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991.
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992.
Induction of MiR-21 by Stereotactic Body Radiotherapy Contributes to the Pulmonary Fibrotic Response
Ok-Seon Kwon Keun-Tae Kim Eunioo Lee Myoungjae Kim Seo-Hyun Choi Henghong Li Albert J. Fornace Jr. Jae-Ho Cho Yun-Sil Lee Ji-Seon Lee Yoon-Jin Lee Hyuk-Jin Cha 《PloS one》2016,11(5)
Radiation-induced lung fibrosis, the most serious effect of lung cancer radiotherapy on normal tissue, remains a major technical obstacle to the broader application of radiotherapy to patients with lung cancer. This study describes the use of an image-guided irradiation system in mice mimicking stereotactic body radiotherapy (SBRT) to examine the molecular features of chronic fibrotic response after radiation injury. MicroRNA (miR) array analysis of injured pulmonary tissue identified a set of miRs whose expression was significantly increased in damaged lung tissue. In particular, miR-21 expression was increased at the radiation injury site, concurrent with collagen deposition. Although the inhibition of miR-21 by its specific inhibitor anti-miR-21 only marginally affected endothelial-mesenchymal transition (EndMT) in lung endothelial cells, this inhibition significantly reduced collagen synthesis in lung fibroblasts. Furthermore, ectopic expression of miR-21 was sufficient to promote a fibrotic response in lung fibroblasts, enhancing Smad2 phosphorylation concurrent with Smad7 downregulation. These findings indicate that the induction of miR-21 expression is responsible for fibrotic responses observed in mesenchymal cells at the injury site through the potentiation of TGF-β signaling. Local targeting of miR-21 at the injured area could have potential therapeutic utility in mitigating radiation-induced lung fibrosis. 相似文献
993.
Purpose
To compare the reproducibility of SD-OCT (spectral-domain optical coherence tomography) measurements of RNFL (retinal nerve fiber layer) and macular thickness between children and adults.Methods
Seventy-one eyes of 71 children and 71 eyes of 71 adults were prospectively enrolled. RNFL and macular thicknesses were measured by one operator, with a brief rest between measurements. The two measurements were obtained using the eye tracking and retest function of Spectralis SD-OCT. Reproducibility was evaluated with reference to COVs (coefficients of variation) and ICCs (intraclass correlation coefficients). The ICC values of the RNFL and macular thicknesses were compared, respectively between the two groups, by Fisher’s z-test.Results
The RNFL and macular thicknesses did not differ between the two groups. The COVs of the RNFL measurements ranged from 0.945 to 4.531% in the children group and from 0.496 to 1.391% in the adults group. In most of the RNFL sectors, the ICCs of the children group (range: 0.731–0.987) were significantly lower than those of the adults group (range: 0.986–0.993). The COVs of the macular measurements ranged from 0.496 to 1.157% in the children group and from 0.275 to 0.656% in the adults group. The ICCs (range: 0.860–0.974) in the children group, significantly lower than for the adults (range: 0.989–0.995), in all of the macular sectors.Conclusions
The reproducibility of SD-OCT RNFL and macular measurements for children was excellent, albeit statistically lower than that for adults. 相似文献994.
Hallucinations and delusions are the most prominent symptoms of schizophrenia and characterized by impaired reality testing. Representation-mediated taste aversion (RMTA) has been proposed as a potential behavioral assessment of reality testing and has been applied to a neurodevelopmental rat model of schizophrenia. However, the theory underlying this approach has not been generalized yet with any demonstration of impaired reality testing in other animal models of schizophrenia, such as genetically-modified mice. We devised a RMTA procedure for mice that combines a Pavlovian association protocol pairing odor conditioned stimulus (CS) with sugar reward unconditioned stimulus (US), and a conditioned taste aversion (CTA) method. In this RMTA paradigm, we compared performances of wild-type (PLCβ1+/+) mice and phospholipase C β1 knock-out (PLCβ1-/-) mice which are known as one of the genetic models for schizophrenia. With a minimal amount of initial odor-sugar associative training, both PLCβ1+/+ and PLCβ1-/- mice were able to form an aversion to the sugar reward when the odor CS predicting sugar was paired with nausea. With an extended initial training, however, only PLCβ1-/- mice could form a RMTA. This persistent RMTA displayed by PLCβ1-/- mice shows their inability to distinguish real sugar from the CS-evoked representation of sugar at a stage in associative learning where wild-type mice normally could differentiate the two. These results demonstrate an impaired reality testing first observed in a genetic mouse model of schizophrenia, and suggest that RMTA paradigm may, with general applicability, allow diverse biological approaches to impaired reality testing. 相似文献
995.
996.
Sun Hee Lee Inhwan Lee Min Hwan Kim Ji Su Go Sang Ho Lee Hye Jin Hwang 《Animal cells and systems.》2016,20(6):353-362
An extract of Ulmus macrocarpa Hance, commonly known as the large-fruited elm, has been prescribed as a traditional medicine. In this study, we aimed to investigate the cellular immune effects of U. macrocarpa stem cortex extracts on cyclophosphamide (CY)-treated splenocytes and mice. A methanol extract showed an improved survival rate of splenocytes after 72?h. The extract was successively partitioned with dichloromethane, ethyl acetate, n-butanol, and water; and the fractions so obtained were also examined for their proliferative activity. Among them, the water fraction of U. macrocarpa showed the highest proliferation of splenocytes and was used throughout the present study. We tested the survival rate of splenocytes through dose-dependent treatment of CY and the suppression of the survival effect by CY was recovered by treatment with the water extract of U. macrocarpa. To determine the mechanism involved, we examined the expression of B-cell lymphoma-extra large (Bcl-xL) anti-apoptotic protein. CY decreased Bcl-xL protein levels in resting splenocyte cultures, whereas splenocytes were exposed to water extracts of U. macrocarpa in the presence of CY; however, elevations in Bcl-xL were observed at 96?h. Mice splenocytes treated with water extract of U. macrocarpa for cellular immunity showed an increase in the activity of the mixed lymphocyte reaction (MLR), cytotoxic T lymphocytes (CTLs), and natural killer (NK) cells. In addition, mice receiving a water extract of U. macrocarpa recovered the CTL, NK, and MLR activities suppressed by CY administration. Consequently, U. macrocarpa improves the cell-mediated immune response and provides an insight on cell-based tonic materials. 相似文献
997.
Apolipoprotein C3 (ApoC3) plays a regulatory role in triglyceride (TG) metabolism. The higher level of TG can be a cause in pathogenesis of the vascular diseases or metabolic syndrome (MetS). In this study, we examined the associations of ApoC3 polymorphisms (?482C>T rs2854117 and 3238G>C rs5128) with Korean MetS patients. A total of 835 subjects were investigated, including 320 patients with MetS and 515 healthy subjects. The genotype analysis of the ApoC3 polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism methods. Of the two polymorphisms studied, we observed a significant difference in the ?482C>T polymorphism between the MetS and control groups. The TT genotype of the ?482C>T polymorphism was associated with increased risk for MetS, compared with the controls (OR 1.627, 95 % CI 1.075–2.463, P = 0.021). The association was female-specific. No associations were found for the risk of MetS in the 3238G>C polymorphism. Haplotypes composed of two polymorphisms, however, were associated with MetS susceptibility in only male group. The 3238G>C polymorphism was significantly associated with TG levels (P = 0.013). Our data suggest that the ApoC3 ?482C>T polymorphism is associated with increased MetS susceptibility in the Korean population. 相似文献
998.
HyunSuk Jang Joohwan Yoon HyunJi Gil Sharon Jiyoon Jung Min-Suk Kim Jin-Kyu Lee Young-Jae Kim Kwang-Sup Soh 《PloS one》2016,11(3)
The primo vascular system (PVS) is being established as a circulatory system that corresponds to acupuncture meridians. There have been two critical questions in making the PVS accepted as a novel liquid flowing system. The first one was directly to show the flow of liquid in PVS and the second one was to explain why it was not observed in the conventional histological study of animal tissues. Flow in the PVS in the abdominal cavity was previously verified by injecting Alcian blue into a primo node. However, the tracing of the dye to other subsystems of the PVS has not been done. In the current work we injected fluorescent nanoparticles (FNPs) into a primo node and traced them along a primo vessel which was inside a fat tissue in the abdominal wall. Linea alba is a white middle line in the abdominal skin of a mammal and a band of fat tissue is located in parallel to the linea alba in the parietal side of the abdominal wall of a rat. In this fat band a primo vessel runs parallel to the prominent blood vessels in the fat band and is located just inside the parietal peritoneum. About the second question on the reason why the PVS was not in conventional histological study the current work provided the answer. Histological analysis with hematoxyline and eosine, Masson’s trichrome, and Toluidine blue could not discriminate the primo vessel even when we knew the location of the PVS by the trace of the FNPs. This clearly explains why the PVS is hard to observe in conventional histology: it is not a matter of resolution but the contrast. The PVS has very similar structure to the connective tissues that surround the PVS. In the current work we propose a method to find the PVS: Observation of mast cell distribution with toluidine blue staining and the PN has a high density of mast cells, while the lymph node has low density. 相似文献
999.
PurposeTo analyze the clinical features and prognostic factors associated with the survival of patients with a very rare occurrence of brain metastasis (BM) from differentiated thyroid cancer (DTC).ResultsThe median age at BM was 63 years, and the median time from initial thyroid cancer diagnosis to BM was 3.8 years. The median survival and the 1-year actuarial survival rate after BM were 8.8 months and 47%, respectively. According to univariate and multivariate analyses, four good prognostic factors (GPFs) were identified including age ≤ 60 years, PS ≤ ECOG 2, ≤ 3 BM sites, and without extracranial metastasis prior to BM. Three prognostic groups were designed based on age and number of remaining GPFs: patients ≤ 60 years of age with at least 2 GPFs (Group A) had the most favorable prognosis with a median survival of 32.8 months; patients ≤ 60 years of age with fewer than 2 GPFs and those > 60 years of age with at least 2 GPFs (Group B) had an intermediate prognosis with a median survival of 9.4 months; and patients > 60 years of age with fewer than 2 GPFs (Group C) had the least favorable prognosis with a median survival of 1.5 months.ConclusionsThe survival of patients with BM form DTC differed among the prognostic groups based on the total number of good prognostic factors. 相似文献
1000.
Suhrid Banskota Jaya Gautam Sushil C. Regmi Pallavi Gurung Myo-Hyeon Park Seung Joo Kim Tae-gyu Nam Byeong-Seon Jeong Jung-Ae Kim 《PloS one》2016,11(1)
5-Hydroxytryptamine (5-HT) induces proliferation of cancer cells and vascular cells. In addition to 5-HT production by several cancer cells including gastrointestinal and breast cancer, a significant level of 5-HT is released from activated platelets in the thrombotic environment of tumors, suggesting that inhibition of 5-HT signaling may constitute a new target for antiangiogenic anticancer drug discovery. In the current study we clearly demonstrate that 5-HT-induced angiogenesis was mediated through the 5-HT1 receptor-linked Gβγ/Src/PI3K pathway, but not through the MAPK/ERK/p38 pathway. In addition, 5-HT induced production of NADPH oxidase (NOX)-derived reactive oxygen species (ROS). In an effort to develop new molecularly targeted anticancer agents against 5-HT action in tumor growth, we demonstrate that BJ-1108, a derivative of 6-amino-2,4,5-trimethylpyridin-3-ol, significantly inhibited 5-HT-induced angiogenesis. In addition, BJ-1108 induced a significant reduction in the size and weight of excised tumors in breast cancer cell-inoculated CAM assay, showing proportionate suppression of tumor growth along with inhibition of angiogenesis. In human umbilical vein endothelial cells (HUVECs), BJ-1108 significantly suppressed 5-HT-induced ROS generation and phosphorylation of PI3K/Akt but not of Src. Unlike NOX inhibitors, BJ-1108, which showed better antioxidant activity than vitamin C, barely suppressed superoxide anion induced by mevalonate or geranylgeranyl pyrophosphate which directly activates NOX without help from other signaling molecules in HUVECs, implying that the anti-angiogenic action of BJ-1108 was not mediated through direct action on NOX activation, or free radical scavenging activity. In conclusion, BJ-1108 inhibited 5-HT-induced angiogenesis through PI3K/NOX signaling but not through Src, ERK, or p38. 相似文献