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1.
Jae Yeon HWANG Kwang-Hwan CHOI Dong-Kyung LEE Seung-Hun KIM Eun Bae KIM Sang-Hwan HYUN Chang-Kyu LEE 《The Journal of reproduction and development》2015,61(6):533-540
X-chromosome inactivation (XCI) is an epigenetic process that equalizes expression of X-borne genes between
male and female eutherians. This process is observed in early eutherian embryo development in a
species-specific manner. Until recently, various pluripotent factors have been suggested to regulate the
process of XCI by repressing XIST expression, which is the master inducer for XCI. Recent
insights into the process and its regulation have been restricted in mouse species despite the evolutionary
diversity of the process and molecular mechanism among the species. OCT4A is one of the
represented pluripotent factors, the gate-keeper for maintaining pluripotency, and an XIST
repressor. Therefore, in here, we examined the relation between OCT4A and X-linked genes in
porcine preimplantation embryos. Three X-linked genes, XIST,
LOC102165544, and RLIM, were selected in present study because their
orthologues have been known to regulate XCI in mice. Expression levels of OCT4A were
positively correlated with XIST and LOC102165544 in female blastocysts.
Furthermore, overexpression of exogenous human OCT4A in cleaved parthenotes generated
blastocysts with increased XIST expression levels. However, increased XIST
expression was not observed when exogenous OCT4A was obtained from early blastocysts. These
results suggest the possibility that OCT4A would be directly or indirectly involved in
XIST expression in earlier stage porcine embryos rather than blastocysts. 相似文献
2.
Takashi FUJII Nobuyuki SAKURAI Tsubasa OSAKI Gentaro IWAGAMI Hiroki HIRAYAMA Akira MINAMIHASHI Tsutomu HASHIZUME Ken SAWAI 《The Journal of reproduction and development》2013,59(2):151-158
In mouse embryos, segregation of the inner cell mass (ICM) and trophectoderm (TE)
lineages is regulated by genes, such as OCT-4, CDX2 and
TEAD4. However, the molecular mechanisms that regulate the segregation
of the ICM and TE lineages in porcine embryos remain unknown. To obtain insights regarding
the segregation of the ICM and TE lineages in porcine embryos, we examined the mRNA
expression patterns of candidate genes, OCT-4, CDX2,
TEAD4, GATA3, NANOG,
FGF4, FGFR1-IIIc and FGFR2-IIIc, in
blastocyst and elongated stage embryos. In blastocyst embryos, the expression levels of
OCT-4, FGF4 and FGFR1-IIIc were
significantly higher in the ICM than in the TE, while the CDX2,
TEAD4 and GATA3 levels did not differ between the ICM
and TE. The expression ratio of CDX2 to OCT-4
(CDX2/OCT-4) also did not differ between the ICM and
TE at the blastocyst stage. In elongated embryos, OCT-4,
NANOG, FGF4 and FGFR1-IIIc were
abundantly expressed in the embryo disc (ED; ICM lineage), but their expression levels
were very low in the TE. In contrast, the CDX2, TEAD4
and GATA3 levels were significantly higher in the TE than in the ED. In
addition, the CDX2/OCT-4 ratio was markedly higher in
the TE than in the ED. We demonstrated that differences in the expression levels of
OCT-4, CDX2, TEAD4,
GATA3, NANOG, FGF4,
FGFR1-IIIc and FGFR2-IIIc genes between ICM and TE
lineages cells become more clear during development from porcine blastocyst to elongated
embryos, which indicates the possibility that in porcine embryos, functions of ICM and TE
lineage cells depend on these gene expressions proceed as transition from blastocyst to
elongated stage. 相似文献
3.
4.
Luciana Rossi Alessia Di Giancamillo Serena Reggi Cinzia Domeneghini Antonella Baldi Vittorio Sala Vittorio Dell'Orto Annelies Coddens Eric Cox Corrado Fogher 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):263-270
Verocytotoxic Escherichia (E.) coli strains are responsible for swine oedema disease, which is an enterotoxaemia that causes economic losses in the pig industry. The production of a vaccine for oral administration in transgenic seeds could be an efficient system to stimulate local immunity. This study was conducted to transform tobacco plants for the seed-specific expression of antigenic proteins from a porcine verocytotoxic E. coli strain. Parameters related to an immunological response and possible adverse effects on the oral administration of obtained tobacco seeds were evaluated in a mouse model. Tobacco was transformed via Agrobacteium tumefaciens with chimeric constructs containing structural parts of the major subunit FedA of the F18 adhesive fimbriae and VT2e B-subunit genes under control of a seed specific GLOB promoter. We showed that the foreign Vt2e-B and F18 genes were stably accumulated in storage tissue by the immunostaining method. In addition, Balb-C mice receiving transgenic tobacco seeds via the oral route showed a significant increase in IgA-positive plasma cell presence in tunica propria when compared to the control group with no observed adverse effects. Our findings encourage future studies focusing on swine for evaluation of the protective effects of transformed tobacco seeds against E. coli infection. 相似文献
5.
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
6.
Sun Young Hwang Young Kyung Park Hye Cheong Koo Yong Ho Park 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(2):125-131
Staphylococcus aureus is a major etiological pathogen of bovine mastitis, which triggers significant economic losses in dairy herds worldwide. In this study, S. aureus strains isolated from the milk of cows suffering from mastitis in Korea were investigated by spa typing and staphylococcal enterotoxin (SE) gene profiling. Forty-four S. aureus strains were isolated from 26 farms in five provinces. All isolates grouped into five clusters and two singletons based on 14 spa types. Cluster 1 and 2 isolates comprised 38.6% and 36.4% of total isolates, respectively, which were distributed in more than four provinces. SE and SE-like toxin genes were detected in 34 (77.3%) isolates and the most frequently detected SE gene profile was seg, sei, selm, seln, and selo genes (16 isolates, 36.3%), which was comparable to one of the genomic islands, Type I νSaβ. This is a first report of spa types and the prevalence of the recently described SE and SE-like toxin genes among S. aureus isolates from bovine raw milk in Korea. Two predominant spa groups were distributed widely and recently described SE and SE-like toxin genes were detected frequently. 相似文献
7.
Tan Duc Nguyen Thin Thanh Vo Hung Vu-Khac 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(2):159-164
This study was conducted to determine the prevalence and characteristics of pathogenic Escherichia (E.) coli strains from diarrheic calves in Vietnam. A total of 345 E. coli isolates obtained from 322 diarrheic calves were subjected to PCR and multiplex PCR for detection of the f5, f41, f17, eae, sta, lt, stx1, and stx2 genes. Of the 345 isolates, 108 (31.3%) carried at least one fimbrial gene. Of these 108 isolates, 50 carried genes for Shiga toxin and one possessed genes for both enterotoxin and Shiga toxin. The eae gene was found in 34 isolates (9.8%), 23 of which also carried stx genes. The Shiga toxin genes were detected in 177 isolates (51.3%) and the number of strains that carried stx1, stx2 and stx1/stx2 were 46, 73 and 58, respectively. Among 177 Shiga toxin-producing E. coli isolates, 89 carried the ehxA gene and 87 possessed the saa gene. Further characterization of the stx subtypes showed that among 104 stx1-positive isolates, 58 were the stx1c variant and 46 were the stx1 variant. Of the 131 stx2-positive strains, 48 were stx2, 48 were stx2c, 11 were stx2d, 17 were stx2g, and seven were stx2c/stx2g subtypes. The serogroups most prevalent among the 345 isolates were O15, O20, O103 and O157. 相似文献
8.
Yan Jun HUAN Jiang ZHU Bing Teng XIE Jian Yu WANG Shi Chao LIU Yang ZHOU Qing Ran KONG Hong Bin HE Zhong Hua LIU 《The Journal of reproduction and development》2013,59(5):442-449
The efficiency of cloning by somatic cell nuclear transfer (SCNT) has remained low.
In most cloned embryos, epigenetic reprogramming is incomplete, and usually the
genome is hypermethylated. The DNA methylation inhibitor 5-aza-2’-deoxycytidine
(5-aza-dC) could improve the developmental competence of cow, pig, cat and human SCNT
embryos in previous studies. However, the parameters of 5-aza-dC treatment among
species are different, and whether 5-aza-dC could enhance the developmental
competence of porcine cloned embryos has still not been well studied. Therefore, in
this study, we treated porcine fetal fibroblasts (PFF) that then were used as donor
nuclei for nuclear transfer or fibroblast-derived reconstructed embryos with
5-aza-dC, and the concentration- and time-dependent effects of 5-aza-dC on porcine
cloned embryos were investigated by assessing pseudo-pronucleus formation,
developmental potential and pluripotent gene expression of these reconstructed
embryos. Our results showed that 5-aza-dC significantly reduced the DNA methylation
level in PFF (0 nM vs. 10 nM vs. 25 nM
vs. 50 nM, 58.70% vs. 37.37%
vs. 45.43% vs. 39.53%, P<0.05), but did not
improve the blastocyst rate of cloned embryos derived from these cells. Treating
cloned embryos with 25 nM 5-aza-dC for 24 h significantly enhanced the blastocyst
rate compared with that of the untreated group. Furthermore, treating cloned embryos,
but not donor cells, significantly promoted pseudo-pronucleus formation at 4 h post
activation (51% for cloned embryos treated, 34% for donor cells treated and 36% for
control, respectively, P<0.05) and enhanced the expression levels of pluripotent
genes (Oct4, Nanog and Sox2) up to
those of in vitro fertilized embryos during embryo development. In
conclusion, treating cloned embryos, but not donor cells, with 5-aza-dC enhanced the
developmental competence of porcine cloned embryos by promotion of pseudo-pronucleus
formation and improvement of pluripotent gene expression. 相似文献
9.
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
10.
Seong Bin Park Kyoung Kwon In Seok Cha Ho Bin Jang Seong Won Nho Fernand F. Fagutao Young Kyu Kim Jong Earn Yu Tae Sung Jung 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):163-166
A multiplex PCR protocol was established to simultaneously detect major bacterial pathogens in olive flounder (Paralichthys olivaceus) including Edwardsiella (E.) tarda, Streptococcus (S.) parauberis, and S. iniae. The PCR assay was able to detect 0.01 ng of E. tarda, 0.1 ng of S. parauberis, and 1 ng of S. iniae genomic DNA. Furthermore, this technique was found to have high specificity when tested with related bacterial species. This method represents a cheaper, faster, and reliable alternative for identifying major bacterial pathogens in olive flounder, the most important farmed fish in Korea. 相似文献
11.
12.
Expression dynamics of bovine MX genes in the endometrium and placenta during
early to mid pregnancy
Takahiro SHIROZU Keisuke SASAKI Manabu KAWAHARA Yojiro YANAGAWA Masashi NAGANO Nobuhiko YAMAUCHI Masashi TAKAHASHI 《The Journal of reproduction and development》2016,62(1):29-35
MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has
antiviral activity. MX has at least two isoforms, known as MX1 and
MX2, in mammals. Moreover, bovine MX1 has been found to have alternative
splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is
temporarily produced from the conceptus before implantation and induces MX expression in the
endometrium. However, the expression dynamics of MX after implantation are not clear. In the
present study, we investigated the expression of MX1-a, MX1B and
MX2 in the endometrium and placenta before and after implantation along with the expression
of IFN-α, type I receptors (IFNAR1 and IFNAR2) and
interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were
divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples
were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P).
Although all the MX expressions were significantly higher in the IC and C at days 14–18,
presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C
and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC.
RT-PCR indicated IFNAR1, IFNAR2, IRF3 and
IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the
MX genes are affected by the type I IFN pathway during pregnancy and are involved in an
immune response to protect the mother and fetus. 相似文献
13.
Melissa A. Miller Barbara A. Byrne Spencer S. Jang Erin M. Dodd Elene Dorfmeier Michael D. Harris Jack Ames David Paradies Karen Worcester David A. Jessup Woutrina A. Miller 《Veterinary research》2010,41(1)
Although protected for nearly a century, California’s sea otters have been slow to recover, in part due to exposure to fecally-associated protozoal pathogens like Toxoplasma gondii and Sarcocystis neurona. However, potential impacts from exposure to fecal bacteria have not been systematically explored. Using selective media, we examined feces from live and dead sea otters from California for specific enteric bacterial pathogens (Campylobacter, Salmonella, Clostridium perfringens, C. difficile and Escherichia coli O157:H7), and pathogens endemic to the marine environment (Vibrio cholerae, V. parahaemolyticus and Plesiomonas shigelloides). We evaluated statistical associations between detection of these pathogens in otter feces and demographic or environmental risk factors for otter exposure, and found that dead otters were more likely to test positive for C. perfringens, Campylobacter and V. parahaemolyticus than were live otters. Otters from more urbanized coastlines and areas with high freshwater runoff (near outflows of rivers or streams) were more likely to test positive for one or more of these bacterial pathogens. Other risk factors for bacterial detection in otters included male gender and fecal samples collected during the rainy season when surface runoff is maximal. Similar risk factors were reported in prior studies of pathogen exposure for California otters and their invertebrate prey, suggesting that land-sea transfer and/or facilitation of pathogen survival in degraded coastal marine habitat may be impacting sea otter recovery. Because otters and humans share many of the same foods, our findings may also have implications for human health. 相似文献
14.
Talah Kanbar Andrey V. Voytenko J?rg Alber Christoph L?mmler Reinhard Weiss Vladimir N. Skvortzov 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):327-329
In the present study, Staphylococcus (S.) hyicus strains isolated in Russia (n = 23) and Germany (n = 17) were investigated for the prevalence of the previously described genes sheta and shetb. Sheta was detected in 16 S. hyicus strains. Sheta-positive strains were mainly found among strains isolated from exudative epidermitis, and frequently together with the exfoliative toxin-encoding genes exhD and exhC. Partial sequencing of sheta in a single S. hyicus strain revealed an almost complete match with the sheta sequence obtained from GenBank. None of the S. hyicus strains displayed a positive reaction with the shetb-specific oligonucleotide primer used in the present study. According to the present results, the exotoxin encoding gene sheta seems to be distributed among S. hyicus strains in Russia and Germany. The toxigenic potential of this exotoxin, which does not have the classical structure of a staphylococcal exfoliative toxin, remains to be elucidated. 相似文献
15.
R.C. Andrew Thompson Doug D. Colwell Todd Shury Amber J. Appelbee Carolyn Read Zablon Njiru Merle E. Olson 《Veterinary parasitology》2009
Coyotes from southern Alberta and Saskatchewan, Canada, were examined for the presence of Giardia and Cryptosporidium and cohabiting helminths. Toxascaris was present in over 90% of the 70 animals examined, and Taenia sp. in 6.5–25% of the two groups of animals studied. Giardia (12.5–21.7%) and Cryptosporidium (0–17.4%) were also common and molecular characterisation revealed both zoonotic and host-adapted genotypes of Giardia, whereas the Cryptosporidium proved to be a variant of the canine species C. canis. The seasonal variation observed in the occurrence of Cryptosporidium may be related to stress-induced shedding of the parasite. 相似文献
16.
Background
The mutant prevention concentration (MPC) is an important parameter to evaluate the likelihood of growth of fluoroquinolone-resistant mutants for antimicrobial-pathogen combinations. The MPCs of fluoroquinolones for different canine pathogens have not been compared. In this study, we compared for the first time orbifloxacin MPCs between susceptible strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus pseudintermedius of canine origin.Methods
More than 1010 CFU/ml of 10 strains of each bacterial species were inoculated onto Muller-Hinton agar supplemented with different concentrations of orbifloxacin from 1× to 64× minimum inhibitory concentration (MIC) and the MPCs were recorded. MICs of original strains and of mutants arising after exposure to sub-MPC concentrations (one per original strain) were determined in the presence or absence of efflux pump inhibitors (EPIs). The effects of quinolone resistance-determining region (QRDR) mutations were also examined.Results
MPCs were significantly higher for P. aeruginosa (16–128 μg/ml) than for E. coli (0.5–32 μg/ml). MPCs for S. pseudintermedius varied between the low-susceptible (16–128 μg/ml) and the high-susceptible strains (4–16 μg/ml) and were the most broadly distributed among the three species. Regarding resistance mechanisms, only one QRDR mutation in gyrA was found in all of the 10 mutants of E. coli and in 4 of the 10 mutants of P. aeruginosa, whereas mutations in both grlA and gyrA were found in 3 mutants and one mutation in grlA was found in 2 mutants among the 10 mutants of S. pseudintermedius. In the presence of an EPI, the MICs of P. aeruginosa mutants decreased markedly, those of E. coli mutants decreased moderately, and those of S. pseudintermedius mutants were unaffected.Conclusions
MPCs of orbifloxacin vary between bacterial species of canine pathogens, possibly due to the diversity of the main fluoroquinolone resistance mechanism among these species. Therefore, the type of bacterial species should be taken into consideration when using fluoroquinolone drugs such as orbifloxacin in canines. 相似文献17.
Khethiwe MTSHALI Zamantungwa T. H. KHUMALO Ryo NAKAO Dennis J. GRAB Chihiro SUGIMOTO Oriel M. M. THEKISOE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1573-1579
Ticks carry and transmit a remarkable array of pathogens including bacteria, protozoa and
viruses, which may be of veterinary and/or of medical significance. With little to no
information regarding the presence of tick-borne zoonotic pathogens or their known vectors
in southern Africa, the aim of our study was to screen for Anaplasma
phagocytophilum, Borrelia burgdorferi, Coxiella
burnetii, Rickettsia species and Ehrlichia
ruminantium in ticks collected and identified from ruminants in the Eastern
Cape, Free State, KwaZulu-Natal and Mpumalanga Provinces of South Africa. The most
abundant tick species identified in this study were Rhipicephalus evertsi
evertsi (40%), Rhipicephalus species (35%), Amblyomma
hebraeum (10%) and Rhipicephalus decoloratus (14%). A total of
1634 ticks were collected. DNA was extracted, and samples were subjected to PCR
amplification and sequencing. The overall infection rates of ticks with the target
pathogens in the four Provinces were as follows: A. phagocytophilum, 7%;
C. burnetii, 7%; E. ruminantium, 28%; and
Rickettsia spp., 27%. The presence of B. burgdorferi
could not be confirmed. The findings of this study show that zoonotic pathogens are
present in ticks in the studied South African provinces. This information will aid in the
epidemiology of tick-borne zoonotic diseases in the country as well as in raising
awareness about such diseases in the veterinary, medical and tourism sectors, as they may
be the most affected. 相似文献
18.
Philippe G.A.C. Vanden Bergh Laurent L.M. Zecchinon Thomas Fett Daniel Desmecht 《Veterinary research》2009,40(4)
Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, produces Apx toxins that are recognized as major virulence factors. Recently, we showed that ApxIIIA-cytotoxic activity specifically targets Sus scrofa leukocytes. Since both LtxA from Aggregatibacter actinomycetemcomitans (aggressive periodontitis in humans) and LktA from Mannheimia haemolytica (pneumonia in ruminants) share this characteristic, respectively towards human and ruminant leukocytes, and because both use the CD18 subunit to interact with their respective LFA-1, we hypothesized that ApxIIIA was likely to bind porcine CD18 to exercise its deleterious effects on pig leukocytes. A β
2−integrin-deficient ApxIIIA-resistant human erythroleukemic cell line was transfected either with homologous or heterologous CD11a/CD18 heterodimers using a set of plasmids coding for human (ApxIIIA-resistant), bovine (-resistant) and porcine (-susceptible) CD11a and CD18 subunits. Cell preparations that switched from ApxIIIA-resistance to -susceptibility were then sought to identify the LFA-1 subunit involved. The results showed that the ApxIIIA-resistant recipient cell line was rendered susceptible only if the CD18 partner within the LFA-1 heterodimer was that of the pig. It is concluded that porcine CD18 is necessary to mediate A. pleuropneumoniae ApxIIIA toxin-induced leukolysis. 相似文献
19.
Anselme SHYAKA Akiko KUSUMOTO Warangkhana CHAISOWWONG Yoshiki OKOUCHI Shinya FUKUMOTO Aya YOSHIMURA Keiko KAWAMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):967-972
The prevalence of Campylobacter jejuni in wild birds is a potential hazard for human and animal health. The aim of this study was to establish the prevalence of C. jejuni in wild birds in Tokachi area, Hokkaido, Japan and investigate their virulence in vitro. In total, 173 cloacal swabs from individual wild birds were collected for the detection of Campylobacter spp. Thirty four samples (19.7%) were positive for Campylobacter of which 94.1% (32/34 samples) were C. jejuni. Additionally, one C. coli and one C. fetus were isolated. Seven C. jejuni isolates (one from crows and the other from pigeons) had important virulence genes including all three CDT genes (cdtA, cdtB and cdtC) and flaA, flaB, ciaB and cadF,
and the other isolates were lacking cdtA gene. Further studies on in vitro virulence-associated phenotypes, such as motility assay on soft agar and invasion assay in Caco-2 cells, were performed. The wild bird C. jejuni isolates adhered and invaded human cells. Although the numbers of viable intracellular bacteria of wild bird isolates were lower than a type strain NCTC11168, they persisted at 48-hr and underwent replication in host cells. 相似文献
20.
Mitsuhiro KAMEYAMA Kiyoshi TOMINAGA Junko YABATA Yasuharu NOMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1437-1441
Patterns of insertion sequence (IS)629, norV
genotype, and Shiga toxin (Stx) genotype distribution were investigated amongst 203
enterohemorrhagic Escherichia coli O157 isolates collected in Yamaguchi
Prefecture, Japan, between 2004 and 2013. A total of 114 IS629 patterns
were identified; these were divided into eight IS groups (A–H). Ninety isolates carried an
intact norV gene, whereas 113 isolates carried a norV
with a 204-bp deletion. Other than one isolate from IS group G, all isolates with an
intact norV belonged to groups A–F, whereas isolates with a mutant
norV belonged to IS groups G and H. Seven stx
genotypes were identified, and of those, stx1a/stx2a was
predominant (n=105), followed by stx2c (n=32) and stx2a
(n=27). The stx1a/stx2a genotype was associated with the
mutant norV isolates, whereas isolates with an intact
norV had the stx2c genotype. Therefore, certain
combinations of IS type and stx genotype appear to be more frequent among
O157 clades which may be useful for detection of predominant subtypes in the interest of
public health. 相似文献