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61.
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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
63.
Joungyoun Kim Yoon-Jong Bae Jae-woo Lee Ye-seul Kim Yonghwan Kim Hyo-Sun You Hyeong-Seop Kim Eun-A Choi Ye-Eun Han Hee-Taik Kang 《Medicine》2021,100(11)
Malignant neoplasms are the leading cause of death in Korea. We aimed to examine if metformin use in cancer survivors reduces all-cause mortality. This study was retrospectively designed based on data from the Korean National Health Insurance Service-National Health Screening Cohort (HEALS) between 2002 and 2015. The Kaplan–Meier estimator and log-rank test was performed to estimate the survival function according to metformin usage (3721 metformin non-users with diabetes, 5580 metformin users with diabetes, and 24,483 non-diabetic individuals). Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were calculated using Cox proportional hazards regression models.The median follow-up duration was 4.2 years. The HRs (95% CIs) for all-cause mortality of metformin users and the non-diabetic group were 0.762 (0.683–0.850) and 1.055 (0.966–1.152) in men and 0.805 (0.649–0.999), and 1.049 (0.873–1.260) in women, respectively, compared with metformin non-users among diabetic cancer survivors, in a fully adjusted model. After stratifying metformin users into pre- and post-diagnosis of cancers, adjusted HRs (95% CIs) of pre- and post-diagnosis metformin users for all-cause mortality were 0.948 (0.839–1.071) and 0.530 (0.452–0.621) in men and 1.163 (0.921–1.469) and 0.439 (0.323–0.596) in women, respectively.Metformin use in cancer survivors with diabetes reduced overall mortality rates. In particular, metformin use after cancer diagnosis, not before cancer diagnosis, was inversely associated with overall mortality.Active treatment with metformin for diabetic cancer survivors after cancer diagnosis can improve their survival rates. 相似文献
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66.
Ho-Jong Kim Daehee Kim Suyong Jung Myung-Ho Bae Sam Nyung Yi Kenji Watanabe Takashi Taniguchi Soo Kyung Chang Dong Han Ha 《RSC advances》2018,8(23):12900
We investigated the homogeneity and tolerance to heat of monolayer MoS2 using photoluminescence (PL) spectroscopy. For MoS2 on SiO2, the PL spectra of the basal plane differ from those of the edge, but MoS2 on hexagonal boron nitride (h-BN) was electron-depleted with a homogeneous PL spectra over the entire area. Annealing at 450 °C rendered MoS2 on SiO2 homogeneously electron-depleted over the entire area by creating numerous defects; moreover, annealing at 550 °C and subsequent laser irradiation on the MoS2 monolayer caused a loss of its inherent crystal structure. On the other hand, monolayer MoS2 on h-BN was preserved up to 550 °C with its PL spectra not much changed compared with MoS2 on SiO2. We performed an experiment to qualitatively compare the binding energies between various layers, and discuss the tolerance of monolayer MoS2 to heat on the basis of interlayer/interfacial binding energy.We investigated the homogeneity and tolerance to heat of monolayer MoS2 using photoluminescence (PL) spectroscopy. 相似文献
67.
So-Youn Kwon Ok-Nam Bae Ji-Yoon Noh Keunyoung Kim Seojin Kang Young-Jun Shin Kyung-Min Lim Jin-Ho Chung 《Environmental health perspectives》2015,123(2):120-127
Background: Nephrotoxicity associated with lead poisoning has been frequently reported in epidemiological studies, but the underlying mechanisms have not been fully described.Objectives: We examined the role of erythrocytes, one of the major lead reservoirs, in lead-associated nephrotoxicity.Methods and results: Co-incubation of lead-exposed human erythrocytes with HK-2 human renal proximal tubular cells resulted in renal tubular cytotoxicity, suggesting a role of erythrocytes in lead-induced nephrotoxicity. Morphological and flow cytometric analyses revealed that HK-2 cells actively phagocytized lead-exposed erythrocytes, which was associated with phosphatidylserine (PS) externalization on the erythrocyte membrane and generation of PS-bearing microvesicles. Increased oxidative stress and up-regulation of nephrotoxic biomarkers, such as NGAL, were observed in HK-2 cells undergoing erythrophagocytosis. Moreover, TGF-β, a marker of fibrosis, was also significantly up-regulated. We examined the significance of erythrophagocytosis in lead-induced nephrotoxicity in rats exposed to lead via drinking water for 12 weeks. We observed iron deposition and generation of oxidative stress in renal tissues of lead-exposed rats, as well as the histopathological alterations such as tubulointerstitial lesions, fibrosis, and up-regulation of KIM-1, NGAL, and TGF-β.Conclusions: Our data strongly suggest that erythrophagocytosis and subsequent iron deposition in renal tubular cells could significantly enhance nephrotoxicity following lead exposure, providing insight on lead-associated kidney damages.Citation: Kwon SY, Bae ON, Noh JY, Kim K, Kang S, Shin YJ, Lim KM, Chung JH. 2015. Erythrophagocytosis of lead-exposed erythrocytes by renal tubular cells: possible role in lead-induced nephrotoxicity. Environ Health Perspect 123:120–127; http://dx.doi.org/10.1289/ehp.1408094 相似文献
68.
Jin-Hwa Jang Ji-Hae Lee Mi-Kyung Je Myeong-Ji Cho Young Mee Bae Hyeon Seok Son Insung Ahn 《Yebang Ŭihakhoe chi》2015,48(4):203-215
Objectives:
This study was performed to investigate the relationship between the incidence of national notifiable infectious diseases (NNIDs) and meteorological factors, air pollution levels, and hospital resources in Korea.Methods:
We collected and stored 660 000 pieces of publicly available data associated with infectious diseases from public data portals and the Diseases Web Statistics System of Korea. We analyzed correlations between the monthly incidence of these diseases and monthly average temperatures and monthly average relative humidity, as well as vaccination rates, number of hospitals, and number of hospital beds by district in Seoul.Results:
Of the 34 NNIDs, malaria showed the most significant correlation with temperature (r=0.949, p<0.01) and concentration of nitrogen dioxide (r=-0.884, p<0.01). We also found a strong correlation between the incidence of NNIDs and the number of hospital beds in 25 districts in Seoul (r=0.606, p<0.01). In particular, Geumcheon-gu was found to have the lowest incidence rate of NNIDs and the highest number of hospital beds per patient.Conclusions:
In this study, we conducted a correlational analysis of public data from Korean government portals that can be used as parameters to forecast the spread of outbreaks. 相似文献69.
Seung Woo Kim Geun-Yong Kwon Bongyoung Kim Donghyok Kwon Jaeseung Shin Geun-Ryang Bae 《Osong Public Health and Research Perspectives》2015,6(6):363-368
Objectives
Melioidosis is a potentially fatal infectious disease caused by the environmental anaerobic Gram-negative bacillus Burkholderia pseudomallei. Melioidosis is endemic to areas of northern Australia and Southeast Asia. With increasing international travel and migration, imported cases of melioidosis are being reported regularly. Here, we summarize the 11 cases of melioidosis reported in South Korea from 2003 to 2014.Methods
Tracing epidemiological investigations were performed on every patient reported to the National Surveillance System since 2011. A systematic literature search was performed to identify melioidosis cases that occurred prior to 2011.Results
The overall fatality rate was 36.4%. All the patients had visited Southeast Asia where melioidosis is endemic. The stay in the endemic region ranged from 4 days to 20 years. Of the seven patients who developed initial symptoms after returning to South Korea, the time interval between returning to South Korea and symptom onset ranged from 1 day to 3 years. The remaining four patients developed symptoms during their stay in the endemic region and were diagnosed with melioidosis in South Korea. Seven (63.6%) patients possessed at least one risk factor, all of whom were diabetic. Pneumonia was the most frequent clinical manifestation, but the patients showed a wide spectrum of clinical features, including internal organ abscesses, a mycotic aneurysm of the aorta, and coinfection with tuberculosis.Conclusion
An early diagnosis and initiation of the appropriate antibiotics can reduce the mortality of melioidosis. Consequently, increased awareness of the risk factors and clinical features of melioidosis is required. 相似文献70.
Hye-Ryoung Kim Yong-Kuk Kwon Il Jang Youn-Jeong Lee Hyun-Mi Kang Eun-Kyoung Lee Byung-Min Song Hee-Soo Lee Yi-Seok Joo Kyung-Hyun Lee Hyun-Kyoung Lee Kang-Hyun Baek You-Chan Bae 《Emerging infectious diseases》2015,21(5):775-780
In January 2014, an outbreak of infection with highly pathogenic avian influenza (HPAI) A(H5N8) virus began on a duck farm in South Korea and spread to other poultry farms nearby. During this outbreak, many sick or dead wild birds were found around habitats frequented by migratory birds. To determine the causes of death, we examined 771 wild bird carcasses and identified HPAI A(H5N8) virus in 167. Gross and histologic lesions were observed in pancreas, lung, brain, and kidney of Baikal teals, bean geese, and whooper swans but not mallard ducks. Such lesions are consistent with lethal HPAI A(H5N8) virus infection. However, some HPAI-positive birds had died of gunshot wounds, peritonitis, or agrochemical poisoning rather than virus infection. These findings suggest that susceptibility to HPAI A(H5N8) virus varies among species of migratory birds and that asymptomatic migratory birds could be carriers of this virus. 相似文献