199 research outputs found
Toward Optimal Churn Management: A Partial Least Square (PLS) Model
In a very competitive mobile telecommunication industry business environment, marketing managers need a business intelligence model that allows them to maintain an optimal (at least a near optimal) level of churners very effectively and efficiently while minimizing the costs throughout their marketing programs. As a first step toward optimal churn management program for marketing managers, this paper focuses on building an accurate and concise predictive model for the purpose of churn prediction utilizing a Partial Least Square (PLS)-based methodology on highly correlated data sets among variables. A preliminary experiment demonstrates that the presented model provides more accurate performance than traditional prediction models and identifies key variables to better understand churning behaviors
Acute kidney injury in pediatric patients with rhabdomyolysis
PurposeThis study aimed to evaluate the clinical findings in pediatric rhabdomyolysis and the predictive factors for acute kidney injury (AKI) in Korean children.MethodsMedical records of 39 Korean children, who were newly diagnosed with rhabdomyolysis from January 2008 to December 2015, were retrospectively analyzed. The diagnosis was made from the medical history, elevated serum creatinine kinase level >1,000 IU/L, and plasma myoglobin level >150 ng/mL. Patients with muscular dystrophy and myocardial infarction were excluded.ResultsThe median patient age at diagnosis was 14.0 years (range, 3–18 years), and the male to female ratio was 2.5. The most common presenting symptom was myalgia (n=25, 64.1%), and 14 patients (35.9%) had rhabdomyolysis-induced AKI. Eighteen patients (46.2%) had underlying diseases, such as epilepsy and psychotic disorders. Ten of these patients showed rhabdomyolysis-induced AKI. The common causes of rhabdomyolysis were infection (n=12, 30.7%), exercise (n=9, 23.1%), and trauma (n=8, 20.5%). There was no difference in the distribution of etiology between AKI and non-AKI groups. Five patients in the AKI group showed complete recovery of renal function after stopping renal replacement therapy. The median length of hospitalization was 7.0 days, and no mortality was reported. Compared with the non-AKI group, the AKI group showed higher levels of peak creatinine kinase and myoglobin, without statistical significance.ConclusionThe clinical characteristics of pediatric rhabdomyolysis differ from those observed in adult patients. Children with underlying diseases are more vulnerable to rhabdomyolysis-induced AKI. AKI more likely develops in the presence of a high degree of albuminuria
[2-(4-ChloroÂphenÂyl)-5-phenylÂoxolan-3-yl](cycloÂpentenÂyl)methanone
In the title compound, C22H21ClO2, the oxolane ring adopts a twisted conformation. The dihedral angles between the mean plane of the oxolane ring and the mean planes of the 4-chloroÂphenyl, phenyl and cycloÂpentenyl rings are 71.81 (18), 76.9 (18) and 82.08 (18)°, respectively
The anti-angiogenic herbal composition Ob-X inhibits adipose tissue growth in obese mice
Objective: The growth and development of adipose tissue are thought to be associated with angiogenesis and extracellular matrix remodeling. Since the composition of the herbal extract called Ob-X has been shown to have both anti-angiogenic and matrix metalloproteinase (MMP)-inhibiting activities, we hypothesized that growth of adipose tissue can be regulated by Ob-X. Materials and Methods: The effects of Ob-X on angiogenesis and extracellular matrix remodeling were measured using in vitro and ex vivo assays. The effects of Ob-X on adipose tissue growth were investigated with nutritionally obese mice. Results: Ob-X inhibited angiogenesis in a dose-dependent manner in the human umbilical vein endothelial cell (HUVEC) tube formation assay in vitro and the rat aortic ring assay ex vivo. Ob-X also suppressed MMP activity in vitro. Administration of Ob-X to high fat diet-induced obese mice produced significant reductions in body weight gain and adipose tissue mass, compared to controls. The mass of both subcutaneous (SC) and visceral (VSC) fat was reduced in Ob-X-treated mice. The size of adipocytes in SC and VSC adipose tissues was also significantly reduced in Ob-X-treated mice. Ob-X treatment decreased the blood vessel density and MMP activity in VSC adipose tissues of nutritionally obese mice. Ob-X reduced mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas it increased mRNA levels of angiogenesis inhibitors (TSP-1 and TIMP-2) in SC and VSC adipose tissues of nutritionally obese mice. Conclusion: Ob-X, which has anti-angiogenic and MMP-inhibitory activities, reduces adipose tissue mass in nutritionally induced obese mice, providing evidence that adipose tissue growth and development may be prevented by inhibiting angiogenesis. In addition, these data suggest that regulation of adipose tissue growth by inhibiting angiogenesis may alter the expression of genes involved in angiogenesis and the MMP system
Distinct regulatory pathways contribute to dynamic CHH methylation patterns in transposable elements throughout Arabidopsis embryogenesis
CHH methylation (mCHH) increases gradually during embryogenesis across dicotyledonous plants, indicating conserved mechanisms of targeting and conferral. Although it is suggested that methylation increase during embryogenesis enhances transposable element silencing, the detailed epigenetic pathways underlying this process remain unclear. In Arabidopsis, mCHH is regulated by both small RNA-dependent DNA methylation (RdDM) and RNA-independent Chromomethylase 2 (CMT2) pathways. Here, we conducted DNA methylome profiling at five stages of Arabidopsis embryogenesis, and classified mCHH regions into groups based on their dependency on different methylation pathways. Our analysis revealed that the gradual increase in mCHH in embryos coincided with the expansion of small RNA expression and regional mCHH spreading to nearby sites at numerous loci. We identified distinct methylation dynamics in different groups of mCHH targets, which vary according to transposon length, location, and cytosine frequency. Finally, we highlight the characteristics of transposable element loci that are targeted by different mCHH machinery, showing that short, heterochromatic TEs with lower mCHG levels are enriched in loci that switch from CMT2 regulation in leaves, to RdDM regulation during embryogenesis. Our findings highlight the interplay between the length, location, and cytosine frequency of transposons and the mCHH machinery in modulating mCHH dynamics during embryogenesis
Recommended from our members
Supercooling as a Viable Non-Freezing Cell Preservation Method of Rat Hepatocytes
Supercooling preservation holds the potential to drastically extend the preservation time of organs, tissues and engineered tissue products, and fragile cell types that do not lend themselves well to cryopreservation or vitrification. Here, we investigate the effects of supercooling preservation (SCP at -4oC) on primary rat hepatocytes stored in cryovials and compare its success (high viability and good functional characteristics) to that of static cold storage (CS at +4oC) and cryopreservation. We consider two prominent preservation solutions a) Hypothermosol (HTS-FRS) and b) University of Wisconsin solution (UW) and a range of preservation temperatures (-4 to -10 oC). We find that there exists an optimum temperature (-4oC) for SCP of rat hepatocytes which yields the highest viability; at this temperature HTS-FRS significantly outperforms UW solution in terms of viability and functional characteristics (secretions and enzymatic activity in suspension and plate culture). With the HTS-FRS solution we show that the cells can be stored for up to a week with high viability (~56%); moreover we also show that the preservation can be performed in large batches (50 million cells) with equal or better viability and no loss of functionality as compared to smaller batches (1.5 million cells) performed in cryovials
Neuropeptides SP and CGRP Underlie the Electrical Properties of Acupoints
Electrical skin measurements at acupuncture points (acupoints) have been utilized as a diagnostic and therapeutic aid for more than 50 years. Although acupoints are described as having distinct electrical properties, such as high conductance and low impedance, the underlying mechanisms are currently unknown. The present study investigated in a rat model of hypertension whether the high conductance at acupoints is a result of the release of the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) during neurogenic inflammation in the referred pain area. When plasma extravasation from neurogenic inflammation was examined by exploring the leakage of intravenously injected Evans blue dye (EBD) to the skin, extravasated EBD was found most frequently in acupoints on the wrist. The increased conductance and temperature at these acupoints occurred during the development of hypertension. The increase in conductance and plasma extravasation at acupoints in hypertensive rats was ablated by cutting median and ulnar nerves, blocking small diameter afferent fibers with resiniferatoxin (RTX) injection into median and ulnar nerves, or antagonizing SP or CGRP receptors in acupoints. In turn, intradermal injection of SP or CGRP resulted in increased conductance and plasma extravasation in naïve rats. Elevated levels of SP and CGRP were found in the acupoints of hypertensive rats. These findings suggest that the high conductance at acupoints is due to vascular leakage following local release of SP and CGRP during neurogenic inflammation
Evaluating Acupuncture Point and Nonacupuncture Point Stimulation with EEG: A High-Frequency Power Spectrum Analysis
To identify physical and sensory responses to acupuncture point stimulation (APS), nonacupuncture point stimulation (NAPS) and no stimulation (NS), changes in the high-frequency power spectrum before and after stimulation were evaluated with electroencephalography (EEG). A total of 37 healthy subjects received APS at the LI4 point, NAPS, or NS with their eyes closed. Background brain waves were measured before, during, and after stimulation using 8 channels. Changes in the power spectra of gamma waves and high beta waves before, during, and after stimulation were comparatively analyzed. After NAPS, absolute high beta power (AHBP), relative high beta power (RHBP), absolute gamma power (AGP), and relative gamma power (RGP) tended to increase in all channels. But no consistent notable changes were found for APS and NS. NAPS is believed to cause temporary reactions to stress, tension, and sensory responses of the human body, while APS responds stably compared to stimulation of other parts of the body
- …