot of non-terminating AF were more decentralized than the ones of immediately terminating AF. By dividing the RdR scatter plot into uniform grids and counting the number of non-empty grids, non-terminating AF and immediately terminating AF segments were differentiated. By utilizing 49 RR intervals, for 20 segments of learning set, 17 segments were correctly detected, and for 30 segments of test set, 20 segments were detected. While utilizing 66 RR intervals, for 18 segments of learning set, 16 segments were correctly detected, and for 28 segments of test set, 20 segments were detected. The results demonstrated that during the last one minute before the termination of paroxysmal AF, the variance of the RR intervals and the difference of the neighboring two RR intervals became smaller. The termination of paroxysmal AF could be successfully predicted by utilizing the RdR scatter plot, while the predicting accuracy should be further improved.

Curcumin inhibits LPS-induced EMT through down-regulating NF-κB-Snail signaling in breast cancer cells / 西安交通大学学报(医学版)

Objective To investigate whether epithelial-mesenchymal transition (EMT)is involved in the anti-invasion and anti-metastasis effects of curcumin on MDA-MB-2 3 1 breast cancer cell line and further analyze the underlying mechanisms.Methods MTT method was used to detect the anti-proliferative effect of curcumin on MDA-MB-2 3 1 cell line induced by lipopolysaccharide (LPS).The morphological changes were determined by optical and transmission electron microscopy,respectively.The expressions of Vimentin,E-cadherin,NF-κB and Snail were analyzed using RT-PCR and Western blotting.Results Curcumin could inhibit the occurrence of LPS-induced EMT of MDA-MB-2 3 1 breast cancer cell line, decrease the expression of LPS-induced EMT marker Vimentin and increase the expression of E-cadherin, resulting in the inhibition of in vitro cell motility and invasiveness.These actions were mediated by inactivating NF-κB-Snail signaling pathways.Conclusion Our data provide a new perspective of the anti-invasion mechanism of curcumin,indicating that the effect is in part due to its ability to inhibit the EMT process.

Inhibitory effect of colchicine on transforming growth factor β1/Smads pathway in rat models of chronic pancreatitis / 中国组织工程研究

BACKGROUND:Pancreatic stelate cels transforming growth factor β1/Smads signaling pathway activation is probably a main molecular mechanism of pancreatic fibrosis. If this pathway can be blocked, the progression of fibrosis of tissues with chronic pancreatitis wil be inhibited. OBJECTIVE:To study the inhibitory effect of colchicine on transforming growth factor β1/Smads pathway in chronic pancreatitis rat models. METHODS:Healthy male Sprague-Dawley rats were randomly divided into colchicines-treated group and chronic pancreatitis group. After successful establishment of rat models of chronic pancreatitis, the rats in the colchicines-treated group were intraperitonealy injected with colchicine 150 μg/kg daily. The rats in the chronic pancreatitis group were intraperitonealy injected with equal volume of physiological saline daily. Pancreatic tissues were colected after 3 months. Hematoxylin-eosin staining was used to observe histopathological changes of pancreatic tissue. Immunohistochemical staining was used to detect the expressions of transforming growth factor β1 in pancreatic tissue. Western blot assay was utilized to detect the expressions of P-Smad2, P-Smad3 and α-SMA protein in pancreatic stelate cels. RESULTS AND CONCLUSION: Hematoxylin-eosin staining results revealed that compared with the colchicines-treated group, glandular tissue had reduced, while fibrous connective tissue and inflammatory cels had increased obviously and replaced the pancreatic gland tissue in the chronic pancreatitis group. Immunohistochemical staining results demonstrated that the expression levels of transforming growth factor β1 and the index of positive cels were significantly lower in the colchicines-treated group than those in the chronic pancreatitis group (P < 0.05). Western blot assay results revealed that the results of P-Smad2/β-actin, P-Smad3/β-actin andα-SMA/β-actin in pancreatic stelate cels were significantly lower in the chronic pancreatitis group than those in the colchicines-treated group (P < 0.05). Results suggested that colchicine could inhibit the activity of transforming growth factor β1/Smads pathway and pancreatic tissue fibrosis in chronic pancreatitis rats. Therefore, colchicine can be used as a new candidate therapeutic scheme for chronic pancreatitis fibrosis.

Study of the RNA secondary structure prediction / 生物医学工程学杂志

This paper proposes algorithm in predicting the RNA secondary structure that combines several sequence comparisons, searches the eigenvalue for subsequence division with dynamic programing, utilizing the minimum free energy method. Moreover, the paper assesses the results derived from this new algorithm based on base-pairs distance, climbing distance and morphology distance. The paper also compares the assessment result and the prediction results of different prediction tools, and analyzes the advantages of the new method and its improvement direction.

Heart rate variability study based on a novel RdR RR Intervals Scatter Plot / 生物医学工程学杂志

On the basis of Poincare scatter plot and first order difference scatter plot, a novel heart rate variability (HRV) analysis method based on scatter plots of RR intervals and first order difference of RR intervals (namely, RdR) was proposed. The abscissa of the RdR scatter plot, the x-axis, is RR intervals and the ordinate, y-axis, is the difference between successive RR intervals. The RdR scatter plot includes the information of RR intervals and the difference between successive RR intervals, which captures more HRV information. By RdR scatter plot analysis of some records of MIT-BIH arrhythmias database, we found that the scatter plot of uncoupled premature ventricular contraction (PVC), coupled ventricular bigeminy and ventricular trigeminy PVC had specific graphic characteristics. The RdR scatter plot method has higher detecting performance than the Poincare scatter plot method, and simpler and more intuitive than the first order difference method.

The rat model of graft cholangiopathies established by cold preservation or chronic rejection / 中华肝胆外科杂志

Objective To develop rat models of graft cholangiopathies and evaluated their values.Methods Four groups were constructed.The long-term cold preservation group(n=24) contained homogeneic inbred rat liver orthotopic transplantations (ROLT) performed in a rat combination of ♂ Wistar→ ♂ Wistar with the donor liver preserved in 4℃ UW for 12 h,the vessels reconstructed by the two-cuff method,and the hepatic artery and extrahepatic bile duct rebuilt by a stent.The chronic rejection group (n=24)(CsA 1 mg · kg-1 · d-1,cold preserved for 1 h) was allogeneic inbred ♂ DA→♂ Lewis rats induced for ROLT,and the revascularization methods were the same as the longterm cold preservation group.The control group (n=24) (cold preserved for 1 h) was homogeneic inbred ♂ Wistar→♂ Wistar rats with ROLT techniques the same as above.The sham group (n=24)was ♂ Wistar rats that had an exploratory laparotomy.The animals were followed for 16 weeks,complications were compared,and liver tissues were harvested.Histopathological and morphometric techniques were used to construct a time course of histological changes after liver transplantation.Results In both the long-term cold preservation group and chronic rejection group,the rats recovered slowly,the incidence of complications and mortality were higher than those of other groups,and the intrahepatic bile duct proliferation and immune cell infiltration were noticeable after the operation.In 16 weeks,the hepatic lobules were separated by the proliferating bile ducts,the normal structure of hepatic lobules disappeared,many biliary epithelial cells necrosed with disappearing cytoplasms,and there was immune cell infiltration and obliterative arteriopathy.Conclusions The rat models of graft cholangiopathies induced by long-term cold preservation or chronic rejection donor livers are stable and easily standardized.This model is ideal for studying the pathogenesis and prevention of graft cholangiopathies.

Regulation of mTOR signal pathway in HeLa cells under different nutritional conditions by Coxsackie virus B3 / 中南大学学报(医学版)

OBJECTIVE@#To explore the changes of mTOR signal pathway in HeLa cells under different nutritional conditions infected with Coxsackie virus B3 (CVB3).@*METHODS@#The HeLa cells were cultured with two methods: the conventional culture method cultured HeLa cells with medium with 10% fetal bovine serum for 24 h and changed the medium next day, and then infected with CVB3; the serum starvation method cultured HeLa cells with medium without fetal bovine serum for 24 h, and then infected with CVB3. The expression of the coat protein of CVB3, mTOR, p70S6K mRNA was detected with RT-PCR at different time points.@*RESULTS@#The virus group showed the expressions of mTOR and p70S6K mRNA were significantly higher than those in the control group at 12 h and 24 h (P0.05).@*CONCLUSION@#CVB3 can down-regulate the expressions of mTOR and p70S6K mRNA. The mTOR expression in the starvation serum is higher than that in the conventional culture.

Construction of RNAi targeting TRAF1 gene and effect of TRAF1 on gastric cancer cells / 中南大学学报(医学版)

OBJECTIVE@#To construct the RNAi targeting tumor necrosis factor receptor associated factor (TRAF1) gene, and to explore the effect of interference targeting TRAF1 on the biological behavior of gastric cancer cells.@*METHODS@#We detected the expression of TRAF1 in BGC823, SGC7901, and MGC803 gastric cancer cell lines through the real-time PCR and Western blot; then we constructed three pLVXshRNA- TRAF1-shRNAs expression vector targeting TRAF1. When TRAF1 was interfered successfully, we selected the strongest interference efficiency ShRNA by real-time PCR and Western blot. Based on interference targeting TRAF1 on gastric cancer, we tested the cell proliferation activity and apoptosis through MTT assay and flow cytometry, and the cell migration by transwell migration assay.@*RESULTS@#The expression of TRAF1 was increased in BGC823, SGC7901, and MGC803 gastric cancer cell lines compared with gastric epithelial cells (P<0.05), and the highest expression was in BGC823 gastric cell line. In the three TRAF1 shRNAs, the strongest interference efficiency shRNA was pLVX-shRNA-TRAF1-shRNA2. When the gene TRAF1 of BGC823 was interfered, the cell growing power was weakened and the apoptosis rate increased, and the cell migration had no difference.@*CONCLUSION@#The expression of TRAF1 is up-regulated in gastric cancer cell lines BGC823, SGC7901, and MGC803, and the most obvious one is BGC823. The interference targeting TRAF1 can successfully inhibit the expression of TRAF1 in gastric cancer cell line BGC823. TRAF1 can inhibit the apoptosis of BGC823 cells.

Senescent endothelial dysfunctions were mediated by S1P2 receptor in cultured human umbilical vein endothelial cells / 中南大学学报(医学版)

OBJECTIVE@#To investigate the variation of senescent endothelial function by regulating the sphingosine-1-phosphate receptor type 2 (S1P2) expression in cultured human umbilical vein endothelial cells (HUVECs).@*METHODS@#The S1P2 receptor expression was regulated by transfecting the cDNA or shRNA of S1P2 in cultured HUVECs. The expression levels of S1P2 receptor in HUVECs were detected by RT-PCR and Western blot. EC chemotaxis was measured by the transwell migration assay. The wound healing assay was performed by a scratch wound model on EC monolayer. Matrigel morphogenesis assay was employed to assess the in vitro angiogenic responses.@*RESULTS@#After up-regulating the S1P2 expression in young ECs, the S1P-stimulated formation of a tubular-like network in Matrigel was dramatically diminished in transfected ECs (P<0.05). Quantification of the wound healing assay showed that transfected ECs grew much slower than young ECs (P<0.05). The chemotactic capability was significantly decreased in transfected ECs (P<0.05). Furthermore, the senescent-associated impairments were revoked by the downregulation of S1P2 receptor in senescent HUVECs.@*CONCLUSION@#The impaired functions (chemotactic, wound-healing and morphogenetic responses) in senescent HUVECs in vitro are mediated by S1P2 receptor.

Chronic Helicobacter pylori infection induces the proliferation and apoptosis in gastric epithelial cells and gastric precancerosis in Mongolian gerbils / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of different Helicobacter pylori (H.pylori) clinical strains on the proliferation and apoptosis of gastric epithelial cells, and to observe the effect of H.pylori on gastric mucosa by Mongolian gerbil model infected H.pylori.@*METHODS@#H.pylori isolates harvested from pathologically documented gastric carcinoma (GC, n=10) or chronic gastritis specimens (CG, n=10) were co-cultured with GES-1 cells individually. MTT assay and flow cytometry were used to determine the proliferation and apoptosis of GES-1 cells induced by H.pylori isolates. Mongolian gerbils were infected by the most (A strain) and the least (B strain) significantly proliferated H.pylori strains. Results When co-cultured with the cell/bacteria concentration ratio 1:1 and 1:50 for 12 h and the cell/bacteria concentration ratio 1:50 for 24 h, H.pylori clinical strains isolated from patients with gastric cancer promoted the proliferation of GES-1 cells, and there was significant difference in the absorbance compared with the group of gastritis strains(P0.05). The incidences of intestinal metaplasia and dysplasia in the A strain group were significantly higher than those in the B strain group (P<0.05).@*CONCLUSION@#H.pylori strains from different disease sources have different effects on the proliferation of GES-1 cells. H.pylori isolated from gastric cancer can promote the proliferation of cells to different degrees and directly induce gastric precancerosis and gastric cancer.

Detecting atrial fibrillation and normal sinus rhythm by R-R intervals / 生物医学工程学杂志

This paper aims to find a new method of detecting atrial fibrillation (AF) with fast responding speed and high detecting precision by R-R intervals. Probability density function (PDF) of distance between two points in the reconstructed phase space of R-R intervals of normal sinus rhythm (NSR) and AF is studied. It is found that the distribution of PDF between NSR and AF R-R intervals is significantly different; and based on this finding, a characteristic parameter k is defined. k is used for defection among 400 NSR and 400 AF R-R intervals. The results demonstrate that the new algorithm has fast responding speed and high detecting precision (average sensitivity 97.0%, average specificity 95.2%).

Application of Da Vinci surgical system in the treatment of hepatopancreatobiliary diseases / 中华消化外科杂志

Objective To evaluate the effect of Da Vinci surgical system for the treatment of hepatopancreatobiliary diseases.Methods The clinical data of 29 patients with hepatopancreatobiliary diseases who had undergone operations with Da Vinci surgical system from March to November 2009 at the General Hospital of PLA were retrospectively analyzed.Results The operations were successfully done on 28 patients,except 1 patient was converted to open pancreaticoenterostomy.The total operation time was(339±149)minutes,and the time for operations done with Da Vinci surgical system was(285±117)minutes.The postoperative bowl movement recovery time was(33±21)hours,and the length of postoperative hospital stay was(8±6)days.No blood transfusion was needed.Three patients had postoperative complications and were cured by conservative treatment.Conclusion Laparoscopic operations for hepatopancreatobiliary diseases can be applied with the help of the threedimensional imaging system and flexible surgical instruments of the Da Vinci surgical system,and its superiority is more obvious when applied for intractable hepatopancreatobiliary diseases.

Thirteen cases of major complication after percutaneous transhepatic biliary drainage / 中国医师进修杂志

Objective To investigate and cure major complications after percutaneous transhepastic biliary drainage(PTBD).Methods The clinical data of 13 major complications after PTBD were retrospectively analyzed,5 complications were acute and the other 8 complications were delayed.Two cases were dealed with intervention.and operations were performed for the other 11 patients immediately.Results Among the 7 patients who received one-stage operation,3 patients were accompanied with acute kidney failure,and 2 patients were died.Two patients who received the second-stage operation recovered snccessfully.Two patients who surrendered were surrived 3 and 8 months respectively.Conclusions It is difficult to deal with the major complications after PTBD,and the main cause of postoperative death is acute kidney failure.It will be helpful to deal with the primary disease on the second-stage.

An improved PID algorithm for temperature control used by tumor combined therapeutic instrument / 生物医学工程学杂志

The development of a multi-functional tumor combined therapeutic instrument based on improved PID algorithm is introduced. It is based on the theory of 1 + 1 = 3 or 1 + 1 + 1 > 3 curative effect enhancement by tumor combined therapy, and it can be used solely, or with the combination of chemotherapy or actinotheraphy or both for tumor hyperthermia. By adopting improved PID temperature control algorithm, the problem of temperature control precision reduction due to process characteristics changing with different heaters was solved, thus ensuring homogeneous and smooth radio frequency heating by different heaters to intracavity tumor foci. These experiments demonstrated that the new algorithm has strong adaptability and anti-disturbance capability, the equipment works stably and reliably, and it can control therapeutic temperature precisely (+/- 0.1 degree C), which indicates a good value in clinical application.