丙硫咪唑治疗幼驹杆虫病的效果

丙硫咪唑(Albendazole)又称抗蠕敏,是近年来使用的一种新型驱虫药,具有广谱、高效、低毒、低残留等特点。据文献报道在马里、塞内加尔、中非等国家和地区用于治疗人的类园线虫病、钩虫病均取得良好疗效.国内用于治疗家畜各种蠕虫病也取得较满意效果,现将我们用丙硫咪唑治疗幼驹杆虫病实验结果报告如下:

秋冬季节猪场疾病多发的原因及对策

进入秋冬季节,由于气候变化,给猪场的正常生产带来了很多不稳定因素,随着冷空气的到来,猪群的应激反应明显增加;加之夏季高温对猪群的余威,猪群的体质还处在一个恢复期,如何保持秋冬季节猪群的健康稳定,提升猪场的抗风险能力非常重要。本文主要针对猪场秋冬季节多发疾病、诱发原因及防控措施进行综述。

The Parasitoid Factor in the Virulence and Spread of Lepidopteran Baculoviruses

Insect parasitoids and baculoviruses play important roles in the natural and strategic biological control of insects. The two parasites are frequent competitors within common hosts and much research has focused on the negative impact that baculoviral host infections have on parasitoids. This review summarizes the impacts that parasitoids may have on the virulence and spread of lepidopteran baculoviruses. By changing host behavior and development, parasitoids have been shown to decrease baculovirus virulence and productivity within parasitized baculovirus-susceptible hosts; however, studies of the tools used by hymenopteran parasitoids to overcome their hosts'immune systems, suggest that parasitoids may, in some cases, facilitate baculoviral infections in less susceptible hosts. Laboratory and field research have demonstrated that parasitoids can mechanically transmit baculoviruses between insects, and in this way, increase the efficacy of the viruses. Instances of new, more virulent isolates of baculoviruses have been recorded from specifically parasitoid-targeted hosts suggesting other possible benefits from the transmission or activation of baculoviruses by parasitoids.

Baculovirus per os Infectivity Factors Are Involved in HearNPV ODVs Infection of HzAM1 Cells in vitro

Baculoviruses produce two viral phenotypes, the budded virus （BV） and the occlusion-derived virus （ODV）. ODVs are released from occlusion bodies in the midgut where they initiate a primary infection. Due to the lack of an in vitro system, the molecular mechanism of ODV infection is still unclear. Here we present data demonstrating that Helicoverpa armigera nucleopolyhedrovirus （HearNPV） ODV infected cultured Hz-AM1 cells in a pH dependent manner. The optimal pH for ODV infection was 8.5, which is same to that in the microvilli of midgut epithelial cells, the ODV native infection sites. Antibodies neutralization analysis indicated that four HearNPV oral infection essential genes p74, pif-l, pif-2 and pif-3 are also essential for HearNPV ODV infection in vitro. Thus, HearNPV-HzAM1 system can be used to analyze the mechanism of ODV entry.

Association of Helicobacter pylori infection and giardiasis: Results from a study of surrogate markers for fecal exposure among children

AIM: To investigate whether Helicobacter pylori (H pylori) infection is associated with hepatitis A virus (HAV) infection, presence of enteroparasites, and other surrogates of fecal exposure. METHODS: We conducted a cross-sectional study in 121 children consecutively admitted at a pediatric hospital in Salvador, Brazil. H pyloriand HAV infection were identified by the presence of serum antibodies. Stool specimens were examined for the presence of ova and parasites. A structured questionnaire inquiring about sanitary conditions and life style was applied to each subject. RESULTS: Fifty-one of the 121 children (42.1%) were found to be seropositive for H pylori, and 45 (37.2%) for HAV. The seroprevalence of Hpyloriand HAV both increased significantly with age. Cross-tabulation of data showed that 26 (21.5%) were seropositive and 51 (42.1%) were negative for both H py/lriand HAV antibodies (x^2=7.18, OR=2.8, CI 1.30-5.97). The age adjusted OR for an HAV-infected child being H pylori positive was 2.3 (CI 1.02-5.03). The agreement between H pylori and HAV seropositivity was fair (k=0.24). After controlling for possible confounding, the variables remaining independently associated with seropositivity to H pylori were age, presence of Giardia lamblia in feces (OR=3.2, 95%CI, 1.1-9.5) and poor garbage disposal quality (OR=2.4, 95%CI, 1.1-5.1). CONCLUSION: Our data suggest that H pylori infection is associated with surrogate markers of fecal exposure. Thus, we conclude that the fecal-oral route is relevant in the transmission of HP among children in an urban setting of a developing country. The association observed between G. lamblia and H pylori infection may have several explanations. Further studies to investigate this relationship are warranted.

Susceptibility to AcMNPV and Expression of Recombinant Proteins by a Novel Cell Clone Derived from a Trichoplusia ni QAU-BTI-Tn9-4s Cell Line

It is well known that Tn5B1-4 (commercially known as the High Five) cell line is highly susceptible to baculovirus and provides superior production of recombinant proteins when compared to other insect cell lines.But the characteristics of the cell line do not always remain stable and may change upon continuous passage.Recently an alphanodavirus,named Tn5 Cell Line Virus (or TNCL Virus),was identified in High Five cells in particular.Therefore,we established a new cell line,QB-Tn9-4s,from Trichoplusia ni,which was determined to be free of TNCL virus by RT-PCR analysis.In this paper,we describe the development of a novel cell clone,QB-CL-B,from a low passage QB-Tn9-4s cell line and report its susceptibility to AcMNPV,and the level of recombinant protein production.This cell clone was similar to its parental cells QB-Tn9-4s and Tn5B1-4 cells in morphology and growth rate;although it also showed approximately the same responses to AcMNPV infection and production of occlusion bodies,there were higher levels of recombinant protein production in comparison to QB-Tn9-4s (parental cells) and High5 cells.

A New Strain of Entomopathogenic Bacillus of the Tea Pest, Eterusia magnifica （Butl.） （Zyganiidae： Lepidoptera） from Darjeeling Foothill Region of India

An entomopathogenic strain of Bacillus sp. was isolated from diseased red slug caterpillars of the leaf-feediug pest of tea, Eterusia magnifica, from the Darjeeling foothill region. Analysis of the bacterimn based on polyphasic approach such as growth phase, biochemical tests, whole body＂ protein, crystal protein profiles along with bioassay （i.e. LC50 and LT50 values） established it as a different strain but close to Bacillus thuringiensis kurstaki （Btk）, the commercial microbial pesticides of lepidopterans. Among biochemical parameters differences were noted between the new strain and Btk in ONPG, lysine decarboxylase, omithin decarboxylase, urease, nitrate reduction, V-P and glucose utilization tests. PAGE analysis of the whole body protein for the new strain recorded a 34 kDa band which was absent in Btk （used as reference）. Crystal protein profile of the newly isolated bacterial strain showed 53 and 49 kDa bands whereas in Btk only 52 kDa band was evident. Although the LC50 values of the new strain and Btk were close, their LT50 values were much different, the new strain showing a lower value than Btk. In light of the above differences and in absence of any report of entomopathogenic bacterial strain of E. magnifica, the isolated strain of Bacillus appeared to be new to science and hence was designated as RS01. The new strain opens up the possibility of its futttre use as microbial pesticide after standardizing its formulation and checking its safety aspects.

Production of CCHF Virus-Like Particle by a Baculovirus-Insect Cell Expression System

Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is a tick-born virus of the Nairovirus genus within the Bunyaviridae family,which is widespread and causes high fatality.The nucleocapsid of CCHFV is comprised of N proteins that are encoded by the S segment.In this research,the N protein of CCHFV was expressed in insect cells using a recombinant baculovirus.Under an electron microscope,Virus-Like Particles (VLPs) with various size and morphology were observed in cytoplasmic vesicles in the infected cells.Sucrose-gradient purification of the cell lysate indicated that the VLPs were mainly located in the upper fraction after ultracentrifugation,which was confirmed by Western blot analysis and immuno-electron microscopy (IEM).

Expression of Rice Gall Dwarf Virus Outer Coat Protein Gene (S8) in Insect Cells

To obtain the P8 protein of Rice gall dwarf virus (RGDV) with biological activity,its outer coat protein gene S8 was expressed in Spodoptera frugiperda (Sf9) insect cells using the baculovirus expression system.The S8 gene was subcloned into the pFastBacTM1 vector,to produce the recombinant baculovirus transfer vector pFB-S8.After transformation,pFB-S8 was introduced into the competent cells (E.coli DH10Bac) containing a shuttle vector,Bacmid,generating the recombinant bacmid rbpFB-S8.After being infected by recombinant baculovirus rvpFB-S8 at different multiplicities of infection,Sf9 cells were collected at different times and analyzed by SDS-PAGE,Western blotting and immunofluorescence microscopy.The expression level of the P8 protein was highest between 48-72 h after transfection of Sf9 cells.Immunofluorescence microscopy showed that P8 protein of RGDV formed punctate structures in the cytoplasm of Sf9 cells.

AcMNPV As A Model for Baculovirus DNA Replication

Baculoviruses were first identified as insect-specific pathogens, and it was this specificity that lead to their use as safe, target specific biological pesticides. For the past 30 years, AcMNPV has served as the subject of intense basic molecular research into the baculovirus infectious cycle including the interaction of the virus with a continuous insect cell line derived from Spodoptera frugiperda. The studies on baculoviruese have led to an in-depth understanding of the physical organization of the viral genomes including many complete genomic sequences, the time course of gene expression, and the application of this basic research to the use of baculoviruses not only as insecticides, but also as a universal eukaryotic protein expression system, and a potential vector in gene therapy. A great deal has also been discovered about the viral genes required for the replication of the baculovirus genome, while much remains to be learned about the mechanism of viral DNA replication. This report outlines the current knowledge of the factors involved in baculovirus DNA replication, using data on AcMNPV as a model for most members of the Baculoviridae.

Clinico-pathological Studies in Experimental Eimeria Infection in Domestic Rabbits （Oryctolagus Cuniculus）

Clinico-pathological study of experimental Eimeria species infection （coccidiosis） such as E. magna, E. intestinalis, E. irresidua, E. media and E. perforans in rabbits was conducted with dose inocula of 1 lac sporulated oocysts. These rabbits were divided into two groups each consisting of 12 rabbits. Two rabbits of infected untreated group died of severe disease on the 27^th ＆ 28^th day post infection. The intestine of dead animals showed elevated lesions in the middle half portion with congestion and destruction of villar epithelium.

Genetic Engineering of Tobacco with Double Resistance to Both Virus and Insect

Expression vector pE14 with double resistance to virus and insect was constructed by inserting CW-cp gene and Bt-toxin gene one by into T-DNA of the same binary vector pE3. Tobacco was then transformed with Agrbacterium tumefaciens (At)GV311-SE carrying PE14. Nopaline assay and PCR amplification confirmed that both CW-cp gene and Bt-toxin gene had been introduced into tobacco genome by T-DNA of PE3. Test attack with virus and demonstrated, in some of the transgenic plants, double resistance to both infection by CMV and damage by Manduca sexta.

Characterization of the viral fibroblast growth factor homolog of Helicoverpa armigera single nucleopolyhedrovirus

Fibroblast growth factor(FGF) is found throughout multicellular organisms; however, fgf homologs(vfgf) have only been identified among viruses in lepidopteran baculoviruses. The function of v FGFs from Group I alphabaculoviruses, including Autographa californica multiple nucleopolyhedrovirus(Ac MNPV) and Bombyx mori nucleopolyhedrovirus(Bm NPV), involves accelerated killing of infected larvae by both viruses. The v FGF of Group II alphabaculovirus is structurally different from that of Group I alphabaculovirus, with a larger C-terminal region and additional N-linked glycosylation sites. In this study, we characterized the Group II alphabaculovirus v FGF of Helicoverpa armigera single nucleopolyhedrovirus(Hear NPV). The transcription and expression of vfgf was detected at 3 h and 16 h post-infection in Hear NPV-infected cells. To further study v FGF function, we constructed vfgf-knockout and-repaired Hear NPV bacmids and investigated their affect in both cultured cells and insects. Deletion of vfgf had no effect on budded-virus production or viral DNA replication in cultured Hz AM1 cells. However, bioassays showed that Hear NPV vfgf deletion significantly increased the median lethal dose and delayed the median lethal time by ~12 h in the host insect when the virus was delivered orally. These results suggested that v FGF is an important virulent factor for HearN PV infection and propagation in vivo.