Search Results (765)

Resistance to cytarabine (Ara-C) remains a major obstacle to the successful treatment of acute myeloid leukemia (AML). Therefore, modulating Ara-C resistance is indispensable for improving clinical outcomes. We previously demonstrated that sodium caseinate (SC), a salt derived from casein, the principal milk protein, inhibits proliferation and modulates the expression of Ara-C resistance-related genes in chemoresistant cells. However, it remains unclear whether the combination of SC with antineoplastic agents enhances apoptosis, modulates chemoresistance-related genes, and prolongs the survival of tumor-bearing mice implanted with chemoresistant cells. Here, we investigated the effects of SC in combination with Ara-C or daunorubicin (DNR) on cell proliferation, apoptosis, the expression of chemoresistance-associated genes, and the survival of tumor-bearing mice. Crystal violet assays, quantitative reverse transcription polymerase chain reaction (qRT-PCR), immunofluorescence, flow cytometry, and Kaplan–Meier survival curves were used to evaluate the effects of combinations in chemoresistant cells. We demonstrate that the IC₂₅ concentration of SC, when combined with antileukemic agents, increases the sensitivity of chemoresistant WEHI-CR50 cells to Ara-C by downregulating SIRT1 and MDR1, upregulating the expression of ENT1 and dCK, enhancing apoptosis, and prolonging the survival of WEHI-CR50 tumor-bearing mice. Our data suggest that SC in combination with antileukemic agents could be an effective adjuvant for Ara-C-resistant AML. Full article

Background/Objectives: Humulus lupulus (hops) are a perennial, dioecious plant widely cultivated for beer production, used for their distinguishing aroma and bitterness—traits that confer high added value status. Various hop-derived compounds have been reported to exhibit antioxidant, antimicrobial, antiproliferative and other bioactive effects. This systematic review and meta-analysis assesses the impact of hop compounds on the viability of diverse cancer cell lines. Methods: A comprehensive literature search was performed following PRISMA guidelines. Data were synthesized via multivariate meta-analysis and meta-regression, using IC₅₀ values as the effect size. Key variables included assay type (SRB, tetrazolium salt-based, crystal violet), exposure duration (24, 48, 72 h), specific hop compound and cancer cell line. Results: Of 622 articles identified, 61 met eligibility criteria, yielding 354 individual experiments. Meta-regression of xanthohumol (XN) IC₅₀ values across SRB, tetrazolium and crystal violet assays revealed no statistically significant differences at 24 h (p = 0.77), 48 h (p = 0.35) and 72 h (p = 0.70), supporting the interchangeability of the methods. Meta-analysis confirmed that hop constituents inhibit cancer cell proliferation; XN emerged as the most potent flavonoid (IC₅₀ = 16.89 μM at 72 h), while lupulone was the strongest compound overall (IC₅₀ = 5.00 μM at 72 h). Crude hop extracts demonstrated greater antiproliferative selectivity for cancer versus non-cancer cells (IC₅₀ = 35.23 vs. 43.80 μg/mL at 72 h). Conclusions: Hop compounds, and particularly bitter acids, demonstrate promising antiproliferative activity against cancer cells with comparatively low toxicity to healthy cells. Furthermore, our analysis confirms the comparability of SRB, tetrazolium-based and crystal violet assays, supporting the robust integration of antiproliferative data. Full article

The article is focused on the quantitative assessment of the thermal impact of polar mesospheric clouds (PMCs) on the mesopause caused by the emission of absorbed solar and terrestrial infrared (IR) radiation by cloud particles. For this purpose, a parameterization of mesopause heating by PMC crystals has been developed, the main feature of which is to incorporate the thermal properties of ice and the interaction of cloud particles with the environment. Parametrization is based on PMCs zero-dimensional (0-D) model and uses temperature, pressure, and water vapor data in the 80–90 km altitude range retrieved from Solar Occultation for Ice Experiment (SOFIE) measurements. The calculations are made for 14 PMC seasons in both hemispheres with the summer solstice as the central date. The obtained results show that PMCs can make a significant contribution to the heat balance of the upper atmosphere, comparable to the heating caused, for example, by the dissipation of atmospheric gravity waves (GWs). The interhemispheric differences in heating are manifested mainly in the altitude structure: in the Southern Hemisphere (SH), the area of maximum heating values is 1–2 km higher than in the Northern Hemisphere (NH), while quantitatively they are of the same order. The most intensive heating is observed at the lower boundary of the minimum temperature layer (below 150 K) and gradually weakens with altitude. The NH heating median value is 5.86 K/day, while in the SH it is 5.24 K/day. The lowest values of heating are located above the maximum of cloud ice concentration in both hemispheres. The calculated heating rates are also examined in the context of the various factors of temperature variation in the observed atmospheric layers. It is shown in particular that the thermal impact of PMC is commensurate with the influence of dissipating gravity waves at heights of the mesosphere and lower thermosphere (MLT), which parameterizations are included in all modern numerical models of atmospheric circulation. Hence, the developed parameterization can be used in global atmospheric circulation models for further study of the peculiarities of the thermodynamic regime of the MLT. Full article

In this article, an efficient and straightforward protocol for the construction of complex dispirocyclic skeletons via regioselective intramolecular Michael addition is presented. Diverse dispirocyclic compounds were synthesized under mild and transition-metal-free conditions with good to excellent yields. Most stereoisomers were conveniently separated by column chromatography, and their relative configurations were identified by single-crystal X-Ray diffraction of representative compounds. A scale-up experiment validated the practicality of this method. In an in vitro assay, some dispirocyclic compounds exhibited potent cytotoxicity with an IC₅₀ value of 10⁻⁶ mol/L. Full article

Semen cryopreservation is associated with sperm vulnerability to oxidative stress and ice crystal-induced damage, adversely affecting in vitro fertilization (IVF) success. This study aimed to investigate the effects of freezing diluent supplemented with antioxidant limonin (Lim), myo-inositol (MYO), and the ice crystal formation inhibitor L-proline (LP) through sperm motility, morphological integrity, and antioxidant capacity. The Lim (150 mM), MYO (90 mM), and LP (100 mM) significantly ameliorated the quality of post-thaw sperm in Debao boar, and combined treatment of these agents significantly enhanced sperm motility, structural integrity, and antioxidant capacity compared with individual agents (p < 0.05). Notably, the combined use of these agents reduced glycerol concentration in the freezing diluent from 3% to 2%. Meanwhile, the integrity of the sperm plasma membrane, acrosome membrane, and mitochondrial membrane potential was significantly improved (p < 0.05), and the result of IVF revealed the total cell count of the blastocysts was also greater in the 2% glycerol group (p < 0.05). In conclusion, the newly developed freezing diluent for semen, by adding Lim (150 mM), MYO (90 mM), and LP (100 mM), can enhance the quality of frozen–thawed Debao boar sperm and reduce the concentration of glycerol from 3% to 2% as high concentrations of glycerol can impair the quality of thawed sperm and affect in vitro fertilization outcomes. In conclusion, the improved dilution solution formulated demonstrated efficacy in enhancing the quality of porcine spermatozoa following cryopreservation and subsequent thawing. Full article

Combining biosynthetic gene cluster analysis with the OSMAC strategy, fractionation of the fermentation extract of Aspergillus templicola from the sponge Agelas sp. led to the isolation of four novel cytochalasins, colachalasins J–M (1–4), a novel cyclic pentapeptide, avellanin P (5), together with five known compounds (6–10). The structures of 1–9 were elucidated using spectroscopic data, single crystal X-ray diffraction, and Marfey’s analysis. Compound 2 exhibited potent anti-inflammatory activity in zebrafish assays. Additionally, Compounds 4 and 6 showed modest cytotoxicity against several human cancer cell lines with IC₅₀ values ranging from 2.6 to 11.2 μm. Full article

The aim of this study was to evaluate the effect of the iota, kappa and lambda carrageenan fractions on the physical properties and crystal structure of a fruit sorbet prepared from frozen mango fruits. During this study, physical properties such as density, cryoscopic temperature, osmotic pressure, overrun and melting time were analyzed. In order to assess the crystal structure and its changes, microscope images were taken of each sample after 1, 30 and 90 days of storage. The stabilizers showed no significant effect on the physical properties of the ice cream mixture; however, the sample with iota carrageenan stood out for having the highest overrun (58.7%) and the sample with kappa carrageenan took the longest to melt of all tested samples (almost 21 min). This study shows a significant effect of carrageenans in reducing the initial size of ice crystals as well as reducing recrystallization during storage. The stabilizing blend using ι-carrageenan provided the most effective cryoprotective properties, with an ice crystal diameter of 9 µm. Full article

The emergence of antimicrobial resistance and the increasing demand for a healthier lifestyle have set new goals for science and industry. In the search for new, more effective, and environmentally friendly antimicrobial agents, special attention is being paid to natural resources. In this regard, essential oils derived from plants, which are widely used in the cosmetic, food, and pharmaceutical industries, are one of the solutions. In view of the above, this study aims to investigate the biological effects of Abies alba essential oil (AAEO). The chemical profile of AAEO was evaluated by GC/MS analysis, which revealed a high abundance of limonene (52.2%) and α-pinene (36.2%). Antioxidant activity evaluation showed a higher potential of AAEO in scavenging ABTS radical species with an IC₅₀ value of 1.18 ± 0.05 mg/mL. In vitro antimicrobial activity was determined by disc diffusion and minimum inhibitory concentration assays and showed that AAEO was more efficient in inhibiting the growth of G⁺ bacterial species. On contrary, in situ evaluations of antimicrobial effects of AAEO on different food models (strawberry, kiwi, white radish, and beetroot) resulted in more efficient suppression of G⁻ bacterial species. Although AAEO showed low effects on yeasts determined by in vitro methods, in situ investigations showed its higher potential in eradication of Candida yeast. The antibiofilm properties of the AAEO matrix were determined by means of crystal violet assay and MALDI-TOF MS Biotyper analysis against biofilm-forming Salmonella enterica. The analysis performed led to the conclusion that AAEO, when applied prior to biofilm formation, may contribute to the removal of planktonic cells and alter the abiotic surface, thereby reducing the suitability of Salmonella enterica for microbial attachment. Full article

Fresh-cut potato slices are prone to browning. Although freezing is an effective method of preserving food, freezing and thawing cause inevitable damage to potato tissues. This study explored the freeze-protective effects of trehalose and sorbitol under atmospheric pressure impregnation and vacuum impregnation by analyzing their influences on the cell structural and textural characteristics of frozen–thawed potato slices. The results showed that both trehalose and sorbitol can significantly improve the quality of frozen–thawed potato slices. Vacuum impregnation resulted in a higher total sugar content in the impregnated potato slices than atmospheric pressure impregnation (p < 0.05). Sorbitol impregnation significantly reduced cell damage and nutrient loss of frozen–thawed potato slices; specifically, under vacuum impregnation conditions, the juice loss rate and relative electrical conductivity decreased to 7.58 ± 0.47% and 32.90 ± 1.83 mS/cm, respectively. Texture analysis showed that sorbitol impregnation resulted in significantly higher puncture hardness and TPA hardness in frozen–thawed potato slices than trehalose impregnation. Furthermore, observations of cell activity and transmission electron microscopy of potato tissues verified sorbitol’s advantages in maintaining cell structure integrity and reducing ice crystal damage. Hence, sorbitol vacuum impregnation is highly recommended as a pretreatment in potato quick freezing processes. This study provides a theoretical basis and technical support for the improvement of the quality of quick-frozen potato products, and for the later processing and manufacturing of frozen potato slices. Full article

The formation and evolution of ice in the Yellow River represent complex dynamic processes. To elucidate the structural characteristics of ice crystals and their governing mechanisms in the Inner Mongolia reach, this investigation utilized high-resolution Sentinel-2 satellite imagery to systematically monitor spatiotemporal variations in open-water formations across diverse channel morphologies throughout the ice regime period. Systematic ice sampling was conducted across diverse channel morphologies of the Yellow River to quantify critical parameters, including crystalline structure characteristics, equivalent diameter distributions, density variations, and sediment content profiles. The results indicate the transformation of open water resulting from various river configurations during the freezing season exhibits distinct characteristics, which are significantly influenced by temperature variations. Ice crystal characterization exhibits that the crystalline structure predominantly manifests as two primary forms: columnar and granular ice formations, with their distribution varying systematically across different channel configurations. Ice crystal morphology exhibits heterogeneity in both form and dimensional characteristics. Columnar ice consistently exhibits larger equivalent diameters compared to granular ice formations. A progressive enhancement in the equivalent diameter of crystals is observed along the vertical axis corresponding to the thickness of the ice during the growth process. The ranges of variation in ice crystal size, ice density, and mud content within ice exhibit differences contingent upon the specific crystal structures present. Observational studies and comparative analyses of ice samples from the Inner Mongolia reach of the Yellow River reveal that channel morphology, ambient thermal conditions, and hydrodynamic parameters are the primary determinants governing the variability in ice microstructure and its associated physical characteristics. This investigation provides fundamental scientific insights and quantitative data that advance our understanding of river ice microstructural characteristics. Full article

A quinoline unit is present in many natural products and is an attractive pharmacophore for the development of clinical drugs, including antineoplastics. The title compound (QN) was synthesized via the condensation reaction between quinoline-2-carboxaldehyde and 2-nitrobenzhydrazide. QN’s structure was examined by X-ray diffraction and features extensive stacking interactions in the crystal. The compound is weakly toxic to HepG2 cells, with an IC₅₀ exceeding 400 μM for 48 h exposure. QN at 50 μM, with the dose reduction index in the range of 1.9–4.4, potentiated the cytotoxicity of several clinical chemotherapeutic drugs, including doxorubicin and other topoisomerase inhibitors, vincristine, and carboplatin, but not cisplatin or 5-fluorouracil. The calculated ADME parameters predict satisfactory drug-like properties for QN. Full article

Prefabricated components inevitably generate numerous assembly joints during installation, with each 1 mm increase in joint width correlating to a 15–20% elevation in the annual occurrence frequency of the frost formation risk. In the Inner Mongolia Region, the water migration at wall connection interfaces during winter significantly exacerbates freeze–thaw damage due to persistent thermal gradients. A coupled heat–moisture transfer model incorporating gas–liquid–solid phase transitions was developed, with the liquid moisture content and temperature gradient as dual driving forces. A validation against internationally recognized BS EN 15026:2007 benchmark cases confirmed the model robustness. The prefabricated sandwich insulation walls reconstructed with region-specific volcanic ash materials underwent a comparative evaluation of temperature and relative humidity distributions under varied winter conditions. Furthermore, we analyze and assess the potential for freezing at connection points and identify the specific areas at risk. Synergistic effects between assembly gaps and indoor–outdoor environmental interactions on wall performance degradation were systematically assessed. The results indicated that, across all working conditions, both the temperature and relative humidity at each wall measurement point underwent periodic variations influenced by the outdoor environment. These fluctuations decreased in amplitude from the exterior to the interior, accompanied by a noticeable delay effect. Specifically, at Section 2, the wall temperatures at points B2–B8 were higher compared to those at A2–A8 of Section 1. The relative humidity gradient remained relatively stable at each measurement point, while the temperature fluctuation amplitude was smaller by 2.58 ± 0.3 °C compared to Section 1. Under subfreezing conditions, Section 1 demonstrates a marked reduction in relative humidity (Cases 1-3 and 2-3) compared to reference cases, which is indicative of internal ice crystallization. Conversely, Section 2 maintains higher relative humidity values under identical therma. These findings suggest that prefabricated building joints significantly impact indoor and outdoor wall temperatures, potentially increasing the indoor heat loss and accelerating temperature transfer during winter. Full article

Improving the texture and shelf-life of whey-based ice cream remains a key challenge in clean-label food formulation. This study investigated the effects of different stabilizing ingredients—including Cremodan SI 320 (0.6%), oat β-glucan (0.25–0.5%), and yeast β-glucan (0.25–0.5%)—on the physicochemical properties and freezing dynamics of ice cream made from liquid hydrolyzed demineralized whey concentrate. Compared to Cremodan, oat β-glucan significantly lowered the freezing point, improved overrun, and enhanced melting resistance. Yeast β-glucan led to the smallest initial ice crystals (8.49 ± 0.37 μm) and minimal growth after one month (9.52 ± 0.16 μm), outperforming the control and Cremodan samples in crystal stability. The chemical composition and textural properties of each formulation were also evaluated. These findings demonstrate that oat and yeast β-glucans function as natural stabilizers, offering clean-label potential and improved structural integrity in frozen dairy desserts. Full article

Drying constitutes an essential step in aerogel fabrication, where the drying method directly determines the pore structure and consequently influences the material’s functionality. This study employed various drying techniques to prepare balsa-wood-derived aerogels, systematically investigating their effects on microstructure, density, and performance characteristics. The results demonstrate that different drying methods regulate aerogels through distinct pore structure modifications. Supercritical CO₂ drying optimally preserves the native wood microstructure, yielding aerogels with superior thermal insulation performance. Freeze-drying induces the formation of ice crystals, which reconstructs the microstructure, resulting in aerogels with minimal density, significantly enhanced permeability, and exceptional cyclic water absorption capacity. Vacuum drying, oven drying, and natural drying all lead to significant deformation of the aerogel pore structure. Among them, oven drying increases the pore quantity of aerogels through volumetric contraction, thereby achieving the highest specific surface area. However, aerogels prepared by air drying have the highest density and the poorest thermal insulation performance. This study demonstrates that precise control of liquid surface tension during drying can effectively regulate both the pore architecture and functional performance of wood-derived aerogels. The findings offer fundamental insights into tailoring aerogel properties through optimized drying processes, providing valuable guidance for material design and application development. Full article

Freezing has been widely used to preserve the freshness and quality of crayfish (Procambarus clarkii). However, temperature fluctuations during transportation and storage inevitably affect the quality attributes of crayfish. In this study, the effect of liquid nitrogen freezing (LNF) on crayfish myofibrillar protein (MP) was investigated under freeze–thaw (FT) cycles. The small ice crystals formed by LNF could reduce the conversion of sulfhydryl groups to disulfide bonds, preventing the exposure of hydrophobic groups, thereby maintaining the functional properties of MP. LNF could prevent the degradation and oxidation of MP and maintain its compact and smooth microstructure. Compared to refrigerator freezing (RF), LNF showed a stronger protective effect on the secondary and tertiary structures of MP, alleviating their conformational changes. Therefore, LNF could be an alternative freezing method to preserve crayfish quality against FT cycles during transportation and storage. Full article