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111.
Twenty bacterial strains, grown on aniline as a sole source of carbon and nitrogen, and isolated from soil, were identified by morphological and biochemical tests, and cell wall analyses. Eight isolates were Rhodococcus erythropolis (Gray and Thornton) Goodfellow and Alderson, five were Pseudomonas maltophilia Hugh and Ryschenkow and seven were DAB (diaminobutyric acid)-type coryneform bacteria. The Rhodococcus spp. maintained the ability to assimilate aniline, but the pseudomonads and coryneform bacteria readily lost the ability, when grown in the absence of aniline.  相似文献   
112.
Transient receptor potential canonical channel (TRPC) is a nonselective cation channel permeable to Ca2+, which express in many cell types, including neurons. However the alterations in TRPC receptor expressions in response to status epilepticus (SE) have not been explored. Therefore, the present study was designated to elucidate the roles of TRPC3 in neuronal death and vasogenic edema within the rat piriform cortex (PC) following SE. In non-SE animals, TRPC3 immunoreactivity was abundantly detected in the PC. Following SE, TRPC3 immunoreactivity was increased in neurons. Furthermore, TRPC3 expression was detected in endothelial cells that did not contain it in non-SE animals. Loss of SMI-71 (a blood–brain barrier antigen) immunoreactivity was also observed in TRPC3 positive endothelial cells. In addition, FJB positive neurons and vasogenic edema were noticeably detected in the PC. To directly determine whether TRPC3 activation is correlated to SE-induced vasogenic edema formation and neuronal damages in the PC, the effect of Pyr-3 (a TRPC3 antagonist) on SE-induced insults were investigated. Pyr-3 infusion effectively attenuated vasogenic edema in the PC as compared to the vehicle. Therefore, our findings indicate that TRPC3 activation/overexpression induced by SE may involve BBB disruption and neuronal damages in the rat PC following SE. Therefore, the present study was TRPC3 may play an important role in SE-induced vasogenic edema formation through BBB disruptions in the rat PC.  相似文献   
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We screened a protoberberine backbone derivative library for compounds with anti-proliferative effects on p53-defective cancer cells. A compound identified from this small molecule library, cadein1 (cancer-selective death inducer 1), an isoquinolinium derivative, effectively leads to a G2/M delay and caspase-dependent apoptosis in various carcinoma cells with non- functional p53. The ability of cadein1 to induce apoptosis in p53-defective colon cancer cells was tightly linked to the presence of a functional DNA mismatch repair (MMR) system, which is an important determinant in chemosensitivity. Cadein1 was very effective in MMR+/p53 cells, whereas it was not effective in p53+ cells regardless of the MMR status. Consistently, when the function of MMR was blocked with short hairpin RNA in SW620 (MMR+/p53) cells, cadein1 was no longer effective in inducing apoptosis. Besides, the inhibition of p53 increased the pro-apoptotic effect of cadein1 in HEK293 (MMR+/p53+) cells, whereas it did not affect the response to cadein1 in RKO (MMR/p53+) cells. The apoptotic effects of cadein1 depended on the activation of p38 but not on the activation of Chk2 or other stress-activated kinases in p53-defective cells. Taken together, our results show that cadein1 may have a potential to be an anti-cancer chemotherapeutic agent that is preferentially effective on p53-mutant colon cancer cells with functional MMR.  相似文献   
115.
Using 16S rRNA gene sequencing analysis, we examined the bacterial diversity and the presence of opportunistic bacterial pathogens (i.e., Campylobacter and Helicobacter) in red knot (Calidris canutus; n = 40), ruddy turnstone (Arenaria interpres; n = 35), and semipalmated sandpiper (Calidris pusilla; n = 22) fecal samples collected during a migratory stopover in Delaware Bay. Additionally, we studied the occurrence of Campylobacter spp., enterococci, and waterfowl fecal source markers using quantitative PCR (qPCR) assays. Of 3,889 16S rRNA clone sequences analyzed, the bacterial community was mostly composed of Bacilli (63.5%), Fusobacteria (12.7%), Epsilonproteobacteria (6.5%), and Clostridia (5.8%). When epsilonproteobacterium-specific 23S rRNA gene clone libraries (i.e., 1,414 sequences) were analyzed, the sequences were identified as Campylobacter (82.3%) or Helicobacter (17.7%) spp. Specifically, 38.4%, 10.1%, and 26.0% of clone sequences were identified as C. lari (>99% sequence identity) in ruddy turnstone, red knot, and semipalmated sandpiper clone libraries, respectively. Other pathogenic species of Campylobacter, such as C. jejuni and C. coli, were not detected in excreta of any of the three bird species. Most Helicobacter-like sequences identified were closely related to H. pametensis (>99% sequence identity) and H. anseris (92% sequence identity). qPCR results showed that the occurrence and abundance of Campylobacter spp. was relatively high compared to those of fecal indicator bacteria, such as Enterococcus spp., E. faecalis, and Catellicoccus marimammalium. Overall, the results provide insights into the complexity of the shorebird gut microbial community and suggest that these migratory birds are important reservoirs of pathogenic Campylobacter species.  相似文献   
116.
M Kim  S Kim  S Ryu 《Journal of virology》2012,86(19):10894
Salmonella enterica serovar Typhimurium rough strain-specific phage SSU5 was isolated, and its whole genome was sequenced. The 103,229-bp-long double-stranded DNA genome of SSU5 encodes 130 open reading frames with one tRNA for asparagine. Genomic analysis revealed that SSU5 might be the phylogenetic origin of cryptic plasmid pHCM2 harbored by Salmonella Typhi CT18.  相似文献   
117.
Branching patterns of the trunk lateral line nerves were studied in 46 pleuronectiform species, representing nine families in two suborders. The dorsal fin longitudinal ramus (DFLR), derived from the main nerve (horizontal septum lateral line nerve), passed closely along the course of the middle trunk lateral line in all specimens examined, the dorsal longitudinal collector nerve (DLCN) partly coalescing with the DFLR along the arched part of the lateral line in Psettodes erumei (Psettodoidei), compared with the entire length of the latter in all other species (Pleuronectoidei). Citharidae, Paralichthyidae, and Pleuronectidae were characterized by having a simple, elongated dorsal ramule; Bothidae was unique in having more than one dorsal ramule, forming a ladder-like network and peripherally giving off numerous minute branches; Poecilopsettidae and Samaridae possessed a few, short dorsal ramules; Soleidae and Cynoglossidae were characteristic in having a dendritic dorsal ramule. Secondary modifications of the course of the middle trunk lateral line were detected by nerve information, the arched part of the lateral line having been secondarily highly elevated in some genera of Pleuronectidae, but secondarily straightened in Samaridae.  相似文献   
118.

Background  

Pichia pastoris has been recognized as an effective host for recombinant protein production. A number of studies have been reported for improving this expression system. However, its physiology and cellular metabolism still remained largely uncharacterized. Thus, it is highly desirable to establish a systems biotechnological framework, in which a comprehensive in silico model of P. pastoris can be employed together with high throughput experimental data analysis, for better understanding of the methylotrophic yeast's metabolism.  相似文献   
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A series of 2-thio pyridine C-region analogues of 2-(3-fluoro-4-methylsulfonylaminophenyl)propanamides were investigated as hTRPV1 antagonists. Among them, compound 24S showed stereospecific and excellent TRPV1 antagonism of capsaicin-induced activation. Further, it demonstrated strong anti-allodynic in a rat neuropathic pain model. Consistent with its action in vitro being through TRPV1, compound 24S blocked capsaicin-induced hypothermia in mice. Docking analysis of 24S with our hTRPV1 homology model was performed to identify its binding mode.  相似文献   
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