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991.
DNA data and morphology reveal the existence of Kentrochrysalis streckeri Staudinger, 1880 (Lepidoptera: Sphingidae) instead of K. consimilis in South Korea 下载免费PDF全文
Min Jee Kim Sung‐Soo Kim Sei‐Woong Choi Youngho Cho Iksoo Kim 《Entomological Research》2016,46(3):210-219
In the present study, we determined that specimens of Kentrochrysalis consimilis collected from South Korea were K. streckeri, rather than K. consimilis, based on morphology, DNA barcodes and nuclear elongation factor 1 alpha (EF‐1α) sequences. The major morphological differences between K. streckeri and K. consimilis include the shape of forewing and hind‐wing pattern elements and male and female genitalia. The DNA barcode analysis of the South Korean specimens and the Russia‐originated K. streckeri showed a maximum sequence divergence of only 0.659% (4 bp), whereas that of the South Korean specimens and Japan‐originated K. consimilis showed a minimum sequence divergence of 2.965% (18 bp), indicating that the Korean specimens are, in fact, K. streckeri and not K. consimilis. Phylogenetic analyses both by Bayesian inference and maximum likelihood methods strongly clustered the South Korean specimens and Russian K. streckeri into one group, excluding K. consimilis. The EF‐1α‐based sequence and phylogenetic analyses of the two species also supported data from the DNA barcode, indicating the distribution of K. streckeri in South Korea, instead of K. consimilis. 相似文献
992.
Intravascular magnetomotive optical coherence tomography of targeted early‐stage atherosclerotic changes in ex vivo hyperlipidemic rabbit aortas 下载免费PDF全文
Jongsik Kim Adeel Ahmad Joanne Li Marina Marjanovic Eric J. Chaney Kenneth S. Suslick Stephen A. Boppart 《Journal of biophotonics》2016,9(1-2):109-116
We report the development of an intravascular magnetomotive optical coherence tomography (IV‐MM‐OCT) system used with targeted protein microspheres to detect early‐stage atherosclerotic fatty streaks/plaques. Magnetic microspheres (MSs) were injected in vivo in rabbits, and after 30 minutes of in vivo circulation, excised ex vivo rabbit aorta samples specimens were then imaged ex vivo with our prototype IV‐MM‐OCT system. The alternating magnetic field gradient was provided by a unique pair of external custom‐built electromagnetic coils that modulated the targeted magnetic MSs. The results showed a statistically significant MM‐OCT signal from the aorta samples specimens injected with targeted MSs.
993.
Serial Change in Cervical Length for the Prediction of Emergency Cesarean Section in Placenta Previa
Purpose
To evaluate whether serial change in cervical length (CL) over time can be a predictor for emergency cesarean section (CS) in patients with placenta previa.Methods
This was a retrospective cohort study of patients with placenta previa between January 2010 and November 2014. All women were offered serial measurement of CL by transvaginal ultrasound at 19 to 23 weeks (CL1), 24 to 28 weeks (CL2), 29 to 31 weeks (CL3), and 32 to 34 weeks (CL4). We compared clinical characteristics, serial change in CL, and outcomes between the emergency CS group (case group) and elective CS group (control group). The predictive value of change in CL for emergency CS was evaluated.Results
A total of 93 women were evaluated; 31 had emergency CS due to massive vaginal bleeding. CL tended to decrease with advancing gestational age in each group. Until 29–31 weeks, CL showed no significant differences between the two groups, but after that, CL in the emergency CS group decreased abruptly, even though CL in the elective CS group continued to gradually decrease. On multivariate analysis to determine risk factors, only admissions for bleeding (odds ratio, 34.710; 95% CI, 5.239–229.973) and change in CL (odds ratio, 3.522; 95% CI, 1.210–10.253) were significantly associated with emergency CS. Analysis of the receiver operating characteristic curve showed that change in CL could be the predictor of emergency CS (area under the curve 0.734, p < 0.001), with optimal cutoff for predicting emergency cesarean delivery of 6.0 mm.Conclusions
Previous admission for vaginal bleeding and change in CL are independent predictors of emergency CS in placenta previa. Women with change in CL more than 6 mm between the second and third trimester are at high risk of emergency CS in placenta previa. Single measurements of short CL at the second or third trimester do not seem to predict emergency CS. 相似文献994.
995.
Hyun Jung Koo Myoungsun Lee Jin Kim Chul Woong Woo Seong-Yun Jeong Eun Kyung Choi Namkug Kim Jin Seong Lee 《PloS one》2016,11(2)
Purpose
We assessed the effects of anti-angiogenic therapy (AAT) on radiation therapy (RT), evaluating the tumor growth and perfusion patterns on dynamic contrast enhanced MR (DCE-MR) images.Methods
Thirteen nude mice with heterotopic xenograft cancer of human lung cancer cell line were used. To observe the interval change of the tumor size and demonstrate the time-signal intensity enhancement curve of the tumor, the mice were subdivided into four groups: control (n = 2), AAT (n = 2), RT (n = 5), and combined therapy (AART, n = 4). DCE-MR images were taken four weeks after treatment. Perfusion parameters were obtained based on the Brix model. To compare the interval size changes in the RT group with those in the AART group, repeated measures ANOVA was used. Perfusion parameters in both the RT and AART groups were compared using a Mann-Whitney U test.Results
Tumor growth was more suppressed in AART group than in the other groups. Control group showed the rapid wash-in and wash-out pattern on DCE-MR images. In contrast to RT group with delayed and prolonged enhancement, both AAT and AART groups showed the rapid wash-in and plateau pattern. The signal intensity in the plateau/time to peak enhancement (P<0.016) and the maximum enhancement ratio (P<0.016) of AART group were higher than those of RT group.Conclusions
AART showed synergistic effects in anticancer treatment. The pattern of the time-intensity curve on the DCE-MR images in each group implies that AAT might help maintain the perfusion in the cancer of AART group. 相似文献996.
Hye Ran Park Jae Meen Lee Gwanhee Ehm Hui-Jun Yang In Ho Song Yong Hoon Lim Mi-Ryoung Kim Keyoung Ran Kim Woong-Woo Lee Young Eun Kim Jae Ha Hwang Chae Won Shin Hyeyoung Park Jin Wook Kim Han-Joon Kim Cheolyoung Kim Dong Gyu Kim Beom Seok Jeon Sun Ha Paek 《PloS one》2016,11(1)
Background
GPi (Internal globus pallidus) DBS (deep brain stimulation) is recognized as a safe, reliable, reversible and adjustable treatment in patients with medically refractory dystonia.Objectives
This report describes the long-term clinical outcome of 36 patients implanted with GPi DBS at the Neurosurgery Department of Seoul National University Hospital.Methods
Nine patients with a known genetic cause, 12 patients with acquired dystonia, and 15 patients with isolated dystonia without a known genetic cause were included. When categorized by phenomenology, 29 patients had generalized, 5 patients had segmental, and 2 patients had multifocal dystonia. Patients were assessed preoperatively and at defined follow-up examinations postoperatively, using the Burke-Fahn-Marsden dystonia rating scale (BFMDRS) for movement and functional disability assessment. The mean follow-up duration was 47 months (range, 12–84)Results
The mean movement scores significantly decreased from 44.88 points preoperatively to 26.45 points at 60-month follow up (N = 19, P = 0.006). The mean disability score was also decreased over time, from 11.54 points preoperatively to 8.26 points at 60-month follow up, despite no statistical significance (N = 19, P = 0.073). When analyzed the movement and disability improvement rates at 12-month follow up point, no significant difference was noted according to etiology, disease duration, age at surgery, age of onset, and phenomenology. However, the patients with DYT-1 dystonia and isolated dystonia without a known genetic cause showed marked improvement.Conclusions
GPi DBS is a safe and efficient therapeutic method for treatment of dystonia patients to improve both movement and disability. However, this study has some limitations caused by the retrospective design with small sample size in a single-center. 相似文献997.
Ingrid C. Rulifson Ping Cao Li Miao David Kopecky Linda Huang Ryan D. White Kim Samayoa Jonitha Gardner Xiaosu Wu Kui Chen Trace Tsuruda Oliver Homann Helene Baribault Harvey Yamane Tim Carlson Jed Wiltzius Yang Li 《PloS one》2016,11(2)
Pancreatic amyloid formation by islet amyloid polypeptide (IAPP) is a hallmark pathological feature of type 2 diabetes. IAPP is stored in the secretory granules of pancreatic beta-cells and co-secreted with insulin to maintain glucose homeostasis. IAPP is innocuous under homeostatic conditions but imbalances in production or processing of IAPP may result in homodimer formation leading to the rapid production of cytotoxic oligomers and amyloid fibrils. The consequence is beta-cell dysfunction and the accumulation of proteinaceous plaques in and around pancreatic islets. Beta-site APP-cleaving enzyme 2, BACE2, is an aspartyl protease commonly associated with BACE1, a related homolog responsible for amyloid processing in the brain and strongly implicated in Alzheimer’s disease. Herein, we identify two distinct sites of the mature human IAPP sequence that are susceptible to BACE2-mediated proteolytic activity. The result of proteolysis is modulation of human IAPP fibrillation and human IAPP protein degradation. These results suggest a potential therapeutic role for BACE2 in type 2 diabetes-associated hyperamylinaemia. 相似文献
998.
Siddique A. Abbasi Ravi V. Shah Steven E. McNulty Adrian F. Hernandez Marc J. Semigran Gregory D. Lewis Michael Jerosch-Herold Raymond J. Kim Margaret M. Redfield Raymond Y. Kwong 《PloS one》2016,11(11)
Given the emerging recognition of left atrial structure and function as an important marker of disease in heart failure with preserved ejection fraction (HF-pEF), we investigated the association between left atrial volume and function with markers of disease severity and cardiac structure in HF-pEF. We studied 100 patients enrolled in the PhosphdiesteRasE-5 Inhibition to Improve CLinical Status and EXercise Capacity in Diastolic Heart Failure (RELAX) trial who underwent cardiac magnetic resonance (CMR), cardiopulmonary exercise testing, and blood collection before randomization. Maximal left atrial volume index (LAVi; N = 100), left atrial emptying fraction (LAEF; N = 99; including passive and active components (LAEFP, LAEFA; N = 80, 79, respectively) were quantified by CMR. After adjustment for multiple testing, maximal LAVi was only associated with age (ρ = 0.39), transmitral filling patterns (medial E/e’ ρ = 0.43), and N-terminal pro-BNP (NT-proBNP; ρ = 0.65; all p<0.05). Lower LAEF was associated with older age, higher transmitral E/A ratio and higher NT-proBNP. Peak VO2 and VE/VCO2 slope were not associated with left atrial structure or function. After adjustment for age, sex, transmitral E/A ratio, CMR LV mass, LV ejection fraction, and creatinine clearance, NT-proBNP remained associated with maximal LAVi (β = 0.028, p = 0.0007) and total LAEF (β = -0.033, p = 0.001). Passive and active LAEF were most strongly associated with age and NT-proBNP, but not gas exchange or other markers of ventricular structure or filling properties. Left atrial volume and emptying function are associated most strongly with NT-proBNP and diastolic filling properties, but not significantly with gas exchange, in HFpEF. Further research to explore the relevance of left atrial structure and function in HF-pEF is warranted. 相似文献
999.