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61.
Cohesin release is required for sister chromatid resolution,but not for condensin-mediated compaction,at the onset of mitosis 总被引:10,自引:0,他引:10
The establishment of metaphase chromosomes is an essential prerequisite of sister chromatid separation in anaphase. It involves the coordinated action of cohesin and condensin, protein complexes that mediate cohesion and condensation, respectively. In metazoans, most cohesin dissociates from chromatin at prophase, coincident with association of condensin. Whether loosening of cohesion at the onset of mitosis facilitates the compaction process, resolution of the sister chromatids, or both, remains unknown. We have found that the prophase release of cohesin is completely blocked when two mitotic kinases, aurora B and polo-like kinase (Plx1), are simultaneously depleted from Xenopus egg extracts. Condensin loading onto chromatin is not affected under this condition, and rod-shaped chromosomes are produced that show an apparently normal level of compaction. However, the resolution of sister chromatids within these chromosomes is severely compromised. This is not because of inhibition of topoisomerase II activity that is also required for the resolution process. We propose that aurora B and Plx1 cooperate to destabilize the sister chromatid linkage through distinct mechanisms that may involve phosphorylation of histone H3 and cohesin, respectively. More importantly, our results strongly suggest that cohesin release at the onset of mitosis is essential for sister chromatid resolution but not for condensin-mediated compaction. 相似文献
62.
Shin Kobayashi Hiraku Uemura Takashi Kohda Toshiro Nagai Yasutsugu Chinen Kenji Naritomi Ei‐ichi Kinoshita Hirofumi Ohashi Kiyoshi Imaizumi Masato Tsukahara Yoshitsugu Sugio Hidefumi Tonoki Tatsuya Kishino Toshiaki Tanaka Masao Yamada Osamu Tsutsumi Norio Niikawa Tomoko Kaneko‐Ishino Fumitoshi Ishino 《American journal of medical genetics. Part A》2001,104(3):225-231
Silver‐Russell syndrome (SRS) is characterized by prenatal and postnatal growth retardation with morphologic anomalies. Maternal uniparental disomy 7 has been reported in some SRS patients. PEG1/MEST is an imprinted gene on chromosome 7q32 that is expressed only from the paternal allele and is a candidate gene for SRS. To clarify its biological function and role in SRS, we screened PEG1/MEST abnormalities in 15 SRS patients from various standpoints. In the lymphocytes of SRS patients, no aberrant expression patterns of two splice variants (α and β) of PEG1/MEST were detected when they were compared with normal samples. Direct sequence analysis failed to detect any mutations in the PEG1/MEST α coding region, and there were no significant mutations in the 5′‐flanking upstream region containing the predicted promoter and the highly conserved human/mouse genomic region. Differential methylation patterns of the CpG island for PEG1/MEST α were normally maintained and resulted in the same pattern as in the normal control, suggesting that there was no loss of imprinting. These findings suggest that PEG1/MEST can be excluded as a major determinant of SRS. © 2001 Wiley‐Liss, Inc. 相似文献
63.
Yoshiteru Hasegawa Tatsuya Kasai Toshio Tsuji Susumu Yahagi 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,140(4):387-396
We have reexamined the contradictory evidence in which task-dependent excitation of motor evoked potentials (MEPs) in the first dorsal interosseous (FDI) muscle was stronger with increasingly more complex finger tasks than with individual finger movement tasks. In the first step of the experiment, based on previous findings, we investigated remarkable functional differences between intrinsic and extrinsic hand muscles during complex finger tasks (precision and power grip). During the performance of the tasks, the optimal stimulus intensity of the transcranial magnetic stimulation (TMS) was applied to the contralateral motor cortex. MEPs of the FDI, extensor carpi radialis (ECR), and flexor carpi radialis (FCR) muscles were recorded simultaneously with increased background EMG activity step by step in both tasks. The intensity threshold of TMS was lower in the precision grip. Furthermore, the MEP amplitudes of FDI muscle dependent on the background EMG activity were different between these two tasks, i.e., MEP amplitudes and regression coefficients in a precision grip were larger than those in a power grip. Although our results for MEP amplitude and threshold in the FDI muscle were similar to previous reported evidence, the different contributions of a synergistic muscle (in particular, the ECR muscle) during performance in these tasks was new evidence. Since there were no differences in cutaneous afferent effects on both tasks, corticomotoneuronal (CM) cells connected to FDI motoneurons seemed generally to be more active during precision than power gripping, and there were different contributions from synergistic muscles during the performance of these tasks. In the second part of the experiment, the results obtained from the complex tasks were compared with those from a simple task (isolated index finger flexion). MEP amplitudes, dependent on the background EMG activity during isolated index finger flexion, varied among subjects, i.e., the relationship between the MEP amplitude and the background EMG of the FDI muscle showed individual, strategy-dependent modulation. There were several kinds of individual motor strategies for performing the isolated finger movement. The present results may explain the previous contradictory evidence related to the contribution of the CM system during coordinated finger movement. 相似文献
64.
Hideyuki Arima Yu Yamato Kimihito Sato Yoshihiro Uchida Toshiyuki Tsuruta Kanehisa Hashiguchi Hajime Hamamoto Eiichiro Watanabe Kaoru Yamanaka Tomohiko Hasegawa Go Yoshida Tatsuya Yasuda Tomohiro Banno Shin Oe Hiroki Ushirozako Tomohiro Yamada Koichiro Ide Yuh Watanabe Yukihiro Matsuyama 《Journal of orthopaedic science》2021,26(4):577-583
BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ 相似文献
65.
Wada Takehiko Ishimoto Takuji Nakaya Izaya Kawaguchi Takehiko Sofue Tadashi Shimizu Sayaka Kurita Noriaki Sasaki Sho Nishiwaki Hiroki Koizumi Masahiro Saito Shoji Nishibori Nobuhiro Oe Yuji Yoshida Mai Miyaoka Yoshitaka Akiyama Shin’ichi Itano Yuya Okazaki Masaki Ozeki Takaya Ichikawa Daisuke Oguchi Hideyo Kohsaka Satoshi Kosaka Shiho Kataoka Yuki Shima Hideaki Shirai Sayuri Sugiyama Kazuhiro Suzuki Tomo Son Daisuke Tanaka Tomomi Nango Eishu Niihata Kakuya Nishijima Yoko Nozu Kandai Hasegawa Midori Miyata Rei Yazawa Masahiko Yamamoto Yoshihiro Yamamoto Ryohei Shibagaki Yugo Furuichi Kengo Okada Hirokazu Narita Ichiei 《Clinical and experimental nephrology》2021,25(12):1277-1285
Clinical and Experimental Nephrology - 相似文献
66.
Yosuke Tsuruga Toshiya Kamiyama Hirofumi Kamachi Tatsuya Orimo Shingo Shimada Akihisa Nagatsu Yoh Asahi Yuzuru Sakamoto Tatsuhiko Kakisaka Akinobu Taketomi 《World journal of gastrointestinal surgery》2021,13(2):153-163
BACKGROUNDPreoperative portal vein embolization (PVE) is a widely used strategy to enable major hepatectomy in patients with insufficient liver remnant. PVE induces hypertrophy of the future liver remnant (FLR) and a shift of the functional reserve to the FLR. However, whether the increase of the FLR volume (FLRV) corresponds to the functional transition after PVE remains unclear.AIMTo investigate the sequential relationship between the increase in FLRV and functional transition after preoperative PVE using 3-dimensional (3D) computed tomography (CT) and 99mTc-galactosyl-human serum albumin (99mTc-GSA) single-photon emission computed tomography (SPECT) fusion images. METHODSThirty-three patients who underwent major hepatectomy following PVE at the Department of Gastroenterological Surgery I, Hokkaido University Hospital between October 2013 and March 2018 were enrolled. Three-phase dynamic multidetector CT and 99mTc-GSA SPECT scintigraphy were performed at pre-PVE, and at 1 and 2 wk after PVE; 3D 99mTc-GSA SPECT CT-fused images were constructed from the Digital Imaging and Communications in Medicine data using 3D image analysis system. Functional FLRV (FFLRV) was defined as the total liver volume × (FLR volume counts/total liver volume counts) on the 3D 99mTc-GSA SPECT CT-fused images. The calculated FFLRV was compared with FLRV.RESULTSFFLRV increased by a significantly larger extent than FLRV at 1 and 2 wk after PVE (P < 0.01). The increase in FFLRV and FLRV was 55.1% ± 41.6% and 26.7% ± 17.8% (P < 0.001), respectively, at 1 wk after PVE, and 64.2% ± 33.3% and 36.8% ± 18.9% (P < 0.001), respectively, at 2 wk after PVE. In 3 of the 33 patients, FFLRV levels decreased below FLRV at 2 wk. One of the three patients showed rapidly progressive fatty changes in FLR. The biopsy at 4 wk after PVE showed macro- and micro-vesicular steatosis of more than 40%, which improved to 10%. Radical resection was performed at 13 wk after PVE. The patient recovered uneventfully without any symptoms of pos-toperative liver failure.CONCLUSIONThe functional transition lagged behind the increase in FLRV after PVE in some cases. Evaluating both volume and function is needed to determine the optimal timing of hepatectomy after PVE. 相似文献
67.
Yuko Kaneyasu Hisaya Fujiwara Tetsuo Nishimura Hideyuki Sakurai Tomoko Kazumoto Hitoshi Ikushima Takashi Uno Sunao Tokumaru Yoko Harima Hiromichi Gomi Takafumi Toita Midori Kita Shin-ei Noda Takeo Takahashi Shingo Kato Ayako Ohkawa Akiko Tozawa-Ono Hiroki Ushijima Yoko Hasumi Yasuyuki Hirashima Yuzuru Niibe Tomio Nakagawa Tomoyuki Akita Junko Tanaka Tatsuya Ohno the Working Group of the Gynecological Tumor Committee of the Japanese Radiation Oncology Study Group 《Journal of radiation research》2021,62(2):269
This study aimed to research the post-treatment quality of life (QOL) between radiotherapy (RT)- and operation (OP)-treated early cervical cancer survivors, using separate questionnaires for physicians and patients. We administered an observational questionnaire to patients aged 20–70 years old with Stages IB1–IIB cervical cancer who had undergone RT or OP and without recurrence as outpatients for ≥6 months after treatment. We divided 100 registered patients equally into two treatment groups (n = 50 each). The average age was 53 and 44 years in the RT and OP groups, respectively. The RT group included 34 and 66% Stage I and II patients, respectively, whereas the OP group included 66 and 34% Stage I and II patients, respectively. The OP group included 58% of patients with postoperative RT. Combination chemotherapy was performed in 84 and 48% of patients in the RT and OP groups, respectively. On the physicians’ questionnaire, we observed significant differences in bone marrow suppression (RT) and leg edema (OP). On the patients’ questionnaire, significantly more patients had dysuria and leg edema in the OP group than in the RT group, and severe (Score 4–5) leg edema was significantly higher in the post-operative RT group than in the OP only group. The frequency of sexual intercourse decreased after treatment in both groups. On the patients’ questionnaire, there were no significant differences between the two groups regarding sexual activity. These findings are useful to patients and physicians for shared decision-making in treatment choices. The guidance of everyday life and health information including sexual life after treatment is important. 相似文献
68.
Sezai A Shiono M Orime Y Nakata K Hata M Iida M Kashiwazaki S Kinoshita J Nemoto M Koujima T Furuichi M Eda K Hirose H Yoshino T Saitoh A Taniguchi Y Sezai Y 《Artificial organs》1999,23(3):280-285
We examined a major organ function during 3 h biventricular assisted circulation after acute myocardial infarction model in the pig. In left ventricular circulation, the outflow cannula was placed in the ascending aorta and an inflow cannula through the mitral valve in the left ventricle. A pump (pulsatile group, Zeon Medical, Inc., Tokyo, Japan and nonpulsatile group, Nikkiso HPM-15, Nikkiso, Inc., Tokyo, Japan) was connected to each cannula. In right ventricular circulation, the outflow cannula was placed in the pulmonary artery and an inflow cannula in the right ventricle. The right ventricular circulation was supported by a nonpulsatile pump (Nikkiso HPM-15). The items measured were the regional blood flows of the cortex and medulla in the kidney, white matter and gray mater in brain, and liver; renal arterial flow; carotid arterial flow; portal vein flow; common hepatic arterial flow; arterial ketone body ratio (AKBR); and lactate/pyrubic acid (L/P). In the pulsatile group, the renal cortical blood flow increased, and the medulla blood flow decreased. On the other hand, in the nonpulsatile group, both regional blood flows decreased. That means that in the pulsatile assisted group intrarenal redistribution improved rather than in the nonpulsatile assisted group. In addition the liver regional blood flow, AKBR, and L/P showed significant differences between the pulsatile and nonpulsatile groups. On the other hand, the white matter and gray matter regional blood flows and carotid arterial flow did not show significant differences between the groups. The results of our study indicated that pulsatile circulation produced superior circulation in the kidney and liver, and microcirculation on the cell level was superior as well in early treatment of acute heart failure. 相似文献
69.
Yokota K Johyama Y Yamaguchi K Fujikt Y Takeshita T Morimoto K 《Environmental health and preventive medicine》1996,1(3):133-135
Methylterahydrophthalic anhydride (MTHPA) is used as a hardening agent in an epoxy resin system. Because work-related nasal symptoms were observed in some workers exposed toMTHPA at two condenser plants, a cross-sectional survey was performed to improve their work environment. MeanMTHPA levels in the manufacturing processes to which the workers were routinely assigned were extremely low (1.09-22.4 μg/m3). However, specific IgE antibody (S-IgE) was detected in 9 (32%) of 28 workers. Of these, 8 (89%) had nasal symptoms. An IgE-mediated mechanism seems to be associated with at least some of the cases of work-related nasal symptoms. This indicates that the occupational health administration ofMTHPA cannot be controlled simply by limiting exposure in the work environment. Total IgE (T-IgE) levels were significantly higher in S-IgE-positive workers than in S-IgE-negative workers (geometric mean, 200.5 and 51.3 IU/ml, respectively; p<0.002, unpaired t test). These findings demonstrate that workers in whom S-IgE is less likely to be produced, i.e., those in whom the T-IgE level is 80 IU/ml or less, should be assigned to work in these manufacturing processes. 相似文献
70.
Shiraishi M Suzuki K Abe T Kikuchi T Satoh H Nakaji S Sugawara K 《Environmental health and preventive medicine》1996,1(2):65-70
Neutrophil functions, including chemotaxis, reactive oxygen species (ROS)-producing capacity of neutrophils, and serum opsonic activity were investigated in 9 young healthy male volunteers. Venous blood of these volunteers was obtained under standardized conditions at 4-h intervals over a 24-h span. Neutrophil chemotaxis was evaluated by a modified Boyden technique, ROS-producing capacity of neutrophils and serum opsonic activity were measured by a simultaneous multiple measurement system based on luminol-dependent chemiluminescence and indicated by peak height and peak time. ROS-producing capacity of neutrophils and serum opsonic activity were activated in the daytime, and decreased from night to morning. There were negative correlations between the peak time of the luminol-dependent chemiluminescent response, neutrophil number (p<0.01) and segmented neutrophil number (p>0.01). On the other hand, no significant correlations were noted between serum opsonic activity and IgG, IgA, IgM, C3 or C4. In contrast, the peaks of neutrophil chemotaxis were at the wake-up time (6:00a.m.) and in the evening (6:00p.m.). This study indicates that diurnal variation of neutrophil function exists. 相似文献