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991.
Beneficial effect of coronary artery bypass grafting as assessed by quantitative gated single-photon emission computed tomography. 总被引:2,自引:0,他引:2
Satoshi Hida Taishiro Chikamori Tetsuzo Hirayama Yasuhiro Usui Hidefumi Yanagisawa Takayuki Morishima Shin Ishimaru Akira Yamashina 《Circulation journal》2003,67(6):499-504
The development of quantitative gated single-photon emission computed tomography (SPECT) has enabled the assessment of left ventricular perfusion, function and wall thickness in a single examination. Accordingly, the present study used gated SPECT to assess the benefit of coronary artery bypass grafting (CABG) in patients with coronary artery disease; 47 of those patients were evaluated before and 5 months after CABG. As a result of coronary revascularization, a significant improvement was observed in global ejection fraction (50+/-12 --> 53+/-11%; p<0.05). In 107 revascularized territories, the average regional reversible defect score (0.8+/-0.5 --> 0.2 +/-0.3; p<0.0001), average regional perfusion score at rest (0.6+/-0.6 --> 0.3+/-0.4; p<0.0001), average regional wall motion score (0.9+/-0.7 --> 0.7+/-0.5; p<0.05), and end-diastolic wall thickness (8.1+/-1.3 --> 8.6+/-1.5 mm; p<0.0005) all improved significantly. Even in 34 non-revascularized territories, the average regional reversible defect score (0.5+/-0.7 --> 0.2+/-0.5; p<0.03), average regional wall motion score (0.8+/-1.1 --> 0.5 +/-1.0; p<0.03) and end-diastolic wall thickness (8.0+/-1.4 --> 9.1+/-2.0 mm; p<0.03) all improved significantly. These results indicate that improvement in myocardial ischemia, hibernation and left ventricular function with CABG can be assessed in detail with gated SPECT. 相似文献
992.
Bone marrow mononuclear cell therapy
limits myocardial infarct size through vascular endothelial
growth factor 总被引:13,自引:0,他引:13
Hiasa K Egashira K Kitamoto S Ishibashi M Inoue S Ni W Zhao Q Nagata S Katoh M Sata M Takeshita A 《Basic research in cardiology》2004,99(3):165-172
Abstract. No prior study has examined the effect of intravenous
injection of bone marrow mononuclear cells (MNCs) on myocardial
infarction size (IS). We tested the hypothesis that
transplantation of MNCs decreases IS through the release of
vascular endothelial growth factor (VEGF). Immediately after
ligation of the left coronary artery of immunodeficient mice,
PBS or MNCs were intravenously administered. Myocardial IS was
significantly less in MNCs-treated mice than in PBS-treated
mice. Trace experiments showed accumulation of exogenously
administered MNCs into the vicinity of infarcted myocardium.
Injection of MNCs did not affect capillary density after
infarction, but did reduced myocardial cell apoptosis. Blockade
of VEGF by a neutralizing antibody or by gene transfer of a
soluble form of Flt-1 VEGF receptor diminished the IS-limiting
effects of MNCs. In conclusion, injection of MNCs can reduce
myocardial IS through the release of VEGF. The MNC therapy for
acute myocardial infarction might improve prognosis of patients
with myocardial infarction. 相似文献
993.
Plasma asymmetric dimethylarginine and coronary and peripheral endothelial dysfunction in hypertensive patients 总被引:9,自引:0,他引:9
Takiuchi S Fujii H Kamide K Horio T Nakatani S Hiuge A Rakugi H Ogihara T Kawano Y 《American journal of hypertension》2004,17(9):802-808
BACKGROUND: The attenuation of coronary flow reserve (CFR) and endothelium-mediated vasodilation of the brachial artery (EMV-BA) have been frequently reported in hypertensive patients. The present study investigated the link between CFR and EMV-BA in hypertensive patients. We hypothesized that changes in serum asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, and concomitant insulin resistance may be underlying factors connecting the two pathologic alterations. METHODS: A total of 75 patients (30 men and 45 women, 61.5 +/- 10.1 years of age) with essential hypertension and without coronary artery disease and diabetes mellitus were included in the study. Measurements of CFR were made using adenosine-triphosphate stress transthoracic Doppler echocardiography, and forearm EMV-BA was measured by venous occlusion strain gauge plethysmography. A plasma ADMA assay and a 75-g oral glucose tolerance test were also performed. RESULTS: Average CFR and EMV-BA values were 2.54 +/- 0.63 and 86.0 +/- 54.7%, respectively. A significant correlation was found between CFR and EMV-BA (r = 0.493, P <.001). Both CFR and EMV-BA were also significantly correlated with age and plasma ADMA concentration, but were not correlated with insulin resistance, plasma insulin, or left ventricular mass. Multiple regression analysis revealed that ADMA was the only statistically independent parameter associated with CFR and EMV-BA. CONCLUSIONS: The similar deterioration in endothelial function in coronary and peripheral vascular territories may be mainly due to increased plasma ADMA concentration. Plasma ADMA appears to play a major role in endothelial dysfunction in hypertensive patients, independent of insulin resistance or left ventricular hypertrophy. 相似文献
994.
Hyoung Jin Kang Keon Hee Yoo Ji Won Lee Hyery Kim Soo Hyun Lee Ki Woong Sung Kyung Duk Park Hong Hoe Koo Hee Young Shin Hyo Seop Ahn 《Annals of hematology》2010,89(10):1035-1044
Umbilical cord blood transplantation (UCBT) with two units has been conducted with promising results in adults to overcome
the limitation of low cell numbers. In an attempt to improve the outcomes, double UCBT was performed in children and adolescents.
Sixty-one patients, including 44 acute leukemia, and 17 other hematologic diseases, received double UCBT. Donor-type engraftment
achieved in 82% of patients. Except one patient with persistent mixed chimerism of two units, other 49 patients showed dominancy
of one unit and only the CFU-GM was significant factor influencing dominancy. The event-free survival (EFS) of leukemia and
other hematologic disease were 59% and 53%, respectively, and the EFS of acute leukemia patients who received transplant in
first or second CR (68.6%) was significantly better than in those with advanced disease (22.2%) (P = 0.007). Among the factors influencing outcomes, low cell dose difference between two units (TNC difference/TNC of large
unit <15%) were associated with higher TRM, relapse, and lower EFS. Double UCBT was a promising modality of transplant in
children and adolescence. However, engraftment and other results were not so satisfactory yet. To improve the outcomes, development
of new selection guideline, probably including cell dose difference between two units and technology to enhance engraftment
and reduce transplantation-related mortality are warranted. 相似文献
995.
Kota Ouchi Shin Takahashi Akira Okita Yasuhiro Sakamoto Osamu Muto Kenji Amagai Takaho Okada Hisatsugu Ohori Eiji Shinozaki Chikashi Ishioka 《Cancer science》2022,113(3):1057
DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting. 相似文献
996.
ObjectiveThe purpose of this study was to estimate 5-year conditional relative survival (5Y CRS) rates of endometrial cancer (EC) in Korea accounting for time already survived. Subgroup-specific estimates stratified by various patient characteristics were also presented.MethodsUsing the data from the Korean Central Cancer Registry, 5Y CRS rates were calculated in patients who were diagnosed with EC between 1998 and 2017. The CRS rates were presented by year of diagnosis, age at diagnosis, histology, cancer stage, and treatment received.ResultsThe 5-year relative survival rate at the time of diagnosis was 89.0% for all cases. The probability of surviving an additional 5 years (i.e., 5Y CRS), if the patient survived 1, 2, 3, 4, and 5 years after diagnosis was 91.8%, 94.1%, 95.6%, 96.5%, and 97.3%, respectively. Patients with poor initial prognoses, i.e., those who were older, had non-endometrioid histology, and high stage, showed the largest improvements in 5Y CRS, reaching >90% for most subgroups, except those with serous histology (88.4%) and distant stage (77.7%). Patients aged ≥70 years had the highest probability of death in the 1st and 2nd years after diagnosis (13.8 and 11.0%), but the conditional probability of death in the 3rd, 4th, and 5th years declined rapidly to 7.3%, 4.5%, and 3.7%, respectively.ConclusionThe CRS rates for patients with EC improved with increased time elapsed from diagnosis. The greatest improvements in 5Y CRS were observed among patients who were older, those with non-endometrioid histology, and those with more advanced disease. 相似文献
997.
Huayin Wu Yinan Shen Suganya Sivagurunathan Miriam Sarah Weber Stephen A. Adam Jennifer H. Shin Jeffrey J. Fredberg Ohad Medalia Robert Goldman David A. Weitz 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(10)
The cytoskeleton of eukaryotic cells is primarily composed of networks of filamentous proteins, F-actin, microtubules, and intermediate filaments. Interactions among the cytoskeletal components are important in determining cell structure and in regulating cell functions. For example, F-actin and microtubules work together to control cell shape and polarity, while the subcellular organization and transport of vimentin intermediate filament (VIF) networks depend on their interactions with microtubules. However, it is generally thought that F-actin and VIFs form two coexisting but separate networks that are independent due to observed differences in their spatial distribution and functions. In this paper, we present a closer investigation of both the structural and functional interplay between the F-actin and VIF cytoskeletal networks. We characterize the structure of VIFs and F-actin networks within the cell cortex using structured illumination microscopy and cryo-electron tomography. We find that VIFs and F-actin form an interpenetrating network (IPN) with interactions at multiple length scales, and VIFs are integral components of F-actin stress fibers. From measurements of recovery of cell contractility after transient stretching, we find that the IPN structure results in enhanced contractile forces and contributes to cell resilience. Studies of reconstituted networks and dynamic measurements in cells suggest direct and specific associations between VIFs and F-actin. From these results, we conclude that VIFs and F-actin work synergistically, both in their structure and in their function. These results profoundly alter our understanding of the contributions of the components of the cytoskeleton, particularly the interactions between intermediate filaments and F-actin.The cytoskeleton is a highly dynamic structure composed of multiple types of filamentous proteins. In eukaryotic cells, actin, microtubules, and intermediate filaments (IFs) each form intricate networks of entangled and cross-linked filaments. The organization of each individual network is precisely controlled to enable essential cellular functions. However, many core processes also require interactions among the different cytoskeletal components. For example, filamentous-actin (F-actin) and microtubules work together to control cell shape and polarity, which are critical for development, cell migration, and division. Close associations between microtubules and vimentin IFs (VIFs) have also been proposed based on similarities in their spatial distributions and the dependence of the organization of VIF networks on the microtubule-associated motors, kinesin and dynein (1–3). Indeed, there is some experimental evidence that microtubules can template VIF assembly and that VIFs can guide microtubules (4, 5), while VIFs stabilize microtubules in vitro (6). In addition, in stratified epithelial cells, a subplasmalemmal rim of keratin IFs can be localized just below the actin cortex, suggesting cooperativity of keratin and actin networks in regulating cell mechanics (7). Despite such interactions, VIFs and F-actin are generally thought to form two coexisting but separate networks. For example, fluorescence microscopy typically reveals the strongest signals for F-actin in the cell periphery, whereas the strongest signals for VIFs are near the nucleus in the bulk cytoplasm, suggesting that the two networks have little or no interaction. Furthermore, the functions of F-actin and VIFs appear to be largely contrasting: F-actin generates forces, whereas VIFs provide stability against these forces. Nevertheless, some evidence suggests there may be connections between vimentin and actin: for example, vimentin knockout cells are less motile and less contractile than their wild-type (WT) counterparts (8). Furthermore, some interactions have been observed between F-actin and VIFs (9–11) as well as the precursors to keratin, another IF system (12). These findings suggest that direct interactions or connections may exist between VIFs and F-actin. However, there have been no reports of direct observations of these interactions through imaging or other means, which would provide conclusive evidence of their significance. Such connections would belie our current understanding of the two independent cytoskeletal networks but could have a profound effect on the mechanical properties of cells. The possibility of such connections demands a closer investigation of both the structural and functional interplay between the F-actin and VIF cytoskeletal networks.Here we present evidence that VIFs and F-actin do work synergistically and form an interpenetrating network (IPN) structure within the cell cortex, defined as the cortical cytoplasm adjacent to the cell surface. We combine high-resolution structured illumination microscopy (SIM) and cryo-electron tomography (cryo-ET) to image mouse embryonic fibroblasts (MEFs) and observe coupling between F-actin and VIF structures within the cortex, contrary to the widely accepted view that they are each spatially segregated. In fact, the association of VIFs with cortical arrays of F-actin stress fibers occurs at multiple length scales. For example, VIFs run through and frequently appear to interconnect with adjacent stress fibers, forming meshworks that surround them. These organizational states are consistent with the formation of an IPN. We show that this IPN structure has important functional consequences in cells and can result in enhanced contractile forces. Moreover, our results indicate that specific associations exist between actin and vimentin proteins in the cytoplasmic environment, which may facilitate the formation of an IPN; the results also show that the VIF network can influence the diffusive behavior of actin monomers, which may, in turn, have downstream effects on other actin-driven processes. Thus, vimentin has a far more comprehensive role in cellular function than previously thought. These findings confirm the importance of the interplay between VIFs and F-actin, especially as it relates to the formation of IPNs and their consequences on the contractile nature of cells. 相似文献
998.
Jong-Ho Ha Ryoong Huh Shin-Gyeom Kim Soo-Bin Im Je Hoon Jeong Sun-Chul Hwang Dong-Seong Shin Bum-Tae Kim Moonyoung Chung 《Journal of Korean Neurosurgical Society》2022,65(2):276
ObjectiveSpinal cord stimulation (SCS) is an effective treatment for chronic neuropathic pain. However, its clinical efficacy in regard to specific types of pain has not been well studied. The primary objective of this study was to retrospectively analyze the clinical outcomes of paddle-type SCS according to the type of neuropathic pain. MethodsSeventeen patients who underwent paddle-lead SCS at our hospital were examined. Clinical outcomes were evaluated pre- and postoperatively (3 months, 1 year, and last follow-up) using the Neuropathic Pain Symptom Inventory (NPSI). The NPSI categorizes pain as superficial, deep, paroxysmal, evoked, or dysesthesia and assess the duration of the pain (pain time score). Changes in NPSI scores were compared with change in Visual analogue scale (VAS) scores. ResultsAfter SCS, the pain time score improved by 45% (independent t-test, p=0.0002) and the deep pain score improved by 58% (independent t-test, p=0.001). Improvements in the pain time score significantly correlated with improvements in the VAS score (r=0.667, p=0.003, Spearman correlation). Additionally, the morphine milligram equivalent value was markedly lower after vs. before surgery (~49 mg, pared t-test, p=0.002). No preoperative value was associated with clinical outcome. ConclusionThe NPSI is a useful tool for evaluating the therapeutic effects of SCS. Chronic use of a paddle-type spinal cord stimulation improved the deep pain and the pain time scores. 相似文献
999.
Shinji Ueno Yusuke Seino Shihomi Hidaka Ryuya Maekawa Yuko Takano Michiyo Yamamoto Mika Hori Kana Yokota Atsushi Masuda Tatsuhito Himeno Shin Tsunekawa Hideki Kamiya Jiro Nakamura Hitoshi Kuwata Haruki Fujisawa Megumi Shibata Takeshi Takayanagi Yoshihisa Sugimura Daisuke Yabe Yoshitaka Hayashi Atsushi Suzuki 《Nutrients》2022,14(5)
(1) Background: Protein stimulates the secretion of glucagon (GCG), which can affect glucose metabolism. This study aimed to analyze the metabolic effect of a high-protein diet (HPD) in the presence or absence of proglucagon-derived peptides, including GCG and GLP-1. (2) Methods: The response to HPD feeding for 7 days was analyzed in mice deficient in proglucagon-derived peptides (GCGKO). (3) Results: In both control and GCGKO mice, food intake and body weight decreased with HPD and intestinal expression of Pepck increased. HPD also decreased plasma FGF21 levels, regardless of the presence of proglucagon-derived peptides. In control mice, HPD increased the hepatic expression of enzymes involved in amino acid metabolism without the elevation of plasma amino acid levels, except branched-chain amino acids. On the other hand, HPD-induced changes in the hepatic gene expression were attenuated in GCGKO mice, resulting in marked hyperaminoacidemia with lower blood glucose levels; the plasma concentration of glutamine exceeded that of glucose in HPD-fed GCGKO mice. (4) Conclusions: Increased plasma amino acid levels are a common feature in animal models with blocked GCG activity, and our results underscore that GCG plays essential roles in the homeostasis of amino acid metabolism in response to altered protein intake. 相似文献
1000.
Kazuomi Kario YookChin Chia Saulat Siddique Yuda Turana Yan Li ChenHuan Chen Jennifer Nailes Minh Van Huynh Peera Buranakitjaroen HaoMin Cheng Takeshi Fujiwara Satoshi Hoshide Michiaki Nagai Sungha Park Jinho Shin Jorge Sison Arieska Ann Soenarta Guru Prasad Sogunuru Apichard Sukonthasarn Jam Chin Tay Boon Wee Teo Kelvin Tsoi Narsingh Verma TzungDau Wang Yuqing Zhang JiGuang Wang 《Journal of clinical hypertension (Greenwich, Conn.)》2022,24(3):213
Asia is a large continent and there is significant diversity between countries and regions. Over the last 30 years, absolute blood pressure (BP) levels in Asia have increased to a greater extent than those in other regions. In diverse Asia‐Pacific populations, for choosing an Asia‐specific approach to hypertension management is important to prevent target organ damage and cardiovascular diseases. In this consensus document of HOPE Asia Network, we introduce seven action approaches for management of hypertension in Asia. 相似文献