Effects of puerarin on lipopolysaccharide-induced myocardial dysfunction in isolated rat hearts.

Myocardial dysfunction is a serious complication induced by sepsis. Puerarin is an oriental medicine that possesses therapeutic benefits for cardiovascular diseases. The aim of this study was to evaluate the anti-myocardial dysfunction effects of puerarin in isolated rat hearts induced by lipopolysaccharide- and compare the myocardial protective effects between the different concentrations of puerarin. Isolated hearts were attached to a Langendorff apparatus and perfused with lipopolysaccharide (LPS) and different concentrations of puerarin. The hemodynamic parameters of heart rate (HR), left ventricular end systolic pressure [LVESP], +dp/dtmax, and -dp/dtmax were recorded. The biochemical indexes of lactic dehydrogenase (LDH), tumor necrosis factor alpha (TNF-α), and creatine kinase (CK) in the coronary effluent were measured at 40, 90, and 120 min of perfusion. TNF-α in myocardial tissues was measured after perfusion was completed. As a result, puerarin (0.24 µmmol/L-0.48 µmmol/L) significantly increased LVESP, +dp/dtmax, -dp/dtmax, and HR in isolated rat hearts that were declined by LPS during perfusion periods. Puerarin could protect against increased LDH, CK, and TNF-α in coronary effluent of isolated rat hearts by LPS during perfusion periods. Treatment of 0.48 µmmol/L puerarin significantly decreased the TNF-α in coronary effluent of isolated rat hearts compared with the treatment of 0.12 and 0.24 µmmol/L puerarin, but the TNF-α values were not reverted to baseline levels. However, the difference of TNF-α in myocardial tissue in the three puerarin-combined groups was statistically significant. This study confirms that puerarin can improve LPS-induced contractile dysfunction in isolated heart and inhibit LPS-stimulated myocardial TNF-α production.

Localized expression of human BMP-7 by BM-MSCs enhances renal repair in an in vivo model of ischemia-reperfusion injury.

Ischemia and subsequent reperfusion (I/R) damage kidney tubular cells and consequently impair renal function. Rabbit bone marrow mesenchymal stem cells (BM-MSCs) expressing human bone morphogenic protein-7 (hBMP-7) regenerated tubular cells and improved renal function in a kidney I/R model. Rabbits were injected immediately after I/R with one of the following: (i) hBMP-7-transduced BM-MSCs (BM-MSCshBMP-7); (ii) enhanced green fluorescent protein-transduced BM-MSCs (BM-MSCsEGFP); or (iii) PBS. The activity of superoxide dismutase (SOD) was higher, and the amount of malondialdehyde (MDA) was lower in the BM-MSCshBMP-7 group than in the BM-MSCsEGFP group. Both the BM-MSCshBMP-7 group and the BM-MSCsEGFP group had higher SOD activity and lower amounts of MDA than the PBS group. Bcl-2- and Bcl-2-associated X protein levels, and other variables, indicated the regeneration of the kidney in both experimental groups. However, the BM-MSCs (hBMP-7) group showed higher activity than the BM-MSCsEGFP group, indicating that the combined strategy of BM-MSC transplantation with hBMP-7 gene therapy could be a useful approach for the treatment of renal IRI.

Distribution characteristics of soil microbial communities and their responses to environmental factors in the sea buckthorn forest in the water-wind erosion crisscross region.

Soil microorganisms are an important part of forest ecosystems, and their community structure and ecological adaptations are important for explaining soil material cycles in the fragile ecological areas. We used high-throughput sequencing technology to examine the species composition and diversity of soil bacterial and fungal communities in sea buckthorn forests at five sites in the water-wind erosion crisscross in northern Shaanxi (about 400 km long). The results are described as follows: (1) The soil bacterial community of the sea buckthorn forest in the study region was mainly dominated by Actinobacteria, Proteobacteria, and Acidobacteria, and the fungi community was mainly dominated by Ascomycota. (2) The coefficient of variation of alpha diversity of microbial communities was higher in the 0-10 cm soil layer than in the 10-20 cm soil layer. (3) Soil electrical conductivity (36.1%), available phosphorous (AP) (21.0%), available potassium (16.2%), total nitrogen (12.7%), and the meteorological factors average annual maximum temperature (33.3%) and average annual temperature (27.1%) were identified as the main drivers of structural changes in the bacterial community. Available potassium (39.4%), soil organic carbon (21.4%), available nitrogen (AN) (13.8%), and the meteorological factors average annual maximum wind speed (38.0%) and average annual temperature (26.8%) were identified as the main drivers of structural changes in the fungal community. The explanation rate of soil factors on changes in bacterial and fungal communities was 26.6 and 12.0%, respectively, whereas that of meteorological factors on changes in bacterial and fungal communities was 1.22 and 1.17%, respectively. The combined explanation rate of environmental factors (soil and meteorological factors) on bacterial and fungal communities was 72.2 and 86.6%, respectively. The results of the study offer valuable insights into the diversity of soil microbial communities in the water-wind erosion crisscross region and the mechanisms underlying their interaction with environmental factors.

Identification of proteoglycans as the APRIL-specific binding partners.

B cell activating factor of the tumor necrosis factor (TNF) family (BAFF) and a proliferation-inducing ligand (APRIL) are closely related ligands within the TNF superfamily that play important roles in B lymphocyte biology. Both ligands share two receptors--transmembrane activator and calcium signal--modulating cyclophilin ligand interactor (TACI) and B cell maturation antigen (BCMA)--that are predominantly expressed on B cells. In addition, BAFF specifically binds BAFF receptor, whereas the nature of a postulated APRIL-specific receptor remains elusive. We show that the TNF homology domain of APRIL binds BCMA and TACI, whereas a basic amino acid sequence (QKQKKQ) close to the NH2 terminus of the mature protein is required for binding to the APRIL-specific "receptor." This interactor was identified as negatively charged sulfated glycosaminoglycan side chains of proteoglycans. Although T cell lines bound little APRIL, the ectopic expression of glycosaminoglycan-rich syndecans or glypicans conferred on these cells a high binding capacity that was completely dependent on APRIL's basic sequence. Moreover, syndecan-1-positive plasma cells and proteoglycan-rich nonhematopoietic cells displayed high specific, heparin-sensitive binding to APRIL. Inhibition of BAFF and APRIL, but not BAFF alone, prevented the survival and/or the migration of newly formed plasma cells to the bone marrow. In addition, costimulation of B cell proliferation by APRIL was only effective upon APRIL oligomerization. Therefore, we propose a model whereby APRIL binding to the extracellular matrix or to proteoglycan-positive cells induces APRIL oligomerization, which is the prerequisite for the triggering of TACI- and/or BCMA-mediated activation, migration, or survival signals.

[Inhibition of Toxoplasma gondii excretory - secretory antigens on growth of murine Lewis lung carcinoma].

OBJECTIVE: To investigate the effect of Toxoplasma gondii excretory-secretory antigens (ESA) on CD4+ CD25+ Foxp3+ T (Treg) cells in mice carrying Lewis lung carcinoma, and examine the inhibitory effect of T. gondii ESA on tumor growth. METHODS: C57BL/6 mice were randomly assigned into the PBS group (n = 14) and the Lewis group (n = 34). Mice in the Lewis group were subcutaneously injected with 2 × 105 Lewis lung carcinoma cells in the right axilla, while animals in the PBS group were injected with the same volume of sterile PBS. On day 7 post-injection (D7), mice in the PBS group were further divided into the PBS2 group and the PBS2 + ESA group, of 7 mice in each group, and mice in the Lewis group were further divided into the Lewis2 group and the Lewis2 + ESA group, of 17 mice in each group. Then, mice in the PBS2 + ESA group and the Lewis2 + ESA group were intraperitoneally injected with 100 µL of ESA. The mouse spleen coefficient was calculated in each group 7 days post-injection with ESA, and the changes of Treg cell counts and the long-term tumor growth were measured in tumor-bearing mice. RESULTS: The spleen coefficient was significantly greater in the PBS2 + ESA group and the Lewis2 + ESA group than in the PBS2 (0.66% ± 0.09% vs. 0.30% ± 0.02%, P < 0.05) and Lewis2 groups (0.69% ± 0.07% vs. 0.33% ± 0.03%, P < 0.05) 7 days post-treatment with ESA, respectively, and the percentage of splenic Treg cells in splenocytes was significantly lower in the PBS2 + ESA group and the Lewis2 + ESA group than in the PBS2 (1.28% ± 0.14% vs. 2.06% ± 0.07%, P < 0.05) and Lewis2 groups (1.58% ± 0.14% vs. 2.44% ± 0.23%, P < 0.05), respectively. T. gondii ESA treatment caused a delay in tumor growth, and the tumor size was significantly smaller in the Lewis2 + ESA group than in the Lewis2 group (P < 0.05). CONCLUSIONS: T. gondii ESA may reduce the proportion of splenic Treg cells in splenocytes and inhibit tumor growth in mice carrying Lewis lung carcinoma.

[Effect of cystatin from Schistosoma japonicum on DSS - induced ulcerative colitis in mice].

OBJECTIVE: To investigate the effect of cysteine protease inhibitor derived from Schistosoma japonicum (SjCystatin) on dextran sodium sulfate (DSS)-induced acute ulcerative colitis in mice. METHODS: Eighteen C57BL/6 mice were randomly divided into three groups: a control group treated with PBS (Group A), a DSS-induced-colitis group treated with PBS (Group B), and a DSS-induced-colitis group treated with SjCystatin (Group C). Colitis was induced in mice by giving 3% DSS orally for 7 days. During this period, the mice were daily injected with 10 µg of SjCystatin or PBS only as a control intraperitoneally. The mice were monitored daily for their clinical manifestations and given scores based on disease activity index (DAI). The severity of colonic inflammation was monitored by the macroscopic score and pathological change. The cytokine profile including TNF-α, IL-4, IL-6 and IL-10 in the supernatants of colon homogenate was detected by ELISA. RESULTS: Compared with Group A (0.50 ± 0.28), the DAI score increased significantly in Group B (9.30 ± 1.30) (F = 86.86, P < 0.01), with remarkable pathological damages seen in colon tissues. and the levels of TNF-α and IL-6 were (321.33±67.01) and (403.58 ±180.51) pg/mL. The DAI score significantly reduced in Group C (6.67±1.57) as compared to Group B (F = 86.86, P < 0.01), with improvements in the macroscopic and microscopic pathology in mouse colon specimens. As compared to Group B, the levels of TNF-α [(188.14 ± 40.14) pg/mL] and IL-6 ([ 209.71 ± 48.47) pg/mL] significantly decreased (F = 17.46 and 9.89, both P < 0.01). CONCLUSIONS: SjCystatin has a significantly inhibitory effect for alleviating DSS-induced acute ulcerative colitis in C57BL/6 mice.

[Anti-tumor effect of Plasmodium yoelii infection on melanoma in mice].

OBJECTIVE: To explore the anti-tumor effect of 17XL strains of Plasmodium yoelii (P.y) infection on melanoma in mice. METHODS: B16F10 tumor cells were axillarilly injected into the right flank of 20 C57BL/6 mice to establish tumor-bearing mouse models. The next day, the mice were randomly divided into a P.y infection group and control group, 10 mice each group. Each mouse of the P.y infection group was intraperitoneally injected with 1×106 red blood cells including 20% P.y infection red blood cells, and each one of the control group were intraperitoneally injected with 1×106 normal red blood cells of C57BL/6 mice. The time of tumor formation of the mice in the two groups was observed and the tumor volumes were measured. RESULTS: The time of tumor formation in the P.y infection groupï¼» (11.30 ± 0.21) dï¼½was significantly later than that in the control group ï¼» (10.40 ± 0.22) dï¼½ (P < 0.05). From the tumors could be accurately measured to the study end point, both the tumors of mice in the two groups were growing, and the tumor volumes of mice in the P.y infection group were significantly less than those in the control group at each time point (all P < 0.05). The growth rate of tumors in the P.y infection group ï¼» (71.10 ± 6.29) mm3/dï¼½ was significantly slower than that in the control group ï¼» (302.80 ± 49.94) mm3/dï¼½ (P < 0.05), and the growth rates of tumors everyday in the P.y infection group were significantly slower than those in the control group (all P < 0.05). CONCLUSIONS: The P.y infection can delay the occurrence of tumor and inhibit the growth of melanoma.

[Experience and analysis of excellent works of human parasitology in national medical colleges and universities].

Teaching competition is an effective way for college and university teachers to improve their teaching skills. Based on the teaching practice and experience in medical parasitology, this paper discusses several key issues in teaching competition including topics, teaching designs and teaching methods. It provides references for the teachers in department of parasitology of universities and colleges to improve the quality of classroom teaching.

Surface electromyography based muscle fatigue analysis for stroke patients at different Brunnstrom stages.

Muscle fatigue analysis has been an important topic in sport and rehabilitation medicine due to its role in muscle performance evaluation and pathology investigation. This paper proposes a surface electromyography (sEMG) based muscle fatigue analysis approach which was specifically designed for stroke rehabilitation applications. 14 stroke patients from 5 different Brunnstrom recovery stage groups were involved in the experiment and features including median frequency and mean power frequency were extracted from the collected sEMG samples for investigation. After signal decomposition, the decline of motor unit firing rate of patients from different groups had also been studied. Statistically significant presence of fatigue had been observed in deltoideus medius and extensor digitorum communis of patients at early recovery stages (P<;0.05) and no similar observation had been obtained for patients at later stages (P>0.01). It had also been discovered that the motor unit firing frequency declines with a range positively correlated to the recovery stage during repetitive movements. Based on the experiment result, it can be verified that as the recovery stage increases, the central nervous system's control ability strengthens and the patient motion becomes more stable and resistive to fatigue.

[Multiple insecticide resistances and kdr mutation of Culex pipiens pallens in north-central Anhui Province].

OBJECTIVE: To understand the status of resistance to multiple insecticides and the frequencies of kdr mutations in Culex pipiens pallens from north-central Anhui Province. METHODS: From July to September, 2014, the C. pipiens pallens mosquito larvae were collected in Huaibei, Bengbu and Chuzhou cities of the north-central Anhui Province and reared to adults. The female adult mosquitoes at 3-5 days post emergence were tested for susceptibility to the four insecticides, namely 0.05% deltamethrin, 5% malathion, 0.1% bendiocarb and 4% DDT, by using the standard WHO resistance tube bioassay. The detection of the point mutations of the kdr gene at codon 1014 was conducted by PCR and DNA sequencing in the deltamethrin-resistant and -susceptible mosquitoes. RESULTS: High levels of resistance to all the four insecticides were found in all the three tested populations, although mosquito mortality varied among populations and test insecticides. Among the test insecticides, DDT showed lowest mortality with no significant difference (F = 1.027, P > 0.05) in all test populations, whereas significantly different mortalities were observed among populations for the remained three insecticides tested (deltamethrin, malathion, and bendiocarb) (F = 23.823, 33.955, 128.841; all P < 0.01). Two types of non-synonymous kdr mutation at codon position 1014 (L1014F and L1014S) were observed. A positive correlation between L1014F mutation frequencies and deltamethrin resistance levels were detected in the three mosquito populations (r2 = 0.718, P < 0.01). CONCLUSIONS: The observed high levels of resistance to multiple-insecticides coupled with the occurrence of medium to high kdr frequencies in populations of C. pipiens pallens could profoundly affect the mosquito vector control programme in China. The local health departments need to strengthen vector dynamic monitoring and implement rational resistance management strategies.

[Effect of exogenous nitric oxide on antioxidants from mice infected with Trichinella spiralis].

OBJECTIVE: To study the effect of exogenous nitric oxide donor sodium nitroprusside (SNP) on antioxidant enzymes activities and lipid peroxidation of mice infected with Trichinella spiralis. METHODS: BALB/c mice were infected with T. spiralis separated by the digestion method. Forty-two days post-infection, the peripheral blood and hepatic tissue from the infected or normal mice were collected. Then 4 groups were set：liver homogenate from infected mice + SNP (Group A), liver homogenate from normal mice + SNP (Group B), peripheral blood from infected mice + SNP (Group C), and peripheral blood from normal mice + SNP (Group D). The final concentrations of SNP in each group were set as 0 (blank control), 2, 5, 10 µmol/L and 30 µmol/L, respectively. After reacting with SNP at 37 ℃ for 30 min, the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) activities, and malondialdehyde (MDA) concentration were examined and compared. RESULTS: The levels of SOD, CAT, GSH-Px and MDA concentration in the liver and the blood from the mice infected with T. spiralis were significantly higher than those of the normal ones (all P < 0.05). When reacted with 10 µmol/L and 30 µmol/L SNP, the SOD, GSH-Px, and CAT activities in Group A and B decreased significantly (all P < 0.05), while the liver MDA concentration reacted with 2-30 µmol/L SNP increased obviously (all P < 0.05). As reacted with 30 µmol/L SNP, the activities of blood SOD, GSH-Px, and CAT in Group C and D decreased, while the MDA concentration in blood still increased (all P < 0.01). When the SNP concentration was in the range of 2-30 µmol/L, there were a negative correlation between the SNP concentrations and SOD, GSH-Px, and CAT activities, as well as a positive correlation with the MDA concentration in the liver and blood from the mice infected with T. spiralis (all P < 0.05). CONCLUSIONS: T. spiralis infection could cause oxidative damage to mice, and increase SOD, GSH-Px, and CAT activities. Nitric oxide released from SNP can decrease antioxidase activities, and inhibit the antioxidant capacity of mice infected with T. spiralis.

[Effect of excretory/secretory protein of Trichinella spiralis adult worm on CLP-induced sepsis in mice].

OBJECTIVE: To observe the effect of excretory/secretory products from Trichinella spiralis adult worms (AES) on cecal ligation and puncture (CLP) -induced sepsis in mice. METHODS: Forty-eight BALB/c mice were randomly divided into 3 groups：a sham operation group (PBS + sham group, Group A), a CLP-induced sepsis group (PBS+CLP group, Group B) and an AES treatment group (AES+CLP group, Group C). The mice of each group were intraperitoneally injected with 25 µg of AES or PBS only as a control in a total volume of 200 µl. Eight mice from each group were selected randomly for survival analysis of 96 hours. The other 8 mice in each group were observed for pathological changes in the lung, liver and kidney tissues by HE staining 12 h after CLP, and then determined for the detection of cytokines including TNF-α, IL-1ß, IL-6, IL-10 and TGF-ß in the sera by ELISA. RESULTS: The difference among the survival rates of mice in the 3 groups was statistically significant (χ2 = 21.16, P < 0.05). Compared to Group A (100%), the survival rate of mice in Group B (0) decreased significantly (P < 0.05), and also the pathological damage degrees in the lung, liver and kidney tissues of the mice in Group B increased significantly after CLP. Compared with the mice in group B, the survival rate of those in Group C (70%) increased significantly (P < 0.05), and the pathological damage degrees in the lung, liver and kidney tissues of the mice in Group C decreased significantly after the treatment with AES. The differences among the levels of pro-inflammatory cytokines TNF-α (F = 27.11, P < 0.05), IL1ß (F = 18.75, P < 0.05) and IL-6 (F = 100.93, P < 0.05) in the sera of the mice in the three groups were statistically significant. Compared with the mice in Group A, the levels of the 3 cytokines of those in Group B increased significantly (all P < 0.05). However, after the treatment with AES, the levels of the pro-inflammatory cytokines of those in Group C decreased significantly (all P < 0.05). The differences among the levels of immunoregulatory cytokines IL-10 (F = 10.88, P < 0.05) and TGF-ß (F = 11.37, P < 0.05) in the sera of the mice in the three groups were also statistically significant. Compared with the mice in Group B, the levels of IL-10 and TGF-ß of those in Group C were higher after treatment with AES (both P < 0.05). CONCLUSIONS: T. spiralis AES has a therapeutic potential for alleviating sepsis induced by CLP in mice.

Multidrug resistance in primary tumors and metastases in patients with esophageal squamous cell carcinoma.

Studies have demonstrated that radical esophagectomy can significantly prolong disease-free survival and improve the survival rate of patients with T3 or T4 esophageal cancer and lymph node metastasis. Multidrug resistant cancer cells have active efflux mechanisms that prevent the accumulation of chemotherapeutic drugs in the cells. The purpose of this study was to compare the expression of five MDR related proteins between primary tumors in patients with thoracic esophageal squamous cell carcinoma (ESCC) and metastatic cancer in lymph nodes to explore the clinical significance of heterogeneity in MDR metastatic cancer cells. Fifty-four patients with ESCC and lymph node metastasis were included. All patients underwent subtotal esophagectomy and D2/D3 lymph node resection. The expression of lung resistance-related protein (LRP), P-glycoprotein, topoisomerase-II, thymidylate synthase, and glutathione S-transferase P1-1 (GST-π) were determined in the primary tumors and lymph nodes via immunohistochemistry. The expression of LRP was significantly different between the primary tumors and lymph nodes (P = 0.026). No significant differences were found for the other four proteins, and protein expression was not associated with either degree of differentiation or disease stage. It was also found that GST-π was expressed in all patients in both the primary tumors and lymph nodes, suggesting that the design and application of chemotherapeutic protocols capable of reducing GST-π expression may be beneficial for patients with ESCC. Additional research regarding the clinical utility of MDR protein expression in ESCC is warranted to design effective chemotherapeutic protocols.