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1.
Exp Mol Med ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38945956

RESUMEN

Angiotensin II (AngII) induces the contraction and proliferation of vascular smooth muscle cells (VSMCs). AngII activates phospholipase C-ß (PLC-ß), thereby inducing Ca2+ mobilization as well as the production of reactive oxygen species (ROS). Since contraction is a unique property of contractile VSMCs, signaling cascades related to the proliferation of VSMCs may differ. However, the specific molecular mechanism that controls the contraction or proliferation of VSMCs remains unclear. AngII-induced ROS production, migration, and proliferation were suppressed by inhibiting PLC-ß3, inositol trisphosphate (IP3) receptor, and NOX or by silencing PLC-ß3 or NOX1 but not by NOX4. However, pharmacological inhibition or silencing of PLC-ß3 or NOX did not affect AngII-induced VSMC contraction. Furthermore, the AngII-dependent constriction of mesenteric arteries isolated from PLC-ß3∆SMC, NOX1-/-, NOX4-/- and normal control mice was similar. AngII-induced VSMC contraction and mesenteric artery constriction were blocked by inhibiting the L-type calcium channel Rho-associated kinase 2 (ROCK2) or myosin light chain kinase (MLCK). The activation of ROCK2 and MLCK was significantly induced in PLC-ß3∆SMC mice, whereas the depletion of Ca2+ in the extracellular medium suppressed the AngII-induced activation of ROCK2, MLCK, and vasoconstriction. AngII-induced hypertension was significantly induced in NOX1-/- and PLC-ß3∆SMC mice, whereas LCCA ligation-induced neointima formation was significantly suppressed in NOX1-/- and PLC-ß3∆SMC mice. These results suggest that PLC-ß3 is essential for vascular hyperplasia through NOX1-mediated ROS production but is nonessential for vascular constriction or blood pressure regulation.

2.
Nucl Med Mol Imaging ; 58(4): 246-254, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38932756

RESUMEN

Purpose: This study assesses the clinical performance of BTXBrain-Amyloid, an artificial intelligence-powered software for quantifying amyloid uptake in brain PET images. Methods: 150 amyloid brain PET images were visually assessed by experts and categorized as negative and positive. Standardized uptake value ratio (SUVR) was calculated with cerebellum grey matter as the reference region, and receiver operating characteristic (ROC) and precision-recall (PR) analysis for BTXBrain-Amyloid were conducted. For comparison, same image processing and analysis was performed using Statistical Parametric Mapping (SPM) program. In addition, to evaluate the spatial normalization (SN) performance, mutual information (MI) between MRI template and spatially normalized PET images was calculated and SPM group analysis was conducted. Results: Both BTXBrain and SPM methods discriminated between negative and positive groups. However, BTXBrain exhibited lower SUVR standard deviation (0.06 and 0.21 for negative and positive, respectively) than SPM method (0.11 and 0.25). In ROC analysis, BTXBrain had an AUC of 0.979, compared to 0.959 for SPM, while PR curves showed an AUC of 0.983 for BTXBrain and 0.949 for SPM. At the optimal cut-off, the sensitivity and specificity were 0.983 and 0.921 for BTXBrain and 0.917 and 0.921 for SPM12, respectively. MI evaluation also favored BTXBrain (0.848 vs. 0.823), indicating improved SN. In SPM group analysis, BTXBrain exhibited higher sensitivity in detecting basal ganglia differences between negative and positive groups. Conclusion: BTXBrain-Amyloid outperformed SPM in clinical performance evaluation, also demonstrating superior SN and improved detection of deep brain differences. These results suggest the potential of BTXBrain-Amyloid as a valuable tool for clinical amyloid PET image evaluation.

3.
Mater Horiz ; 11(12): 2926-2936, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38567487

RESUMEN

Recently, inverted perovskite solar cells (PeSCs) have witnessed significant advancements; however, their long-term stability remains a challenge because of the oxidation of silver cathodes to form AgI by mobile iodides. To overcome this problem, we propose the integration of an electron-deficient naphthalene diimide-based zwitterion (NDI-ZI) as the cathode interlayer. Compared to the physical ion-blocking layer, it effectively captures ions by forming ionic bonds via electrostatic Coulombic interaction to suppress the migration of iodide and Ag ions. The NDI-ZI interlayer also suppresses the shunt paths and modulates the work function of the Ag electrode by forming interface dipoles, thereby enhancing charge extraction. FA0.85Cs0.15PbI3 based PeSCs incorporating NDI-ZI exhibited a noticeably high power conversion efficiency of up to 23.3% and outstanding stability, maintaining ∼80% of their initial performance over 1500 h at 85 °C and over 500 h under continuous 1-sun illumination. This study highlights the potential of a zwitterionic cathode interlayer in diverse perovskite optoelectronic devices, leading to their improved efficiency and stability.

4.
Brain Sci ; 14(2)2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38391707

RESUMEN

This research evaluated the modified RCTU score, derived from amyloid PET scans, for predicting the progression from amnestic Mild Cognitive Impairment (aMCI) to Alzheimer's Disease (AD). aMCI patients underwent baseline evaluations, including amyloid PET. AD conversion was identified through neuropsychological tests after observation. The RCTU was modified by segmenting frontal, parietal, and temporal lobes into left and right, resulting in seven areas. Scores from both modified and conventional RCTU were analyzed and compared. Among 45 patients, 12 progressed to AD (over 17.8 ± 6.8 months). AD converters showed higher scores in modified RCTU scores. Modified RCTU score had strong correlations with amyloid SUVR (r > 0.7). Modified RCTU sum score was the significant covariate of AD conversion. Modified RCTU could determine the asymmetry of amyloid deposits. We demonstrated that symmetric deposits of amyloid showed a higher risk for AD conversion when analyzed using modified RCTU. The modified RCTU score is a promising method for predicting AD conversion, correlating strongly with amyloid SUVR.

5.
Artículo en Inglés | MEDLINE | ID: mdl-37983071

RESUMEN

Perovskite defects are a major hurdle in the efficiency and stability of perovskite solar cells (PSCs). While various defect passivation materials have been explored, most are insulators that hinder charge transport. This study investigates the potential of two different π-conjugated polyelectrolytes (CPEs), MPS2-TEA and PCPDTBT2-TMA, as semiconducting additives in PSCs. The CPEs differ in electrical conductivity, offering a unique approach to bridge defect mitigation and charge carrier transport. Unlike previous uses of CPEs mainly as interlayers or charge transport layers, we explore their direct effect on defect passivation within a perovskite layer. Secondary ion microscopy reveals the even distribution of CPEs within the perovskite layer and their efficient defect passivation potential is studied through various spectroscopic analyses. Comparing MPS2-TEA and PCPDTBT2-TMA, we find MPS2-TEA to be superior in defect passivation. The highly conductive nature of PCPDTBT2-TMA due to self-doping diminishes its defect passivation ability. The negative sulfonate groups in the side chains of PCPDTBT2-TMA stabilize polarons, reducing defect passivation capability. Finally, the PSCs with MPS2-TEA achieve remarkable power conversion efficiencies (PCEs) of 22.7% for 0.135 cm2 and 20.0% for large-area (1 cm2) cells. Furthermore, the device with MPS2-TEA maintained over 87.3% of initial PCE after 960 h at continuous 1-sun illumination and 89% of PCE after 850 h at 85 °C in a nitrogen glovebox without encapsulation. This highlights CPEs as promising defect passivation additives, unlocking potential for improved efficiency and stability not only in PSCs but also in wider applications.

6.
Adv Sci (Weinh) ; 10(23): e2302906, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37271888

RESUMEN

Metal-halide perovskite nanocrystals (NCs) have emerged as suitable light-emitting materials for light-emitting diodes (LEDs) and other practical applications. However, LEDs with perovskite NCs undergo environment-induced and ion-migration-induced structural degradation during operation; therefore, novel NC design concepts, such as hermetic sealing of the perovskite NCs, are required. Thus far, viable synthetic conditions to form a robust and hermetic semiconducting shell on perovskite NCs have been rarely reported for LED applications because of the difficulties in the delicate engineering of encapsulation techniques. Herein, a highly bright and durable deep-blue perovskite LED (PeLED) formed by hermetically sealing perovskite NCs with epitaxial ZnS shells is reported. This shell protects the perovskite NCs from the environment, facilitates charge injection/transport, and effectively suppresses interparticle ion migration during the LED operation, resulting in exceptional brightness (2916 cd m-2 ) at 451 nm and a high external quantum efficiency of 1.32%. Furthermore, even in the unencapsulated state, the LED shows a long operational lifetime (T50 ) of 1192 s (≈20 min) in the air. These results demonstrate that the epitaxial and hermetic encapsulation of perovskite NCs is a powerful strategy for fabricating high-performance deep-blue-emitting PeLEDs.

7.
Adv Mater ; 35(24): e2210511, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36930970

RESUMEN

Further optimization of perovskite light-emitting diodes (PeLEDs) is impeded by crystal deformation caused by residual stress and defect formation with subsequent non-radiative recombination. Molecular additives for defect passivation are widely studied; however, the majority have insulating properties that hinder charge injection and transport. Herein, highly efficient green-emitting PeLEDs are reported by introducing semiconducting molecular additives (Fl-OEGA and Fl-C8A). Transmission electron microscopy shows that conjugated additives exist primarily at the grain boundaries of perovskite, and Kelvin probe force microscopy confirms that the variation in contact potential difference between grain boundaries and perovskite crystal domains is significantly reduced. The residual tensile stress is reduced by 13% and the activation energy for ion migration increases in the Fl-OEGA-treated perovskite film, compared to those of the film without additives. Compared to insulating 2,2'-(ethylenedioxy)diethylamine (EDEA), the introduction of semiconducting additives prevents a significant reduction in the charge-transport capability. Furthermore, the PeLEDs with Fl-OEGA show a negligible shift in the turn-on voltage and a significantly smaller decrease in the current density with increasing Fl-OEGA compared to the devices with EDEA. Finally, the 3D CsPbBr3 -PeLEDs show the highest external quantum efficiency of 21.3% by the incorporation of semiconducting Fl-OEGA as a new multifunctional additive.

8.
PLoS One ; 17(11): e0275233, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36327265

RESUMEN

The diagnosis of Alzheimer's disease (AD) needs to be improved. We investigated if hippocampal subfield volume measured by structural imaging, could supply information, so that the diagnosis of AD could be improved. In this study, subjects were classified based on clinical, neuropsychological, and amyloid positivity or negativity using PET scans. Data from 478 elderly Korean subjects grouped as cognitively unimpaired ß-amyloid-negative (NC), cognitively unimpaired ß-amyloid-positive (aAD), mild cognitively impaired ß-amyloid-positive (pAD), mild cognitively impaired-specific variations not due to dementia ß-amyloid-negative (CIND), severe cognitive impairment ß-amyloid-positive (ADD+) and severe cognitive impairment ß-amyloid-negative (ADD-) were used. NC and aAD groups did not show significant volume differences in any subfields. The CIND did not show significant volume differences when compared with either the NC or the aAD (except L-HATA). However, pAD showed significant volume differences in Sub, PrS, ML, Tail, GCMLDG, CA1, CA4, HATA, and CA3 when compared with the NC and aAD. The pAD group also showed significant differences in the hippocampal tail, CA1, CA4, molecular layer, granule cells/molecular layer/dentate gyrus, and CA3 when compared with the CIND group. The ADD- group had significantly larger volumes than the ADD+ group in the bilateral tail, SUB, PrS, and left ML. The results suggest that early amyloid depositions in cognitive normal stages are not accompanied by significant bilateral subfield volume atrophy. There might be intense and accelerated subfield volume atrophy in the later stages associated with the cognitive impairment in the pAD stage, which subsequently could drive the progression to AD dementia. Early subfield volume atrophy associated with the ß-amyloid burden may be characterized by more symmetrical atrophy in CA regions than in other subfields. We conclude that the hippocampal subfield volumetric differences from structural imaging show promise for improving the diagnosis of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Imagen por Resonancia Magnética , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Atrofia/patología , Péptidos beta-Amiloides , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología
9.
Exp Mol Med ; 54(8): 1133-1145, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35931736

RESUMEN

Retinal angiogenesis was delayed in VSMC-specific Akt1-deficient mice (Akt1∆SMC) but not in Akt2∆SMC mice. The proliferation of ECs, recruitment of pericytes, and coverage of VSMCs to the endothelium were defective in Akt1∆SMC. The silencing of Akt1 in VSMCs led to the downregulation of angiopoietin 1 (Ang1) and the upregulation of Ang2. The activation of Notch3 in VSMCs was significantly reduced in the retinas of Akt1∆SMC mice. Silencing Akt1 suppressed the activation of Notch3. Moreover, the silencing of Notch3 downregulated Ang1, whereas the overexpression of Notch3 intracellular domain (NICD3) enhanced Ang1 expression. The nuclear localization and transcriptional activity of yes-associated protein (YAP) were affected by the expression level of Akt1. Silencing YAP downregulated Ang2 expression, whereas overexpression of YAP showed the opposite results. Ang1 antibody and Ang2 suppressed endothelial sprouting of wild-type aortic tissues, whereas the Ang2 antibody and Ang1 facilitated the endothelial sprouting of aortic tissues from Akt1∆SMC mice. Finally, severe hemorrhage was observed in Akt1∆SMC mice, which was further facilitated under streptozotocin (STZ)-induced diabetic conditions. Therefore, the Akt1-Notch3/YAP-Ang1/2 signaling cascade in VSMCs might play an essential role in the paracrine regulation of endothelial function.


Asunto(s)
Angiopoyetina 1/metabolismo , Angiopoyetina 2/metabolismo , Músculo Liso Vascular , Proteínas Proto-Oncogénicas c-akt/metabolismo , Angiopoyetina 1/genética , Animales , Ratones , Miocitos del Músculo Liso/metabolismo , Pericitos/metabolismo , Transducción de Señal
10.
Psychiatry Investig ; 19(5): 394-400, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35620825

RESUMEN

OBJECTIVE: Baseline amyloid burden in mild cognitive impairment (MCI) has been linked to conversion to Alzheimer's disease (AD), but the comparison of baseline and longitudinal changes in amyloid burden for predicting AD remains unresolved. The objectives of this study aimed to compare the prognostic ability of baseline and longitudinal changes in amyloid burden in MCI patients. METHODS: Seventy-five individuals with MCI were recruited and examined annually by clinical interviews for a mean follow-up of 24 months (range, 11.6-42.0). [18F]Florbetaben positron emission tomography (PET) scans were performed. T1-weighted 3D volumes were acquired for co-registration, and to define regions of interest. We examined whether baseline and longitudinal amyloid burden changes can improve AD conversion by Cox proportional hazard model analysis and receiver operating characteristic (ROC) curve analysis. RESULTS: Cox proportional hazards model analysis showed that baseline amyloid burden was significantly associated with increased risk of conversion to AD (hazard ratio [HR]=10.0; 95% confidence interval [CI], 1.15-85.39; p=0.04), but longitudinal amyloid burden changes was not (HR=0.2; 95% CI, 0.02-1.18; p=0.07). When predicting AD, longitudinal amyloid burden changes had better ROC accuracy of 65.2% (95% CI, 48.4-82.0) than baseline amyloid burden of 59.6% (95% CI, 40.3-79.0), without statistical significance in pairwise comparison. CONCLUSION: A single baseline amyloid PET could be sufficient in the prediction of AD conversion in MCI.

11.
Small ; 18(5): e2104933, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34846779

RESUMEN

π-Conjugated polyelectrolytes (CPEs) have been studied as interlayers on top of a separate hole transport layer (HTL) to improve the wetting, interfacial defect passivation, and crystal growth of perovskites. However, very few CPE-based HTLs have been reported without rational molecular design as ideal HTLs for perovskite solar cells (PeSCs). In this study, the authors synthesize a triphenylamine-based anionic CPE (TPAFS-TMA) as an HTL for p-i-n-type PeSCs. TPAFS-TMA has appropriate frontier molecular orbital (FMO) levels similar to those of the commonly used poly(bis(4-phenyl)-2,4,6-trimethylphenylamine) (PTAA) HTL. The ionic and semiconducting TPAFS-TMA shows high compatibility, high transmittance, appropriate FMO energy levels for hole extraction and electron blocking, as well as defect passivating properties, which are confirmed using various optical and electrical analyses. Thus, the PeSC with the TPAFS-TMA HTL exhibits the best power conversion efficiency (PCE) of 20.86%, which is better than that of the PTAA-based device (PCE of 19.97%). In addition, it exhibits negligible device-to-device variations in its photovoltaic performance, contrary to the device with PTAA. Finally, a large-area PeSC (1 cm2 ) and mini-module (3 cm2 ), showing PCEs of 19.46% and 18.41%, respectively, are successfully fabricated. The newly synthesized TPAFS-TMA may suggest its great potential as an HTL for large-area PeSCs.


Asunto(s)
Energía Solar , Compuestos de Calcio/química , Óxidos/química , Polielectrolitos , Titanio
12.
ACS Appl Mater Interfaces ; 13(51): 61454-61462, 2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-34913684

RESUMEN

In this study, we demonstrated two deep-blue TADF emitters, BO-tCzPhICz and BO-tCzDICz, for solution-processable thermally activated delayed fluorescence organic light-emitting diodes (TADF-OLEDs). They were synthesized by employing an organoboron acceptor and 9-(3,6-di-tert-butyl-9H-carbazol-9-yl)-5-phenyl-5,12-dihydroindolo[3,2-a]carbazole (tCzPhICz) and 12-(3,6-di-tert-butyl-9H-carbazol-9-yl)-15H-diindolo[2,3-b:1',2',3'-lm]carbazole (tCzDICz) as bulky aryl-annulated [3,2-a] carbazole donors, respectively. Both emitters showed sufficient solubility in organic solvents, narrow deep-blue emission, and small energy difference (ΔEST) between singlet and triplet states, which can be applied to solution-processable deep-blue TADF-OLEDs. Solution-processed OLEDs exploiting these TADF emitters displayed deep-blue electroluminescence with CIEy <0.1, and high external quantum efficiencies of 17.8 and 14.8% were observed for BO-tCzPhICz and BO-tCzDICz, respectively. The emitter bearing bulky ICz-based donating units shows highly promising potential for high-efficiency solution-processable deep-blue TADF-OLEDs.

13.
ACS Appl Mater Interfaces ; 13(41): 49076-49084, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34628848

RESUMEN

Three V-shaped host molecules with a cyclohexane linker were successfully synthesized for thermally activated delayed fluorescence organic light-emitting diodes (TADF-OLEDs). The unipolar host molecules, BBCzC and BTDC, contained two 9-phenyl-9H-3,9'-bicarbazole (PBCz) moieties and two 2,12-di-tert-butyl-7-phenyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene (PDBNA) moieties, respectively. BCzTC, a bipolar host molecule, consisted of a donor unit, PBCz, and an acceptor unit, PDBNA, connected by a cyclohexane linker. Three host molecules showed good solubility in various organic solvents, making them suitable for solution processing. Among the solution-processed green TADF-OLEDs using three host molecules and a green TADF emitter, the one with BCzTC showed the highest external quantum efficiency of up to 30% with a high power efficiency of 71 lm W-1 and a current efficiency of 102 cd A-1. Compared with BBCzC and BTDC, BCzTC exhibited a relatively high photoluminescence quantum yield (PLQY), an excellent balance in hole and electron transport properties in the emitting layer, and more efficient energy transfer to the emitter, giving such an excellent device performance.

14.
Clin Endocrinol (Oxf) ; 95(6): 901-908, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34185324

RESUMEN

OBJECTIVE: The aim of this study is to investigate whether the number of metastatic lymph nodes (LNs) could be used as a basis in the radioactive iodine (RAI) dose selection for patients with papillary thyroid carcinoma (PTC). PATIENTS: A total of 595 patients with PTC who received first RAI therapy after total or near-total thyroidectomy and had no evidence of disease in treatment response assessment were retrospectively enroled from five hospitals. The patients were classified into two subgroups based on the number of metastatic LNs (>5). The multivariate Cox-proportional hazard model was performed to identify the significant factors for recurrence prediction in each group as well as all enroled patients. RESULTS: Overall, 22 (3.7%) out of 595 patients had the recurrent disease during the follow-up period. The number of metastatic LNs (>5) was only a significant factor for recurrence prediction in all enroled patients (odds ratio: 7.834, p < .001). In the subgroup with ≤5 metastatic LNs, the presence of extrathyroidal extension was only associated with recurrence (odds ratio: 7.333, p = .024) in multivariate analysis. RAI dose was significantly associated with recurrence rate in which the patients with high-dose RAI (3.7 GBq or higher) had less incidence of recurrence than those with low-dose RAI (1.11 GBq) in the subgroup with more than five metastatic LNs (odds ratio: 6.533, p = .026). CONCLUSIONS: High-dose RAI (≥3.7 GBq) therapy significantly lowered the recurrence rate in patients with more than five metastatic LNs. Therefore, RAI dose should be determined based on the number of metastatic LNs as well as conventional risk factors.


Asunto(s)
Carcinoma Papilar , Neoplasias de la Tiroides , Carcinoma Papilar/radioterapia , Carcinoma Papilar/cirugía , Humanos , Radioisótopos de Yodo/uso terapéutico , Ganglios Linfáticos , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Cáncer Papilar Tiroideo/cirugía , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Tiroidectomía
15.
ACS Appl Mater Interfaces ; 13(22): 26227-26236, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34036782

RESUMEN

A series of green-emitting fluorophores based on a tetra-azaacene core is synthesized by introducing nitrile substituents at different positions. Their molecular structure-optical property relationship [i.e., vibronic transitions in photoluminescence (PL) and electroluminescence (EL) spectra] is investigated to obtain a sharp emission where the vibronic peak ν0-0 should be intensified by suppressing ν0-n (n = 1, 2, 3...) transitions. The intensity ratios (I0-1/I0-0) of the ν0-1 and ν0-0 vibronic transitions in the PL spectra of DBBNP, DBBNP2CN1, and DBBNP2CN2 in hexane are 1.13, 0.80, and 0.67, respectively. Theoretical calculations explain that the CN substitution at positions 8 and 13 in DBBNP2CN2 induces a uniform charge distribution and reduces the Huang-Rhys factors (HRFs) of the vibrational normal modes coupled to the electronic transition. The organic light-emitting diode (OLED) fabricated with DBBNP2CN2 shows a narrower green EL emission at 518 nm with a smaller bandwidth (50 nm) than those of devices adopting DBBNP or DBBNP2CN1. The careful modification of the molecular structures and positions of substituents enables us to reduce the HRFs of vibrations to achieve a narrow emission bandwidth with decreased I0-1/I0-0, which suggests a design strategy to develop narrowband organic fluorophores to improve the color purity for wide-gamut OLED displays.

16.
J Lipid Atheroscler ; 10(1): 99-110, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33537257

RESUMEN

OBJECTIVE: The purpose of this study is to examine the effect of high mobility group AT-hook 1 (HMGA1) on the phenotyptic change of vascular smooth muscle cells (VSMCs). METHODS: Gene silencing and overexpression of HMGA1 were introduced to evaluate the effect of HMGA1 expression on the phenotypic change of VSMCs. Marker gene expression of VSMCs was measured by promoter assay, quantitative polymerase chain reaction, and western blot analysis. Common left carotid artery ligation model was used to establish in vivo neointima formation. RESULTS: HMGA1 was expressed strongly in the synthetic type of VSMCs and significantly downregulated during the differentiation of VSMCs. Silencing of HMGA1 in the synthetic type of VSMCs enhanced the expression of contractile marker genes thereby enhanced angiotensin II (Ang II)-dependent contraction, however, significantly suppressed proliferation and migration. Stimulation of contractile VSMCs with platelet-derived growth factor (PDGF) enhanced HMGA1 expression concomitant with the downregulation of marker gene expression which was blocked significantly by the silencing of HMGA1. Silencing of HMGA1 retained the Ang II-dependent contractile function, which was curtailed by PDGF stimulation, however, overexpression of HMGA1 in the contractile type of VSMCs suppressed marker gene expression. Proliferation and migration were enhanced significantly by the overexpression of HMGA1. Furthermore, the Ang II-dependent contraction was reduced significantly by the overexpression of HMGA1. Finally, the expression of HMGA1 was enhanced significantly in the ligated artery, especially in the neointima area. CONCLUSION: HMGA1 plays an essential role in the phenotypic modulation of VSMCs. Therefore, paracrine factors such as PDGF may affect vascular remodeling through the regulation of HMGA1.

17.
ACS Nano ; 14(10): 13246-13255, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-32910640

RESUMEN

A series of poly(fluorene-co-phenylene)-based anionic conjugated polyelectrolytes (CPEs) are prepared with varying sizes of counterions (tetramethylammonium, tetraethylammonium, and tetrabutylammonium (TBA+)) and studied as a hole-transporting layer (HTL) for sky-blue-emissive perovskite light-emitting diodes (PeLEDs). Ionic CPE HTLs improve the wettability, compatibility, and nucleation of perovskite crystals at interfaces, enabling highly crystalline perovskite crystal growth with enhanced light-emitting properties. By incorporating the CPE HTLs containing bulky TBA+ counterions (MPS2-TBA) in place of PEDOT:PSS, the decreased phonon-electron coupling and increased exciton binding energy in perovskites are measured by temperature-dependent photoluminescence (PL) measurements. By increasing the size of counterions in CPE interlayers, the PL intensities and lifetimes of perovskite films increase. Through space-charge-limited current measurements, the lowest trap density is measured in the perovskite film on MPS2-TBA, emphasizing a critical role of larger counterions. Using density functional theory, MPS2-TBA is calculated to show the strongest adsorption affinity toward the interstitial defect of lead ions, explaining its pronounced interfacial defect passivation. The counterion size in CPE interlayers is interpreted as a main factor to determine the adsorption affinity onto perovskite, which determines the interacted area as noncovalent adsorption occurs. Finally, the sky-blue-emissive quasi-2D PeLED with MPS2-TBA shows the highest luminance efficiency (a peak EQE of 2.6% at 489 nm) and significantly improved spectral stability.

18.
Am J Case Rep ; 21: e923406, 2020 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-32641680

RESUMEN

BACKGROUND Osmotic demyelination syndrome (ODS) is an uncommon neurological disorder. Until the mid-1980s, the mortality rate was 90-100%, but more than half of patients now have a good prognosis. Early suspicion of ODS is important. However, radiologic findings of ODS are variable and scintigraphy findings have not been reported. CASE REPORT A 38-year-old man with alcohol abuse history was admitted due to electrolyte imbalance. On the 10th day of his hospital stay, he had a generalized tonic-clonic seizure. Brain perfusion SPECT showed asymmetrically hyperperfused and hypoperfused lesions. Brain MRI revealed diffuse T2 hyperintensity with mild diffusion restriction in the pons and hyperperfused lesions on brain SPECT. He was treated based on the diagnosis of hyponatremia and osmotic demyelination. After treatment, the asymmetric hyperperfusion was decreased. MRI showed that the cortical hyperintensity had resolved, with encephalomalacic change shown in the pons. CONCLUSIONS To the best of our knowledge, this is the first report showing changes in brain perfusion SPECT and MRI in an ODS patient with a seizure. This case report may be helpful to neurologists, radiologists, and nuclear physicians.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Mielinólisis Pontino Central/diagnóstico por imagen , Convulsiones/etiología , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Alcoholismo/complicaciones , Electrólitos/uso terapéutico , Fluidoterapia , Humanos , Hiponatremia/diagnóstico , Hiponatremia/terapia , Masculino , Mielinólisis Pontino Central/terapia , Convulsiones/prevención & control , Vitaminas/uso terapéutico , Desequilibrio Hidroelectrolítico/complicaciones , Desequilibrio Hidroelectrolítico/terapia
19.
J Alzheimers Dis ; 75(3): 949-958, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32390627

RESUMEN

BACKGROUND: Cerebrospinal fluid (CSF) amyloid-ß1-42 (Aß1-42), total tau protein (t-Tau), and phosphorylated Tau (p-Tau) are ATN biomarkers for Alzheimer's disease (AD) and reflect pathogenic changes in the brain. CSF biomarkers of AD are considered for inclusion in the diagnostic criteria for research and clinical purposes to reduce the uncertainty of clinical diagnosis and to distinguish among AD stages. OBJECTIVE: This study aims to compare two commercially available analytical platforms with respect to accuracy and the potential for early diagnosis of AD. METHODS: A total of 211 CSF samples from healthy control (HC) and AD subjects were analyzed using two analytical platforms, INNOTEST ELISA and INNOBIA AlzBio3 xMAP kits. The accuracy of diagnosis and AUC values distinguishing study groups were compared between the two analytical platforms. RESULTS: The absolute values for Aß1-42, t-Tau, and p-Tau181 levels differed between the two platforms. The Aß1-42 levels decreased, while t-Tau and p-Tau levels increased according to the AD stages. The AUC of Aß1-42 and t-Tau, which distinguish the early stages of AD (preclinical and prodromal AD), were similar between the two platforms, whereas there were significant differences in p-Tau AUC values. CSF p-Tau using the INNOBIA was highly accurate for distinguishing both preclinical AD (AUC = 0.826, cut-off score≥38.89) and prodromal AD (AUC = 0.862, cut-off score≥41.88) from HC. CONCLUSION: The accuracy of CSF p-Tau levels in the preclinical and prodromal AD is higher for the INNOBIA than the INNOTEST, and the early stage AD can be accurately distinguished from HC.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/diagnóstico , Encéfalo/patología , Inmunoensayo/métodos , Anciano , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/líquido cefalorraquídeo , Tomografía de Emisión de Positrones , Curva ROC , Proteínas tau/líquido cefalorraquídeo
20.
J Anesth ; 34(3): 352-357, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32100118

RESUMEN

PURPOSE: Retinopathy of prematurity (ROP) is an ocular disorder that primarily occurs in premature infants and is the most common cause of vision impairment. This study examined the effect of desflurane on angiogenesis in a mouse model of oxygen-induced retinopathy (OIR). METHODS: Mice were randomly allocated to the control (C), ROP control (Rc), or ROP with desflurane exposure (Rd) group. To induce ROP, 7-day-old mice were exposed to 75% oxygen in a chamber for 5 days [postnatal days (P) 7-12], and thereafter returned to room air. Age-matched mice exposed to room air formed the C group. The Rd group was exposed to 8% desflurane for 2 h on P12, P13, and P14 with 40% oxygen. To observe changes in angiogenesis of the retina, mice were sacrificed at P16. RESULTS: The ratio of avascular area/total retinal area was not changed significantly in the Rd group, compared to the Rc group. The expression of endothelial growth factor A (VEGF-A) and hypoxia inducible factor-1α (HIF-1α) in the Rd group and Rc group was not significantly different. CONCLUSIONS: Desflurane does not have a significant influence on retinal angiogenesis via HIF-1α and VEGF-A expression in the OIR mouse model. However, these findings are not directly applicable to premature infants, and it is thus necessary to perform further studies to determine the effect of desflurane on angiogenesis.


Asunto(s)
Oxígeno , Neovascularización Retiniana , Animales , Animales Recién Nacidos , Desflurano , Modelos Animales de Enfermedad , Humanos , Recién Nacido , Ratones , Ratones Endogámicos C57BL , Retina , Neovascularización Retiniana/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular
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