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Subacute toxicological study of PG102, a water-soluble extract derived from Actinidia arguta, in SD rats
2008
Hong, E.S. (Helixir Co., Seoul, Republic of Korea) | Kim, M.J. (Helixir Co., Seoul, Republic of Korea) | Kwon, E.J. (Helixir Co., Seoul, Republic of Korea) | Kim, L.H. (Seoul National University, Seoul, Republic of Korea) | Kim, D.H. (Seoul National University, Seoul, Republic of Korea) | Eo, H.K. (Helixir Co., Seoul, Republic of Korea) | Park, E.J. (Helixir Co., Seoul, Republic of Korea) | Kim, S.Y. (Seoul National University, Seoul, Republic of Korea) | Kim, S.H. (Helixir Co., Seoul, Republic of Korea), E-mail: seonhee@helixir.co.kr
It was previously found that PG102, a water-soluble extract derived from Actinidia arguta, was able to modulate Th1/Th2 pathways and suppress IgE production resulting in dramatic amelioration of atopic dermatitis in NC/Nga mouse and hairless rat models. In order to evaluate the subacute toxicity of PG102, female and male SD rats were daily fed with various doses of PG102 for 4 weeks. Six week old SD rats were randomly divided into 4 groups and orally administrated with 100-, 300-, and 1,000-mg/kg of PG102 as well as the vehicle only. At the end of the study, no significant differences in the body and organ weights were observed between control and treated rats of both genders. Hematological and blood chemical analysis showed little differences between the animal groups. Neither gross abnormalities nor histopathological changes were found. PG102 produced little or no subacute toxicity and could be used as a safe nutraceutical for the treatment of individuals with allergic diseases including atopic dermatitis.
Mostrar más [+] Menos [-]Comparative serological analysis of outer membrane proteins extracted from Brucella abortus Korean isolates and 1119-3 strains
2008
Cha, S.B. (Seoul National University, Seoul, Republic of Korea) | Kang, M.L. (Seoul National University, Seoul, Republic of Korea) | Lee, W.J. (Seoul National University, Seoul, Republic of Korea) | Shin, M.K. (Seoul National University, Seoul, Republic of Korea) | Cho, D.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Jung, S.C. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea) | Yoo, H.S. (Seoul National University, Seoul, Republic of Korea), E-mail: yoohs@snu.ac.kr
Brucellosis is one of the most important zoonosis in worldwide. As one of the control measures, attempts have been made to develop new diagnostic methods using filed isolates as a national policy in many countries. Currently, bovine brucellosis in Korea have been received attention in both public health and economical aspects due to sudden increase of outbreak. Based on the situation, we compared standard strain (B. abortus 1119-3) with field isolates to reveal the differences among them. Biological and biochemical charateristics, antibiotic resistance profiles, outer membrane proteins (OMPs) and lipopolysaccharide analysis of the strains were included in this study. For the diagnostic purpose, an attempt was made to find out a novel antigen from the Korean isolates by serological analysis. There were differences about 55 kDa, 36-38 kDa and 20 kDa in analysis of OMPs by SDS-PAGE and Western blot with positive sera (greater-than or equal to 1:400 in SAT titer). Also, a serological diagnostic method, ELISA was conducted using OMPs of the strains as novel antigen. Relationships between O.D. and SAT titer were analyzed using field sera showing different SAT titer. High correlation coefficient was observed between SAT titer and ELISA. Results from this study suggested that a new diagnsotic method should be developed using their own field isolates in each country.
Mostrar más [+] Menos [-]Inhibitory effects of herbal extracts (Meliae ezadarach, Dryopteris crassirhizoma, Quisqualis indica var villosa) on Larval migration of Anisakis spp. in vitro
2008
Kwon, H.N. (Chungbuk National University, Cheongju, Republic of Korea) | Jee, C.H. (Chungbuk National University, Cheongju, Republic of Korea), E-mail: chjee@cbnu.ac.kr
A high incidence of Anisakiasis has been reported in many countries where people eat frequently raw or undercooked seafood. Anisakis spp. larvae were obtained from the mackerel acquired from a fish market of Cheongju city. They were divided into several groups and placed in culture dishes containing RPMI-1640 (culture media), in the presence or absence of different concentrations of herbal extracts (Meliae ezadarach, Dryopteris crassirhizoma, Quisqualis indica var villosa). The objective of the present study was to investigate the activity of larval migration inhibition in vitro. Meliae ezadarach at the concentrations of 7.5, 15, and 30 mg/ml effectively inhibited the larvae migration in time-dependent manner during experimental period of 0-24 h. Treatment of Meliae ezadarach at the three concentrations completely inhibited the larvae migration in vitro. Dryopteris crassirhizoma at the concentrations of 5, 10, and 20 mg/ml also effectively inhibited the larvae migration in a time-dependent manner. The treatment of Dryopteris crassirhizoma for 12 h completely inhibited the larvae migration. The inhibitory effect of Dryopteris crassirhizoma was stronger than that of Meliae ezadarach. Although Quisqualis indica var villosa also showed the inhibitory effect on larvae migration, its inhibitory efficacy was the weakest among tested herbal extracts. These results indicated that some herbal extracts may be useful in controlling human anisakiasis.
Mostrar más [+] Menos [-]Use of epidemiologic risk modeling to evaluate control of foot-and-mouth disease in southern Thailand
2008
Wongsathapornchai, K. | Salmān, Muḥammad | Edwards, J.R. | Morley, P.S. | Keefe, T.J. | Van Campen, H. | Weber, S. | Premashthira, S.
Objective--To assess the impacts of the introduction of foot-and-mouth disease (FMD) and various FMD control programs in southern Thailand. Animals--A native population of 562,910 cattle and 33,088 buffalo as well as 89,294 animals legally transported into southern Thailand. Procedures--A quantitative risk assessment was used to ascertain the probability of FMD introduction, and an intrinsic dynamic model was used to assess impacts. Value for the transmission rate (β) was estimated. Five scenarios created to assess the impacts of nonstructural protein (NSP) testing, mass vaccination, and culling were examined. Impacts were assessed through an examination of the estimated annual cumulative incidence (ACI) of FMD. The ACIs of various scenarios were compared by use of the Tukey Studentized range technique. Results--β was estimated at 0.115. Approximately 35,000 cases of FMD would be expected from the baseline situation. A 30% reduction of ACI was detected with the introduction of NSP antibody testing. Prophylactic vaccination resulted in an 85% reduction of ACI. Concurrent use of NSP antibody testing and vaccination reduced the ACI by 96%, and the addition of an eradication policy resulted in a slightly greater decrease in the ACI (98%). Conclusions and Clinical Relevance--The study used epidemiologic models to investigate FMD control interventions. Results suggested that vaccination has more impact than the use of NSP testing. Use of the NSP test reduced ACI during peak seasons, whereas vaccination diminished the underlying incidence. The best mitigation plan was an integrated and strategic use of multiple control techniques.
Mostrar más [+] Menos [-]Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004)
2008
P. G. Howell | Jane P. Nurton | Daleen Nel | Carina W. Lourens | A. J. Guthrie
Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and localized in fections affecting only individual horses. This study of the seasonal prevalence of equine encephalosis virus has a corollary and serves as a useful model in the seasonal incidence of the serotypes of African horse sickness and bluetongue in regions where the respective diseases are endemic.
Mostrar más [+] Menos [-]Preliminary survey of ticks (Acari: Ixodidae) on cattle in Central Equatoria State, Southern Sudan
2008
D.A. Salih | I.I. Julla | S.M. Hassan | A.M. El Hussein | F. Jongejan
In a preliminary survey conducted in 2005, the species composition and seasonality of ticks infesting cattle in Central Equatoria State, Southern Sudan was determined. Three locations were selected (Gumbo, Khor Rumla and Nyaing) and surveyed every 3 months. Two cattle herds in each of the three locations were visited four times during the study period. Total body collections of ticks were made from each of five cattle (Nilotic Zebu breed) kept in six different herds. Four tick genera and ten species were identified. The tick species identified were Amblyomma lepidum, Amblyomma variegatum, Boophilus annulatus, Boophilus decoloratus, Hyalomma marginatum rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus praetextatus and Rhipicephalus sanguineus group. The highest number of ticks was collected in October during the rainy season. A finding of great significance was that R. appendiculatus, vector of East Coast fever, has now firmly established itself throughout the year with possible implications for cattle production in Central Equatoria State.
Mostrar más [+] Menos [-]Molecular characterization of SAT-2 foot-and-mouth disease virus isolates obtained from cattle during a four-month period in 2001 in Limpopo Province, South Africa
2008
B.S. Phologane | R.M. Dwarka | D.T. Haydon | L.J. Gerber | W. Vosloo
Foot-and-mouth disease (FMD) is an acute, highly contagious viral infection of domestic and wild cloven-hoofed animals. The virus is a single-stranded RNA virus that has a high rate of nucleotide mutation and amino acid substitution. In southern Africa the South African Territories (SAT) 1-3 serotypes of FMD virus are maintained by large numbers of African buffaloes (Syncerus caffer), which provide a potential source of infection for domestic livestock and wild animals. During February 2001, an outbreak of SAT-2 was recorded in cattle in the FMD control zone of South Africa, adjacent to the Kruger National Park (KNP). They had not been vaccinated against the disease since they form the buffer between the vaccination and free zones but in the face of the outbreak, they were vaccinated as part of the control measures to contain the disease. The virus was, however, isolated from some of them on several occasions up to May 2001. These isolates were characterized to determine the rate of genetic change in the main antigenic determinant, the 1D/2A gene. Nucleotide substitutions at 12 different sites were identified of which five led to amino acid changes. Three of these occurred in known antigenic sites, viz. the GH-loop and C-terminal part of the protein, and two of these have previously been shown to be subject to positive selection. Likelihood models indicated that the ratio of non-synonymous to synonymous changes among the outbreak sequences recovered from cattle was four times higher than among comparable sequences isolated from wildlife, suggesting that the virus may be under greater selective pressure during rapid transmission events.
Mostrar más [+] Menos [-]Prevalence of the dog nematode <i>Spirocerca lupi</i> in populations of its intermediate dung beetle host in the Tshwane (Pretoria) Metropole, South Africa
2008
C.A. Du Toit | C.H. Scholtz | W.B. Hyman
Spirocerca lupi (Spirurida: Spirocercidae) is a cosmopolitan parasite, principally of domestic dogs and dung beetles are its main intermediate hosts. In South Africa there has recently been growing concern over the upsurge of reported cases of clinical spirocercosis in dogs, while little is known or understood about the dynamics of the host-parasite associations between dung beetles and this nematode. We determined and compared the prevalence of infection in dung beetles between rural, urban and periurban areas of Tshwane (Pretoria) Metropole. Dung beetles were sampled during April and October 2006, at various localities in each of these areas. Localities were selected on the basis of being focal areas of high infection with S. lupi in dogs. Pig, dog and cow dung-baited pitfall traps were used for sampling the beetles. Trap contents were collected 48 h after the traps had been set and only dung beetles were collected from the traps. In total, 453 specimens belonging to 18 species were collected from 63 pitfall traps in all three areas. The numbers of species that were collected varied among the three areas. Dung beetles, irrespective of species (18) and numbers (447), predominantly preferred pig dung. The prevalence of dung beetles infected with the larvae of S. lupi varied considerably in the three areas. In the urban area 13.5 % of the dung beetles dissected were infected, while the prevalence of S. lupi in dung beetles in the rural area was 2.3 %. All the dung beetles that were infected with this nematode showed a preference for omnivore (pig and dog) dung.
Mostrar más [+] Menos [-]Field experiences with early pregnancy diagnosis by progesterone-based ELISA in sows
2008
M.H. Boma | G. Bilkei
In four Kenyan pig breeding units the pregnancy diagnosis of sows has been carried out in two groups: Group 1 (n = 1911): the sows were transrectaly pregnancy tested between Days 1722 post-mating by ultrasound. Sows testing non-pregnant immediately received one dose of 400 IU pregnant mare serum gonadotropin (PMSG) (equine chorion gonadotropin, eCG) and 200 IU human chorion gonadotropin (hCG). On showing signs of oestrous, the animals were subsequently artificially inseminated (AI). Group 2 (n = 1923): sows were pregnancy tested by serum progesterone (P4)-based enzyme-linked immunosorbent assay (ELISA) on Day 17 post-breeding. P4 concentrations were categorized as positive (> 5 ng/ml) or negative (< 5 ng/ml). Sows testing non-pregnant immediately received one dose of 400 IU PMSG and 200 IU hCG by injection, and were subsequently artificially inseminated. The following parameters were evaluated: sows diagnosed non-pregnant, days from first post-weaning insemination until the sows were inseminated at their first return to oestrus; farrowing rate and total piglets born and number of live-born piglets in litters. The percentage of sows diagnosed non-pregnant in the two groups, as well as the totals of born piglets and of live-born piglets in litters did not differ significantly between the two groups. The number of days from the first post-weaning mating until the sows were artificially inseminated at their first return to oestrus and the administration of eCG and hCG was shorter (P < 0.01) and farrowing rate was higher (P < 0.01) in the ELISA-tested sows.
Mostrar más [+] Menos [-]Production trials involving use of the FAMACHA© system for haemonchosis in sheep : preliminary results
2008
J.A. Van Wyk
In three trials conducted on two separate farms the production of sheep treated for naturally acquired haemonchosis using the FAMACHA© system of targeted selective treatment (TST) (i.e. to treat only those animals unable to manage unaided in the face of heavy Haemonchus challenge) was compared to that of suppressively drenched sheep in the same flock. As expected by the research team who developed and evaluated the FAMACHA© system, TST did result in some loss in production. However, despite high levels of worm challenge in two of the trials and the fact that the comparison was with suppressive drenching which is not sustainable, the total effect was relatively small in relation to the important advantage of using the TST as regards reduced selection for anthelmintic resistance (AR). Concerning the sustainability of worm control, it is concluded that the development of drug resistance to anthelmintics leaves sheep and goat farmers in South Africa no choice but to use methods of TST such as FAMACHA©. The FAMACHA© system can also be a useful clinical aid for early on-farm detection of AR by farmers; the degree of improvement in the colour of the ocular mucous membrane from pale to red in individually drenched anaemic animals over a period of 7-14 days can give a good indication of the efficacy of the compound(s) used.
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