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1.
Background

Two deep-sea eels collected from the Western Pacific Ocean are described in this study. Based on their morphological characteristics, the two deep-sea eel specimens were assumed to belong to the cusk-eel family Ophidiidae and the cutthroat eel family Synaphobranchidae.

Methods and results

To accurately identify the species of the deep-sea eel specimens, we sequenced the mitochondrial genes (cytochrome c oxidase subunit I [COI] and 16S ribosomal RNA [16S rRNA]). Through molecular phylogenetic analysis based on mtDNA COI and 16S rRNA gene sequences, these species clustered with the genera Bassozetus and Synaphobranchus, suggesting that the deep-sea eel specimens collected are two species from the genera Bassozetus and Synaphobranchus in the Western Pacific Ocean, respectively.

Conclusions

This is the first study to report new records of the genera Bassozetus and Synaphobranchus from the Western Pacific Ocean based on COI and 16S rRNA genes

  相似文献   
2.
Porous calcium phosphate ceramics are used in orthopedic and craniofacial applications to treat bone loss, or in dental applications to replace missing teeth. The implantation of these materials, however, does not induce stem cell differentiation, so suitable additional materials such as porous calcium phosphate discs are needed to influence physicochemical responses or structural changes. Rabbit adipose-derived stem cells (ADSC) and mouse osteoblastic cells (MC3T3-E1) were evaluated in vitro by the MTT assay, semi-quantitative RT-PCR, and immunoblotting using cells cultured in medium supplemented with extracts from bioceramics, including calcium metaphosphate (CMP), hydroxyapatite (HA) and collagen-grafted HA (HA-col). In vivo evaluation of the bone forming capacity of these bioceramics in rat models using femur defects and intramuscular implants for 12 weeks was performed. Histological analysis showed that newly formed stromal-rich tissues were observed in all the implanted regions and that the implants showed positive immunoreaction against type I collagen and alkaline phosphatase (ALP). The intramuscular implant region, in particular, showed strong positive immunoreactivity for both type I collagen and ALP, which was further confirmed by mRNA expression and immunoblotting results, indicating that each bioceramic material enhanced osteogenesis stimulation. These results support our hypothesis that smart bioceramics can induce osteoconduction and osteoinduction in vivo, although mature bone formation, including lacunae, osteocytes, and mineralization, was not prominent until 12 weeks after implantation.  相似文献   
3.
An exaggerated exercise pressor reflex (EPR) contributes to exercise intolerance and excessive sympathoexcitation in the chronic heart failure (CHF) state, which is prevented by exercise training (ExT) at an early stage in the development of CHF. We hypothesized that ExT has a beneficial effect on the exaggerated EPR by improving the dysfunction of muscle afferents in CHF. We recorded the discharge of mechanically sensitive (group III) and metabolically sensitive (group IV) afferents in response to static contraction, passive stretch, and hindlimb intra-arterial injection of capsaicin in sham+sedentary (Sed), sham+ExT, CHF+Sed, and CHF+ExT rats. Compared with sham+Sed rats, CHF+Sed rats exhibited greater responses of group III afferents to contraction and stretch, whereas the responses of group IV afferents to contraction and capsaicin were blunted. ExT prevented the sensitization of group III responses to contraction or stretch and partially prevented the blunted group IV responses to contraction or capsaicin in CHF rats. Furthermore, we investigated whether purinergic 2X (P2X) and transient receptor potential vanilloid 1 (TRPV1) receptors mediate the altered sensitivity of muscle afferents by ExT in CHF. We found that the upregulated P2X and downregulated TRPV1 receptors in L4/5 dorsal root ganglia of CHF rats were normalized by ExT. Hindlimb intra-arterial infusion of a P2X antagonist attenuated the group III response to contraction or stretch in CHF rats to a greater extent than in sham rats, which was normalized by ExT. These findings suggest that ExT improves the abnormal sensitization of muscle afferents in CHF at least, in part, via restoring the dysfunction of P2X and TRPV1 receptors.  相似文献   
4.
We analyzed the genetic relationships and molecular characteristics of 34 Bacillus anthracis isolates from soil and clinical samples in various regions of Korea and 17 related Bacillus species, using the amplified fragment length polymorphism (AFLP) and multilocus variable-number tandem repeat (MLVA) approaches. Triplicate AFLP profiles of these strains showed high reproducibility and identified 376 polymorphisms. AFLP phylogenetic analysis of B. anthracis isolates showed a high level of similarity, 0.93, and this monomorphic fragment profile proved to be useful to differentiate B. anthracis strains from other Bacillus species. The B. cereus group was separated from other Bacillus species at a level of similarity of 0.68. Among them, some B. cereus strains showed genetic interspersion with B. thuringiensis strains. The evolutionary pattern of nucleotide differences among B. anthracis strains with the eight MLVA markers showed nine MLVA types. Three MLVA types, M1 to M3, were pathogenic B. anthracis isolates and were assigned as new genotypes belonging to the A4 and B3 clusters, compared with 89 genotypes deduced from previous data. This indicates that differences in cluster prevalence and distribution may be influenced more by MLVA markers on two plasmids loci and human activity. Consequently, we suggest that the novel MLVA type may represent significant evidence for historic adaptation to environmental conditions of the Asian continent, particularly Korea. Therefore, MLVA techniques may be available for molecular monitoring on anthrax-release-related bioterrorism and further study is required for the continuous epidemiological study of variable anthrax collections.  相似文献   
5.
目的:通过检测气道反应性和M2受体功能,研究呼吸道合胞病毒(RSV)感染与哮喘发病的关系及机制。方法:34只豚鼠随机分为4组:Hep-2滴鼻+生理盐水雾化(Hep-2/NS,A)组,RSV滴鼻+生理盐水雾化(RSV/NS,B)组,Hep-2滴鼻+鸡卵蛋白(OVA)雾化(Hep-2/OVA,C)组和RSV滴鼻+OVA雾化(RSV/OVA,D)组,其中A和B纽各9只,C和D组各8只,以A组为对照组。21d通过电刺激迷走神经检测各组气道反应性和M2受体功能,行嗜酸性粒细胞计数以及病理学观察。结果:B组气道内压力(mmH2O)与A组无明显差异(P〉0.05),给予匹罗卡品,IP下降幅度高于A组,但差别无显著性(P〉0.05)。C组IP明显高于A且(P〈0.05),且给予匹罗卡品,IP下降幅度明显低于A组,差别有显著性(P〈0.05)。D组IP明显高于C组(P〈0.05),给予匹罗卡品后IP下降幅度明显低于C组(P〈0.05)。结论:RSV感染可促进过敏原引起的M2R功能障碍,从而促进AHR发生。  相似文献   
6.
研究了14种外源物质(化合物)对灵芝细胞生长和发酵合成多糖和β-葡聚糖的影响。结果表明,连翘水提物(3g/L)对灵芝细胞生长具有显著促进作用;薏苡仁酯(3g/L)对灵芝胞内多糖和β-葡聚糖的合成均具有促进作用;而桔梗水提物、硝酸铈铵、硝酸镨、茉莉酸甲酯和硝普钠对灵芝细胞生长和产物合成均具有抑制作用。进一步通过Box-Behnken试验设计和响应面法分析,建立了添加薏苡仁酯发酵产β-葡聚糖的二次多项式模型,经分析得到产β-葡聚糖的最优条件为:薏苡仁酯添加量10.5g/L、接种量16%、添加时间第88小时、发酵初始pH 7.00。在此条件下获得β-葡聚糖的产量可达(40.67±8.43)mg/L,与未添加薏苡仁酯的对照组相比,提高了41.86%;多糖产量为(0.99±0.21)g/L,与对照组相比,提高了31.99%。结果提示所得添加薏苡仁酯的优化条件可定向诱导灵芝β-葡聚糖的合成,同时也表明在灵芝液体发酵体系中添加薏苡仁酯发酵产多糖和β-葡聚糖具有一定的实用价值。  相似文献   
7.
The Y chromosome has recently been suggested to have an association with prostate cancer risk in human populations. Since this chromosome is haploid and lacks recombination over most of its length, haplotypes constructed from binary markers throughout the chromosome can be used for association studies. To assess the possible Y-chromosomal contribution to prostate cancer risk, we have therefore analyzed 14 Y-chromosomal binary markers in 106 prostate cancer cases and 110 controls from the Korean population. In contrast to previous findings in the Japanese population, no statistically significant difference in the distribution of Y-chromosomal haplogroup frequencies was observed between the case and control groups of Koreans. Thus, our data imply that the previously reported associations between Y-chromosomal lineages and a predisposition to, or protection against, prostate cancer might be explained by statistical fluctuations, or by genetic effects that are seen only in some environments.  相似文献   
8.
9.
We analyzed the genetic relationships and molecular characteristics of 34 Bacillus anthracis isolates from soil and clinical samples in various regions of Korea and 17 related Bacillus species, using the amplified fragment length polymorphism (AFLP) and multilocus variable-number tandem repeat (MLVA) approaches. Triplicate AFLP profiles of these strains showed high reproducibility and identified 376 polymorphisms. AFLP phylogenetic analysis of B. anthracis isolates showed a high level of similarity, 0.93, and this monomorphic fragment profile proved to be useful to differentiate B. anthracis strains from other Bacillus species. The B. cereus group was separated from other Bacillus species at a level of similarity of 0.68. Among them, some B. cereus strains showed genetic interspersion with B. thuringiensis strains. The evolutionary pattern of nucleotide differences among B. anthracis strains with the eight MLVA markers showed nine MLVA types. Three MLVA types, M1 to M3, were pathogenic B. anthracis isolates and were assigned as new genotypes belonging to the A4 and B3 clusters, compared with 89 genotypes deduced from previous data. This indicates that differences in cluster prevalence and distribution may be influenced more by MLVA markers on two plasmids loci and human activity. Consequently, we suggest that the novel MLVA type may represent significant evidence for historic adaptation to environmental conditions of the Asian continent, particularly Korea. Therefore, MLVA techniques may be available for molecular monitoring on anthrax-release-related bioterrorism and further study is required for the continuous epidemiological study of variable anthrax collections.  相似文献   
10.
Gao XY  Wang HJ  Zhang Y  Lu ZH  Wang W  Zhu GQ 《Life sciences》2006,78(10):1129-1134
A closed-loop implanted chip system was designed to control blood pressure without using drugs. The chip system instantaneously reset blood pressure by stimulating the left aortic depressor nerve according to the feedback signals of arterial blood pressure. The relationship between pressure signals and frequency of stimulation was identified in vitro and in vivo, and the efficiency of the chip system was evaluated in normal anesthetized Wistar rats. To determine whether the depressor effect of the chip was primarily independent on the bradycardia induced by the resetting, the effects of methyl atropine (1.5 g/kg, iv.) and bilateral vagotomy on depressor effect induced by the chip system were determined, respectively. The results indicated that the chip system worked well. The frequency of stimulus linearly increased following the elevation of pressure from 70 to 160 mm Hg. The frequency of the stimulus reached its maximum (100 Hz) when pressure exceeded 160 mm Hg, and the stimulation stopped when MAP was below 70 mm Hg. There were significant decreases in mean arterial pressure (MAP, -20.0+/-4.4 mm Hg) and heart rate (HR, -43.0+/-10.5 bpm) during the resetting in rats. After resetting, both MAP and HR recovered in a minute without any significant rebound. Pretreatment with either methyl atropine or bilateral vagotomy abolished the bradycardia effect but produced no significant effect on hypotension. The results demonstrated that the chip system successfully reset blood pressure in rats, and that the hypotension induced by the chip system was primarily independent on the bradycardia effect.  相似文献   
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