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81.
Hong-Lim Kim Ji Hyun Jeon Tae-Hyung Koo U-Young Lee Eojin Jeong Myung-Hoon Chun Jung-Il Moon Stephen C. Massey In-Beom Kim 《PloS one》2012,7(12)
In the mammalian retina, bipolar cells and ganglion cells which stratify in sublamina a of the inner plexiform layer (IPL) show OFF responses to light stimuli while those that stratify in sublamina b show ON responses. This functional relationship between anatomy and physiology is a key principle of retinal organization. However, there are at least three types of retinal neurons, including intrinsically photosensitive retinal ganglion cells (ipRGCs) and dopaminergic amacrine cells, which violate this principle. These cell types have light-driven ON responses, but their dendrites mainly stratify in sublamina a of the IPL, the OFF sublayer. Recent anatomical studies suggested that certain ON cone bipolar cells make axonal or ectopic synapses as they descend through sublamina a, thus providing ON input to cells which stratify in the OFF sublayer. Using immunoelectron microscopy with 3-dimensional reconstruction, we have identified axonal synapses of ON cone bipolar cells in the rabbit retina. Ten calbindin ON cone bipolar axons made en passant ribbon synapses onto amacrine or ganglion dendrites in sublamina a of the IPL. Compared to the ribbon synapses made by bipolar terminals, these axonal ribbon synapses were characterized by a broad postsynaptic element that appeared as a monad and by the presence of multiple short synaptic ribbons. These findings confirm that certain ON cone bipolar cells can provide ON input to amacrine and ganglion cells whose dendrites stratify in the OFF sublayer via axonal synapses. The monadic synapse with multiple ribbons may be a diagnostic feature of the ON cone bipolar axonal synapse in sublamina a. The presence of multiple ribbons and a broad postsynaptic density suggest these structures may be very efficient synapses. We also identified axonal inputs to ipRGCs with the architecture described above. 相似文献
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Hyung Sun Kim Seho Park Ja Seung Koo Sanghwa Kim Jee Ye Kim Sanggeun Nam Hyung Seok Park Seung Il Kim Byeong-Woo Park 《PloS one》2016,11(3)
Purpose
The Ki-67 labelling index is significant for the management of breast cancer. However, the concordance of Ki-67 expression between preoperative biopsy and postoperative surgical specimens has not been well evaluated. This study aimed to find the correlation in Ki-67 expression between biopsy and surgical specimens and to determine the clinicopathological risk factors associated with discordant values.Patients and Methods
Ki-67 levels were immunohistochemically measured using paired biopsy and surgical specimens in 310 breast cancer patients between 2008 and 2013. ΔKi-67 was calculated by postoperative Ki-67 minus preoperative levels. The outliers of ΔKi-67 were defined as [lower quartile of ΔKi-67–1.5 × interquartile range (IQR)] or (upper quartile + 1.5 × IQR) and were evaluated according to clinicopathological parameters by logistic regression analysis.Results
The median preoperative and postoperative Ki-67 levels were 10 (IQR, 15) and 10 (IQR, 25), respectively. Correlation of Ki-67 levels between the two specimens indicated a moderately positive relationship (coefficient = 0.676). Of 310 patients, 44 (14.2%) showed outliers of ΔKi-67 (range, ≤-20 or ≥28). A significant association with poor prognostic factors was found among these patients. Multivariate analysis determined that significant risk factors for outliers of ΔKi-67 were tumor size >1 cm, negative progesterone receptor (PR) expression, grade III cancer, and age ≤35 years. Among 171 patients with luminal human epidermal growth factor receptor 2-negative tumors, breast cancer subtype according to preoperative or postoperative Ki-67 levels discordantly changed in 46 (26.9%) patients and a significant proportion of patients with discordant cases had ≥1 risk factor.Conclusion
Ki-67 expression showed a substantial concordance between biopsy and surgical specimens. Extremely discordant Ki-67 levels may be associated with aggressive tumor biology. In patients with luminal subtype disease, clinical application of Ki-67 values should be cautious considering types of specimens and clinicopathological risk factors. 相似文献85.
Sexual and somatic determinants of the human Y chromosome: studies in a 46,XYp- phenotypic female. 总被引:5,自引:0,他引:5 下载免费PDF全文
R G Rosenfeld L Luzzatti R L Hintz O J Miller G C Koo S S Wachtel 《American journal of human genetics》1979,31(4):458-468
A case of a 46,XYp- phenotypic female provided an opportunity to evaluate both sexual and somatic determinants for the Y chromosome. The patient had multiple stigmata of Turner syndrome, but normal stature. Laparotomy revealed a normal uterus and tubes, with 1.5 cm undifferentiated gonads. Serological tests for H-Y antigen (ostensibly the product of Y-chromosomal testis-determining genes) indicated absence of the H-Y+ phenotype normally associated with the intact Y chromosome. We conclude that genes exist on the short arm of the human Y chromosome which both suppress some of the somatic stigmata of Turner syndrome and determine normal expression of H-Y antigen and testicular differentiation of the primitive gonad. Our data are consistent with the view that H-Y genes comprise a family of testis-determinants, and that loss of a critical moiety is inconsistent with normal development of the male gonad. 相似文献
86.
Hyunseok Koo Bipinchandra K. Salunke Bilal Iskandarani Won-Gyun Oh Beom Soo Kim 《Biotechnology and Bioprocess Engineering》2017,22(5):597-603
The ability of Fe3O4 Fenton-like reaction to produce glucose from lignocellulosic biomass was investigated. Fe3O4 magnetite nanoparticles were chemically synthesized from iron salts (a mixture of 1 M FeCl2 and 2M FeCl3) using an ammonia solution (30% NH4OH). The synthesized Fe3O4 nanoparticles were further characterized by X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy. Reed stems and rice straw biomasses pretreated with optimized Fenton-like reagents (Fe3O4 and H2O2) increased glucose production by 177 and 87%, respectively, compared to the control without the catalysts. 相似文献
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Increasing evidence suggests that CD45, a transmembrane protein tyrosine phosphatase, is an important modulator of macrophage activation. Microglia, resident brain macrophages, express CD45 and proliferate under pathologic conditions. In this study, we examined the role of CD45 in modulating GM-CSF-induced proliferation and signal transduction in primary human microglial cultures. Soluble, but not immobilized anti-CD45RO induced tyrosine phosphatase activity and inhibited GM-CSF-induced microglial proliferation. Microglial proliferation was also inhibited by PP2 (Src inhibitor), LY294002 (PI3K inhibitor), and U0126 (MEK inhibitor). GM-CSF induced phosphorylation of Jak2, Stat5, Hck (the myeloid-restricted Src kinase), Akt, Stat3, and Erk MAPKs in microglia. Of these, anti-CD45RO inhibited phosphorylation of Hck and Akt, and PP2 inhibited phosphorylation of Hck and Akt. In a macrophage cell line stably overexpressing wild-type or kinase-inactive Hck, GM-CSF increased proliferation of the control (empty vector) and wild-type but not kinase-inactive cells, and this was inhibited by anti-CD45RO. Together, these results demonstrate that, in macrophages, Hck tyrosine kinase is activated by GM-CSF, and that Hck plays a pivotal role in cell proliferation and survival by activating the PI3K/Akt pathway. Ab-mediated activation of macrophage and microglial CD45 tyrosine phosphatase may have therapeutic implications for CNS inflammatory diseases. 相似文献
90.
The genetic diversity and population structures within and between Korean and Japanese populations of Salanx ariakensis were investigated using AFLP (amplified fragment length polymorphism). Using seven primer pair sets, 411 fragments were amplified
from 31 specimens of S. ariakensis, 393 fragments (96%) being polymorphic. The expected heterozygosities were 0.211 and 0.245 for the Japanese and Korean populations,
respectively, levels similar to those of other freshwater and diadromous fishes, but lower than those of marine fishes. The
difference in genetic diversity between the two populations may result from their different habitat sizes. Principal coordinate
analysis using 393 polymorphic fragments resulted in specimens from each population being plotted separated, suggesting an
absence (or little if present) gene flow between them since Tsushima Strait has been open. Therefore, each population of S. ariakensis is relevant from the conservation perspective and should at least be treated as a “management unit” for conservation purposes. 相似文献