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1.
Jin HUR Seong Kug EO Sang-Youel PARK Yoonyoung CHOI John Hwa LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1693-1696
Salmonella Typhimurium strain expressing the Actinobacillus
pleuropneumoniae antigens, ApxIA, ApxIIA, ApxIIIA and OmpA, was previously
constructed as a vaccine candidate for porcine pleuropneumonia. This strain was a live
attenuated (∆lon∆cpxR∆asd)Salmonella as a delivery host
and contained a vector containing asd. An immunological study of
lymphocyte proliferation, T-lymphocyte subsets and cytokines in the splenocytes of a mouse
model was carried out after stimulation with the candidate Salmonella
Typhimurium by intranasal inoculation. The splenic lymphocyte proliferation and the levels
of IL-4, IL-6 and IL-12 of the inoculated mice were significantly increased, and the T-
and B-cell populations were also elevated. Collectively, the candidate may efficiently
induce the Th1- and Th2-type immune responses. 相似文献
2.
Salmonella Typhimurium and S. Stanley are the most prevalent serogroup B serovars to infect humans in Taiwan. The aim was to determine possible factors to influence the prevalence between S. Typhimurium and S. Stanley. Genotypes were determined by pulsed field gel electrophoresis (PFGE) analysis and the intracellular survival, phagocytosis, reactive oxygen species (ROS) production of human monocyte THP-1 cell and tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and IL-1βexpression in peripheral blood CD14+ cells after infection were analyzed. 182 S. Stanley was clonal disseminated with main pulsotypes 2 from 2004 to 2007. Overall S. Typhimurium evolved more genotypes, while S. Stanley conserved in genotypes. Human blood CD14+ monocytes expressed TNF-α, IL-6 and IL-1β differently among serovars and bacterial conditions (live vs. killed). Live S. Stanley and S. Typhimurium suppressed the TNF-α and IL-6 expression compared to killed bacteria. However, live S. Typhimurium stimulated more IL-1β expression than the killed bacteria, but S. Stanley expressed similar IL-1β levels in both conditions. Furthermore, S. Stanley and S. Typhimurium differed in intracellular survival in the THP-1 cells, an early decrease for S. Stanley, not for S. Typhimurium. Additionally, higher reactive oxygen species (ROS) production in THP-1 cells was found agsinst S. Stanley infection, not found in S. Typhimurium. However, some isolates of S. Stanley could recover from early loss to become more in the monocytes than S. Typhimurium. Difference in phagocytized number, intracellular survival, ROS production and IL-1β expression may contribute to prevalence different between two serovars. 相似文献
3.
Petra Ondrackova Katerina Nechvatalova Zdenka Kucerova Lenka Leva Javier Dominguez Martin Faldyna 《Veterinary research》2010,41(5)
Mononuclear phagocytes (MP) are cells of nonspecific immunity, playing an essential role in defense against bacterial pathogens. Although various MP subpopulations have been described in the pig, relations among these populations in vivo are unknown to date. The present study was aimed at describing porcine MP subpopulations infiltrating inflamed tissue of pigs under in vivo conditions. Actinobacillus pleuropneumoniae (APP) infection was used to induce an inflammatory response. CD172α, CD14, CD163, MHCII and CD203α cell surface molecules were used to identify MP by flow cytometry. Changes in MP subpopulations in the peripheral blood (PB) and bone marrow (BM) compartments along with the analysis of MP appearing in the inflamed lungs were assessed to elucidate the possible origin and maturation stages of the infiltrating MP. The MP population migrating to the inflamed lungs was phenotype CD14+ CD163+ CD203α+/− MHCII+/−. Concomitantly, after APP infection there was an increase in the PB MP CD14+ CD163+ CD203α− MHC II− population, suggesting that these cells give rise to inflammatory monocytes/macrophages. The CD203α and MHCII molecules appear on these cells after leaving the PB. In healthy animals, the BM MP precursors were represented by CD14− CD163− cells maturing directly into CD14+ CD163− that were then released into the PB. After infection, an altered maturation pathway of MP precursors appeared, represented by CD14− CD163− CD203α− MHCII− MP directly switching into CD14+ CD163+ CD203α− MHCII− MP. In conclusion, two different MP maturation pathways were suggested in pigs. The use of these pathways differs under inflammatory and noninflammatory conditions. 相似文献
4.
Su Hwa Lee Byeong Yeal Jung Nabin Rayamahji Hee Soo Lee Woo Jin Jeon Kang Seuk Choi Chang Hee Kweon Han Sang Yoo 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):43-51
Salmonella (S.) Typhimurium and S. Enteritidis are the major causative agents of food-borne illnesses worldwide. Currently, a rapid detection system using multiplex real-time polymerase chain reaction (PCR) has been applied for other food-borne pathogens such as Escherichia coli, Staphylococcus aureus and Streptococcus spp. A multiplex real-time PCR was developed for the simultaneous detection of Salmonella spp., especially S. Typhimurium and S. Enteritidis, in beef and pork. For the specific and sensitive multiplex real-time PCR, three representative primers and probes were designed based on sequence data from Genbank. Among the three DNA extraction methods (boiling, alkaline lysis, and QIAamp DNA Mini Kit), the QIAamp DNA Mini Kit was the most sensitive in this study. The optimized multiplex real-time PCR was applied to artificially inoculated beef or pork. The detection sensitivity of the multiplex real-time PCR was increased. The specificity of the multiplex real-time PCR assay, using 128 pure-cultured bacteria including 110 Salmonella isolates and 18 non-Salmonella isolates, was 100%, 100% and 99.1% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The sensitivity was 100%, 100% and 91.7% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The multiplex real-time PCR assay developed in this study could detect up to 0.54 ± 0.09 and 0.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for beef, 1.45 ± 0.21 and 1.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for pork, respectively, with all conditions optimized. Our results indicated that the multiplex real-time PCR assay developed in this study could sensitively detect Salmonella spp. and specifically differentiate S. Typhimurium from S. Enteritidis in meats. 相似文献
5.
Ki-Eun LEE Deog-Yong LEE Hwan-Won CHOI Su-Jin CHAE Young-Sun YUN Ki-Chan LEE Yun-Sang CHO Dong-Kun YANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1511-1515
Between 2011 and 2012, a total of 896 pig fecal samples were collected from nine
provinces in Korea, and 50 salmonella enterica susp.
enterica serovar Typhimurium (S. Typhimurium) was
isolated. The characteristics of the 50 strains were analyzed, and 4 strains were
identified as Salmonella enterica subsp. enterica
serovar 4,[5],12:i:-. Salmonella 4,[5],12:i:- could not be distinguished
from S. Typhimurium through phage typing, antimicrobial resistance
testing or multiple-locus variable-number tandem repeat analysis (MLVA). However, among
the four Salmonella 4,[5],12:i:- strains, one (KVCC-BA1400078) was
identified as a Salmonella 4,[5],12:i:- clone isolated from humans in the
United States, and another (KVCC-BA1400080) was identified as DT193, which has been
primarily isolated from humans and animals in European countries. The presence of
Salmonella 4,[5],12:i:- in Korea poses a significant threat of
horizontal transfer between pigs and humans. 相似文献
6.
Noriko IDO Kaori IWABUCHI Yusuke SATO’O Yasuo SATO Masaru SUGAWARA Gakuji YAEGASHI Masaru KONNO Masato AKIBA Kiyoshi TANAKA Katsuhiko OMOE Ikuo UCHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):609-613
Fifty-one Salmonella enterica serovar 4,[5],12:i:-
(S. 4, [5],12:i:-) isolates (14 human strains, 34 animal strains and 3
river water strains) which are assumed to be monophasic variants of S.
Typhimurium were analyzed using pulsed-field gel electrophoresis (PFGE) and multiple-locus
variable-number tandem repeat analysis (MLVA) in order to investigate their genetic
diversities and relationships. PFGE, MLVA and combination of them identified 28, 27 and 34
profiles (Simpson’s diversity indices [DI]=0.94, 0.96 and 0.97), respectively. No
correlations were detected between MLVA clustering and PFGE clustering or phage typing.
These results suggested that S. 4,[5],12:i:- originated from multiple
S. Typhimurium ancestors. Two cattle and one pig isolates showing
identical phage types as well as PFGE and MLVA profiles to human isolates
S. 4,[5],12:i:- suggested the existence of the links between human
infections and animal reservoirs. 相似文献
7.
Pengcheng LI Yunfeng LI Guoqing SHAO Qinghua YU Qian YANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):519-525
The aim of this study was to evaluate the immune responses to intranasal and
intrapulmonary vaccinations with the attenuated Mycoplasma hyopneumoniae
(Mhp) 168 strain in the local respiratory tract in pigs. Twenty-four
pigs were randomly divided into 4 groups: an intranasal immunization group, an
intrapulmonary immunization group, an intramuscular immunization group and a control
group. The levels of local respiratory tract cellular and humoral immune responses were
investigated. The levels of interleukin (IL)-6 in the early stage of immunization
(P<0.01), local specific secretory IgA (sIgA) in nasal swab samples
(P<0.01); and IgA- and IgG-secreting cells in the nasal mucosa and
trachea were higher after intranasal vaccination (P<0.01) than in the
control group. Interestingly, intrapulmonary immunization induced much stronger immune
responses than intranasal immunization. Intrapulmonary immunization also significantly
increased the secretion of IL-6 and local specific sIgA and the numbers of IgA- and
IgG-secreting cells. The levels of IL-10 and interferon-γ in the nasal swab samples and
the numbers of CD4+ and CD8+ T lymphocytes in the lung and hilar
lymph nodes were significantly increased by intrapulmonary immunization compared with
those in the control group (P<0.01). These data suggest that
intrapulmonary immunization with attenuated Mhp is effective in evoking
local cellular and humoral immune responses in the respiratory tract. Intrapulmonary
immunization with Mhp may be a promising route for defense against
Mhp in pigs. 相似文献
8.
Yamato SAJIKI Satoru KONNAI Reiko NAGATA Satoko KAWAJI Hayato NAKAMURA Sotaro FUJISAWA Tomohiro OKAGAWA Naoya MAEKAWA Yukinari KATO Yasuhiko SUZUKI Shiro MURATA Yasuyuki MORI Kazuhiko OHASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):162
Johne’s disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic enteritis of ruminants. Previous studies have shown that programmed death-ligand 1 (PD-L1) is associated with the disease progression, and PD-L1 blockade activates MAP-specific Th1 responses in vitro. Here, we performed anti-PD-L1 antibody administration using 2 MAP-infected cattle at the late subclinical stage of infection. After administration, bacterial shedding was reduced or maintained at a low level. Additionally, MAP-specific Th1 cytokine production was upregulated, and CD69 expression was increased in T cells. Collectively, the treatment has a potential as a novel control method against Johne’s disease. 相似文献
9.
Brucella canis is a small intracellular Gram-negative bacterium that frequently leads to chronic infections highly resistant to antibiotic therapy in dogs. Also, it causes mild human brucellosis compared to other zoonotic Brucella spp. Herein we characterize the cellular immune response elicited by B. canis by analysing human and canine CD4+ T cells after stimulation with autologous monocyte-derived dendritic cells (MoDCs). Human and canine B. canis-primed MoDCs stimulated autologous CD4+ T cells; however, a Th1 response was triggered by human MoDCs, whereas canine MoDCs induced Th1/Th17 responses, with increased CD4+ T cells producing IFN-γ and IL-17A simultaneously. Each pattern of cellular response may contribute to host susceptibility, helping to understand the differences in B. canis virulence between these two hosts. In addition, other aspects of canine immunology are unveiled by highlighting the participation of IL-17A-producing canine MoDCs and CD4+ T cells producing IFN-γ and IL-17A. 相似文献
10.
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
11.
12.
Hidenori MATSUI Yasunori ISSHIKI Masahiro EGUCHI Yohsuke OGAWA Yoshihiro SHIMOJI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):181-186
We evaluated the protective efficacy of 94-kb virulence plasmid-cured, and phoP- or aroA-deficient strains of Salmonella enterica serovar Typhimurium (ΔphoP or ΔaroA S. Typhimurium) as oral vaccine candidates in BALB/c mice. Two weeks after the completion of 3 oral immunizations with 1 × 108 colony-forming units (CFU) of virulence plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium at 10-day intervals, S. Typhimurium lipopolysaccharide (LPS)-specific mucosal secretory immunoglobulin A (s-IgA) antibody titers were detected in the cecal homogenate, bile and lung lavage fluid, but not in the intestinal lavage fluid. In addition, the increases in S. Typhimurium LPS-specific immunoglobulin G (IgG) and IgA antibody titers in the serum were also observed 2 weeks after completing 3 oral immunizations with virulence
plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium. The series of 3 oral immunizations protected the mice against an oral challenge with 5 × 108 CFU of the virulent strain of S. Typhimurium, suggesting that both the virulence plasmid-cured, and ΔphoP and ΔaroA S. Typhimurium strains are promising candidates for safe and effective live S. Typhimurium vaccines. 相似文献
13.
Masanao MATAYOSHI Takashi KITANO Tetsu SASAKI Masaji NAKAMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):705-710
A total of 349 Salmonella enterica subspecies enterica
serovar Choleraesuis (S. Choleraesuis) strains, which were isolated
between 2008 and 2012 from 349 pigs at two slaughterhouses in Okinawa Prefecture, Japan,
were investigated for antimicrobial susceptibility and the presence of antimicrobial
resistance genes. All isolates were resistant to at least four antimicrobial agents. The
antimicrobial agents for which isolates showed a high incidence of resistance were as
follows: ampicillin (100%) and streptomycin (100%), followed by gentamicin (99.7%),
oxytetracycline (99.7%), sulfamethoxazole/trimethoprim (99.4%), nalidixic acid (40.1%) and
oxolinic acid (40.1%). All isolates were sensitive to cefuroxime, ceftiofur, colistin,
fosfomycin, enrofloxacin, orbifloxacin and danofloxacin. The predominant resistance
phenotypes and genotypes were: resistance to ampicillin, streptomycin, gentamicin,
oxytetracycline and sulfamethoxazole/trimethoprim (58.5%, 204/349) and
blaTEM-strA-strB-aadA1-aadA2-aacC2-tet
(B)-sul1-sul2-dhfrXII-dhfrXIII (36.1%, 126/349). The quinolone
resistance-determining regions (QRDRs) of gyrA, gyrB, parC and
parE of the quinolone-resistant isolates (n=12) showed amino acid
substitutions of Ser-83→Phe or Asp-87→Tyr in GyrA and Ser-107→Ala in ParC. To our
knowledge, this is the first report on the molecular characterization of antimicrobial
resistance among S. Choleraesuis strains in Japan. 相似文献
14.
Haiyan Zhao Yalan Wang Zhitao Ma Yongqiang Wang Wen-hai Feng 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(2):199-208
Currently, killed-virus and modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccines are used to control porcine reproductive and respiratory syndrome. However, both types of vaccines have inherent drawbacks; accordingly, the development of novel PRRSV vaccines is urgently needed. Previous studies have suggested that yeast possesses adjuvant activities, and it has been used as an expression vehicle to elicit immune responses to foreign antigens. In this report, recombinant Kluyveromyces lactis expressing GP5 of HP-PRRSV (Yeast-GP5) was generated and immune responses to this construct were analyzed in mice. Intestinal mucosal PRRSV-specific sIgA antibody and higher levels of IFN-γ in spleen CD4+ and CD8+ T cells were induced by oral administration of Yeast-GP5. Additionally, Yeast-GP5 administered subcutaneously evoked vigorous cell-mediated immunity, and PRRSV-specific lymphocyte proliferation and IFN-γ secretion were detected in the splenocytes of mice. These results suggest that Yeast-GP5 has the potential for use as a vaccine for PRRSV in the future. 相似文献
15.
Yong Ho Park Sang Un Lee Witold A. Ferens Sparrow Samuels William C. Davis Lawrence K. Fox Jong Sam Ahn Keun Seok Seo Byoung Sun Chang Sun Young Hwang Gregory A. Bohach 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(3):233-239
We previously demonstrated that stimulation of bovine peripheral blood mononuclear cells (PBMCs) with staphylococcal enterotoxin C (SEC), led to an inversion of the CD4+:CD8+ T cell ratio and generation of an atypical CD8+ T cell subpopulation expressing CD26. In the present study, we examined T cell apoptosis and proliferation profiles of PBMC subpopulations in cultures stimulated with SEC. Unlike when stimulated with concanavalin A, nucleic acid synthesis in bovine PBMC cultures stimulated with SEC was low during the first four days but increased greatly on day 5. In contrast, nucleic acid synthesis in human PBMC cultures stimulated with SEC increased continuously. To investigate the mechanism of delayed bovine T cell proliferation, various cell phenotypes were monitored. The inversion of the bovine CD4+:CD8+ T cell ratio in PBMC cultures stimulated by SEC was associated with higher proliferation and lower apoptosis of CD8+ T cells compared to CD4+ T cells. The mRNA levels for interleukin (IL)-4 and IL-13 were sustained over 4 days but IL-12 mRNA levels dropped to background on day 2. These data suggest that SEC induces a prolonged Th-2-biased microenvironment, and together with the inversion of the bovine CD4+:CD8+ T cell ratios in bovine PBMC cultures with SEC, may in part explain the inability of the mammary immune system to establish an effective response to Staphylococcus aureus infections. 相似文献
16.
Mohamed M’BAYE Guohua HUA Hamid Ali KHAN Liguo YANG 《The Journal of reproduction and development》2015,61(5):391-397
Inhibins are members of the TGFβ superfamily and act as suppressors
of follicle stimulating hormone (FSH) secretion from pituitary glands
via a negative feedback mechanism to regulate folliculogenesis. In
this study, the INHBB gene was knocked down by three
RNAi-Ready pSIREN-RetroQ-ZsGreen vector- mediated recombinant plasmids
to explore the effects of INHBB silencing on
granulosa cell (GC) cell cycle, apoptosis and steroid production
in vitro. Quantitative real-time polymerase chain
reaction, Western blot, flow cytometry and ELISA were performed to
evaluate the role of INHBB in the mouse GC cell
cycle, apoptosis and steroid production in vitro. The
results showed that the relative mRNA and protein expression of
INHBB in mouse GCs can be significantly reduced by
RNAi with pshRNA-B1, pshRNA-B2 and pshRNA-B3 plasmids, with pshRNA-B3
having the best knockdown efficiency. Downregulation of the expression
of INHBB significantly arrests cells in the G1 phase
of the cell cycle and increases the apoptosis rate in GCs. This was
further confirmed by downregulation of the protein expressions of
Cyclin D1, Cyclin E and Bcl2, while the protein expression of Bax was
upregulated. In addition, specific downregulation of
INHBB markedly decreased the concentration of
estradiol and progesterone, which was further validated by the
decrease in the mRNA levels of CYP19A1and
CYP11A1. These findings suggest that inhibin βB is
important in the regulation of apoptosis and cell cycle progression in
granulosa cells. Furthermore, the inhibin βB subunit has a role in the
regulation of steroid hormone biosynthesis. Evidence is accumulating
to support the concept that inhibin βB is physiologically essential
for early folliculogenesis in the mouse. 相似文献
17.
Hsien Yueh Liu Chih-Yao Chung Wen-Chin Yang Chih-Lung Liang Chi-Young Wang Chih-Yu Chang Cicero Lee-Tian Chang 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(3):245-252
The incidence of diabetes mellitus is increasing among companion animals. This disease has similar characteristics in both humans and animals. Diabetes is frequently identified as an independent risk factor for infections associated with increased mortality. In the present study, homozygous diabetic (db/db) mice were infected with Listeria (L.) monocytogenes and then treated with the anti-diabetic drug exendin-4, a glucagon-like peptide 1 analogue. In aged db/db mice, decreased CD11b+ macrophage populations with higher lipid content and lower phagocytic activity were observed. Exendin-4 lowered high lipid levels and enhanced phagocytosis in macrophages from db/db mice infected with L. monocytogenes. Exendin-4 also ameliorated obesity and hyperglycemia, and improved ex vivo bacteria clearance by macrophages in the animals. Liver histology examined during L. monocytogenes infection indicated that abscess formation was much milder in exendin-4-treated db/db mice than in the control animals. Moreover, mechanistic studies demonstrated that expression of ATP binding cassette transporter 1, a sterol transporter, was higher in macrophages isolated from the exendin-4-treated db/db mice. Overall, our results suggest that exendin-4 decreases the risk of infection in diabetic animals by modifying the interaction between intracellular lipids and phagocytic macrophages. 相似文献
18.
Narong TIPTANAVATTANA Araya RADTANAKATIKANON Poul HYTTEL Hanne HOLM Supranee BURANAPRADITKUN Piyathip SETTHAWONG Mongkol TECHAKUMPHU Theerawat THARASANIT 《The Journal of reproduction and development》2015,61(6):581-588
The development of germ cells has not been entirely documented in the cat especially the transition phase of
the gonocyte to the spermatogonial stem cell (G/SSC). The aims of study were to examine testicular development
and to identify the G/SSC transition in order to isolate and culture SSCs in vitro. Testes
were divided into 3 groups according to donor age (I, < 4 months; II, 4–6 months; and III, > 6 months).
In Exp. 1, we studied testicular development by histology, transmission electron microscopy and
immunohistochemistry. In Exp. 2, we determined the expression of GFRα-1, DDX-4 and c-kit and performed flow
cytometry. The SSCs isolated from groups II and III were characterized by RT-PCR and TEM (Exp. 3).
Chronological changes in the G/SSC transition were demonstrated. The size, morphology and ultrastructure of
SSCs were distinguishable from those of gonocytes. The results demonstrated that group II contained the
highest numbers of SSCs per seminiferous cord/tubule (17.66 ± 2.20%) and GFRα-1+ cells (14.89 ±
5.66%) compared with the other groups. The findings coincided with an increased efficiency of SSC derivation
in group II compared with group III (74.33 ± 2.64% vs. 23.33 ± 2.23%). The colonies expressed
mRNA for GFRA1, ZBTB16, RET and POU5F1.
Our study found that the G/SSC transition occurs at 4–6 months of age. This period is useful for isolation and
improves the establishment efficiency of cat SSCs in vitro. 相似文献
19.
Seung-Won YI Tae-Ho CHUNG Seong-Joon JOH Chul PARK Byoung-Yong PARK Gee-Wook SHIN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(12):1589-1593
The prevalence of resistant
genes against β-lactams in 119 Aeromonas strains was determined. A large
number (99.2%) of the present fish strains were resistant to one or more β- lactams
including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and
cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all
β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of
A. dhakensis, 8 strains of A. caviae, 2 strains of
A. hydrophila and only one strain of A. veronii. For
exploring genetic background of the antibiotic resistances, multiple PCR assays were
subjected to detect β-lactamase-encoding genes, blaTEM,
blaOXA-B and blaCTX-M. In the
results, the blaTEM-1 gene was harbored in all strains,
whereas only 3 strains harbored blaOXA gene. In the case of
blaCTX-M gene, the gene was detected in 21.0% (25 out of
119) of all strains, which countered with 80% (20 out of 25) of A.
dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25)
of A. hydrophila. In addition, most of the
blaCTX-M positive strains showed simultaneous resistance to
all β-lactams (18 out of 30 strains). In sequence analysis for
blaCTX-M genes detected, they were CTX-M group 1-encoding
genes including blaCTX-M-33 from 3 eel strains of A.
dhakensis. Therefore, A. dhakensis obtained from cultured fish
could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence
should be carefully monitored, especially for its potential risk to public health. 相似文献
20.
Toxocara canis is regarded as the main cause of human toxocarosis but the relative contribution of T. cati is probably underestimated; serological and other diagnostic methods used in most studies of this zoonotic disease do not distinguish between the two parasites. The definitive hosts for T. canis are caniidae. Pups generally have higher infection rates than adult animals and are a major source of eggs in the environment. Humans usually acquire T. canis infection by accidental ingestion of embryonated eggs or encapsulated larvae from the environment or contaminated food, such infections may lead to visceral larva migrans (VLM), ocular larva migrans (OLM) or covert toxocarosis (CT). Although a mixed Th1- and Th2-mediated immunological response, particularly with high levels of IgE and eosinophilia is observed, the underlying mechanisms of molecular and immunopathogenesis for the development of the symptomatic syndromes of VLM, OLM, or of asymptomatic CT are largely unclear. Studies have indicated that immunological defences against various infectious diseases may be highly influenced by complex interactions of environmental and host genetic factors e.g. MHC class I and II, also known as human leucocyte antigen (HLA). Toxocara spp. infections are associated with a polarized CD4+ Th2 response with high IgE levels and eosinophilia, mediated mainly by HLA class II molecules. Associations have been made between HLA class II and pathological severity and host genetic effects on exposure to infection. Recent research suggests Foxp3+ CD4+CD25+-expressing T regulatory (Treg) cells play a role in regulation of the immunopathology of granulomas in experimental toxocaral granulomatous hepatitis and in enhanced expression of TGF-β1, which is an important factor for the local survival and function of Treg observed during T. canis invasion in the mouse small intestine, liver, muscle, and brain. Since the potential susceptibility loci HLA class II molecules, are considered involved in the regulation of a Th2-dominant immunity which is highly controlled by Foxp3+ CD4+CD25+ Treg cells by stimulation through TGF-β1, which thus provides a beneficial environment to T. canis larvae but severe injuries to local organs. However, TGF-β1 variant Leu10Pro known to be involved in disease severity warrants further elucidation as this too may have a role in the severity of human toxocarosis. Exploration of TGF-β1 polymorphism, Foxp3+ CD4+CD25+ Treg cells, and MHC polymorphisms may allow insight into the contribution made by environmental and genetic factors in influencing disease syndrome type and severity in humans with toxocarosis. 相似文献