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1.
Ava Kwong Cecilia Y. S. Ho Vivian Y. Shin Chun Hang Au Tsun Leung Chan Edmond S. K. Ma 《International journal of molecular sciences》2021,22(2)
The germline carrier of the BRCA1 pathogenic mutation has been well proven to confer an increased risk of breast and ovarian cancer. Despite BRCA1 biallelic pathogenic mutations being extremely rare, they have been reported to be embryonically lethal or to cause Fanconi anemia (FA). Here we describe a patient who was a 48-year-old female identified with biallelic pathogenic mutations of the BRCA1 gene, with no or very subtle FA-features. She was diagnosed with ovarian cancer and breast cancer at the ages of 43 and 44 and had a strong family history of breast and gynecological cancers. 相似文献
2.
Shraddha Parate Vikas Kumar Danishuddin Jong Chan Hong Keun Woo Lee 《International journal of molecular sciences》2021,22(10)
Heparanase (Hpse) is an endo-β-D-glucuronidase capable of cleaving heparan sulfate side chains. Its upregulated expression is implicated in tumor growth, metastasis and angiogenesis, thus making it an attractive target in cancer therapeutics. Currently, a few small molecule inhibitors have been reported to inhibit Hpse, with promising oral administration and pharmacokinetic (PK) properties. In the present study, a ligand-based pharmacophore model was generated from a dataset of well-known active small molecule Hpse inhibitors which were observed to display favorable PK properties. The compounds from the InterBioScreen database of natural (69,034) and synthetic (195,469) molecules were first filtered for their drug-likeness and the pharmacophore model was used to screen the drug-like database. The compounds acquired from screening were subjected to molecular docking with Heparanase, where two molecules used in pharmacophore generation were used as reference. From the docking analysis, 33 compounds displayed higher docking scores than the reference and favorable interactions with the catalytic residues. Complex interactions were further evaluated by molecular dynamics simulations to assess their stability over a period of 50 ns. Furthermore, the binding free energies of the 33 compounds revealed 2 natural and 2 synthetic compounds, with better binding affinities than reference molecules, and were, therefore, deemed as hits. The hit compounds presented from this in silico investigation could act as potent Heparanase inhibitors and further serve as lead scaffolds to develop compounds targeting Heparanase upregulation in cancer. 相似文献
3.
Yoga Sugama Salim Norsyazlin Abd Rashid Suhaila Idayu Abdul Halim Chin Han Chan Chong Hup Ong Mohamad Kamal Harun 《Polymer Engineering and Science》2021,61(11):2757-2770
Standardization of Fourier transform infrared (FTIR) fingerprint region for paints and assessment on the reproducibility using different spectrophotometers were investigated. While selective fingerprint regions may be confusing for technicians/analysts who are non-chemists, we attempt to generalize these regions (e.g., 1300–1000 cm−1 for Epoxy part A and 1400–1000 cm−1 for Epoxy part B) by choosing a universal region (2000–900 cm−1) that works for different paints. Comparison result using a paired student t-test shows that the degree of similarity (r) values from the studied regions are not statistically different. The paint fails the screening analysis occasionally on-site when analyzed using handheld FTIR due to the higher level of noise that gives low r values (r < 0.900 ± 0.002). The same samples were analyzed using a benchtop FTIR and the r values are above 0.900 ± 0.002. While the screening may lead to a false rejection of the sample on-site, there could be occurrence of false acceptance. The on-site screening of EPZ part A with different formulations, for instance, shows that the r values over the entire IR spectrum are above 0.900 ± 0.002 when analyzed using handheld FTIR. After the samples were analyzed using the benchtop, the r values fall below 0.900 ± 0.002. 相似文献
4.
Phuong-Anh Ngoc Doan Tzyi-Horng Tan Lee Fong Siow Beng Ti Tey Eng Seng Chan Teck-Kim Tang Nur Azwani Abdul Karim Eng-Tong Phuah Yee-Ying Lee 《Journal of the American Oil Chemists' Society》2021,98(6):609-620
Palm fatty acid distillate (PFAD) is a rich source of vitamin E. As compared to other vegetable oil, PFAD has higher tocotrienol (70–80%) over tocopherol content, which makes it a valuable source for vitamin E extraction. Current vitamin E extraction methods are not sustainable due to the intensive usage of chemical and high operational cost. Hence, the present study investigated for the first time using dry fractionation process as a green and economical pretreatment method for separating solid fraction (stearin) and liquid fraction (olein) in order to concentrate vitamin E from PFAD in olein fraction. We examined the dry fractionation conditions: crystallization ending temperature (36–44 °C), cooling rate (0.3 and 1.5°C min−1), stirring speed (20–125 rpm), and holding time (0–60 min) on the composition of unsaturated and saturated fatty acids as well as vitamin E content in liquid fraction (olein) and solid fraction (stearin) using gas chromatography and high performance liquid chromatography, respectively. In most of these conditions, vitamin E was ultimately higher in olein fraction as compared to stearin fraction, which is correlated with the high degree of unsaturation. Under a cooling rate of 0.3°C min−1, 90 rpm stirring speed, and ending crystallization of 38 °C, the highest vitamin E rich olein fraction was attained with 1479 ± 10.51 ppm in 50 g olein fraction as compared to 1366 ± 7.94 ppm in 500 g of unfractionated PFAD. 相似文献
5.
Yonghyun Kim Huiwen Liu Yi Liu Boa Jin Hao Zhang Wenjing Tian Chan Im 《Frontiers of Chemical Science and Engineering》2021,15(1):187-197
Cesium lead halide perovskite(CsPbX3,X=Cl,Br,I)quantum dots(QDs)and their partly Mn2+-substituted QDs(CsPb1–xMnxX3)attract considerable attention owing to their unique photoluminescence(PL)efficiencies.The two types of QDs,having different PL decay dynamics,needed to be further investigated in a form of aggregates to understand their solid-state-induced exciton dynamics in conjunction with their behaviors upon degradation to achieve practical applications of those promising QDs.However,thus far,these QDs have not been sufficiently investigated to obtain deep insights related to the long-term stability of their PL properties as aggregated solid-states.Therefore,in this study,we comparatively examined CsPbX3-and CsPb1–xMnxX3-type QDs stocked for>50 d under dark ambient conditions by using excitation wavelength-dependent PL quantum yield and time-resolved PL spectroscopy.These investigations were performed with powder samples in addition to solutions to determine the influence of the inter-QD interaction of the aged QD aggregates on their radiative decays.It turns out that the Mn2+-substituted QDs exhibited long-lasting PL quantum efficiencies,while the unsubstituted CsPbX3-type QDs exhibited a drastic reduction of their PL efficiencies.And the obtained PL traces were clearly sensitive to the sample status.This is discussed with the possible interaction depending on the size and distance of the QD aggregates. 相似文献
6.
随着物联网(Internet of Things,IoT)技术的快速发展,出现了大量具有不同功能的设备(如多种带不同传感器的智能家居设备、移动智能交通设备、智能物流或仓储管理设备等),它们相互连接,被广泛应用于智能城市、智慧工厂等领域。然而,这些物联网设备的处理能力有限,很难满足延迟敏感、计算密集型应用的需求。移动边缘计算(Mobile Edge Computing,MEC)的出现有效解决了这一问题。物联网设备可以将任务卸载到MEC服务器上,借助它们完成相应的计算任务。这些服务器通常由网络运营商部署在网络边缘,即靠近用户端的网络接入层,用于汇聚用户网络的网络层面。某一段时间内,物联网设备可能处于多个MEC服务器的覆盖区域中,多个设备共享服务器有限的计算和通信资源。在这个复杂环境下,制定一个任务卸载和资源分配方案,使得任务完成的时延或物联网设备的能耗达到最优化,是一个NP-难问题。目前,已有许多工作对这一问题进行了研究,并取得了一定的成果,但在实际的应用中仍面临着一些问题。为了更深入地推进该领域的研究,文中对近几年的最新研究成果进行了分析、归纳和总结,对比分析了它们的优缺点,并对未来的工作进行了展望。 相似文献
7.
Hui Huang Bradi R. Lorenz Paula Horn Zelmanovitz Catherine B. Chan 《International journal of molecular sciences》2021,22(1)
Prediabetes is a high-risk condition for type 2 diabetes (T2D). Pancreatic β-cells adapt to impaired glucose regulation in prediabetes by increasing insulin secretion and β-cell mass expansion. In people with prediabetes, metformin has been shown to prevent prediabetes conversion to diabetes. However, emerging evidence indicates that metformin has negative effects on β-cell function and survival. Our previous study established the Nile rat (NR) as a model for prediabetes, recapitulating characteristics of human β-cell compensation in function and mass expansion. In this study, we investigated the action of metformin on β-cells in vivo and in vitro. A 7-week metformin treatment improved glucose tolerance by reducing hepatic glucose output and enhancing insulin secretion. Although high-dose metformin inhibited β-cell glucose-stimulated insulin secretion in vitro, stimulation of β-cell insulin secretion was preserved in metformin-treated NRs via an indirect mechanism. Moreover, β-cells in NRs receiving metformin exhibited increased endoplasmic reticulum (ER) chaperones and alleviated apoptotic unfold protein response (UPR) without changes in the expression of cell identity genes. Additionally, metformin did not suppress β-cell mass compensation or proliferation. Taken together, despite the conflicting role indicated by in vitro studies, administration of metformin does not exert a negative effect on β-cell function or cell mass and, instead, early metformin treatment may help protect β-cells from exhaustion and decompensation. 相似文献
8.
A carbon-containing CoCrFeNi high entropy alloy (HEA) with heterogeneous structures was obtained through thermome-chanical treatments,which induced concurrent recrystallization and carbide precipitation in the alloy.A combination of high yield strength (556 MPa) and large uniform elongation (45%) was achieved in the investigated alloy.The enhancement of the strength is attributed to the combined effects of grain refinement,precipitation strengthening and microstructural het-erogeneity.Our work demonstrated that the heterogeneity design could be realized by thermomechanical processes,which provided a practical strategy for producing HEAs with high performance. 相似文献
9.
应用近红外光谱技术实现对小龙虾新鲜度的快速检测。利用化学计量学方法,通过对近红外品质分析仪采集的虾肉绞碎前后光谱(850~1 050 nm)调整不同预处理方法、偏最小二乘法和组合算法,建立一种基于总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量的小龙虾新鲜度定量预测模型。结果表明:采用标准正态变量变换与一阶导数结合的预处理方法模型预测效果最好,且绞碎后的虾肉光谱比绞碎前建模效果更好;为满足实际应用需要,对绞碎前的虾肉TVB-N含量预测模型进行分析,其交叉验证误差为3.123,交叉验证相关系数为0.947,用此模型对预测集24 个样品进行预测,预测值与实测值的交叉验证相关系数为0.951 4,在TVB-N含量超过20 mg/100 g(不新鲜)的检测准确率为100%。近红外光谱技术可应用于快速检测小龙虾新鲜度,所建模型具有较好的预测能力。 相似文献
10.
Chan Young Park 《建筑学研究前沿(英文版)》2022,11(4):747-760
This study identifies the types of areas in Seoul where foreigners are concentrated by reflecting the characteristics of their region of origin and residence in Seoul. Lack of cultural understanding and uniform policies for various immigrant communities are causing some social issues. Hence, this study aims to prepare the basic data from which the government can predict changes in ethnic areas and prepare policies suitable for each derived type. The 14 most populous immigrant communities in Seoul were investigated, and cluster analysis and ANOVA test were performed. This examination resulted in four immigrant community types. Each type has specific characteristics, which have influenced the creation and change of the built environment. Types 1 and 4 are collectivistic. These types gradually tend to change urban environments to emulate the environment in their region of origin. In addition, they make little effort to improve their degraded environments, and such areas become increasingly backward. In contrast, types 2 and 3 are individualistic and prefer to assimilate into a migrant region. The formation and change of the urban environment for each type can be predicted on the basis of these characteristics. From this information, the government can prepare an appropriate urban architecture policy for each type. 相似文献