Abstract
The Taiwanese people are composed of diverse indigenous populations and the Taiwanese Han. About 95% of the Taiwanese identify themselves as Taiwanese Han, but this may not be a homogeneous ...population because they migrated to the island from various regions of continental East Asia over a period of 400 years. Little is known about the underlying patterns of genetic ancestry, population admixture, and evolutionary adaptation in the Taiwanese Han people. Here, we analyzed the whole-genome single-nucleotide polymorphism genotyping data from 14,401 individuals of Taiwanese Han collected by the Taiwan Biobank and the whole-genome sequencing data for a subset of 772 people. We detected four major genetic ancestries with distinct geographic distributions (i.e., Northern, Southeastern, Japonic, and Island Southeast Asian ancestries) and signatures of population mixture contributing to the genomes of Taiwanese Han. We further scanned for signatures of positive natural selection that caused unusually long-range haplotypes and elevations of hitchhiked variants. As a result, we identified 16 candidate loci in which selection signals can be unambiguously localized at five single genes: CTNNA2, LRP1B, CSNK1G3, ASTN2, and NEO1. Statistical associations were examined in 16 metabolic-related traits to further elucidate the functional effects of each candidate gene. All five genes appear to have pleiotropic connections to various types of disease susceptibility and significant associations with at least one metabolic-related trait. Together, our results provide critical insights for understanding the evolutionary history and adaption of the Taiwanese Han population.
The micro-arc oxidation process was used to apply a ceramic oxide coating on a pure titanium substrate using calcium acetate and sodium dihydrogen phosphate as an electrolyte. The influence of the ...current frequency and duty ratio on the surface morphology, phase composition, wear behavior, and corrosion resistance were analyzed by employing a scanning electron microscope, X-ray diffractometer, ball-on-disk apparatus, and potentiodynamic polarization, respectively. Analyses of the surface and cross-sectional morphologies revealed that the MAO films prepared via a low current frequency (100 Hz) and a high duty ratio (60%) had a lower porosity and were more compact. The medium (500 Hz) and high (1000 Hz) frequencies at the higher duty ratios presented with better wear resistance. The highest film thickness (11.25 µm) was achieved at 100 Hz and a 20% duty ratio. A negligible current density was observed when the frequency was fixed at 500 Hz and 1000 Hz and the duty cycle was 20%.
Intelligent drug-delivery systems are considered one of the most important techniques for improving cancer treatment using existing over-the-counter medicines. However, metallic materials are always ...accompanied by metabolism problems, whereas chemotherapy produces several side effects in humans. Carbon-based materials exhibit exceptional features such as bio-affinity and bio-degradability. Herein, hollow mesoporous carbon nanoparticles (HMCs) are reported as effective nanocarriers of anti-cancer small drug molecules. Near IR (NIR) sources, which can penetrate most organs, induce thermal effects via non-invasive pathways. NIR radiation not only provides thermal therapy but also is compatible with temperature-sensitive coated responsive polymer shells. The template method was used to synthesize HMCs with size 200 ± 50 nm, under various conditions, to obtain suitably sized and hollow structures for liver-cancer treatment. Additional pH/thermal-bi-responsive poly(N-isopropylacrylamide) (PNIPAM) shells were further coated onto the HMCs to produce multiple shells that could trigger swelling motions in PNIPAM@HMCs, as confirmed via small-angle X-ray scattering (SAXS). NIR results demonstrated an extreme increase to the ∆T of 8.7 and 14.2 °C for HMC and PNIPAM@HMCs, respectively. The SAXS spectra analyzed using SasView simulations demonstrated the multi-shell structures of synthesized HMCs and the release mechanism of PNIPAM@HMCs. Based on the model simulation of SAXS, the different rates of polymer swelling indicated the core shrinkage (229.7 to 134.2 Å) and shell expansion (324.3 to 514.3 Å) at 37 °C and 42 °C, respectively. In addition, the first-order, Higuchi, Korsmeyer-Peppas, and Weibull mathematical models were used to verify the drug-release kinetics, and the model with the highest R
value was considered most suitable for further application. This paper presents the first SAXS study on PNIPAM@HMCs release kinetics and related mechanisms. This phenomenon indicates NIR-induced PNIPAM@HMCs as an effective strategy for cancer treatment via doxorubicin release.
Abstract
Insular flying foxes are keystone species in island ecosystems due to their critical roles in plant pollination and seed dispersal. These species are vulnerable to population decline because ...of their small populations and low reproductive rates. The Formosan flying fox (Pteropus dasymallus formosus) is one of the 5 subspecies of the Ryukyu flying fox. Pteropus dasymallus formosus has suffered from a severe decline and is currently recognized as a critically endangered population in Taiwan. On the contrary, the Orii’s flying fox (Pteropus dasymallus inopinatus) is a relatively stable population inhabiting Okinawa Island. Here, we applied a genomic approach called double digest restriction-site associated DNA sequencing to study these 2 subspecies for a total of 7 individuals. We detected significant genetic structure between the 2 populations. Despite their contrasting contemporary population sizes, both populations harbor very low degrees of genetic diversity. We further inferred their demographic history based on the joint folded site frequency spectrum and revealed that both P. d. formosus and P. d. inopinatus had maintained small population sizes for a long period of time after their divergence. Recently, these populations experienced distinct trajectories of demographic changes. While P. d. formosus suffered from a drastic ~10-fold population decline not long ago, P. d. inopinatus underwent a ~4.5-fold population expansion. Our results suggest separate conservation management for the 2 populations—population recovery is urgently needed for P. d. formosus while long-term monitoring for adverse genetic effects should be considered for P. d. inopinatus.
To compare the neocortical amyloid loads among cognitively normal (CN), amnestic mild cognitive impairment (aMCI), and Alzheimer's disease (AD) subjects with (18)FAV-45 positron emission tomography ...(PET).
(18)FAV-45 PET was performed in 11 CN, 13 aMCI, and 12 AD subjects to compare the cerebral cortex-to-whole cerebellum standard uptake value ratios (SUVRs) of global and individual volumes of interest (VOIs) cerebral cortex. The correlation between global cortical (18)FAV-45 SUVRs and Mini-Mental State Examination (MMSE) scores was analyzed.
The global cortical (18)FAV-45 SUVRs were significantly different among the CN (1.08±0.08), aMCI (1.27±0.06), and AD groups (1.34±0.13) (p = 0.0003) with amyloidosis positivity rates of 9%, 62%, and 92% in the three groups respectively. Compared to CN subjects, AD subjects had higher SUVRs in the global cortical, precuneus, frontal, parietal, occipital, temporal, and posterior cingulate areas; while aMCI subjects had higher values in the global cortical, precuneus, frontal, occipital and posterior cingulate areas. There were negative correlations of MMSE scores with SUVRs in the global cortical, precuneus, frontal, parietal, occipital, temporal, posterior cingulate and anterior cingulate areas on a combined subject pool of the three groups after age and education attainment adjustment.
Amyloid deposition occurs relatively early in precuneus, frontal and posterior cingulate in aMCI subjects. Higher (18)FAV-45 accumulation is present in parietal, occipital and temporal gyri in AD subjects compared to the aMCI group. Significant correlation between MMSE scores and (18)FAV-45 SUVRs can be observed among CN, aMCI and AD subjects.
A core–shell gelatin–alginate composite used for intestine‐released oral delivery drug carrier was synthesized through microfluidic technique. At the fixed continuous phase flow rate, the size of the ...core–shell gelatin–alginate microparticles increases with the dispersed phase flow rate, and monodispersity can be retained (the variation coefficient for the diameter distribution can be kept less than 10%). The fabricated microparticles could remain intact in gastric juice for at least 3 h, indicating that the gelatin core could be well protected by alginate shell in acid environment. However, the alginate shell of the microparticles would swell or collapse in alkali environment in half an hour, assuring the controlled drug release in intestinal juice. The fabricated uniform core–shell gelatin–alginate microparticles were potential as pH‐responsive drug carriers.
Objective
Lactacystin has been used to establish rodent models of Parkinson disease (PD), with cerebral α-synuclein inclusions. This study evaluated the uptake of
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...F9-fluoropropyl-(+)-dihydrotetrabenazine (
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FFP-(+)-DTBZ), a vesicular monoamine transporter type 2 (VMAT2)-targeting radiotracer, through positron emission tomography (PET) in lactacystin-treated rat brains.
Methods
Adult male Sprague–Dawley rats were randomly treated with a single intracranial dose of lactacystin (2 or 5 μg) or saline (served as the sham control) into the left medial forebrain bundle. A 30-min static
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FFP-(+)-DTBZ brain PET scan was performed following an intravenous
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FFP-(+)-DTBZ dose (approximately 22 MBq) in each animal at 2 and 3 weeks after lactacystin treatment. Upon completing the last PET scans, the animals were killed, and their brains were dissected for ex vivo autoradiography (ARG) and immunohistochemical (IHC) staining of tyrosine hydroxylase (TH) as well as VMAT2.
Results
Both the 2- and 5-μg lactacystin-treated groups exhibited significantly decreased specific
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FFP-(+)-DTBZ uptake in the ipsilateral striata (I-ST) at 2 weeks (1.51 and 1.16, respectively) and 3 weeks (1.36 and 1.00, respectively) after lactacystin treatment, compared with the uptake in the corresponding contralateral striata (C-ST) (3.48 and 3.08 for the 2- and 5-μg lactacystin-treated groups, respectively, at 2 weeks; 3.36 and 3.11 for the 2- and 5-μg lactacystin-treated groups, respectively, at 3 weeks) and the sham controls (3.34–3.53). Lactacystin-induced decline in I-ST
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FFP-(+)-DTBZ uptake was also demonstrated through ex vivo ARG, and the corresponding dopaminergic neuron damage was confirmed by the results of TH- and VMAT2-IHC studies.
Conclusions
In this PD model, lactacystin-induced dopaminergic terminal damage in the ipsilateral striatum could be clearly visualized through in vivo
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FFP-(+)-DTBZ PET imaging. This may serve as a useful approach for evaluating the effectiveness of new treatments for PD.
Currently, diagnosis of Parkinson disease is mainly based on clinical criteria characterized by motor symptoms including bradykinesia, rigidity, resting tremor, and postural instability. Reliable in ...vivo biomarkers to monitor disease severity and reflect the underlying dopaminergic degeneration are important for future disease-modifying therapy in Parkinson disease.
To use 18F9-fluoropropyl-(+)-dihydrotetrabenazine (18F-DTBZ; 18FAV-133) positron emission tomography (PET) to explore the characteristics of vesicular monoamine transporter type 2 imaging in patients with Parkinson disease (PD) with different severity levels as well as to investigate its capability in monitoring clinical severity.
Regional uptakes for 18F-DTBZ PET of different disease stages were measured. Seventeen healthy control participants and 53 patients in 3 groups of mild, moderate, and advanced stages of PD were recruited for 18F-DTBZ PET scans from the Movement Disorders Clinic in the Chang Gung Memorial Hospital, Taiwan.
The severity of disease in patients with PD was quantified by modified Hoehn-Yahr Scale, Unified Parkinson Disease Rating Scale total scores and subscores of posture instability and gait disturbance, tremor, akinesia, and rigidity while not taking medication. Both voxelwise- and volume of interest-based image analyses were performed. The specific uptake ratio (SUR) of each volume of interest and voxel was calculated as (target uptake - reference uptake) / reference uptake using the occipital reference region from magnetic resonance imaging-based spatially normalized 18F-DTBZ images for each participant. Average SUR images were displayed as 2-dimensional and 3-dimensional to illustrate the image patterns in each group. The nonparametric Kruskal-Wallis test on regional SUR was used for group comparison between healthy control participants and patients with PD at different stages. Quantitative parameters were correlated with severity of disease and disease duration by Spearman correlation. Voxelwise analysis for evaluating dopaminergic neuron decline of different PD stages was performed by SPM5.
The 2-dimensional and 3-dimensional 18F-DTBZ PET images demonstrated that the reduction of vesicular monoamine transporter type 2 availability was obviously correlated with the severity of disease in patients with PD. The mean reductions of vesicular monoamine transporter type 2 density for the caudate, putamen,and substantia nigra were 21.50%, 58.20%, and 21.10% for mild PDParkinson disease;60.75%, 79.49%,and 39.87%formoderate PD; and63.94%,83.20%, and 44.00% for advanced PD, respectively corrected. The SURs of bilateral striatal regions exhibited significantly exponential correlations to stage; disease duration; Unified Parkinson Disease Rating Scale motor score; posture instability and gait disturbance; and akinesia, rigidity, and tremor scores.
In PD, 18F-DTBZ PET is a potential imaging biomarker for measuring dopaminergic degeneration in vivo and monitoring the severity of disease.
PET with (18)F-9-fluoropropyl-(+)-dihydrotetrabenzazine ((18)F-DTBZ), a novel radiotracer targeting vesicular monoamine transporter type 2 (VMAT2), has been proven as a useful imaging marker to ...measure dopaminergic integrity.
The aim of this study was to evaluate the capability of (18)F-DTBZ PET in detecting the monoaminergic degeneration in early Parkinson disease (PD) in vivo. Seventeen age-matched healthy subjects and 30 PD patients at early stage of disease (duration of disease ≤ 5 y) with mild and unilateral motor symptoms underwent (18)F-DTBZ PET scans. The severity of disease, including Unified Parkinson Disease Rating Scale and modified Hoehn and Yahr Stage (mHY), were recorded at off-medication states. The standardized volumes of interest were applied to the spatial normalized image for quantification analysis. The specific uptake ratios (SURs) were calculated according to the formula (specific volumes-of-interest counts/occipital cortex counts) - 1. SUR measurements were summarized for each brain region.
The mean duration of disease in the PD group was 3.2 ± 2.1 y (range, 0.5-5 y). The mean mHY was 1.0 ± 0.1 (range, 1-1.5). The SURs of bilateral caudate, anterior putamen, posterior putamen, substantia nigra, and nucleus accumbens were significantly lower in PD patients than those of healthy subjects. The reduction of SURs was most severe in the contralateral (the brain regions that are located opposite to the symptomatic side) posterior putamen (-81%), followed by the ipsilateral posterior putamen (-67%). Receiver-operating-characteristic curve analysis showed that the SURs of the bilateral posterior putamen and contralateral anterior putamen had a sensitivity of 100% and specificity of 100% in differentiating PD patients from healthy subjects.
(18)F-DTBZ PET was as an excellent tool for the early diagnosis of PD. The obvious decline of (18)F-DTBZ uptake in the ipsilateral (asymptomatic) striatum suggested that (18)F-DTBZ PET might serve as an in vivo biomarker to detect the monoaminergic degeneration in the premotor phase of PD.