Comprehensive transcriptomic and proteomic analyses identify intracellular targets for myriocin to induce Fusarium oxysporum f. sp. niveum cell death.

BACKGROUND: Myriocin is a natural product with antifungal activity and is derived from Bacillus amyloliquefaciens LZN01. Our previous work demonstrated that myriocin can inhibit the growth of Fusarium oxysporum f. sp. niveum (Fon) by inducing membrane damage. In this study, the antifungal actions of myriocin against Fon were investigated with a focus on the effects of myriocin on intracellular molecules. RESULTS: Analysis of DNA binding and fluorescence spectra demonstrated that myriocin can interact with dsDNA from Fon cells. The intracellular-targeted mechanism of action was also supported by transcriptomic and proteomic analyses; a total of 2238 common differentially expressed genes (DEGs) were identified. The DEGs were further verified by RT-qPCR. Most of the DEGs were assigned metabolism and genetic information processing functions and were enriched in ribosome biogenesis in eukaryotes pathway. The expression of some genes and proteins in ribosome biogenesis in eukaryotes pathway was affected by myriocin, primarily the genes controlled by the C6 zinc cluster transcription factor family and the NFYA transcription factor. Myriocin influenced the posttranscriptional processing of gene products by triggering the main RI (retained intron) events of novel alternative splicing; myriocin targeted key genes (FOXG_09470) or proteins (RIOK2) in ribosome biogenesis in eukaryotes pathway, resulting in disordered translation. CONCLUSIONS: In conclusion, myriocin was determined to exhibit activity against Fon by targeting intracellular molecules. The results of our study may help to elucidate the antifungal actions of myriocin against Fon.

Isolation and evaluation of the plant growth promoting rhizobacterium Bacillus methylotrophicus (DD-1) for growth enhancement of rice seedling.

Bacillus methylotrophicus has been demonstrated to promote growth of various plants, whereas the promoting effect of B. methylotrophicus on rice growth has been rarely reported. In this study, B. methylotrophicus DD-1, capable of efficiently promoting the growth of rice, was isolated from the root soil of rice plants. The isolate exhibited potassium-solubilizing (1.18 mg/L), Indole-3-acetic acid (IAA) (87.26 mg/L), Gibberellic acid (GA) (25.91 mg/L) and Siderophore production activity (52.32%). As indicated from the result, plant growth parameters (e.g., dry weight, tiller number, root and shoot length) of rice seedlings treated with the isolate DD-1 were more effective than those of the control group in pot and soilless culture experiments. Moreover, the adsorption capacity of rice roots which were soaked in the bacterial suspension of isolate increased with the increase in concentration and absorption time. In sterilized and unsterilized soil, conformation of root colonization activity by bacterial isolate established by its nearer existence to the rice root. Thus, the B. methylotrophicus DD-1 enhances plant growth promotion by multifarious growth promoting and root colonization traits, thereby augmenting potassium level in soil. Henceforth, the potential bacterium could be exploited for the development of biological fertilizer, leading towards sustainable agronomy.

Research status and hotspots of social frailty in older adults: a bibliometric analysis from 2003 to 2022.

Background: Social Frailty is a significant public health concern affecting the elderly, particularly with the global population aging rapidly. Older adults with social frailty are at significantly higher risk of adverse outcomes such as disability, cognitive impairment, depression, and even death. In recent years, there have been more and more studies on social frailty, but no bibliometrics has been used to analyze and understand the general situation in this field. Therefore, by using CiteSpace, VOSviewer, and Bilioshiny software programs, this study aims to analyze the general situation of the research on social frailties of the older adults and determine the research trends and hot spots. Methods: A bibliometric analysis was conducted by searching relevant literature on the social frailty of the older adults from 2003 to 2022 in the Web of Science core database, using visualization software to map publication volume, country and author cooperation networks, keyword co-occurrences, and word emergence. Results: We analyzed 415 articles from 2003 to 2022. Brazil has the highest number of articles in the field of social frailty of the older adults, and the United States has the highest number of cooperative publications. Andrew MK, from Canada, is the most published and co-cited author, with primary research interests in geriatric assessment, epidemiology, and public health. "Social Vulnerability," "Health," "Frailty," "Mortality," and "Older Adult" are among the research hotspots in this field. "Dementia," "Alzheimer's disease," "Population," and "Covid-19" are emerging research trends in social frailty among the older adults. Conclusion: This scientometric study maps the research hotspots and trends for the past 20 years in social frailty among the older adults. Our findings will enable researchers to better understand trends in this field and find suitable directions and partners for future research.

Emotional inhibition mediates the relationship between maternal postpartum security and pregnancy distress in China: A cross-sectional study.

OBJECTIVE: Pregnancy and childbirth bring not only joy but also a concomitant sense of insecurity, which may adversely affect health, role adaptation, and relationships. This study aimed to explore the risk factors for postpartum mothers' sense of security. METHODS: This cross-sectional study used questionnaires on Parents' Postnatal Sense of Security, Tilburg Pregnancy Distress Scale, and the Emotional Inhibition Scale. Structural equation modeling was used to calculate the mediating effect. RESULTS: The mean postnatal maternal security value was 44.77 ± 9.02. Multiple regression analyses revealed that several factors, including companionship of the partner during pregnancy, number of prenatal visits accompanied by the partner, complications during pregnancy, pregnancy distress, and emotional inhibition, independently predicted maternal security. Moreover, our structural equation model revealed that emotional inhibition significantly influenced maternal postpartum security directly (ß = -0.30, P < 0.001). In addition, pregnancy distress affected maternal security directly (ß = -0.45, P < 0.001) and indirectly (ß = -0.129, P < 0.001) through emotional inhibition. CONCLUSION: This study indicated a lower level of postpartum maternal sense of security. Emotional inhibition partially mediates the relationship between postpartum maternal sense of security and pregnancy distress. Therefore, health care professionals providing guidance to pregnant and postpartum women on proper emotional regulation and early identification of pregnancy distress may be more effective in enhancing their postpartum sense of security.

Membrane disruption of Fusarium oxysporum f. sp. niveum induced by myriocin from Bacillus amyloliquefaciens LZN01.

Myriocin, which is produced by Bacillus amyloliquefaciens LZN01, can inhibit the growth of Fusarium oxysporum f. sp. niveum (Fon). In the present study, the antifungal mechanism of myriocin against Fon was investigated with a focus on the effects of myriocin on the cell membrane. Myriocin decreased the membrane fluidity and destroyed the membrane integrity of Fon. Significant microscopic morphological changes, including conidial shrinkage, the appearance of larger vacuoles and inhomogeneity of electron density, were observed in myriocin-treated cells. A membrane-targeted mechanism of action was also supported by transcriptomic and proteomic analyses; a total of 560 common differentially expressed genes (DEGs) and 285 common differentially expressed proteins (DEPs) were identified. The DEGs were further verified by using RT-qPCR. The combined analysis between the transcriptome and proteome revealed that the expression of some membrane-related genes and proteins, mainly those related to sphingolipid metabolism, glycerophospholipid metabolism, steroid biosynthesis, ABC transporters and protein processing in the endoplasmic reticulum, was disordered. Myriocin affected the serine palmitoyl transferase (SPT) activity as evidenced through molecular docking. Our results indicate that myriocin has significant antifungal activity owing to its ability to induce membrane damage in Fon.

Preparation and characterization of fast-curing powder epoxy adhesive at middle temperature.

At present, the disadvantage of powder epoxy adhesive is the limited application area. In order to widen the application range of powder epoxy adhesive from heat-resistant substrates (such as metals) to heat-sensitive substrates (such as plastic products, cardboard and wood), it is necessary to decrease the curing temperature. In this article, a series of fast-curing powder epoxy adhesives were prepared by the melt blending method with bisphenol A epoxy resin (E-20), hexamethylenetetramine (HMTA) as a curing agent and 2-methylimidazole (2-MI) as an accelerant. The structure and properties of the E-20/HMTA/2-MI systems were characterized by Fourier transform infrared, thermogravimetric analysis, dynamic mechanical analyser and differential scanning calorimetry (DSC). 2-MI added into the E-20/HMTA systems can simultaneously enhance toughness, tensile strength, glass transition temperature (Tg) and thermal stability in comparison with the E-20/HMTA systems. The best mechanical properties were obtained at 100/8/0.6 weight ratio of the E-20/HMTA/2-MI systems. DSC experiments revealed that the exothermic peak of the E-20/HMTA/2-MI system was about 55°C lower than that of the E-20/HMTA system. The activation energy of the cure reaction was determined by both Kissinger's and Ozawa's methods at any heating rates. The activation energy and pre-exponential factor were about 100.3 kJ mol-1 and 3.57 × 1011 s-1, respectively. According to the KAS method, the curing time of the E-20/HMTA/2-MI systems was predicted by evaluating the relationship between temperature and curing time.