Maize actin depolymerizing factor 1 (ZmADF1) negatively regulates pollen development.

The normal development of pollen grains and the completion of double fertilization in embryos are crucial for both the sexual reproduction of angiosperms and grain production. Actin depolymerizing factor (ADF) regulates growth, development, and responses to biotic and abiotic stress by binding to actin in plants. In this study, the function of the ZmADF1 gene was validated through bioinformatic analysis, subcellular localization, overexpression in maize and Arabidopsis, and knockout via CRISPR/Cas9. The amino acid sequence of ZmADF1 exhibited high conservation and a similar tertiary structure to that of ADF homologs. Subcellular localization analysis revealed that ZmADF1 is localized mainly to the nucleus and cytoplasm. The ZmADF1 gene was specifically expressed in maize pollen, and overexpression of the ZmADF1 gene decreased the number of pollen grains in the anthers of transgenic Arabidopsis plants. The germination rate of pollen and the empty seed shell rate in the fruit pods of the overexpressing plants were significantly greater than those in the wild-type (WT) plants. In maize, the pollen viability of the knockout lines was significantly greater than that of both the WT and the overexpressing lines. Our results confirmed that the ZmADF1 gene was specifically expressed in pollen and negatively regulated pollen quantity, vigor, germination rate, and seed setting rate. This study provides insights into ADF gene function and possible pathways for improving high-yield maize breeding.

Strain Identification and Drug Resistance Analysis of Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry in Nontuberculous Mycobacterial Lung Disease.

Objective: To evaluate the clinical value of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in detecting Nontuberculous mycobacteria (NTM). Methods: The clinical data of 172 patients with suspected NTM lung disease were collected from our hospital from January 1, 2018, to December 30, 2021. The results were compared with those of BACTEC MGIT 960 in liquid culture and gene chip. This study also utilised MALDI-TOF MS to detect macrolide (MA) and amikacin (Am) mutations. Results: One hundred thirty-seven cases of NTM pulmonary disease were confirmed by identifying the NTM gene chip in bronchoalveolar lavage fluid and/or MALDI-TOF MS detection. The positive predictive value and negative predictive value were 100% (131/131) and 85.37% (35/41), respectively, and the consistency of the two methods was high (kappa=0.899). For the drug resistance detection of MAs, the consistency rate between MALDI-TOF MS detection and drug sensitivity detection was 97.71% (128/131), the sensitivity was 81.25% (13/16) and the specificity was 100% (115/115). The positive and negative predictive values were 100% (13/13) and 93.75% (115/118), respectively. There was no coincidental consistency between the two methods, and the consistency was high (P<0.001, kappa=0.884). For the drug resistance test of Am, the consistency rate between the MALDI-TOF MS test and the drug sensitivity test was 93.13% (122/131), the sensitivity was 93.52% (101/108), the specificity was 90.91% (21/23) and the positive predictive value and negative predictive value were 98.06% (101/103) and 75.00% (21/28), respectively. The two methods had high consistency, and the consistency was not coincidental (P<0.001, kappa=0.781). Conclusion: Utilising MALDI-TOF MS has a good consistency with the drug resistance gene chip method and can be a rapid and effective method to identify strains and drug resistance of NTM. Therefore, it has certain clinical application value in patients with suspected NTM lung disease.

How do different ambient temperatures and vehicle speeds affect the cognitive performance of male drivers? Evidence from ERP.

OBJECTIVE: Excessive cold or overheating can cause a decline in driver performance and even serious traffic accidents, but the influence mechanism of ambient temperature and vehicle speeds on drivers' cognitive performance is still unclear. This research developed an easy driving simulator experiment to study driver performance under different ambient temperatures and vehicle speeds. METHOD: Simulated driving tasks were performed by 30 male participants at different speeds in low, medium, and high-temperature environments. A behavioral experiment was adopted, and the average reaction time of emergency braking was used as the evaluation index of driver performance. RESULTS: Both ambient temperature and vehicle speed had a statistically significant relationship with driver's braking reaction time, and the interaction effect was significant. CONCLUSION: Drivers' cognitive efforts in medium-temperature environments were significantly lower than that at high and low temperatures. Compared with previous studies, this study also monitored differences in the activity of drivers' brain regions in three ambient temperatures, providing a physiological basis for measuring drivers' cognitive efforts.

TIPE2 knockout reduces myocardial cell damage by inhibiting IFN-γ-mediated ferroptosis.

Acute rejection of the transplanted heart is mediated by oxidative programmed cell death through the synergistic effects of the innate and adaptive immune systems. However, the role of ferroptosis, a newly discovered form of oxidative cell death, has not been widely evaluated. Tumor necrosis factor-α-induced protein-8 like 2 (TNFAIP8L2), also known as TIPE2, is required for maintaining immune homeostasis. To characterize the role of TIPE2 in mediating heart allografts, BALB/c hearts were transplanted into C57BL/6 wild-type (WT) and TIPE2-/- recipient mice. In TIPE2-/- recipient mice, allograft injury in BALB/c allograft hearts was significantly reduced through the inhibition of allograft ferroptosis. On day 3 and day 6 post-transplantation, the numbers of CD3+, CD4+, and CD8+ cells among splenocytes and draining lymph node cells were significantly decreased, and the activation of CD4+ and CD8+ cells in grafts was decreased in TIPE2-/- recipient mice compared with WT mice. Moreover, CD4+ and CD8+ T cells in TIPE2-/- recipient mice were characterized by deficient capacities for interferon-γ (IFN-γ) production through the TBK1 signaling axis and increased glutathione peroxidase 4 (GPX4). In cell experiments, treatment with IFN-γ enhanced ferroptosis-specific lipid peroxidation in myocardial cells and correlated inversely with GPX4 expression. Mechanistically, IFN-γ administration decreased the expression of GPX4 by inhibiting MEK/ERK phosphorylation. In summary, our findings demonstrated that TIPE2 deficiency inhibits T-cell production of IFN-γ to reduce ferroptosis in allografts by restraining lipid peroxidation.

Safety and biodistribution of exosomes derived from human induced pluripotent stem cells.

As a new cell-free therapy, exosomes have provided new ideas for the treatment of various diseases. Human induced pluripotent stem cells (hiPSCs) cannot be used in clinical trials because of tumorigenicity, but the exosomes derived from hiPSCs may combine the advantages of iPSC pluripotency and the nanoscale size of exosomes while avoiding tumorigenicity. Currently, the safety and biodistribution of hiPSC-exosomes in vivo are unclear. Here, we investigated the effects of hiPSC-exosomes on hemolysis, DNA damage, and cytotoxicity through cell experiments. We also explored the safety of vein injection of hiPSC-exosomes in rabbits and rats. Differences in organ distribution after nasal administration were compared in normal and Parkinson's disease model mice. This study may provide support for clinical therapy and research of intravenous and nasal administration of hiPSC-exosomes.

Application of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the detection of drug resistance of Mycobacterium tuberculosis in re-treated patients.

OBJECTIVE: To evaluate the value of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in the detection of drug resistance of Mycobacterium tuberculosis in re-treated patients. METHODS: MALDI-TOF MS was used to detect the resistance of 202 cases of retreatment pulmonary tuberculosis infection strains to isoniazid (INH), rifampin (RFP), ethambutol (EMB), streptomycin (SM), ofloxacin (Ofx), moxifloxacin (Mfx), amikacin (Am), Kanamycin (Km) and capreomycin (Cm), and the results were compared with those of BACTEC 960 liquid culture detection to compare the coincidence rate of the two methods. RESULTS: MALDI-TOF MS detected 60 copies of Mtb gene mutation, and drug-resistant gene mutation strains accounted for 34.68% (60/173) of positive strains. Rifampicin-related rpoB gene mutations accounted for 86.67% (52/60), isoniazid-related katG + inhA gene mutations accounted for 80.00% (48/60) and inhA-15 gene mutations accounted for 8.33% (5/60), streptomycin-related rpsL gene mutations accounted for 28.33% (17/60), ethambutol-related embB gene mutations accounted for 45.00% (27/60), quinolone-related gyrA basic mutation accounted for 26.67% (16/60), ethyl/propylthiamine-related embB gene mutation accounted for 36.67% (22/60) and inhA-15 gene mutation accounted for 10.00% (6/60), aminoglycoside-related rrs gene mutation accounted for 26.67% (16/60), clofazimine Fazimine, bedaquiline related Rv0678 193 gene mutations accounted for 3.33% (2/60), pyrazinamide, p-aminosalicylate, linezolid were not seen mutated genes. Multi-gene mutant strains accounted for 63.33% (38/60) of drug-resistant strains. CONCLUSION: MALDI-TOF MS assay has good agreement with BACTEC960 liquid culture drug sensitivity test, which can be a rapid and effective method to screen for drug resistance of Mycobacterium tuberculosis, and has some clinical application value in patients with relapse tuberculosis.

The miR528-D3 Module Regulates Plant Height in Rice by Modulating the Gibberellin and Abscisic Acid Metabolisms.

Plant height, as one of the important agronomic traits of rice, is closely related to yield. In recent years, plant height-related genes have been characterized and identified, among which the DWARF3 (D3) gene is one of the target genes of miR528, and regulates rice plant height and tillering mainly by affecting strigolactone (SL) signal transduction. However, it remains unknown whether the miR528 and D3 interaction functions in controlling plant height, and the underlying regulatory mechanism in rice. In this study, we found that the plant height, internode length, and cell length of internodes of d3 mutants and miR528-overexpressing (OE-miR528) lines were greatly shorter than WT, D3-overexpressing (OE-D3), and miR528 target mimicry (OE-MIM528) transgenic plants. Knockout of D3 gene (d3 mutants) or miR528-overexpressing (OE-miR528) triggers a substantial reduction of gibberellin (GA) content, but a significant increase of abscisic acid (ABA) accumulation than in WT. The d3 and OE-miR528 transgenic plants were much more sensitive to GA, but less sensitive to ABA than WT. Moreover, the expression level of GA biosynthesis-related key genes, including OsCPS1, OsCPS2, OsKO2 and OsKAO was remarkably higher in OE-D3 plants, while the NECD2 expression, a key gene involved in ABA biosynthesis, was significantly higher in d3 mutants than in WT and OE-D3 plants. The results indicate that the miR528-D3 module negatively regulates plant height in rice by modulating the GA and ABA homeostasis, thereby further affecting the elongation of internodes, and resulting in lower plant height, which adds a new regulatory role to the D3-mediated plant height controlling in rice.

Period 2 Suppresses the Malignant Cellular Behaviors of Colorectal Cancer Through the Epithelial-Mesenchymal Transformation Process.

INTRODUCTION: The PER2 (Period circadian regulator 2) gene is related to the circadian clock, and it has been deemed as a suppressor gene in osteosarcoma and lung carcinoma. However, the part of PER2 in CRC (colorectal cancer) needs to be further determined. METHODS: First, we collected clinical samples to detect PER2 expression in CRC. Then, we used cell transfection to knock down PER2 expression in CRC cell lines and performed a series of functional experiments to elucidate the effects of PER2 on CRC cells. We next verified whether PER2 affects the epithelial-mesenchymal transformation (EMT) process in CRC by conducting quantitative real-time PCR and western blotting. RESULTS: In the research, we revealed that the expression of PER2 decreased in CRC clinical samples. In addition, knocking down PER2 expression caused CRC cells to acquire malignant biological features. Finally, we found that PER2 knockdown may activate the Snail/Slug axis through inhibiting p53, therefore promote the activation of the EMT pathway. CONCLUSION: In conclusion, low PER2 expression reinforces migration and activates EMT in CRC, suggesting that PER2 is closely related to CRC development and could be used as a potential treatment site in the clinic.

PAK3 promotes the metastasis of hepatocellular carcinoma by regulating EMT process.

Purpose: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. The malignant biological behavior of HCC is closely related to epithelial-mesenchymal transition (EMT), and EMT plays an important role in the progression, migration and metastasis of HCC. P21-activated kinase 3 (PAK3) is a serine/threonine protein kinase, and PAK3 affects the EMT, proliferation, metastasis and invasion of HCC. Methods: In this study, the relationship between PAK3 and HCC was first analyzed by bioinformatics, and then, the expression of PAK3 in clinical samples was detected by immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR) and Western blotting. Subsequently, the expression of PAK3 was further confirmed in HCC cells. In addition, after the overexpression or knockdown of PAK3 in cells, the proliferation, migration and invasion abilities of these cells were assessed by Cell Counting Kit-8 (CCK-8), wound healing and Transwell assays, and the results were confirmed in vivo experiments in mice. In addition, we also verified that PAK3 affected the EMT and EMT-related pathway of HCC through qRT-PCR, Western blotting and immunofluorescence experiments. Results: Through database analysis, we found that PAK3 was highly expressed in HCC patients and was positively correlated with tumor stage and grade, suggesting that PAK3 expression was closely related to HCC occurrence and development. We subsequently confirmed that PAK3 was overexpressed in HCC clinical samples and HCC cell lines and that PAK3 promoted the proliferation, migration and invasion of HCC cells in vitro. Finally, we found that PAK3 regulated EMT-related molecule expression and EMT-related TGF-ß/smad signaling pathway. Conclusion: High expression of PAK3 enhances the invasion of HCC and regulates EMT, suggesting that PAK3 may be a potential target for the treatment of HCC.

Application of natural products for inducing ferroptosis in tumor cells.

Ferroptosis is a regulated cell death pathway based on the deposition of lipid-based reactive oxygen species (L-ROS) in the presence of iron ions. The term was first coined in 2012 by Dixon. Decreased glutathione (GSH) synthesis and low glutathione-dependent antioxidant peroxidase 4 (GPX4) activity are the major causes of ferroptosis. Sensitivity to ferroptosis for example in tumor cells may be further enhanced by high cellular iron concentrations and/or high p53 levels. Therefore, driving ferroptosis in tumor cells could be a new way to treat tumors. Thus far, natural products have played considerable roles in antitumor research and treatment, and some drugs, such as paclitaxel, have proven beneficial in many cancer patients. According to current research, natural products can induce ferroptosis when used alone or in conjunction with other cancer therapies. This review mainly elaborates the main mechanism of ferroptosis and the regulating effects of some natural products on ferroptosis, aiming to create a new space for the research and development of novel anticancer drugs.

Identification of crucial genes of pyrimidine metabolism as biomarkers for gastric cancer prognosis.

BACKGROUND: Metabolic reprogramming has been reported in various kinds of cancers and is related to clinical prognosis, but the prognostic role of pyrimidine metabolism in gastric cancer (GC) remains unclear. METHODS: Here, we employed DEG analysis to detect the differentially expressed genes (DEGs) in pyrimidine metabolic signaling pathway and used univariate Cox analysis, Lasso-penalizes Cox regression analysis, Kaplan-Meier survival analysis, univariate and multivariate Cox regression analysis to explore their prognostic roles in GC. The DEGs were experimentally validated in GC cells and clinical samples by quantitative real-time PCR. RESULTS: Through DEG analysis, we found NT5E, DPYS and UPP1 these three genes are highly expressed in GC. This conclusion has also been verified in GC cells and clinical samples. A prognostic risk model was established according to these three DEGs by Univariate Cox analysis and Lasso-penalizes Cox regression analysis. Kaplan-Meier survival analysis suggested that patient cohorts with high risk score undertook a lower overall survival rate than those with low risk score. Stratified survival analysis, Univariate and multivariate Cox regression analysis of this model confirmed that it is a reliable and independent clinical factor. Therefore, we made nomograms to visually depict the survival rate of GC patients according to some important clinical factors including our risk model. CONCLUSION: In a word, our research found that pyrimidine metabolism is dysregulated in GC and established a prognostic model of GC based on genes differentially expressed in pyrimidine metabolism.

miR-539 activates the SAPK/JNK signaling pathway to promote ferropotosis in colorectal cancer by directly targeting TIPE.

Colorectal cancer (CRC) is a common tumor that harms human health with a high recurrence rate. It has been reported that the expression of microRNA-539 (miR-539) is low in several types of cancer, including CRC. Tumor necrosis factor (TNF)-α-induced protein 8 (TNFAIP8/TIPE) is highly expressed in CRC and promotes the proliferation, migration and angiogenesis of CRC. However, the relationship between miR-539 and TIPE and the mechanisms by which they regulate the proliferation of CRC remain to be explored. We aimed to investigate the functions and mechanisms of miR-539 in CRC proliferation. Functionally, miR-539 can bind to and regulate the expression of TIPE, and miR-539 activates SAPK/JNK to downregulate the expression of glutathione peroxidase 4 (GPX4) and promote ferroptosis. Our data reveal the novel role of miR-539 in regulating ferroptosis in CRC via activation of the SAPK/JNK axis, providing new insight into the mechanism of abnormal proliferation in CRC and a novel potential therapeutic target for advanced CRC.

Emerging roles of nucleotide metabolism in cancer development: progress and prospect.

Abnormal cancer metabolism occurs throughout the development of tumors. Recent studies have shown that abnormal nucleotide metabolism not only accelerates the development of tumors but also inhibits the normal immune response in the tumor microenvironment. Although few relevant experiments and reports are available, study of the interaction between nucleotide metabolism and cancer development is rapidly developing. The intervention, alteration or regulation of molecular mechanisms related to abnormal nucleotide metabolism in tumor cells has become a new idea and strategy for the treatment of tumors and prevention of recurrence and metastasis. Determining how nucleotide metabolism regulates the occurrence and progression of tumors still needs long-term and extensive research and exploration.

Candida albicans disorder is associated with gastric carcinogenesis.

Background: Bacterial infection is associated with gastric carcinogenesis. However, the relationship between nonbacterial components and gastric cancer (GC) has not been fully explored. We aimed to characterize the fungal microbiome in GC. Methods: We performed ITS rDNA gene analysis in cancer lesions and adjacent noncancerous tissues of 45 GC cases from Shenyang, China. Obtaining the OTUs and combining effective grouping, we carried out species identifications, alpha and beta diversity analyses, and FUNGuild functional annotation. Moreover, differences were compared and tested between groups to better investigate the composition and ecology of fungi associated with GC and find fungal indicators. Results: We observed significant gastric fungal imbalance in GC. Principal component analysis revealed separate clusters for the GC and control groups, and Venn diagram analysis indicated that the GC group showed a lower OTU abundance than the control. At the genus level, the abundances of 15 fungal biomarkers distinguished the GC group from the control, of which Candida (p = 0.000246) and Alternaria (p = 0.00341) were enriched in GC, while Saitozyma (p = 0.002324) and Thermomyces (p = 0.009158) were decreased. Combining the results of Welch's t test and Wilcoxon rank sum test, Candida albicans (C. albicans) was significantly elevated in GC. The species richness Krona pie chart further revealed that C. albicans occupied 22% and classified GC from the control with an area under the receiver operating curve (AUC) of 0.743. Random forest analysis also confirmed that C. albicans could serve as a biomarker with a certain degree of accuracy. Moreover, compared with that of the control, the alpha diversity index was significantly reduced in the GC group. The Jaccard distance index and the Bray abundance index of the PCoA clarified separate clusters between the GC and control groups at the species level (p = 0.00051). Adonis (PERMANOVA) analysis and ANOVA showed that there were significant differences in fungal structure among groups (p = 0.001). Finally, FUNGuild functional classification predicted that saprotrophs were the most abundant taxa in the GC group. Conclusions: This study revealed GC-associated mycobiome imbalance characterized by an altered fungal composition and ecology and demonstrated that C. albicans can be a fungal biomarker for GC. With the significant increase of C. albicans in GC, the abundance of Fusicolla acetilerea, Arcopilus aureus, Fusicolla aquaeductuum were increased, while Candida glabrata, Aspergillus montevidensis, Saitozyma podzolica and Penicillium arenicola were obviously decreased. In addition, C. albicans may mediate GC by reducing the diversity and richness of fungi in the stomach, contributing to the pathogenesis of GC.

Distribution of As, Cd, and Pb in seafood in Southern China and their oral bioavailability in mice.

The distribution of the toxic elements As, Cd, and Pb in nine different types of seafood from Shenzhen, China, was investigated by using inductively coupled plasma mass spectrometry (ICP-MS). The results revealed that the concentrations of arsenic (As) in fish (Lutjanus erythropterus, Paralichthys olivaceus) and in bivalve (Meretrix meretrix) and cadmium (Cd) in scallop (Argopecten irradians) exceed the limits established by food safety regulations in China and EU (European Union). Furthermore, the bioavailability of As, Cd, and lead (Pb) in mice after 20-day oral ingestion of Crassostrea rivularis was investigated, and the total rate of absorption of toxic elements in samples from the liver and kidney tissues and blood was determined. The results of this in vivo trial indicated that the oral bioavailability of As, Cd, and Pb was approximately 0.33, 0.45, and 0.74%, respectively.