831 research outputs found
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Altered expression of norepinephrine transporter and norepinephrine in human placenta cause pre-eclampsia through regulated trophoblast invasion
Objective: We investigated the norepinephrine transporter (NET) expression in normal and pre-eclamptic placentas and analyzed the invasion activity of trophoblastic cells based on norepinephrine (NE)-NET regulation. Methods: NET and NE expression levels were examined by western blot and enzyme-linked immunosorbent assay, respectively. Trophoblast invasion activity, depending on NE-NET regulation, was determined by NET-small interfering RNA (siRNA) and NET transfection into the human extravillous trophoblast cells with or without NE treatment and invasion rates were analyzed by zymography and an invasion assay. Results: NET mRNA was expressed at a low level in pre-eclamptic placentas compared with normal placentas and NE concentration in maternal plasma increased significantly in pre-eclamptic women compared to normal pregnant women (p<0.05). NET gene upregulation and NE treatment stimulated trophoblast cell invasion up to 2.5-fold (p<0.05) by stimulating matrix metalloproteinase-9 activity via the phosphoinositol-3-kinase/AKT signaling pathway, whereas NET-siRNA with NE treatment reduced invasion rates. Conclusion: NET expression is reduced by inadequate regulation of NE levels during placental development. This suggests that a complementary balance between NET and NE regulates trophoblast cell invasion activities during placental development
On Stein's Identity and Near-Optimal Estimation in High-dimensional Index Models
We consider estimating the parametric components of semi-parametric multiple
index models in a high-dimensional and non-Gaussian setting. Such models form a
rich class of non-linear models with applications to signal processing, machine
learning and statistics. Our estimators leverage the score function based first
and second-order Stein's identities and do not require the covariates to
satisfy Gaussian or elliptical symmetry assumptions common in the literature.
Moreover, to handle score functions and responses that are heavy-tailed, our
estimators are constructed via carefully thresholding their empirical
counterparts. We show that our estimator achieves near-optimal statistical rate
of convergence in several settings. We supplement our theoretical results via
simulation experiments that confirm the theory
Automatic 3D Model Generation based on a Matching of Adaptive Control Points
Abstract The use of a 3D model helps to diagnosis and accurately locate a disease where it is neither available, nor can be exactly measured in a 2D image. Therefore, highly accurate software for a 3D model of vessel is required for an accurate diagnosis of patients. We have generated standard vessel because the shape of the arterial is different for each individual vessel, where the standard vessel can be adjusted to suit individual vessel. In this paper, we propose a new approach for an automatic 3D model generation based on a matching of adaptive control points. The proposed method is carried out in three steps. First, standard and individual vessels are acquired. The standard vessel is acquired by a 3D model projection, while the individual vessel of the first segmented vessel bifurcation is obtained. Second is matching the corresponding control points between the standard and individual vessels, where a set of control and corner points are automatically extracted using the Harris corner detector. If control points exist between corner points in an individual vessel, it is adaptively interpolated in the corresponding standard vessel which is proportional to the distance ratio. And then, the control points of corresponding individual vessel match with those control points of standard vessel. Finally, we apply warping on the standard vessel to suit the individual vessel using the TPS (Thin Plate Spline) interpolation function. For experiments, we used angiograms of various patients from a coronary angiography in Sanggye Paik Hospital
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Estimating the malaria transmission of Plasmodium vivax based on serodiagnosis
Background: Plasmodium vivax re-emerged in 1993 and has now become a major public health problem during the summer season in South Korea. The aim of this study was to interpret and understand the meaning of seroepidemiological studies for developing the best malaria control programme in South Korea. Methods: Blood samples were collected in Gimpo city, Paju city, Yeoncheon County, Cheorwon County and Goseong County of high risk area in South Korea. Microscopy was performed to identify patients infected with P. vivax. Antibody detection for P. vivax was performed using indirect fluorescent antibody test (IFAT). Results: A total of 1,574 blood samples was collected from participants in the study areas and evaluated against three parameters: IFAT positive rate, annual antibody positive index (AAPI), and annual parasite index (API). The IFAT positive rate was 7.24% (n = 114). Of the five study areas, Gimpo had the highest IFAT positive rate (13.68%) and AAPI (4.63). Yeongcheon had the highest API in 2005 (2.06) while Gimpo had the highest API in 2006 (5.00). No correlation was observed between any of the three parameters and study sites' distance from the demilitarized zone (DMZ). Conclusions: These results showed that P. vivax antibody levels could provide useful information about the prevalence of malaria in endemic areas. Furthermore, AAPI results for each year showed a closer relationship to API the following year than the API of the same year and thus could be helpful in predicting malaria transmission risks
Variation of quercetin glycoside derivatives in three onion (Allium cepa L.) varieties
AbstractThe aim of this study was to quantify the contents of individual quercetin glycosides in red, yellow and chartreuse onion by High Performance Liquid Chromatography (HPLC) analysis. Acid hydrolysis of individual quercetin glycosides using 6M hydrochloric acid guided to identify and separate quercetin 7,4ā²-diglucoside, quercetin 3-glucoside, quercetin 4ā²-glucoside, and quercetin. The contents of total quercetin glycosides varied extensively among three varieties (ranged from 16.10 to 103.93mg/g DW). Quercetin was the predominant compound that accounted mean 32.21mg/g DW in red onion (43.6% of the total) and 127.92mg/g DW in chartreuse onion (78.3% of the total) followed by quercetin 3-glucoside (28.83 and 24.16mg/g DW) respectively. Quercetin 3-glucoside levels were much higher in yellow onion (43.85mg/g DW) followed by quercetin 30.08mg/g DW. Quercetin 4ā²-glucoside documented the lowest amount that documented mean 2.4% of the total glycosides. The varied contents of glycosides present in the different onion varieties were significant
Long-term evaluation of the prognosis of super hydrophilic surface treated CA implants: a retrospective clinical study
This study was performed to evaluate the long-term clinical efficacy of the CA implants (Osstem Implant, Busan, Korea), calcium-modified surfaced treated implants on acid-etched surfaces sandblasted with alumina.
From January 2013 to December 2015, 258 implants of 120 patients placed between 2013 and 2015 were retrospectively studied. Using medical records and periapical radiographs, sex, age, location, fixture width and length of placed implants, presence or absence of bone graft, types of bone substitutes and membrane used for bone grafting, primary and secondary stability, initial and delayed complications, and marginal bone loss were investigated. The success rate and survival rate of the implants in each group were analyzed retrospectively based on the criteria suggested by Albrektsson et al.
Between 2013 and 2015, with a follow-up longer than 5years, 258 implants with an average diameter of 4.63mm (3.5ā5.5mm) and an average length of 9.94mm (7.0ā13.0mm) were placed in a total of 120 patients (61 males and 59 females) with a mean age of 63.7years for an average of 62months of observation period. The survival rate was 97.3%, the success rate was 94.2%, and the average final marginal bone loss was 0.074mm.
The CA implants manufactured with the improved surface treatment method exhibited a survival rate of 97.3% and a success rate of 94.2% over an average observation period of 62months. The implants were not affected by most factors and had very high survival and success rates over a long period of observation. In particular, the stability of the implant was excellent, with no cases of failed implants in delayed placement after bone grafting and a healing period
TSLP Induces Mast Cell Development and Aggravates Allergic Reactions through the Activation of MDM2 and STAT6
Thymic stromal lymphopoietin (TSLP) is known to promote T helper type 2 cellāassociated inflammation. Mast cells are major effector cells in allergic inflammatory responses. We noted that the population and maturation of mast cells were reduced in TSLP-deficient mice (TSLP-/-). Thus, we hypothesized that TSLP might affect mast cell development. We found that TSLP induced the proliferation and differentiation of mast cells from bone marrow progenitors. TSLP-induced mast cell proliferation was abolished by depletion of mouse double minute 2 (MDM2) and signal transducers and activators of transcription 6 (STAT6), as an upstream activator of MDM2. TSLP-/-, in particular, had a considerable deficit in the expression of MDM2 and STAT6. Also, the TSLP deficiency attenuated mast cellāmediated allergic reactions through the downregulation of STAT6 and MDM2. In an antibody microarray chip analysis, MDM2 expression was increased in atopic dermatitis patients. These observations indicate that TSLP is a factor for mast cell development, and that it aggravates mast cellāmediated immune responses
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