Circular RNAs (circRNAs) can participate in multiple cancers, including breast cancer. Increasing circRNAs are recognized in various cancers because of the high‐throughput sequencing. However, the ...potential physiological effect of hsa_circ_0136666 in breast cancer progression is unknown. In our study, the biological role of hsa_circ_0136666 in breast cancer development was studied. It was displayed that hsa_circ_0136666 was greatly increased in breast cancer. In addition, overexpression of hsa_circ_0136666 was able to promote Michigan Cancer Foundation‐7 (MCF7) and BT474 cell proliferation and triggered cell cycle in G2/M phase. microRNA plays critical role in tumor development and they can act as direct targets of circRNAs. miR‐1299 has been implicated as a famous tumor suppressor in many cancers. Here, miR‐1299 was predicted as the target of hsa_circ_0136666. Meanwhile, its Upregulation repressed breast cancer proliferation, migration and invasion capacity, which could be reversed by the increase of hsa_circ_0136666. Furthermore, Cyclin‐dependent kinase 6 (CDK6) was speculated as the downstream target of miR‐1299. In MCF7 and BT474 cells, CDK6 was greatly overexpressed and it was shown that CDK6 contributed a lot to breast cancer progression. Subsequently, it was implied that hsa_circ_0136666 could modulate CDK6 levels positively in vitro. In conclusion, it was revealed that Upregulation of hsa_circ_0136666 promoted breast cancer progression by sponging miR‐1299 and targeting CDK6.
We predicted cyclin‐dependent kinase 6 (CDK6) as the target of miR‐1299 using bioinformatics analysis. The association between them was proved in our research and miR‐1299 inhibitors increased the expression of CDK6, and it was exhibited that overexpression of CDK6 was able to induce breast cancer progression and hsa_circ_0136666 modulated its expression positively. Taken these together, our data implied that hsa_circ_0136666/miR‐1299/CDK6 axis was involved in breast cancer and hsa_circ_0136666 might act as a biomarker for breast cancer treatment.
We explored whether medical health workers had more psychosocial problems than nonmedical health workers during the COVID-19 outbreak.
An online survey was run from February 19 to March 6, 2020; a ...total of 2,182 Chinese subjects participated. Mental health variables were assessed via the Insomnia Severity Index (ISI), the Symptom Check List-revised (SCL-90-R), and the Patient Health Questionnaire-4 (PHQ-4), which included a 2-item anxiety scale and a 2-item depression scale (PHQ-2).
Compared with nonmedical health workers (n = 1,255), medical health workers (n = 927) had a higher prevalence of insomnia (38.4 vs. 30.5%, p < 0.01), anxiety (13.0 vs. 8.5%, p < 0.01), depression (12.2 vs. 9.5%; p< 0.04), somatization (1.6 vs. 0.4%; p < 0.01), and obsessive-compulsive symptoms (5.3 vs. 2.2%; p < 0.01). They also had higher total scores of ISI, GAD-2, PHQ-2, and SCL-90-R obsessive-compulsive symptoms (p ≤ 0.01). Among medical health workers, having organic disease was an independent factor for insomnia, anxiety, depression, somatization, and obsessive-compulsive symptoms (p < 0.05 or 0.01). Living in rural areas, being female, and being at risk of contact with COVID-19 patients were the most common risk factors for insomnia, anxiety, obsessive-compulsive symptoms, and depression (p < 0.01 or 0.05). Among nonmedical health workers, having organic disease was a risk factor for insomnia, depression, and obsessive-compulsive symptoms (p < 0.01 or 0.05).
During the COVID-19 outbreak, medical health workers had psychosocial problems and risk factors for developing them. They were in need of attention and recovery programs.
Four polysaccharide fractions (P‐1: 71.40%, P‐2: 1.95%, P‐3: 1.14%, P‐4: 1.64%) were isolated from crude Polygonatum sibiricum polysaccharide (PSP), processed by water extraction, ethanol ...precipitation, and further separated with diethylaminoethyl cellulose‐52 anion‐exchange chromatography. Their molecular weights and monosaccharide compositions were characterized by high performance gel chromatography with evaporative light scattering detector and ultraviolet–visible detector. The antioxidant activity of four polysaccharides fractions were assessed by the electron transfer menchanism (DPPH, ferric reducing power, and ABST assays) and chelation of transition metals (Fe2+ and Cu2+ chelation ability). The highest content fraction P‐1 exhibited the lowest antioxidant activity, and the ranking of antioxidant capacity was P‐4 > P‐3 > P‐2 > PSP > P‐1. After processed by microwave‐assisted degradation, the molecular weight of P‐1 was decreased from 2.99 × 105 to 2.33 × 103 Da, while the antioxidant activity of degraded P‐1 was about eightfold higher than natural P‐1. These results indicated that the proposed microwave‐assisted degradation approach was an efficacious methodology to improve their bioactivity by lower the molecular weight of polysaccharides.
Practical Application
This study provided an environmentally friendly, convenient and efficient microwave‐assisted degradation technology to process the neutral polysaccharides from Polygonatum sibiricum. The results could be used for the development and utilization of various plant polysaccharides as a kind of food supplement in our daily life.
•The temperature in the three basins increased significantly with a staircase form.•The significant increase of temperature mainly occurred in autumn and winter.•The precipitation exhibited distinct ...interannual variations and regional differences.•Interannual variations of precipitation were associated with ENSO SST variability.•Decadal variations of precipitation were associated with QDO-like SST patterns.
The variation characteristics of precipitation and temperature in the three major Chinese river basins (Yellow River, Yangtze River and Pearl River) in the period of 1957–2013 were analyzed on an annual and seasonal basis, as well as their links to sea surface temperature (SST) variations in the tropical Pacific and Indian Ocean on both interannual and decadal time scales. Annual mean temperature of the three river basins increased significantly overall since 1957, with an average warming rate of about 0.19°C/10a, but the warming was characterized by a staircase form with steps around 1987 and 1998. The significant increase of annual mean temperature could mostly be attributed to the remarkable warming trend in spring, autumn and winter. Warming rates in the northern basins were generally much higher than in the southern basins. However, both the annual precipitation and seasonal mean precipitation of the three river basins showed little change in the study area average, but distinct interannual variations since 1957 and clear regional differences. An overall warming–wetting tendency was found in the northwestern and southeastern river basins in 1957–2013, while the central regions tended to become warmer and drier.
Results from a Maximum Covariance Analysis (MCA) showed that the interannual variations of seasonal mean precipitation and surface air temperature over the three river basins were both associated with the El Niño-Southern Oscillation (ENSO) since 1957. ENSO SST patterns affected precipitation and surface air temperature variability throughout the year, but with very different response patterns in the different seasons. For instance, temperature in most of the river basins was positively correlated with central-eastern equatorial Pacific SST in winter and spring, but negatively correlated in summer and autumn. On the decadal time scale, the seasonal mean precipitation and surface air temperature variations were strongly associated with the Pacific Quasi-Decadal Oscillation.
Threshold switching (TS) devices are promising candidates to build highly compact and energy efficient artificial neurons. Here, we present a Pt/Ag/TiN/HfAlO x /Pt (PATHP) device with excellent TS ...characteristics, including a large selectivity(10 10 ), a wide range of operation current from 10 nA to 1 mA, an extremely steep slope (0.63 mV/dec) and fast turn-on speed (50 ns). The stable TS performance can be ascribed to the introduction of TiN buffer layer and the alternate atomic layer deposited HfAlOx layer. Further, we experimentally demonstrate the functions of leaky-integrate-and-fire neurons with low power feature based on a RC circuit and a single device, respectively, which are essential for constructing spiking neuromorphic systems.
Despite their ubiquitous distribution and significant ecological roles, soil microorganisms have long been neglected in investigations addressing parasitic plant–host interactions. Because nutrient ...deprivation is a primary cause of host damage by parasitic plants, we hypothesized that beneficial soil microorganisms conferring nutrient benefits to parasitized hosts may play important roles in alleviating damage.
We conducted a pot cultivation experiment to test the inoculation effect of an arbuscular mycorrhizal fungus (Glomus mosseae), a rhizobium (Rhizobium leguminosarum) and their interactive effects, on alleviation of damage to a legume host (Trifolium repens) by two root hemiparasitic plants with different nutrient requirements (N-demanding Pedicularis rex and P-demanding P. tricolor).
Strong interactive effects between inoculation regimes and hemiparasite identity were observed. The relative benefits of microbial inoculation were related to hemiparasite nutrient requirements. Dual inoculation with the rhizobium strongly enhanced promotional arbuscular mycorrhizal effects on hosts parasitized by P. rex, but reduced the arbuscular mycorrhizal promotion on hosts parasitized by P. tricolor.
Our results demonstrate substantial contribution of arbuscular mycorrhizal and rhizobial symbioses to alleviating damage to the legume host by root hemiparasites, and suggest that soil microorganisms are critical factors regulating host–parasite interactions and should be taken into account in future studies.
The development of bone‐rebuilding anabolic agents for potential use in the treatment of bone loss conditions, such as osteoporosis, has been a long‐standing goal. Genetic studies in humans and mice ...have shown that the secreted protein sclerostin is a key negative regulator of bone formation, although the magnitude and extent of sclerostin's role in the control of bone formation in the aging skeleton is still unclear. To study this unexplored area of sclerostin biology and to assess the pharmacologic effects of sclerostin inhibition, we used a cell culture model of bone formation to identify a sclerostin neutralizing monoclonal antibody (Scl‐AbII) for testing in an aged ovariectomized rat model of postmenopausal osteoporosis. Six‐month‐old female rats were ovariectomized and left untreated for 1 yr to allow for significant estrogen deficiency‐induced bone loss, at which point Scl‐AbII was administered for 5 wk. Scl‐AbII treatment in these animals had robust anabolic effects, with marked increases in bone formation on trabecular, periosteal, endocortical, and intracortical surfaces. This not only resulted in complete reversal, at several skeletal sites, of the 1 yr of estrogen deficiency‐induced bone loss, but also further increased bone mass and bone strength to levels greater than those found in non‐ovariectomized control rats. Taken together, these preclinical results establish sclerostin's role as a pivotal negative regulator of bone formation in the aging skeleton and, furthermore, suggest that antibody‐mediated inhibition of sclerostin represents a promising new therapeutic approach for the anabolic treatment of bone‐related disorders, such as postmenopausal osteoporosis.
The current lithospheric root of the South China Block has been partly removed, yet what mechanisms modified the lithospheric structure remain highly controversial. Here we use a new joint seismic ...inversion algorithm to image tabular high-velocity anomalies at depths of ~90-150 km in the asthenosphere beneath the convergent belt between the Yangtze and Cathaysia blocks that remain weakly connected with the stable Yangtze lithosphere. Based on obtained seismic images and available geochemical data, we interpret these detached fast anomalies as partially destabilized lower lithosphere that initially delaminated at 180-170 Ma and has relaminated to their original position after warming up in the mantle by now. We conclude that delamination is the most plausible mechanism for the lithospheric modification and the formation of a Mesozoic Basin and Range-style magmatic province in South China by triggering adiabatic upwelling of the asthenosphere and consequent lithospheric extension and extensive melting of the overlying crust.
We studied the mechanism of the significant enhancement in the enzymatic saccharification of lignocelluloses at an elevated pH of 5.5–6.0. Four lignin residues with different sulfonic acid contents ...were isolated from enzymatic hydrolysis of lodgepole pine pretreated by either dilute acid (DA) or sulfite pretreatment to overcome recalcitrance of lignocelluloses (SPORL). The adsorption isotherms of a commercial Trichoderma reesi cellulase cocktail (CTec2) produced by these lignin residues at 50 °C were measured in the pH range of 4.5–6.0. The zeta potentials of these lignin samples were also measured. We discovered that an elevated pH significantly increased the lignin surface charge (negative), which causes lignin to become more hydrophilic and reduces its coordination affinity to cellulase and, consequently, the nonspecific binding of cellulase. The decreased nonspecific cellulase binding to lignin is also attributed to enhanced electrostatic interactions at elevated pH through the increased negative charges of cellulase enzymes with low pI. The results validate the hypothesis that the increases in enzymatic saccharification efficiencies at elevated pH for different pretreated lignocelluloses are solely the result of decreased nonspecific cellulase binding to lignin. This study contradicts the well‐established concept that the optimal pH is 4.8–5.0 for enzymatic hydrolysis using Trichoderma reesi cellulose, which is widely accepted and exclusively practiced in numerous laboratories throughout the world. Because an elevated pH can be easily implemented commercially without capital cost and with minimal operating cost, this study has both scientific importance and practical significance.
Phenomenon: We investigate the mechanism of the significant enhancement in the enzymatic saccharification of lignocelluloses at an elevated pH of 5.5–6.0. An elevated pH significantly increases the lignin surface charge, which causes lignin to become more hydrophilic and facilitates the electrostatic interactions between cellulose and lignin to reduce its coordination affinity to cellulase and, consequently, the nonspecific binding of cellulase.
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