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91.
Suppression and acceleration of cell elongation by integration of xyloglucans in pea stem segments 下载免费PDF全文
Takeda T Furuta Y Awano T Mizuno K Mitsuishi Y Hayashi T 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(13):9055-9060
Xyloglucan is a key polymer in the walls of growing plant cells. Using split pea stem segments and stem segments from which the epidermis had been peeled off, we demonstrate that the integration of xyloglucan mediated by the action of wall-bound xyloglucan endotransglycosylase suppressed cell elongation, whereas that of its fragment oligosaccharide accelerated it. Whole xyloglucan was incorporated into the cell wall and induced the rearrangement of cortical microtubules from transverse to longitudinal; in contrast, the oligosaccharide solubilized xyloglucan from the cell wall and maintained the microtubules in a transverse orientation. This paper proposes that xyloglucan metabolism controls the elongation of plant cells. 相似文献
92.
Shinichi Kiso Sumio Kawata Shinji Tamura Yasuharu Imai Yoshiaki Inui Toshihiko Nagase Yuichi Maeda Eiji Yamasaki Hirofumi Tsushima Takumi Igura Seiichi Himeno Kouichi Seki Yuji Matsuzawa 《Journal of gastroenterology》1997,32(1):56-62
The efficacy of interferon- therapy in the treatment of chronic hepatitis C is still limited. A combination therapy of interferon- with ursodeoxycholic acid (UDCA) was tested for its efficacy in the treatment of chronic hepatitis C by a randomized controlled study. Eighty consecutive Japanese patients with chronic hepatitis C were randomly divided into two groups: one group was treated with interferon- (group A,n=40) and the other with a combination of interferon- and UDCA (group B,n=40). In both groups, human interferon- (6 million units per day) was intramuscularly injected daily for 2 weeks and then three times a week for 22 weeks: this 24-week period was followed by 24 weeks of observation. In group B, UDCA was also administered, daily at a dose of 600mg orally, from the beginning of the interferon therapy and administration was continued for 48 weeks. The rates for ALT normalization and clearance of hepatitis C virus (HCV) viremia at the end of the 24-week interferon therapy were similar for groups A and B (58% vs 60% and 55% vs 48%, respectively). At the end of the 24-week follow-up, the sustained normalization rates for ALT levels for the two groups were not different (35% vs 43%), while the rate of clearance was higher in group B (40%) than in group A (23%), but the difference was not significant (P=0.14). The sustained complete response, i.e., HCV RNA negativity at the end of the follow-up, as well as the maintenance of ALT normalization during the follow-up period, was more frequent in group B (38%) than in group A (18%) although the difference was not significantP=0.08). The rate of HCV reactivation after interferon was discontinued was significantly lower in group B (16%) than in group A (59%) (P<0.01). Although this combination therapy did not lead to a sufficiently sustained complete response, it could serve as adjuvant antiviral therapy when a suitable dosage and administration period are determined. 相似文献
93.
Takumi Sumimoto Takaaki Ochi Taketoshi Ito Tadafumi Joh Shinjiro Muneta Kunio Hiwada 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1997,11(1):27-32
The aim of this study was to compare the effects of a calcium antagonist, nicardipine SR, with an angiotensin-converting enzyme (ACE) inhibitor, alacepril, on the regression of left ventricular hypertrophy (LVH) and function. Twenty patients with LVH, aged 42–73 years, were treated with nicardipine SR or alacepril. Ten patients were treated with nicardipine SR (40–80 mg) for 21 months, and the other 10 patients were treated with alacepril (25–100 mg) for 18 months. All patients underwent echocardiography to assess left ventricular structure and function before and after the treatment. After nicardipine SR or alacepril treatment, blood pressure was decreased significantly from 176.0 ± 13.9/97.0 ± 5.3 mmHg to 140.0 ± 14.0/77.4 ± 7.2 mmHg and from 168.2 ± 22.3/99.0 ± 5.5 mmHg to 138.4 ± 12.5/85.2 ± 9.7 mmHg, respectively (both p < 0.01), whereas heart rate did not change (73.8 ± 14.6 beats/min vs. 69.9 ± 13.5 beats/min and 71.6 ± 9.7 vs. 65.8 ± 8.1 beats/min, respectively). The left ventricular mass index decreased significantly from 133.2 ± 11.7 g/m2 to 114.4 ± 15.7 g/m2 with nicardipine SR and from 137.1 ± 14.8 g/m2 to 99.3 ± 23.0 g/m2 with alacepril (both p < 0.01). The fractional shortening, peak shortening rate, and peak lengthening rate all improved significantly after each treatment. The end-systolic wall stress/left ventricular end-systolic volume index, as an index of left ventricular contractility, was decreased significantly after treatment with nicardipine SR but was not changed after treatment with alacepril. In conclusion, both nicardipine SR and alacepril similarly reduced LVH and improved left ventricular systolic and diastolic function. However, alacepril did not alter left ventricular contractility, whereas nicardi-pine SR decreased left ventricular contractility. 相似文献
94.
Generation of transgenic mice with elevated blood pressure by introduction of the rat renin and angiotensinogen genes. 总被引:5,自引:2,他引:5 下载免费PDF全文
H Ohkubo H Kawakami Y Kakehi T Takumi H Arai Y Yokota M Iwai Y Tanabe M Masu J Hata et al. 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(13):5153-5157
The role of the renin-angiotensin system in blood pressure control and in the development of hypertension was investigated by generating transgenic mice carrying the rat renin or angiotensinogen gene or both genes under the control of the mouse metallothionein I promoter. The systolic blood pressure was significantly elevated in transgenic mice carrying both transgenes but was maintained normally in those bearing either of the transgenes. The transgene was effectively and properly transcribed to form the mature mRNA in the transgenic mice. The production of rat renin and angiotensinogen in the transgenic mice carrying the corresponding transgene was also verified by immunoanalyses of these proteins. Furthermore, the specific angiotensin-converting enzyme inhibitor captopril was effective in reducing the elevated blood pressure of the hypertensive transgenic mice. These results indicate that the combined action of the exogenous rat renin and angiotensinogen is responsible and necessary for elevation of blood pressure in the hypertensive transgenic mice. 相似文献
95.
Intra-articular injection of high molecular weight hyaluronan after arthrocentesis as treatment for rheumatoid knees with joint effusion 总被引:7,自引:0,他引:7
Tanaka N Sakahashi H Sato E Hirose K Ishima T Ishii S 《Rheumatology international》2002,22(4):151-154
OBJECTIVE: The aim of this study was to find if a complete synovial fluid aspiration before injection of intra-articular high molecular weight hyaluronan influences the treatment result for knees with rheumatoid arthritis (RA), including joint effusion and the prognostic factors related to clinical effect. METHODS: The arthritic knees including effusion were randomized to arthrocentesis or no arthrocentesis before the hyaluronan (1.9-2.5 x 10(6)) was injected into knee joints five times every week. All patients were followed up for 6 months. RESULTS: One hundred eighteen RA patients (80 knees in the arthrocentesis group, 81 knees in the no-arthrocentesis group) were included. The proportion of no relapses in the arthrocentesis group was higher than that in the no-arthrocentesis group. In the arthrocentesis group, regression analysis showed that duration of knee arthritis (<5 months), CRP (<4 mg/dl), and Larsen grade (相似文献
96.
97.
Yunjung Choi Hyunju Kim Moonseok Choi Eun-Jeong Yang Toru Takumi Hye-Sun Kim 《Journal of pharmacological sciences》2019,139(3):249-253
The duplication of human chromosome 15q11-13 is known to be associated with an estimated 1.1% of autism cases. Here, we investigated whether differentiation into neurons and astrocytes is altered in fetal neural stem cells (FNSCs) isolated from the mouse model of 15q11-13 duplication syndrome (patDp/+ mice). In patDp/+ mice-derived FNSCs, multipotency was maintained for a longer period, the population of neurons was downregulated, and that of astrocytes was upregulated significantly after differentiation induction. These results suggest that the dysregulation of FNSCs differentiation could affect cortical development and behavioral deficits in the early postnatal stage shown in the patDp/+ mice. 相似文献
98.
Koki Yamamura Masao Doi Hida Hayashi Takumi OtaIori Murai Yunhong HottaRie Komatsu Hitoshi Okamura 《Molecular and cellular endocrinology》2014
The enzyme 3β-hydroxysteroid dehydrogenase/isomerase (3β-HSD) is essential for the biosynthesis of all active steroid hormones, such as those secreted from the adrenal gland, testis, ovary, skin and placenta. The 3β-HSD enzymes exist in multiple isoforms in humans and rodents. To date, six different isoforms have been identified in the mouse, and these isoforms are speculated to play different roles in different tissues. We previously showed that the murine type VI 3β-HSD isoform (Hsd3b6) is expressed specifically in the aldosterone-producing zona glomerulosa cells within the adrenal gland and that its overexpression causes abnormally increased aldosterone synthesis, revealing a crucial (or rate-limiting) role of this enzyme in steroidogenesis. However, potential contributions of this enzyme to the steroid hormone synthesis outside the adrenal glands are poorly understood. This paucity of knowledge is partly because of the lack of isoform-specific antibody that can be used for immunohistochemistry. Here, we report the development and characterization of specific antibody to Hsd3b6 and show the results of immunohistochemistry for the adrenal gland, testis, ovary, skin and placenta. As expected, Hsd3b6 immunoreactivities within the adrenal gland were essentially confined to the zona glomerulosa cells, where aldosterone is produced. By contrast, no immunopositive cells were observed in the zona fasciculata, which is where corticosterone is produced. In the gonads, while the ovaries did not show any detectable immunoreactivity to Hsd3b6, the testes displayed intense immunoreactivities within the interstitial Leydig cells, where testosterone is produced. In the skin, positive immunoreactivities to Hsd3b6 were only seen in the sebaceous glands, suggesting a specific role of this enzyme in sebaceous function. Moreover, in the placenta, Hsd3b6 was specifically found in the giant trophoblast cells surrounding the embryonic cavity, which suggests a role for this enzyme in local progesterone production that is required for proper embryonic implantation and/or maintenance of pregnancy. Taken together, our data revealed that Hsd3b6 is localized in multiple specific tissues and cell types, perhaps thereby involved in biosynthesis of a number of tissue-specific steroid hormones with different physiological roles. 相似文献
99.
Yasuaki Hayashino Jeffrey L. Jackson Takumi Hirata Norio Fukumori Fumiaki Nakamura Shunichi Fukuhara Satoru Tsujii Hitoshi Ishii 《Metabolism: clinical and experimental》2014
Objective
C-reactive protein (CRP), inflammatory cytokines, and adipokines contribute to atherosclerosis, insulin resistance, and development of late-onset complication in patients with type 2 diabetes. We performed a systematic review to assess effects of exercise interventions on inflammatory markers/cytokines and adipokines.Materials/Methods
We searched electronic databases (MEDLINE, EMBASE, and Cochrane Controlled Trials Registry) and reference lists in relevant papers for articles published in 1966–2013. We selected studies that evaluated the effects of exercise intervention on inflammatory markers/cytokines and adipokines in adult patients with type 2 diabetes. Weighted mean differences of exercise on outcomes were derived using fixed or random effect models; factors influencing heterogeneity were identified using meta-regression analysis.Results
Fourteen randomized controlled trials (824 patients) were included in our meta-analysis. Exercise was associated with a significant in CRP = − 0.66 mg/l (95% CI, − 1.09 to − 0.23 mg/l; − 14% from baseline) and interleukin-6 (IL-6) = − 0.88 pg/ml (95% CI, − 1.44 to − 0.32 pg/ml; − 18% from baseline) but did not alter adiponectin or resistin levels; aerobic exercise program was associated with a significant change in leptin = − 3.72 ng/ml (95% CI, − 6.26 to − 1.18 ng/ml; − 24% from baseline). For IL-6, exercise was more effective in those with a longer duration in the program and larger number of sessions during study (p = 0.001).Conclusions
Exercise decreases inflammatory cytokine (CRP and IL-6) in patients with type 2 diabetes. Exercise could be a therapeutic option for improving abnormalities in inflammation levels in patients with diabetes. 相似文献100.
Shinichi Kako Yoshinobu Kanda Makoto Onizuka Nobuyuki Aotsuka Kensuke Usuki Takayoshi Tachibana Takeshi Kobayashi Jun Kato Shingo Yano Hiroaki Shimizu Katsuhiro Shono Masatsugu Tanaka Shokichi Tsukamoto Takehiko Mori Etsuko Yamazaki Yuho Najima Akira Hangaishi Takumi Hoshino Reiko Watanabe Kenji Matsumoto Shinichiro Okamoto for Kanto Study Group for Cell Therapy 《American journal of hematology》2020,95(3):251-257
The optimal pre-transplant conditioning for aplastic anemia (AA) remains unclear. We performed a prospective study on allogeneic transplantation from a related or unrelated donor for adult patients with AA. We assessed whether reduced-dose cyclophosphamide (CY) could decrease toxicity while maintaining engraftment, and low-dose thymoglobulin could safely prevent graft-vs-host disease (GVHD). The pre-transplant conditioning regimen consisted of fludarabine 120 mg/m2, CY 100 mg/kg, and thymoglobulin 2.5 mg/kg with or without 2 Gy of total body irradiation. Twenty-seven patients with a median age of 36 years were analyzed. Sixteen patients received graft from related donors. The stem cell source was bone marrow in 26 patients. All of the patients but one, who died early, achieved neutrophil engraftment at a median of 19 days. Mixed chimerism was observed in six and five patients at days 30 and 90, respectively. Only one patient experienced secondary engraftment failure with complete donor-type chimerism. None of the patients developed severe acute GVHD. The cumulative incidence of chronic GVHD was 37.7% at 1 year. The overall survival rate was 96.3% at 1 year and 3 years. A high EB virus-DNA load was detected in one patient at days 60. No one developed EBV-lymphoproliferative disorder within a year. The results suggest that the conditioning regimen in this study was safe and effective. However, relatively high incidence of chronic GVHD needs further improvement. 相似文献