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Surgical Treatment of Ten Adults with Spinal Extradural Meningeal Cysts in the Thoracolumbar Spine

  • Xu, Feifan;Jian, Fengzeng;Li, Liang;Guan, Jian;Chen, Zan
    • Journal of Korean Neurosurgical Society
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    • v.64 no.2
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    • pp.238-246
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    • 2021
  • Objective : To retrospectively analyze the clinical characteristics and surgical experience of 10 adults with spinal extradural meningeal cysts (SEMCs) in the thoracolumbar spine which may further provide evidence for surgical decision-making. Methods : Ten adults with SEMCs in the thoracolumbar spine were surgically treated and enrolled in this study. Clinical manifestations, imaging data, intraoperative findings and postoperative outcome were recorded. Results : Clinical manifestations of SEMCs included motor and sensory dysfunction of the lower limbs and urination and defecation disturbance. The cysts presented as intraspinal occupying lesions dorsal to the spine, ranging from the T8 to L3 level. Defects of eight cases were found on preoperative magnetic resonance imaging (MRI). Selective hemilaminectomy or laminectomy were used to reveal the defect within the cyst, which was further sutured with microscopic technique. The final outcome was excellent or good in seven cases and fair in three cases. No recurrence was observed during follow-up. Conclusion : SEMCs are rare intraspinal cystic lesions. Radiography and MRI are clinically practical methods to assess defects within SEMCs. Selective hemilaminectomy or laminectomy may reduce surgical trauma. Detection and microscopic suturing of the defects are the key steps to adequately decompress the nervous tissue and prevent postoperative recurrence.

Implementation and benchmarking of the local weight window generation function for OpenMC

  • Hu, Yuan;Yan, Sha;Qiu, Yuefeng
    • Nuclear Engineering and Technology
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    • v.54 no.10
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    • pp.3803-3810
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    • 2022
  • OpenMC is a community-driven open-source Monte Carlo neutron and photon transport simulation code. The Weight Window Mesh (WWM) function and an automatic Global Variance Reduction (GVR) method was recently developed and implemented in a developmental branch of OpenMC. This WWM function and GVR method broaden OpenMC's usage in general purposes deep penetration shielding calculations. However, the Local Variance Reduction (LVR) method, which suits the source-detector problem, is still missing in OpenMC. In this work, the Weight Window Generator (WWG) function has been developed and benchmarked for the same branch. This WWG function allows OpenMC to generate the WWM for the source-detector problem on its own. Single-material cases with varying shielding and sources were used to benchmark the WWG function and investigate how to set up the particle histories utilized in WWG-run and WWM-run. Results show that there is a maximum improvement of WWM generated by WWG. Based on the above results, instructions on determining the particle histories utilized in WWG-run and WWM-run for optimal computation efficiency are given and tested with a few multi-material cases. These benchmarks demonstrate the ability of the OpenMC WWG function and the above instructions for the source-detector problem. This developmental branch will be released and merged into the main distribution in the future.

Kennicutt-Schmidt law with H I velocity profile decomposition in NGC 6822

  • Park, Hye-Jin;Oh, Se-Heon;Wang, Jing;Zheng, Yun;Zhang, Hong-Xin;de Blok, W.J.G.
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.1
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    • pp.32.3-33
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    • 2021
  • We present H I gas kinematics and star formation activities of NGC 6822, a dwarf galaxy located in the Local Volume at a distance of ~ 490 kpc. We perform profile decomposition of the line-of-sight velocity profiles of the high-resolution (42.4" × 12" spatial; 1.6 km/s spectral) H I data cube taken with the Australia Telescope Compact Array (ATCA). For this, we use a new tool, the so-called BAYGAUD (BAYesian GAUssian Decompositor) which is based on Bayesian Markov Chain Monte Carlo (MCMC) techniques, allowing us to decompose a line-of-sight velocity profile into an optimal number of Gaussian components in a quantitative manner. We classify the decomposed H I gas components of NGC 6822 into bulk-narrow, bulk-broad, and non_bulk with respect to their velocity and velocity dispersion. We correlate their gas surface densities with the surface star formation rates derived using both GALEX far-ultraviolet and WISE 22 micron data to examine the impact of gas turbulence caused by stellar feedback on the Kennicutt-Schmidt (K-S) law. The bulk-narrow component that resides within r25 is likely to follow the linear extension of the Kennicutt-Schmidt (K-S) law for molecular hydrogen (H2) at the low gas surface density regime where H I is not saturated.

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Gas dynamics and star formation in dwarf galaxies: the case of DDO 210

  • Oh, Se-Heon;Zheng, Yun;Wang, Jing
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.75.4-75.4
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    • 2019
  • We present a quantitative analysis of the relationship between the gas dynamics and star formation history of DDO 210 which is an irregular dwarf galaxy in the local Universe. We perform profile analysis of an high-resolution neutral hydrogen (HI) data cube of the galaxy taken with the large Very Large Array (VLA) survey, LITTLE THINGS using newly developed algorithm based on a Bayesian Markov Chain Monte Carlo (MCMC) technique. The complex HI structure and kinematics of the galaxy are decomposed into multiple kinematic components in a quantitative way like 1) bulk motions which are most likely to follow the underlying circular rotation of the disk, 2) non-circular motions deviating from the bulk motions, and 3) kinematically cold and warm components with narrower and wider velocity dispersion. The decomposed kinematic components are then spatially correlated with the distribution of stellar populations obtained from the color-magnitude diagram (CMD) fitting method. The cold and warm gas components show negative and positive correlations between their velocity dispersions and the surface star formation rates of the populations with ages of < 40 Myr and 100~400 Myr, respectively. The cold gas is most likely to be associated with the young stellar populations. Then the stellar feedback of the young populations could influence the warm gas. The age difference between the populations which show the correlations indicates the time delay of the stellar feedback.

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Combined Expression of Metastasis Related Markers Naa10p, SNCG and PRL-3 and its Prognostic Value in Breast Cancer Patients

  • Min, Li;Ma, Ruo-Lan;Yuan, Hua;Liu, Cai-Yun;Dong, Bing;Zhang, Cheng;Zeng, Yan;Wang, Li;Guo, Jian-Ping;Qu, Li-Ke;Shou, Cheng-Chao
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.2819-2826
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    • 2015
  • Combinations of multiple biomarkers representing distinct aspects of metastasis may have better prognostic value for breast cancer patients, especially those in late stages. In this study, we evaluated the protein levels of N-${\alpha}$-acetyltransferase 10 protein (Naa10p), synuclein-${\gamma}$ (SNCG), and phosphatase of regenerating liver-3 (PRL-3) in 365 patients with breast cancer by immunohistochemistry. Distinct prognostic subgroups of breast cancer were identified by combination of the three biomarkers. The Naa10p+SNCG-PRL-3-subgroup showed best prognosis with a median distant metastasis-free survival (DMFS) of 140 months, while the Naa10p-SNCG+PRL-3+subgroup had the worst prognosis with a median DMFS of 60.5 months. Multivariate analysis indicated Naa10p, SNCG, PRL-3, and the TNM classification were all independent prognostic factors for both DMFS and overall survival (OS). The three biomarker combination of Naa10p, SNCG and PRL-3 performed better in patients with lymph node metastasis, especially those with more advanced tumors than other subgroups. In conclusion, the combined expression profile of Naa10p, SNCG and PRL-3, alone or in combination with the TNM classification system, may provide a precise estimate of prognosis of breast cancer patients.

The BRAFT1799A Mutation is not Associated with Occult Contralateral Carcinoma in Patients with Unilateral Papillary Thyroid Microcarcinoma

  • Wan, Han-Feng;Zhang, Bin;Yan, Dan-Gui;Xu, Zhen-Gang
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.2947-2951
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    • 2015
  • Background: The phenomenon of occult carcinoma maybe observed in patients with clinically unilateral papillary thyroid microcarcinoma (PTMC). Although many studies have reported that the $BRAF^{T1799A}$ mutation is associated with aggressive PTMC, the relationship between $BRAF^{T1799A}$ mutation and occult carcinoma is unclear. The aim of this study was to investigate the risk factors, including $BRAF^{T1799A}$ mutation, for occult contralateral carcinoma in clinically unilateral PTMC accompanied by benign nodules in the contralateral lobe. Materials and Methods: From January 2011 to December 2013, we prospectively enrolled 89 consecutive PTMC patients with clinically unilateral carcinoma accompanied by benign nodules in the contralateral lobe who received a total thyroidectomy and cervical lymph node dissection. $BRAF^{T1799A}$ mutation was tested by pyrosequencing on postoperative paraffin specimens. The frequency and predictive factors for occult contralateral carcinoma were analyzed with respect to the following variables: age, gender, family history, tumor size, presence of Hashimoto thyroiditis, extrathyroidal extension, central lymph node metastasis, multifocality of primary tumor, or $BRAF^{T1799A}$ mutation. Results: A total of 36 patients (40.4%) had occult PTMC in the contralateral lobe. The median diameter of the occult tumors was $0.33{\pm}0.21cm$. The $BRAF^{T1799A}$ mutation was found in 38 cases (42.7%). According to the univariate analysis, there were no significant differences between the presence of occult contralateral carcinoma and age, gender, family history, tumor size, presence of Hashimoto thyroiditis, extrathyroidal extension, central lymph node metastasis, multifocality of primary tumor, or $BRAF^{T1799A}$ mutation. Conclusions: Using current methods, it is difficult to preoperatively identify patients with PTMC, and further research is needed to determine predictive factors for the presence of occult contralateral carcinoma in patients with unilateral PTMC.

Overexpression of Phospholipase A2 Group IIA in Esophageal Squamous Cell Carcinoma and Association with Cyclooxygenase-2 Expression

  • Zhai, Yan-Chun;Dong, Bin;Wei, Wen-Qiang;He, Yan;Li, Xin-Qing;Cormier, Robert T.;Wang, Wei;Liu, Fen
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9417-9421
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    • 2014
  • Background: Esophageal cancer is one of the most frequently occurring malignancies and the seventh leading cause of cancer-related deaths in the world. The esophageal squamous cell carcinoma (ESCC) is the most common histological type of esophageal cancer worldwide. Materials and Methods: Our goal in this study was to detect phospholipase A2 Group IIA (PLA2G2A) and cyclooxygenase-2 (COX-2) immuno-expression in ESCC in a high-risk population in China. Results: Positive expression of PLA2G2A protein was observed in 57.2% (166/290) of the cases, while COX-2 was found in 257 of 290 samples (88.6%), both PLA2G2A and COX-2 being expressed in 153 cases (52.8%), with a significant agreement (Kappa=0.091, p=0.031).Overexpression of PLA2G2A was significantly correlated with the depth of invasion (p=0.001). Co-expression of PLA2G2A and COX-2 not only significantly correlated with the depth of invasion (p=0.004) but also with TNM stage (p=0.04). Conclusions: Our results showed that in patients with ESCC, PLA2G2A overexpression and PLA2G2A co-expression with COX-2 is significantly correlated with advanced stage. The biological role and pathophysiologic regulation of PLA2G2A and COX-2 overexpression in ESCC deserve further investigation.

The culture conditions for mycelial growth and sclerotial formation of Polyporus umbellatus

  • Lee, Min Woong;Chang, Kwang Chun;Shin, Do Bin;Lee, Kyung Rim;Im, Kyung Hoan;Jin, Ga-Heon;Shin, Pyung Gyun;Xing, Yong Mei;Chen, Juan;Guo, Shun Xing;Lee, Tae Soo
    • Journal of Mushroom
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    • v.11 no.4
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    • pp.194-200
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    • 2013
  • Polyporus umbellatus (Syn. Grifola umbellata) is a sclerotium forming mushroom belongs to family Polyporaceae of Polyphorales, Basidiomycota. The sclerotia of P. umbellatus have long been used for traditional medicines in China, Korea and Japan. This study was initiated to obtain the basic data for artificial sclerotial production of P. umbellatus. Here, we investigated the favorable conditions for mycelial growth of P. umbellatus and its symbiotic fungus Armillaria mellea. We also evaluate the favorable carbon and nitrogen sources for sclerotial formation in dual culture between P. umbellatus and A. mellea. The favorable conditions for mycelial growth of P. umbellatus were $20^{\circ}C$ and pH 4, while optimal conditions for mycelial growth of A. mellea were $25^{\circ}C$ and pH 6. The carbon sources for optimal mycelial growth of P. umbellatus were fructose and glucose, while carbon sources for favorable mycelial growth of A. mellea were also fructose and glucose. The nitrogen sources for favorable mycelial growth P. umbellatus were peptone and yeast extract, while optimal mycelial growth of A. mellea were obtained in peptone and yeast extract. When P. umbellatus and A. mellea were dual cultured on carbon sources, sclerotia were induced on basal media supplemented with glucose, fructose and maltose at pH 4~6, while nitrogen sources inducing sclerotia were basal media supplemented with peptone and yeast extract for 60 days at $20^{\circ}C$ under dark condition.

Myeloid-Derived Suppressor Cells Are Associated with Viral Persistence and Downregulation of TCR ζ Chain Expression on CD8+ T Cells in Chronic Hepatitis C Patients

  • Zeng, Qing-Lei;Yang, Bin;Sun, Hong-Qi;Feng, Guo-Hua;Jin, Lei;Zou, Zheng-Sheng;Zhang, Zheng;Zhang, Ji-Yuan;Wang, Fu-Sheng
    • Molecules and Cells
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    • v.37 no.1
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    • pp.66-73
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    • 2014
  • Myeloid-derived suppressor cells (MDSCs) play an important role in impairing the function of T cells. We characterized MDSCs in two chronic hepatitis C (CHC) cohorts: a cross-sectional group that included 61 treatment-naive patients with CHC, 14 rapid virologic response (RVR) cases and 22 early virologic response (EVR) cases; and a longitudinal group of 13 cases of RVR and 10 cases of EVR after pegylated-interferon-${\alpha}$/ribavirin treatment for genotype 1b HCV infection. Liver samples from 32 CHC patients and six healthy controls were subjected to immunohistochemical analysis. MDSCs frequency in treatment-naive CHC was significantly higher than in RVR, EVR, or healthy subjects and was positively correlated with HCV RNA. Patients infected with HCV genotype 2a had a significantly higher frequency of MDSCs than those infected with genotype 1b. Decreased T cell receptor (TCR) ${\zeta}$ expression on $CD8^+$ T cells was significantly associated with an increased frequency of MDSCs in treatment-naive CHC patients and was restored by L-arginine treatment in vitro. Increased numbers of liver arginase-$1^+$ cells were closely associated with the histological activity index in CHC. The TCR ${\zeta}$ chain was significantly downregulated on hepatic $CD8^+$ T cells in CHC. During antiviral follow up, MDSCs frequency in peripheral blood mononuclear cells was directly correlated with the HCV RNA load in the plasma and inversely correlated with TCR ${\zeta}$ chain expression in $CD8^+$ T cells in both RVR and EVR cases. Notably, the RVR group had a higher frequency of MDSCs at baseline than the EVR group. Collectively, this study provides evidence that MDSCs might be associated with HCV persistence and downregulation of CD8 ${\zeta}$ chain expression.

Prevalence of Decreased Myocardial Blood Flow in Symptomatic Patients with Patent Coronary Stents: Insights from Low-Dose Dynamic CT Myocardial Perfusion Imaging

  • Yuehua Li;Mingyuan Yuan;Mengmeng Yu;Zhigang Lu;Chengxing Shen;Yining Wang;Bin Lu;Jiayin Zhang
    • Korean Journal of Radiology
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    • v.20 no.4
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    • pp.621-630
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    • 2019
  • Objective: To study the prevalence and clinical characteristics of decreased myocardial blood flow (MBF) quantified by dynamic computed tomography (CT) myocardial perfusion imaging (MPI) in symptomatic patients without in-stent restenosis. Materials and Methods: Thirty-seven (mean age, 71.3 ± 10 years; age range, 48-88 years; 31 males, 6 females) consecutive symptomatic patients with patent coronary stents and without obstructive de novo lesions were prospectively enrolled to undergo dynamic CT-MPI using a third-generation dual-source CT scanner. The shuttle-mode acquisition technique was used to image the complete left ventricle. A bolus of contrast media (50 mL; iopromide, 370 mg iodine/mL) was injected into the antecubital vein at a rate of 6 mL/s, followed by a 40-mL saline flush. The mean MBF value and other quantitative parameters were measured for each segment of both stented-vessel territories and reference territories. The MBFratio was defined as the ratio of the mean MBF value of the whole stent-vessel territory to that of the whole reference territory. An MBFratio of 0.85 was used as the cut-off value to distinguish hypoperfused from non-hypoperfused segments. Results: A total of 629 segments of 37 patients were ultimately included for analysis. The mean effective dose of dynamic CT-MPI was 3.1 ± 1.2 mSv (range, 1.7-6.3 mSv). The mean MBF of stent-vessel territories was decreased in 19 lesions and 81 segments. Compared to stent-vessel territories without hypoperfusion, the mean MBF and myocardial blood volume were markedly lower in hypoperfused stent-vessel territories (77.5 ± 16.6 mL/100 mL/min vs. 140.4 ± 24.1 mL/100 mL/min [p < 0.001] and 6.4 ± 3.7 mL/100 mL vs. 11.5 ± 4 mL/100 mL [p < 0.001, respectively]). Myocardial hypoperfusion in stentvessel territories was present in 48.6% (18/37) of patients. None of clinical parameters differed statistically significantly between hypoperfusion and non-hypoperfusion subgroups. Conclusion: Decreased MBF is commonly present in patients who are symptomatic after percutaneous coronary intervention, despite patent stents and can be detected by dynamic CT-MPI using a low radiation dose.