GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • MDPI AG  (47)
  • English  (47)
  • 1
    Online Resource
    Online Resource
    Tivantinib, A c-Met Inhibitor in Clinical Trials, Is Susceptible to ABCG2-Mediated Drug Resistance
    MDPI AG ; 2020
    In:  Cancers Vol. 12, No. 1 ( 2020-01-12), p. 186-
    Details
    In: Cancers, MDPI AG, Vol. 12, No. 1 ( 2020-01-12), p. 186-
    Abstract: Tivantinib, also known as ARQ-197, is a potent non-ATP competitive selective c-Met inhibitor currently under phase 3 clinical trial evaluation for liver and lung cancers. In this study, we explored factors that may lead to tivantinib resistance, especially in regards to its interaction with ATP-binding cassette super-family G member 2 (ABCG2). ABCG2 is one of the most important members of the ATP-binding cassette (ABC) transporter family, a group of membrane proteins that play a critical role in mediating multidrug resistance (MDR) in a variety of cancers, including those of the liver and lung. Tivantinib received a high score in docking analysis, indicating a strong interaction between tivantinib and ABCG2, and an ATPase assay indicated that tivantinib stimulated ABCG2 ATPase activity in a concentration-dependent manner. An MTT assay showed that ABCG2 overexpression significantly desensitized both the cancer cells and ABCG2 transfected-HEK293 cells to tivantinib and that this drug resistance can be reversed by ABCG2 inhibitors. Furthermore, tivantinib upregulated the protein expression of ABCG2 without altering the cell surface localization of ABCG2, leading to increased resistance to substrate drugs, such as mitoxantrone. Altogether, these data demonstrate that tivantinib is a substrate of ABCG2, and, therefore, ABCG2 overexpression may decrease its therapeutic effect. Our study provides evidence that the overexpression of ABCG2 should be monitored in clinical settings as an important risk factor for tivantinib drug resistance.
    Type of Medium: Online Resource
    ISSN: 2072-6694
    URL: Article
    DOI: 10.3390/cancers12010186
    Language: English
    Publisher: MDPI AG
    Publication Date: 2020
    detail.hit.zdb_id: 2527080-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Liposomal Vitamin D3 as an Anti-aging Agent for the Skin
    MDPI AG ; 2019
    In:  Pharmaceutics Vol. 11, No. 7 ( 2019-07-03), p. 311-
    Details
    In: Pharmaceutics, MDPI AG, Vol. 11, No. 7 ( 2019-07-03), p. 311-
    Abstract: Vitamin D3 is an effective skin protective substance to prevent photoaging. Liposomes were used as a carrier to deliver vitamin D3 to improve the stability and to enhance the treatment effect of vitamin D3. The stability of vitamin D3 liposomes, average cumulative penetration, and retention of vitamin D3 in the skin were then evaluated and compared with free vitamin D3. Finally, the treatment effect of vitamin D3 liposomes in a rat photoaging model was appraised and Haematoxylin-Eosin (H & E) staining was used to assess the histology changes of the skin after vitamin D3 liposome treatment. The results indicated that liposomes could significantly improve the stability of vitamin D3. The average skin retention of vitamin D3 liposomes was 1.65 times that of the vitamin D3 solution. Vitamin D3 liposomes could repair the surface morphology of skin in the photoaging model and promote the production of new collagen fibers. Vitamin D3 liposomes as a potential skin care agent could significantly improve skin appearance and repair damage in the histology of photoaging.
    Type of Medium: Online Resource
    ISSN: 1999-4923
    URL: Article
    DOI: 10.3390/pharmaceutics11070311
    Language: English
    Publisher: MDPI AG
    Publication Date: 2019
    detail.hit.zdb_id: 2527217-2
    SSG: 15,3
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Achievement of Both Mechanical Properties and Intrinsic Self-Healing under Body Temperature in Polyurethane Elastomers: A Synthesis Strategy from Waterborne Polymers
    MDPI AG ; 2020
    In:  Polymers Vol. 12, No. 4 ( 2020-04-24), p. 989-
    Details
    In: Polymers, MDPI AG, Vol. 12, No. 4 ( 2020-04-24), p. 989-
    Abstract: Inspired by the growing demand for smart and environmentally friendly polymer materials, we employed 2,2′-disulfanediyldianiline (22DTDA) as a chain extender to synthesize a waterborne polyurethane (WPUR). Due to the ortho-substituted structure of the aromatic disulfide, the urea moieties formed a unique microphase structure in the WPUR, its mechanical strength was enhanced more 180 times relative to that of the material prepared without 22DTDA, and excellent self-healing abilities at body temperature in air or under ultrasound in water were obtained. If the self-healing process was carried out at 37 °C, 50 °C or under ultrasound, the ultimate tensile strength and elongation at break of the healed film could reach 13.8 MPa and 1150%, 15.4 MPa and 1215%, or 16 MPa and 1056%, respectively. Moreover, the WPUR films could be re-healed at the same fracture location over three cutting–healing cycles, and the recovery rates of the tensile strength and elongation at break remained almost constant throughout these cycles.
    Type of Medium: Online Resource
    ISSN: 2073-4360
    URL: Article
    DOI: 10.3390/polym12040989
    Language: English
    Publisher: MDPI AG
    Publication Date: 2020
    detail.hit.zdb_id: 2527146-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Spatial and Temporal Changes of Urban Built-Up Area in the Yellow River Basin from Nighttime Light Data
    MDPI AG ; 2022
    In:  Land Vol. 11, No. 7 ( 2022-07-13), p. 1067-
    Details
    In: Land, MDPI AG, Vol. 11, No. 7 ( 2022-07-13), p. 1067-
    Abstract: Nighttime light (NTL) images obtained by the Visible Infrared Imaging Radiometer (VIIRS) mounted on the National Polar-orbiting Partnership (NPP) could objectively represent human activities and instantly identify urban shapes on a temporal and spatial scale. From 2013 to 2020, the built-up areas of eight provincial capital cities were extracted using NPP/VIIRS NTL data to examine the dynamic changes in city expansion and socioeconomic development in the Yellow River Basin during the urbanization process. The spatial characteristics of urban built-up area expansion were generated using the eight-quadrant analysis method and combined with the statistical data of population and (gross domestic product) GDP to analyze the correlations between the light intensity of built-up areas, population and GDP; this enables an understanding of the changes in population and economy in the development of urban built-up area expansion. The findings show that: (1) unbalanced city development existed in the Yellow River Basin’s upper, middle, and lower reaches, and the expansion and light intensity of cities in the upper reaches were slower than those in the middle and lower reaches; (2) the spatial differentiation of urban expansion was significant between each of the reaches in the Yellow River Basin, and greatly influenced by natural geographical elements; and (3) positive correlation exists between light intensity, population, and GDP in the built-up areas of the middle and lower reaches, while the correlations in the upper reaches were not stable. In conclusion, light data indirectly reflects urban development and could be used as a substitute variable for socioeconomic development indicators under certain conditions.
    Type of Medium: Online Resource
    ISSN: 2073-445X
    URL: Article
    DOI: 10.3390/land11071067
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2682955-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Pathogenesis and Therapeutic Strategies Related to Non-Alcoholic Fatty Liver Disease
    MDPI AG ; 2022
    In:  International Journal of Molecular Sciences Vol. 23, No. 14 ( 2022-07-16), p. 7841-
    Details
    In: International Journal of Molecular Sciences, MDPI AG, Vol. 23, No. 14 ( 2022-07-16), p. 7841-
    Abstract: Non-alcoholic fatty liver disease (NAFLD), one of the most common types of chronic liver disease, is strongly correlated with obesity, insulin resistance, metabolic syndrome, and genetic components. The pathological progression of NAFLD, consisting of non-alcoholic fatty liver (NAFL), non-alcoholic steatohepatitis (NASH), and liver cirrhosis, is characterized by a broad spectrum of clinical phenotypes. Although patients with mild NAFL are considered to show no obvious clinical symptoms, patients with long-term NAFL may culminate in NASH and further liver fibrosis. Even though various drugs are able to improve NAFLD, there are no FDA-approved medications that directly treat NAFLD. In this paper, the pathogenesis of NAFLD, the potential therapeutic targets, and their underlying mechanisms of action were reviewed.
    Type of Medium: Online Resource
    ISSN: 1422-0067
    URL: Article
    DOI: 10.3390/ijms23147841
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2019364-6
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Polyphenols Derived from Lychee Seed Suppress Aβ (1-42)-Induced Neuroinflammation
    MDPI AG ; 2018
    In:  International Journal of Molecular Sciences Vol. 19, No. 7 ( 2018-07-20), p. 2109-
    Details
    In: International Journal of Molecular Sciences, MDPI AG, Vol. 19, No. 7 ( 2018-07-20), p. 2109-
    Abstract: Amyloid-β (Aβ) is commonly recognized as the most important factor that results in neuronal cell death and accelerates the progression of Alzheimer’s disease (AD). Increasing evidence suggests that microglia activated by Aβ release an amount of neurotoxic inflammatory cytokines that contribute to neuron death and aggravate AD pathology. In our previous studies, we found that lychee seed fraction (LSF), an active fraction derived from the lychee seed, could significantly improve the cognitive function of AD rats and inhibit Aβ-induced neuroinflammation in vitro, and decrease neuronal injuries in vivo and in vitro. In the current study, we aimed to isolate and identify the specific components in LSF that were responsible for the anti-neuroinflammation effect using preparative high performance liquid chromatography (pre-HPLC), liquid chromatography-mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR) methods. To this end, we confirmed two polyphenols including catechin and procyanidin A2 that could improve the morphological status of BV-2 cells and suppress the release, mRNA levels, and protein expression of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) through downregulating the nuclear factor-κB (NF-κB) signaling pathway using ELISA, RT-PCR, and Western blotting methods. Furthermore, catechin and procyanidin A2 could inhibit Aβ-induced apoptosis in BV-2 cells by upregulating Bcl-2 and downregulating Bax protein expression. Therefore, the current study illustrated the active substances in lychee seed, and first reported that catechin and procyanidin A2 could suppress neuroinflammation in Aβ-induced BV-2 cells, which provides detailed insights into the molecular mechanism of catechin and procyanidin A2 in the neuroprotective effect, and their further validations of anti-neuroinflammation in vivo is also essential in future research.
    Type of Medium: Online Resource
    ISSN: 1422-0067
    URL: Article
    DOI: 10.3390/ijms19072109
    Language: English
    Publisher: MDPI AG
    Publication Date: 2018
    detail.hit.zdb_id: 2019364-6
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    E-Region Field-Aligned Irregularities in the Middle of a Solar Eclipse Observed by a Bistatic Radar
    MDPI AG ; 2022
    In:  Remote Sensing Vol. 14, No. 2 ( 2022-01-15), p. 392-
    Details
    In: Remote Sensing, MDPI AG, Vol. 14, No. 2 ( 2022-01-15), p. 392-
    Abstract: The Wuhan Ionospheric Oblique Backscatter Sounding System (WIOBSS) was applied as a bistatic radar to record the ionospheric E-region responses to a solar eclipse on 22 July 2009. The transmitter was located in Wuhan and the receiver was located in Huaian. The receiver observed anomalous echoes with larger Doppler shifts at the farther ranges compared with the echoes reflected by Es. According to the simulated ray propagation paths of the reflected and scattered waves, we considered that the anomalous echoes were scattered by E-region field-aligned irregularities (FAIs). The locations of the FAIs recorded by the WIOBSS were estimated with the International Geomagnetic Reference Field (IGRF) and the observed propagation parameters. These irregularities occurred at around the eclipse maximum and lasted for ~20–40 min. The steep plasma density gradient induced by the fast drop photo ionization under the lunar shadow was beneficial to the occurrence of gradient drift instability to generate the FAIs. They were different from the gravity wave-induced irregularities occurring in the recovery phase of the solar eclipse.
    Type of Medium: Online Resource
    ISSN: 2072-4292
    URL: Article
    DOI: 10.3390/rs14020392
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2513863-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Hybrid Beamforming for MISO System via Convolutional Neural Network
    MDPI AG ; 2022
    In:  Electronics Vol. 11, No. 14 ( 2022-07-15), p. 2213-
    Details
    In: Electronics, MDPI AG, Vol. 11, No. 14 ( 2022-07-15), p. 2213-
    Abstract: Hybrid beamforming (HBF) is a promising approach to obtain a better balance between hardware complexity and system performance in massive MIMO communication systems. However, the HBF optimization problem is a challenging task due to its nonconvex property in terms of design complexity and spectral efficiency (SE) performance. In this work, a low-complexity convolutional neural network (CNN)-based HBF algorithm is proposed to solve the SE maximization problem under the constant modulus constraint and transmit power constraint in a multiple-input single-output (MISO) system. The proposed CNN framework uses multiple convolutional blocks to extract more channel features. Considering that the solutions for the HBF are hard to obtain, we derive an unsupervised learning mechanism to avoid any labeled data when training the constructed CNN. We discuss the performance of the proposed algorithm in terms of both the generalization ability for multiple CSIs and the specific solving ability for an individual CSI, respectively. Simulations show its advantages in both SE and complexity over other related algorithms.
    Type of Medium: Online Resource
    ISSN: 2079-9292
    URL: Article
    DOI: 10.3390/electronics11142213
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2662127-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Detection of CO2 and CH4 Concentrations on a Beijing Urban Road Using Vehicle-Mounted Tunable Diode Laser Absorption Spectroscopy
    MDPI AG ; 2023
    In:  Photonics Vol. 10, No. 8 ( 2023-08-17), p. 938-
    Details
    In: Photonics, MDPI AG, Vol. 10, No. 8 ( 2023-08-17), p. 938-
    Abstract: The analysis of greenhouse gas emission characteristics on urban roads is of great significance for understanding the sources and sinks of urban greenhouse gases and their changing patterns. Based on tunable diode laser derivative absorption spectroscopy technology, which features high resolution, high sensitivity, and fast response, a vehicle-mounted system capable of simultaneously detecting CO2 and CH4 has been developed. The system has a response time of 0.38 s, with detection sensitivities of 5 ppb for CH4 and 0.2 ppm for CO2, power consumption of approximately 4.8 W, a weight of less than 3 kg, and dimensions of 255 mm × 275 mm × 85 mm. Using this system, monitoring campaigns were conducted on the same road in Beijing, running north–south, during different time periods in April and June 2023. The results show that there is little correlation between changes in CO2 and CH4 concentrations on the road, and these gas concentrations exhibit different influencing factors and spatiotemporal characteristics. The CO2 concentration on the road is primarily related to the degree of traffic congestion and does not exhibit significant seasonal variations. The average CO2 concentration measured on the road is much higher than the global average CO2 concentration during the same period. On the other hand, the CH4 concentration on the road is not strongly correlated with traffic congestion but is closely related to the leakage of methane from specific emission wells or covers. The CH4 concentration is higher in the morning, gradually decreases as the sun rises, and then increases again after sunset. The CH4 concentration measured at night in June is significantly lower than that in April, reflecting some seasonal variation. The CH4 concentration on the Beijing urban road is slightly higher than the global average CH4 concentration during the same period. The vehicle-mounted experiments verified the feasibility of using this self-developed system for vehicle-mounted detection of greenhouse gas concentrations on urban roads. The research results can provide data for analyzing the spatial pattern of regional carbon sources and sinks.
    Type of Medium: Online Resource
    ISSN: 2304-6732
    URL: Article
    DOI: 10.3390/photonics10080938
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2770002-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Nonlinear Relationship Between the Yield of Solar-Induced Chlorophyll Fluorescence and Photosynthetic Efficiency in Senescent Crops
    MDPI AG ; 2020
    In:  Remote Sensing Vol. 12, No. 9 ( 2020-05-09), p. 1518-
    Details
    In: Remote Sensing, MDPI AG, Vol. 12, No. 9 ( 2020-05-09), p. 1518-
    Abstract: It has been demonstrated that solar-induced chlorophyll fluorescence (SIF) is linearly related to the primary production of photosynthesis (GPP) in various ecosystems. However, it is unknown whether such linear relationships have been established in senescent crops. SIF and GPP can be expressed as the products of absorbed photosynthetically active radiation (APAR) with the SIF yield and photosystem II (PSII) operating efficiency, respectively. Thus, the relationship between SIF and GPP can be represented by the relationship between the SIF yield and PSII operating efficiency when the APAR has the same value. Therefore, we analyzed the relationship between the SIF yield and the PSII operating efficiency to address the abovementioned question. Here, diurnal measurements of the canopy SIF (760 nm, F760) of soybean and sweet potato were manually measured and used to calculate the SIF yield. The PSII operating efficiency was calculated from measurements of the chlorophyll fluorescence at the leaf level using the FluorImager chlorophyll fluorescence imaging system. Meanwhile, field measurements of the gas exchange and other physiological parameters were also performed using commercial-grade devices. The results showed that the SIF yield was not linearly related to the PSII operating efficiency at the diurnal scale, reflecting the nonlinear relationship between SIF and GPP. This nonlinear relationship mainly resulted from the heterogeneity and diurnal dynamics of the PSII operating efficiency and from the intrinsic diurnal changes in the maximum efficiency of the PSII photochemistry and the proportion of opened PSII centers. Intensifying respiration was another factor that complicated the response of photosynthesis to the variation in environmental conditions and negatively impacted the relationship between the SIF yield and the PSII operating efficiency. The nonlinear relationship between the SIF yield and PSII efficiency might yield errors in the estimation of GPP using the SIF measurements of senescent crops.
    Type of Medium: Online Resource
    ISSN: 2072-4292
    URL: Article
    DOI: 10.3390/rs12091518
    Language: English
    Publisher: MDPI AG
    Publication Date: 2020
    detail.hit.zdb_id: 2513863-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...