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Phosphorus (P) and potassium (K) stress significantly affect the growth, physiological characteristics, and nutrient uptake of rice plants. This study investigated the photosynthetic nitrogen (N) metabolism, N uptake, and N utilization of plants under varied P and K supplies. Two local conventional high-yield rice varieties (Shennong 265 and Liaojing 294) were used. These varieties were subjected to the following hydroponic experimental treatments: HPHK (normal P and K concentrations), HPLK (normal P and 1/20 normal K concentration), LPHK (normal K and 1/20 normal P concentration), and LPLK (1/20 normal P and K concentrations). The results showed that the mesophyll cells had a relatively complete nuclear and chloroplast structures, and the antioxidant enzymes of the plants were significantly reduced under the HPHK treatment. Compared to the LP treatments (LPHK and LPLK), the HPHK treatment was found to have the following potential effects: effectively optimize plant configuration; promote leaf development (Pn, E, Ci, and Tr, chlorophyll, and leaf area index); significantly increase the N-metabolism-related enzyme activity of leaves and roots and the accumulation of N in the plant in the main growth stages; and significantly increase the rice yield and N-related efficiency. In conclusion, the HPHK treatment was found to be beneficial in improving the plant configuration, promoting photosynthetic N metabolism, and increasing grain yield and N-related utilization efficiency. [ABSTRACT FROM AUTHOR]

Northeast China is an important commercial grain base for China, but also the largest japonica rice production area. However, N, and K fertilizer application and unreasonable application times are prominent contradictions that restrict the development of japonica rice. This study aimed to investigate how to rationally apply N and K fertilizers to affect grain filling and ultimately increase the quality of the rice. In this field study, two N application levels and three K application ratios were set in 2020 and 2021 using Shennong 265 (SN265) and Meifengdao 61 (MF61). We found that the final seed growth and filling rate of SN265 were higher than those of MF61, and their filling characteristics were slow in the early stage and fast in the later stage, with large fluctuations. Appropriate reductions and increases of N and K fertilizer applications, respectively, in the early stage could improve grain filling. Compared with SN265, MF61 had a 3.2% increase in head rice rate, lower amylose and protein content, a decrease of chalkiness degree and chalkiness percentage by 23.96 and 34.00%, respectively, and more reasonable protein components. With the N application increase, the processing quality improved, the amylose and protein content and chalkiness increased, the protein components increased except for the milled rice glutelin, and the rice taste value decreased. At low N levels, increasing the proportion of K application was consistent with the effect of increasing N. The taste value of SN265 decreased linearly with the increase in the ratio of N application to pre-application of K, the highest taste value was obtained when the N fertilizer was applied at a rate of 180 kg ha−1, and the ratio of before and after K fertilizer application was about 1:2. The taste value of MF61 decreased linearly with the N application increase and showed a trend of increasing and then decreasing with the K application increase in the early stage. The taste peak gradually shifted back with the N application increase, and the highest taste value was obtained when N fertilizer was applied at 180 kg ha−1; the ratio of before and after K fertilizer application was about 3:2. By constructing the grain-filling quality evaluation system, the characteristic parameters of superior and inferior grains at the early and late stages of grain filling, respectively, greatly affected the rice taste value. Additionally, the percentage of the rice grain weight at the maximum grain-filling rate to the final rice grain weight (I) of superior grains, glutelin content, and value of the RVA profile characteristics were all critical reference indicators for rice taste quality. [ABSTRACT FROM AUTHOR]

The tiller angle, which is an important agronomic trait, determines plant architecture and greatly influences the grain yield of rice. In this study, a population of chromosome segment substitution lines derived from a cross between a japonica variety with a compact plant architecture—Koshihikari—and an indica variety with a spread-out plant architecture—Nona Bokra—was used to investigate the genetic basis of the tiller angle. Five quantitative trait loci (qTA1, qTA5, qTA9-1, qTA9-2, and qTA11) for the tiller angle were detected on chromosomes 1, 5, 9, 9, and 11 in two different environments. The phenotypic variation in these QTLs ranged from 3.78% to 8.22%. Two pairs of digenic epistatic QTLs were detected in Lingshui. The epistatic interaction explained 15.19% and 13.60% of the phenotypic variance, respectively. Among the five QTLs, qTA9-2 was detected in both environments. An F2 mapping population containing the qTA9-2 QTL was established. The location of qTA9-2 was narrowed down to a 187 kb region between InDel markers M9 and M10 on chromosome 9. Thirty open reading frames (ORFs), including TAC1, a gene known to regulate the tiller angle, were identified in this region. The gene sequencing results suggested that a base substitution from G to A at position 1557 in the 3′-untranslated region led to a difference in the expression of qTA9-2 in Koshihikari and Nona Bokra. These findings provide a potential gene resource for the improvement of rice plant architecture. [ABSTRACT FROM AUTHOR]

Chinese hamsters are experimental animals originally from China. They play an important role in experimental research on medicine and biology. They are widely used in life science research, such as genetics, infectious diseases, tissue culture, especially in animal models and mechanism research, such as diabetes and oral cancer. This paper reviews the relevant applied studies of Chinese hamsters in disease animal models since its development, and discusses the advantages and problems associated with the use of these animals in biomedical research.

Autophagy is a highly conservative cellular self-protective behavior dependent on lysosomes, and can be used as an important factor in promoting or preventing cancer, and its effect is related to the type and development of tumors. A full understanding of autophagy pathway is helpful to improve the diagnosis and treatment of tumors. Studies have shown that autophagy is closely related to the occurrence and development of oral tumors. Autophagy-related genes and signal pathways play a dual regulatory role on oral tumors. This article reviews the latest progress in the regulatory mechanism and therapeutic effect of autophagy on oral tumors.

Objective: microRNA‐450b (miR‐450b) plays an important role in cancer progression; however, its function in oral squamous cell carcinoma (OSCC) remains largely unknown. This study aimed to investigate the action mechanisms of miR‐450b in OSCC. Materials and Methods: OSCC animal model was established via continuous induction with single‐drug 7, 12‐dimethylbenzo[a]anthracene (DMBA). Animal tissue samples were pathologically typed using haematoxylin–eosin (HE) staining. The Cancer Genome Atlas (TCGA) database was used to predict miR‐450b and SERPINB2 expression in head and neck squamous cell carcinoma (HNSCC). qRT‐PCR and Western blotting were used to detect gene and protein expression in OSCC tissue and cells, respectively. OSCC cell proliferation, growth, migration and invasion were detected using CCK‐8, colony formation, transwell migration and matrigel invasion assays, respectively. Bioinformatic tools were used to predict miR‐450b target genes. Dual‐luciferase reporter assay was used to verify targeting between miR‐450b and SERPINB2. Finally, small interfering RNA (siRNA) was used to reduce SERPINB2 expression to detect its effect on tumourigenesis. Results: Four stages of OSCC carcinogenesis (normal oral epithelium, simple epithelial hyperplasia, dysplasia and OSCC) were identified. miR‐450b was found to be overexpressed in OSCC animal samples, HNSCC samples and human OSCC cells. Upregulation of miR‐450b significantly promoted OSCC cell proliferation, colony formation, migration and invasion, while its downregulation had the opposite effect. SERPINB2 was found to be a miR‐450b target gene, and its expression was negatively correlated with miR‐450b expression. Altering SERPINB2 expression effectively inhibited OSCC cell invasion, metastasis and epithelial‐mesenchymal transition (EMT). Conclusions: miR‐450b plays a key role in OSCC tumourigenesis by regulating OSCC cell migration, invasion and EMT via SERPINB2. [ABSTRACT FROM AUTHOR]

Based on the data of indexed papers from Inspec database, scientometrics and statistics‐related analysis methods are used to study the overall development trend of international cooperation in advanced manufacturing, the characteristics and evolution of major countries in four dimensions of cooperation scale, cooperation intensity, cooperation dominance rate, cooperation impact, and cooperation network from 2011 to 2020, and this article focuses on the changing trend of China and the differences existing with other countries. The study shows that cooperation in advanced manufacturing has an upward trend, with China and the US having a clear lead in cooperation scale and intensity. China leads the most in the aspect of international cooperation in the field of advanced manufacturing, while the US. is at the heart of a network of cooperation across the field. [ABSTRACT FROM AUTHOR]

Background: The CRISPR/Cas9 system is widely used for genome editing in human, rat and mouse cells. In this study, we established Fzd6 mutant mice using CRISPR/Cas9 technology, and obtained Fzd6 homozygous mutant (Fzd6Q152E) mice through breeding. Fzd6 plays a role in depression, but there are few related reports. We used this model to investigate the mechanism of Fzd6 involved in depression, and build a solid foundation for subsequent in-depth studies. Methods and Results: The target of Fzd6 mutation was obtained by CRISPR/Cas9 technology and hippocampal tissue was collected for Nissl staining and histological analysis. Blood was collected for enzyme linked immunosorbent assay (ELISA); The gene expression of Fzd6 and the related genes expression in wnt pathway was quantified by quantitative real-time PCR (qRT-PCR), and then expression of Fzd6 and proteins in the Wnt pathway were identified by western blotting. ELISA results showed that the expression levels of brain derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT), and Noradrenaline (NE) in serum were significantly decreased in Fzd6Q152E mice, whereas the mRNA expression of Lrp5, Lrp6, and Dkk2 is increased. The western blotting revealed that the expression of Fzd6 and Lrp6 is decreased, although the expression of Dkk2 and Gsk-3β increased. Conclusion: Our study successfully established homozygous Fzd6 mutant mice model. The relationship between Fzd6-Wnt and depression was preliminarily clarified, which provides an ideal animal model for subsequent research on diseases induced by the Fzd6 mutation. [ABSTRACT FROM AUTHOR]