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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.
Marco Bocchetti Maria Grazia Ferraro Filippo Ricciardiello Alessandro Ottaiano Amalia Luce Alessia Maria Cossu Marianna Scrima Wing-Yan Leung Marianna Abate Paola Stiuso Michele Caraglia Silvia Zappavigna Tung On Yau 《International journal of molecular sciences》2021,22(8)
Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18–25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes’ expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment. 相似文献
3.
Pengfei Wang Alson Kwun Leung Ng Alastair Dowler Heike Ebendorff-Heidepriem 《Journal of the American Ceramic Society》2021,104(2):833-850
For lead-germanate glass fibers, reducing the content of hydroxyl (OH) groups and the formation of metallic Pb species is essential to pave the way for their applications as low-loss mid-IR fiber optics since OH and metallic Pb species cause intense absorption and scattering loss, respectively, in the mid-IR spectral range. The first part of this study reported the optimization of the glass melting procedure to obtain low amount of OH while preventing formation of metallic Pb species in lead-germanate glass. Here, the second part of this study reports the investigation of the process conditions to fabricate low-loss lead-germanate glass fiber through further understanding of the co-effects of glass melting and heat treatment atmospheres on the formation of nano- and micron-scale metallic Pb species in both the as-produced and heat treated lead-germanate glasses. Finally, using this advance in knowledge, we successfully fabricated low-loss lead-germanate glass fibers with no presence of reduced metallic Pb particles by optimizing dehydration agent, glass melting, preform extrusion and fiber drawing conditions. The optimized fabrication conditions reduced the unstructured fiber loss by almost one order to <0.3 dB/m at 1.55 μm. 相似文献
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Currently, there is little information pertaining to the airborne bacterial communities of green buildings. In this case study, the air bacterial community of a zero carbon building (ZCB) in Hong Kong was characterized by targeting the bacterial 16S rRNA gene. Bacteria associated with the outdoor environment dominated the indoor airborne bacterial assemblage, with a modest contribution from bacteria associated with human skin. Differences in overall community diversity, membership, and composition associated with short (day‐to‐day) and long‐term temporal properties were detected, which may have been driven by specific environmental genera and taxa. Furthermore, time‐decay relationships in community membership (based on unweighted UniFrac distances) and composition (based on weighted UniFrac distances) differed depending on the season and sampling location. A Bayesian source‐tracking approach further supported the importance of adjacent outdoor air bacterial assemblage in sourcing the ZCB indoor bioaerosol. Despite the unique building attributes, the ZCB microbial assemblage detected and its temporal characteristics were not dissimilar to that of conventional built environments investigated previously. Future controlled experiments and microbial assemblage investigations of other ZCBs will undoubtedly uncover additional knowledge related to how airborne bacteria in green buildings may be influenced by their distinctive architectural attributes. 相似文献
6.
Smart cities are built upon information and communication technologies (ICTs) to enable a broad range of advanced services. Through a comprehensive literature review, this study identified four pitfalls brought by the pervasive application of ICT, including information insecurity, privacy leakage, information islands, and digital divide. Therefore, a questionnaire survey together with 27 interviews was conducted in Hong Kong to investigate how the public perceived these pitfalls within the context of mobile apps providing real-time parking information which form a major part of smart mobility. System insecurity and privacy leakage were found to arouse worries among the app-users while their awareness of protecting personal data was found to have room for improvement. Islands of real-time parking information occur as a result of the lack of collaboration among private carpark operators. Digital divide existed widely among the disadvantaged groups and the problem cannot be solved by mere provision of ICT facilities. Overall, technologies alone cannot make a city smart or smarter. It is the suitable way in which ICTs are used to serve all citizens that matters. 相似文献
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Kelly Yujie Wang Yuan Wen Tsz Leung Yip Meifeng Luo 《International Transactions in Operational Research》2020,27(5):2658-2682
As nonrecourse project finance (rather than financing on a sovereign basis) is becoming more prevalent worldwide, financing institutions have to collaborate more closely with firms to optimize capacity‐investment and financing decisions. Under this background, this paper presents a stylized Stackelberg games model, taking into account the firm's capacity investment as well as the bank's interest rate and funding ratio decisions. Consortium structures between bank and firm are formalized into five modes based on industry practice, namely, the integrated consortium, pure shareholder funding, bank as leader, full coordination, and bank as follower. The optimality and equilibrium of each of the five modes are analytically derived, and their existence and uniqueness are demonstrated. Valuable economic insights are obtained through both modeling analysis and numerical experiments, with the main findings including the following: (i) a lack of bank financing leads to insufficient capacity investment and poor consortium performance; (ii) interest rate and funding ratio play important but different roles in the bank's risk management; (iii) the bank's proactivity in leading and coordinating the consortium is critical for the two parties’ overall performance; and (iv) if the bank is the follower, the firm's capacity decision is irrelevant to the bank's loan contract, and the consortium cannot be coordinated to the first‐best level of performance. 相似文献
10.
Yeuk T. Lau Ka M. Ng Na Chen David T. W. Lau Kam M. Ko Ping C. Leung Christianto Wibowo 《American Institute of Chemical Engineers》2014,60(12):4014-4026
A quality assurance (QA) procedure for multiple‐herb extraction, which takes into account the existence of common chemical markers and multiple‐herb‐extraction effects, has been developed for producing Chinese herbal medicines (CHMs) of consistent quality. The experimental method for determining related correlation function of the multiple‐herb‐extraction effect was designed. A systematic solution strategy was also developed to appropriately decompose the multiple‐herb extraction system into several subsystems for obtaining solution(s) and determining the overall behavior of the system. An example of QA of Danshen–Gegen (DG) decoction was used to demonstrate the QA procedure. An H9c2 cell assay was used to test the efficacy of consistent quality DG decoctions prepared by different herb combinations with different material costs of herbs. It was observed that a multiple‐herb‐extraction effect was present in the aqueous extraction of Danshensu and this effect was depended on the extraction solvent. The possible mechanism of this multiple‐herb‐extraction effect in the aqueous DG extraction was speculated to be the change of initial pH value of the aqueous extraction solvent by an unknown component from Gegen. The experimental chemical marker concentrations fell within ±10% of the specified chemical marker compositions by using the amount of herb from each herb class as predicted by the QA model. Furthermore, an H9c2 cell assay was used to test the efficacy of three consistent quality DG extracts, which were produced by different herb combinations with different material costs of herbs. The results showed that the three DG extracts provided consistent biological efficacy against menadione‐induced toxicity. This study extended a recently developed QA procedure of single‐herb extraction to multiple‐herb extraction. It provides a solution of QA in extraction, which is one of the most important unresolved problems in the modernization of traditional Chinese medicines. With this modified model and the companion experiments, the amount of herbs needed from different quality classes to produce a multiple‐herb formula CHM product decoction with consistent quality can be exactly determined. © 2014 American Institute of Chemical Engineers AIChE J 60: 4014–4026, 2014 相似文献