Effects of persistent Echinococcus multilocularis infections on hepatic fibrosis in mice / 中国血吸虫病防治杂志

Objective To investigate the effects of persistent Echinococcus multilocularis infections on hepatic fibrosis in mice, so as to provide insights into the understanding of liver fibrogenesis induced by E. multilocularis infections and the treatment of alveolar echinococcosis. Methods Hepatic stellate HSC-T6 and LX-2 cells were exposed to the sera (25, 50 and 100 μL) from Meriones unguiculatus infected with E. multilocularis, and E. multilocularis, germinal layer cells (GCs) and protoscoleces (PSCs) for 48 hours, respectively. The cell proliferation was measured using a CCK-8 assay, and the levels of collagen 1 (Col1) and α-smooth muscle actin (α-SMA) were measured in the culture supernatant of HSC-T6 cells using ELISA. In addition, the serum and liver samples were collected 1, 2, 4, 6, 8 months post-infection with E. multilocularis, respectively. The serum Col1 and α-SMA concentrations were measured using enzyme-linked immunosorbent assay (ELISA), and the deposition of collagen fibers was examined in mice livers using Sirius red staining. Results The sera of E. multilocularis-infected gerbils promoted the proliferation of HSC-T6 and LX-2 cells in vitro, and there were significant differences seen in the proliferative rate of HSC-T6 (FHSC-T6 = 126.50, P < 0.05) and LX-2 cells (FLX-2 = 201.50, P < 0.05) among different serum groups, with the highest proliferative rate of HSC-T6 (573.36% ± 206.34%) and LX-2 cells (940.38% ± 61.65%) found following exposure to 100 μL mouse sera. Exposure to serum from E. multilocularis-infected gerbils resulted in an increase in the Col1 and α-SMA levels in the culture supernatant of HSC-T6 cells, with the greatest Col1 (20.99 ng/mL ± 2.01 ng/mL) and α-SMA levels (305.52 pg/mL ± 16.67 pg/mL) measured following exposure to 100 μL sera. The metacestodes (142.65% ± 9.17% and 189.99% ± 7.75%), GCs (118.55% ± 8.96% and 122.54% ± 0.21%) and PSCs of E. multilocularis (156.34% ± 17.45% and 160.59% ± 31.41%) all promoted the proliferation of HSC-T6 and LX-2 cells in vitro, and there were significant differences in the proliferative rates of HSC-T6 (FHSC-T6 = 11.24, P < 0.05) and LX-2 cells among groups (FLX-2 = 47.72, P < 0.05). Exposure to E. multilocularis resulted in an increase in Col1 and α-SMA levels in the culture supernatant of HSC-T6 cells, and the highest Col1 (4.43 ng/mL ± 2.23 ng/mL) and α-SMA levels (285.20 pg/mL ± 90.67 pg/mL) were detected following treatment with E. multilocularis metacestodes. In addition, a persistent increase was seen in the deposition of collagen fibers in mice livers 1 to 8 months post-infection with E. multilocularis, with the greatest Col1 level (280.26 ng/mL ± 23.04 ng/mL) seen 6 months post-infection and the highest α-SMA level (33.68 ng/mL ± 4.45 ng/mL) detected 8 months post-infection, respectively. Conclusions Persistent E. multilocularis infections promote hepatic stellate cell proliferation, induce an increase in mouse serum Col1 and α-SMA levels, and cause elevated deposition of collagen fibers in mice livers. The infective stage of E. multilocularis is a critical period for inducing hepatic fibrosis of alveolar echinococcosis.

Changes of left ventricular remodeling in hypertension patients with carotid atherosclerosis of phlegm-dampness syndrome / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study changes of left ventricular remodeling (LVR) in hypertension patients with carotid atherosclerosis (CAS) of phlegm-dampness syndrome (PDS).</p><p><b>METHODS</b>Doppler ultrasonography data of CAS were observed in 223 hypertension patients with CAS (as the hypertension group, including 119 patients of the PDS group and 104 of the non-PDS group), 81 CAS patients with non-hypertension, and 19 non-hypertension non-CAS patients (as the control group). The difference in the degree of LVR was compared among the above groups.</p><p><b>RESULTS</b>The left ventricular posterior wall thickness (LVPWT), inter ventricular septum thickness (IVS), E/A were higher in the hypertension group than in the non-hypertension group (P < 0.05). The left ventricular end-diastolic dimension (LVEDD), left ventricular end-systolic diameter (LVESD), stroke volume (SV) were higher in the soft plaque hypertension group and the soft plaque non-hypertension group than in the hard plaque group, the thickening intimal group, and the normal intimal group (P < 0.01 , P < 0.05). The LVEDD, LVESD, and SV were higher, and the ejection fraction (EF) was lower in the PDS hypertension group than in the non-PDS hypertension group (all P < 0.05). Of them, LVEDD, LVESD, and SV were higher in the soft plaque group than in the hard plaque group (P < 0.01), the thickening intimal group (P < 0.01) and the normal intimal group (P < 0.05). There was no statistical difference in PDS hypertension between the soft plaque group and the hard plaque group (P > 0.05).</p><p><b>CONCLUSION</b>The hypertension patients with CAS of PDS might be correlated to LVR, and LVR was more obviously in the soft plaque patients.</p>

Relationship between carotid atherosclerosis and cerebral infarction / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To study the relationship between carotid atherosclerosis and cerebral infarction (CI).</p><p><b>METHODS</b>Between November 2008 and March 2009, 147 CI patients (CI group) and 48 patients with non-cerebrovascular diseases (control group) were enrolled from inpatients of Neurology Department of our hospital. The diagnostic criterion of thickened carotid intima was set as 1.0 mm<intima-media thickness (IMT) < 1.5 mm and that of carotid plaque was as IMT 1.5 mm. Carotid atherosclerosis was divided into three levels: normal intima, thickened intima, and plaque formation. The color Doppler ultrasonography data of carotid arteries in all patients were analyzed and the severity of carotid atherosclerosis was compared between the two groups.</p><p><b>RESULTS</b>In the CI group, 36 (24.5%) patients had normal carotid intima, 22 (15.0%) had thickened carotid intima, and 89 (60.5%) had carotid plaque. In the control group, 22 (45.8%) patients had normal carotid intima, 4 (8.3%) had thickened carotid intima, and 22 (45.8%) had carotid plaque. The severity of carotid atherosclerosis in the CI group was higher than that in the control group (P = 0.022). There was significant difference in the constitution of carotid plaque between the two groups (P = 0.001); the CI group mainly had the soft plaque (55/89, 61.8%), whereas the control group mainly had the hard plaque (17/22, 77.3%). The first three common locations of carotid plaque in both groups were carotid bifurcation (CI group: 73.7%; control group: 64.1%), common carotid artery (CI group: 20.4%; control group: 25.6%), and internal carotid artery (CI group: 5.9%; control group: 10.3%). The location of carotid plaque between the two groups was not significantly different (P = 0.438). There was no difference in the carotid inner diameter or resistance index between the two groups (P > 0.05).</p><p><b>CONCLUSIONS</b>Carotid atherosclerosis is to some extent able to reveal the atherosclerotic condition of cerebral arteries and act as an important predictor for the risk of CI. The color Doppler ultrasonography of carotid arteries can provide a convenient way for the prevention and treatment of CI.</p>

Time course of myocardial NF-kappaB activation post coronary microembolization / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the time course of myocardial NF-kappaB activation and association with cardiac function and other pro-inflammation cytokines following coronary microembolization (CME).</p><p><b>METHODS</b>CME was induced by homologous microthrombotic particle suspension injection into left ventricle with simultaneous short-term ascending aorta clamping. The CME rats were randomized to untreated group and pyrrolidine dithiocarbamate (PDTC, a specific NF-kappaB inhibitor) treated group (n = 32 respectively). The rats were sacrificed on day 1, 3, 7 and 14 post-operationally (n = 8 each). Twenty-four rats were sham-operated and served as controls. NF-kappaB DNA-binding activity was evaluated by electrophoretic mobility shift assay (EMSA), protein expressions of TNFalpha, IL-6 and ICAM-1 were analyzed by Western blotting, the dynamic alterations of TNFalpha, IL-6 and ICAM-1 mRNA were quantitatively assessed by Real-time PCR post hemodynamic measurements.</p><p><b>RESULTS</b>NF-kappaB DNA-binding activity in CME group was significantly increased than that of sham group on day 1, peaked at day 3 and was similar as that in sham rats on day 14. The protein and mRNA expressions of TNFalpha, IL-6 and ICAM-1 were significantly increased in CME group at various time points compared those in sham rats. NF-kappaB DNA-binding activity positively correlated with mRNA expressions of TNFalpha, IL-6, ICAM-1, respectively (r = 0.72, P < 0.05; r = 0.94, P < 0.01; r = 0.62, P < 0.05). PDTC significantly suppressed protein and mRNA expressions of TNFalpha, IL-6 and ICAM-1 (P < 0.05) and improved left ventricular function.</p><p><b>CONCLUSION</b>NF-kappaB activation post CME could upregulate the gene transcriptions of TNFalpha, IL-6, ICAM-1 and enhance inflammatory responses and aggravate left ventricular dysfunction.</p>

Application of bioinformatics in researches of industrial biocatalysis / 生物工程学报

Industrial biocatalysis is currently attracting much attention to rebuild or substitute traditional producing process of chemicals and drugs. One of key focuses in industrial biocatalysis is biocatalyst, which is usually one kind of microbial enzyme. In the recent, new technologies of bioinformatics have played and will continue to play more and more significant roles in researches of industrial biocatalysis in response to the waves of genomic revolution. One of the key applications of bioinformatics in biocatalysis is the discovery and identification of the new biocatalyst through advanced DNA and protein sequence search, comparison and analyses in Internet database using different algorithm and software. The unknown genes of microbial enzymes can also be simply harvested by primer design on the basis of bioinformatics analyses. The other key applications of bioinformatics in biocatalysis are the modification and improvement of existing industrial biocatalyst. In this aspect, bioinformatics is of great importance in both rational design and directed evolution of microbial enzymes. Based on the successful prediction of tertiary structures of enzymes using the tool of bioinformatics, the undermentioned experiments, i.e. site-directed mutagenesis, fusion protein construction, DNA family shuffling and saturation mutagenesis, etc, are usually of very high efficiency. On all accounts, bioinformatics will be an essential tool for either biologist or biological engineer in the future researches of industrial biocatalysis, due to its significant function in guiding and quickening the step of discovery and/or improvement of novel biocatalysts.

Study on production of acrylamide by microbial method (II)--enzyme catalytic kinetics and de-active dynamics of nitrile hydratase / 生物工程学报

The hydration reaction by microbial method is the crisis of the procedure of acrylamide production from acrylonitrile. This research studied the enzyme catalytic kinetics and de-active kinetics of nitrile hydratase in the type of free cell. Firstly, the effects of the concentration of cells, the temperature, pH value, the concentration of acrylonitrile and the concentration of acrylamide on the activity of nitrile hydratase was investigated. The result is that the temperature and the concentration of acrylamide are the most important among these factors. The activity of the nitrile hydratase was 5659 u/mL (broth) at 28 degrees C; the counterpart was only 663 u/mL (broth) at 5 degrees C. And the activity of NHase in solution of 45% acrylamide was just about half of that in solution of 5% acrylamide. After study on the relation of temperature and the reaction speed, It was found that the activation energy of the hydration of NHase was 65.57 kJ.mol-1. This paper studied the effects of concentration of cells, temperature, pH value, concentrations of acrylonitrile and acrylamide on the deactivation of Nhase, as well as the related enzyme de-active kinetics. The result also showed that the temperature and the concentration of acrylamide are the most important among these factors. In solution of 35% acrylamide, the residual activity was about 0% of the original value after 55 h; but in solution of 10% acrylamide, after the same period of time, the residual activity was 50% of the original one. It was also found that the concentration of acrylonitrile had little effect on the stability of NHase. The coefficient of deactivation at 28 degrees C was 21.77 times of the one at 5 degrees C. Correlating the temperature and the coefficient of deactivation, the activation energy of the de-active reaction was found to be 92.28 kJ.mol-1.

Study on production of acrylamide by microbial method (I)--Culture of bacterium cells and expression of high activity of nitrile hydratase / 生物工程学报

The cultural conditions for the growth of Norcardia cell were studied in this paper. Controlling pH value, adding nutrient and optimizing the quantity of inducer during cultivation, the activity of nitrile hydratase reached 6567 u/mL (culture medium), which was the highest value appeared in native journals. In the farther hydratase experiments, no by-product, crylic acid, was detected. It showed that the activity of amidase was not promoted obviously while the activity of nitrile hydratase was increased greatly. The results set a strong foundation for the industrial application and the research on new technology.