Effects of nitrogen addition on rhizosphere priming: The role of stoichiometric imbalance.

Nitrogen (N) input has a significant impact on the availability of carbon (C), nitrogen (N), and phosphorus (P) in the rhizosphere, leading to an imbalanced stoichiometry in microbial demands. This imbalance can result in energy or nutrient limitations, which, in turn, affect C dynamics during plant growth. However, the precise influence of N addition on the C:N:P imbalance ratio and its subsequent effects on rhizosphere priming effects (RPEs) remain unclear. To address this gap, we conducted a 75-day microcosm experiment, varying N addition rates (0, 150, 300 kg N ha-1), to examine how microbes regulate RPE by adapting to stoichiometry and maintaining homeostasis in response to N addition, using the 13C natural method. Our result showed that N input induced a stoichiometric imbalance in C:N:P, leading to P or C limitation for microbes during plant growth. Microbes responded by adjusting enzymatic stoichiometry and functional taxa to preserve homeostasis, thereby modifying the threshold element ratios (TERs) to cope with the C:N:P imbalance. Microbes adapted to the stoichiometric imbalance by reducing TER, which was attributed to a reduction in carbon use efficiency. Consequently, we observed higher RPE under P limitation, whereas the opposite trend was observed under C or N limitation. These results offer novel insights into the microbial regulation of RPE variation under different soil nutrient conditions and contribute to a better understanding of soil C dynamics.

Single-cell transcriptomes reveal a molecular link between diabetic kidney and retinal lesions.

The occurrence of diabetic nephropathy (DN) and diabetic retinopathy (DR) are closely associated in patients with diabetes. However, the cellular and molecular linkage of DN and DR has not been elucidated, and further revelations are needed to improve mutual prognostic decisions and management. Here, we generate and integrate single-cell RNA sequencing profiles of kidney and retina to explore the cellular and molecular association of kidney and retina in both physiological and pathological conditions. We find renal mesangial cells and retinal pericytes share molecular features and undergo similar molecular transitions under diabetes. Furthermore, we uncover that chemokine regulation shared by the two cell types is critical for the co-occurrence of DN and DR, and the chemokine score can be used for the prognosis of DN complicated with DR. These findings shed light on the mechanism of the co-occurrence of DN and DR and could improve the prevention and treatments of diabetic microvascular complications.

Deciphering the dual role of bacterial communities in stabilizing rhizosphere priming effect under intra-annual change of growing seasons.

The rhizosphere priming effect (RPE) is a widely observed phenomenon affecting carbon (C) turnover in plant-soil systems. While multiple cropping and seasonal changes can have significant impacts on RPE, the mechanisms driving these processes are complex and not yet fully understood. Here, we planted maize in paddy soil during two growing seasons having substantial temperature differences [May-August (warm season, 26.6 °C) and September-November (cool season, 23.1 °C)] within the same calendar year in southern China to examine how seasonal changes affect RPEs and soil C. We identified sources of C emissions by quantifying the natural abundance of 13C and determined microbial metabolic limitations or efficiency and functional genes related to C cycling using an enzyme-based biogeochemical equilibrium model and high-throughput quantitative PCR-based chip technology, respectively. Results showed that microbial metabolism was mainly limited by phosphorus in the warm season, but by C in the cool season, resulting in positive RPEs in both growing seasons, but no significant differences (9.02 vs. 6.27 mg C kg-1 soil day-1). The RPE intensity remained stable as temperature increased (warm season compared to a cool season), which can be largely explained by the simultaneous increase in the abundance of functional genes related to both C degradation and fixation. Our study highlights the simultaneous response and adaptation of microbial communities to seasonal changes and hence contributes to an understanding and prediction of microbially mediated soil C turnover under multiple cropping systems.

LINE-1 repression in Epstein-Barr virus-associated gastric cancer through viral-host genome interaction.

Long INterspersed Element 1 (LINE-1 or L1) acts as a major remodeling force in genome regulation and evolution. Accumulating evidence shows that virus infection impacts L1 expression, potentially impacting host antiviral response and diseases. The underlying regulation mechanism is unclear. Epstein-Barr virus (EBV), a double-stranded DNA virus linked to B-cell and epithelial malignancies, is known to have viral-host genome interaction, resulting in transcriptional rewiring in EBV-associated gastric cancer (EBVaGC). By analyzing publicly available datasets from the Gene Expression Omnibus (GEO), we found that EBVaGC has L1 transcriptional repression compared with EBV-negative gastric cancer (EBVnGC). More specifically, retrotransposition-associated young and full-length L1s (FL-L1s) were among the most repressed L1s. Epigenetic alterations, especially increased H3K9me3, were observed on FL-L1s. H3K9me3 deposition was potentially attributed to increased TASOR expression, a key component of the human silencing hub (HUSH) complex for H3K9 trimethylation. The 4C- and HiC-seq data indicated that the viral DNA interacted in the proximity of the TASOR enhancer, strengthening the loop formation between the TASOR enhancer and its promoter. These results indicated that EBV infection is associated with increased H3K9me3 deposition, leading to L1 repression. This study uncovers a regulation mechanism of L1 expression by chromatin topology remodeling associated with viral-host genome interaction in EBVaGC.

Anxiety symptoms and health-related quality of life in mainland Chinese pregnant women: a cross-sectional study.

OBJECTIVE: Health-related quality of life allows the health care professionals to envisage new axes of improvement in antenatal care and is a core aspect of contemporary maternity care provision. This study aims to estimate the prevalence of anxiety symptoms and explore the relationship between anxiety symptoms and health-related quality of life among Chinese pregnant women. METHODS: A cross-sectional study was conducted in a local teaching hospital in Guangzhou, China between April and June, 2018. Seven hundred and seventy Chinese pregnant women completed the 36-Item Short-Form Health Survey (SF-36), the Self-rating Anxiety Scale (SAS) and socio-demographic questionnaires. RESULTS: 18.2% women were classified as having elevated anxiety symptoms as evidenced by a SAS score ≥50. Compared with women without anxiety symptoms, the pregnant women with anxiety symptoms had worse physical (SF36-PCS) and mental (SF36-MCS) health-related quality of life and a lower level of seven domains of SF-36 (GH, RP, BP, VT, SF, RE and MH). Elevated anxiety symptoms predicted worse physical (SF36-PCS) and mental (SF36-MCS) health-related quality of life. The third trimester predicted a lower level of physical (SF36-PCS) health-related quality of life, while an unsatisfied relationship with mother-in-law predicted a lower level of mental (SF36-MCS) health-related quality of life. CONCLUSIONS: The pregnant women with anxiety symptoms had impaired health-related quality of life. Health care professionals should identify pregnant women with anxiety symptoms and facilitate their treatment, which could improve their health-related quality of life.

Dynamic chromatin landscape encodes programs for perinatal transition of cardiomyocytes.

The perinatal period occurring immediately before and after birth is critical for cardiomyocytes because they must change rapidly to accommodate the switch from fetal to neonatal circulation after birth. This transition is a well-orchestrated process, and any perturbation leads to unhealthy cardiomyocytes and heart disease. Despite its importance, little is known about how this transition is regulated and controlled. Here, by mapping the genome-wide chromatin accessibility, transcription-centered long-range chromatin interactions and gene expression in cardiomyocytes undergoing perinatal transition, we discovered two key transcription factors, MEF2 and AP1, that are crucial for driving the phenotypic changes within the perinatal window. Thousands of dynamic regulatory elements were found in perinatal cardiomyocytes and we show these elements mediated the transcriptional reprogramming through an elegant chromatin high-order architecture. We recompiled transcriptional program of induced stem cell-derived cardiomyocytes according to our discovered network, and they showed adult cardiomyocyte-like electrophysiological expression. Our work provides a comprehensive regulatory resource of cardiomyocytes perinatal reprogramming, and aids the gap-filling of cardiac translational research.

Incidence and correlates of insomnia and its impact on health-related quality of life among Chinese pregnant women: a cross-sectional study.

OBJECTIVE: The aims of this study were to examine the incidence and correlates of insomnia and its impact on health-related quality of life among Chinese pregnant women. METHOD: A cross-sectional study was performed from November 2018 to April 2019 in a university-affiliated general hospital in Guangzhou, China. Seven hundred and seventeen pregnant women completed the 36-item Short-Form Health Survey (SF-36), the Self-Rating Anxiety Scale (SAS), the Self-Rating Depression Scale (SDS), and the obstetric and sociodemographic data sheet. FINDINGS: 24.3% of the pregnant women suffered from insomnia. Compared with women without insomnia, those with insomnia had a significantly lower health-related quality of life during pregnancy. Maternal age, educational level, occupation, economic status, insurance coverage, gestational age, the woman's relationship with her mother-in-law and anxiety were significantly associated with insomnia among pregnant women. CONCLUSION: The incidence of insomnia among pregnant women is high, and insomnia is negatively correlated with health-related quality of life. Appropriate measures and practical therapeutic programmes should be provided to prevent the adverse effects of insomnia in pregnant women with advanced maternal age, lower education, lower economic status, unemployment, lack of insurance coverage, unsatisfied with their relationships with their mothers-in-law, and suffering from anxiety symptoms, especially in the third trimester.

Effect of Repetitive Transcranial Magnetic Stimulation on the Nutritional Status and Neurological Function of Patients With Postischemic Stroke Dysphagia.

BACKGROUND: This project aimed to explore the effects of repetitive transcranial magnetic stimulation (rTMS) on the nutritional status and neurological function of patients with postischemic stroke dysphagia. MATERIALS AND METHODS: After recruiting 70 inpatients with cerebral infarction combined with dysphagia hospitalized in the Cerebrovascular Center of Guangdong Second Provincial General Hospital from June 2017 to June 2020, we assigned them randomly into a control group and an rTMS group. Patients in the control group received swallowing training, while patients of the rTMS group received swallowing training and rTMS. RESULTS: Fifteen days after treatment, serum nutrition indexes and neurotrophic indexes of both groups were higher than before treatment, and their serum nerve injury indexes were lower than before treatment. After 15 days of treatment, the body nutrition indexes and neuronutrition indexes of the rTMS group were higher than those of the control group, while the nerve injury indexes of the rTMS group were lower than those of the control group. CONCLUSION: rTMS in the treatment of dysphagia after stroke can better improve nutritional status and nerve function, reducing nerve damage.

Lpar1-mediated Effects in Endothelial Progenitor Cells Are Crucial for Lung Repair in Acute Respiratory Distress Syndrome/Acute Lung Injury.

Acute respiratory distress syndrome/acute lung injury (ARDS/ALI) involves acute respiratory failure characterized by vascular endothelial and lung alveolar epithelial injury. Endothelial progenitor cells (EPCs) can mediate vasculogenesis. However, the limitations of EPCs, such as low survival and differentiation, are believed to inhibit the effectiveness of autologous cell therapies. This study demonstrated that lysophosphatidic acid (LPA), a bioactive small molecule without immunogenicity, is involved in the survival and antiapoptotic effects in human umbilical cord mesenchymal stem cells. This study aimed to explore whether LPA improves the survival of EPCs, enhancing the cellular therapeutic efficacy in ARDS, and these results will expand the application of LPA in stem cells and regenerative medicine. LPA promoted the colony formation, proliferation, and migration of EPCs and upregulated the expression of vascular endothelial-derived growth factor (VEGF) in EPCs. LPA pretreatment of transplanted EPCs improved the therapeutic effect by increasing EPC numbers in the rat lungs. LPA enhanced EPC proliferation and migration through Lpar1 coupled to Gi/o and Gq/11, respectively. Activation of extracellular signal-related kinase 1/2, or ERK1/2, was related to LPA-induced EPC proliferation but not migration. LPA/Lpar1-mediated Gi/o protein was also shown to be involved in promoting VEGF expression and inhibiting IL-1α expression in EPCs. Low LPA concentrations are present after lung injury; thus, the restoration of LPA may promote endothelial cell homeostasis and lung repair in ARDS. Inhalation of LPA significantly promoted the homing of endogenous EPCs to the lung and reduced lung injury in both rats with LPS-induced ALI and Streptococcus pneumoniae-infected mice. Taken together, these data indicated that LPA/Lpar1-mediated effects in EPCs are involved in maintaining endothelial cell homeostasis and lung tissue repair under physiological conditions.

AL008 Enhances Myeloid Antitumor Function by Inhibiting SIRPα Signaling and Activating Fc Receptors.

Antagonizing the CD47-signal regulatory protein (SIRP)α pathway, a critical myeloid checkpoint, promotes antitumor immunity. In this study, we describe the development of AL008, a pan-allelic, SIRPα-specific Ab that triggers the degradation of SIRPα and, concurrently, stimulates FcγR activation of myeloid cells through an engineered Fc domain. AL008 showed superior enhancement of phagocytosis of tumor cells opsonized with antitumor Ag Abs compared with another SIRPα Ab tested. Unlike ligand-blocking SIRPα Abs, AL008 demonstrated single-agent activity by increasing tumor cell engulfment by human monocyte-derived macrophages even in the absence of opsonizing agents. This effect was due to enhanced Fc function, as blocking FcγR2A abrogated AL008-mediated phagocytic activity. AL008 also promoted human monocyte-derived dendritic cell-mediated T cell proliferation. In humanized mouse models, AL008 induced internalization of SIRPα and increased expression of CD86 and HLA-DR on human tumor-associated macrophages, confirming that the mechanism of action is retained in vivo. Monotherapy treatment with AL008 significantly reduced tumor growth in humanized mice implanted with human MDA-MB-231 tumor cells. AL008 also significantly potentiated the effects of T cell checkpoint blockade with anti-programmed death ligand-1 in syngeneic tumor models. This dual and specific mechanism of AL008, to our knowledge, provides a novel therapeutic strategy for targeting myeloid cells for immune activation.

Soil microbial community structure dynamics shape the rhizosphere priming effect patterns in the paddy soil.

Microbial community structure plays a crucial part in soil organic carbon (SOC) decomposition and variation of rhizosphere priming effects (RPEs) during plant growth. However, it is still uncertain how bacterial community structure regulates RPEs in soil and how RPE patterns respond to plant growth. Therefore, we conducted an experiment to examine the RPE response to plant growth and nitrogen (N) addition (0 (N0), 150 (N150), and 300 (N300) kg N ha-1) using the 13C natural abundance method in a C3 soil (paddy soil) - C4 plant (maize, Zea mays L.) system; we then explored the underlying biotic mechanisms using 16S rRNA sequencing techniques. Networks were constructed to identify keystone taxa and to analyze the correlations between network functional modules of bacterial community and C decomposition. The results indicated that negative and positive RPEs occurred on Day 30 and Day 75 after maize planting, respectively. Bacterial community structure significantly changed and tended to shift from r-strategists toward K-strategists with changing labile C: N stoichiometry and soil pH during plant growth stages. The different network modules of bacterial community were aggregated in response to RPE pattern variation. Caulobacteraceae, Bacillus, and Chitinophagaceae were keystone taxa on Day 30, while Gemmatimonas, Candidatus Koribacter, and Xanthobacteraceae were keystone taxa on Day 75. Moreover, keystone taxa with different C utilization strategies were significantly different between the two growth stages and related closely to different RPE patterns. This study provides deeper insights into the network structure of bacterial communities corresponding to RPE patterns and emphasizes the significance of keystone taxa in RPE variation.

A Longitudinal Study of Stress in New Nurses in their First Year of Employment.

Objective: This study aimed to analyze changes in occupational stress in new nurses during the first year of employment. Methods: A prospective longitudinal study was conducted from 2020 to 2021 using one questionnaire four times on 127 newly employed nurses in a tertiary general teaching hospital in the province of Fujian. Results: The results showed that new nurses had moderate to high levels of stress in all four stages, with the highest stress level at 4 and 8 months of employment and the lowest stress level at 12 months; the differences in stress scores at different time points were statistically significant (p < 0.05). The trends in each stressor dimension varied across different periods. The highest scores were for pressure caused by "time allocation and workload," which peaked in month 8. The same trend was observed for stress from "patient care" and "work environment and equipment." "Management and interpersonal relationships" scored the highest overall stress score at the start of employment before declining. The lowest stress score was from "work environment and equipment" at the start of employment, and the lowest was from "management and interpersonal relationships" from month 4 onward. Conclusion: New nurses had higher overall occupational stress during their first year of employment under different stressors. Therefore, nursing managers should actively focus on stress factors of new nurses and provide targeted interventions to help them during their training period.

Long-term survival analysis of patients with stage IIIB-IV non-small cell lung cancer complicated by type 2 diabetes mellitus: A retrospective propensity score matching analysis.

BACKGROUND: This study aimed to determine the effect of type 2 diabetes mellitus (T2DM) on overall survival (OS) of patients with stage IIIB-IV non-small cell lung cancer (NSCLC). METHODS: We retrospectively analyzed patients with stage IIIB-IV NSCLC from January 2015 to December 2018 in the Department of Oncology at the First Affiliated Hospital of Anhui University of Traditional Chinese Medicine. Kaplan-Meier plots, log-rank tests, and Cox proportional hazards regression models were used to describe the effect of T2DM on the OS of patients with stage IIIB-IV NSCLC. RESULTS: This study collected data on 76 patients with NSCLC and T2DM (group A) and 214 NSCLC patients without T2DM (group B). After propensity score matching (PSM) analysis, 74 patients were included in each group. The mean OS of all patients was 17 months (range, 11-31 months). The mean OS of group A was 15 months (range, 8-25 months) and the mean OS of group B was 20 months (range, 14-39 months). The mean OS of group B was longer than group A, and the difference was statistically significant. Univariate analysis of the clinical data showed that T2DM and complications were significantly correlated with the prognosis of patients with stage IIIB-IV NSCLC (p = 0.003 and p = 0.034). Multivariate Cox model analysis showed that T2DM and complications were independent prognostic factors for patients with stage IIIB-IV NSCLC (p = 0.002 and p = 0.024, respectively). CONCLUSION: Stage IIIB-IV NSCLC patients without T2DM have an increased OS compared to patients with stage IIIB-IV NSCLE and T2DM.

Analysis of the miRNA expression profile of laboratory red crucian carp under low-dose caesium-137 irradiation.

Radiation can cause the differential expression of biological miRNA molecules. This research was based on the development of the laboratory red crucian carp (LRCC) to explore the feasibility of its application in the detection of low-dose ionizing radiation-induced biological damage in aquatic environments and the development of related molecular markers. Adult LRCC were irradiated with caesium-137 at 0.3 Gy, while RNA-seq and bioinformatics techniques were used to identify miRNAs that were differentially expressed relative to their levels in the nonirradiation group. Analysis of liver sections showed that liver cells in the radiation group showed nuclear pyknosis. In this study, 34 miRNAs differentially expressed in the liver of LRCC after irradiation were identified, among which seven were new crucian carp miRNAs; a total of 632 target genes were predicted in the prediction analysis. The results of comprehensive GO enrichment and KEGG pathway analyses showed that these target genes were mainly involved in energy transfer and material catabolism, especially malonyl-CoA biosynthesis, acetyl-CoA carboxylase activity, fatty acid biosynthesis and metabolism, and pyruvate metabolism; in addition, the AMPK signalling pathway was the most active pathway. This study shows that the LRCC is sensitive to radiation, or can be used as a candidate experimental animal to study the biological effects of radiation, and the screened miRNA can be used as a pre-selected biomarker for radiation damage detection and radiation biological environmental monitoring. CLINICAL TRIALS REGISTRATION: None.

MicroRNAs combined with the TLR4/TDAG8 mRNAs and proinflammatory cytokines are biomarkers for the rapid diagnosis of sepsis.

The early diagnosis and treatment of sepsis are of particular importance to patient survival. To obtain novel biomarkers that serve as prompt indicators of sepsis, the current study screened the differentially expressed microRNAs (DEMs) that were associated with sepsis susceptibility. The correlation between the elucidated DEMs and the inflammatory response was also examined. The present study included 40 patients with sepsis and 40 healthy controls. RNA­sequencing technology and bioinformatics analysis were applied to screen the DEMs between the two cohorts. The expression of these DEMs was subsequently verified by performing reverse transcription­quantitative PCR (RT­qPCR). In addition, IL­6, IL­21, C­X­C motif chemokine ligand­8 (CXCL8) and monocyte chemoattractant protein­1 (MCP­1) levels, along with T­cell death­associated gene 8 (TDAG8) and toll­like receptor 4 (TLR4) mRNA expression levels were assessed. The association between microRNA (miRNA/miR)­3663­3p and the secretion of various proinflammatory cytokines or TDAG8 and TLR4 mRNA expressions were subsequently evaluated by linear correlation analysis. The results revealed 305 DEMs (P<0.05; fold change >2) between patients with sepsis and healthy controls. Among these, the top 18 up­ and downregulated miRNAs were selected for RT­qPCR verification. In addition, the serum content of IL­6, IL­21, CXCL8 and MCP­1, and the expression of TDAG8 and TLR4 mRNAs were significantly increased in patients with sepsis compared with healthy controls. Moreover, in patients with sepsis, a positive correlation was identified between miR­3663­3p and the secretion of inflammatory cytokines or TDAG8 and TLR4 mRNA expression. A positive correlation was also elucidated between TDAG8 and TLR4 mRNA expression and proinflammatory cytokine/chemokine secretion. Receiver operating characteristic curve analysis of miR­3663­3p expression, IL­6, IL­21, CXCL8 and MCP­1 secretion and TDAG8 and TLR4 mRNA expression demonstrated that miRNA analysis may be invaluable for the diagnosis of sepsis. Collectively, the results determined that miR­3663­3p may be a potentially powerful diagnostic and predictive biomarker of sepsis and that the combined and simultaneous detection of several biomarkers, including proteins, miRNAs and mRNA may be a reliable approach for the fast diagnosis and early identification of sepsis.

Adipose­derived mesenchymal stem cell­derived HCAR1 regulates immune response in the attenuation of sepsis.

Sepsis serves as a leading cause of admission to and death of patients in the intensive care unit (ICU) and is described as a systemic inflammatory response syndrome caused by abnormal host response to infection. Adipose­derived mesenchymal stem cells (ADSCs) have exhibited reliable and promising clinical application potential in multiple disorders. However, the function and the mechanism of ADSCs in sepsis remain elusive. In the present study, the crucial inhibitory effect of ADSC­derived hydroxy­carboxylic acid receptor 1 (HCAR1) on sepsis was identified. Reverse transcription quantitative­PCR determined that the mRNA expression of HCAR1 was reduced while the mRNA expression of Toll­like receptor 4 (TLR4), major histocompatibility complex class II (MHC II), NOD­like receptor family pyrin domain containing 3 (NLRP3), and the levels of interleukin­1ß (IL­1ß), tumor necrosis factor­α (TNF­α), interleukin­10 (IL­10), and interleukin­18 (IL­18) were enhanced in the peripheral blood of patients with sepsis. The expression of HCAR1 was negatively correlated with TLR4 (r=­0.666), MHC II (r=­0.587), and NLRP3 (r=­0.621) expression and the expression of TLR4 was positively correlated with NLRP3 (r=0.641), IL­1ß (r=0.666), TNF­α (r=0.606), and IL­18 (r=0.624) levels in the samples. Receiver operating characteristic (ROC) curve analysis revealed that the area under the ROC curve (AUC) of HCAR1, TLR4, MHC II and NLRP3 mRNA expression was 0.830, 0.853, 0.735 and 0.945, respectively, in which NLRP3 exhibited the highest diagnostic value, and the AUC values of IL­1ß, IL­18, TNF­α, and IL­10 were 0.751, 0.841, 0.924 and 0.729, respectively, in which TNF­α exhibited the highest diagnostic value. A sepsis rat model was established by injecting lipopolysaccharide (LPS) and the rats were randomly divided into 5 groups, including a normal control group (NC group; n=6), a sepsis model group (LPS group; n=6), an ADSC transplantation group (L + M group; n=6), a combined HCAR1 receptor agonist group [L + HCAR1 inducer (Gi) + M group; n=6], and a combined HCAR1 receptor inhibitor group [L + HCAR1 blocker (Gk) + M group; n=6]. Hematoxylin and eosin staining determined that ADSCs attenuated the lung injury of septic rats and ADSC­derived HCAR1 enhanced the effect of ADSCs. The expression of HCAR1, TLR4, MHC II, NLRP3, IL­1ß, IL­18 and TNF­α levels were suppressed by ADSCs and the effect was further induced by ADSC­derived HCAR1. However, ADSC­derived HCAR1 induced the levels of anti­inflammatory factor IL­10. The negative correlation of HCAR1 expression with TLR4, MHC II, and NLRP3 expression in the peripheral blood and lung tissues of the rats was then identified. It is thus concluded that ADSC­derived HCAR1 regulates immune response in the attenuation of sepsis. ADSC­derived HCAR1 may be a promising therapeutic strategy for sepsis.

HMGB1 Upregulates RAGE to Trigger the Expression of Inflammatory Factors in the Lung Tissue in a Hypoxic Pulmonary Hypertension Rat Model.

Hypoxic pulmonary hypertension (HPH), a form of pulmonary hypertension (PH) caused by hypoxia, could cause serious complications and has a high mortality rate, and no clinically effective treatments are currently available. In this study, we established an HPH preclinical model in rats by simulating clinicopathological indicators of the disease. Our results showed that high mobility group box-1 protein (HMGB1) aggravated the clinical symptoms of HPH. We aimed at establishing protocols and ideas for the clinical treatment of HPH by identifying downstream HMGB1 binding receptors. Our investigation showed that continuous hypoxia could cause significant lung injury in rats. ELISA and western blotting experiments revealed that HPH induces inflammation in the lung tissue and increases the expression of a hypoxia-inducible factor. Testing of lung tissue proteins in vivo and in human pulmonary artery endothelial cells in vitro revealed that the HMGB1-mediated increase in the receptor for advanced glycation end products (RAGE) expression promoted inflammation. In summary, we successfully established an HPH rat model providing a new model for preclinical HPH research and elucidated the role of HMGB1 in HPH. Furthermore, we describe that HMGB1 induced inflammation in the HPH model via RAGE, causing severe lung dysfunction. This study could potentially provide novel ideas and methods for the clinical treatment of HPH.

Single-cell chromatin accessibility landscape in kidney identifies additional cell-of-origin in heterogenous papillary renal cell carcinoma.

Papillary renal cell carcinoma (pRCC) is the most heterogenous renal cell carcinoma. Patient survival varies and no effective therapies for advanced pRCC exist. Histological and molecular characterization studies have highlighted the heterogeneity of pRCC tumours. Recent studies identified the proximal tubule (PT) cell as a cell-of-origin for pRCC. However, it remains elusive whether other pRCC subtypes have different cell-of-origin. Here, by obtaining genome-wide chromatin accessibility profiles of normal human kidney cells using single-cell transposase-accessible chromatin-sequencing and comparing the profiles with pRCC samples, we discover that besides PT cells, pRCC can also originate from kidney collecting duct principal cells. We show pRCCs with different cell-of-origin exhibit different molecular characteristics and clinical behaviors. Further, metabolic reprogramming appears to mediate the progression of pRCC to the advanced state. Here, our results suggest that determining cell-of-origin and monitoring origin-dependent metabolism could potentially be useful for early diagnosis and treatment of pRCC.

Effect of Src tyrosine kinase on a rat model of asthma.

Src tyrosine kinase is a protein encoded by the Src gene. The present study aimed to determine the role of Src protein kinase in asthma using small interfering RNA (siRNA) technology. Several Src siRNAs were designed and the most effective siRNA pair was selected. A rat model of asthma was established using ovalbumin, and the rats were treated with Src siRNA, empty vector or phosphate-buffered saline (PBS). A non-asthmatic control group was also established. The rats were clinically observed and Src mRNA and protein levels were measured by reverse transcription-quantitative PCR and western blot analysis, respectively. Pathological observation of the lung tissue, counting of white blood cells (WBCs) and eosinophils (EOSs) and analysis of the concentrations of IL-5, IL-33 and IFN-γ in the bronchoalveolar lavage fluid were performed. The expression levels of Src mRNA in the control, PBS, empty vector and siRNA groups were 110±30.7x103, 253±55.4x103, 254±41.3x103 and 180±50.9x103, respectively. Histochemical analysis of the lung tissue of rats in the siRNA group exhibited a relatively complete lung structure and little damage to the alveolar cavity. Src protein expression and IL-5, IL-33 levels, WBC and EOS levels were positively correlated with Src mRNA expression, while the IFN-γ concentration was negatively correlated with Src mRNA expression. These results indicate that Src knockdown inhibits the release of tracheal inflammatory factors and significantly alleviates asthma in rats. In conclusion, the present study utilized a gene transfer technique to interfere with the expression of Src in rats, which decreased the levels of IL-5, IL-33, WBCs and EOSs and increased the level of IFN-γ; these changes effectively ameliorated the condition of the trachea in asthmatic rats.