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Lowering the Schottky barrier at the metal-semiconductor interface remains a stern challenge in the field of field-effect transistors. Herein, an in-depth investigation was conducted to explore the formation mechanism of the Schottky barrier via interlayer distance and external electric field, utilizing the first-principles approach. Attributed to the vertical asymmetric structure of B2P6, ohmic contact forms at the interface of a graphene/B2P6(001) heterostructure, and an n-type Schottky contact with a Schottky barrier of 0.51 eV forms at the interface of a graphene/B2P6(001Ì) heterostructure. Furthermore, the Schottky barrier height and the contact type can be changed by adjusting the interlayer spacing or applying an electric field along the Z direction. A high carrier concentration of 4.65 × 1013 cm-2 is obtained in the graphene/B2P6(001) heterostructure when an external electric field of 0.05 V Å-1 is applied. Verifiably, alterations in the energy band structure are attributed to the redistribution of charges at the interface. The new findings indicate that GR/B2P6 heterostructures are a key candidate for next-generation Schottky field-effect transistor development.
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We propose and experimentally demonstrate a novel, to the best of our knowledge, private correlated random bit generation (CRBG) scheme based on commonly driven induced synchronization of two wideband physical entropy sources, which employs an open-loop distributed feedback laser followed by a hybrid electro-optic nonlinear transformation hardware module for effective bandwidth expansion and privacy enhancement. A Mach-Zehnder interferometer followed by an electro-optic self-feedback phase modulation loop as well as a dispersion element are constructed as a private hardware module to perform post-processing and nonlinear transformation of the synchronized signal. A record high rate of 5.2-Gb/s CRBG is successfully achieved between two synchronized wideband physical entropy sources with an enhanced entropy source rate and hardware key space. The demonstrated scheme may provide a new way for CRBG in future high speed secure communication systems.
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WHAT IS KNOWN AND OBJECTIVE: Low treatment persistence and adherence in patients with dementia results in a rapid loss of disease control. This pilot study evaluated the impact of pharmacist-provided caregiver counselling on treatment persistence, adherence, quality of life (QoL) in patients with dementia, as well as caregiver's knowledge of dementia, and caregiver burden. METHODS: This prospective, randomized controlled study was performed at a hospital-based pharmacist-managed clinic from December 2017 to December 2019. Patients with mild-to-moderate Alzheimer's disease (AD), initiating cholinesterase inhibitors within 3 months, and coming with their caregivers were included and randomized 1:1 to intervention or control group. The intervention group received pharmacist counselling and education sheets about AD, whereas the control group only received standard of care. Patients' treatment persistence and adherence were assessed at months 3, 6, 9, and 12; QoL, and caregiver burden were assessed at baseline and month 12. Caregiver's knowledge of dementia was assessed at baseline and 2 weeks after counselling in the intervention group. Nonparametric statistics and generalized estimating equation models were used for statistical analysis. RESULTS AND DISCUSSION: A total of 40 patients and 40 caregivers were included, with 20 pairs for each group. One-year medication persistence (16/20 vs. 16/20) and adherence rates (87%-99%) were high in both groups without significant differences. Dementia knowledge scores improved significantly after counselling in the intervention group (77.5 vs. 95.8, p < 0.01). Although the change of caregiver burden was non-significant between groups, the score decreased in the intervention group (-0.89; p = 0.78) but increased in the control group (+6.01; p = 0.07). WHAT IS NEW AND CONCLUSION: In this pilot study, pharmacist's counselling for patients with dementia and their caregivers is feasible and can enhance caregiver knowledge of dementia. Further study with larger scale is needed to confirm the impact on these outcomes.
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Enfermedad de Alzheimer , Cuidadores , Humanos , Calidad de Vida , Proyectos Piloto , Farmacéuticos , Estudios Prospectivos , Cumplimiento de la Medicación , ConsejoRESUMEN
Bismuth-antimony alloy is considered as a promising potassium ion battery anode because of its combination of the high theoretical capacity of antimony and the excellent rate capacity of bismuth. However, the large volume change and sluggish reaction kinetic upon cycling have triggered severe capacity fading and poor rate performance. Herein, a nanoconfined BiSb in tremella-like carbon microspheres (BiSb@TCS) are delicately designed to address these issues. As-prepared BiSb@TCS renders an outstanding potassium-storage performance with a reversible capacity of 181 mAh g-1 after ultralong 5700 cycles at a current density of 2 A g-1 , and an excellent rate capacity of 119.3 mAh g-1 at 6 A g-1 . Such a superior performance can be ascribed to the delicate microstructure. The self-assembled carbon microspheres can strengthen integral structure and effectively accommodate the volume expansion of BiSb nanoparticles, and 2D carbon nanowalls in carbon microspheres can provide fast ion/electron diffusion dynamic. Theoretical calculation also suggests a thermodynamic feasibility of alloyed BiSb nanoparticles for storing potassium ion. Such a work shows that BiSb@TCS possesses a great potential to be a high-performance anode of potassium ion batteries. The rational designing of multiscaled structure would be instructive to the exploitation of other energy-storage materials.
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An understanding of the high photocatalytic performance reported for MoS2/BiOI nanocomposite is far from satisfactory. Here, the interfacial interaction and electronic properties of a MoS2/BiOI heterostructure were investigated systematically for the first time by first-principle calculations incorporating a semi-empirical dispersion-correction scheme. Our results confirm the reasonable existence of van der Waals interactions and a favorable Z-scheme mechanism, based on the typical interfacial cohesive energy and the energy level lineup at the interface. Analyzing the charge density differences and work functions, the built-in electric field is formed along the direction from MoS2 to BiOI after the interface equilibrium, and facilitates the separation of photoinduced electron-hole pairs in the interface. Additionally, it can be inferred that the incorporation of MoS2 into BiOI increases the carrier mobility and improves light harvesting, in agreement with the previously reported experimental data. Our work provides an insight into the mechanism of the enhanced visible-light photocatalytic activity of a MoS2/BiOI heterostructure, and helps to design other new heterostructure combinations.
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The manipulation of the constituents of novel hetero-photocatalysts is an effective method for improving photocatalytic efficiency, but a theoretical understanding of the relationship between interlayer interaction and photocatalytic activity is still lacking. Herein, the interfacial interactions and electronic properties of MoS2/graphene oxide (GO) heterojunctions with various O concentrations were explored systematically by first-principles calculations. The results indicate that MoS2 and GO can form a stable van der Waals heterojunction, and enhance the built-in internal electric field from GO to the MoS2 surface with the increase in O concentration after interfacial equilibrium. It is inferred that the photogenerated electrons and holes naturally accumulate in the conduction band of GO and the valence band of MoS2, respectively, under the built-in internal electric field driving, indicating the formation of direct Z-scheme heterojunctions. In addition, a red shift of the light absorption edge and the shift up of the conduction band edge of MoS2/GO heterojunctions are observed with an increase in O concentration. It can be concluded that the O atom plays a crucial role in the energy band alignment of MoS2/GO heterojunctions for the improvement of photocatalytic performance. These results are beneficial to understand and design layered MoS2/GO photocatalytic systems or as cocatalysts with other semiconductors.
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AIMS: This study aimed to investigate whether cabotegravir (CAB), an integrase inhibitor in development for treatment and prevention of human immunodeficiency virus-1, influences the pharmacokinetics (PK) of a levonorgestrel (LNG) and ethinyl oestradiol (EO)-containing oral contraceptive (OC) in healthy women. METHODS: In this open-label, fixed-sequence crossover study, healthy female subjects received LNG 0.15 mg/EO 0.03 mg tablet once daily Days 1-10 alone and with oral CAB 30 mg once daily Days 11-21. At the end of each treatment period, subjects underwent predose sampling for concentrations of follicle-stimulating hormone, luteinizing hormone, and progesterone and serial PK sampling for plasma LNG, EO, and CAB concentrations. RESULTS: Twenty women were enrolled, and 19 completed the study. One subject was withdrawn due to an adverse event unrelated to study medications. Geometric least squares mean ratios (90% confidence interval) of LNG + CAB vs. LNG alone for LNG area under the plasma concentration-time curve over the dosing interval of duration τ and maximum observed plasma concentration were 1.12 (1.07-1.18) and 1.05 (0.96-1.15), respectively. Geometric least squares mean ratio (90% confidence interval) of EO + CAB vs. EO alone for EO area under the plasma concentration-time curve over the dosing interval of duration τ and maximum observed plasma concentration were 1.02 (0.97-1.08) and 0.92 (0.83-1.03), respectively. Steady-state CAB PK parameters were comparable to historical values. There was no apparent difference in mean luteinizing hormone, follicle-stimulating hormone, and progesterone concentrations between periods. No clinically significant trends in laboratory values, vital signs, or electrocardiography values were observed. CONCLUSIONS: Repeat doses of oral CAB had no significant effect on LNG/EO PK or pharmacodynamics, which supports CAB coadministration with LNG/EO OCs in clinical practice.
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Anticonceptivos Orales Combinados/farmacología , Etinilestradiol/farmacología , Inhibidores de Integrasa VIH/farmacología , Levonorgestrel/farmacología , Piridonas/farmacología , Administración Oral , Adulto , Área Bajo la Curva , Estudios Cruzados , Combinación de Medicamentos , Interacciones Farmacológicas , Femenino , Hormona Folículo Estimulante Humana/sangre , Voluntarios Sanos , Humanos , Hormona Luteinizante/sangre , Progesterona/sangre , Adulto JovenRESUMEN
BACKGROUND/PURPOSE: To determine whether dual-phase 18F-florbetapir positron emission tomography imaging with perfusion-like and amyloid deposition information can distinguish among primary progressive aphasia (PPA), Alzheimer's disease (AD), and healthy controls (HCs). METHODS: Patients diagnosed with PPA, including four semantic dementia (SD) and two progressive nonfluent aphasia (PNFA), as well as one logopenic variant (LV) of PPA, were studied. All PPA patients, and age-/sex-matched patients with probable AD (n=8) and HCs (n=8) were subjected to dual-phase 18F-florbetapir imaging. Atlas-based quantitative volumes of interest (VOIs) analysis for six cortical areas and whole cerebellum was performed. The standardized uptake value ratios were calculated by normalizing the dual-phase-integrated activities of the six VOIs to whole cerebellum counts. RESULTS: Early phase 18F-florbetapir image showed significantly lower global perfusion index in six PPA patients as compared with HCs. According to VOI analysis, the hypoperfusion lesions were identified in the frontal, anterior cingulate, parietal, precuneus, and temporal regions. Similar findings were confirmed by voxel-base image comparison. 18F-florbetapir late-phase image showed significantly increased amyloid burden in the global cortex index and all six brain regions of eight AD and LV patients when compared with the other six PPA patients and eight HCs. There was no apparent uptake of amyloid tracer in both six PPA patients and eight HCs. CONCLUSION: Dual-phase 18F-florbetapir images of six PPA (SD and PNFA) patients showed hypoperfusion in the frontotemporal cortex, and little global amyloid uptake, which may be a distinct image pattern for differentiation among HC, AD, and PPA patients.
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Enfermedad de Alzheimer/diagnóstico por imagen , Afasia Progresiva Primaria/diagnóstico por imagen , Encéfalo/patología , Tomografía de Emisión de Positrones , Anciano , Compuestos de Anilina/administración & dosificación , Encéfalo/diagnóstico por imagen , Estudios de Casos y Controles , Glicoles de Etileno/administración & dosificación , Femenino , Fluorodesoxiglucosa F18/administración & dosificación , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , TaiwánRESUMEN
Laser sources with a controllable flexible wavelength have found widespread applications in optical fiber communication, optical sensing, and microscopy. Here, we report a tunable mode-locked fiber laser using a graphene-based saturable absorber and a tapered mirror as an end mirror in the cavity. The phase layer in the mirror is precisely etched by focused ion beam (FIB) milling technology, and the resonant wavelength of the mirror shifts correspond to the different etch depths. By scanning the tapered mirror mechanically, the center wavelength of a mode-locked fiber laser can be continuously tuned from 1562 to 1532 nm, with a pulse width in the sub-ps level and repetition rate of 27 MHz.
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The lab made an effort to prepare some biological active cantharidinimines by heating the reactant 1 and 2a-g, 5h-i and 7j-r amines to suitable temperature with ethanol to provide 18 N-thiazolyl-, sulfanyl-, aminopyridyl-, bromopyridyl-, alkylpyridyl- and hydroxypyridylcantharidinimines 3a-g, 4a-c, 6h-i and 8j-r in yield of 4-77% (Chart 1). These cantharidinimine derivatives were tested for their capabilities to suppress growth of the human carcinoma cell lines, HL-60, MCF7, Neuro-2a and A549, because the incidence rate is more prominent in Asian countries than western countries. Compounds 3c-d and 6h-i were found to have some antitumor activity in HL-60 but less activity in MCF cell and compounds 8j-l displayed some inhibition effects to A549 cell line, but less effect to Neuro-2a cell line. Compounds 8m-r had no cytotoxic effect against both cell lines. The cytotoxic effects of these cantharidinimine compounds seemed to be better than the cantharidinimide compounds which we had mentioned several years ago.
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Antineoplásicos/química , Antineoplásicos/farmacología , Cantaridina/análogos & derivados , Cantaridina/farmacología , Animales , Antineoplásicos/síntesis química , Cantaridina/síntesis química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células HL-60 , Humanos , Concentración 50 Inhibidora , Insectos/química , Células MCF-7 , Neoplasias/tratamiento farmacológicoRESUMEN
PURPOSE: Symptoms and medication use in patients with Parkinson's disease (PD) affect the quality of life of patients and caregivers, yet prior research seldom focused on their experiences with medications. This study explored comprehensive living and medication experience from patients with PD and their caregivers. METHODS: Patients diagnosed with PD for ≥2 years, with or without their caregivers, were recruited from an outpatient clinic in Taiwan. Semi-structured in-depth interviews were conducted based on the Common Sense Model. A qualitative content analysis was used to identify salient themes from verbatim transcripts. RESULTS: In total, 15 patients and eight caregivers were interviewed. Five themes were derived: (1) symptoms and help-seeking behaviours before a diagnosis, (2) emotional impacts and life adaptations after a PD diagnosis, (3) life affected by medications, (4) experiences of caregivers in taking care of PD patients, and (5) communication between doctors and patients. CONCLUSIONS: Patients frequently adjusted their daily schedules to live with PD and the medication side effects. Caregivers struggle to overcome caring burdens and to stay positive to support patients. More attention on providing medication information, mental support, and communication between stakeholders is needed to improve the quality of life of patients and caregivers.
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Enfermedad de Parkinson , Médicos , Cuidadores , Comunicación , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Calidad de VidaRESUMEN
Delafossite CuFeO2 has recently attracted considerable attention because of its complex phase transitions and practical applications. A thorough understanding of the optical properties of CuFeO2 is essential for its further exploration. In this paper, we investigated the temperature-dependent optical properties of CuFeO2 single crystals through Raman scattering spectroscopy and spectroscopic ellipsometry. The room temperature Raman scattering spectrum exhibited six phonon modes at approximately 352, 509, 692, 1000, 1052, and 1171 cm-1. Upon cooling across 11 K, which is the rhombohedral to monoclinic structural phase transition temperature, a softening of the E g-symmetry 352 cm-1 mode and a hardening of the A 1g-symmetry 692 cm-1 mode were observed. Moreover, analysis of the temperature-dependent real part of the dielectric function and direct band gap revealed anomalies at 11 K. These results demonstrate a profound connection between the structural phase transition, lattice dynamics, and electronic structure of CuFeO2 and provide key information for CuFeO2-based device design and fabrication.
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The two-dimensional semiconductor photocatalytic material has excellent photocatalytic H2 evolution activity. In order to further improve the hydrogen production activity of g-C3N4, this study improved the preparation process of g-C3N4 and obtained a new photocatalyst (name H-CN) with a higher absorption range, larger specific surface area, and faster hydrogen production activity. Compared with the originally prepared g-C3N4, the H-CN absorption range has been improved, and the utilization of visible light has reached 650 nm. When the doping amount of Pt cocatalyst was 1.0 wt%, the H-CN demonstrates excellent photocatalytic hydrogen production activity, with a hydrogen production rate of 4.3 mmol h-1·g-1, which was 7.0 times higher than that pure 1.0 wt% Pt/g-C3N4. The fluorescence spectroscopy of H-CN showed better separation of carriers and longer lifetime. This study has guiding significance for the preparation of subsequent ultra-thin nanosheet photocatalysts and the establishment of high-efficiency photocatalytic systems.
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A strategy is proposed for modifying BiVO4 photoanode with CoNiO2 as a novel water oxidation cocatalyst to enhance PEC water splitting performance. The results show that CoNiO2 has the following functions: reducing photogenerated charge recombination centers; providing trapping sites to promote charge separation; improving the stability of the overall system; providing more active sites; and offering a lower overpotential. The BiVO4/CoNiO2 photoanode has a higher photocurrent density (1.16 mA cm-2 at 1.23 V vs. RHE), a lower onset potential (â¼0.06 V vs. RHE), a larger IPCE (34.37%) and ABPE (0.163%), better stability and good rates of hydrogen evolution (0.0148 µmol cm-2 min-1) and oxygen evolution (0.0076 µmol cm-2 min-1). The strategy provides promising prospects for achieving efficient PEC water splitting performance using water oxidation cocatalysts.
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The self-assembly process of metal nanoparticles has aroused wide attention due to its low cost and simplicity. However, most of the recently reported self-assembly systems only involve two or fewer metals. Herein, we first report a successful synthesis of self-assembled Ag@AuCu trimetal nanoplates in aqueous solution. The building blocks of multibranched AuCu alloy nanocrystals were first synthesized by a chemical reduction method. The growth of Ag onto the AuCu nanocrystals in the presence of hexadecyltrimethylammonium chloride (CTAC) induces a self-assembly process and formation of Ag@AuCu trimetal nanoplates. These nanoplates with an average side length of over 2 µm show a porous morphology and a very clear boundary with the branches of the as-prepared AuCu alloy nanocrystals extending out. The shape and density of the Ag@AuCu trimetal nanoplates can be controlled by changing the reaction time and the concentration of silver nitrate. The as-assembled Ag@AuCu nanoplates are expected to have the potential for wide-ranging applications in surface-enhanced Raman scattering (SERS) and catalysis owing to their unique structures.
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PURPOSE OF THE REPORT: In vivo tau PET imaging could help clarify the spatial distribution of tau deposition in Alzheimer disease (AD) and aid in the differential diagnosis of tauopathies. To date, there have been no in vivo F-APN1607 tau PET studies in patients with AD. METHODS: We applied tau tracer in 12 normal controls (NCs) and 10 patients in the mild to moderate stage of probable AD. Detailed clinical information, cognitive measurements, and disease severity were documented. Regional SUV ratios (SUVRs) from F-AV-45 (florbetapir), F-APN1607 PET images, and regional gray matter (GM) atrophic ratios were calculated for further analysis. RESULTS: Quantitative analyses showed significantly elevated SUVRs in the frontal, temporal, parietal, occipital lobes, anterior and posterior cingulate gyri, precuneus, and parahippocampal region (all P's < 0.01) with medium to large effect sizes (0.44-0.75). The SUVRs from F-APN1607 PET imaging showed significant correlations with the Alzheimer's Disease Assessment Scale (ADAS-cog) scores (all P's < 0.01) and strong correlation coefficients (R ranged from 0.54 to 0.68), even adjusted for age and sex effects. Finally, the SUVRs from F-APN1607 PET imaging of the parahippocampal region showed rapid saturation as the ADAS-cog scores increased, and the SUVRs of the posterior cingulate gyrus and the temporal, frontal, parietal, and occipital regions slowly increased. The combined SUVRs from amyloid, tau PET, and regional GM atrophic ratio showed regional specific patterns as the ADAS-cog scores increased. CONCLUSIONS: Our findings suggest that the F-APN1607 tau tracer correlated well with cognitive changes and demonstrated the spatial pattern of amyloid, tau deposition, and GM atrophy in the progression of AD.
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Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Tomografía de Emisión de Positrones , Proteínas tau/metabolismo , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Background: Brain 18F-AV-45 amyloid positron emission tomography (PET) in Taiwanese patients with familial Alzheimer's disease with the amyloid precursor protein (APP) p.D678H mutation tends to involve occipital and cerebellar cortical areas. However, tau pathology in patients with this specific Taiwan mutation remains unknown. In this study, we aimed to study the Tau PET images in these patients. Methods: Clinical features, brain magnetic resonance imaging/computed tomography (MRI/CT), and brain 18F-THK-5351 PET were recorded in five patients with the APP p.D678H mutation and correlated with brain 18F-AV-45 PET images. We also compared the tau deposition patterns among five patients with familial mild cognitive impairment (fMCI), six patients with sporadic amnestic mild cognitive impairment (sMCI), nine patients with mild to moderate dementia due to Alzheimer's disease (AD), and 12 healthy controls (HCs). All of the subjects also received brain 18F-AV-45 PET. Results: The nine patients with sAD and six patients with sMCI had a positive brain AV-45 PET scans, while the 12 HCs had negative brain AV-45 PET scans. All five patients with fMCI received a tau PET scan with the age at onset ranging from 46 to 53 years, in whom increased standard uptake value ratio (SUVR) of 18F-THK-5351 was noted in all seven brain cortical areas compared with the HCs. In addition, the SUVRs of 18F-THK-5351 were increased in the frontal, medial parietal, lateral parietal, lateral temporal, and occipital areas (P < 0.001) in the patients with sAD compared with the HCs. The patients with fMCI had a significant higher SUVR of 18F-THK-5351 in the cerebellar cortex compared to the patients with sMCI. The correlations between regional SUVR and Mini-Mental State Examination score and between regional SUVR and clinical dementia rating (sum box) scores within volumes of interest of Braak stage were statistically significant. Conclusion: Tau deposition was increased in the patients with fMCI compared to the HCs. Increased regional SUVR in the cerebellar cortical area was a characteristic finding in the patients with fMCI. As compared between amyloid and tau PET, the amyloid deposition is diffuse, but tau deposition is limited to the temporal lobe in the patients with fMCI.
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INTRODUCTION: The novel D678H amyloid precursor protein (APP) gene mutation has been called the "Taiwan mutation". The study aims to identify amyloid deposition patterns and clinical features associated with this mutation. METHODS: we analyzed the clinical manifestations, brain neuroimages and 18F-AV-45 positron emission tomography (PET) findings in symptomatic patients and asymptomatic subjects with the autosomal-dominant Alzheimer's disease (AD). We compared the amyloid deposition pattern among 10 patients with genetically-positive familial cognitive decline (CD), 18 patients with sporadic CD, and 19 healthy controls. RESULTS: The clinical features were the early onset of memory impairment in all 10 patients and cerebral amyloid angiopathy in 3 patients. The characteristic results of brain 18F-AV-45 PET included the highest standard uptake value ratio (SUVR) in the occipital and cerebellar cortical areas in the genetically-positive CD patients. In subgroup analysis, the familial AD patients had a decreased amyloid SUVR trend in most areas except for cerebellar cortex compared to those with familial mild cognitive impairment. CONCLUSION: Our data indicate that the familial D678H gene mutation have resulted in a more potent amyloid burden than in the patients with sporadic AD patients. The high amyloid uptake in the occipital area is characteristic of the specific Taiwan APP gene.
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Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Angiopatía Amiloide Cerebral/genética , Mutación/genética , Tomografía de Emisión de Positrones/métodos , Adulto , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Angiopatía Amiloide Cerebral/diagnóstico por imagen , Angiopatía Amiloide Cerebral/metabolismo , Demencia/diagnóstico por imagen , Demencia/genética , Demencia/metabolismo , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Linaje , Taiwán/epidemiología , Adulto JovenRESUMEN
BACKGROUND: The amyloid AV-45 (florbetapir) positron emission tomography (PET) has been used in the study of the familial Alzheimer's disease (FAD) with the D678H amyloid precursor protein (APP) mutation. In addition, the progress of the disease remains unknown. OBJECTIVE: We aim to investigate the progression rate of amyloid accumulation in FAD patients with this mutation by neuroimages analysis. METHODS: The clinical course, changes in cognitive function, brain magnetic resonance imaging (MRI) and 18F-AV-45 PET scan were investigated in FAD patients and sporadic AD (sAD) patients. We compared the amyloid deposition pattern in serial brain 18F-AV-45 PET scan among the FAD, familial mild cognitive impairment (FMCI), and sMCI and sAD patients. RESULTS: Seven familial patients received a follow-up survey. The follow up duration for brain AV-45 PET was from 1.54 to 3.61 years. In 4 FMCI patients, an increased regional SUVR was noted, and the annual change rates were increased from 1.03% to 18.82%. However, a decreased regional SUVR was noted in 3 FAD patients and the annual change rates were from -2.62% to -16.03%. As compared with the sAD and sMCI patients, the annual change rate is statistically significant in FAD and FMCI patients respectively. CONCLUSIONS: The data indicate a biphasic course with an initial increase and then a decrease of SUVR in brain amyloid PET scan in familial APP mutation patients. The data also reveal that the novel Taiwan APP (D678H) mutation has a more amyloid burden than the sAD patients, particularly in an MCI stage.
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Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Encéfalo/metabolismo , Disfunción Cognitiva/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Compuestos de Anilina/farmacocinética , Ácido Aspártico/genética , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Progresión de la Enfermedad , Glicoles de Etileno/farmacocinética , Salud de la Familia , Femenino , Estudios de Seguimiento , Histidina/genética , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , TaiwánRESUMEN
The photoelectrochemical properties of g-C3N4 sheet are modified by the π-π stacking interaction with graphene, and the corresponding role of graphene on the surface chemical reactions is investigated by density functional theory. The calculated cohesive energies and the lattice mismatch energies indicate that g-C3N4 and graphene are in parallel contact and can form a stable heterojunction. According to our calculated energy band structures and work functions of g-C3N4/graphene heterojunctions, the band edge modulations by graphene are discussed and corresponding photoinduced charge transfer processes are analyzed in detail. It is found that the incorporating of graphene into g-C3N4 facilitates the separation of photoinduced e-/h+ pairs and the oxidation capacity enhancement of the photoinduced holes with the downshifting of the valence band edge of g-C3N4 layer. It is identified that the inhomogeneous onsite energies between interlayer and the band edge modulations are induced by the inhomogeneous charge redistribution between interlayer caused by graphene. Further, the initial dynamic reaction processes of oxygen atoms in g-C3N4/graphene heterojunctions also confirm the significant role of graphene on the surface chemical reactions.