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91.
Erol OO 《Plastic and reconstructive surgery》2005,115(1):358-360
92.
Anguita J Samanta S Ananthanarayanan SK Revilla B Geba GP Barthold SW Fikrig E 《FEMS immunology and medical microbiology》2002,34(3):187-191
Cyclooxygenase (Cox) is a key enzyme in the biosynthetic metabolism of prostaglandins. The inducible isoform of Cox-2 has been implicated in inflammation and its specific inhibition can be used to treat noninfectious inflammatory diseases, such as rheumatoid arthritis. Borrelia burgdorferi, the agent of Lyme disease, can induce joint inflammation. Here we show that B. burgdorferi induced the upregulation of cox-2 gene expression in murine joints at the onset of arthritis in infected mice. The level of mRNA expression correlated with the degree of inflammation. The specific inhibition of Cox-2 diminished the degree of joint inflammation, without affecting B. burgdorferi-specific antibody or cytokine responses. Cox-2 activity is therefore associated with the genesis of infectious arthritis caused by B. burgdorferi. 相似文献
93.
94.
Ebru Ince Yilmaz Murat Yavuz Murat Kizil 《World journal of microbiology & biotechnology》2008,24(8):1461-1470
As part of a research program whose aim is to determine the diversity of streptomycetes in order to discover new bioactive
secondary metabolites, rhizosphere soils of three indigenous plants were analyzed. A total of 55 actinomycetes were isolated
using three different medium from the samples. The rhizospheric soil of the plant Aethionema dumanii gave the highest number of actinomycetes, i.e., 42% versus 27% and 31% for the soils from Salvia aytachii and Achillea ketenoglui, respectively. The AIA is the most favorable medium for the isolation of the actinomycetes from different rhizospheric soils.
16S rDNA sequence analysis revealed that while some isolates belong to different cluster groups such as Streptomyces lydicus, S. rochei, S. microflavus, S. griseoflavus, S. albidoflavus and S. violaceusniger, the majority of the sequences did not considerable clustered with the member of different Streptomyces groups. The in vitro antimicrobial activities of the crude organic and aqueous extracts of isolates were screened using a
disc diffusion assay against a panel of bacteria and C. albicans. A total of 22 isolates showed antimicrobial activity. The antibacterial action of the extracts is more pronounced on Gram-positive
than on Gram-negative bacteria in most cases. About 18% of the actinomycetes showed also antifungal activity. Study of the
influence of two different culture media on production of bioactive molecules showed that the higher antimicrobial activity
was obtained in M2 when compared to TSB. The results from this study provide evidence that the streptomycetes in the rhizosphere
soils could be promising sources for antimicrobial bioactive agents. 相似文献
95.
96.
Tick-host-pathogen interactions in Lyme borreliosis 总被引:1,自引:0,他引:1
Borrelia burgdorferi, the spirochetal agent of Lyme borreliosis, is predominantly transmitted by Ixodes ticks. Spirochetes have developed many strategies to adapt to the different environments that are present in the arthropod vector and the vertebrate host. This review focuses on B. burgdorferi genes that are preferentially expressed in the tick and the vertebrate host, and describes how selected gene products facilitate spirochete survival throughout the enzootic life cycle. Interestingly, B. burgdorferi also enhances expression of specific Ixodes scapularis genes, such as TROSPA and salp15. The importance of these genes and their products for B. burgdorferi survival within the tick, and during the transmission process, will also be reviewed. Moreover, we discuss how such vector molecules could be used to develop vector-antigen-based vaccines to prevent the transmission of B. burgdorferi and, potentially, other arthropod-borne microbes. 相似文献
97.
HERG CCardiac, a C-terminal splice variant of the human ether-à-go-go-related gene (HERG A), was identified and found to be 100% homologous
to HERGUSO. Real-time polymerase chain reaction data indicated that in the human heart HERG CCardiac mRNA was expressed eight times more than HERG A, whereas in human ventricular tissue it was expressed six times more than
HERG A. A HERG CCardiac-green fluorescence protein (GFP) construct was heterologously expressed in Xenopus oocytes. Confocal micrographs revealed that HERG CCardiac was mainly expressed in the plasma membrane. HERG CCardiac channel expressed in oocytes produced slower inactivating outward currents and faster deactivating tail currents than those
of HERG A channel. Equal amounts of HERG A and HERG CCardiac cRNA coinjected into oocytes formed intermediate HERG A + HERG CCardiac heteromultimers, which was reconfirmed by immunoprecipitation experiments with a HERG A N-terminal antibody. These heteromultimers
had different inactivation, deactivation and activation kinetics from those of HERG A and HERG CCardiac channels. HERG A + HERG CCardiac heteromultimers significantly reduced the model action potential mean amplitude and increased the fast and slow inactivation
τ values of the action potential repolarization phase, suggesting involvement of HERG A and HERG CCardiac heteromultimers in modulation of the refractory interval. 相似文献
98.
Bal R Türk G Yılmaz Ö Etem E Kuloğlu T Baydaş G Naziroğlu M 《Cell biology and toxicology》2012,28(3):187-200
Clothianidin (CTD) is one of the latest members of the synthetic organic insecticides, the neonicotinoids. In the present
study, it was aimed to investigate if daily oral administration of CTD at low doses for 90 days has any deleterious effects
on reproductive functions of developing male rats. Animals were randomly divided into four groups of six rats each, assigned
as control rats, or rats treated with 2 (CTD-2), 8 (CTD-8) or 32 (CTD-32) mg CTD/kg body weight by oral gavage. The significant
decreases of the absolute weights of right cauda epididymis and seminal vesicles, and body weight were detected in the animals
exposed to CTD administration at 32 mg/kgBW/day. Epididymal sperm concentration decreased significantly in CTD-32 group and
the abnormal sperm rates increased in CTD-8 and CTD-32 groups when compared to control group. The testosterone level was significantly
decreased in CTD-32 group when compared to control group. The administration of all CTD doses resulted in a significant decrease
in the level of GSH. The number of TUNEL-positive cells significantly increased in the germinal epithelium of testis of rats
exposed to CTD at 32 mg/kgBW/day. In groups CTD-8 and CTD-32, only docosapentaenoic, arachidonic, palmitic and palmitoleic
acids were significantly elevated when compared to control. The ratios of 20:4/18:2 and 18:1n−9/18:0 were decreased when rats exposed to CTD. Sperm DNA fragmentation was observed in CTD-32 group, but not CTD-2 and CTD-8.
It is concluded that low doses of CTD exposure during critical stages of sexual maturation had moderate detrimental effects
on reproductive organ system and more severe effects are likely to be observed at higher dose levels. In addition, the reproductive
system may be more sensitive to exposure of CTD even earlier in development (prenatal and early postnatal), and therefore
it could be expected that more severe effects could also be observed at the NOAEL dose levels, if dosing had occurred in utero
or early postnatal. 相似文献
99.
Methicillin resistance in staphylococci is primarily due to the presence of a mecA gene which encodes the novel penicillin binding protein2a. Some chromosomal factors such as femA and femB also participate in the expression of methicillin resistance. This study was designed to detect methicillin resistance by cefoxitin disk diffusion and penicillin binding protein2a latex agglutination methods, and to compare mecA, femA, femB and femX gene positivities. A total of 60 MRSA isolates were included in the evaluation. PCR analysis showed that all isolates were positive for mecA and femA genes. Seven of these isolates tested negative by the latex agglutination test. Fifteen isolates were positive for femB and 28 isolates for femX gene. This study implicated that for the determination of methicillin resistance, latex agglutination test is the least reliable method when compared to PCR and cefoxitin disk diffusion test. femA gene shows more correlation than femB and femX with methicillin resistance. 相似文献
100.