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91.
Jung Hyun Yoon Kyung Hwa Han Eun-Kyung Kim Hee Jung Moon Min Jung Kim Young Joo Suh Ji Soo Choi Byeong-Woo Park 《PloS one》2013,8(2)
Introduction
To assess whether the value of CYFRA21-1 in the aspirates of ultrasonography-guided fine-needle aspiration biopsy (US-FNAB) can contribute to improving the performances of US-FNAB in the diagnosis of axillary lymph node (LN) metastasis in breast cancer patients.Methods
US-FNAB was performed in 156 axillary LNs in 152 breast cancer patients (mean age: 51.4 years, range: 17–92 years). Concentrations of CYFRA21-1 were measured from washouts of the syringe used during US-FNAB. Tumor marker concentrations, US-FNAB, intraoperative sentinel node biopsy (SNB), and surgical pathology results were reviewed and analyzed. For comparison, the values of CEA and CA15-3 were also measured from washouts.Results
Among the 156 LNs, 75 (48.1%) were benign, and 81 (51.9%) were metastases. Mean concentrations of CYFRA21-1 were significantly higher in metastasis compared to benign LNs (P<0.001). US-FNAB combined to CYFRA21-1 showed significantly higher sensitivity, NPV, and accuracy compared to US-FNAB alone (all values P<0.05). All diagnostic indices of US-FNAB combined to CYFRA21-1 were significantly higher compared to US-FNAB combined with CEA or CA15-3 (all P<0.001). Of the 28 metastatic LNs which showed metastasis on SNB, CYFRA21-1 showed higher positive rate of 75.0% (CEA or CA15-3∶60.7%, P = 0.076).Conclusion
Measuring CYFRA 21-1 concentrations from US-FNAB aspirates improves sensitivity, NPV, and accuracy of US-FNAB alone, and may contribute to reducing up to 75.0% of unnecessary intraoperative SNB. Compared to CEA or CA15-3, CYFRA21-1 shows significantly higher performances when combined to US-FNAB in the preoperative diagnosis of LN metastasis in breast cancer patients. 相似文献92.
93.
94.
Lee Y Kim YW Jeon BW Park KY Suh SJ Seo J Kwak JM Martinoia E Hwang I Lee Y 《The Plant journal : for cell and molecular biology》2007,52(5):803-816
Previously, we demonstrated that a protein that binds phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P(2)] inhibits both light-induced stomatal opening and ABA-induced stomatal closing. The latter effect is due to a reduction in free PtdIns(4,5)P(2), decreasing production of inositol 1,4,5-trisphosphate and phosphatidic acid by phospholipases C and D. However, it is less clear how PtdIns(4,5)P(2) modulates stomatal opening. We found that in response to white light irradiation, the PtdIns(4,5)P(2)-binding domain GFP:PLCdelta1PH translocated from the cytosol into the plasma membrane. This suggests that the level of PtdIns(4,5)P(2) increases at the plasma membrane upon illumination. Exogenously administered PtdIns(4,5)P(2) substituted for light stimuli, inducing stomatal opening and swelling of guard cell protoplasts. To identify PtdIns(4,5)P(2) targets we performed patch-clamp experiments, and found that anion channel activity was inhibited by PtdIns(4,5)P(2). Genetic analyses using an Arabidopsis PIP5K4 mutant further supported the role of PtdIns(4,5)P(2) in stomatal opening. The reduced stomatal opening movements exhibited by a mutant of Arabidopsis PIP5K4 (At3g56960) was countered by exogenous application of PtdIns(4,5)P(2). The phenotype of reduced stomatal opening in the pip5k4 mutant was recovered in lines complemented with the full-length PIP5K4. Together, these data suggest that PIP5K4 produces PtdIns(4,5)P(2) in irradiated guard cells, inhibiting anion channels to allow full stomatal opening. 相似文献
95.
Objective
Young adulthood is an important period for both bone and mental health. This study investigated the association between depressive symptoms and bone density in apparently healthy Korean men and women aged 29−32 years.Methods
This study is a cross-sectional analysis of data from 123 men and 133 women who completed follow-up examinations of the Kangwha study in 2010−2011. Bone stiffness index (SI) was measured at the os calcis using a quantitative ultrasound device. Depressive symptoms were evaluated using the Korean version of the Beck Depression Inventory (K-BDI) and classified as normal (K-BDI <10), mild (K-BDI 10–15), and moderate to severe (K-BDI ≥16).Results
Moderate to severe depressive symptoms were prevalent among 11.4% of men and 19.6% of women. Higher K-BDI scores were significantly correlated to SI in men, before (ρ = –0.286, p = 0.001) and after (ρ = –0.228, p = 0.013) adjustment for covariates. Men with depressive symptoms tended to have a lower SI; multivariate-adjusted mean SI in men with normal, mild, and moderate to severe depressive symptoms was 104.1±3.1, 100.9±5.9, and 94.1±7.8, respectively (p for trend = 0.021). In contrast, no significant correlations were identified in women.Conclusions
Depressive symptoms were significantly associated with lower SI in men, but not in women. Further studies are necessary to evaluate the impact of depression on developing osteoporosis or osteoporotic fractures later in life. 相似文献96.
Sensory systems must be able to extract features of a stimulus to detect and represent properties of the world. Because sensory signals are constantly changing, a critical aspect of this transformation relates to the timing of signals and the ability to filter those signals to select dynamic properties, such as visual motion. At first assessment, one might think that the primary biophysical properties that construct a temporal filter would be dynamic mechanisms such as molecular concentration or membrane electrical properties. However, in the current issue of PLOS Biology, Baden et al. identify a mechanism of temporal filtering in the zebrafish and goldfish retina that is not dynamic but is in fact a structural building block—the physical size of a synapse itself. The authors observe that small, bipolar cell synaptic terminals are fast and highly adaptive, whereas large ones are slower and adapt less. Using a computational model, they conclude that the volume of the synaptic terminal influences the calcium concentration and the number of available vesicles. These results indicate that the size of the presynaptic terminal is an independent control for the dynamics of a synapse and may reveal aspects of synaptic function that can be inferred from anatomical structure. 相似文献
97.
Cloning and characterization of chalcone synthase from the moss, Physcomitrella patens 总被引:3,自引:0,他引:3
Since the early evolution of land plants from primitive green algae, flavonoids have played an important role as UV protective pigments in plants. Flavonoids occur in liverworts and mosses, and the first committed step in the flavonoid biosynthesis is catalyzed by chalcone synthase (CHS). Although higher plant CHSs have been extensively studied, little information is available on the enzymes from bryophytes. Here we report the cloning and characterization of CHS from the moss, Physcomitrella patens. Taking advantage of the available P. patens EST sequences, a CHS (PpCHS) was cloned from the gametophores of P. patens, and heterologously expressed in Escherichia coli. PpCHS exhibited similar kinetic properties and substrate preference profile to those of higher plant CHS. p-Coumaroyl-CoA was the most preferred substrate, suggesting that PpCHS is a naringenin chalcone producing CHS. Consistent with the evolutionary position of the moss, phylogenetic analysis placed PpCHS at the base of the plant CHS clade, next to the microorganism CHS-like gene products. Therefore, PpCHS likely represents a modern day version of one of the oldest CHSs that appeared on earth. Further, sequence analysis of the P. patens EST and genome databases revealed the presence of a CHS multigene family in the moss as well as the 3'-end heterogeneity of a CHS gene. Of the 19 putative CHS genes, 10 genes are expressed and have corresponding ESTs in the databases. A possibility of the functional divergence of the multiple CHS genes in the moss is discussed. 相似文献
98.
99.
Lack of antinociceptive cross-tolerance between intracerebroventricularly administered beta-endorphin and morphine or DPDPE in mice 总被引:1,自引:0,他引:1
Antinociceptive tolerance and cross-tolerance to intracerebroventricular (i.c.v.) beta-endorphin, morphine, and DPDPE (D-Pen2-D-Pen5-enkephalin) induced by a prior i.c.v. administration of beta-endorphin, morphine and DPDPE, respectively, were studied in mice. Acute tolerance was induced by i.c.v. pretreatment with beta-endorphin (0.58 nmol), morphine (6 nmol) and DPDPE (31 nmol) for 120, 180 and 75 min, respectively. Various doses of beta-endorphin, morphine or DPDPE were then injected. The tail-flick and hot-plate tests were used as antinociceptive tests. Pretreatment of mice with beta-endorphin i.c.v. reduced inhibition of the tail-flick and hot-plate responses to i.c.v. administered beta-endorphin, but not morphine and DPDPE. Pretreatment of mice with morphine i.c.v. reduced inhibition of the tail-flick and hot-plate responses to morphine but not beta-endorphin. Pretreatment of mice with DPDPE reduced inhibition of the tail-flick and hot-plate responses to DPDPE but not beta-endorphin. The results indicate that one injection of beta-endorphin, morphine or DPDPE induces acute antinociceptive tolerance to its own distinctive opioid receptor and does not induce cross-tolerance to other opioid agonists with different opioid receptor specificities. The data support the hypothesis that beta-endorphin, morphine and DPDPE produce antinociception by stimulating specific epsilon, mu- and delta-opioid receptors, respectively. 相似文献
100.
Hyun-Ok Song Je-Hyoung Kim Ho-Sun Ryu Dong-Hoon Lee Sun-Jin Kim Deog-Joong Kim In Bum Suh Du Young Choi Kwang-Ho In Sung-Woo Kim Hyun Park 《PloS one》2012,7(12)
It is clinically important to be able to detect influenza A/H1N1 virus using a fast, portable, and accurate system that has high specificity and sensitivity. To achieve this goal, it is necessary to develop a highly specific primer set that recognizes only influenza A viral genes and a rapid real-time PCR system that can detect even a single copy of the viral gene. In this study, we developed and validated a novel fluidic chip-type real-time PCR (LabChip real-time PCR) system that is sensitive and specific for the detection of influenza A/H1N1, including the pandemic influenza strain A/H1N1 of 2009. This LabChip real-time PCR system has several remarkable features: (1) It allows rapid quantitative analysis, requiring only 15 min to perform 30 cycles of real-time PCR. (2) It is portable, with a weight of only 5.5 kg. (3) The reaction cost is low, since it uses disposable plastic chips. (4) Its high efficiency is equivalent to that of commercially available tube-type real-time PCR systems. The developed disposable LabChip is an economic, heat-transferable, light-transparent, and easy-to-fabricate polymeric chip compared to conventional silicon- or glass-based labchip. In addition, our LabChip has large surface-to-volume ratios in micro channels that are required for overcoming time consumed for temperature control during real-time PCR. The efficiency of the LabChip real-time PCR system was confirmed using novel primer sets specifically targeted to the hemagglutinin (HA) gene of influenza A/H1N1 and clinical specimens. Eighty-five human clinical swab samples were tested using the LabChip real-time PCR. The results demonstrated 100% sensitivity and specificity, showing 72 positive and 13 negative cases. These results were identical to those from a tube-type real-time PCR system. This indicates that the novel LabChip real-time PCR may be an ultra-fast, quantitative, point-of-care-potential diagnostic tool for influenza A/H1N1 with a high sensitivity and specificity. 相似文献