정신증 초고위험군과 초발정신병에서 뇌 백질 네트워크의 차등적 변화

학위논문 (박사)-- 서울대학교 대학원 : 뇌인지과학과, 2015. 8. 권준수.A comprehensive figure of dysconnectivity in schizophrenia could be explored at the network level that not only accounts for local but also global organizational characteristics. However, no study has concurrently explored alteration in the white matter (WM) network of the brain of first-episode psychosis (FEP) and its prodromal stage to see whether differential changes in the structural network would exist according to the different stages of psychosis. Thirty-seven subjects with ultra-high risk for psychosis (UHR), 21 patients with FEP, and 37 healthy controls (HC) were recruited in the study. 3-Tesla T1 structural and diffusion tensor images were reconstructed as weighted WM networks of the brain by measuring number of axonal streamlines between 82 cortical and subcortical regions. Then, graph measures extracted from the networks were compared. Although global graph measures reflecting efficiency or small-world property of a network were not different between groups, the UHR group showed a higher assortativity coefficient compared to the FEP group and a higher modularity Q, without alteration in global clustering coefficient, compared to the HC group. At the local level, the FEP group showed a weaker WM connection between the left hippocampus and ipsilateral parahippocampal gyrus and a stronger WM connection between the left thalamus and ipsilateral superior frontal gyrus compared to the UHR and HC groups. More rightward asymmetry of the connections between both hippocampi and ipsilateral parahippocampal gyri was seen in the FEP compared to the UHR and HC groups, and rightward asymmetry of the connections correlated positively with psychotic symptoms and negatively with level of functioning in the UHR group. The participation coefficient of the right pallidum increased in the FEP compared to the UHR and HC groups, and the measure positively correlated with nonspecific psychiatric symptoms in the FEP group. UHR has enhanced resilience and adaptability of the WM network that may reflect highly variable prognosis of the stage among psychosis-continuum and defensive mechanism of the network against further damage. On the other hand, FEP has alteration mainly in the cortico-subcortical connectivity. These differential changes may reflect underlying biological mechanisms of developmental process leading to psychosis.Abstract ------------------------------------------------------------------------------ i Contents ---------------------------------------------------------------------------- iii List of Tables ---------------------------------------------------------------------- iv List of Figures ---------------------------------------------------------------------- v List of Abbreviations ------------------------------------------------------------- vi I. Introduction -------------------------------------------------------------------- 1 II. Methods ------------------------------------------------------------------------ 8 III. Results ------------------------------------------------------------------------ 24 IV. Discussion -------------------------------------------------------------------- 35 V. Conclusion -------------------------------------------------------------------- 45 VI. Reference -------------------------------------------------------------------- 46 VII. Appendix ------------------------------------------------------------------- 63 국문초록 ------------------------------------------------------------------------ 78Docto

High-resolution crystal structure of the non-specific lipid-transfer protein from maize seedlings

AbstractBackground: The movement of lipids between membranes is aided by lipid-transfer proteins (LTPs). Some LTPs exhibit broad specificity, transferring many classes of lipids, and are termed non-specific LTPs (ns-LTPs). Despite their apparently similar mode of action, no sequence homology exists between mammalian and plant ns-LTPs and no three-dimensional structure has been reported for any plant ns-LTP.Results We have determined the crystal structure of ns-LTP from maize seedlings by multiple isomorphous replacement and refined the structure to 1.9 å resolution. The protein comprises a single compact domain with four α-helices and a long C-terminal region. The eight conserved cysteines form four disulfide bridges (assigned as Cys4–Cys52, Cys14–Cys29, Cys30–Cys75, and Cys50–Cys89) resolving the ambiguity that remained from the chemical determination of pairings in the homologous protein from castor bean. Two of the bonds, Cys4–Cys52 and Cys50–Cys89, differ from what would have been predicted from sequence alignment with soybean hydrophobic protein. The complex between maize ns-LTP and hexadecanoate (palmitate) has also been crystallized and its structure refined to 1.8 å resolution.Conclusion The fold of maize ns-LTP places it in a new category of all-α-type structure, first described for soybean hydrophobic protein. In the absence of a bound ligand, the protein has a tunnel-like hydrophobic cavity, which is large enough to accommodate a long fatty acyl chain. In the structure of the complex with palmitate, most of the acyl chain is buried inside this hydrophobic cavity

Tunable colors of chiral liquid crystal displays

Abstract We report a method of the color variation in the reflective CLC displays depending on thermodynamically and the electric field switching. The reflective wavelength can be thermodynamically switched to reflect green from a cell initially reflecting a red color. Afterwards, the reflective wavelength can be electrically switched to reflect blue color. It is found that continuous decrease of the pitch is mainly originated from the dopant solubility below the critical temperature and stepwise decrease of the pitch is dominantly affected by the thermodynamic property above the critical temperature. The blue color change is a result of the compression to the helical pitches in planar layers in response to the applied voltage

Transcription Factor Sp1 Is Involved in Expressional Regulation of Coxsackie and Adenovirus Receptor in Cancer Cells

Coxsackie and adenovirus receptor (CAR) was first known as a virus receptor. Recently, it is also known to have tumor suppressive activity such as inhibition of cell proliferation, migration, and invasion. It is important to understand how CAR expression can be regulated in cancers. Based on an existence of putative Sp1 binding site within CAR promoter, we investigated whether indeed Sp1 is involved in the regulation of CAR expression. We observed that deletion or mutation of Sp1 binding motif (−503/−498) prominently impaired the Sp1 binding affinity and activity of CAR promoter. Histone deacetylase inhibitor (TSA) treatment enhanced recruitment of Sp1 to the CAR promoter in ChIP assay. Meanwhile, Sp1 binding inhibitor suppressed the recruitment. Exogenous expression of wild-type Sp1 increased CAR expression in CAR-negative cells; meanwhile, dominant negative Sp1 decreased the CAR expression in CAR-positive cells. These results indicate that Sp1 is involved in regulation of CAR expression

Effects of Rating Training on Inter-Rater Consistency for Developing a Dental Hygiene Clinical Rater Qualification System

We tried to develop itemized evaluation criteria and a clinical rater qualification system through rating training of inter-rater consistency for experienced clinical dental hygienists and dental hygiene clinical educators. A total of 15 clinical dental hygienists with 1-year careers participated as clinical examination candidates, while 5 dental hygienists with 3-year educations and clinical careers or longer participated as clinical raters. They all took the clinical examination as examinees. The results were compared, and the consistency of competence was measured. The comparison of clinical competence between candidates and clinical raters showed that the candidate group's mean clinical competence ranged from 2.96 to 3.55 on a 5-point system in a total of 3 instruments (Probe, Explorer, Curet), while the clinical rater group's mean clinical competence ranged from 4.05 to 4.29. There was a higher inter-rater consistency after education of raters in the following 4 items: Probe, Explorer, Curet, and insertion on distal surface. The mean score distribution of clinical raters ranged from 75% to 100%, which was more uniform in the competence to detect an artificial calculus than that of candidates (25% to 100%). According to the above results, there was a necessity in the operating clinical rater qualification system for comprehensive dental hygiene clinicians. Furthermore, in order to execute the clinical rater qualification system, it will be necessary to keep conducting a series of studies on educational content, time, frequency, and educator level

Isolation and Characterization of a Defensin-Like Peptide (Coprisin) from the Dung Beetle, Copris tripartitus

The antibacterial activity of immune-related peptides, identified by a differential gene expression analysis, was investigated to suggest novel antibacterial peptides. A cDNA encoding a defensin-like peptide, Coprisin, was isolated from bacteria-immunized dung beetle, Copris tripartitus, by using differential dot blot hybridization. Northern blot analysis showed that Coprisin mRNA was up-regulated from 4 hours after bacteria injection and its expression level was reached a peak at 16 hours. The deduced amino acid sequence of Coprisin was composed of 80 amino acids with a predicted molecular weight of 8.6 kDa and a pI of 8.7. The amino acid sequence of mature Coprisin was found to be 79.1% and 67.4% identical to those of defensin-like peptides of Anomala cuprea and Allomyrina dichotoma, respectively. We also investigated active sequences of Coprisin by using amino acid modification. The result showed that the 9-mer peptide, LLCIALRKK-NH2, exhibited potent antibacterial activities against Escherichia coli and Staphylococcus aureus

Dense Iron Ejecta and Core-collapse Supernova Explosion in the Young Supernova Remnant G11.2-0.3

We present the results of near-infrared spectroscopic observations of dense (\simgt 10$^3$ cm$^{-3}$) iron ejecta in the young core-collapse supernova remnant G11.2-0.3. Five ejecta knots projected to be close to its center show a large dispersion in their Doppler shifts: two knots in the east are blueshifted by more than 1,000 \kms, while three western knots have relatively small blueshifts of 20-60 \kms. This velocity discrepancy may indicate that the western knots have been significantly decelerated or that there exists a systematic velocity difference among the knots. One ejecta filament in the northwestern boundary, on the other hand, is redshifted by \simgt 200 \kms, while opposite filament in the southeastern boundary shows a negligible radial motion. Some of the knots and filaments have secondary velocity components, and one knot shows a bow shock-like feature in the velocity structure. The iron ejecta appear to be devoid of strong emission from other heavy elements, such as S, which may attest to the alpha-rich freezeout process in the explosive nucleosynthesis of the core-collapse supernova explosion close to its center. The prominent bipolar distribution of the Fe ejecta in the northwestern and southeastern direction, along with the elongation of the central pulsar wind nebula in the perpendicular direction, is consistent with the interpretation that the supernova exploded primarily along the northwestern and southeastern direction.Comment: To appear in ApJ Letter