脱氧雪腐镰刀菌烯醇诱导CTLL-2细胞凋亡的信号途径研究

为探讨脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)对动物免疫功能的影响及其机理,以细胞毒性T淋巴细胞株CTLL-2为材料,用不同浓度的DON(0、0.5、1、2μg/m L)处理CTLL-2细胞48h,流式细胞术检测细胞的凋亡率,免疫印记法检测细胞凋亡相关通路蛋白CleavedCaspase 9、Cleaved-Caspase 3、Fas L、Fas、Cleaved-Caspase8等表达情况;并用流式细胞术检测了DON(1μg/m L)与Fas L中和抗体(10μg/m L)共处理后细胞的凋亡率。结果表明,随着DON浓度的升高,CTLL-2细胞的凋亡率呈上升趋势,染毒组均较对照组有极显著差异(P0.01);Bax/Bcl-2的比值升高,呈剂量-效应关系;DON促进细胞色素c(Cyt-c)从线粒体中释放到胞浆中,能够上调Cleaved-Caspase 9、Cleaved-Caspase 3的表达,染毒组均较对照组有显著性或极显著差异(P0.05或P0.01);Fas L、Fas、Cleaved-Caspase 8蛋白表达量随着DON浓度的升高逐渐增加,染毒组均较对照组有显著性或极显著差异(P0.05或P0.01);随着DON浓度的升高,p38 MAPK、JNK、Erk的磷酸化水平也升高,呈剂量-效应关系;与DON处理组相比,Fas L中和抗体与DON共同处理组细胞凋亡率明显下降(P0.01)。结果表明,DON可以诱导CTLL-2细胞发生凋亡,激活CTLL-2细胞线粒体通路、MAPKs通路,DON通过死亡受体途径诱导CTLL-2细胞凋亡,影响动物的免疫机能。     

伏马毒素B_1对人脐静脉血管内皮细胞的毒性作用研究

为探究伏马毒素B_1(FB_1)对人脐静脉血管内皮细胞(HUVEC)的毒性及作用机制,采用不同质量浓度的FB_1处理HUVEC,通过CCK-8法检测细胞活力,流式细胞术检测细胞周期,荧光显微镜观察细胞氧化应激,流式细胞术检测线粒体膜电位变化,Hoechst33342染色检测细胞凋亡,荧光定量PCR检测细胞凋亡相关基因的转录情况。结果显示:FB_1处理组在低质量浓度(2.5、5μg·mL~(-1))短时间(6、12h)处理后细胞活力变化不显著,超过此剂量和时间细胞活力显著降低(P0.05或P0.01),且质量浓度为10、20μg·mL~(-1) FB_1处理组活性氧(ROS)的荧光信号增强;FB_1处理组细胞周期由G_0/G_1期向S期转换时阻滞,细胞线粒体膜电位降低,细胞凋亡相关基因Caspase-3转录升高,Bcl-2转录显著降低(P0.05),Caspase-9和Bax转录极显著升高(P0.01)。结果表明,FB_1对人脐静脉血管内皮细胞有毒性作用,能抑制细胞增殖,使细胞周期阻滞在G0/G1期;能通过线粒体途径诱导HUVEC凋亡。研究结果为深入研究FB_1对人类细胞的毒性作用机制及相关疾病治疗奠定基础。     

龙葵生物碱诱导HeLa细胞凋亡的研究

用MTT法观察龙葵生物碱的体外抗肿瘤作用,用TUNEL染色法检测龙葵生物碱对HeLa细胞凋亡的影响,用免疫细胞化学方法研究龙葵生物碱对HeLa细胞PCNA和突变型P53蛋白表达的影响。浓度为100μg/mL～800μg/mL的龙葵生物碱对HeLa细胞的生长均表现出一定的抑制作用;TUNEL染色结果提示400μg/mL的龙葵生物碱处理HeLa细胞48 h后,能够诱导更多的细胞出现凋亡;免疫细胞化学分析结果显示,400μg/mL的龙葵生物碱处理HeLa细胞48 h后,会使HeLa细胞中PCNA蛋白和突变型P53蛋白表达量显著下调。结果表明,龙葵生物碱在体外具显著抗宫颈癌活性,其作用机制是通过诱导更多的细胞出现凋亡而实现的。     

淫羊藿苷在猪卵泡体外培养过程中对颗粒细胞凋亡的抑制作用

本试验旨在研究淫羊藿苷(ICA)对猪卵泡体外培养过程中颗粒细胞凋亡的影响。设置不同浓度ICA(0、01、1、10μg/mL)添加组,体外培养猪3~5 mm健康有腔卵泡12 h和24 h后,分别收集各组卵泡颗粒细胞,流式细胞仪检测细胞凋亡率,RT-PCR检测凋亡相关基因Caspase-3、Bcl-2和Bax mRNA相对表达水平。结果表明,猪卵泡体外培养12 h和24 h,添加1μg/mL ICA组颗粒细胞凋亡率较对照组显著降低(P005),1μg/mL组的Caspase-3、Bax mRNA表达量最低,Bcl-2 mRNA表达量最高,且显著高于对照组(P005)。研究结果提示,ICA在卵泡闭锁过程中可明显抑制颗粒细胞凋亡,这一作用可能主要是通过抑制线粒体凋亡途径而实现的。     

牛支原体P48蛋白诱导EBL细胞增殖和凋亡的研究

试验旨在研究牛支原体P48蛋白对胎牛肺（embryonic bovine lung,EBL）细胞增殖和凋亡的影响。收集不同时间段、不同浓度P48蛋白与EBL细胞共孵育的样品,通过MTT法检测细胞增殖率;DAPI染核法观察EBL细胞核形态变化;流式细胞技术检测该蛋白诱导EBL细胞的凋亡率;实时荧光定量PCR检测凋亡标志物的mRNA相对表达变化;Western blotting方法检测Bax和Beclin-1蛋白表达水平。结果显示：当作用时间为72 h,P48蛋白浓度在10 μg/mL时,对EBL细胞增殖有极显著的抑制作用（P<0.01）,在0.1和0.5 μg/mL时对EBL细胞的增殖的抑制作用不显著（P>0.05）;经蛋白诱导12 h细胞核形态未有明显变化,24 h细胞核形态发生皱缩和凝聚,48和72 h细胞核发生碎裂;凋亡标志基因mRNA表达在2和12 h没有明显提高,在24、48、72 h有显著提高,与作用时间呈正相关,同时凋亡相关蛋白Bax和Beclin-1的表达随之显著提高。流式细胞技术结果显示P48蛋白诱导EBL细胞凋亡率为48.44%。综上表明,牛支原体P48重组蛋白能够抑制EBL细胞的增殖,促进细胞凋亡,为进一步揭示牛支原体的致病机制提供参考依据。     

MPTP在庆大霉素诱导MDCK细胞线粒体凋亡途径中的作用

为研究线粒体膜通透性转换孔(mitochondrial permeablity transition pore,MPTP)在庆大霉素(gentamicin,GM)诱导MDCK细胞线粒体凋亡中的作用,试验用4 mmol/L GM和2μmol/L抑制剂CsA(cyclosporin A,CsA)单独或联合处理MDCK细胞24 h,流式细胞术检测MPTP开放情况和细胞凋亡率;JC-1探针检测线粒体膜电位的变化;荧光检测线粒体变化;免疫印迹法检测Bax与Bcl-2表达量,Caspase-9、Caspase-3和PARP蛋白活化情况,Cyt C和AIF释放。结果显示,CsA能够显著或极显著抑制GM引起的MDCK细胞MPTP的开放,细胞凋亡率的上升,线粒体膜电位下降,Bcl-2/Bax比值下降,Caspase-9、Caspase-3和PARP蛋白的活化以及Cyt C与AIF的释放(P0.05或P0.01);说明MPTP正向调节GM引起的MDCK线粒体凋亡。     

线粒体凋亡途径在玉米赤霉烯酮致大鼠睾丸支持细胞凋亡中的作用

为探讨玉米赤霉烯酮(zearalenon,ZEA)雄性生殖毒性作用机理,研究ZEA诱导大鼠睾丸支持细胞(sertoli cell,SC)的凋亡途径,试验选取大鼠原代SC为研究材料,用不同浓度ZEA(0、5、10、20μmol/L)处理SC 24 h后,采用实时荧光定量PCR法检测Bax和Bcl-2 mRNA表达水平;用Western blotting法检测Bax、Bcl-2等线粒体凋亡途径相关蛋白表达;同时检测了20μmol/L ZEA联合Caspase-8抑制剂(Z-IETD-FMK)处理对SC凋亡率和线粒体凋亡相关蛋白的影响。结果显示,与对照组相比,20μmol/L ZEA组细胞Bcl-2转录水平显著下降(P<0.05),Bax转录水平显著上升(P<0.05);10、20μmol/L ZEA组Bax/Bcl-2比值及Cyto-CytC、Cleaved Caspase-9、Cleaved Caspase-3表达量极显著上升(P<0.01),而Mito-CytC表达量极显著下降(P<0.01);与ZEA组相比,ZEA与Z-IETD-FMK联合处理可使ZEA诱导的SC凋亡率极显著下降(P<0.01),tBid/Bid、Bax/Bcl-2、Cyto-CytC、Cleaved-Caspase3、Cleaved-Caspase9蛋白表达显著或极显著下降(P<0.05;P<0.01),而Mito-CytC表达量极显著上升(P<0.01)。综合试验结果,ZEA能够通过线粒体途径诱导大鼠SC发生凋亡。     

线粒体凋亡途径在玉米赤霉烯酮致大鼠睾丸支持细胞凋亡中的作用

为探讨玉米赤霉烯酮(zearalenon,ZEA)雄性生殖毒性作用机理,研究ZEA诱导大鼠睾丸支持细胞(sertoli cell,SC)的凋亡途径,试验选取大鼠原代SC为研究材料,用不同浓度ZEA(0、5、10、20μmol/L)处理SC 24 h后,采用实时荧光定量PCR法检测Bax和Bcl-2 mRNA表达水平;用Western blotting法检测Bax、Bcl-2等线粒体凋亡途径相关蛋白表达;同时检测了20μmol/L ZEA联合Caspase-8抑制剂(Z-IETD-FMK)处理对SC凋亡率和线粒体凋亡相关蛋白的影响。结果显示,与对照组相比,20μmol/L ZEA组细胞Bcl-2转录水平显著下降(P0.05),Bax转录水平显著上升(P0.05);10、20μmol/L ZEA组Bax/Bcl-2比值及Cyto-CytC、Cleaved Caspase-9、Cleaved Caspase-3表达量极显著上升(P0.01),而Mito-CytC表达量极显著下降(P0.01);与ZEA组相比,ZEA与Z-IETD-FMK联合处理可使ZEA诱导的SC凋亡率极显著下降(P0.01),tBid/Bid、Bax/Bcl-2、Cyto-CytC、Cleaved-Caspase3、Cleaved-Caspase9蛋白表达显著或极显著下降(P0.05;P0.01),而Mito-CytC表达量极显著上升(P0.01)。综合试验结果,ZEA能够通过线粒体途径诱导大鼠SC发生凋亡。     

呕吐毒素对IPEC-J2细胞凋亡的影响

本研究以IPEC-J2细胞为材料,研究不同浓度和时间处理下呕吐毒素(DON)对猪空肠上皮细胞凋亡的影响。通过CCK-8试剂盒检测细胞增殖毒性,筛选出合适的DON作用时间(6、12、24 h)。通过低浓度(200 ng/mL)和高浓度(2 000 ng/mL)DON分别作用IPEC-J2细胞6、12、24 h,检测DON对细胞有丝分裂周期和细胞早期凋亡的影响。结果表明:1)DON对IPEC-J2细胞生长有明显抑制作用,200和2 000 ng/mL DON浓度下,48和72 h的细胞存活率显著低于24 h(P0.05);2 000 ng/mL DON浓度下,72 h的细胞存活率显著低于48 h(P0.05)。2)不同DON浓度对细胞周期影响不同,低浓度DON主要作用于细胞有丝分裂S期,干扰DNA的复制;而高浓度DON主要作用于细胞有丝分裂G2/M期,干扰有关酶与纺锤丝蛋白质的合成。3)DON作用6 h,低浓度DON组和高浓度DON组早期凋亡率和总凋亡率显著高于对照组(P0.05);DON作用12 h,高浓度DON组早期凋亡率和总凋亡率显著高于对照组和低浓度DON组(P0.05)。由此可见,DON抑制了IPEC-J2细胞增殖,低浓度DON使细胞有丝分裂停留在S期,高浓度DON使细胞有丝分裂停留在G2/M期。DON促使细胞早期凋亡,使总凋亡率上升,且促凋亡作用随DON浓度升高而增强。     

线粒体凋亡通路在皮质酮(CORT)诱导海马神经元凋亡中的作用

为在细胞水平探讨皮质酮(CORT)诱导HT22细胞凋亡的机制,以模拟冷应激过程中机体分泌的糖皮质激素对海马神经元的作用。试验组HT22细胞用500μmol/L CORT处理3 h,对照组不予处理。用CCK8法检测CORT对HT22细胞活力的影响,Annexin/PI流式细胞术检测细胞凋亡率。为了进一步研究CORT引起的海马神经元凋亡是否是由线粒体凋亡通路介导的,用JC-1探针检测线粒体膜电位的变化,免疫蛋白印迹(Western blot)检测凋亡相关蛋白细胞色素c(Cyt-c)、Bcl-2、Bax、Caspase-3的表达。结果显示,与对照组相比,500μmol/L CORT处理组细胞生存率显著降低,细胞凋亡率显著升高,线粒体膜电位显著下降,Cyt-c、Bax/Bcl-2及活化的Caspase-3表达水平显著升高。结果表明,500μmol/L CORT处理3 h会导致HT22细胞凋亡,并且线粒体凋亡通路在该过程中发挥重要作用。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Changes in proportion of canine urinary calculi composed of calcium oxalate or struvite in specimens analyzed from 1981 through 2001

The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.     

Smart Phone Assisted City-scale Wireless Sensor Network Deployment for Transportation System Monitoring

<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.