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41.
Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function 总被引:4,自引:4,他引:4
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function. 相似文献
42.
Ji Ho Choi Seung Hoon Lee Jae Hoon Cho Sung Wan Kim Kyu Sup Cho Soo Kweon Koo Tae-Bin Won Jeong-Whun Kim Hyo Yeol Kim Yoo Suk Kim Yoo-Sam Chung Chae-Seo Rhee 《Clinical and experimental otorhinolaryngology》2015,8(4):370-375
Objectives
To evaluate the effect of obstructive sleep apnea (OSA) surgery on long-term (5-year) subjective outcomes, including sleep disordered breathing (SDB) symptoms and other complications, in patients with OSA.Methods
We enrolled patients who underwent diagnostic polysomnography for OSA between January 2006 and December 2006 in ten hospitals. Patients either were treated for OSA or were not treated for OSA. All patients completed a brief telephone survey regarding their SDB signs and symptoms (e.g., snoring, apnea, nocturnal arousals, and daytime sleepiness), positive airway pressure (PAP) compliance, and any adverse effects of either the surgery or PAP. A positive subjective outcome for either surgery or no treatment was taken to be the alleviation of apnea, defined as a ≥50% increase in score. A positive subjective outcome (compliance) for PAP was defined as a PAP usage of ≥4 hours per night and ≥5 days per week.Results
A total of 229 patients were included in this study. Patients were divided into three groups: a surgery group (n=87), a PAP group (n=68), and a control (untreated) group (n=74). The surgery group exhibited significant improvement in all SDB symptoms compared with the control group. The long-term subjective outcomes of the surgery (52.9%) and PAP (54.4%) groups were significantly better than those of the control group (25.0%). The subjective outcome of the surgery group was not significantly different from that of the PAP group. The overall surgical complication rate was 23.0% (20 of 87) in the surgery group, and 55.0% (22 of 40) of all patients with PAP experienced adverse effects.Conclusion
The extent of SDB symptoms was consistently improved in patients with OSA at 5 years postsurgery. Information about the potential long-term subjective outcomes should be provided to patients when considering surgery. 相似文献43.
Tae-Min Rhee Kyung Woo Park Chi-Hoon Kim Jeehoon Kang Jung-Kyu Han Han-Mo Yang Hyun-Jae Kang Bon-Kwon Koo Hyo-Soo Kim 《JACC: Cardiovascular Interventions》2018,11(24):2453-2463
Objectives
The aim of this study was to investigate clinical outcomes after left main coronary artery (LM) bifurcation percutaneous coronary intervention (PCI) and the impact of the duration of dual antiplatelet therapy (DAPT) according to treatment strategy.Background
There are limited data regarding the optimal PCI strategy for LM bifurcation lesions with new-generation drug-eluting stents.Methods
A patient-level pooled analysis of 5 nationwide multicenter registries was performed. Rates of target lesion failure, thrombotic adverse cardiovascular events, and their individual components at 3-year were analyzed. Subgroup analysis according to DAPT duration was performed.Results
From 13,172 patients undergoing PCI with new-generation drug-eluting stents, a total of 700 patients were treated for LM bifurcation lesions, 567 with a 1-stent strategy and 133 with a 2-stent strategy. Rates of target lesion failure and target lesion revascularization were higher in the 2-stent group, driven mainly by complex lesion profiles. Risks for thrombotic adverse cardiovascular events and its components were comparable between the 2 strategies. Subgroup analysis showed that risks for target lesion failure and thrombotic adverse cardiovascular events in the 2-stent group were significantly higher than in the 1-stent group in those with DAPT interruption <1 year, while they were similar in those receiving DAPT maintenance ≥1 year.Conclusions
Up to 20% of patients who underwent LM bifurcation PCI eventually required a 2-stent strategy, which was as safe as a 1-stent strategy with the use of new-generation drug-eluting stents. Careful pre-emptive case selection as well as prolonged DAPT may be necessary when considering a 2-stent strategy in LM PCI given its higher rate of repeat revascularization and lesion failure than the 1-stent approach. 相似文献44.
AIMS: With increasing prevalence of diabetes mellitus and metabolic syndrome (MS), the importance of early detection of insulin resistance is emphasized. However, a simple and practical method of measurement is not readily available. Therefore, we examined the sensitivity and specificity of HbA(1c) for predicting impaired fasting glucose (IFG) and MS and its association with cardiovascular risk factors, particularly in the normal range of HbA(1c) levels in non-diabetic Korean subjects. METHODS: In 40,155 participants (median age 40 years) participating in a medical check-up programme, analysis of the distribution of HbA(1c) and its association with various cardiovascular risk factors was performed. In 22,465 selected participants, an analysis was conducted of the ability of HbA(1c) to predict MS and IFG. Anthropometric measurements were made in all subjects and fasting glucose, lipid profiles and HbA(1c) were measured. The presence of MS was defined according to the definitions of the Adult Treatment Panel III (ATP III) guideline and the new International Diabetes Federation (IDF) guideline. Patients with diabetes were excluded from the study. RESULTS: The incidence of MS was 12.2% according to ATP III criteria and 7.6% according to IDF criteria. When subjects were grouped by quartile of HbA(1c), cardiovascular risk factors significantly increased as the HbA(1c) increased. An HbA(1c) of 5.45% predicted the presence of MS (ATP III: sensitivity/specificity 57.4/64.3%, area under the curve 64.8%; IDF: sensitivity 60.2/63.4%, area under the curve 66.1%) and fasting blood glucose > or = 5.6 mmol/l (sensitivity/specificity 53.7/70%, area under the curve 66.1%). When the analyses were done separately by gender, female subjects showed higher cut-off of HbA(1c) for the prediction of MS (5.55% for both ATP III and IDF criteria). CONCLUSIONS: HbA(1c) increased as cardiovascular risk factors increased and HbA(1c) of 5.45% predicted the presence of MS. HbA(1c) might be a predictive measure of IFG and MS, and also cardiovascular risk factors in the Korean population. 相似文献
45.
The relationship between parent feeding styles and general parenting with loss of control eating in treatment‐seeking overweight and obese children 下载免费PDF全文
46.
Melissa Soohoo Elani Streja Yoshitsugu Obi Connie M. Rhee Daniel L. Gillen Keiichi Sumida Danh V. Nguyen Csaba P. Kovesdy Kamyar Kalantar-Zadeh 《Mayo Clinic proceedings. Mayo Clinic》2018,93(8):1074-1085
Objective
To determine whether kidney function level and its rate of decline in the immediate predialysis period among veterans transitioning to end-stage renal disease (ESRD) predict postdialysis mortality and hospitalization.Patients and Methods
In 19,985 veterans transitioning to ESRD during the period October 1, 2007, to March 30, 2014, we examined kidney function and its slope over the final year of the pre-ESRD(prelude) period. Two categories of low vs high estimated glomerular filtration rate (eGFR, dichotomized at 10 mL/min/1.73 m2) and slow vs fast slope (dichotomized at ?10 mL/min/1.73 m2/y) were combined into 4 groups. Their associations with 12-month post-ESRD all-cause and cardiovascular (CV) mortality and hospitalization rates were examined in adjusted models accounting for clinical characteristics and laboratory measurements at transition.Results
Patients, 66±11 years old, and 34% blacks, had a median (interquartile range) eGFR at transition and slope of 9.7 (7.1-13.3) mL/min/1.73 m2 and ?10.5 (?18.8 to ?5.9) mL/min/1.73 m2/y, respectively. Patients with a low eGFR and slow slope had the lowest 12-month all-cause and CV mortality risks and hospitalization rate. Conversely, patients with high eGFR and fast slope had the highest risk of all-cause and CV mortality and hospitalization rate compared with patients with a low eGFR and slow slope. This relationship persisted in sensitivity analyses, including propensity scoring.Conclusion
A kidney profile of a low eGFR and slow slope in the prelude period is associated with favorable early dialysis outcomes in veteran patients. Trials to examine a more conservative approach to dialysis are warranted. 相似文献47.
Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs). However, earlier models (e.g., the Kovacs model) cannot properly consider the roles of the interphase regions or tunneling properties on the percolation threshold and subsequent conductivity of PCNTs. In this paper, the Kovacs model is further developed by assuming that the CNT, interphase, and tunneling regions are separate phases. Also, some simple equations are provided to calculate the percolation threshold as well as the volume fractions and resistances of the CNT, interphase, and tunneling regions in conductive networks. The experimental conductivity results for several samples are compared with the predictions of the developed model. In addition, the calculations of the developed model at different parameter levels are explained and justified. The conductivity calculations show good agreement with the experimental data. Moreover, the developed model reasonably explains the roles of the different parameters on the conductivity. For example, long, thin, and straight CNTs efficiently improve the conductivity because they form large networks in the nanocomposites. Additionally, a thick interphase enlarges the conductive networks, resulting in a desirable conductivity. The conductivity of PCNTs only depends on the tunneling resistance; this is the case because the poor resistance/significant conductivity of the CNT and interphase regions do not influence the conductivity. The developed equations can replace conventional approaches for predicting the conductivity of nanocomposites.Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs). 相似文献
48.
Choi EY Ko YG Kim JB Rhee J Park S Choi D Jang Y Shim WH Cho SY 《The Journal of invasive cardiology》2005,17(9):459-462
Here, we evaluate the efficacy of the Clo-Sur PAD nonwoven hydrophilic wound dressing (HWD) on hemostasis in an arterial-access site after transradial percutaneous coronary angiography compared with the RadiStop compression device (CD). Eighty patients who had undergone transradial coronary angiography with or without intravascular ultrasound were randomly assigned to the HWD or CD group. The time required to achieve hemostasis was measured, and the incidence of vascular complications was assessed. No significant differences in clinical and procedural characteristics were observed between the HWD group (n = 40) and the CD group (n = 40). A significant reduction in the time required to achieve hemostasis (58.7 +/- 32.6 minutes versus 131.3 +/- 59.1 minutes; p < 0.001) was associated with the use of HWD. The incidence of vascular complications was similar in both groups (5% for HWD versus 2.5% for CD; p = 0.500). No major complications, such as large hematoma or acute radial occlusion, occurred in the HWD group. In conclusion, HWD represents a safe alternative to the compression method. Hemostasis can be achieved more quickly using HWD, with no increase in access site complications, as compared to CD. 相似文献
49.
Bortezomib down-regulates the cell-surface expression of HLA class I and enhances natural killer cell-mediated lysis of myeloma 总被引:1,自引:0,他引:1
Shi J Tricot GJ Garg TK Malaviarachchi PA Szmania SM Kellum RE Storrie B Mulder A Shaughnessy JD Barlogie B van Rhee F 《Blood》2008,111(3):1309-1317
Human leukocyte antigen class I molecules expressed by tumor cells play a central role in the regulation of natural killer (NK) cell-mediated immune responses. The proteasome inhibitor bortezomib has demonstrated significant activity in multiple myeloma (MM). We hypothesized that treatment of MM with bortezomib results in the reduction of cell-surface expression of class I and thereby sensitizes MM to NK cell-mediated lysis. Here we report that bortezomib down-regulates class I in a time- and dose-dependent fashion on all MM cell lines and patient MM cells tested. Downregulation of class I can also be induced in vivo after a single dose of 1.0 mg/m(2) bortezomib. Bortezomib significantly enhances the sensitivity of patient myeloma to allogeneic and autologous NK cell-mediated lysis. Further, the level of decrease in class I expression correlates with increased susceptibility to lysis by NK cells. Clinically relevant bortezomib concentrations do not affect NK-cell function. Our findings have clear therapeutic implications for MM and other NK cell-sensitive malignancies in the context of both allogeneic and autologous adoptively transferred NK cells. 相似文献
50.
June Sang Lee Tae Gun Moon Hoi Jin Kim Hyun Jeong Lee Jun Haeng Lee Sang Goon Shim Poong -Lyul Rhee Jae J Kim Jong-Chul Rhee 《Taehan Sohwagi Hakhoe chi》2007,49(4):231-237
BACKGROUND/AIMS: Internet has become an important source of medical information not only for medical personnels but also for patients. The aim of this study was to evaluate the quality of internet based medical information about 'gastroesophageal reflux' or 'reflux esophagitis' in Korea. METHODS: The first 15 internet sites using the key words 'gastroesophageal reflux' or 'reflux esophagitis' were retrieved from the 7 most frequently used internet search engines. The quality of information from a total of 108 websites was evaluated using a checklist. RESULTS: Among total 108 sites related to 'gastroesophageal reflux' or 'reflux esophagitis', fifty-six sites (51.8%) were made by hospitals or clinics and 94 sites (87.0%) were made for patients. Of the 108 sites, eleven web sites (10.1%) had more than three JAMA benchmarks (authorship, references, currency, and disclosure). Higher quality sites (at least three JAMA benchmarks) were less likely to contain inaccurate information than lower quality sites (fewer than three JAMA benchmarks)-3/11 (27.2%) vs. 60/97 (61.9%) (p<0.01). Despite the fact that articles in the literature emphasized an insufficient evidence to support an association between the lifestyle, dietary behaviors, and GERD, such guidelines continue to be recommended as first-line therapy in most websites. CONCLUSIONS: Informations about gastroesophageal reflux disease were incomplete in the majority of medical web sites. These would bring about confusion to patients seeking for an information about GERD through the internet. There is a need for better sources in evidence based informations about gastroesophageal reflux diseases on the web. 相似文献