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1.
Abstract— A basic protein fraction capable of inducing experimental allergic neuritis was isolated from peripheral nervous tissues of ox and rabbit. The electrophoretic mobility was lower than that of lysozyme at pH 4 , 2 and 8 , 2. The yield was approximately 0 , 1 g per cent of fresh tissue weight.  相似文献   
2.
Postural muscle activity pattern was examined in the eyes-closed state after adequate adaptation to floor anteroposterior oscillation. Twenty-three subjects were grouped almost evenly according to dominance of anterior or posterior postural muscles in the trunk and thigh during quiet stance. In the posterior-dominant group, this dominance was maintained at every frequency in most subjects. In the anterior-dominant group, this dominance was maintained in most subjects at 0.1 and 0.5 Hz but changed to posterior dominance at 1.0 and 1.5 Hz in about half the subjects. Periodicity of muscle activity was evaluated by EMG amplitude spectrum at the floor oscillation frequency. Periodicity of posterior-dominant muscles in the trunk and thigh increased with increasing oscillatory frequency. In the trunk, the periodicity did not differ significantly between posterior-dominant and anterior-dominant groups. However, in the thigh, periodicity was significantly lower in the anterior-dominant muscles. This was considered to be caused by nonperiodic alternating action of the anterior and posterior muscles. In the lower leg, posterior dominance was observed in quiet stance and at all oscillation frequencies. Periodicity of soleus and gastrocnemius increased at higher frequencies and was higher in gastrocnemius than in soleus. The periodicity difference between both muscles decreased with increasing oscillation frequency.  相似文献   
3.

Background

Adaptation changes in postural control and contingent negative variation (CNV) for the elderly were investigated during repeated forward floor translation.

Methods

Fifteen healthy elderly persons, living in the suburban area of Kanazawa City, Japan, underwent backward postural disturbance by a forward-floor translation (S2) 2 s after an auditory warning signal (S1). A set with 20 trials was repeated until a negative peak of late CNV was recognized in the 600-ms period before S2, and the last set was defined as the final set. Electroencephalograms, center of foot pressure in the anteroposterior direction (CoPap), and electromyograms of postural muscles were analyzed.

Results

CoPap displacement generated by the floor translation was significantly decreased until the twelfth trial in the first set, and mean CoPap displacement was smaller in the second and final sets than in the first set. The mean displacement was significantly smaller in the final set than the previous set. A late CNV with a negative peak was not recognized in the first and second sets. However, most subjects (13/15) showed a negative peak by the fourth set, when the late CNV started to increase negatively from about 1,000 ms after S1 and peaked at about 300 ms before S2. At about 160 ms before the CNV peak, the CoPap forward shift started. The increase in timing of the gastrocnemius activity related to the CoPap shift was significantly correlated with the CNV peak timing (r = 0.64). After S2, peak amplitudes of the anterior postural muscles were significantly decreased in the final set compared to the first set.

Conclusions

It was demonstrated that even for the elderly, with so many repetitions of postural disturbance, a late CNV with a negative peak was recognized, leading to accurate postural preparation. This suggests the improvement of frontal lobe function (e.g., anticipatory attention and motor preparation) in the elderly.  相似文献   
4.
Elucidation of how pancreatic cancer cells give rise to distant metastasis is urgently needed in order to provide not only a better understanding of the underlying molecular mechanisms, but also to identify novel targets for greatly improved molecular diagnosis and therapeutic intervention. We employed combined proteomic technologies including mass spectrometry and isobaric tags for relative and absolute quantification peptide tagging to analyze protein profiles of surgically resected human pancreatic ductal adenocarcinoma tissues. We identified a protein, dihydropyrimidinase-like 3, as highly expressed in human pancreatic ductal adenocarcinoma tissues as well as pancreatic cancer cell lines. Characterization of the roles of dihydropyrimidinase-like 3 in relation to cancer cell adhesion and migration in vitro, and metastasis in vivo was performed using a series of functional analyses, including those employing multiple reaction monitoring proteomic analysis. Furthermore, dihydropyrimidinase-like 3 was found to interact with Ezrin, which has important roles in cell adhesion, motility, and invasion, while that interaction promoted stabilization of an adhesion complex consisting of Ezrin, c-Src, focal adhesion kinase, and Talin1. We also found that exogenous expression of dihydropyrimidinase-like 3 induced activating phosphorylation of Ezrin and c-Src, leading to up-regulation of the signaling pathway. Taken together, the present results indicate successful application of combined proteomic approaches to identify a novel key player, dihydropyrimidinase-like 3, in pancreatic ductal adenocarcinoma tumorigenesis, which may serve as an important biomarker and/or drug target to improve therapeutic strategies.  相似文献   
5.
Spatial genetic structure (SGS) of plants mainly depends on the effective population size and gene dispersal. Maternally inherited loci are expected to have higher genetic differentiation between populations and more intensive SGS within populations than biparentally inherited loci because of smaller effective population sizes and fewer opportunities of gene dispersal in the maternally inherited loci. We investigated biparentally inherited nuclear genotypes and maternally inherited chloroplast haplotypes of microsatellites in 17 tree populations of three wild cherry species under different conditions of tree distribution and seed dispersal. As expected, interpopulation genetic differentiation was 6–9 times higher in chloroplast haplotypes than in nuclear genotypes. This difference indicated that pollen flow 4–7 times exceeded seed flow between populations. However, no difference between nuclear and chloroplast loci was detected in within‐population SGS intensity due to their substantial variation among the populations. The SGS intensity tended to increase as trees became more aggregated, suggesting that tree aggregation biased pollen and seed dispersal distances toward shorter. The loss of effective seed dispersers, Asian black bears, did not affect the SGS intensity probably because of mitigation of the bear loss by other vertebrate dispersers and too few tree generations after the bear loss to alter SGS. The findings suggest that SGS is more variable in smaller spatial scales due to various ecological factors in local populations.  相似文献   
6.
Differentiation of placental trophoblast stem (TS) cells to trophoblast giant (TG) cells is accompanied by transition from a mitotic cell cycle to an endocycle. Here, we report that Cdh1, a regulator of the anaphase-promoting complex/cyclosome (APC/C), negatively regulates mitotic entry upon the mitotic/endocycle transition. TS cells derived from homozygous Cdh1 gene-trapped (Cdh1GT/GT) murine embryos accumulated mitotic cyclins and precociously entered mitosis after induction of TS cell differentiation, indicating that Cdh1 is required for the switch from mitosis to the endocycle. Furthermore, the Cdh1GT/GT TS cells and placenta showed aberrant expression of placental differentiation markers. These data highlight an important role of Cdh1 in the G2/M transition during placental differentiation.  相似文献   
7.
Dysregulation of cell cycle machinery causes abnormal cell division, leading to cancer development. To drive cell cycle properly, expression levels of cell cycle regulators are tightly regulated through the cell cycle. Dual specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2) is a Ser/Thr kinase, and its intracellular functions had not been elucidated for decades. Recent studies have shown that DYRK2 down-regulates key molecules on cell cycle control. This review mainly highlights the DYRK2 function during cell division. In addition, we summarize tumor suppressive role of DYRK2 in cancer cells and discuss future research directions for DYRK2 toward the novel cancer therapies.  相似文献   
8.
9.
Applied Microbiology and Biotechnology - A β-1,4-mannanase, termed AoMan134A, that belongs to the GH 134 family was identified in the filamentous fungus Aspergillus oryzae. Recombinant...  相似文献   
10.

Purpose

Oxycodone is a µ-opioid receptor agonist widely used in the treatment of cancer pain. The predominant metabolic pathway of oxycodone is CYP3A4-mediated N-demethylation to noroxycodone, while a minor proportion undergoes 3-O-demethylation to oxymorphone by CYP2D6. The aim of this study was to investigate the effects of the mild CYP3A4 inhibitor aprepitant on the pharmacokinetics of orally administered controlled-release (CR) oxycodone.

Method

This study design was an open-label, single-sequence with two phases in cancer patients with pain who continued to be administered orally with multiple doses of CR oxycodone every 8 or 12 hours. Plasma concentration of oxycodone and its metabolites were measured up to 8 hours after administration as follows: on day 1, CR oxycodone was administered alone; on day 2, CR oxycodone was administered with aprepitant (125 mg, at the same time of oxycodone dosing in the morning). The steady-state trough concentrations (Css) were measured from day 1 to day 3.

Results

Aprepitant increased the area under the plasma concentration-time curve (AUC0–8) of oxycodone by 25% (p<0.001) and of oxymorphone by 34% (p<0.001), as well as decreased the AUC0–8 of noroxycodone by 14% (p<0.001). Moreover, aprepitant increased Css of oxycodone by 57% (p = 0.001) and of oxymorphone by 36% (p<0.001) and decreased Css of noroxycodone by 24% (p = 0.02) at day 3 compared to day 1.

Conclusions

The clinical use of aprepitant in patients receiving multiple doses of CR oxycodone for cancer pain significantly altered plasma concentration levels, but would not appear to need modification of the CR oxycodone dose.

Trial Registration

UMIN.ac.jp UMIN000003580.  相似文献   
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