Anti-inflammatory Mechanism of Modified Erchentang on Chronic Obstructive Pulmonary Disease Through Jagged1/Notch1/Hes1 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of modified Erchentang on the expression of key molecules in the Jagged1/Notch1/Hes1 signaling pathway in lung tissues of rats with chronic obstructive pulmonary disease （COPD） and explore its anti-inflammatory effect and molecular mechanism on COPD through the Jagged1/Notch1/Hes1 signaling pathway. MethodSixty SD rats were randomly divided into normal group， model group， low-， medium-， and high-dose modified Erchentang groups （5， 10， 20 g·kg-1）， and γ-secretase inhibitor DAPT group （0.02 g·kg-1）， with 10 rats in each group. The COPD model was induced in rats by cigarette smoking combined with intratracheal instillation of lipopolysaccharide （LPS）. Rats were treated with corresponding drugs by gavage， while those in the normal group and the model group were treated with the same amount of normal saline by gavage. The serum levels of Notch1， soluble intercellular adhesion molecule-1 （sICAM-1）， activated leukocyte cell adhesion molecule （ALCAM）， and soluble vascular adhesion molecule-1 （sVCAM-1） were detected by enzyme-linked immunosorbent assay （ELISA）. The mRNA expression of Jagged1， Notch1， and Hes1 was detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The protein expression of Jagged1， Notch1， Notch1 intracellular domain （NICD1）， and Hes1 in lung tissues of rats was detected by immunohistochemistry （IHC）. ResultCompared with the normal group， the model group showed increased serum content of Notch1， sICAM-1， ALCAM， and sVCAM-1 （P<0.01）， increased mRNA expression of Jagged1， Notch1， and Hes1 in lung tissues （P<0.01）， and increased protein expression of Jagged1， Notch1， NICD1， and Hes1 （P<0.01）. Compared with the model group， the medium- and high-dose modified Erchentang groups and the DAPT group showed decreased serum content of Notch1， sICAM-1， ALCAM， and sVCAM-1 （P<0.05， P<0.05）， down-regulated mRNA expression of Jagged1， Notch1， and Hes1 （P<0.05， P<0.01）， and reduced protein expression of Jagged1， Notch1， NICD1， and Hes1（P<0.05， P<0.01）. ConclusionModified Erchentang may inhibit the inflammatory response in the lung of COPD rats， and its mechanism may be related to the resistance of inflammatory injury in the lung by decreasing the mRNA expression of Jagged1， Notch1， and Hes1 and inhibiting the release of Notch1， sICAM-1， ALCAM， and sVCAM-1.

Effect of Modified Erchentang on Bronchioles of Rats with Chronic Obstructive Pulmonary Disease by HMGB1/RAGE/NF-κB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo study the effect of modified Erchentang on the expression of key molecules in the high mobility group Box 1 protein （HMGB1）/receptor for advanced glycation endproduct （RAGE）/nuclear factor-κB （NF-κB） signaling pathway in bronchioles of rats with chronic obstructive pulmonary disease （COPD）， to explore the mechanism of modified Erchentang against bronchiolar inflammation of COPD rats via HMGB1/RAGE/NF-κB signaling pathway. MethodSixty SD rats were randomly divided into normal group， model group， modified Erchentang low-， medium- and high-dose groups （5， 10， 20 g·kg-1·d-1） and ethyl pyruvate （HMGB1 inhibitor） group， with 10 in each group. The COPD rat model was prepared by cigarette smoke combined with tracheal injection of lipopolysaccharide （LPS）. After modeling， the modified Erchentang groups were given corresponding drugs （ig） and Ringer's solution （4 mL， ip）， while the EP group was treated with equal volume of normal saline （ig） and EP （0.04 g·kg-1·d-1， ip）. The normal group and the model group received equal volume of normal saline （ig） and Ringer's solution （ip） for 21 consecutive days. The contents of HMGB1， chemokine （C-X-C motif） ligand 1 （CXCL1）， CXCL2 and monocyte chemotactic protein-1 （MCP-1） in bronchoalveolar lavage fluid （BALF） were detected by enzyme-linked immunosorbent assay （ELISA）. The mRNA expressions of HMGB1， RAGE and NF-κB p65 were determined by Real-time polymerase chain reaction （Real-time PCR）， and the protein expressions of HMGB1， RAGE， p-NF-κB p65， and alpha-smooth muscle actin （α-SMA） in bronchioles tissue of rats were determined by immunohistochemistry （IHC）. ResultCompared with the conditions in the normal group， the forced vital capacity （FVC）， forced expiratory volume in the first second （FEV1） and FEV1/FVC in the model group were decreased （P<0.01） while the contents of HMGB1， CXCL1， CXCL2 and MCP-1 in BALF were increased （P<0.01）. And the model group presented higher mRNA expressions of HMGB1， RAGE and NF-κB p65 （P<0.01） and protein expressions of HMGB1， RAGE， p-NF-κB p65 and α-SMA （P<0.05， P<0.01） than the normal group. Compared with the model group， the modified Erchentang medium- and high-dose groups had increased FEV1/FVC （P<0.05， P<0.01）， lowered contents of HMGB1， CXCL1， CXCL2 and MCP-1 in BALF （P<0.05， P<0.05）， and reduced mRNA expressions of HMGB1， RAGE and NF-κB p65 （P<0.05， P<0.01） and protein expressions of HMGB1， RAGE， p-NF-κB p65 and α-SMA （P<0.05， P<0.01）. ConclusionModified Erchentang can resist bronchiolar inflammation of COPD rats. The mechanism may be related to down-regulating the mRNA expressiona of HMGB1 and RAGE， inhibiting the activity of NF-κB， and reducing the release of HMGB1， CXCL1， CXCL2 and MCP-1， thus suppressing the inflammatory injury and abnormal repair of bronchioles.

Effect and Mechanism of Cxcr4 Gene-Modified BMSC-Derived Exosomes on Aplastic Anemia / 中国实验血液学杂志

OBJECTIVE@#To explore the improvement effect of CXC chemokine receptor 4 (Cxcr4) gene-modified bone marrow mesenchymal stem cell (BMSC)-derived exosomes on aplastic anemia (AA), and make a preliminary exploration of the mechanism.@*METHODS@#Mouse BMSCs were isolated and cultured, then infected by recombinant lentivirus carrying Cxcr4 gene. The expression of green fluorescence was observed through fluorescence microscope, the expression of Cxcr4 mRNA was detected by real-time fluorescence quantitative PCR, and the BMSC-derived exosomes modified with Cxcr4 gene were extracted. Mouse models of AA were constructed, and control group, model group (AA), AA+BMSC group, AA+NC-BMSC group, AA+Cxcr4-BMSC group were set up. Except control group and model group, the other three groups of mice were injected 400 μl exosomes from different sources via the tail vein, after 2 weeks, the routine blood indices and the number of bone marrow nucleated cells were detected, the pathological changes of bone marrow were observed by HE staining, and the expression level of Treg cells was detected by flow cytometry.@*RESULTS@#Mouse BMSCs were successfully isolated, and BMSCs with high expression of Cxcr4 and their exosomes were obtained. Compared with the control group, the number of red blood cell (RBC), white blood cell (WBC), and platelet (PLT), the hemoglobin (Hb) content and proportion of Treg cells in the peripheral blood of mice in the model group significantly decreased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01). The proliferation level of nucleated cells was low, and the medullary cavity was filled with a large number of fat cells. Compared with the model group, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+BMSC group, AA+NC-BMSC group, and AA+Cxcr4-BMSC group significantly increased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01), and pathological changes of bone marrow were improved. In addition, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+Cxcr4-BMSC group were significantly higher than those in the AA+BMSC group (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01).@*CONCLUSION@#Injection of Cxcr4 gene-modified BMSC-derived exosomes has a certain improvement effect on AA mice, and the mechanism may be related to an increase of the proportion of Treg cells.

Clinical Observation of Suanzaoren Tang Combined with Fluoxetine in Treatment of Depression of Liver Stagnation and Blood Deficiency Accompanied by Insomnia / 中国实验方剂学杂志

Objective:To observe the clinical therapeutic effect of Suanzaoren Tang combined with fluoxetine in the treatment of patients with depression of liver stagnation and blood deficiency accompanied by insomnia. Method:The patients with depression of liver stagnation and blood deficiency accompanied by insomnia （120 cases） were randomly divided into an observation group and a control group， with 60 cases in each group. The patients in the observation group received Suanzaoren Tang combined with fluoxetine， and those in the control group received fluoxetine. The course of treatment was eight weeks. The clinical efficacy was evaluated with Hamilton Depression Rating Scale （HAMD）， Pittsburgh Sleep Quality Index（PSQI）， and Activities of Daily Living （ADL） score. Enzyme-linked immunosorbent assay （ELISA） was used to determine the plasma levels of 5-hydroxytryptamine （5-HT）， norepinephrine （NE），brain-derived neurotrophic factor （BDNF）， glial cell-derived neurotrophic factor （GDNF）， neuron-specific enolase （NSE）， and S100<italic>β</italic>. Result:After eight weeks of treatment， the scores of HAMD and PSQI were reduced（<italic>P</italic><0.01）， while the scores of ADL were elevated（<italic>P</italic><0.01），and the levels of 5-HT， NE， GDNF and BDNF were up-regulated （<italic>P</italic><0.01） in the plasma of patients in the observation group as compared with those before treatment. After treatment， compared with the control group， the observation group showed increased total effective rate（<italic>P</italic><0.01）， decreased scores of HAMD and PSQI （<italic>P</italic><0.01）， elevated score of ADL（<italic>P</italic><0.01）， up-regulated levels of 5-HT， NE， GDNF and BDNF in plasma， and declining NSE and S100<italic>β</italic>（<italic>P</italic><0.01）. Conclusion:Suanzaoren Tang combined with fluoxetine is superior to fluoxetine alone in treating the depression of liver stagnation and blood deficiency accompanied by insomnia. Its therapeutic effect is achieved by increasing the release of monoamine neurotransmitters and promoting the secretion of BDNF and GDNF in the brain.

Mechanism of Modified Erchentang on Expression of CXCL8-CXCR1/2 Axle Genes in Lung Tissue of Rats with Chronic Obstructive Pulmonary Disease / 中国实验方剂学杂志

Objective:To observe the effect of modified Erchentang on the expression of CXC chemokine ligand (CXCL) 8-CXC chemotaxis factor receptor (CXCR) 1/2 genes in the lung tissue of rats with chronic obstructive pulmonary disease (COPD), in order to explore the anti-inflammatory molecular mechanism of Erchentang on COPD. Method:Forty SD rats were randomly divided into normal group, model group, Jizhi syrup group and modified Erchentang group. COPD models in rats were prepared by cigarette smoke and dripping lipopolysaccharide (LPS) in the trachea. After modeling, normal and model groups were intragastrically given normal saline solution, Jizhi syrup group was given Jizhi syrup（10 g·kg-1），and modified Erchentang group was given intragastrically corresponding herbal drugs (10 g·kg-1) for 14 days. The levels of chemokines CXCL1, CXCL8 were detected by enzyme-linked immunosorbent assay in rat bronchoalveolar lavage fluid (BALF). The mRNA expressions of CXCL8, CXCR1 and CXCR2 were detected by quantitative real time PCR (Real-time PCR). Western blot was used to detect the levels of CXCL8, CXCR1 and CXCR2 protein, the pathological changes of lung tissues were observed by hematoxylin-eosin(HE) staining,and immunohistochemistry (IHC) method was used to detect the expressions of CXCL8, CXCR1 and CXCR2 protein in the lung tissue of all the groups. Result:The levels of chemokines CXCL1, CXCL8 in rats BALF were increased significantly (P<0.01), the expressions of CXCL8，CXCR1 and CXCR2 mRNA and protein were increased significantly (P<0.05, P<0.01) in model group compared with normal group. Compared with model group, the expressions of CXCL8, CXCR1 and CXCR2 mRNA and protein were decreased significantly (P<0.05), and the levels of chemokines CXCL1, CXCL8 in rats BALF were decreased significantly (P<0.01) in modified Erchentang. Conclusion:Modified Erchentang has an anti-inflammatory effect on COPD. The mechanism may be related to inhibiting the expressions of CXCL8, CXCR1, CXCR2 mRNA and protein, and reducing the release of chemokines CXCL1, CXCL8.

Regulatory Effect of Modified Erchentang on Levels of Lymphokines Relating to Th1,Th2 and Th9 Cells and Expressions of IL-4R1/IL-13RA1 in Bronchioles of Rats with Chronic Obstructive Pulmonary Disease / 中国实验方剂学杂志

Objective:To study the effect of modified Erchentang on levels of interleukin-12 (IL-12), interferon-γ (IFN-γ), interleukin-9 (IL-9), interleukin-4 (IL-4) and interleukin-13 (IL-13) in plasma and bronchoalveolar lavage fluid (BALF) of all rats, as well as expressions of interleukin-4 (IL-4) receptor (IL-4R1) and interleukin-13 (IL-13) receptor (IL-13RA1) in bronchioles tissue of rats with chronic obstructive pulmonary disease (COPD). Method:Fifty SD rats were randomly divided into 5 groups, namely normal group, model group, and low, middle and high-dose modified Erchentang groups (5, 10, 20 g·kg-1), with 10 rats in each group. COPD in rat was prepared by using cigarette smoke combined with dripping lipopolysaccharide (LPS) in trachea. After the modeling, normal and model groups were given normal saline solution through intragastric (ig) administration, while other groups were given corresponding herbal drugs (5, 10, 20 g·kg-1) intragastrically (ig) for 14 days. The levels of IL-12, IFN-γ, IL-9, IL-4 and IL-13 in plasma and BALF were detected by Enzyme-linked immunosorbent assay (ELISA) method， and immunohistochemistry (IHC) method was used to detect the expressions of IL-4R1 and IL-13RA1 in bronchioles tissue of all of the groups. Result:Compared with the normal group, the levels of IL-12 and IFN-γ were decreased significantly (P<0.01), but the levels of IL-9, IL-4 and IL-13 in plasma and BALF were significantly increased (P<0.01), and the expressions of IL-4R1 and IL-13RA1 in bronchioles tissue were increased significantly (P<0.01) in model group. Compared with the model group, the levels of IL-12 and IFN-γ were increased significantly, while the levels of IL-9, IL-4 and IL-13 in plasma and BALF were decreased significantly (P<0.01), and the expressions of IL-4R1 and IL-13RA1 in bronchioles tissue were decreased significantly (P<0.01) in modified Erchentang groups (10, 20 g·kg-1). Conclusion:Modified Erchentang has effects in resisting inflammatory and protecting tissue structure of bronchioles. Its mechanism may be correlated with increasing the levels of IL-12, IFN-γ and reducing the levels of IL-9, IL-4 and IL-13 in plasma and BALF, and inhibiting the expressions of IL-4R1 and IL-13RA1 in bronchioles tissue.

Astrocytic GABA Receptors in Mouse Hippocampus Control Responses to Behavioral Challenges through Astrocytic BDNF / 神经科学通报·英文版

Major depressive disorder (MDD) is a common mood disorder that affects almost 20% of the global population. In addition, much evidence has implicated altered function of the gamma-aminobutyric acid (GABAergic) system in the pathophysiology of depression. Recent research has indicated that GABA receptors (GABARs) are an emerging therapeutic target in the treatment of stress-related disorders such as MDD. However, which cell types with GABARs are involved in this process is unknown. As hippocampal dysfunction is implicated in MDD, we knocked down GABARs in the hippocampus and found that knocking down these receptors in astrocytes, but not in GABAergic or pyramidal neurons, caused a decrease in immobility in the forced swimming test (FST) without affecting other anxiety- and depression-related behaviors. We also generated astrocyte-specific GABAR-knockout mice and found decreased immobility in the FST in these mice. Furthermore, the conditional knockout of GABARs in astrocytes selectively increased the levels of brain-derived neurotrophic factor protein in hippocampal astrocytes, which controlled the decrease in immobility in the FST. Taken together, our findings contribute to the current understanding of which cell types expressing GABARs modulate antidepressant activity in the FST, and they may provide new insights into the pathological mechanisms and potential targets for the treatment of depression.

Mechanism of Modified Erchentang on Signaling Pathway of TLR4/MyD88/NF-κB in Lung Tissue of Rats with Chronic Obstructive Pulmonary Disease / 中国实验方剂学杂志

Objective: To study the effect of modified Erchentang on expressions of Toll-like receptor 4 (TLR4), myeloid differentiation factor (MyD88) and nuclear factor-κB (NF-κB) genes in the lung tissue homogenate of rats with chronic obstructive pulmonary disease (COPD). Method: Forty SD rats were randomly divided into normal group, model group, modified Erchentang group and EVP4593 (NF-κB inhibitor) group. Rat COPD models were prepared through cigarette smoke and tracheal dripping with lipopolysaccharide (LPS). After the modeling, normal and model groups were intragastrically given normal saline solution, EVP4593 group was given EVP4593(1 mg · kg-1) through subcutaneous injection, and modified Erchentang group was given corresponding herbal drugs intragastrically (10 g · kg-1) for 14 days. The levels of high mobility group box 1(HMGB1), chemokines CXCL-2, CXCL-3 and monocyte chemoattractant protein-1 (MCP-1) in rats serum were detected by enzyme-linked immunosorbent assay in rats serum. The expressions of Toll-like receptors 4(TLR4), myeloid differentiation factor (MyD88) and nuclear factor-κB p65 (NF-κB p65) mRNA were detected by Real-time fluorescence quantitative PCR (Real-time PCR) method. Western blot were used to detect the levels of TLR4, MyD88, NF-κB p65 and p-NF-κB p65 protein. Immunohistochemistry (IHC) method was used to detect the localization and expressions of TLR4, MyD88 and p-NF-κB p65 protein in the lung tissue. Result: The mRNA and protein expressions of TLR4, MyD88 and NF-κB p65 were increased significantly (PPκB p65 mRNA and protein were decreased significantly (PConclusion: Modified Erchentang may inhibit the inflammatory response of COPD effectively. The mechanism may be related to the inhibition of the expressions of the signal molecule genes involved in the TLR4/MyD88/NF-κB pathway and the reduction of the release of HMGB1, CXCL-2, CXCL-3 and MCP-1.

Effect of Modified Erchentang on NLRP3 Inflammasome Expression in Peripheral Blood Mononuclear Cells (PBMCs) of Rats with Chronic Obstructive Pulmonary Disease / 中国实验方剂学杂志

Objective: To observe the effect of modified Erchentang on the expressions of NLRP3 inflammasome genes in peripheral blood mononuclear cells (PBMCs) and the levels of interleukin-1β(IL-1β)and interleukin-18(IL-18)and chemokine8 (CXCL8) in lung tissue of rats with chronic obstructive pulmonary disease (COPD), in order to explore the molecular mechanism of modified Erchentang against inflammation of COPD. Method: Forty SD rats were randomly divided into normal control group, model group, MCC950 (NLRP3 inhibitor) group and modified Erchentang group. The COPD model of rats was prepared by using cigarette smoke and dripping with lipopolysaccharide (LPS). During the modeling period (from the 1st to the 30th day), the MCC950 group received a single intraperitoneal injection with 60 mg · kg-1 on the first day of the experiment,and the modified Erchentang group was given intragastric administration with 10 g · kg-1, once every 2 days. From the 31st to the 45th day, the MCC950 group was intraperitoneally injected with 3 mg · kg-1, once every 2 days, the modified Erchentang group was given intragastric administration with 10 g · kg-1, twice a day, and the normal group and the model group received normal saline (NS) with 10 g · kg-1, twice a day. The levels of interleukin-1β(IL-1β), interleukin-18(IL-18) and chemokine8 (CXCL8) in rats lung tissue homogenate were detected by enzyme-linked immunosorbent assay (ELISA). The expressions of NLRP3, apoptosis-associated speck-like protein (ASC) and cysteinyl aspartate specific proteinase-1 (Caspase-1) mRNA in PBMCs were measured by Real-time fluorescence quantitative PCR (Real-time PCR). Western blot was used to detect the levels of NLRP3, ASC and Caspase-1 proteins in PBMCs. Immunohistochemical(IHC)method was used to detect the expressions of NLRP3, ASC and Caspase-1 proteins in lung tissues. Result: The expressions of NLRP3, ASC and Caspase-1 mRNA and protein were increased significantly (PPPβ and CXCL8 in lung tissue homogenate in model group were significantly higher than those in the control group. However, compared with model group, the levels of IL-18, IL-1β and CXCL8 were decreased significantly (PPConclusion: NLRP3 inflammasome is involved in the inflammatory response in COPD rats. Modified Erchentang may inhibit the inflammatory response of COPD effectively. The mechanism may be correlated with the reduction of NLRP3, ASC and Caspase-1 gene expressions, and the inhibition of the release of IL-18, IL-1β and CXCL8.

Effect of Modified Erchentang on Expressions of Chemokine Receptor CXCR1/2 and CXCL8 in Patients with AECOPD / 中国实验方剂学杂志

Objective:To observe the clinical efficacy of modified Erchentang on CXC chemokine ligand receptors (CXCR1/2)and their ligands CXCL8,macrophage inflammatory protein -2(MIP-2) in patients of chronic obstructive pulmonary disease(AECOPD)at acute exacerbation stage,and assess the effect and mechanism of modified Erchentang on anti-inflammatory in patients of AECOPD. Method:This study was a multicenter, randomized single blind, controlled trial. The authors selected 200 cases in conformity to the standards of AECOPD. The AECOPD patients were randomly divided into modified Erchentang group and control group. In addition to the western medicine, modified Erchentang was also given to the modified Erchentang group, and Jizhitangjiang was given to the control group for 14 days. Each group was observed for the alleviation of the symptoms. Euzyme-linked immunosorbent assay (ELISA) was used to determine the levels of CXCL8 and MIP-2 in the patients' plasma of all groups before and after treatment. Western blot were used to detect the levels of CXCR1, CXCR2 and CXCL8 protein in peripheral blood mononuclear cells(PBMCs). Immunocytochemistry (ICC) method was used to detect the expressions of CXCL8, CXCR1 and CXCR2 protein in PBMCs. Result:The level of CXCL8 in plasma, and the expressions of CXCR1, CXCR2 and CXCL8 mRNA and protein in the modified Erchentang group were decreased significantly than those in the control group(PPConclusion:Modified Erchentang has an anti-inflammatory effect on AECOPD. Its mechanism may be related to the down-regulation of the expressions of CXCL8, CXCR1 and CXCR2, the reduction of synthesis and release of CXCL8 and MIP-2, the inhibition of the chemotaxis and activity of inflammatory cells, and the prevention of inflammation progress.

A comparative analysis of health promotion demand in practitioners between urban and rural private enterprises / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To assess the differences in the health promotion demand of practitioners between urban and rural private enterprises by a comparative analysis, and to probe into the more scientific and targeted health promotion measures.</p><p><b>METHODS</b>Stratified cluster random sampling and self-designed questionnaire were adopted to survey 852 practitioners in urban and rural private enterprises of a Chinese city.</p><p><b>RESULTS</b>There were significant differences in practitioners between the two sorts of enterprises in terms of age, length of service, educational level, and forms of employment (P < 0.05 or P < 0.01). The basic knowledge and skills of practitioners in rural private enterprises were worse than those in urban private enterprises(P < 0.05 or P < 0.01). Practitioners in rural private enterprises were significantly less inclined to gain basic health promotion knowledge through enterprise training and network(P < 0.01). The demand of practitioners for health examination and hazard notification was significantly lower in rural private enterprises than in urban private enterprises (P < 0.05).</p><p><b>CONCLUSION</b>Focused and targeted health promotion should be carried out based on different demand characteristics of practitioners in rural and urban private enterprises.</p>

Strychnos alkaloids inhibit the proliferation of adult rat neuroprogenitor cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of strychnos alkaloids on the proliferation of adult rat neuroprogenitor cells.</p><p><b>METHODS</b>Strychnos alkaloids free of strychnine and brucine were extracted from Strychnos nux vomica, and the effects of Strychnos alkaloids on the survival of HEK293 and PC12 cells were evaluated using MTT assay. In vitro cultured adult rat neuroprogenitor cells isolated from the hippocampus were treated with different concentrations of Strychnos alkaloids for 2 days, and the cell proliferation was assessed using BrdU incorporation assay.</p><p><b>RESULTS</b>At the concentration above 0.5 mg/ml, Strychnos alkaloids produced toxic effect against HEK293 cells (P<0.0001), while for PC12 cells, Strychnos alkaloids inhibited the cell survival at the concentration as low as 5 microg/ml (P<0.0001). After 2 days of exposure to 50 microg/ml Strychnos alkaloids, the neuroprogenitor cells showed significantly decreased number of BrdU-positive cells (P<0.01), but the total cell number remained stable when compared with that of the control cells (P>0.05), whereas at the concentration of 100 microg/ml, Strychnos alkaloids produced obvious cytotoxicity against the neuroprogenitor cells.</p><p><b>CONCLUSION</b>Strychnos alkaloids can significantly inhibit the proliferation of adult rat neuroprogenitor cells, and this effect is probably selective, suggesting the potential of Strychnos alkaloids as a new drug for treatment of neurocytoma.</p>

Developmental changes in synaptic and extrasynaptic N-methyl-D-aspartate receptors in cultured rat hippocampal neurons / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate changes in synaptic and extrasynaptic N-methyl-D-aspartate receptors (NMDAR) during the development of cultured rat hippocampal neurons.</p><p><b>METHODS</b>Synaptic and extrasynaptic NMDAR channel currents were recorded from 1-day-old rat hippocampal neurons cultured for 1 and 2 weeks with patch-clamp technique in whole-cell configuration and outside-out configuration, respectively.</p><p><b>RESULTS</b>The amplitude of NMDAR-mediated miniature excited postsynaptic current (Meps(CNMDA)) decreased in neurons cultured for 2 weeks as compared with that recorded in neurons cultured for 1 week, and the 2-week neurons showed also much lowered sensitivity to selective NR2B blocker ifenprodil. The amplitude and open probability of extrasynaptic NMDAR in the 2-week neurons were significantly higher than those in the 1-week neurons, but the neurons differred little in conduction and reverse potential. Ifenprodil decreased the high conductance and open probability in both neurons, but the effect was more potent in the 2-week ones.</p><p><b>CONCLUSIONS</b>There can be developmental changes in synaptic and extrasynaptic NMDAR channel currents in cultured rat hippocampal neurons, indicating that different NMDAR subtypes are expressed in the synaptic and extrasynaptic regions during the development of the hippocampal neurons. In 1-week neurons, NR2B are predominant both in synaptic and extrasynaptic regions, and at 2 weeks, synaptic NR2B are replaced by NR2A but NR2B still remains the predominant subtypes outside the synapses.</p>

Variability analysis of S2 gene of SARS-CoV / 南方医科大学学报

<p><b>OBJECTIVE</b>To determine the sequence of S2 gene of SARS-associated coronavirus (SARS-CoV) GD322 and analyze the phyletic evolution of S2 gene.</p><p><b>METHOD</b>S2 gene fragment was amplified from SARS-CoV GD322 genome with RT-PCR and ligated to pGEM-T vector for sequence analysis after transformation of the plasmid into E. coli DH5a. The variability of S2 genes and S2 proteins from 12 strains isolated in the early, intermediate and advanced stages of the SARS outbreak were analyzed and the phylogenetic tree was constructed with Lasergene, Clustal X, DNAman and Treeview. T cell antigen epitopes of S2 protein were predicted on the basis of Internet database.</p><p><b>RESULT</b>With the epidemic spread of SARS-CoV, the S2 genes of the virus tended to become stable. Homology of S2 genes of SARS-CoV isolated in advanced stage of the outbreak reached 99.9%. Prediction of T cell antigen epitope showed that mutation at the 57th amino acid effected T cell antigen epitope.</p><p><b>CONCLUSION</b>S2 gene of GD322 SARS-CoV is relatively stable during the epidemic spread of the virus, and mutation at the 57th amino acids of S2 protein may affect the T cell antigen epitope.</p>

Construction and identification of genomic cDNA subclones of dengue 2 virus NGC strain / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct the cDNA subclones spanning the entire genome of dengue 2 virus NGC strain for further construction of full-length infectious viral cDNA clone.</p><p><b>METHODS</b>Two pairs of primers were designed according to the restriction endonuclease sites in the viral genome of dengue 2 virus NGC strain. After viral RNA extraction from the brain of infected new-born mice, two parts of full-length viral cDNA were amplified by long RT-PCR and cloned into the vector pCR-XL-TOPO. The partial sequence of the recombinant plasmid was determined.</p><p><b>RESULTS AND CONCLUSION</b>Sequence analysis and digestion with restriction enzymes demonstrated that the two cDNA subclones were specific for dengue 2 virus NGC strain, suggesting the successful construction of the two cDNA subclones of dengue 2 virus NGC strain.</p>

Advances in the Infection of Human Parvovirus B19 / 微生物学通报

Increased recognition of human parvovirus B19,as a significant human pathogen has resulted in intensive researches to understand the pathogenesis of B19 infection,to elucidate the nature of Th1-mediated cellular immune response,to improve diagnostic strategy that is deployed to detect B19 infection and blood-product contamination,and to lay a foundation that should contribute to the development of an effective vaccine to prevent B19 infection.In this review,the biologic characteristics and the pathogenesis of human parvovirus B19,and B19-related manifestations as well as laboratory diagnostic methods for B19 infection were comprehensively discussed.