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941.
M. Shamim Hasan ZAHID Sharda Prasad AWASTHI Atsushi HINENOYA Shinji YAMASAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):535-540
To search natural compounds having inhibitory effect on bacterial growth is important,
particularly in view of growing multidrug resistant (MDR) strains of bacterial pathogens.
Like other bacterial pathogens, MDR Vibrio cholerae, the causative agent
of diarrheal disease cholera, is becoming a great concern. As an approach of searching new
antimicrobial agents, here, we show that anethole, a well-studied natural component of
sweet fennel and star anise seeds, could potentially inhibit the growth of MDR O1 El Tor
biotype, the ongoing 7th cholera pandemic variant strains of toxigenic V.
cholerae. The minimum inhibitory concentration (MIC) of anethole against
diverse O1 El Tor biotype strains is evaluated as 200
µg/ml. Moreover, the effect of anethole is
bactericidal and exerts rapid-killing action on V.
cholerae cells. This study is the first report which demonstrates
that anethole, purified from natural compound, is a potent inhibitor of growth of
toxigenic V. cholerae. Our data suggest that anethole could be a
potential antimicrobial drug candidate, particularly against MDR V.
cholerae mediated infections. 相似文献
942.
Arunee THANASARASAKULPONG Pichayanut POOLPERM Pallop TANKAEW Takuo SAWADA Nattawooti STHITMATEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):321-326
Recombinant outer membrane protein H (rOmpH) is a potential fowl cholera vaccine
candidate. The present study was aimed at developing rOmpH formulations for intranasal
administration. The rOmpH was purified and formulated with either Escherichia
coli enterotoxin B (LTB) or CpG oligodeoxynucleotides (ODN) as an adjuvant.
Antibody responses in chickens intranasally immunized with rOmpH in combination with 2
different adjuvants were significantly increased (P<0.05) post
immunization. Chicken survival rates showed that rOmpH formulated with ODN and LTB
elicited 90% and 70% protection, respectively. Our findings indicated that rOmpH
formulated with ODN elicited protection better than that formulated with LTB. Therefore,
the vaccines formulations in the present study can be considered new intranasal vaccine
formulations for fowl cholera in chickens. 相似文献
943.
Zengyang PEI Jinqiu WANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):139-145
Sepsis is a major cause of mortality in intensive care medicine. Propofol, an intravenous general anesthetic, has been suggested to have anti-inflammatory properties and able to prevent sepsis induced by Gram-positive and Gram-negative bacteria by down-regulating the gene expression of pro-inflammatory cytokines. However, propofol’s anti-inflammatory effects upon canine peripheral blood mononuclear cells (PBMCs) have not yet been clarified. Here, we isolate canine PBMCs and investigate the effects of propofol on the gene expressions of both lipopolysaccharide (LPS)-induced interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α and upon the production of nitric oxide (NO). Through real-time quantitative PCR and the Griess reagent system, we found that non-cytotoxic levels of propofol significantly inhibited the release of NO and IL-6 and TNF-α gene expression in LPS-induced canine PBMCs. Western blotting revealed that LPS
does significantly increase the expression of inducible NO synthase (iNOS) protein in canine PBMCs, while pretreatment with propofol significantly decreases the LPS-induced iNOS protein expression. Propofol, at concentration of 25 µM and 50 µM, also significantly inhibited the LPS-induced nuclear translocation of nuclear factor (NF)-κB p65 protein in canine PBMCs. This diminished TNF-α, IL-6 and iNOS expression, and NO production was in parallel to the respective decreased NF-κB p65 protein nuclear translocation in the LPS-activated canine PBMCs pretreated with 25 µM and 50 µM propofol. This suggests that non-cytotoxic levels of propofol pretreatment can down-regulate LPS-induced inflammatory responses in canine PBMCs, possibly by inhibiting the nuclear translocation of the NF-κB p65 protein. 相似文献
944.
Nobukazu SAISHU Kazutaka MORIMOTO Hiroshi YAMASATO Hiroichi OZAKI Toshiyuki MURASE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1037-1042
Thirty-eight Aerococcus viridans isolates were obtained from milk from
478 cows with clinical mastitis in a farm during the periods between November 2011 and
February 2012, and between December 2012 and March 2013. Additional isolates were obtained
from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding
materials. The processed manure was later used to cover the floor of the stalls in barns
as bedding materials. The temperatures recorded in the composted and processed manure were
not as high as those generally observed during satisfactory composting. To reveal the
association of A. viridans in manure-related products with intramammary
infection in cows, isolates were characterized by their DNA fragment patterns as
determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility
testing. Isolates obtained from milk, processed manure and bedding materials had identical
DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from
milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to
clindamycin, whereas virtually all the isolates were susceptible to 12 other
antimicrobials including cefalosporins that have been used to treat bovine mastitis in
Japan. In vitro, three A. viridans isolates from milk
and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high
temperature (50°C). The results suggest that the processed manure and bedding materials in
this farm were possible sources of A. viridans that caused infection in
the cows with mastitis. 相似文献
945.
946.
Fumiko SUZUTA Kumiko KIMURA Ryo URAKAWA Yukio KUSUDA Shogo TANAKA Yasuko HANAFUSA Makoto HARITANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):1029-1031
This report presents a new case of mucormycosis encountered in penguin characterized by morphological variation of hyphae and presence of sporangia with numerous sporangiospores. A 4.5-year-old Magellanic penguin (Spheniscus magellanicus) died after exhibiting anorexia, poor nutritional condition and dyspnea. Multiple nodular lesions were observed in the thoracic and abdominal regions. Histopathologically, hyphae of various sizes were seen in the lungs, air sac and nodular lesions. Myriad sporangiospores and several sporangia were observed in/around the bronchi or parabronchi. The very narrow and short hyphae in the nodules were not consistent with the characteristics of Mucorales. However, for most hyphae, including those in the nodules, sporangiospores and sporangia, immunohistochemistry revealed Mucorales-positive reactions. In addition, these fungi were identified as Rhizomucor pusillus by gene
analysis. 相似文献
947.
948.
Patrizia CASAGRANDE PROIETTI Valentina STEFANETTI Doreene Rose HYATT Maria Luisa MARENZONI Stefano CAPOMACCIO Mauro COLETTI Annalisa BIETTA Maria Pia FRANCIOSINI Fabrizio PASSAMONTI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):945-951
Biofilm-forming ability is increasingly being recognized as an important virulence factor in several Staphylococcus species. This study evaluated the biofilm-forming ability of sixty canine derived clinical isolates of S. pseudintermedius, using three phenotypic methods, microtiter plate test (MtP), Congo red agar method (CRA) and tube adherence test, and the presence and impact of biofilm-associated genes (icaA and icaD). The results showed that icaA and icaD genes were detected concomitantly in 55 (91.7%) of 60 isolates. A majority (88.3%) of the strains screened had matching results by the tube adherence test, MtP and PCR analysis. Better agreement (95%) was found between the PCR-based analysis and the CRA. Results of the icaA and icaD gene PCRs showed good agreement with CRA results, with a kappa of 0.7. Comparing the phenotypic methods,
the statistical analysis showed that the agreement among the phenotypical tests using categorical data was generally good. Considering two classes (biofilm producer and biofilm non-producer), the percentage of matching results between the CRA method and the tube adherence test and between the CRA method and the MtP was 93.3%. A concordance of 100% was revealed between the MtP and the tube adherence test. The results indicate a high prevalence of the ica genes within S. pseudintermedius isolates, and their presence is associated with in vitro formation of a biofilm. A combination of phenotypic and genotypic tests is recommended for investigating biofilm formation in S. pseudintermedius. 相似文献
949.
Ryota MATSUYAMA Naotoshi KUNINAGA Tomoya MORIMOTO Tetsuya SHIBANO Akiko SUDO Kazunari SUDO Makoto ASANO Masatsugu SUZUKI Tetsuo ASAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1179-1181
Plesiomonas shigelloides is a causal agent of gastroenteritis, sepsis
and meningitis in humans. We examined the prevalence of P. shigelloides
among great cormorants (Phalacrocorax carbo hanedae) in Japan and the
antimicrobial susceptibility of isolates. P. shigelloides was isolated
from 33 (47.8%) of 69 fecal samples from great cormorants in 2014. All 33 isolates were
subjected to antimicrobial susceptibility testing using broth microdilution methods, which
showed resistance to ampicillin (31 isolates, 93.9%), tetracycline (two isolates, 6.1%)
and trimethoprim (one isolate, 3.0%). The high prevalence of P.
shigelloides in the great cormorants implicates the possible microbiological
risk to public health. 相似文献
950.
Kartika DEWI Hideo HASEGAWA Yuli Sulistya FITRIANA Mitsuhiko ASAKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1217-1222
The present report describes Syphacia
(Syphacia) maxomyos sp. n. (Nematoda:
Oxyuridae) from two species of spiny rats, Maxomys musschenbroekii from
Sulawesi and M. whiteheadi from Sumatra. It is characterized by a
cephalic plate extending laterally with dorsoventral constriction and stumpy eggs with an
operculum rim reaching pole. It is readily distinguishable by the former feature from all
of hitherto known representatives of this genus in Indonesia, but it resembles parasites
in Murini and Hydromyni rodents in continental Asia and Sahul. This is the first
Syphacia species distributed in both the Sunda Shelf and Sulawesi with
the exception of Syphacia muris, a cosmopolitan pinworm found in rodents
of the of genus Rattus. It is surmised that S. maxomyos
is specific to Maxomys and that it was introduced to Sulawesi by
dispersal of some Maxomys from the Sunda Shelf. 相似文献