| 1. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
- Chen, Yan-Ting, et al.
(författare)
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Biomimetic Platelet Nanomotors for Site-Specific Thrombolysis and Ischemic Injury Alleviation
- 2023
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 15:27, s. 32967-32983
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Tidskriftsartikel (refereegranskat)abstract
- Due to the mortality associated with thrombosis and its highrecurrence rate, there is a need to investigate antithrombotic approaches.Noninvasive site-specific thrombolysis is a current approach being used; however,its usage is characterized by the following limitations: low targeting efficiency, poorability to penetrate clots, rapid half-life, lack of vascular restoration mechanisms,and risk of thrombus recurrence that is comparable to that of traditionalpharmacological thrombolysis agents. Therefore, it is vital to develop an alternativetechnique that can overcome the aforementioned limitations. To this end, a cottonball-shaped platelet (PLT)-mimetic self-assembly framework engineered with aphototherapeutic poly(3,4-ethylenedioxythiophene) (PEDOT) platform has beendeveloped. This platform is capable of delivering a synthetic peptide derived fromhirudin P6 (P6) to thrombus lesions, forming P6@PEDOT@PLT nanomotors fornoninvasive site-specific thrombolysis, effective anticoagulation, and vascularrestoration. Regulated by P-selectin mediation, the P6@PEDOT@PLT nanomotors target the thrombus site and subsequentlyrupture under near-infrared (NIR) irradiation, achieving desirable sequential drug delivery. Furthermore, the movement ability ofthe P6@PEDOT@PLT nanomotors under NIR irradiation enables effective penetration deep into thrombus lesions, enhancingbioavailability. Biodistribution analyses have shown that the administered P6@PEDOT@PLT nanomotors exhibit extendedcirculation time and metabolic capabilities. In addition, the photothermal therapy/photoelectric therapy combination cansignificantly augment the effectiveness (ca. 72%) of thrombolysis. Consequently, the precisely delivered drug and the resultantphototherapeutic-driven heat-shock protein, immunomodulatory, anti-inflammatory, and inhibitory plasminogen activator inhibitor1 (PAI-1) activities can restore vessels and effectively prevent rethrombosis. The described biomimetic P6@PEDOT@PLTnanomotors represent a promising option for improving the efficacy of antithrombotic therapy in thrombus-related illnesses.
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| 3. |
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| 4. |
- Abbafati, Cristiana, et al.
(författare)
-
- 2020
-
Tidskriftsartikel (refereegranskat)
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| 5. |
- Axfors, Cathrine, et al.
(författare)
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Mortality outcomes with hydroxychloroquine and chloroquine in COVID-19 from an international collaborative meta-analysis of randomized trials
- 2021
-
Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Substantial COVID-19 research investment has been allocated to randomized clinical trials (RCTs) on hydroxychloroquine/chloroquine, which currently face recruitment challenges or early discontinuation. We aim to estimate the effects of hydroxychloroquine and chloroquine on survival in COVID-19 from all currently available RCT evidence, published and unpublished. We present a rapid meta-analysis of ongoing, completed, or discontinued RCTs on hydroxychloroquine or chloroquine treatment for any COVID-19 patients (protocol: https://osf.io/QESV4/). We systematically identified unpublished RCTs (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Cochrane COVID-registry up to June 11, 2020), and published RCTs (PubMed, medRxiv and bioRxiv up to October 16, 2020). All-cause mortality has been extracted (publications/preprints) or requested from investigators and combined in random-effects meta-analyses, calculating odds ratios (ORs) with 95% confidence intervals (CIs), separately for hydroxychloroquine and chloroquine. Prespecified subgroup analyses include patient setting, diagnostic confirmation, control type, and publication status. Sixty-three trials were potentially eligible. We included 14 unpublished trials (1308 patients) and 14 publications/preprints (9011 patients). Results for hydroxychloroquine are dominated by RECOVERY and WHO SOLIDARITY, two highly pragmatic trials, which employed relatively high doses and included 4716 and 1853 patients, respectively (67% of the total sample size). The combined OR on all-cause mortality for hydroxychloroquine is 1.11 (95% CI: 1.02, 1.20; I-2=0%; 26 trials; 10,012 patients) and for chloroquine 1.77 (95%CI: 0.15, 21.13, I-2=0%; 4 trials; 307 patients). We identified no subgroup effects. We found that treatment with hydroxychloroquine is associated with increased mortality in COVID-19 patients, and there is no benefit of chloroquine. Findings have unclear generalizability to outpatients, children, pregnant women, and people with comorbidities. Hydroxychloroquine and chloroquine have been investigated as a potential treatment for Covid-19 in several clinical trials. Here the authors report a meta-analysis of published and unpublished trials, and show that treatment with hydroxychloroquine for patients with Covid-19 was associated with increased mortality, and there was no benefit from chloroquine.
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| 6. |
- Cegelski, Lynette, et al.
(författare)
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Small-molecule inhibitors target Escherichia coli amyloid biogenesis and biofilm formation
- 2009
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Ingår i: Nature Chemical Biology. - : Nature Publishing Group. - 1552-4450 .- 1552-4469. ; 5:12, s. 913-919
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Tidskriftsartikel (refereegranskat)abstract
- Curli are functional extracellular amyloid fibers produced by uropathogenic Escherichia coli (UPEC) and other Enterobacteriaceae. Ring-fused 2-pyridones, such as FN075 and BibC6, inhibited curli biogenesis in UPEC and prevented the in vitro polymerization of the major curli subunit protein CsgA. The curlicides FN075 and BibC6 share a common chemical lineage with other ring-fused 2-pyridones termed pilicides. Pilicides inhibit the assembly of type1pili, which are required for pathogenesis during urinary tract infection. Notably, the curlicides retained pilicide activities and inhibited both curli-dependent and type 1–dependent biofilms. Furthermore, pretreatment of UPEC with FN075 significantly attenuated virulence in a mouse model of urinary tract infection. Curli and type 1pili exhibited exclusive and independent roles in promoting UPEC biofilms, and curli provided a fitness advantage in vivo. Thus, the ability of FN075 to block the biogenesis of both curli and type 1pili endows unique anti-biofilm and anti-virulence activities on these compounds.
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| 7. |
- Chen, Min-Wei, et al.
(författare)
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H3K9 histone methyltransferase G9a promotes lung cancer invasion and metastasis by silencing the cell adhesion molecule Ep-CAM
- 2010
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Ingår i: Cancer Research. - : American Association for Cancer Research. - 0008-5472 .- 1538-7445. ; 70:20, s. 7830-7840
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Tidskriftsartikel (refereegranskat)abstract
- G9a is a mammalian histone methyltransferase that contributes to the epigenetic silencing of tumor suppressor genes. Emerging evidence suggests that G9a is required to maintain the malignant phenotype, but the role of G9a function in mediating tumor metastasis has not been explored. Here, we show that G9a is expressed in aggressive lung cancer cells, and its elevated expression correlates with poor prognosis. RNAi-mediated knockdown of G9a in highly invasive lung cancer cells inhibited cell migration and invasion in vitro and metastasis in vivo. Conversely, ectopic G9a expression in weakly invasive lung cancer cells increased motility and metastasis. Mechanistic investigations suggested that repression of the cell adhesion molecule Ep-CAM mediated the effects of G9a. First, RNAi-mediated knockdown of Ep-CAM partially relieved metastasis suppression imposed by G9a suppression. Second, an inverse correlation between G9a and Ep-CAM expression existed in primary lung cancer. Third, Ep-CAM repression was associated with promoter methylation and an enrichment for dimethylated histone H3K9. G9a knockdown reduced the levels of H3K9 dimethylation and decreased the recruitment of the transcriptional cofactors HP1, DNMT1, and HDAC1 to the Ep-CAM promoter. Our findings establish a functional contribution of G9a overexpression with concomitant dysregulation of epigenetic pathways in lung cancer progression.
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| 8. |
- Chien, Ming-Hsien, et al.
(författare)
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Vascular endothelial growth factor-C (VEGF-C) promotes angiogenesis by induction of COX-2 in leukemic cells via the VEGF-R3/JNK/AP-1 pathway.
- 2009
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Ingår i: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 30:12, s. 2005-13
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Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factor (VEGF)-C is recognized as a tumor lymphangiogenic factor based on the effects of activated VEGF-R3 on lymphatic endothelial cells. Many tumor cells express VEGF-R3 but the function of this receptor in tumor cells is largely unknown. It has been reported that the VEGF-C/VEGF-R3 axis is activated in subsets of leukemia patients. Herein, we have shown that VEGF-C induces angiogenic activity in the tube formation assay invitro and Matrigel plug assay in vivo by upregulating an angiogenic factor, cyclooxygenase-2 (COX-2), through VEGF-R3 in the human acute myeloid leukemia (AML) cell line, THP-1. COX-2 induction by VEGF-C was also observed in other VEGF-R3(+) human AML cell lines (U937 and HL60). Moreover, immunohistochemical analysis of bone marrow specimens of 37 patients diagnosed with AML revealed that VEGF-C expression in specimens was associated with the expression of COX-2 (P < 0.001). The manner by which signaling pathways transduced by VEGF-C is responsible for COX-2 upregulation was further investigated. Blocking the p42/44 mitogen-activated protein kinase (MAPK) pathway with the MAPK kinase inhibitor, PD 98059, failed to inhibit VEGF-C-mediated COX-2 expression. However, VEGF-C-induced COX-2 upregulation was effectively abolished by overexpression of dominant-negative c-Jun N-terminal kinase (JNK) or treatment with the JNK inhibitor, SP 600125. VEGF-C induced JNK-dependent nuclear translocation of c-Jun. Furthermore, chromatin immunoprecipitation and reporter assays revealed that VEGF-C enhanced c-Jun binding to the cyclic adenosine 3',5'-monophosphate-response element of the COX-2 promoter and induced COX-2 expression. In sum, the data herein highlight the pathogenic role of VEGF-C in leukemia via regulation of angiogenesis through upregulation of COX-2.
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| 9. |
- Dumitrescu, Adrian, et al.
(författare)
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Finding Small Complete Subgraphs Efficiently
- 2023
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Ingår i: Combinatorial Algorithms - 34th International Workshop, IWOCA 2023, Proceedings. - 1611-3349 .- 0302-9743. - 9783031343469 ; 13889 LNCS, s. 185-196
-
Konferensbidrag (refereegranskat)abstract
- (I) We revisit the algorithmic problem of finding all triangles in a graph G= (V, E) with n vertices and m edges. According to a result of Chiba and Nishizeki (1985), this task can be achieved by a combinatorial algorithm running in O(mα) = O(m3 / 2) time, where α= α(G) is the graph arboricity. We provide a new very simple combinatorial algorithm for finding all triangles in a graph and show that is amenable to the same running time analysis. We derive these worst-case bounds from first principles and with very simple proofs that do not rely on classic results due to Nash-Williams from the 1960s. (II) We extend our arguments to the problem of finding all small complete subgraphs of a given fixed size. We show that the dependency on m and α in the running time O(αℓ-2· m) of the algorithm of Chiba and Nishizeki for listing all copies of Kℓ, where ℓ≥ 3, is asymptotically tight. (III) We give improved arboricity-sensitive running times for counting and/or detection of copies of Kℓ, for small ℓ≥ 4. A key ingredient in our algorithms is, once again, the algorithm of Chiba and Nishizeki. Our new algorithms are faster than all previous algorithms in certain high-range arboricity intervals for every ℓ≥ 7.
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| 10. |
- Hashemzehi, Mojgan, et al.
(författare)
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Modelling and optimization of main independent parameters for biodiesel production over a Cu0.4Zn0.6Al2O4 catalyst using an RSM method
- 2021
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Ingår i: Journal of chemical technology and biotechnology (1986). - : John Wiley & Sons. - 0268-2575 .- 1097-4660. ; 97:1, s. 111-119
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Tidskriftsartikel (refereegranskat)abstract
- In this research, the modeling of Cu0.4Zn0.6Al2O4 catalysts performance and optimizing of esterification reactions were considered by the central composite design (RSM) response method. The main independent parameters of temperature, the ratio of alcohol to oil, the amount of catalyst and time duration have been considered for setting the esterification process. To access the maximum activity in the esterification process, the optimum conditions are estimated at 10.42 the molar ratio of alcohol to oil, 2.98 wt.% for the amount of catalyst at the temperature of 163.37 degrees C and within 4.15 hrs. Under these conditions, the conversion will be above 97.94%. These conditions have been applied to adjust the process of transesterification of waste cooking oil. The reusability of the Cu0.4Zn0.6Al2O4 nanocatalyst in the esterification reaction was investigated in this study. Employed statistical techniques and developed models can be employed as a useful tool for design, prediction, and optimization of the biodiesel production process with effective performance for various industrial applications. (c) 2021 Society of Chemical Industry (SCI).
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| 11. |
- Hsieh, Yves S-Y, et al.
(författare)
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Structure and bioactivity of the polysaccharides in medicinal plant Dendrobium huoshanense
- 2008
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Ingår i: Bioorganic & Medicinal Chemistry. - : Elsevier. - 0968-0896 .- 1464-3391. ; 16:11, s. 6054-68
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Tidskriftsartikel (refereegranskat)abstract
- Detailed structures of the active polysaccharides extracted from the leaf and stem cell walls and mucilage of Dendrobium huoshanense are determined by using various techniques, including chromatographic, spectroscopic, chemical, and enzymatic methods. The mucilage polysaccharide exhibits specific functions in activating murine splenocytes to produce several cytokines including IFN-gamma, IL-10, IL-6, and IL-1alpha, as well as hematopoietic growth factors GM-CSF and G-CSF. However, the deacetylated mucilage obtained from an alkaline treatment fails to induce cytokine production. The structure and bioactivity of mucilage components are validated by further fractionation. This is the first study that provides clear evidence for the structure and activity relationship of the polysaccharide in D. huoshanense.
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| 12. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 13. |
- Lai, Kuei-Hung, et al.
(författare)
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Antileukemic Scalarane Sesterterpenoids and Meroditerpenoid from Carteriospongia (Phyllospongia) sp., Induce Apoptosis via Dual Inhibitory Effects on Topoisomerase II and Hsp90
- 2016
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Two new scalarane sesterterpenoids, 12 beta-(3'beta-hydroxybutanoyloxy)-20,24-dimethyl-24-oxo-scalara-16-en-25-al (1) and 12 beta-(3'beta-hydroxypentanoyloxy)-20,24-dimethyl-24-oxo-scalara-16-en-25-al (2), along with one known tetraprenyltoluquinol-related metabolite (3), were isolated from the sponge Carteriospongia sp. In leukemia Molt 4 cells, 1 at 0.0625 mu g/mL (125 nM) triggered mitochondrial membrane potential (MMP) disruption and apoptosis showing more potent effect than 2 and 3. The isolates inhibited topoisomerase II alpha expression. The apoptotic-inducing effect of 3 was supported by the in vivo experiment through suppressing the volume of xenograft tumor growth (47.58%) compared with the control. Compound 1 apoptotic mechanism of action in Molt 4 cells was further elucidated through inducing ROS generation, calcium release and ER stress. Using the molecular docking analysis, 1 exhibited more binding affinity to N-terminal ATP-binding pocket of Hsp90 protein than 17-AAG, a standard Hsp90 inhibitor. The expression of Hsp90 client proteins, Akt, p70(S6k), NF kappa B, Raf-1, p-GSK3 beta, and XIAP, MDM 2 and Rb2, and CDK4 and Cyclin D3, HIF1 and HSF1 were suppressed by the use of 1. However, the expression of Hsp70, acetylated tubulin, and activated caspase 3 were induced after 1 treatment. Our results suggested that the proapoptotic effect of the isolates is mediated through the inhibition of Hsp90 and topoisomerase activities.
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| 14. |
- Lee, Mengshan, et al.
(författare)
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Water-energy nexus for urban water systems : A comparative review on energy intensity and environmental impacts in relation to global water risks
- 2017
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 205, s. 589-601
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Tidskriftsartikel (refereegranskat)abstract
- The importance of the interdependence between water and energy, also known as the water-energy nexus, is well recognized. The water-energy nexus is typically characterized in resource use efficiency terms such as energy intensity. This study aims to explore the quantitative results of the nexus in terms of energy intensity and environmental impacts (mainly greenhouse gas emissions) on existing water systems within urban water cycles. We also characterized the influence of water risks on the water-energy nexus, including baseline water stress (a water quantity indicator) and return flow ratio (a water quality indicator). For the 20 regions and 4 countries surveyed (including regions with low to extremely high water risks that are geographically located in Africa, Australia, Asia, Europe, and North America), their energy intensities were positively related to the water risks. Regions with higher water risks were observed to have relatively higher energy and GHG intensities associated with their water supply systems. This mainly reflected the major influence of source water accessibility on the nexus, particularly for regions requiring energy-intensive imported or groundwater supplies, or desalination. Regions that use tertiary treatment (for water reclamation or environmental protection) for their wastewater treatment systems also had relatively higher energy and GHG emission intensities, but the intensities seemed to be independent from the water risks. On-site energy recovery (e.g., biogas or waste heat) in the wastewater treatment systems offered a great opportunity for reducing overall energy demand and its associated environmental impacts. Future policy making for the water and energy sectors should carefully consider the water energy nexus at the regional or local level to achieve maximum environmental and economic benefits. The results from this study can provide a better understanding of the water-energy nexus and informative recommendations for future policy directions for the effective management of water and energy.
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| 15. |
- Lin, Chia-Yeh, et al.
(författare)
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H2B Mono-ubiquitylation Facilitates Fork Stalling and Recovery during Replication Stress by Coordinating Rad53 Activation and Chromatin Assembly
- 2014
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Ingår i: PLOS Genetics. - : Public library science. - 1553-7390 .- 1553-7404. ; 10:10, s. e1004667-
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Tidskriftsartikel (refereegranskat)abstract
- The influence of mono-ubiquitylation of histone H2B (H2Bub) on transcription via nucleosome reassembly has been widely documented. Recently, it has also been shown that H2Bub promotes recovery from replication stress; however, the underling molecular mechanism remains unclear. Here, we show that H2B ubiquitylation coordinates activation of the intra-S replication checkpoint and chromatin re-assembly, in order to limit fork progression and DNA damage in the presence of replication stress. In particular, we show that the absence of H2Bub affects replication dynamics (enhanced fork progression and reduced origin firing), leading to γH2A accumulation and increased hydroxyurea sensitivity. Further genetic analysis indicates a role for H2Bub in transducing Rad53 phosphorylation. Concomitantly, we found that a change in replication dynamics is not due to a change in dNTP level, but is mediated by reduced Rad53 activation and destabilization of the RecQ helicase Sgs1 at the fork. Furthermore, we demonstrate that H2Bub facilitates the dissociation of the histone chaperone Asf1 from Rad53, and nucleosome reassembly behind the fork is compromised in cells lacking H2Bub. Taken together, these results indicate that the regulation of H2B ubiquitylation is a key event in the maintenance of genome stability, through coordination of intra-S checkpoint activation, chromatin assembly and replication fork progression.
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| 16. |
- Liu, Chia-Chuan, et al.
(författare)
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Geochemical characteristics of the mud volcano fluids in southwestern Taiwan and their possible linkage to elevated arsenic concentration in Chianan plain groundwater
- 2012
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Ingår i: ENVIRONMENTAL EARTH SCIENCES. - : Springer Science and Business Media LLC. - 1866-6280 .- 1866-6299. ; 66:5, s. 1513-1523
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Tidskriftsartikel (refereegranskat)abstract
- Fluid and mud samples were collected from Wushanting (WST), Hsiaokunshui (HKS), Yenshuikeng (YSK), Kuantzeling (KZL), and Kunshuiping (KSP) mud volcanoes of southwestern Taiwan. Concentrations of major ions and trace elements in mud volcanic fluids were analyzed to find the possible linkage to elevated arsenic (As) concentrations in the Chianan plain groundwater. The elevated Na+, K+, and Cl- concentrations indicated possible marine origin of the fluids. The trace element concentrations in the mud volcanic fluids were generally low, but the As concentrations were up to 0.12 mg/L. High contents of As, Fe, and Mn were observed in the mud samples. Saturation index calculations indicated that both carbonate and oxide minerals acted as potential sinks for As in the mud volcanic fluids. Arsenic in the dewatering fluids and muds may be transported by the subsurface flow and surface streams as suspended solids and eventually deposited in the Chianan plain aquifers. Under reducing conditions, As may be released from the host minerals (such as Fe- and Mn-oxides/hydroxides), thereby causing widespread groundwater As pollution.
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| 17. |
- Rani Singhania, Reeta, et al.
(författare)
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Role and significance of lytic polysaccharide monooxygenases (LPMOs) in lignocellulose deconstruction
- 2021
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Ingår i: Bioresource Technology. - : Elsevier BV. - 0960-8524 .- 1873-2976. ; 335
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Forskningsöversikt (refereegranskat)abstract
- Lytic polysaccharide monooxygenases (LPMOs) emerged a decade ago and have been described as biomass deconstruction boosters as they play an extremely important role in unravelling the enzymatic biomass hydrolysis scheme. These are oxidative enzymes requiring partners to donate electrons during catalytic action on cellulose backbone. Commercial cellulase preparations are mostly from the robust fungal sources, hence LPMOs from fungi (AA9) have been discussed. Characterisation of LPMOs suffers due to multiple complications which has been discussed and challenges in detection of LPMOs in secretomes has also been highlighted. This review focuses on the significance of LPMOs on biomass hydrolysis due to which it has become a key component of cellulolytic cocktail available commercially for biomass deconstruction and its routine analysis challenge has also been discussed. It has also outlined a few key points that help in expressing catalytic active recombinant AA9 LPMOs.
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| 18. |
- Wang, Bo-Yao, et al.
(författare)
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Nonlinear bandgap opening behavior of BN co-doped graphene
- 2016
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Ingår i: Carbon. - : Elsevier. - 0008-6223 .- 1873-3891. ; 107, s. 857-864
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Tidskriftsartikel (refereegranskat)abstract
- We have demonstrated a nonlinear behavior for the bandgap opening of doped graphene by controlling the concentration of B and N co-dopants. X-ray absorption and emission spectra reveal that the bandgap increases from 0 to 0.6 eV as the concentration of BN dopants is increased from 0 to 6%, while the bandgap closes when the doping concentration becomes 56%. This nonlinear behavior of bandgap opening of the BN-doped graphene depending on the BN concentrations is consistent with the valenceband photoemission spectroscopic measurements. The spatially resolved B, N and C K-edge scanning transmission x-ray microscopy and their x-ray absorption near- edge structure spectra all support the scenario of the development of h-BN-like domains at high concentrations of BN. Ab initio calculation, by taking into account of the strong correlation between the bandgap and the geometry/concentration of the dopant, has been performed with various BN-dopant nano-domains embedded in the graphene monolayer to verify the unique bandgap behavior. Based on the experimental measurements and ab initio calculation, we propose the progressive formation of a phase-separated zigzag-edged BN domain from BN quantum dots with increasing BN-dopant concentration to explain the extraordinary nonlinear behavior of bandgap opening of BN-doped graphene sheets. This study reveals a new way to engineer the bandgap of low-dimensional systems.
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| 19. |
- Wu, Ping-Hsun, et al.
(författare)
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A Low Ankle-Brachial Index and High Brachial-Ankle Pulse Wave Velocity Are Associated with Poor Cognitive Function in Patients Undergoing Hemodialysis
- 2019
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Ingår i: Disease Markers. - : Hindawi Limited. - 0278-0240 .- 1875-8630. ; 2019
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Tidskriftsartikel (refereegranskat)abstract
- Patients with end-stage renal disease (ESRD) have an increased risk of both impaired cognitive function and peripheral artery disease (PAD) than the general population. The association between PAD and dementia is recognized, but there are limited studies in patients with ESRD. The aim of this study was to evaluate the relationship between ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) and cognitive impairment in patients receiving hemodialysis (HD). We enrolled 136 prevalent HD patients (mean age 59.3 +/- 10.5 years, 55.9% male). Cognitive performance was measured using the Montreal Cognitive Assessment (MoCA) and Cognitive Abilities Screening Instrument (CASI) by trained psychiatrists. Associations between the cognitive function and ABI and baPWV were assessed using multiple linear regression analysis. Compared with HD patients with ABI >= 0.9, patients with ABI<0.9 had lower MoCA score (p=0.027) and lower CASI score but did not achieve significant level (p=0.056). In the multivariate stepwise linear regression analysis, ABI (per 0.1) was independently positively associated with the MoCA score (beta coefficient=0.62, p=0.011) and the CASI score (beta coefficient=1.43, p=0.026). There is a negative association between baPWV (per 100cm/s) and CASI (beta coefficient=-0.70, p=0.009). In conclusion, a low ABI or high baPWV was associated with a lower cognitive function in HD patients.
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| 20. |
- Wu, Ping-Hsun, et al.
(författare)
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Association between Circulation Indole-3-Acetic Acid Levels and Stem Cell Factor in Maintenance Hemodialysis Patients : A Cross-Sectional Study
- 2020
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Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 9:1
-
Tidskriftsartikel (refereegranskat)abstract
- Protein-bound uremic toxin is a cardiovascular (CV) risk factor for patients with end-stage renal disease. Indole-3-acetic acid (IAA) was found to be associated with CV disease but the detailed pathophysiology remains unknown. Moreover, mitogen-activated protein kinase (MAPK) signaling cascades play an important role in the pathogenesis of CV disease. Thus, we explored the association between circulating IAA levels and forty MAPK cascade associated proteins in patients undergoing hemodialysis (HD). Circulating total form IAA was quantified by mass spectrometry and forty MAPK cascade associated proteins by a proximity extension assay in 331 prevalent HD patients. Accounting for multiple testing, and in multivariable-adjusted linear regression models, circulating total form IAA levels were positively associated with stem cell factor (beta coefficient 0.13, 95% confidence interval 0.04 to 0.21, p = 0.004). A bioinformatics approach using the search tool for interactions of chemicals (STITCH) tool provided information that IAA may be involved in the regulation of cell proliferation, hematopoietic cells, and the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway. The knowledge gained here can be generalized, thereby impacting the non-traditional CV risk factors in patients with kidney disease. Further in vitro work is necessary to validate the translation of the mechanistic pathways.
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| 21. |
- Xu, Jing-Hao, et al.
(författare)
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Briaviolides K-N, New Briarane-Type Diterpenoids from Cultured Octocoral Briareum violaceum
- 2018
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Ingår i: Marine Drugs. - : MDPI. - 1660-3397. ; 16:3
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Tidskriftsartikel (refereegranskat)abstract
- Four new briarane diterpenoids, briaviolides K-N (1-4), have been obtained from the cultured-type octocoral Briareum violaceum. Using a spectroscopic approach, the structures of briaranes 1-4 were identified. This study employed an in vitro model of lipopolysaccharide (LPS)-induced inflammation in the murine macrophage RAW264.7 cell line, and found that among the four briaranes, briarane 2 possessed anti-inflammatory activity against inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expressions in cells. In addition, principal component analysis using the chemical global positioning system (ChemGPS) for natural products (ChemGPS-NP) was employed in order to analyze the structure-activity relationship (SAR), and the results indicated that the ring conformation of the compound has a leading role in suppressing the expressions of pro-inflammatory iNOS and COX-2 proteins in macrophages.
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- Zou, Zhi, 1989-
(författare)
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Capacitive Mixing for Extracting Concentration Gradient Energy
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Capacitive mixing (CapMix) is a renewable method of extracting energy from the salinity gradient energy (SGE) between seawater and freshwater. The classical CapMix systems using solid electrodes generate electricity by periodically circulating seawater and freshwater into the CapMix system. The major limitation of classical CapMix is intermittent energy production. Therefore, the development of a new CapMix system to solve this limitation is highly desired. This thesis aims to develope an innovative CapMix system for continuous energy production. All the work is based on four papers and can be divided into the following parts.In Chapter 1, a brief introduction to the SGE and CapMix is presented. In Chapter 2, a comparative study on the four classical CapMix systems, namely, capacitive energy extraction based on double layer expansion (CDLE), capacitive energy extraction based on the Donnan potential (CDP), and CDP with additional charging of constant voltage (CDP-CV) and constant current (CDP-CC)., is discussed. The influences of experimental parameters, e.g., applied voltage, applied current, accumulated charge, and the external load on the system performance, were systematically investigated and presented. A comprehensive comparison between these four classical CapMix systems is also given in this chapter.Chapter 3 and Chapter 4 describe two novel CapMix systems based on flow electrode (F-CapMix) configuration which were developed to realize continuous energy production. The first one is a two-cell F-CapMix system, in which the flow electrode slurry was circulated between the two cells. The second is a one-cell F-CapMix system with cross chambers, in which there are two chambers between one pair of plates in parallel; the flow electrode slurry was circulated within the two graphite plates of the cell. The feasibility of these two F-CapMix systems was examined. The effect of the experimental parameters, e.g., activated carbon loading, carbon black amount, external resistance, feedwater flow rate, and flow electrode flow rate, on the system performance were systematically investigated and presented. In Chapter 5, a thorough study of the theoretical models related to the thermodynamic properties of the electric double layer at equilibrium, e.g., the Gouy-Chapman-Stern (GCS), Modified Poisson-Boltzmann-Stern (MPBS), modified Donnan (mD) and improved modified Donnan (i-mD) models is presented. The rationality and the physical interpretation of the parameters used in these models were detailed investigated and presented.
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