| 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. |
- Liu, Fangcen, et al.
(författare)
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Biocompatible Nanoparticles as a Platform for Enhancing Antitumor Efficacy of Cisplatin-Tetradrine Combination
- 2021
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Ingår i: Nanoscale Research Letters. - : Springer. - 1931-7573 .- 1556-276X. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Combination therapy has been a standard strategy in the clinical tumor treatment. We have demonstrated that combination of Tetradrine (Tet) and Cisplatin (CDDP) presented a marked synergistic anticancer activity, but inevitable side effects limit their therapeutic concentration. Considering the different physicochemical and pharmacokinetic properties of the two drugs, we loaded them into a nanovehicle together by the improved double emulsion method. The nanoparticles (NPs) were prepared from the mixture of poly(ethyleneglycol)-polycaprolactone (PEG-PCL) and polycarprolactone (HO-PCL), so CDDP and Tet can be located into the NPs simultaneously, resulting in low interfering effect and high stability. Images from fluorescence microscope revealed the cellular uptake of both hydrophilic and hydrophobic agents delivered by the NPs. In vitro studies on different tumor cell lines and tumor tissue revealed increased tumor inhibition and apoptosis rates. As to the in vivo studies, superior antitumor efficacy and reduced side effects were observed in the NPs group. Furthermore, (18)FDG-PET/CT imaging demonstrated that NPs reduced metabolic activities of tumors more prominently. Our results suggest that PEG-PCL block copolymeric NPs could be a promising carrier for combined chemotherapy with solid efficacy and minor side effects.
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| 3. |
- Yen, Ying-Tzu, et al.
(författare)
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Prominent Enhancement of Cisplatin Efficacy with Optimized Methoxy Poly(ethylene glycol)-Polycaprolactone Block Copolymeric Nanoparticles
- 2020
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Ingår i: Journal of Biomedical Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1550-7033 .- 1550-7041. ; 16:3, s. 335-343
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Tidskriftsartikel (refereegranskat)abstract
- Chemotherapy has been one of the major standard treatments for a variety of cancers. cis-Dichlorodiamminoplatiunum(II) (cisplatin, CDDP), as one of the anticancer agents, demonstrated excellent efficacy against tumor and has been an indispensable component in chemotherapy, chemoradiation, chemo-molecular targeted therapy and chemo-immunotherapy. However, its therapeutic concentration was limited since its inevitable toxicity. Previously, we have constructed CDDP-loaded nanoparticles (NPs) with mixture of poly(ethyleneglycol)-polycaprolactone (PEG-PCL) and polycarprolactone (HO-PCL) by a facile method. The most optimal proportion of the two copolymers was selected through a series of physical, chemical, cytological and histological evaluations. In the present study, we explored the mechanisms of NPs and observed the in vivo antitumor effect after administrating CDDP-loaded PEG-PCL NPs. Positron emission tomography as well as computed tomography (PET/CT) were adopted for detecting tumoral metabolic activity. Images from fluorescence microscope revealed superior cellular uptake of CDDP-loaded NPs with rhodamine B aggregated intracellularly in cancer cells. Similar apoptotic rates between free CDDP group and CDDP-loaded NPs group was measured by flow cytometry. Tumor volumes and murine weights confirmed the superiority of CDDP-loaded NPs in therapeutic efficacy as compared with free CDDP. Blood tests showed milder side effects in CDDP-loaded nanoparticle group. PET/CT images illustrated less uptake intensity of FDG in mice received CDDP-loaded NPs than free CDDP. Our results suggest that PEG-PCL/PCL NPs could be a promising antitumor drug carrier for CDDP delivery with solid efficacy and minor side effects.
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| 4. |
- Abdollahi, Anna M., et al.
(författare)
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Comparison of actigraphy-measured and parent-reported sleep in association with weight status among preschool children
- 2024
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Ingår i: Journal of Sleep Research. - : John Wiley & Sons. - 0962-1105 .- 1365-2869. ; 33:1
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Tidskriftsartikel (refereegranskat)abstract
- This study compared weekday and weekend actigraphy-measured and parent-reported sleep in relation to weight status among preschool-aged children. Participants were 3–6 years old preschoolers from the cross-sectional DAGIS-study with sleep data for ≥2 weekday and ≥2 weekend nights. Parents-reported sleep onset and wake-up times were gathered alongside 24 h hip-worn actigraphy. An unsupervised Hidden-Markov Model algorithm provided actigraphy-measured night time sleep without the guidance of reported sleep times. Waist-to-height ratio and age-and-sex-specific body mass index characterised weight status. Comparison of methods were assessed with consistency in quintile divisions and Spearman correlations. Associations between sleep and weight status were assessed with adjusted regression models. Participants included 638 children (49% girls) with a mean ± SD age of 4.76 ± 0.89. On weekdays, 98%–99% of actigraphy-measured and parent-reported sleep estimates were classified in the same or adjacent quintile and were strongly correlated (rs = 0.79–0.85, p < 0.001). On weekends, 84%–98% of actigraphy-measured and parent-reported sleep estimates were respectively classified and correlations were moderate to strong (rs = 0.62–0.86, p < 0.001). Compared with actigraphy-measured sleep, parent-reported sleep had consistently earlier onset, later wake-up, and greater duration. Earlier actigraphy-measured weekday sleep onset and midpoint were associated with a higher body mass index (respective β-estimates: −0.63, p < 0.01 and −0.75, p < 0.01) and waist-to-height ratio (−0.004, p = 0.03 and −0.01, p = 0.02). Though the sleep estimation methods were consistent and correlated, actigraphy measures should be favoured as they are more objective and sensitive to identifying associations between sleep timing and weight status compared with parent reports.
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| 5. |
- An, Li, et al.
(författare)
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Challenges, tasks, and opportunities in modeling agent-based complex systems
- 2021
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Ingår i: Ecological Modelling. - : Elsevier BV. - 0304-3800 .- 1872-7026. ; 457
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Forskningsöversikt (refereegranskat)abstract
- Humanity is facing many grand challenges at unprecedented rates, nearly everywhere, and at all levels. Yet virtually all these challenges can be traced back to the decision and behavior of autonomous agents that constitute the complex systems under such challenges. Agent-based modeling has been developed and employed to address such challenges for a few decades with great achievements and caveats. This article reviews the advances of ABM in social, ecological, and socio-ecological systems, compare ABM with other traditional, equation-based models, provide guidelines for ABM novice, modelers, and reviewers, and point out the challenges and impending tasks that need to be addressed for the ABM community. We further point out great opportunities arising from new forms of data, data science and artificial intelligence, showing that agent behavioral rules can be derived through data mining and machine learning. Towards the end, we call for a new science of Agent-based Complex Systems (ACS) that can pave an effective way to tackle the grand challenges.
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| 6. |
- An, Li, et al.
(författare)
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Modeling agent decision and behavior in the light of data science and artificial intelligence
- 2023
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Ingår i: Environmental Modelling & Software. - 1364-8152 .- 1873-6726. ; 166
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Tidskriftsartikel (refereegranskat)abstract
- Agent-based modeling (ABM) has been widely used in numerous disciplines and practice domains, subject to many eulogies and criticisms. This article presents key advances and challenges in agent-based modeling over the last two decades and shows that understanding agents' behaviors is a major priority for various research fields. We demonstrate that artificial intelligence and data science will likely generate revolutionary impacts for science and technology towards understanding agent decisions and behaviors in complex systems. We propose an innovative approach that leverages reinforcement learning and convolutional neural networks to equip agents with the intelligence of self-learning their behavior rules directly from data. We call for further developments of ABM, especially modeling agent behaviors, in the light of data science and artificial intelligence.
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| 7. |
- Hu, Min, et al.
(författare)
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Defective uterine spiral artery remodelling and placental senescence in a pregnant rat model of polycystic ovary syndrome. : Impaired SpA remodelling in PCOS
- 2023
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Ingår i: The American journal of pathology. - 1525-2191. ; 193:12, s. 1916-1935
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Tidskriftsartikel (refereegranskat)abstract
- Pregnancy-related problems have been linked to impairments in maternal uterine spiral artery (SpA) remodelling. The mechanisms underlying this association are still unclear, as are whether hyperandrogenism and insulin resistance - the two common manifestations of polycystic ovary syndrome (PCOS) - affect uterine SpA remodelling. This study verified previous work in which exposure to 5-dihydrotestosterone (DHT) and insulin (INS) in rats during pregnancy resulted in hyperandrogenism, insulin intolerance, and higher foetal mortality. It also found that exposure to DHT and INS dysregulated the expression of angiogenesis-related genes in the uterus and placenta. It also decreased expression of endothelial nitric oxide synthase and matrix metallopeptidases 2 and 9, increased fibrotic collagen deposits in the uterus, and reduced expression of marker genes for SpA-associated trophoblast giant cells. These changes were related to a greater proportion of un-remodelled uterine SpAs and a smaller proportion of highly remodelled arteries in DHT+INS-exposed rats. Placentas from DHT+INS-exposed rats exhibited decreased basal and labyrinth zone regions, reduced maternal blood spaces, diminished labyrinth vascularity, and an imbalance in the abundance of vascular and smooth muscle proteins. Furthermore, placentas from DHT+INS-exposed rats showed expression of placental insufficiency markers and a significant increase in cell senescence-associated protein levels. Altogether, this work demonstrates increased pregnancy complications in PCOS may be mediated by problems with uterine SpA remodelling, placental functionality, and placental senescence.
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| 8. |
- Li, Siyu, et al.
(författare)
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Effects of surface treatment and shade on the color, translucency, and surface roughness of high-translucency self-glazed zirconia materials
- 2022
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Ingår i: The Journal of prosthetic dentistry (Print). - : Elsevier. - 0022-3913 .- 1097-6841. ; 128:2
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Tidskriftsartikel (refereegranskat)abstract
- Statement of problemThe impact of different surface treatments and shades on the color, translucency, and surface roughness of high-translucency self-glazed zirconia materials is unclear.PurposeThe purpose of this in vitro study was to investigate the effects of different external surface treatments (self-glazed, milled, polished, and glazed), intaglio surface treatments (milled and airborne-particle abraded), and shades (A1 and A3 shades) on the color, translucency, and surface roughness of high-translucency self-glazed zirconia materials, as well as the correlations among optical parameters, translucency, and surface roughness.Material and methodsEighty shade A1 and 80 shade A3 disks were fabricated with a thickness of 0.80 +/- 0.02 mm and divided into 16 groups (n=10). Different external and intaglio surface treatments were applied to the specimens. CIELab values were measured with a spectrophotometer, and color differences (Delta E-00) and relative translucency parameter (RTP) were calculated. Total transmittance (Tt%) and reflectance (R%) were tested with a spectrophotometer equipped with an integrating sphere. Surface roughness (Ra and Rz) (mu m) was measured with a noncontact 3-dimensional laser scanning microscope. One specimen from each group was subjected to scanning electron microscope (SEM) examination. Data were analyzed with ANOVA and the Tukey post hoc test. The correlation among optical parameters, translucency, and surface roughness was investigated by using Pearson correlation analysis (alpha=.05).ResultsThe effects of external surface treatments, intaglio airborne-particle abrasion, and shades on Delta E-00, RTP, and Ra values of the disks were significantly different (P<.001). The smoothest external polishing surface had the greatest RTP and color difference (P<.001). Shade A3 disks had lower RTP and Tt% values than shade A1 disks (P<.001). Delta E-00 had a highly positive relationship with the RTP (A1: r=0.884, P<.001; A3: r=0.859, P<.001). SEM images demonstrated that surface treatments affected the surface texture of monolithic zirconia ceramics.ConclusionsDifferent surface treatments affected the surface roughness, translucency, and final color of zirconia materials. The smoothest external polishing surface had the greatest RTP and color difference. Different shades influenced the translucency, as the darker the disk shade, the lower the translucency. The RTP was appropriate as an auxiliary indicator for evaluating the color of a dental ceramic.
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| 9. |
- Li, Yuhong, et al.
(författare)
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Context-aware data dissemination for ICN-based vehicular ad hoc networks
- 2018
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Ingår i: Information. - : MDPI AG. - 2078-2489. ; 9:11
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Tidskriftsartikel (refereegranskat)abstract
- Information-centric networking (ICN) technology matches many major requirements of vehicular ad hoc networks (VANETs) in terms of its connectionless networking paradigm accordant with the dynamic environments of VANETs and is increasingly being applied to VANETs. However, wireless transmissions of packets in VANETs using ICN mechanisms can lead to broadcast storms and channel contention, severely affecting the performance of data dissemination. At the same time, frequent changes of topology due to driving at high speeds and environmental obstacles can also lead to link interruptions when too few vehicles are involved in data forwarding. Hence, balancing the number of forwarding vehicular nodes and the number of copies of packets that are forwarded is essential for improving the performance of data dissemination in information-centric networking for vehicular ad-hoc networks. In this paper, we propose a context-aware packet-forwarding mechanism for ICN-based VANETs. The relative geographical position of vehicles, the density and relative distribution of vehicles, and the priority of content are considered during the packet forwarding. Simulation results show that the proposed mechanism can improve the performance of data dissemination in ICN-based VANET in terms of a successful data delivery ratio, packet loss rate, bandwidth usage, data response time, and traversed hops.
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| 10. |
- Li, Yuhong, et al.
(författare)
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Distance Assisted Information Dissemination with Broadcast Suppression for ICN-based VANET
- 2016
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Konferensbidrag (refereegranskat)abstract
- Information-centric networking (ICN) is being applied to the vehicular networks by more and more researchers on account of its lightweight and connectionless networking paradigm and in-network caching characteristics, making it suitable for the dynamic environments of vehicular networks. However, wireless transmission of interest packets to find content in the network may lead to broadcast storms that can affect the performance of information dissemination severely. This paper proposes a distance assisted data dissemination method with broadcast storm suppressing mechanism (DASB) for supporting rapid and efficient information dissemination in ICN-based vehicular ad hoc networks (VANETs). Geo-position data of vehicles are used to accelerate packet forwarding, and vehicular nodes in certain areas are restricted to forward packets in order to suppress the broadcast storm. Simulation results show that the proposed method can greatly reduce the total number of packets transmitted in the network, and the successful information delivery ratio and information delivery time can also be improved.
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