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111.
K. Samuel D. Debashish B. Madhumita G. Padmaja Siva Ram Prasad V. Bhaskara Ramana Murthy P. S. Rao 《In vitro cellular & developmental biology. Plant》2009,45(4):466-473
The propagation of Givotia rottleriformis Griff. is difficult as a result of long seed dormancy associated with poor seed germination. The present study was undertaken
to develop a protocol to overcome seed dormancy by culture of zygotic embryo axes and then develop an efficient method for
micropropagation of Givotia. Best germination frequency (78.3%) was achieved from mature zygotic embryo axes isolated from acid-scarified fresh seeds
when cultured on Murashige and Skoog (MS) medium (half-strength major salts) with 28.9 μM gibberellic acid (GA3). Efficient plant conversion was achieved by transfer of 10-d-old germinated embryos to MS medium (half-strength major salts)
supplemented with 1.2 μM kinetin (KN) and 0.5 μM indole-3-butyric acid (IBA). However, acid scarification of 1-yr-old seeds
decreased the germination frequency of zygotic embryo axes in comparison to those obtained from non-acid-scarified seeds which
germinated (96.2%) and converted into plants (80.3%) on MS basal (half-strength major salts) medium. Multiple shoot bud induction
was achieved by culture of shoot tips derived from in vitro germinated seedlings on MS medium with 0.5 μM thidiazuron for 4 wk, and the shoots elongated after transfer to a secondary
medium with 1.2 μM KN. A maximum number of 7.8 shoots per explant with an average shoot length of 3.2 cm was achieved after
two subcultures on this medium. The in vitro regenerated shoots rooted (41.5%) on half-strength MS medium with 0.5 μM IBA. The in vitro generated seedlings and micropropagated plants were established in soil with a survival frequency of 70% and 60%, respectively. 相似文献
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So Kato Yasushi Oshima Hiroyuki Oka Hirotaka Chikuda Yujiro Takeshita Kota Miyoshi Naohiro Kawamura Kazuhiro Masuda Junichi Kunogi Rentaro Okazaki Seiichi Azuma Nobuhiro Hara Sakae Tanaka Katsushi Takeshita 《PloS one》2015,10(4)
Objectives
The Japanese Orthopaedic Association (JOA) score is widely used to assess the severity of clinical symptoms in patients with cervical compressive myelopathy, particularly in East Asian countries. In contrast, modified versions of the JOA score are currently accepted as the standard tool for assessment in Western countries. The objective of the present study is to compare these scales and clarify their differences and interchangeability and verify their validity by comparing them to other outcome measures.Materials and Methods
Five institutions participated in this prospective multicenter observational study. The JOA and modified JOA (mJOA) proposed by Benzel were recorded preoperatively and at three months postoperatively in patients with cervical compressive myelopathy who underwent decompression surgery. Patient reported outcome (PRO) measures, including Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), the Short Form-12 (SF-12) and the Neck Disability Index (NDI), were also recorded. The preoperative JOA score and mJOA score were compared to each other and the PRO values. A Bland-Altman analysis was performed to investigate their limits of agreement.Results
A total of ninety-two patients were included. The correlation coefficient (Spearman’s rho) between the JOA and mJOA was 0.87. In contrast, the correlations between JOA/mJOA and the other PRO values were moderate (|rho| = 0.03 – 0.51). The correlation coefficient of the recovery rate between the JOA and mJOA was 0.75. The Bland-Altman analyses showed that limits of agreement were 3.6 to -1.2 for the total score, and 55.1% to -68.8% for the recovery rates.Conclusions
In the present study, the JOA score and the mJOA score showed good correlation with each other in terms of their total scores and recovery rates. Previous studies using the JOA can be interpreted based on the mJOA; however it is not ideal to use them interchangeably. The validity of both scores was demonstrated by comparing these values to the PRO values. 相似文献115.
Background
The G-protein-coupled receptors (GPCRs) constitute one of the largest and most ancient superfamilies of membrane proteins. They play a central role in physiological processes affecting almost all aspects of the life cycle of an organism. Availability of the complete sets of putative members of a family from diverse species provides the basis for cross genome comparative studies. 相似文献116.
Cells are inherently robust to environmental perturbations and have evolved to recover readily from short-term exposure to heat, pH changes, and nutrient deprivation during times of stress. The stress of unfolded protein accumulation has been implicated previously in low protein yields during heterologous protein expression. Here we describe the dynamics of the response to this stress, termed the unfolded protein response (UPR), during the expression of the single chain antibody 4-4-20 (scFv) in Saccharomyces cerevisiae. Expression of scFv decreased the growth rate of yeast cells whether the scFv was expressed from single-copy plasmids or integrated into the chromosome. However, the growth rates recovered at longer expression times, and surprisingly, the recovery occurred more quickly in the high-copy integration strains. The presence of a functional UPR pathway was necessary for a recovery of normal growth rates. During the growth inhibition, the UPR pathway appeared to be activated, resulting in decreased intracellular scFv levels and intermittent recovery of the chaperone BiP within the endoplasmic reticulum. Intracellular scFv was observed primarily in the endoplasmic reticulum, consistent with activation of the UPR pathway. Although the intracellular scFv levels dropped over the course of the expression, this was not a result of scFv secretion. A functional UPR pathway was necessary for the drop in intracellular scFv, suggesting that the decrease was a direct response of UPR activation. Taken together, these results suggest that control of heterologous gene expression to avoid UPR activation will result in higher production levels. 相似文献
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LIM Mineralization Protein-1 (LMP-1) has been cloned and shown to be osteoinductive. Our efforts to understand the mode of action of LMP-1 led to the determination that LMP-1 interacts with Smad Ubiquitin Regulatory Factor-1 (Smurf1). Smurf1 targets osteogenic Smads, Smad1/5, for ubiquitin-mediated proteasomal degradation. Smurf1 interaction with LMP-1 or Smads is based on the presence of unique WW-domain interacting motif in these target molecules. By performing site-directed mutagenesis and binding studies in vitro on purified recombinant proteins, we identified a specific motif within the osteogenic region of several LMP isoforms that is necessary for Smurf1 interaction. Similarly, we have identified that the WW2 domain of Smurf1 is necessary for target protein interaction. Here, we present a homology-based modeling of the Smurf1 WW2 domain and its interacting motif of LMP-1. We performed computational docking of the interacting domains in Smurf1 and LMPs to identify the key amino acid residues involved in their binding regions. In support of the computational predictions, we also present biochemical evidence supporting the hypothesis that the physical interaction of Smurf1 and osteoinductive forms of LMP may prevent Smurf1 from targeting osteogenic Smads by ubiquitin-mediated proteasomal degradation. 相似文献
119.
Tatsunori Masatani Naoto Ito Yuki Ito Keisuke Nakagawa Masako Abe Satoko Yamaoka Kota Okadera Makoto Sugiyama 《Microbiology and immunology》2013,57(7):511-517
By using a cultured neuroblastoma cell line, the present authors recently showed that the N protein of virulent rabies virus fixed strain Nishigahara (Ni), but not that of the attenuated derivative Ni‐CE, mediates evasion of induction of type I interferon (IFN). In this study, to determine whether Ni N protein indeed fulfills this function in vivo, the abilities to suppress IFN responses in the mouse brain of Ni‐CE and the virulent chimeric virus CE(NiN), which has the N gene from Ni in the genetic background of Ni‐CE, were compared. It was demonstrated that CE(NiN) propagates and spreads more efficiently than does Ni‐CE in the brain and that IFN response in brains infected with CE(NiN) is weaker than in those infected with Ni‐CE. It was also shown that amino acids at positions 273 and 394 in the N protein, which are known as pathogenic determinants, affect the ability of the viruses to suppress IFN response in the brain. These findings strongly suggest that, in the brain, rabies virus N protein plays important roles in evasion of innate immune responses and thereby in efficient propagation and spread of virus leading to lethal outcomes of infection. 相似文献
120.