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Cell-death can be necrosis and apoptosis. We are investigating the mechanisms regulating the cell death that occurs on treatment of mouse cancer cell-line FM3A with antitumor 5-fluoro-2''-deoxyuridine (FUdR): necrosis occurs for the original clone F28-7, and apoptosis for its variant F28-7-A. Here we report that a microRNA (miR-351) regulates the cell death pattern. The miR-351 is expressed strongly in F28-7-A but only weakly in F28-7. Induction of a higher expression of miR-351 in F28-7 by transfecting an miRNA mimic into F28-7 resulted in a change of the death mode; necrosis to apoptosis. Furthermore, transfection of an miR-351 inhibitor into F28-7-A resulted in the morphology change, apoptosis to necrosis, in this death-by-FUdR. Possible mechanism involving lamin B1 in this miR-351’s regulatory action is discussed.  相似文献   
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Rheological properties of sea urchin eggs   总被引:10,自引:0,他引:10  
Y Hiramoto 《Biorheology》1970,6(3):201-234
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Kidney bean (Phaseolus vulgaris) alpha-amylase inhibitors, which are bivalent inhibitors with the subunit stoichiometry of (alphabeta)(2) complex, have been inferred to contain unique arginine, tryptophan, and tyrosine residues essential for the inhibitory activity. To test the validity of this inference, an attempt was made to identify the essential amino acid residues of a white kidney bean (P. vulgaris) alpha-amylase inhibitor (PHA-I) by using the chemical modification technique combined with amino acid sequencing and mass spectrometry. Exhaustive modification of the arginine residues by phenylglyoxal did not lead to a marked loss of activity, suggesting that no arginine residue is directly associated with the inhibitory activity. N-Bromosuccinimide treatment of PHA-I in the presence or absence of a substrate alpha-amylase revealed the involvement of two tryptophan residues in alpha-amylase inhibition, and they were identified as Trp188 of the beta-subunit by amino acid sequencing and mass spectrometry of lysylendopeptidase peptides. Further, two tyrosine residues were preferentially modified either by N-acetylimidazole or by tetranitromethane, resulting in a concomitant loss of most of the PHA-I activity. Amino acid sequencing of the lysylendopeptidase peptides from a tetranitromethane-modified PHA-I identified Tyr186 of the beta-subunit as an essential residue.  相似文献   
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In this study, we synthesized a new cell immobilization support having poly(glycidyl methacrylate) as a graft polymer chain and used this support for cell cultivation. Base polymer particle was synthesized by suspension polymerization and epoxy polymer chain was extended from particle surface on graft polymerization. Produced polymer particles had broad particle size distribution ranging from 20 to 1000 μm and the degree of polymerization of grafted polymer chain was ranged from 500 to 1000. The effects of various factors, such as grafted polymer chain length and its surface density, composition of base polymer network and graft polymer chain, on the cell growth of murine fibroblast cell line (MS-5 cell) on polymer particle were studied. This polymer particle could cultivate not only fibroblast cell line but also epidermal cell line (HeLa cell), osteoblast cell line (MC3T3E1 cell), and chondrocyte cell line (ch-8 cell) on its surface. Growth rate is almost the same as that of cells using poly(styrene) tissue culture dish. To apply this cell cultivation system for examination of cell co-culture, HeLa cell immobilized on 100 μm of polymer particle was successfully co-cultured with MS-5 cell immobilized on 300 μm of polymer particle for four weeks.  相似文献   
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Background

Previous studies have shown that the practice of yoga reduces perceived stress and negative feelings and that it improves psychological symptoms. Our previous study also suggested that long-term yoga training improves stress-related psychological symptoms such as anxiety and anger. However, little is known about the beneficial effects of yoga practice on somatization, the most common stress-related physical symptoms, and stress-related biomarkers. We performed a prospective, single arm study to examine the beneficial effects of 12 weeks of yoga training on somatization, psychological symptoms, and stress-related biomarkers.

Methods

We recruited healthy women who had no experience with yoga. The data of 24 participants who were followed during 12 weeks of yoga training were analyzed. Somatization and psychological symptoms were assessed before and after 12 weeks of yoga training using the Profile of Mood State (POMS) and the Symptom Checklist-90-Revised (SCL-90-R) questionnaires. Urinary 8-hydroxydeoxyguanosine (8-OHdG), biopyrrin, and cortisol levels were measured as stress-related biomarkers. The Wilcoxon signed-rank test was used to compare the stress-related biomarkers and the scores of questionnaires before and after 12 weeks of yoga training.

Results

After 12 weeks of yoga training, all negative subscale scores (tension-anxiety, depression, anger-hostility, fatigue, and confusion) from the POMS and somatization, anxiety, depression, and hostility from the SCL-90-R were significantly decreased compared with those before starting yoga training. Contrary to our expectation, the urinary 8-OHdG concentration after 12 weeks of yoga training showed a significant increase compared with that before starting yoga training. No significant changes were observed in the levels of urinary biopyrrin and cortisol after the 12 weeks of yoga training.

Conclusions

Yoga training has the potential to reduce the somatization score and the scores related to mental health indicators, such as anxiety, depression, anger, and fatigue. The present findings suggest that yoga can improve somatization and mental health status and has implications for the prevention of psychosomatic symptoms in healthy women.

Trial registration

University Hospital Medical Information Network (UMIN CTR) UMIN000007868.  相似文献   
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Purpose

A proton beam therapy (PBT) system has been designed which dedicates to spot-scanning and has a gating function employing the fluoroscopy-based real-time-imaging of internal fiducial markers near tumors. The dose distribution and treatment time of the newly designed real-time-image gated, spot-scanning proton beam therapy (RGPT) were compared with free-breathing spot-scanning proton beam therapy (FBPT) in a simulation.

Materials and Methods

In-house simulation tools and treatment planning system VQA (Hitachi, Ltd., Japan) were used for estimating the dose distribution and treatment time. Simulations were performed for 48 motion parameters (including 8 respiratory patterns and 6 initial breathing timings) on CT data from two patients, A and B, with hepatocellular carcinoma and with clinical target volumes 14.6 cc and 63.1 cc. The respiratory patterns were derived from the actual trajectory of internal fiducial markers taken in X-ray real-time tumor-tracking radiotherapy (RTRT).

Results

With FBPT, 9/48 motion parameters achieved the criteria of successful delivery for patient A and 0/48 for B. With RGPT 48/48 and 42/48 achieved the criteria. Compared with FBPT, the mean liver dose was smaller with RGPT with statistical significance (p<0.001); it decreased from 27% to 13% and 28% to 23% of the prescribed doses for patients A and B, respectively. The relative lengthening of treatment time to administer 3 Gy (RBE) was estimated to be 1.22 (RGPT/FBPT: 138 s/113 s) and 1.72 (207 s/120 s) for patients A and B, respectively.

Conclusions

This simulation study demonstrated that the RGPT was able to improve the dose distribution markedly for moving tumors without very large treatment time extension. The proton beam therapy system dedicated to spot-scanning with a gating function for real-time imaging increases accuracy with moving tumors and reduces the physical size, and subsequently the cost of the equipment as well as of the building housing the equipment.  相似文献   
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