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Ticks (Acari: Ixodidae) collected from animals in three western, semi-arid nature reserves in South Africa : research communication Full text
2007
H. Golezardy | I.G. Horak
The objective of this study was to make an inventory of the ixodid tick species infesting wild animals in three western, semi-arid nature reserves in South Africa. To this end 22 animals in the Kgalagadi Transfrontier Park, 10 in the West Coast National Park and 16 in the Karoo National Park were examined. Fourteen tick species were recovered, of which Hyalomma truncatum, Rhipicephalus exoph thalmos and Rhipicephalus glabroscutatum were each present in two reserves and the remainder only in one. The distributions of two of the 14 tick species recovered, namely Rhipicephalus capensis and Rhipicephalus neumanni, are virtually confined to the western semi-arid regions of southern Africa. Hyalomma truncatum, R. capensis and R. glabroscutatum were the most numerous of the ticks recovered, and eland, Taurotragus oryx, were the most heavily infested with the former two species and gemsbok, Oryx gazella, and mountain reedbuck, Redunca fulvorufula, with R. glabroscutatum.
Show more [+] Less [-]Antimicrobial activity of bovine bactericidal permeability-increasing protein-derived peptides against gram-negative bacteria isolated from the milk of cows with clinical mastitis Full text
2007
Chockalingam, A. | Zarlenga, D.S. | Bannerman, D.D.
Objective--To evaluate antimicrobial activity of bovine bactericidal permeability-increasing protein (bBPI)-derived synthetic peptides against mastitis-causing gram-negative bacteria. Sample Population--Bacterial isolates from the milk of cows with clinical mastitis. Procedures--3 peptides were synthesized with sequences corresponding to amino acids 65 to 99 (bBPI6599) or 142 to 169 (bBPI142169) or the combination of amino acids 90 to 99 and 148 to 161 (bBPI9099,148161) of bBPI. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of these peptides against bacterial isolates from cows with mastitis were determined by use of a standardized broth microdilution assay. The ability of these peptides to retain their antimicrobial activity in serum and milk was also evaluated. Finally, bacterial lipopolysaccharide (LPS)-neutralizing activity of these peptides was assayed with the Limulus amebocyte lysate test. Results--Of the 3 peptides tested, bBPI9099,148161 had the widest spectrum of antimicrobial activity, with MIC and MBC values ranging from 16 to 64 Mg/mL against Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp and from 64 to 128 Mg/mL against Pseudomonas aeruginosa. None of the peptides had any growth-inhibitory effect on Serratia marcescens. The antimicrobial activity of bBPI9099,148161 was inhibited in milk, but preserved in serum. Finally, bBPI142169 and bBPI9099,148161 completely neutralized LPS. Conclusions and Clinical Relevance--bBPI9099,148161 is a potent neutralizer of the highly proinflammatory molecule bacterial LPS and has antimicrobial activity against a variety of gram-negative bacteria. The ability of bBPI9099,148161 to retain antimicrobial activity in serum suggests a potential therapeutic application for this peptide in the management of gram-negative septicemia.
Show more [+] Less [-]A comparative epidemiological study of hantavirus infection in Japan and Far East Russia
2007
Kariwa, H.(Hokkaido Univ., Sapporo (Japan)) | Lokugamage, K. | Lokugamage, N. | Miyamoto, H. | Yoshii, K. | Nakauchi, M. | Yoshimatsu, K. | Arikawa, J. | Ivanov, L.I. | Iwasaki, T. | Takashima, I.
Hantaviruses are causative agents of some severe human illnesses, including hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). The viruses are maintained by rodent hosts, and humans acquire infection by inhaling virus-contaminated excreta from infected animals. To examine the epidemiology of hantavirus infections in Japan and Far East Russia, we conducted epidemiological surveys in these regions. In Japan, anti-hantavirus antibodies were found in four rodent species, Clethrionomys rufocanus, Rattus norvegicus, R. rattus, and Apodemus speciosus. Although no new HFRS cases have been officially reported over the past 20 years in Japan, one member of the Japan Ground Self-Defense Force did test positive for hantavirus antibody. Repeated surveys in Far East Russia have revealed that two distinct hantavirus types cause severe HFRS in this region. Hantavirus sequences identified from A. peninsulae, fetal HFRS cases in Vladivostok, and Amur virus are highly similar to each other (92% identity) , but they are less similar (-84% identity) to the prototypical Hantaan virus, which is carried by A. agrarius. Phylogenetic analysis also indicates that Amur and A. peninsulae -associated viruses are distinct from Hantaan virus, suggesting that A. peninsulae is the reservoir animal for Amur virus, which causes severe HFRS. From HFRS patients in the Khabarovsk region, we identified viruses with nucleotide sequences that are more similar to Far East virus (96%identity) than to the Hantaan (88-89%identity) or Amur (81-83% identity) viruses. Phylogenetic analysis also indicates that the viruses from Khabarovsk HFRS patients are closely related to the Far East virus, and distinct from Amur virus.
Show more [+] Less [-]Oxidative stress and bovine liver diseases: Role of glutathione peroxidase and glucose 6-phosphate dehydrogenase
2007
Ellah, M.R.A.(Iwate Univ., Morioka (Japan). Faculty of Agriculture) | Okada, K. | Yasuda, J.
This article summarizes the different types of free radicals, antioxidants and the effect of oxidative stress on the activities of glutathione peroxidase and glucose 6-phosphate dehydrogenase in bovine liver diseases. A growing body of evidence suggests that the formation of reactive oxygen species is a common occurrence associated with most if not all disease processes. The overall importance of reactive oxygen species to the progression and severity of various disease states varies greatly depending on the conditions and whether the disease is acute or chronic. Free radical researches in animals are in progress and further investigations are needed to establish the involvement of reactive oxygen species in diseases affecting different animal species and the pathology they produce.
Show more [+] Less [-]Epizootiological survey of Trichinella spp. infection in carnivores, rodents and insectivores in Hokkaido, Japan
2007
Kanai, Y.(Hokkaido Univ., Sapporo (Japan)) | Inoue, T. | Mano, T. | Nonaka, N. | Katakura, K. | Oku, Y.
In order to evaluate the present epidemiological situation of Trichinella infection in wild animals in Hokkaido, Japan, red foxes (Vulpes vulpes), raccoon dogs (Nyctereutes procyonoides), brown bears (Ursus arctos), martens (Martes melampus), rodents and insectivores captured in Hokkaido were examined for muscle larvae by the artificial digestion method from 2000 to 2006. Foxes (44/319, 13.8%), raccoon dogs(6/77, 7.8%) and brown bears (4/126, 3.2%) were found to be infected with Trichinella larvae and all other animal species evaluated were negative. Multiplex PCR and DNA sequencing revealed that larvae from a fox captured in Otofuke, in south-eastern Hokkaido, were T. nativa, and larvae from 27 animals including 21 foxes, 2 raccoon dogs and 4 brown bears captured in western Hokkaido were Trichinella T9.
Show more [+] Less [-]Leptin inhibits hepatocyte growth factor-induced ductal morphogenesis of bovine mammary epithelial cells
2007
Yamaji, D.(Hokkaido Univ., Sapporo (Japan)) | Kamikawa, A. | Soliman, M.M. | Ito, T. | Ahmed, M.M. | Makondo, K. | Watanabe, A. | Saito, M. | Kimura, K.
We examined the effect of stroma-derived factors, hepatocyte growth factor (HGF) and leptin, on morphological differentiation of bovine mammary epithelial cells (BMEC) in collagen gel three-dimensional culture in vitro. BMEC treated with HGF, but not leptin, formed duct-like organoids. The formation of organoids by HGF was enhanced by treatment with a mixture of insulin, cortisol and prolactin, while BMEC treated with the mixture alone did not produce the organoid. In contrast, the formation of organoids by HGF was dose-dependently inhibited by simultaneous addition of leptin, regardless of the presence or absence of the hormone mixture. These results suggest that stroma-derived factors intricately regulate mammary epithelial morphogenesis.
Show more [+] Less [-]Lumenal localization in the endoplasmic reticulum of the C-terminal tail of an AE1 mutant responsible for hereditary spherocytosis in cattle
2007
Ito, D.(Hokkaido Univ., Sapporo (Japan)) | Otsuka, Y. | Koshino, I. | Inaba, M.
An R664X nonsense mutant AE1 is responsible for dominant hereditary spherocytosis in cattle and is degraded by the proteasomal endoplasmic reticulum-associated degradation. The present study demonstrated that R664X AE1 translated in vitro had the trypsin-sensitve site identical to that of the wild-type AE1. The P661S/R664X mutant containing a possible N-glycosylation site at Asnsup(660) showed an increase in size by 3 kDa both in the cell-free translation system and in transfected HEK293 cells. Moreover, steady state levels of R664X and P661S/R664X in HEK293 cells were markedly increased in the presence of a proteasome inhibitior. These findings indicate that the truncated C-terminal region of R664X AE1 has lumenal localization in the endoplasmic reticulum and is not accessible to proteasomal machineries in the cytosol.
Show more [+] Less [-]Clinico-pathological findings in peripartum dairy cows fed anion salts lowering the dietary cation-anion difference: Involvement of serum inorganic phosphorus, chloride and plasma estrogen concentrations in milk fever
2007
Kurosaki, N.(Hokkaido Univ., Sapporo (Japan)) | Yamato, O. | Sasamoto, Y. | Mori, F. | Imoto, S. | Kojima, T. | Yamasaki, M. | Maede, Y.
In our previous study, it was demonstrated that the administration of anion salts, which slightly lower the dietary cation-anion difference (DCAD), in the prepartum period is safe and effective for preventing milk fever in multiparous cows. In the present study, several clinico-pathological constituents in serum and urine, which might be related to milk fever, were analyzed using stored samples from the previous study to identify clinico-pathological parameters for easily evaluating the efficacy of lowering DCAD and to further investigate the mechanism by which lowering DCAD prevents milk fever. Among the parameters analyzed in the present study, inorganic phosphorus (iP) was involved in milk fever because the serum concentration and urinary excretion of iP were significantly higher in the group of primiparous cows (heifer group), which did not develop hypocalcemia, than those in other groups of multiparous cows. Serum chloride concentrations in the heifer group and the group of multiparous cows fed anion salts (anion group) tended to remain higher than those in other control groups of multiparous cows suggesting that serum chloride concentration may be utilized for evaluating the status of metabolic acidosis and the efficacy of lowerng DCAD in dairy cows fed anion salts. In addition, plasma estradiol-17beta concentration in the heifer group tended to be lower at parturition compared with that in other multiparous groups suggesting that estrogen known as a potent inhibitor of bone resorption may be involved in developing milk fever.
Show more [+] Less [-]Controle da Artrite-Encefalite Caprina, em um capril comercial endemicamente contaminado Full text
2007
Anee Valéria Mendonça Stachissini | José Rafael Modolo | Roberto Soares de Castro | Barbára Lima Simioni Leite | João Pessoa Araújo Júnior | Carlos Roberto Padovani
A CAE é provocada por um lentivírus. Os animais infectam-se, principalmente, quando mamam colostro e/ou leite contaminados. Neste trabalho, propôs-se um plano de controle da CAE, sem que se sacrificassem as mães contaminadas. Utilizaram-se 39 cabritas, nascidas de mães soropositivas para a CAE. Após o nascimento, as cabritas foram isoladas das mães e alimentadas com colostro de cabras soronegativas, tratado termicamente, e com leite de cabra pasteurizado, até os dois meses. Submeteram-se todas as cabritas ao teste sorológico, trimestralmente, do nascimento aos 12 meses; segregaram-se as soropositivas do rebanho. O grupo controle consistiu de 12 cabritos, nascidos de cabras soropositivas, os quais permaneceram com suas mães. O procedimento de diagnóstico foi o mesmo, mas não foram segregados os positivos. Ao final de 12 meses, 34 (87%) animais do grupo experimental permaneceram soronegativos, com limites de confiança de 76% a 98%; nos animais do grupo controle, a taxa de negatividade acumulada foi de 17%, com limites de confiança entre 0% e 38%. Com esses resultados, conclui-se que o plano proposto é viável para garantir o controle da enfermidade, em rebanhos contaminados, ou seja, a não-adoção do mesmo pode levar à contaminação dos animais nascidos de cabras infectadas.
Show more [+] Less [-]Anatomia microvascular do estômago canino e lesão gástrica provocada por antiinflamatórios não esteróides Full text
2007
Karla Patrícia Cardoso Araújo | Francisco Javier Hernandez Blazquez
Os Antiinflamatórios Não Esteróides (AINEs) inibem a síntese de prostaglandinas, com subseqüente diminuição da secreção de muco e bicarbonato pelo epitélio gástrico, redução da hidrofobicidade da camada epitelial, comprometimento da reposição celular, redução do fluxo sanguíneo e aumento da aderência de neutrófilos. Ao longo dos anos, notou-se que as lesões gástricas provocadas pelo uso de AINEs se localizam com maior freqüência nas regiões do antro pilórico e curvatura menor do estômago. A maior susceptibilidade destas regiões pode ser explicada por sua anatomia microvascular, a qual apresenta capilares estreitos, tortuosos e com menor diâmetro que em outras regiões do estômago; estes são mais separados entre si e há menos anastomoses entre os capilares ascendentes, tornando-os mais predispostos à trombose e conseqüente lesão gástrica.
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