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121.
122.
Masakatsu Fujinoki Tatsuya Suzuki Takeshi Takayama Hiroaki Shibahara Hideki Ohtake 《Reproductive Medicine and Biology》2006,5(2):123-135
Background and Aims It has been widely accepted that sperm hyperactivation is regulated by protein phosphorylations. But, the sperm hyperactivation
phosphorylation pathway is not well understood yet because several different proteins have been detected in other studies.
In order to understand the phosphorylation pathway that regulates hyperactivation, we established how to extract sperm protein
completely and detected proteins that were phosphorylated during hyperactivation.
Methods Protein phosphorylation of hamster spermatozoa was detected by western blotting using antiphospho-amino acid monoclonal antibodies
or the SELDI ProteinChip system with IMAC-Ga(III).
Results We detected 75 protein/peptide phosphoryations using the method established in the present study. Tyrosine phosphorylations
occurred during hyperactivation. Serine or threonine phosphorylations occurred for 30 min. Furthermore, four of the serine
or threonine phosphorations were phosphorylated by A-kinase. As for peptides, 15 peptides were dephosphorylated for 30 min.
Other peptides were phosphorylated during hyperactivation.
Conclusions Because most of the proteins detected in the present study have been described previously, we could detect comprehensive protein
phosphorylations. Moreover, we also detected many novel phosphopeptides. Although we did not understand the role of peptide,
it was likely that motility was basically regulated by serine/threonine phosphorylations and hyperactivation was mainly regulated
by tyrosine phosphorylations. (Reprod Med Biol 2006; 5: 123–135) 相似文献
123.
Takao Imai Noriaki Takeda Mahito Ito Koji Nakamae Hideki Sakae Hiromu Fujioka Takeshi Kubo 《Otology & neurotology》2006,27(3):362-366
OBJECTIVE: To show the positional nystagmus in a patient who had suffered from benign paroxysmal positional vertigo (BPPV) that was thought to be caused by involvement of the anterior semicircular canal (ASCC) (A-BPPV). STUDY DESIGN: Retrospective case report. SETTING: City hospital. PATIENT: The present study reports a rare case of A-BPPV in a 41-year-old woman. CASE REPORT: The patient is 41-year-old woman who developed a positional vertigo after playing volleyball on March 22, 2005 and consulted our hospital the next day. When left Dix-Hallpike maneuver was performed, she showed a positional nystagmus of which fast phase direction of the torsional component was clockwise while that of the vertical component was downward. We plotted the slow phase eye velocity of the positional nystagmus during the left Dix-Hallpike maneuver on three-dimensional coordinates that showed the axis of the positional nystagmus to be perpendicular to the plane of the right ASCC. CONCLUSION: These results suggested that the patient was suffering from A-BPPV. 相似文献
124.
Caffeine induces apoptosis of human umbilical vein endothelial cells through the caspase-9 pathway. 总被引:2,自引:0,他引:2
Shozo Matsuoka Toshitake Moriyama Noriyuki Ohara Kenji Tanimura Takeshi Maruo 《Gynecological endocrinology》2006,22(1):48-53
Caffeine is known to modulate placental and fetal umbilical circulation. It is demonstrated that apoptosis of human umbilical vein endothelial cells (HUVECs) is associated with placental umbilical vascular diseases. The present study was conducted to investigate the effects of caffeine on apoptosis of HUVECs. Isolated HUVECs were cultured under serum-free conditions for 24 h, and then treated with graded concentrations of caffeine (30, 100 and 300 microM) for additional 24 h and 48 h. The number of viable HUVECs was determined by cell counting. Apoptotic HUVECs were assessed by Hoechst33342 dye staining. The expression of caspase-9, caspase-8, caspase-3 and poly(ADP-ribose) polymerase (PARP) was assessed by Western blot analysis. Caffeine induced a dose- and time-dependent decrease in the number of viable HUVECs. Caffeine at concentrations higher than 100 microM significantly increased the percentage of apoptotic HUVECs. Caffeine at concentrations higher than 100 microM significantly increased cleaved caspase-9, caspase-3 and PARP expression in HUVECs at 24-h treatment compared with untreated cultures, whereas 30 microM caffeine significantly increased only caspase-3 expression at 24 h. Caffeine did not affect cleaved caspase-8 expression at 48 h. These results suggest that high concentrations of caffeine inhibit cell growth of HUVECs and induce apoptosis through the caspase-9 pathway. 相似文献
125.
126.
127.
Kazunori Mawatari Toyohisa Katsumata Masanobu Uematsu Tomoyoshi Katsumata Junichi Yoshida Miro Smriga Takeshi Kimura 《Food and chemical toxicology》2004,42(9):1505-1511
L-leucine, an essential amino acid, is one of the most popular ingredients in dietary supplements. To investigate a possibility of its embryo-fetal toxicity in rats, 11- to 12-week old dams were orally administered an aqueous solution of L-leucine at doses of 300 or 1000 mg/kg body weight on gestational days 7-17. Body weight and feed intake was evaluated throughout the whole course of pregnancy (days 0-20). L-Leucine did not influence body weight, but at a dose of 1000 mg/kg, slightly enhanced feed intake on days 14 and 18 of pregnancy. Caesarean section (day 20) revealed no influences on the litter size and weight of live-born fetuses, the number of corpora lutea, implantation index or the quality of placenta, and the minor increase in feed intake was considered irrelevant to the pregnancy outcomes. Fetuses were evaluated in a battery of external, visceral and skeletal examinations. No effects of L-leucine on gender ratio and external abnormalities, and no significant treatment-related variations in visceral and skeletal pathologies were observed. These results suggested that L-leucine, administered orally during organogenesis at doses up to 1000 mg/kg body weight, did not affect the outcome of pregnancy and did not cause fetotoxicity in rats. 相似文献
128.
A 78-year-old woman complained of severe pain in the left costal region. Her body mass index was 23.1 kg/m2. Lateral cutaneous nerve entrapment syndrome (LACNES) was the suspected diagnosis because the affected area was 2×2 cm and positive for pinch sign. Seventeen days later, the patient again presented with complaints of lower back pain accompanied by back pain upon extending the spine. Magnetic resonance imaging of the spine showed a fracture of the vertebral body of T11. We herein discuss our errors in the diagnostic process and critical tactics for avoiding such errors in the future. 相似文献
129.
Kubota Y Yano Y Seki S Takada K Sakuma M Morimoto T Akaike A Hiraide A 《American journal of pharmaceutical education》2011,75(3):43
Objective
To determine the value of using the Roter Interaction Analysis System during objective structured clinical examinations (OSCEs) to assess pharmacy students'' communication competence.Methods
As pharmacy students completed a clinical OSCE involving an interview with a simulated patient, 3 experts used a global rating scale to assess students'' overall performance in the interview, and both the student''s and patient''s languages were coded using the Roter Interaction Analysis System (RIAS). The coders recorded the number of utterances (ie, units of spoken language) in each RIAS category. Correlations between the raters'' scores and the number and types of utterances were examined.Results
There was a significant correlation between students'' global rating scores on the OSCE and the number of utterances in the RIAS socio-emotional category but not the RIAS business category.Conclusions
The RIAS proved to be a useful tool for assessing the socio-emotional aspect of students'' interview skills. 相似文献130.
Junichi Mazaki Kenji Katsumata Tetsuo Ishizaki Noritoshi Fukushima Ryutaro Udo Tomoya Tago Kenta Kasahara Hiroshi Kuwabara Masanobu Enomoto Yuichi Nagakawa Akihiko Tsuchida 《Medicine》2022,101(27)
Anastomotic leakage (AL) after colorectal surgery is a serious complication. This study aimed to evaluate the effectiveness of the EEA™ circular stapler, a new triple-row circular stapler (TCS), relative to a conventional, double-row circular stapler (DCS).A total of 285 patients who underwent anastomosis with the double stapling technique at the Tokyo Medical University Hospital between 2017 and 2021 were included in this nonrandomized clinical trial with historical controls using a propensity score (PS) analysis. The primary endpoint was the risk of AL.We performed a 1:2 PS matching analysis. Before case matching, AL occurred in 15 (7.4%) and 2 (2.4%) patients in the DCS and TCS groups, respectively, with no significant difference (P = .17). After case matching, AL occurred in 13 patients (11.6%) and 1 patient (1.8%) in the DCS and TCS groups, respectively, revealing a significant difference (P = .04). Cox models were created by applying PS to adjust for group differences via regression adjustment. Odds ratios for AL in the DCS group versus the TCS group were 0.31 (95% confidence interval [CI]: 0.07–1.38) in the entire cohort, 0.15 (95% CI: 0.02–0.64) in the regression adjustment cohort, and 0.14 (95% CI: 0.02–1.09) in the 1:2 PS-matched cohort.PS analysis of clinical data suggested that the use of TCS contributes to a reduced risk of AL after colorectal anastomosis CTwith the double stapling technique. 相似文献