Cytokine response in Balb/c mice infected with Francisella tularensis LVS and the Pohang isolate

We investigated the immune response induced by the Francisella (F.) tularensis live vaccine strain (LVS) and the Pohang isolate. After the Balb/c mice were infected intradermally (i.d) with 2 × 10⁴ cfu of F. tularensis LVS and Pohang, respectively, their blood and organs were collected at different times; 0, 3, 6, 24, 72, 96, 120 and 168 h after infection. Using these samples, RT-PCR and ELISA analysis were carried out for the comparative study of the cytokines, including TNF-α, INF-γ, IL-2, IL-4, IL-10 and IL-12. In the Pohang-infected mice at 120 h, the liver showed a 53 times higher level of TNF-α and a 42 times higher level of IFN-γ than the respective levels at the early time points after infection. The levels of TNF-α and IFN-γ induced by LVS were 5 times lower than those induced by the Pohang isolate. Also, the organs from the Pohang-infected mice showed higher levels of TNF-α, IFN-γ, IL-10 and IL-12 than the levels in the LVS-infected mice. The blood from the Pohang-infected mice at 120 h revealed about a 40 times increased level of IFN-γ, and IL-10 was also increased by 4 times at 96 h compared to an early infection time point, while IL-4 was not induced during the whole infection period. These results suggest that F. tularensis may induce a Th1-mediated immune response to in vivo infection and the Pohang isolate has a higher capacity than the LVS to induce an acute immune response in Blab/c mice.     

Synergetic effects of oral administration of levamisole and Echinacea purpurea on immune response in Wistar rat

This research investigated the effects of levamisole and Echinacea purpurea (EP), separately and together on the immune response of the rat as a laboratory model. In this experiment, 40 male Wistar rats were obtained and divided into four groups (n = 10). These groups received normal saline (10 mg/kg), EP (500 mg/kg), levamisole (2 mg/kg) and EP (500 mg/kg) with levamisole (2 mg/kg) as oral gavages every day for a period of 4 weeks, respectively. After obtaining blood samples (at the end of each week), haematocrit (HCT), differential and total white blood cell (WBC) counts, phagocyte activity (number), total protein, albumin and globulins levels of samples were obtained. The results of the study showed that the gamma globulin level, WBC, neutrophil and monocyte counts and phagocyte activity increased significantly in comparison with normal saline group during the study. According to the results, each of the mentioned agents had a stimulant effect on the immune system separately and together on rats. In the group that received EP and levamisole simultaneously, these effects were synergistically increased. These compounds, by increasing the mentioned factors, will probably affect the immune system.     

国内紫锥菊免疫调节作用研究进展

紫锥菊属植物,是原产于美洲的一类菊科野生花卉。紫锥菊以其免疫调节作用闻名于世。近年来,国内引种成功,其各种药理作用在人类、畜牧业以及水产养殖业有了广泛的研究。综述国内紫锥菊免疫调节作用在不同行业的研究进展,为紫锥菊在国内的应用提供参考。     

紫锥菊多糖对鸡淋巴细胞体外增殖影响

为了评价紫锥菊多糖免疫增强效果,将4种浓度的紫锥菊多糖分别加入体外培养的鸡脾脏淋巴细胞中,培养44 h后,用MTT法测定淋巴细胞增殖变化。结果表明,4种浓度的紫锥菊多糖对鸡淋巴细胞均有促进增殖及协同的作用,其中在50-100μg/mL浓度范围内效果最为显著。     

Maturation of bone marrow-derived dendritic cells by a novel ��-glucan purified from Paenibacillus polymyxa JB115

We investigated the immunostimulatory effects of a novel β-glucan purified from Paenibacillus (P.) polymyxa JB115 on bone marrow-derived dendritic cells (DCs), a type of potent antigen-presenting cells. β-glucan isolated from P. polymyxa JB115 enhanced the viability and induced the maturation of DCs. β-glucan markedly increased the cytokine production of DCs and surface expression of DC markers. In addition, DCs treated with β-glucan showed a higher capacity to stimulate allogeneic spleen cell proliferation compared to those treated with medium alone. These results demonstrate the effect of β-glucan on DC maturation and may increase the use of β-glucan.     

紫锥菊提取物对大鼠湿热泄泻的疗效及其机制

本研究通过建立大鼠湿热泄泻模型,探讨紫锥菊提取物(EPE)对湿热泄泻大鼠的疗效,为紫锥菊提取物防治湿热泄泻提供科学依据。采用“内外湿热+大肠杆菌”建立大鼠湿热泄泻,分别给予1、3g·kg^-1剂量EPE治疗,采用临床症状评分评价疾病模型,测定各组大鼠血常规、血生化、血清炎性因子、脏器指数与结肠相关基因表达水平,并对大鼠器官进行病理组织学观察。结果表明,造模后大鼠被毛蓬松、精神萎靡,扎堆,懒动,眼周出现分泌物,大便溏泄,色黄恶臭,肛周污秽。给药6d后,高、低剂量EPE组与阳性药物组大鼠精神、饮食及临床表现均恢复正常。与空白组相比,模型组大鼠的心、脾、肺指数显著上升(P＜0.05),血液中红细胞数(RBC)、血红蛋白浓度(HGB)、红细胞压积(HCT)显著降低(P＜0.05);血清中尿素、丙氨酸氨基转移酶(ALT)水平显著降低(P＜0.05),IL-6、IL-17、IL-23水平显著上升(P＜0.05),TGF-β、IL-2、IL-10水平显著下降(P＜0.05);结肠TGF-β1与Foxp3 mRNA表达量显著下降(P＜0.05),RORγt mRNA表达显著上升(P＜0.05);心出现大面积出血瘀血,肝水肿,脾水肿及陈旧性出血,肾出现炎性细胞增生与蛋白尿的沉积。与模型组相比,高、低剂量EPE组的心指数、脾指数、肺指数显著降低(P＜0.05),血液HCT显著升高(P＜0.05),血清尿素、总胆固醇(TC)、总蛋白(TP)、白蛋白(ALB)水平显著升高(P＜0.05),血清IL-17、IL-23水平显著下降(P＜0.05),TGF-β水平显著上升(P＜0.05);结肠TGF-β1与Foxp3 mRNA表达显著上升(P＜0.05),RORγt mRNA表达显著下降(P＜0.05)。高、低剂量EPE组的脏器细胞损伤有所恢复。紫锥菊提取物能通过降低血脂、调节血清炎性因子水平及改善脏器功能以缓解大鼠湿热泄泻。     

不同紫锥菊提取物对肉仔鸡免疫功能影响

研究不同紫锥菊提取物对肉仔鸡免疫功能的影响。将270只1日龄肉仔鸡分为9组,通过测定肉仔鸡生长性能、免疫器官指数、血液生化指标、新城疫抗体滴度以及超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)的含量,探讨不同紫锥菊提取物对肉仔鸡体液免疫、细胞免疫和抗氧化能力的影响。结果显示,日粮中添加进口和康地恩紫锥菊提取物能够显著增加肉仔鸡的平均日增重,降低料重比,提高胸腺和法氏囊指数,并且能够显著改变肉仔鸡的白细胞数、红细胞数及红细胞压积,提高机体的抗氧化能力和新城疫抗体效价,优于万适宁、转移因子和紫锥疫毒清组;紫锥菊提取物组的作用效果均明显优于环磷酰胺组和环磷酰胺+康地恩紫锥菊提取物组,且环磷酰胺+康地恩紫锥菊提取物组的作用比环磷酰胺组好。表明紫锥菊提取物均能够显著增强肉仔鸡的免疫功能,康地恩紫锥菊提取物的总体免疫调节效果与进口紫锥菊提取物的效果一致,均优于国产紫锥菊提取物、万适宁、转移因子和紫锥疫毒清,并且康地恩紫锥菊提取物能够提高由于环磷酰胺引起的免疫水平下降。     

Response of whole blood, erythrocyte and plasma vitamin E content to dietary vitamin E intake in the chick

Whole blood, red blood cells (RBC), and plasma vitamin E (VE) levels in chicks fed dietary VE (dl-alpha-tocopheryl acetate, dl-alpha Ta) supplementation in steps of 0.0, 5.0, 10.0, 15.0, 20.0 and 30.0 mg/Kg were determined to examine their usefulness as an index of VE status. The increase in VE level was significant and linear in whole blood (r = 0.90), RBC (r = 0.89) and plasma (r = 0.93) in response to dietary VE intake. There was a close correlation between VE in plasma vs whole blood (r = 0.90), plasma vs RBC (r = 0.91) and whole blood vs RBC (r = 0.95). The plasma VE content was 1.2-1.8 times greater than that of whole blood, and 6.6-12.5 times greater than that of RBC. The plasma total lipids content was not affected by the dietary VE intake, whereas the level of VE in the plasma total lipids was significantly increased with increasing supplementation. Alpha tocopherol was the major isomer (ca 92%) of VE in whole blood, RBC and plasma at hatching. The small proportions of beta-tocopherol (ca 2%), gamma-tocopherol (ca 5%) and alpha-tocotrienol (ca 1%) observed at 1 day of age had decreased or totally disappeared by 7 days of age after feeding the VE-free basal diet. The data showed that in the chick, the whole blood and RBC levels of VE were as sensitive and reliable indexes of dietary VE status as was that of the plasma.     

Evidence for estrogen receptor expression during medullary bone formation and resorption in estrogen-treated male Japanese quails (Coturnix coturnix japonica)

The temporal expression of estrogen receptor (ER)-α and ER-β mRNA was examined in male Japanese quails. Femurs of quails receiving 17β-estradiol underwent RTPCR and histochemical analysis 1 to 15 days after treatment. Untreated quails were used as controls (day 0). Between days 0 and 5, cells lining the bone endosteal surface differentiated into osteoblasts, which in turn formed medullary bone. Expression of ER-α was already observed on day 0 and increased slightly during bone formation whereas ER-β was hardly detected throughout this process. After osteoclasts appeared on the medullary bone surface, this type of bone disappeared from the bone marrow cavity (days 7~15). ER-α expression simultaneously decreased slightly and ER-β levels remained very low. These results suggest that estrogen activity mediated by ER-α not only affects medullary bone formation but also bone resorption.     

Myeloid differentiation factor 88 is required for resistance to Neospora caninum infection

Neospora caninum is an intracellular parasite that causes major economic impact on cattle raising farms, and infects a wide range of warm-blooded hosts worldwide. Innate immune mechanisms that lead to protection against this parasite are still unknown. In order to investigate whether myeloid differentiation factor 88 (MyD88) is required for resistance against N. caninum, genetically deficient mice (MyD88^−/−) and wild type littermates were infected with live tachyzoites and the resistance to infection was evaluated. We found that sub-lethal tachyzoite doses induced acute mortality of MyD88^−/− mice, which succumbed to infection due to uncontrolled parasite replication. Higher parasitism in MyD88^−/− mice was associated with the lack of IL-12 production by dendritic cells, delayed IFN-γ responses by NKT, CD4⁺ and CD8⁺ T lymphocytes, and production of high levels of IL-10. MyD88^−/− mice replenished with IL-12 and IFN-γ abolished susceptibility as the animals survived throughout the experimental period. We conclude that protective IFN-γ-mediated immunity to N. caninum is dependent on initial MyD88 signaling, in a mechanism triggered by production of IL-12 by dendritic cells. Further knowledge on Toll-like receptor recognition of N. caninum antigens is encouraged, since it could generate new prophylactic and therapeutic tools to control parasite burden.     

A novel ��-glucan produced by Paenibacillus polymyxa JB115 induces nitric oxide production in RAW264.7 macrophages

The effect of extracellular β-(1→3), (1→6)-glucan, produced by Paenibacillus polymyxa JB115, on nitric oxide (NO) production in RAW264.7 macrophages was investigated. β-glucan induced the production of NO by RAW264.7 macrophages in a concentration- and time-dependent manner. Moreover, β-glucan stimulation increased the mRNA expression of iNOS, COX-2 and IL-6 in RAW264.7 macrophages in a concentration-dependent manner.     

Anti-obesity activity of diglyceride containing conjugated linoleic acid in C57BL/6J ob/ob mice

This study was to investigate the anti-obesity effects of diglyceride (DG)-conjugated linoleic acid (CLA) containing 22% CLA as fatty acids in C57BL/6J ob/ob male mice. There were four experimental groups including vehicle control, DG, CLA, and DG-CLA. The test solutions of 750 mg/kg dose were orally administered to the mice everyday for 5 weeks. CLA treatments significantly decreased mean body weight in the obese mice throughout the experimental period compared to the control (p < 0.01). All test solutions significantly decreased the levels of triglyceride, glucose and free fatty acids in the serum compared with control (p < 0.05). The levels of total cholesterol were also significantly reduced in DG and DG-CLA groups compared with the control group (p < 0.05). CLA significantly decreased weights of renal and epididymal fats compared with the control (p < 0.05). DG and DG-CLA also significantly decreased the epididymal fat weights compared with the control (p < 0.05). A remarkable decrease in the number of lipid droplets and fat globules was observed in the livers of mice treated with DG, CLA, and DG-CLA compared to control. Treatments of DG and CLA actually increased the expression of peroxisome proliferator-activated receptor gamma. These results suggest that DG-CLA containing 22% CLA have a respectable anti-obesity effect by controlling serum lipids and fat metabolism.     

N -ethyl- N -nitrosourea induces retinal photoreceptor damage in adult rats

Seven-week-old male Lewis rats received a single intraperitoneal injection of N-ethyl-N-nitrosourea (ENU) (100, 200, 400 or 600 mg/kg), and retinal damage was evaluated 7 days after the treatment. Sequential morphological features of the retina and retinal DNA damage, as determined by a TUNEL assay and phospho-histone H2A.X (γ-H2AX), were analyzed 3, 6, 12, 24 and 72 hr, 7 days, and/or 30 days after 400 mg/kg ENU treatment. Activation of the nuclear enzyme poly (ADP-ribose) polymerase (PARP) was analyzed immunohistochemically by poly (ADP-ribose) (PAR) expression in response to DNA damage of the retina. All rats that received ≥ 400 mg/kg of ENU developed retinal degeneration characterized by the loss of photoreceptor cells in both the central and peripheral retina within 7 days. In the 400 mg/kg ENU-treated rats, TUNEL-positive signals were only located in the photoreceptor cells and peaked 24 hr after ENU treatment. The γ-H2AX signals in inner retinal cells appeared at 24 hr and peaked at 72 hr after ENU treatment, and the PAR signals selectively located in the photoreceptor cell nuclei appeared at 12 hr and peaked at 24 hr after ENU treatment. However, degeneration was restricted to photoreceptor cells, and no degenerative changes in inner retinal cells were seen at any time points. Retinal thickness and the photoreceptor cell ratio in the central and peripheral retina were significantly decreased, and the retinal damage ratio was significantly increased 7 days after ENU treatment. In conclusion, ENU induced retinal degeneration in adult rats that was characterized by photoreceptor cell apoptosis through PARP activity.     

High Prevalence of BlaCTX-M Group Genes in Aeromonas dhakensis Isolated from Aquaculture Fish Species in South Korea

The prevalence of resistant genes against β-lactams in 119 Aeromonas strains was determined. A large number (99.2%) of the present fish strains were resistant to one or more β- lactams including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of A. dhakensis, 8 strains of A. caviae, 2 strains of A. hydrophila and only one strain of A. veronii. For exploring genetic background of the antibiotic resistances, multiple PCR assays were subjected to detect β-lactamase-encoding genes, bla_TEM, bla_OXA-B and bla_CTX-M. In the results, the bla_TEM-1 gene was harbored in all strains, whereas only 3 strains harbored bla_OXA gene. In the case of bla_CTX-M gene, the gene was detected in 21.0% (25 out of 119) of all strains, which countered with 80% (20 out of 25) of A. dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25) of A. hydrophila. In addition, most of the bla_CTX-M positive strains showed simultaneous resistance to all β-lactams (18 out of 30 strains). In sequence analysis for bla_CTX-M genes detected, they were CTX-M group 1-encoding genes including bla_CTX-M-33 from 3 eel strains of A. dhakensis. Therefore, A. dhakensis obtained from cultured fish could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence should be carefully monitored, especially for its potential risk to public health.     

Serum-gamma-glutamyltranspeptidase (gamma-GT) and aspartate-aminotransferase (AspAT) activities in adult cattle with chronic Fasciola hepatica infection

Sera from adult cattle with fluke-infected and normal livers were analyzed for γ-GT and AspAT activities. The analyses revealed no significant increases in either γ-GT or AspAT values of the animals with fascioliasis as compared with the non-infected animals. The advanced chronic stage of the infection characterized by hepatic fibrosis, limited injury of parenchyma and low fluke burdens may explain the lack of enzymatic increase.     

Prolonged expression of senescence markers in mice exposed to gamma-irradiation

Although ionizing radiation is known to induce cellular senescence in vitro and in vivo, its long-term in vivo effects are not well defined. In this study, we examined the prolonged expression of senescence markers in mice irradiated with single or fractionated doses. C57BL/6 female mice were exposed to 5 Gy of γ-rays in single or 5, 10, 25 fractions. At 2, 4, and 6 months after irradiation, senescence markers including mitochondrial DNA (mtDNA) common deletion, p21, and senescence-associated β-galactosidase (SA β-gal) were monitored in the lung, liver, and kidney. Increases of mtDNA deletion were detected in the lung, liver, and kidney of irradiated groups. p21 expression and SA β-gal staining were also increased in the irradiated groups compared to the non-irradiated control group. Increases of senescence markers persisted up to 6 months after irradiation. Additionally, the extent of mtDNA deletion and the numbers of SA β-gal positive cells were greater as the number of radiation fractions increased. In conclusion, our results showed that ionizing radiation, especially that delivered in fractions, can cause the persistent upregulation of senescence marker expression in vivo. This should be considered when dealing with chronic normal tissue injuries caused by radiation therapy or radiation accidents.     

Control of Mycobacterium bovisinfection in two sika deer herds in Ireland

In a number of countries, tuberculosis (due to infection with Mycobacterium bovis) is a significant health problem of captive deer. This paper describes outbreaks of bovine tuberculosis in sika deer (Cervus nippon) on two farms in Ireland and the methods used to control the disease. On Farm A, infection was first detected during 1993. The infection was eradicated using a programme of test and removal, in association with segregation of young animals. A second outbreak (also due to infection with M. bovis, but a different RFLP profile) was detected in 2002. In the latter outbreak, infection was particularly prevalent in two groups of young deer. M. bovis with the same RFLP profile was also isolated in a badger found dead on the farm. Control was achieved by test and removal in association with herd management changes. In Herd B, infection was first detected in 1995, and subsequently eradicated using test and removal alone. In Herd A, re-infection remains an ongoing risk. Control rather than eradication of infection may more realistic in the short-to medium-term.     

GC/MS analysis of high-performance liquid chromatography fractions from Sophora flavescens and Torilis japonica extracts and their in vitro anti-neosporal effects on Neospora caninum

We analyzed alcoholic extracts of herbs possessing anti-neosporal activity against Neospora (N.) caninum. To identify the chemical components of Sophora (S.) flavescens and Torilis (T.) japonica associated with anti-neosporal activity, specific fractions were isolated by high-performance liquid chromatography (HPLC). In vitro activity of the fractions against N. caninum was then assessed. Gas chromatography/mass spectrometry (GC/MS) was used to identify and quantify specific anti-neosporal molecules in the herbal extracts. Almost all HPLC fractions of S. flavescens and T. japonica had higher levels of anti-neosporal activity compared to the not treated control. Active constituents of the extracts were sophoridane, furosardonin A, and tetraisopropylidene-cyclobutane in S. flavescens; 5,17-β-dihydroxy-de-A-estra-5,7,9,14-tetraene, furanodiene, and 9,12-octadecadienoic acid (Z,Z)-(CAS,1) in T. japonica.     

Phylogenetic groups and cephalosporin resistance genes of Escherichia coli from diseased food-producing animals in Japan

A total of 318 Escherichia coli isolates obtained from different food-producing animals affected with colibacillosis between 2001 and 2006 were subjected to phylogenetic analysis: 72 bovine isolates, 89 poultry isolates and 157 porcine isolates. Overall, the phylogenetic group A was predominant in isolates from cattle (36/72, 50%) and pigs (101/157, 64.3%) whereas groups A (44/89, 49.4%) and D (40/89, 44.9%) were predominant in isolates from poultry. In addition, group B2 was not found among diseased food-producing animals except for a poultry isolate. Thus, the phylogenetic group distribution of E. coli from diseased animals was different by animal species. Among the 318 isolates, cefazolin resistance (minimum inhibitory concentrations: ≥32 μg/ml) was found in six bovine isolates, 29 poultry isolates and three porcine isolates. Of them, 11 isolates (nine from poultry and two from cattle) produced extended spectrum β-lactamase (ESBL). The two bovine isolates produced bla_CTX-M-2, while the nine poultry isolates produced bla_CTX-M-25 (4), bla_SHV-2 (3), bla_CTX-M-15 (1) and bla_CTX-M-2 (1). Thus, our results showed that several types of ESBL were identified and three types of β-lactamase (SHV-2, CTX-M-25 and CTX-M-15) were observed for the first time in E. coli from diseased animals in Japan.     

Cytotoxicity of gamma-ray in rat immature hippocampal neurons

This in vitro study evaluated the detrimental effect of acute gamma (γ)-irradiation on rat immature hippocampal neurons. Rat immature hippocampal neurons (0.5 day in vitro) were irradiated with 0~4 Gy γ-rays. Cytotoxicity was analyzed using a lactate dehydrogenase release assay at 24 h after γ-irradiation. Radiation-induced cytotoxicity in immature hippocampal neurons increased in a dose-dependent manner. Pre-treatments of pro-apoptotic caspase inhibitors and anti-oxidative substances significantly blocked γ-irradiation-induced cytotoxicity in immature hippocampal neurons. The results suggest that the caspase-dependent cytotoxicity of γ-rays in immature hippocampal cultured neurons may be caused by oxidative stress.