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101.
Seok-Chan Hong Jeffrey D. Suh Sochung Chung Seung-Hoon Lee Ji Ho Choi Jeong In Oh In-Tae Kim Jin Kook Kim Jae Hoon Cho 《Clinical and experimental otorhinolaryngology》2015,8(4):381-384
Objectives
To evaluate the association between catecholamine levels and skin prick test results among children.Methods
Two hundred eight first grade children from one elementary school were invited to participate in this study. Skin prick test (SPT) for six allergens (2 house dust mites, cat, dog, mugwort, and pollen mixture) was performed, and patient demographic information was recorded. The parents were surveyed using questionnaires about rhinitis-related symptoms. Finally, venous blood sampling was done to measure catecholamine levels (epinephrine, norepinephrine, and dopamine) by high-performance liquid chromatography.Results
Out of 208 children, 174 (106 boys and 68 girls) enrolled in this study. Ninety-six of the children (55%) had negative SPT (nonsensitization group), while 78 (45%) had a positive SPT to at least one of six allergens (sensitization group). The diagnosis of chronic rhinitis was more prevalent in the sensitization group (35.9%) than nonsensitization group (26.0%), however the finding was not significant (P=0.186). Epinephrine levels were decreased between the sensitization group compared to the nonsensitization group (P=0.004). There was no difference in norepinephrine and dopamine levels (P>0.05).Conclusion
Epinephrine levels are lower in children with positive SPT compared to controls, however, the level of the catecholamine was not associated with the presence or absence of rhinitis symptoms. 相似文献102.
Reto Burri Alexander Nater Takeshi Kawakami Carina F. Mugal Pall I. Olason Linnea Smeds Alexander Suh Ludovic Dutoit Stanislav Bure? Laszlo Z. Garamszegi Silje Hogner Juan Moreno Anna Qvarnstr?m Milan Ru?i? Stein-Are S?ther Glenn-Peter S?tre Janos T?r?k Hans Ellegren 《Genome research》2015,25(11):1656-1665
Speciation is a continuous process during which genetic changes gradually accumulate in the genomes of diverging species. Recent studies have documented highly heterogeneous differentiation landscapes, with distinct regions of elevated differentiation (“differentiation islands”) widespread across genomes. However, it remains unclear which processes drive the evolution of differentiation islands; how the differentiation landscape evolves as speciation advances; and ultimately, how differentiation islands are related to speciation. Here, we addressed these questions based on population genetic analyses of 200 resequenced genomes from 10 populations of four Ficedula flycatcher sister species. We show that a heterogeneous differentiation landscape starts emerging among populations within species, and differentiation islands evolve recurrently in the very same genomic regions among independent lineages. Contrary to expectations from models that interpret differentiation islands as genomic regions involved in reproductive isolation that are shielded from gene flow, patterns of sequence divergence (dxy and relative node depth) do not support a major role of gene flow in the evolution of the differentiation landscape in these species. Instead, as predicted by models of linked selection, genome-wide variation in diversity and differentiation can be explained by variation in recombination rate and the density of targets for selection. We thus conclude that the heterogeneous landscape of differentiation in Ficedula flycatchers evolves mainly as the result of background selection and selective sweeps in genomic regions of low recombination. Our results emphasize the necessity of incorporating linked selection as a null model to identify genome regions involved in adaptation and speciation.Uncovering the genetic architecture of reproductive isolation and its evolutionary history are central tasks in evolutionary biology. The identification of genome regions that are highly differentiated between closely related species, and thereby constitute candidate regions involved in reproductive isolation, has recently been a major focus of speciation genetic research. Studies from a broad taxonomic range, involving organisms as diverse as plants (Renaut et al. 2013), insects (Turner et al. 2005; Lawniczak et al. 2010; Nadeau et al. 2012; Soria-Carrasco et al. 2014), fishes (Jones et al. 2012), mammals (Harr 2006), and birds (Ellegren et al. 2012) contribute to the emerging picture of a genomic landscape of differentiation that is usually highly heterogeneous, with regions of locally elevated differentiation (“differentiation islands”) widely spread over the genome. However, the evolutionary processes driving the evolution of the differentiation landscape and the role of differentiation islands in speciation are subject to controversy (Turner and Hahn 2010; Cruickshank and Hahn 2014; Pennisi 2014).Differentiation islands were originally interpreted as “speciation islands,” regions that harbor genetic variants involved in reproductive isolation and are shielded from gene flow by selection (Turner et al. 2005; Soria-Carrasco et al. 2014). During speciation-with-gene-flow, speciation islands were suggested to evolve through selective sweeps of locally adapted variants and by hitchhiking of physically linked neutral variation (“divergence hitchhiking”) (Via and West 2008); gene flow would keep differentiation in the remainder of the genome at bay (Nosil 2008; Nosil et al. 2008). In a similar way, speciation islands can arise by allopatric speciation followed by secondary contact. In this case, genome-wide differentiation increases during periods of geographic isolation, but upon secondary contact, it is reduced by gene flow in genome regions not involved in reproductive isolation. In the absence of gene flow in allopatry, speciation islands need not (but can) evolve by local adaptation, but may consist of intrinsic incompatibilities sensu Bateson-Dobzhansky-Muller (Bateson 1909; Dobzhansky 1937; Muller 1940) that accumulated in spatially isolated populations.However, whether differentiation islands represent speciation islands has been questioned. Rather than being a cause of speciation, differentiation islands might evolve only after the onset of reproductive isolation as a consequence of locally accelerated lineage sorting (Noor and Bennett 2009; Turner and Hahn 2010; White et al. 2010; Cruickshank and Hahn 2014; Renaut et al. 2014), such as in regions of low recombination (Nachman 2002; Sella et al. 2009; Cutter and Payseur 2013). In these regions, the diversity-reducing effects of both positive selection and purifying selection (background selection [BGS]) at linked sites (“linked selection”) impact physically larger regions due to the stronger linkage among sites. The thereby locally reduced effective population size (Ne) will enhance genetic drift and hence inevitably lead to increased differentiation among populations and species.These alternative models for the evolution of a heterogeneous genomic landscape of differentiation are not mutually exclusive, and their population genetic footprints can be difficult to discern. In the cases of (primary) speciation-with-gene-flow and gene flow at secondary contact, shared variation outside differentiation islands partly stems from gene flow. In contrast, under linked selection, ancestral variation is reduced and differentiation elevated in regions of low recombination, while the remainder of the genome may still share considerable amounts of ancestral genetic variation and show limited differentiation. Many commonly used population genetic statistics do not capture these different origins of shared genetic variation and have the same qualitative expectations under both models, such as reduced diversity (π) and skews toward an excess of rare variants (e.g., lower Tajima''s D) in differentiation islands relative to the remainder of the genome. However, since speciation islands should evolve by the prevention or breakdown of differentiation by gene flow in regions not involved in reproductive isolation, substantial gene flow should be detectable in these regions (Cruickshank and Hahn 2014) and manifested in the form of reduced sequence divergence (dxy) or as an excess of shared derived alleles in cases of asymmetrical gene flow (Patterson et al. 2012). Under linked selection, predictions are opposite for dxy (Cruickshank and Hahn 2014), owing to reduced ancestral diversity in low-recombination regions. Further predictions for linked selection include positive and negative relationships of recombination rate with genetic diversity (π) and differentiation (FST), respectively, and inverse correlations of the latter two with the density of targets for selection. Finally, important insights into the nature of differentiation islands may be gained by studying the evolution of differentiation landscapes across the speciation continuum. Theoretical models and simulations of speciation-with-gene-flow predict that after an initial phase during which differentiation establishes in regions involved in adaptation, differentiation should start spreading from these regions across the entire genome (Feder et al. 2012, 2014; Flaxman et al. 2013).Unravelling the processes driving the evolution of the genomic landscape of differentiation, and hence understanding how genome differentiation unfolds as speciation advances, requires genome-wide data at multiple stages of the speciation continuum and in a range of geographical settings from allopatry to sympatry (Seehausen et al. 2014). Although studies of the speciation continuum are emerging (Hendry et al. 2009; Kronforst et al. 2013; Shaw and Mullen 2014, and references therein), empirical examples of genome differentiation at multiple levels of species divergence remain scarce (Andrew and Rieseberg 2013; Kronforst et al. 2013; Martin et al. 2013), and to our knowledge, have so far not jointly addressed the predictions of alternative models for the evolution of the genomic landscape of differentiation. In the present study, we implemented such a study design encompassing multiple populations of four black-and-white flycatcher sister species of the genus Ficedula (Fig. 1A,B; Supplemental Fig. S1; for a comprehensive reconstruction of the species tree, see Nater et al. 2015). Previous analyses in collared flycatcher (F. albicollis) and pied flycatcher (F. hypoleuca) revealed a highly heterogeneous differentiation landscape across the genome (Ellegren et al. 2012). An involvement of gene flow in its evolution would be plausible, as hybrids between these species occur at low frequencies in sympatric populations in eastern Central Europe and on the Baltic Islands of Gotland and Öland (Alatalo et al. 1990; Sætre et al. 1999), although a recent study based on genome-wide markers identified no hybrids beyond the F1 generation (Kawakami et al. 2014a). Still, gene flow from pied into collared flycatcher appears to have occurred (Borge et al. 2005; Backström et al. 2013; Nadachowska-Brzyska et al. 2013) despite premating isolation (for review, see Sætre and Sæther 2010), hybrid female sterility (Alatalo et al. 1990; Tegelström and Gelter 1990), and strongly reduced long-term fitness of hybrid males (Wiley et al. 2009). Atlas flycatcher (F. speculigera) and semicollared flycatcher (F. semitorquata) are two closely related species, which have been less studied, but may provide interesting insights into how genome differentiation evolves over time. Here, we take advantage of this system to identify the processes underlying the evolution of differentiation islands based on the population genetic analysis of whole-genome resequencing data of 200 flycatchers.Open in a separate windowFigure 1.A recurrently evolving genomic landscape of differentiation across the speciation continuum in Ficedula flycatchers. (A) Species’ neighbor-joining tree based on mean genome-wide net sequence divergence (dA). The same species tree topology was inferred with 100% bootstrap support from the distribution of gene trees under the multispecies coalescent (Supplemental Fig. S1). (B) Map showing the locations of population sampling and approximate species ranges. (C) Population genomic parameters along an example chromosome (Chromosome 4A) (see Supplemental Figs. S2, S4 for all chromosomes). Color codes for specific–specific parameters: (blue) collared; (green) pied; (orange) Atlas; (red) semicollared. Color codes for dxy: (green) collared-pied; (light blue) collared-Atlas; (blue) collared-semicollared; (orange) pied-Atlas; (red) pied-semicollared; (black) Atlas-semicollared. For differentiation within species, comparisons with the Italian (collared) and Spanish (pied) populations are shown. Color codes for FST within collared flycatchers: (cyan) Italy–Hungary; (light blue) Italy–Czech Republic; (dark blue) Italy–Baltic. Color codes for FST within pied flycatchers: (light green) Spain–Sweden; (green) Spain–Czech Republic; (dark green) Spain–Baltic. (D) Distributions of differentiation (FST) from collared flycatcher along the speciation continuum. Distributions are given separately for three autosomal recombination percentiles (33%; 33%–66%; 66%–100%) corresponding to high (>3.4 cM/Mb, blue), intermediate (1.3–3.4 cM/Mb, orange), and low recombination rate (0–1.3 cM/Mb, red), and the Z Chromosome (green). Geographically close within-species comparison: Italy–Hungary. Comparisons within species include the geographically close Italian and Hungarian populations (within [close]), and the geographically distant Italian and Baltic populations (within [far]). Geographically far within-species comparison: Italy–Baltic. (E) Differentiation from collared flycatcher along an example chromosome (Chromosome 11) (see Supplemental Fig. S3 for all chromosomes). Color codes for between-species comparisons: (green) pied; (orange) Atlas; (red) semicollared; (dark red) red-breasted; (black) snowy-browed flycatcher. Color codes for within-species comparisons: (cyan) Italy–Hungary; (blue) Italy–Baltic. Flycatcher artwork in panel A courtesy of Dan Zetterström. 相似文献
103.
Jin Young Kim Young Joo Suh Suyon Chang Dong Jin Im Yoo Jin Hong Hye-Jeong Lee Jin Hur Young Jin Kim Byoung Wook Choi 《The international journal of cardiovascular imaging》2018,34(2):293-300
The aim of our study was to investigate the feasibility of single-beat prospective electrocardiogram (ECG)-gated cardiac computed tomography (CT) using a 256-detector row wide-volume CT scanner for functional and anatomical evaluation of the aortic valve (AV) and coronary arteries in patients with AV disease. A total of 50 patients who underwent cardiac CT scan with a wide-volume 256-detector row CT scanner for the evaluation of AV and aorta were retrospectively enrolled. Cardiac CT was performed using the prospective ECG-gated acquisition mode, and AV image quality was analyzed using a four-point grading system. Severity of aortic stenosis (AS) and aortic regurgitation (AR) were assessed by CT and correlated to that assessed by transthoracic echocardiography (TTE) based on kappa statistics (κ). Estimated radiation exposure was assessed. Among 50 patients, 44 underwent cardiac CT with single-beat acquisition. The median image quality score of AV was 3.0 on the systolic phase and 4.0 on the diastolic phase. Severity of AS and AR by CT showed moderate agreement with TTE. The mean effective radiation dose was 3.75?±?1.43 mSv for CT angiography. Using 256-detector row wide-volume CT, the single-beat cardiac CT is feasible for evaluation of AV disease and the coronary arteries, with acceptable image quality and a low radiation dose of 3.75 mSv. 相似文献
104.
Siin Kim Hyungtae Kim Eunju Kim Sola Han Pratik P. Rane Kathleen M. Fox Zhongyun Zhao Yi Qian Hae Sun Suh 《Clinical therapeutics》2018,40(6):940-951.e7
105.
Vascular Pattern Analysis on Microvascular Sonography for Differentiation of Pleomorphic Adenomas and Warthin Tumors of Salivary Glands
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106.
Objectives:
Decreased fertility and impaired health owing to early menopause are significant health issues. Smoking is a modifiable health-related behavior that influences menopausal age. We investigated the effects of smoking-associated characteristics on menopausal age in Korean women.Methods:
This study used data from the Korea National Health and Nutrition Examination Survey from 2007 to 2012. Menopausal age in relation to smoking was analyzed as a Kaplan-Meier survival curve for 11 510 women (aged 30 to 65 years). The risk of entering menopause and experiencing early menopause (before age 48) related to smoking were assessed using a Cox proportional hazards model.Results:
The menopausal age among smokers was 0.75 years lower than that among non-smokers (p<0.001). The results of the Cox proportional hazards model showed pre-correction and post-correction risk ratios for entering menopause related to smoking of 1.26 (95% confidence interval [CI], 1.09 to 1.46) and 1.27 (95% CI, 1.10 to 1.47), respectively, and pre-correction and post-correction risk ratios for experiencing early menopause related to smoking of 1.36 (95% CI, 1.03 to 1.80) and 1.40 (95% CI, 1.05 to 1.85), respectively.Conclusions:
Smokers reached menopause earlier than non-smokers, and their risk for experiencing early menopause was higher. 相似文献107.
C M Ambrus J L Ambrus H Gastpar S D Sharma O W Suh R H Moore P Williams 《Angiology》1984,35(7):436-442
In vivo thrombolytic studies in stumptailed monkeys indicated that pentoxifylline potentiates thrombolysis induced by urokinase activated human plasmin. Pentoxifylline as well as prostaglandin E1 released plasminogen activators and activated the fibrinolysin system. From this point of view pentoxifylline and prostaglandin E1 synergized with each other. Pentoxifylline potentiated the thrombolytic effect of prostaglandin E1 in vivo. 相似文献
108.
Byun D Mohan S Kim C Suh K Yoo M Lee H Baylink DJ Qin X 《The Journal of clinical endocrinology and metabolism》2000,85(1):373-381
Insulin-like growth factor (IGF)-binding protein-4 (IGFBP-4), a consistent inhibitor of IGF action, is subject to proteolytic cleavage by the IGF-II-dependent IGFBP-4 protease. However, regulation of the IGF-II-dependent IGFBP-4 protease in vivo is not known. As IGFBP proteases are known to be triggered during pregnancy, we systematically evaluated the changes in IGFBP-4 proteolysis by serum collected throughout human pregnancy. Results from in vitro protease assays using recombinant IGFBP-4 revealed that IGFBP-4 proteolysis determined in both the presence and absence of exogenous IGF-II significantly increased during the first and second trimesters and reached a plateau by the third trimester. However, in the absence of IGF-II, IGFBP-4 proteolysis by pregnancy serum was only observed after prolonged incubation. IGF-II dose dependently increased IGFBP-4 proteolysis by pregnancy serum, with maximal stimulation observed at a concentration of 0.7 mol/L relative to IGFBP-4. In contrast, IGF-II at an equimolar dose had little effect on proteolysis of recombinant human IGFBP-3, whereas excess IGF-II reproducibly inhibited recombinant human IGFBP-3 proteolysis by pregnancy serum. Although IGF-II enhanced IGFBP-4 proteolysis, results from N-terminal sequence and mass spectrometric analyses of IGFBP-4 proteolytic fragments demonstrate that the cleavage site (Met135-Lys136) in human IGFBP-4 was not altered by IGF-II. Deletion of the residues 121-141 containing this cleavage site blocked IGFBP-4 proteolysis. These findings demonstrate that the increase in IGFBP-4 proteolysis during pregnancy was accounted for mainly by the IGF-II-dependent IGFBP-4 proteolysis. Because IGFBP-4 is a potent inhibitor of IGF actions, it can be speculated that the pregnancy-induced IGFBP-4 proteases may play an important role in regulating fetal growth. 相似文献
109.
Low grade gastric mucosa associated lymphoid tissue lymphoma:Treatment strategies based on 10 year follow-up 总被引:2,自引:0,他引:2
Lee SK Lee YC Chung JB Chon CY Moon YM Kang JK Park IS Suh CO Yang WI 《World journal of gastroenterology : WJG》2004,10(2):223-226
AIM: To deduce strategic guidelines of gastric mucosa associated lymphoid tissue lymphoma (MALTOMA) by evaluating the long-term outcome of patients in respect to various treatment modalities. METHODS: A total of 55 patients with MALTOMA from May 1992 to August 2002 were retrospectively reviewed. RESULTS: Complete remission was obtained in 24 (82.8%) of 29 patients treated with anti Helicobacter pylori (H pylori) regimen only. The duration to reach complete remission was 12 months (85 percentile, 2-33 months). Five patients showed complete remission with radiation therapy (26-86 months). Two of them were H pylori treatment failure cases. CONCLUSION: H pylori eradication is an effective primary treatment option for low grade MALTOMA and radiation therapy could be considered in patients with no evidence of H pylori infection or who do not respond to H pylori eradication therapy 12 months after successful eradication. 相似文献
110.
Oh HS Choi JH Park CK Jung CW Lee SI Park Q Suh C Kim SB Chi HS Lee JH Cho EK Bang SM Ahn MJ 《International journal of hematology》2002,76(5):465-470
Bone marrow angiogenesis has been reported to increase in several hematologic malignant diseases, including multiple myeloma. Because high-dose chemotherapy combined with autologous stem cell transplantation (SCT) improves the response rate, event-free survival, and overall survival in patients with multiple myeloma (MM), we studied the changes in bone marrow microvessel density (MVD) in 21 patients who underwent high-dose chemotherapy combined with autologous SCT to determine whether there was persistently increased angiogenesis at the time of response. Bone marrow biopsy specimens were obtained before and after SCT for each patient and immunostained with anti-CD34 antibodies for the identification of microvascular endothelial cells. The mean value of MVD in 21 MM patients at initial diagnosis was 46.0 +/- 24.0 and in healthy controls was 26.8 +/- 8.54 (P = .046). The mean MVD at initial diagnosis was 46.0 +/- 24.0 compared with 29.0 +/- 12.5 after achievement of response with SCT, and there was a statistically significant difference (P = .004). Sixteen of 21 patients (76.2%) had decreased MVD after SCT, and 5 patients were found to have a greater than 50% decrease in MVD after SCT. However, there was no difference in overall survival between the patient group with decreased MVD after SCT and that without decreased MVD (P = .9370). These results suggest that angiogenesis plays an important role in MM. In addition, the persistence of MVD at the time of response indicates continuous stimulus of microvessels by minimal residual disease even after SCT. 相似文献