Adjustment of scRNA-seq data to improve cell-type decomposition of spatial transcriptomics.

Most sequencing-based spatial transcriptomics (ST) technologies do not achieve single-cell resolution where each captured location (spot) may contain a mixture of cells from heterogeneous cell types, and several cell-type decomposition methods have been proposed to estimate cell type proportions of each spot by integrating with single-cell RNA sequencing (scRNA-seq) data. However, these existing methods did not fully consider the effect of distribution difference between scRNA-seq and ST data for decomposition, leading to biased cell-type-specific genes derived from scRNA-seq for ST data. To address this issue, we develop an instance-based transfer learning framework to adjust scRNA-seq data by ST data to correctly match cell-type-specific gene expression. We evaluate the effect of raw and adjusted scRNA-seq data on cell-type decomposition by eight leading decomposition methods using both simulated and real datasets. Experimental results show that data adjustment can effectively reduce distribution difference and improve decomposition, thus enabling for a more precise depiction on spatial organization of cell types. We highlight the importance of data adjustment in integrative analysis of scRNA-seq with ST data and provide guidance for improved cell-type decomposition.

Hollow Mesoporous Silica Nanoparticles as a New Nanoscale Resistance Inducer for Fusarium Wilt Control: Size Effects and Mechanism of Action.

In agriculture, soil-borne fungal pathogens, especially Fusarium oxysporum strains, are posing a serious threat to efforts to achieve global food security. In the search for safer agrochemicals, silica nanoparticles (SiO2NPs) have recently been proposed as a new tool to alleviate pathogen damage including Fusarium wilt. Hollow mesoporous silica nanoparticles (HMSNs), a unique class of SiO2NPs, have been widely accepted as desirable carriers for pesticides. However, their roles in enhancing disease resistance in plants and the specific mechanism remain unknown. In this study, three sizes of HMSNs (19, 96, and 406 nm as HMSNs-19, HMSNs-96, and HMSNs-406, respectively) were synthesized and characterized to determine their effects on seed germination, seedling growth, and Fusarium oxysporum f. sp. phaseoli (FOP) suppression. The three HMSNs exhibited no side effects on cowpea seed germination and seedling growth at concentrations ranging from 100 to 1500 mg/L. The inhibitory effects of the three HMSNs on FOP mycelial growth were very weak, showing inhibition ratios of less than 20% even at 2000 mg/L. Foliar application of HMSNs, however, was demonstrated to reduce the FOP severity in cowpea roots in a size- and concentration-dependent manner. The three HMSNs at a low concentration of 100 mg/L, as well as HMSNs-19 at a high concentration of 1000 mg/L, were observed to have little effect on alleviating the disease incidence. HMSNs-406 were most effective at a concentration of 1000 mg/L, showing an up to 40.00% decline in the disease severity with significant growth-promoting effects on cowpea plants. Moreover, foliar application of HMSNs-406 (1000 mg/L) increased the salicylic acid (SA) content in cowpea roots by 4.3-fold, as well as the expression levels of SA marker genes of PR-1 (by 1.97-fold) and PR-5 (by 9.38-fold), and its receptor gene of NPR-1 (by 1.62-fold), as compared with the FOP infected control plants. Meanwhile, another resistance-related gene of PAL was also upregulated by 8.54-fold. Three defense-responsive enzymes of POD, PAL, and PPO were also involved in the HMSNs-enhanced disease resistance in cowpea roots, with varying degrees of reduction in activity. These results provide substantial evidence that HMSNs exert their Fusarium wilt suppression in cowpea plants by activating SA-dependent SAR (systemic acquired resistance) responses rather than directly suppressing FOP growth. Overall, for the first time, our results indicate a new role of HMSNs as a potent resistance inducer to serve as a low-cost, highly efficient, safe and sustainable alternative for plant disease protection.

Investigating the neuroprotective potential of rAAV2-PCBP1-EGFP gene therapy against a 6-OHDA-induced model of Parkinson's disease.

OBJECTIVES: Previous studies have suggested a potential link between poly(rC)-binding protein 1 (PCBP1) and neurodegenerative diseases, including Parkinson's disease (PD). However, the precise role of PCBP1 in the pathogenesis of PD remains unclear. Therefore, the main objective of this study was to investigate the neuroprotective effects of PCBP1 in a PD model. METHODS: To evaluate the neuroprotective potential of PCBP1, we conducted cell count assays and observed the expression of heat shock protein 70 (HSP70) in SH-SY5Y cells exposed to 6-OHDA-induced neurotoxicity. Additionally, we utilized recombinant adeno-associated virus (rAAV2) vectors encoding PCBP1 or EGFP, which were injected into the rat striatum. After 2 weeks of vector or saline injection, 6-OHDA was administered to the rat striatum. Behavioral assessments using the open field test (OFT) were performed weekly for 7 weeks. At the seventh week after 6-OHDA injection, immunohistochemistry and protein expression analyses were conducted in the three groups. RESULTS: The results indicated that PCBP1 treatment significantly reduced the proliferation of 6-OHDA-induced SH-SY5Y cells. Additionally, in surviving cells, overexpression of PCBP1 enhanced the expression of HSP70. Similarly, rAAV2 vectors effectively delivered PCBP1 into the brain, resulting in sustained expression of rAAV2-PCBP1-EGFP. In the OFT, PCBP1 exhibited significant improvements in behavioral abnormalities and reduced anxiety in the PD model rats (p < .01). Moreover, PCBP1 effectively prevented the decrease of tyrosine hydroxylase and HSP70 expression in the lesioned side induced by 6-OHDA (p < .01). Consistent with expectations, PCBP1 efficiently protected against cell death caused by 6-OHDA (p < .01). CONCLUSIONS: In conclusion, our findings provide compelling evidence for the beneficial effects of PCBP1 in the PD model, suggesting that PCBP1 could be a potential therapeutic target for PD.

Toxicity and Behavior-Altering Effects of Three Nanomaterials on Red Imported Fire Ants and Their Effectiveness in Combination with Indoxacarb.

The red imported fire ant (Solenopsis invicta Buren) is one of the 100 worst invasive alien species in the world. At present, the control of red imported fire ants is still mainly based on chemical control, and the most commonly used is indoxacarb bait. In this study, the contact and feeding toxicity of 16 kinds of nanomaterials to workers, larvae, and reproductive ants were evaluated after 24 h, 48 h, and 72 h. The results showed that the mortality of diatomite, Silica (raspberry-shaped), and multi-walled carbon nanotubes among workers reached 98.67%, 97.33%, and 68%, respectively, after contact treatment of 72 h. The mortality of both larval and reproductive ants was less than 20% after 72 h of treatment. All mortality rates in the fed treatment group were below 20% after 72 h. Subsequently, we evaluated the digging, corpse-removal, and foraging behaviors of workers after feeding with diatomite, Silica (raspberry-shaped), and multi-walled carbon nanotubes for 24 h, which yielded inhibitory effects on the behavior of red imported fire ants. The most effective was diatomite, which dramatically decreased the number of workers that dug, extended the time needed for worker ant corpse removal and foraging activities, decreased the number of workers that foraged, and decreased the weight of the food carried by the workers. In addition, we also evaluated the contact and feeding toxicity of these three nanomaterials in combination with indoxacarb on red imported fire ants. According to contact toxicity, after 12 h of contact treatment, the death rate among the red imported fire ants exposed to the three materials combined with indoxacarb reached more than 97%. After 72 h of exposure treatment, the mortality rate of larvae was more than 73% when the nanomaterial content was above 1% and 83% when the diatomite content was 0.5%, which was significantly higher than the 50% recorded in the indoxacarb control group. After 72 h of feeding treatment, the mortality of diatomite, Silica (raspberry-shaped), and multi-walled carbon nanotubes combined with indoxacarb reached 92%, 87%, and 98%, respectively. The death rates of the three kinds of composite ants reached 97%, 67%, and 87%, respectively. The three kinds of composite food had significant inhibitory effects on the behavior of workers, and the trend was largely consistent with the effect of nanomaterials alone. This study provides technical support for the application of nanomaterials in red imported fire ant control.

Antifungal Activity and Mechanism of Xenocoumacin 1, a Natural Product from Xenorhabdus nematophila against Sclerotinia sclerotiorum.

Sclerotinia sclerotiorum (Lib.) de Bary, a polyphagous necrotrophic fungal pathogen, has brought about significant losses in agriculture and floriculture. Until now, the most common method for controlling S. sclerotiorum has been the application of fungicides. Xenocoumacin 1 (Xcn1) is a potential biopesticide having versatile antimicrobial activities, generated by Xenorhabdus nematophila. This study was intended to isolate Xcn1 from X. nematophila YL001 and clarify its efficacies for S. sclerotiorum control. Xcn1 demonstrated a wider antifungal spectrum against 10 plant-pathogenic fungi. It also exhibited a strong inhibitory effect on the mycelial growth of S. sclerotiorum with an EC50 value of 3.00 µg/mL. Pot experiments indicated that Xcn1 effectively inhibited disease extension on oilseed rape and broad bean plants caused by S. sclerotiorum. Morphological and ultrastructural observations revealed that the hyphae of S. sclerotiorum became twisted, shriveled, and deformed at the growing points after treatment with Xcn1 at 3.00 µg/mL and that the subcellular fractions also became abnormal concurrently, especially the mitochondrial structure. Moreover, Xcn1 also increased cell membrane permeability and decreased the content of exopolysaccharide as well as suppressing the activities of polygalacturonase and cellulase of S. sclerotiorum, but exerted no effects on oxalic acid production. This study demonstrated that Xcn1 has great potential to be developed as a new biopesticide for the control of S. sclerotiorum.

Photoactivated 9-methylacridine destroys midgut tissues of Aedes aegypti larvae by targeting ROS-mediated apoptosis in the mitochondrial pathway of midgut cells.

An aromatic ring-containing compound with a wide range of biological activities, 9-methylacridine (AD-9-Me) is a precursor for the synthesis of various drugs. However, its photoactivation properties and mechanism of damage as a photo activator against Aedes aegypti are unknown. The toxic effects of AD-9-Me on Aedes aegypti mosquitoes were determined under light and non-light conditions. The results showed that the toxicity of AD-9-Me to mosquito larvae was significantly higher than that of the dark treatment after 24 h of light exposure; AD-9-Me was mainly distributed in the midgut of larvae, after 24 h of treatment, it can cause an increase in calcium ion concentration, reactive oxygen species (ROS) eruption and ROS accumulation by blocking the ROS elimination pathway in midgut cells. This in turn caused an increase in protein carbonyl and malondialdehyde (MDA) content, a decrease in mitochondrial membrane potential (MMP), a disruption of the barrier function of midgut tissues, a significant decrease in midgut weight and chitin content, which induced the up-regulation of AeDronc, AeCaspase8 and AeCaspase7 genes, leading to apoptotic cell death. In this study, we confirmed that AD-9-Me has photoactivation activity and mainly acts on the midgut of mosquito larvae, which can generate a large amount of ROS in the cells of the midgut and induce apoptosis to occur, resulting in the disruption of the function of the tissues of mosquito larvae, accelerating the death and delaying the development of the mosquito larvae.

Hypidone hydrochloride (YL-0919) protects mice from meningitis via Sigma1R-STAT1-NLRP3-GSDMD pathway.

BACKGROUND: A growing number of studies have found that antidepressants have anti-inflammatory effects while protecting nerves. Hypidone hydrochloride (YL-0919) is a novel highly selective 5-HT reuptake blocker. Our previous studies have demonstrated that YL-0919 exerts notable antidepressant- and anxiolytic-like as well as procognitive effects. However, whether YL-0919 can be used to treat inflammatory and infectious diseases remain unknown. In this study, we aimed to verify the anti-inflammatory effect of YL-0919 on bacterial meningitis and further explore the potential molecular mechanisms. METHODS: We performed the experiments on pneumococcal meningitis mice in vivo and S. pneumoniae infected macrophages/microglia in vitro, with or without YL-0919 treatment. Cognitive function was evaluated by open-field task, Morris water maze test, and novel object recognition test. Histopathological staining and immunofluorescence staining were used to detect the pathological damage of meningitis and NLRP3 inflammasome activation in microglia/macrophages. The expression of the STAT1/NLRP3/GSDMD signal pathway was measured by western blots. Proinflammatory cytokines associated with pyroptosis were detected by ELISA. RESULTS: YL-0919 protected mice from fatal pneumococcal meningitis, characterized by attenuated cytokine storms, decreased bacterial loads, improved neuroethology, and reduced mortality. NLRP3 plays a key role in the regulation of inflammation. When the underlying mechanisms were investigated, we found that YL-0919 inhibited the activation of NLRP3 via STAT1, and thus inhibited macrophages/microglia pyroptosis, resulting in downregulation of proinflammatory cytokines. In addition, Sigma1R was identified as a pivotal receptor that can be engaged by YL-0919 to inhibit NLRP3 activation and pyroptosis pathway in microglia/macrophages. CONCLUSIONS: These results provide new insights into the mechanisms of inflammation regulation mediated by the antidepressant YL-0919. Moreover, targeting the STAT1/NLRP3 pyroptosis pathway is a promising strategy for the treatment of infectious diseases like bacterial meningitis.

5-HT7R enhances neuroimmune resilience and alleviates meningitis by promoting CCR5 ubiquitination.

INTRODUCTION: Excessive immune activation induces tissue damage during infection. Compared to external strategies to reconstruct immune homeostasis, host balancing ways remain largely unclear. OBJECTIVES: Here we found a neuroimmune way that prevents infection-induced tissue damage. METHODS: By FACS and histopathology analysis of brain Streptococcus pneumonia meningitis infection model and behavioral testing. Western blot, co-immunoprecipitation, and ubiquitination analyze the Fluoxetine initiate 5-HT7R-STUB1-CCR5 K48-linked ubiquitination degradation. RESULTS: Fluoxetine, a selective serotonin reuptake inhibitor, or the agonist of serotonin receptor 5-HT7R, protects mice from meningitis by inhibiting CCR5-mediated excessive immune response and tissue damage. Mechanistically, the Fluoxetine-5-HT7R axis induces proteasome-dependent degradation of CCR5 via mTOR signaling, and then recruits STUB1, an E3 ubiquitin ligase, to initiate K48-linked polyubiquitination of CCR5 at K138 and K322, promotes its proteasomal degradation. STUB1 deficiency blocks 5-HT7R-mediated CCR5 degradation. CONCLUSION: Our results reveal a neuroimmune pathway that balances anti-infection immunity via happiness neurotransmitter receptor and suggest the 5-HT7R-CCR5 axis as a potential target to promote neuroimmune resilience.

Analysis of related factors of behavioral problems in children with congenital pseudarthrosis of tibia

SUMMARY OBJECTIVE: This study aimed to investigate the factors associated with behavioral problems in children with congenital pseudarthrosis of the tibia. METHODS: Random sampling is utilized to obtain a sample of 90 patients. The behavioral problems of the patients are detected by Achenbach Children's Behavior Scale. Parental emotional problems are investigated by the Self-Rating Depression Scale and Self-Rating Anxiety Scale. RESULTS: The results demonstrate that the detection rate of behavioral problems in children with congenital pseudarthrosis of the tibia is 53.3% (48/90). Among these behavioral problems, an abnormal rate is higher in the four dimensions: thinking, violation of discipline, social interaction, and aggression. The anxiety and depression scores of caregivers are statistically higher in the abnormal group than in the normal group. The results of the multivariate analysis show that the anxiety degree of the parents had a significant impact on the behavior of the children. CONCLUSIONS: Children with congenital pseudarthrosis of the tibia are facing the issues of high rates of behavioral problems. Parents of children with congenital pseudarthrosis of the tibia had higher levels of anxiety and depression than parents of normal children. The anxiety and depressive state of mind of parents or caregivers had a significant impact on the behavior of children with congenital pseudarthrosis of the tibia.