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101.
Dwarf bamboo species are monocarpic. They flower simultaneously and die after several decades. The type of flowering in the
genus Sasa ranges from sporadic to gregarious. In order to determine whether or not the sporadic flowering of dwarf bamboo is fixed
genetically, we investigated the distribution of clones using eight microsatellite (SSR) loci in a sporadic flowering patch
of Sasa cernua Makino, a major dwarf bamboo species found in central Hokkaido. In May 2006, flowering occurred on 60.5% of living culms
in a 1600 m2 patch. We established a 50 × 10 m study plot in this patch and noted 1267 clumps consisting of 2529 living culms. We investigated
all 1267 clumps and identified six multilocus genotypes as clones using five variable SSR loci. All flowering clumps belonged
to the same clone. On the other hand, non-flowering vegetative clumps were also discovered to be of the same clone. These
data suggest that all flowering culms originated from a single clone of a sporadic flowering patch of S. cernua. Clonal analysis for investigation of sporadic flowering of S. cernua revealed that only a portion of a clone flowers and dies instead of the whole clone. 相似文献
102.
Takashi Kawahara Hiroki Ito Hideyuki Terao Yoshitake Kato Hiroji Uemura Yoshinobu Kubota Junichi Matsuzaki 《PloS one》2012,7(12)
Objective
To determine the impact of ureteroscopy-assisted retrograde nephrostomy (UARN) during percutaneous nephrolithotomy (PCNL).Materials and Methods
From April 2009 to September 2011, a total of 50 patients underwent PCNL for large renal stones (stone burden >2 cm). We performed UARN in the Galdakao-modified Valdivia position for 27 patients (UARN PCNL) and ultrasonography-assisted percutaneous nephrostomy in the prone position for 23 patients (prone PCNL).Results
UARN PCNL significantly improved the stone-free rate (81.5% vs 52.2%) and the rate of residual stones (<4 mm, 92.6% vs 65.2%, P<0.05). The median length of the operation was significantly shorter for UARN PCNL, at 160 min, compared to 299 min for prone PCNL (P<0.001). There was one intraoperative complication in prone PCNL, namely a hemorrhage that resulted in stopping the initial treatment, but it was cured conservatively. The postoperative complications included a high grade fever that persisted for three days in two UARN PCNL patients (7.4%) and six prone PCNL patients (26.1%). The Clavien grading scores showed significantly lower postoperative complications for UARN PCNL compared to prone PCNL.Conclusion
UARN is associated with a higher stone-free rate, shorter operation time, and fewer complications during PCNL than prone PCNL. 相似文献103.
Analysis of simian immunodeficiency virus sequence variation in tissues of rhesus macaques with simian AIDS. 总被引:3,自引:17,他引:3 下载免费PDF全文
One rhesus macaque displayed severe encephalomyelitis and another displayed severe enterocolitis following infection with molecularly cloned simian immunodeficiency virus (SIV) strain SIVmac239. Little or no free anti-SIV antibody developed in these two macaques, and they died relatively quickly (4 to 6 months) after infection. Manifestation of the tissue-specific disease in these macaques was associated with the emergence of variants with high replicative capacity for macrophages and primary infection of tissue macrophages. The nature of sequence variation in the central region (vif, vpr, and vpx), the env gene, and the nef long terminal repeat (LTR) region in brain, colon, and other tissues was examined to see whether specific genetic changes were associated with SIV replication in brain or gut. Sequence analysis revealed strong conservation of the intergenic central region, nef, and the LTR. However, analysis of env sequences in these two macaques and one other revealed significant, interesting patterns of sequence variation. (i) Changes in env that were found previously to contribute to the replicative ability of SIVmac for macrophages in culture were present in the tissues of these animals. (ii) The greatest variability was located in the regions between V1 and V2 and from "V3" through C3 in gp120, which are different in location from the variable regions observed previously in animals with strong antibody responses and long-term persistent infection. (iii) The predominant sequence change of D-->N at position 385 in C3 is most surprising, since this change in both SIV and human immunodeficiency virus type 1 has been associated with dramatically diminished affinity for CD4 and replication in vitro. (iv) The nature of sequence changes at some positions (146, 178, 345, 385, and "V3") suggests that viral replication in brain and gut may be facilitated by specific sequence changes in env in addition to those that impart a general ability to replicate well in macrophages. These results demonstrate that complex selective pressures, including immune responses and varying cell and tissue specificity, can influence the nature of sequence changes in env. 相似文献
104.
Kubota M Kawahara K Sekiya K Uchida T Hattori Y Futamata H Hiraishi A 《Systematic and applied microbiology》2005,28(2):165-174
Seven strains of dibenzofuran (DF)-degrading bacteria isolated from dioxin-polluted environments were characterized. These isolates were able to grow with dibenzofuran as the sole carbon and energy source. During the growth with dibenzofuran, they produced a soluble yellow metabolite that exhibited a unique pH-dependent shift of absorption maxima. Dibenzo-p-dioxin and biphenyl were also degraded with pigment production. The isolates were strictly aerobic and chemoorganotrophic and had gram-positive, nonmotile, rod-shaped cells. Chemotaxonomic analyses showed that cells contained L,L-diaminopimeric acid in the peptidoglycan, branched-chain fatty acids as major fatty acids, and menaquinone MK-8(H4) as the sole respiratory quinone. The G + C content of the DNA of the isolates ranged from 72.0 to 72.4 mol%. The 16S rRNA gene sequences of the isolates were very similar to each other (> or = 99.8%). The phylogenetic analysis showed that the isolates formed a cluster with species of the genus Nocardioides with Nocardioides simplex and Nocardioides nitrophenolicus as their nearest neighbors. DNA-DNA hybridization studies showed that the isolates showed a hybridization level of less than 55% to any tested species of the genus Nocardioides. Based on these data, Nocardioides aromaticivorans sp. nov. is proposed for the new DF-degrading isolates. The type strain is strain H-1 (IAM 14992, JCM 11674, DSM 15131). 相似文献
105.
Osamu Ichii Saori Otsuka-Kanazawa Taro Horino Junpei Kimura Teppei Nakamura Manabu Matsumoto Makoto Toi Yasuhiro Kon 《PloS one》2014,9(10)
MicroRNAs contribute to the pathogenesis of certain diseases and may serve as biomarkers. We analyzed glomerular microRNA expression in B6.MRLc1, which serve as a mouse model of autoimmune glomerulonephritis. We found that miR-26a was the most abundantly expressed microRNA in the glomerulus of normal C57BL/6 and that its glomerular expression in B6.MRLc1 was significantly lower than that in C57BL/6. In mouse kidneys, podocytes mainly expressed miR-26a, and glomerular miR-26a expression in B6.MRLc1 mice correlated negatively with the urinary albumin levels and podocyte-specific gene expression. Puromycin-induced injury of immortalized mouse podocytes decreased miR-26a expression, perturbed the actin cytoskeleton, and increased the release of exosomes containing miR-26a. Although miR-26a expression increased with differentiation of immortalized mouse podocytes, silencing miR-26a decreased the expression of genes associated with the podocyte differentiation and formation of the cytoskeleton. In particular, the levels of vimentin and actin significantly decreased. In patients with lupus nephritis and IgA nephropathy, glomerular miR-26a levels were significantly lower than those of healthy controls. In B6.MRLc1 and patients with lupus nephritis, miR-26a levels in urinary exosomes were significantly higher compared with those for the respective healthy control. These data indicate that miR-26a regulates podocyte differentiation and cytoskeletal integrity, and its altered levels in glomerulus and urine may serve as a marker of injured podocytes in autoimmune glomerulonephritis. 相似文献
106.
Cypripedium macranthos var. rebunense is an endangered plant endemic to Rebun Island, Japan. A proper understanding of genetic diversity is needed when conducting
conservation programs for rare and endangered species. We therefore examined the genetic diversity of C. macranthos var. rebunense using allozyme markers with a view to future conservation. Our study revealed that C. macranthos var. rebunense has relatively high genetic diversity (P was 0.62, n
a and n
e were 1.85 and 1.28 respectively, and H
o and H
e were 0.163 and 0.187, respectively) when compared with other plant taxa. The natural habitats of C. macranthos var. rebunense are geographically separated into northern and the southern populations. Disappearance of alleles and increase in homozygosity
expected as a result of the bottleneck effect were observed, particularly in the southern populations composed of a small
number of plants. As additional negative effects (inbreeding depression and further genetic drift) due to fragmentation are
predicted in these populations, the southern populations may show deterioration of genetic diversity in the near future. 相似文献
107.
108.
The methanol extract of Sophora flavescens, which is used in traditional Chinese medicine (sophorae radix), showed potent Na(+)-glucose cotransporter (SGLT) inhibitory activity. Our search for active components identified many well-known flavonoid antioxidants: kurarinone, sophoraflavanone G, kushenol K, and kushenol N. 相似文献
109.
Makoto Yamanaka Shigeki Nakamura Aiko Inoue Takashi Yasuda Yuichi Inoue Hiroharu Kawahara 《Cytotechnology》2010,62(4):287-291
Sodium butyrate (NaB) induced the membrane enclosed cell size vesicles from several IgM producing cell lines. We considered
the application of the cell-derived vesicles (CDVs) to drug delivery system (DDS) using the lung cancer specific IgM producing
AE6 cell line. Microscopic observation showed that the DiI fluorescence labeled AE6 vesicles were incorporated into the lung
cancer cell line A549. The anticancer drug, actinomycin D (actD), contained in AE6 and Ramos vesicles decreased the A549 cell
viability to 46 and 62% of control without actD, respectively. The cytotoxic effect in AE6 vesicles was superior to that in
the Ramos vesicles that have the lung cancer non-specific IgM on their surfaces. However, the result of the Ramos vesicles
suggests that the surface molecules other than IgM may interact with the A549 cells. In our method for vesicle production,
more specific and abundant antibodies mounted vesicles can be generated by transfection of their genes into cells followed
by NaB treatment. These suggest that the CDVs may be useful for the development of a drug carrier for DDS. 相似文献
110.