Peripheral inflammation and trajectories of depressive symptomology after ischemic stroke: A prospective cohort study.

BACKGROUND: Understanding the association of peripheral inflammation and post-stroke depressive symptomology (PSDS) might provide further insights into the complex etiological mechanism of organic depression. However, studies focusing on the longitudinal patterns of PSDS were limited and it remained unclear whether peripheral inflammation influences the occurrence and development of PSDS. METHODS: A total of 427 prospectively enrolled and followed ischemic stroke patients were included in the analytical sample. Depressive symptomology was assessed on four occasions during 1 year after ischemic stroke. Peripheral inflammatory proteins on admission and repeated measures of peripheral immune markers in three stages were collected. Latent class growth analysis (LCGA) was employed to delineate group-based trajectories of peripheral immune markers and PSDS. Multinomial regression was performed to investigate the association of peripheral inflammation with PSDS trajectories. RESULTS: Four distinct trajectories of PSDS were identified: stable-low (n = 237, 55.5 %), high-remitting (n = 120, 28.1 %), late-onset (n = 44, 10.3 %), and high-persistent (n = 26, 6.1 %) PSDS trajectories. The elevation of peripheral fibrinogen on admission increased the risk of high-persistent PSDS in patients with early high PSDS. Additionally, chronic elevation of innate immune levels might not only increase the risk of high-persistent PSDS in patients with early high PSDS but also increase the risk of late-onset PSDS in patients without early high PSDS. The elevation of adaptive immune levels in the convalescence of ischemic stroke may contribute to the remission of early high PSDS. CONCLUSIONS: Peripheral immunity could influence the development of PSDS, and this influence might have temporal heterogeneity. These results might provide vital clues for the inflammation hypothesis of PSD.

L-arginine attenuates Streptococcus uberis-induced inflammation by decreasing miR155 level.

L-arginine, as an essential substance of the immune system, plays a vital role in innate immunity. MiR155, a multi-functional microRNA, has gained importance as a regulator of homeostasis in immune cells. However, the immunoregulatory mechanism between L-arginine and miR155 in bacterial infections is unknown. Here, we investigated the potential role of miR155 in inflammation and the molecular regulatory mechanisms of L-arginine in Streptococcus uberis (S. uberis) infections. And we observed that miR155 was up-regulated after infection, accompanying the depletion of L-arginine, leading to metabolic disorders of amino acids and severe tissue damage. Mechanically, the upregulated miR155 mediated by the p65 protein played a pro-inflammatory role by suppressing the suppressor of cytokine signaling 6 (SOCS6)-mediated p65 ubiquitination and degradation. This culminated in a violently inflammatory response and tissue damage. Interestingly, a significant anti-inflammatory effect was revealed in L-arginine supplementation by reducing miR155 production via inhibiting p65. This work firstly uncovers the pro-inflammatory role of miR155 and an anti-inflammatory mechanism of L-arginine in S.uberis infection with a mouse mastitis model. Collectively, we provide new insights and strategies for the prevention and control of this important pathogen, which is of great significance for ensuring human food health and safety.

A critical role for host-derived cystathionine-ß-synthase in Staphylococcus aureus-induced udder infection.

Cystathionine-ß-synthase (CBS) catalyzes the first step of the transsulfuration pathway. The role of host-derived CBS in Staphylococcus aureus (S. aureus)-induced udder infection remains elusive. Herein, we report that S. aureus infection enhances the expression of CBS in mammary epithelial cells in vitro and in vivo. A negative correlation is present between the expression of CBS and inflammation after employing a pharmacological inhibitor/agonist of CBS. In addition, CBS achieves a fine balance between eliciting sufficient protective innate immunity and preventing excessive damage to cells and tissues preserving the integrity of the blood-milk barrier (BMB). CBS/H2S reduces bacterial load by promoting the generation of antibacterial substances (ROS, RNS) and inhibiting apoptosis, as opposed to relying solely on intense inflammatory reactions. Conversely, H2S donor alleviate inflammation via S-sulfhydrating HuR. Finally, CBS/H2S promotes the expression of Abcb1b, which in turn strengthens the integrity of the BMB. The study described herein demonstrates the importance of CBS in regulating the mammary immune response to S. aureus. Increased CBS in udder tissue modulates excessive inflammation, which suggests a novel target for drug development in the battle against S. aureus and other infections.

PFKFB3-Meditated Glycolysis via the Reactive Oxygen Species-Hypoxic Inducible Factor 1α Axis Contributes to Inflammation and Proliferation of Staphylococcus aureus in Epithelial Cells.

Mastitis caused by antibiotic-resistant strains of Staphylococcus aureus is a significant concern in the livestock industry due to the economic losses it incurs. Regulating immunometabolism has emerged as a promising approach for preventing bacterial inflammation. To investigate the possibility of alleviating inflammation caused by S aureus infection by regulating host glycolysis, we subjected the murine mammary epithelial cell line (EpH4-Ev) to S aureus challenge. Our study revealed that S aureus can colonize EpH4-Ev cells and promote inflammation through hypoxic inducible factor 1α (HIF1α)-driven glycolysis. Notably, the activation of HIF1α was found to be dependent on the production of reactive oxygen species (ROS). By inhibiting PFKFB3, a key regulator in the host glycolytic pathway, we successfully modulated HIF1α-triggered metabolic reprogramming by reducing ROS production in S aureus-induced mastitis. Our findings suggest that there is a high potential for the development of novel anti-inflammatory therapies that safely inhibit the glycolytic rate-limiting enzyme PFKFB3.

Predicting ICU readmission risks in intracerebral hemorrhage patients: Insights from machine learning models using MIMIC databases.

BACKGROUND: Intracerebral hemorrhage (ICH) is a stroke subtype characterized by high mortality and complex post-event complications. Research has extensively covered the acute phase of ICH; however, ICU readmission determinants remain less explored. Utilizing the MIMIC-III and MIMIC-IV databases, this investigation develops machine learning (ML) models to anticipate ICU readmissions in ICH patients. METHODS: Retrospective data from 2242 ICH patients were evaluated using ICD-9 codes. Recursive feature elimination with cross-validation (RFECV) discerned significant predictors of ICU readmissions. Four ML models-AdaBoost, RandomForest, LightGBM, and XGBoost-underwent development and rigorous validation. SHapley Additive exPlanations (SHAP) elucidated the effect of distinct features on model outcomes. RESULTS: ICU readmission rates were 9.6% for MIMIC-III and 10.6% for MIMIC-IV. The LightGBM model, with an AUC of 0.736 (95% CI: 0.668-0.801), surpassed other models in validation datasets. SHAP analysis revealed hydrocephalus, sex, neutrophils, Glasgow Coma Scale (GCS), specific oxygen saturation (SpO2) levels, and creatinine as significant predictors of readmission. CONCLUSION: The LightGBM model demonstrates considerable potential in predicting ICU readmissions for ICH patients, highlighting the importance of certain clinical predictors. This research contributes to optimizing patient care and ICU resource management. Further prospective studies are warranted to corroborate and enhance these predictive insights for clinical utilization.

Taurine reduction of injury from neutrophil infiltration ameliorates Streptococcus uberis-induced mastitis.

Mastitis is a common disease of dairy cows characterized by infiltration of leukocytes, especially neutrophils, resulting in increased permeability of the blood-milk barrier (BMB). Taurine, a functional nutrient, has been shown to have anti-inflammatory and antioxidant effects. Here, we investigated the regulatory effects and mechanisms of taurine on the complex immune network of the mammary gland in Streptococcus uberis (S. uberis) infection. We found that taurine had no direct effect on CXCL2-mediated neutrophil chemotaxis. However, it inhibited MAPK and NF-κB signalings by modulating the activity of TAK1 downstream of TLR2, thereby reducing CXCL2 expression in macrophages to reduce neutrophil recruitment in S. uberis infection. Further, the AMPK/Nrf2 signaling pathway was activated by taurine to help mitigate oxidative damage, apoptosis and disruption of tight junctions in mammary epithelial cells caused by hypochlorous acid, a strong oxidant produced by neutrophils, thus protecting the integrity of the mammary epithelial barrier. Taurine protects the BMB from damage caused by neutrophils via blocking the macrophage-CXCL2-neutrophil signaling axis and increasing the antioxidant capacity of mammary epithelial cells.

Mitochondrial dysfunction: A fatal blow in depression.

Mitochondria maintain the normal physiological function of nerve cells by producing sufficient cellular energy and performing crucial roles in maintaining the metabolic balance through intracellular Ca2+ homeostasis, oxidative stress, and axonal development. Depression is a prevalent psychiatric disorder with an unclear pathophysiology. Damage to the hippocampal neurons is a key component of the plasticity regulation of synapses and plays a critical role in the mechanism of depression. There is evidence suggesting that mitochondrial dysfunction is associated with synaptic impairment. The maintenance of mitochondrial homeostasis includes quantitative maintenance and quality control of mitochondria. Mitochondrial biogenesis produces new and healthy mitochondria, and mitochondrial dynamics cooperates with mitophagy to remove damaged mitochondria. These processes maintain mitochondrial population stability and exert neuroprotective effects against early depression. In contrast, mitochondrial dysfunction is observed in various brain regions of patients with major depressive disorders. The accumulation of defective mitochondria accelerates cellular nerve dysfunction. In addition, impaired mitochondria aggravate alterations in the brain microenvironment, promoting neuroinflammation and energy depletion, thereby exacerbating the development of depression. This review summarizes the influence of mitochondrial dysfunction and the underlying molecular pathways on the pathogenesis of depression. Additionally, we discuss the maintenance of mitochondrial homeostasis as a potential therapeutic strategy for depression.

Longitudinal relationships between depressive symptoms and cognitive function after stroke: A cross-lagged panel design.

OBJECTIVE: Stroke is a leading cause of mortality and disability. This study aimed to investigate the temporal and directional relationships between post-stroke depressive symptoms and cognitive impairment using a cross-lagged panel design. Depressive symptoms and cognitive impairment are two common post-stroke complications. However, the precise underlying mechanism remains unclear despite their close relationship. Therefore, elucidating the causal relationship between these two issues is of great clinical significance for improving the poor prognosis of stroke. METHODS: This study employed a hospital-based multicenter prospective cohort design. A total of 610 patients with ischemic stroke were eligible. Depressive symptoms (measured using the seventeen-item Hamilton Rating Scale for Depression) and cognitive function (measured using the Montreal Cognitive Assessment) were assessed at baseline and the 12-month follow-up. Spearman's correlation was used to examine the correlation between cognitive function and depressive symptoms. Additionally, a cross-lagged panel analysis was employed to elucidate the causal relationship between these factors after adjusting for potential covariates. RESULTS: The results of a four-iteration cross-lagged panel analysis substantiated a bidirectional relationship between post-stroke depressive symptoms and cognitive function over time. Specifically, higher scores for early depressive symptoms were associated with lower scores for later cognitive function; additionally, higher baseline cognitive function scores were associated with lower depressive symptom scores at a later point. CONCLUSION: This study establishes a reciprocally causal long-term relationship between depressive symptoms and cognitive function after an ischemic stroke. Therefore, interventions aimed at improving cognitive function and ameliorating depressive symptoms may positively affect both cognition and mood. TRIAL REGISTRATION: ChiCTR-ROC-17013993.

The therapeutic potential for targeting CSE/H2S signaling in macrophages against Escherichia coli infection.

Macrophages play a pivotal role in the inflammatory response to the zoonotic pathogen E. coli, responsible for causing enteric infections. While considerable research has been conducted to comprehend the pathogenesis of this disease, scant attention devoted to host-derived H2S. Herein, we reported that E. coli infection enhanced the expression of CSE in macrophages, accompanied by a significantly increased inflammatory response. This process may be mediated by the involvement of excessive autophagy. Inhibition of AMPK or autophagy with pharmacological inhibitors could alleviate the inflammation. Additionally, cell model showed that the mRNA expression of classic inflammatory factors (Il-1ß, Il-6), macrophage polarization markers (iNOS, Arg1) and ROS production was significantly down-regulated after employing CSE specific inhibitor PAG. And PAG is capable of inhibiting excessive autophagy through the LKB1-AMPK-ULK1 axis. Interestingly, exogenous H2S could suppress inflammation response. Our study emphasizes the importance of CSE in regulating the macrophage-mediated response to E. coli. Increased CSE in macrophages leads to excessive inflammation, which should be considered a new target for drug development to treat intestinal infection.

Smartphone-based pH responsive 3-channel colorimetric biosensor for non-enzymatic multi-antibiotic residues.

Antibiotic residues in animal-derived food pose a risk to food safety and human health. Here, a smartphone-based pH-responsive 3-channel colorimetric biosensor is constructed for rapid detection of non-enzymatic multi-antibiotic residues in milk. In this system, a magnetic separation and enrichment approach is designed to specifically capture different antibiotic residues in complex environment. Indicators loaded on polydopamine-silver nanoparticles with excellently pH responsive visualization properties are utilized to ensure the high sensitivity of detection system. Moreover, smartphones are introduced to fulfill the demand for portable and on-site inspection of practical applications. It achieves simultaneous detection of oxytetracycline, kanamycin and streptomycin in the linear range of 1-105 pg/mL with detection limits of 0.085, 0.168, and 0.307 pg/mL, respectively. The practicality of the reported multi-antibiotic residues detection system is successfully demonstrated and evaluated challenging milk samples. Therefore, this system demonstrates the wide applications in multi-antibiotic residue analysis and food safety guarantee.

Electrochemical detection of SARS-CoV-2 based on copper nanoflower-triggered in situ growth of electroactive polymers.

SARS-CoV-2, the pathogen of COVID-19, has introduced massive confirmed cases and millions of deaths worldwide, which poses a serious public health threat. For the early diagnosis of COVID-19, we have constructed an electrochemical biosensor-combined magnetic separation system with copper nanoflower-triggered cascade signal amplification strategy. In the proposed system, magnetic beads were utilized to fabricate the recognition element for capturing the conserved sequence of SARS-CoV-2. As the copper ions source, oligonucleotides modified copper nanoflowers with special layered structure provide numerous catalysts for click chemistry reaction. When target sequence RdRP_SARSr-P2 appears, copper nanoflowers will be bound with magnetic beads, thus prompting the Cu(I)-catalyzed azide-alkyne cycloaddition reaction through the connection of the SARS-CoV-2 conserved sequence. Then, a large number of signal molecules FMMA can be grafted onto the modified electrode surface by electrochemically mediated atom-transfer radical polymerization to amplify the signal for the quantitative analysis of SARS-CoV-2. Under optimal conditions, a linear range from 0.1 to 103 nM with a detection limit of 33.83 pM is obtained. It provides a powerful tool for the diagnosis of COVID-19, which further benefits the early monitoring of other explosive infectious diseases effectively, thus guaranteeing public health safety.

Depressive symptom dimensions predict the treatment effect of repetitive transcranial magnetic stimulation for post-stroke depression.

OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) has attracted considerable attention because of its non-invasiveness, minimal side effects, and treatment efficacy. Despite an adequate duration of rTMS treatment, some patients with post-stroke depression (PSD) do not achieve full symptom response or remission. METHODS: This was a prospective randomized controlled trial. Participants receiving rTMS were randomly assigned to the ventromedial prefrontal cortex (VMPFC), left dorsolateral prefrontal cortex (DLPFC), or contralateral motor area (M1) groups in a ratio of 1:1:1. Enrollment assessments and data collection were performed in weeks 0, 2, 4, and 8. The impact of depressive symptom dimensions on treatment outcomes were tested using a linear mixed-effects model fitted with maximum likelihood. Univariate analysis of variance (ANOVA) and back-testing were used to analyze the differences between the groups. RESULTS: In total, 276 patients were included in the analysis. Comparisons across groups showed that 17-item Hamilton Rating Scale for Depression (HAMD-17) scores of the DLPFC group significantly differed from those of the VMPFC and M1 groups at 2, 4, and 8 weeks after treatment (p < 0.05). A higher observed mood score (ß = -0.44, 95% confidence interval [CI]: -0.85-0.04, p = 0.030) could predict a greater improvement in depressive symptoms in the DLPFC group. Higher neurovegetative scores (ß = 0.60, 95% CI: 0.25-0.96, p = 0.001) could predict less improvement of depressive symptoms in the DLPFC group. CONCLUSION: Stimulation of the left DLPFC by high-frequency rTMS (HF-rTMS) could significantly improve depressive symptoms in the subacute period of subcortical ischemic stroke, and the dimension of depressive symptoms at admission might predict the treatment effect.

Prognostic and immunological role of FDX1 in pan-cancer: an in-silico analysis.

Previous research has demonstrated that ferredoxin 1 (FDX1) contributes to the accumulation of toxic lipoylated dihydrolipoamide S-acetyltransferase (DLAT) and results in cuproptotic cell death. However, the role that FDX1 plays in human cancer prognosis and immunology is still not well understood. The original data was obtained from TCGA and GEO databases and integrated using R 4.1.0. The TIMER2.0, GEPIA, and BioGPS databases were used to explore FDX1 expression. The impact of FDX1 on prognosis was analyzed using the GEPIA and Kaplan-Meier Plotter databases. External validation will be performed using the PrognoScan database. FDX1 expression in different immune and molecular subtypes of human cancers was evaluated using the TISIDB database. The correlation between FDX1 expression and immune checkpoints (ICP), microsatellite instability (MSI), and tumor mutational burden (TMB) in human cancers was analyzed using R 4.1.0. The TIMER2.0 and GEPIA databases were used to study the relationship between FDX1 expression and tumor-infiltrating immune cells. With the c-BioPortal database, we investigated the genomic alterations of FDX1. Pathway analysis and assessment of the sensitivity potential of FDX1-related drugs were also performed. Using the UALCAN database, we analyzed the differential expression of FDX1 in KIRC (kidney renal clear cell carcinoma) with different clinical features. Coexpression networks of FDX1 were analyzed using LinkedOmics. In general, FDX1 was expressed differently in different types of cancer in humans. Expression of FDX1 was strongly correlated with patient prognosis, ICP, MSI, and TMB. FDX1 was also participated in immune regulation and the tumor microenvironment. Coexpression networks of FDX1 were primarily involved in oxidative phosphorylation regulation. Pathway analysis revealed that the expression of FDX1 was correlated to cancer-related and immune-related pathways. FDX1 has the potential to serve as a biomarker for pan-cancer prognosis and immunology, as well as a novel target for tumor therapy.

Incremental Value of Stroke-Induced Structural Disconnection in Predicting Global Cognitive Impairment After Stroke.

BACKGROUND: Poststroke cognitive impairment (PSCI) is highly prevalent in stroke survivors and correlated with unfavorable clinical outcomes. This study aimed to identify the neural substrate of PSCI using atlas-based disconnectome analysis and assess the value of disconnection score, a baseline measure for stroke-induced structural disconnection, in PSCI prediction. METHODS: A multicenter prospective cohort of 676 first-ever patients with acute ischemic stroke was enrolled from 3 independent hospitals in China. Sociodemographic, clinical, and neuroimaging data were collected at acute stage of stroke. Cognitive assessment was performed at 3 months after stroke. Voxel-wise and tract-wise disconnectome analysis were performed to uncover the strategic structural disconnection pattern for global PSCI. Disconnection score was calculated for each participant in leave-one-dataset-out cross-validation. Multivariable logistic regression was performed for the association between disconnection score and PSCI. Prediction models with and without disconnection score were developed, cross-validated, and compared in terms of discrimination and goodness-of-fit. RESULTS: Compared with lesions of non-PSCI, those of PSCI were more likely to have fiber connections with left prefrontal cortex and left deep structures (thalamus and basal ganglia). Disconnection score could predict the risk and severity of PSCI during cross-validation, and was independently associated with PSCI after controlling for all baseline covariates (odds ratio, 1.38 [95% CI, 1.17-1.64]; P<0.001). Incorporating disconnection score into a reference model with 6 known predictors resulted in significant improvement in both discrimination and goodness-of-fit throughout cross-validation. CONCLUSIONS: A strategic structural disconnection pattern centered on left prefrontal cortex, thalamus, and basal ganglia is identified for global PSCI using indirect disconnectome analysis. The baseline disconnection score is independently predictive of PSCI and has significant incremental value to preexisting sociodemographic, clinical, and neuroimaging predictors. REGISTRATION: URL: http://www.chictr.org.cn/enIndex.aspx; Unique identifier: ChiCTR-ROC-17013993.

Nomogram including indirect bilirubin for the prediction of post-stroke depression at 3 months after mild acute ischemic stroke onset.

Background: Post-stroke depression (PSD) has been proven to be associated with stroke severity. Thus, we hypothesized that the prevalence of PSD would be lower in patients with mild stroke. We aim to explore predictors of depression at 3 months after mild acute ischemic stroke (MAIS) onset and to develop a practical and convenient prediction model for the early identification of patients at high risk. Methods: A total of 519 patients with MAIS were consecutively recruited from three hospitals in Wuhan city, Hubei province. MAIS was defined as a National Institute of Health Stroke Scale (NIHSS) score of ≤5 at admission. Meeting the DSM-V diagnostic criteria and a 17-item Hamilton Rating Scale for Depression (HAMD-17) score of >7 at their 3-month follow-up were considered the primary outcomes. A multivariable logistic regression model was used to determine the factors adjusted for potential confounders, and all independent predictors were brought into the construction of a nomogram to predict PSD. Results: The prevalence of PSD is up to 32% at 3 months after MAIS onset. After adjusting for potential confounders, indirect bilirubin (p = 0.029), physical activity (p = 0.001), smoking (p = 0.025), hospitalization days (p = 0.014), neuroticism (p < 0.001), and MMSE (p < 0.001) remained independently and significantly related with PSD. The concordance index (C-index) of the nomogram jointly constructed by the aforementioned six factors was 0.723 (95% CI: 0.678-0.768). Conclusion: The prevalence of PSD seems equally high even if the ischemic stroke is mild, which calls for great concern from clinicians. In addition, our study found that a higher level of indirect bilirubin can lower the risk of PSD. This finding may provide a potential new approach to PSD treatment. Furthermore, the nomogram including bilirubin is convenient and practical to predict PSD after MAIS onset.

Psychopathological network for early-onset post-stroke depression symptoms.

BACKGROUND: Post-stroke depression (PSD) can be conceptualized as a complex network where PSD symptoms (PSDS) interact with each other. The neural mechanism of PSD and interactions among PSDS remain to be elucidated. This study aimed to investigate the neuroanatomical substrates of, as well as the interactions between, individual PSDS to better understand the pathogenesis of early-onset PSD. METHODS: A total of 861 first-ever stroke patients admitted within 7 days poststroke were consecutively recruited from three independent hospitals in China. Sociodemographic, clinical and neuroimaging data were collected upon admission. PSDS assessment with Hamilton Depression Rating Scale was performed at 2 weeks after stroke. Thirteen PSDS were included to develop a psychopathological network in which central symptoms (i.e. symptoms most strongly correlated with other PSDS) were identified. Voxel-based lesion-symptom mapping (VLSM) was performed to uncover the lesion locations associated with overall PSDS severity and severities of individual PSDS, in order to test the hypothesis that strategic lesion locations for central symptoms could significantly contribute to higher overall PSDS severity. RESULTS: Depressed mood, Psychiatric anxiety and Loss of interest in work and activities were identified as central PSDS at the early stage of stroke in our relatively stable PSDS network. Lesions in bilateral (especially the right) basal ganglia and capsular regions were found significantly associated with higher overall PSDS severity. Most of the above regions were also correlated with higher severities of 3 central PSDS. The other 10 PSDS could not be mapped to any certain brain region. CONCLUSIONS: There are stable interactions among early-onset PSDS with Depressed mood, Psychiatric anxiety and Loss of interest as central symptoms. The strategic lesion locations for central symptoms may indirectly induce other PSDS via the symptom network, resulting in higher overall PSDS severity. TRIAL REGISTRATION: URL: http://www.chictr.org.cn/enIndex.aspx ; Unique identifier: ChiCTR-ROC-17013993.

Application of Chlorogenic acid as a substitute for antibiotics in Multidrug-resistant Escherichia coli-induced mastitis.

Mastitis affects animal welfare and causes economic losses in the dairy industry. It is caused mainly by bacterial pathogens, among which Escherichia coli (E. coli) is one of the prominent causative agents. To treat bovine mastitis, antibiotics were widely used. However, their extensive and uncontrolled use has led to the emergence of multi-antibiotic-resistant strains. Indeed, a superbug of E. coli was successfully isolated from a mastitis-suffering cow and found resistant to at least 10 antibiotics. Therefore, the development of a universal therapeutic agent used as a replacement for the antibiotic is an immediate need in the dairy industry. To do so, we examined whether chlorogenic acid (CGA), a natural and herbal extract, could be a perfect alternative in mastitis treatment. In this study, we observed that the combination of CGA and antibiotic had an additive or synergistic effect; CGA fought against the superbug by directly targeting bacterial cell wall and membrane; CGA can significantly alleviate the mastitis caused by the superbug E. coli via its antimicrobial, antioxidant and anti-inflammatory activities. Collectively, these data indicated that CGA had a true potential to replace antibiotics during mastitis treatment.

AMPK/Drp1 pathway mediates Streptococcus uberis-Induced mitochondrial dysfunction.

Excessive production of reactive oxygen species (ROS) leads to oxidative stress in host cells and affects the progress of disease. Mitochondria are an important source of ROS and their dysfunction is closely related to ROS production. S. uberis is a common causative agent of mastitis. The expression of key enzymes of the mitochondrial apoptotic pathway is increased in mammary epithelial cells after S. uberis stimulation, while expression of proteins related to mitochondrial function is decreased. Drp1, a key protein associated with mitochondrial function, is activated upon infection. Accompanied by mitochondria-cytosol translocation of Drp1, Fis1 expression is significantly upregulated while Mfn1 expression is downregulated implying that the balance of mitochondrial dynamics is disrupted. This leads to mitochondrial fragmentation, decreased mitochondrial membrane potential, higher levels of mROS and oxidative injury. The AMPK activator AICAR inhibits the increased phosphorylation of Drp1 and the translocation of Drp1 to mitochondria by salvaging mitochondrial function in an AMPK/Drp1 dependent manner, which has a similar effect to Drp1 inhibitor Mdivi-1. These data show that AMPK, as an upstream negative regulator of Drp1, ameliorates mitochondrial dysfunction induced by S. uberis infection.

Explore the influencing factors and construct random forest models of post-stroke depression at 3 months in males and females.

BACKGROUND: Post-stroke depression (PSD) is one of the most common neuropsychiatric complications after stroke. The occurrence, development and prognosis of PSD have long been different between males and females. The main purpose of this study was to explore the influencing factors of PSD at 3 months in males and females, and construct random forest (RF) models to rank the influencing factors. METHODS: This is a prospective multicenter cohort study (Registration number: ChiCTR-ROC-17013993). Stroke patients hospitalized in the department of Neurology of three hospitals in Wuhan were enrolled from May 2018 to August 2019. Scale assessments were performed 24 hours after admission and 3 months after stroke onset. Binary logistic regression analysis was used for univariate and multivariate (stepwise backward method) analysis, when p was less than 0.05, the difference between groups was considered statistically significant. Lastly, the RF models were constructed according to the results of multivariate regression analysis. RESULTS: This study found that several baseline variables were associated with PSD at 3 months in males and females. RF model ranked them as stroke severity (OR [odds ratio] =1.17, p < 0.001, 95%CI [confidence interval]:1.11-1.24), neuroticism dimension (OR = 1.06, p = 0.002, 95%CI:1.02-1.10), physical exercise (OR = 0.62, p = 0.007, 95%CI:0.44-0.88), sleeping time < 5 h (OR = 1.91, p = 0.006, 95% CI:1.20-3.04) and atrial fibrillation (OR = 4.18, p = 0.012, 95%CI:1.38-12.68) in males. In females, RF model ranked them as psychological resilience (OR = 0.98, p = 0.015, 95%CI:0.96-1.00), ability of daily living (OR = 0.98, p = 0.001, 95%CI:0.97-0.99), neuroticism dimension (OR = 1.11, p = 0.002, 95%CI:1.04-1.18) and subjective support (OR = 1.11, p < 0.001, 95%CI:1.05-1.78). CONCLUSION: The study found influencing factors of PSD at 3 months were different in males and females, and construct RF models to rank them according to their importance. This suggests that clinicians should focus their interventions on sex-specific influencing factors in order to improve the prognosis of PSD patients. TRIAL REGISTRATION: ChiCTR-ROC-17013993.

Molecular Epidemiology and Antimicrobial Resistance of Outbreaks of Klebsiella pneumoniae Clinical Mastitis in Chinese Dairy Farms.

Klebsiella pneumoniae is an opportunistic pathogen that causes serious infections in humans and animals. However, the availability of epidemiological information on clinical mastitis due to K. pneumoniae is limited. To acquire new information regarding K. pneumoniae mastitis, data were mined about K. pneumoniae strains on dairy cattle farms (farms A to H) in 7 Chinese provinces in 2021. Hypermucoviscous strains of K. pneumoniae were obtained by the string test. MICs of antimicrobial agents were determined via the broth microdilution method. Ten antimicrobial resistance genes and virulence genes were identified by PCR. The prevalence of K. pneumoniae was 35.91% (65/181), and 100% of the bacteria were sensitive to enrofloxacin. Nine antimicrobial resistance genes and virulence genes were identified and compared among farms. The hypermucoviscous phenotype was present in 94.44% of isolates from farm B, which may be a function of the rmpA virulence gene. Based on these data, the multidrug-resistant strains SD-14 and HB-21 were chosen and sequenced. Genotypes were assayed for K. pneumoniae isolates from different countries and different hosts using multilocus sequence typing (MLST). Ninety-four sequence types (STs) were found, and 6 STs present a risk for spreading in specific regions. Interestingly, ST43 was observed in bovine isolates for the first time. Our study partially reveals the current distribution characteristics of bovine K. pneumoniae in China and may provide a theoretical basis for the prevention and treatment of bovine K. pneumoniae mastitis. IMPORTANCE K. pneumonia is ubiquitous in nature and infects a wide range of hosts, including animals, and humans. It is one of the leading inducements of clinical mastitis (CM) in dairy cows, a prevalent and costly disease that is predominantly associated with bacterial infection. In general, CM caused by Gram-negative bacteria is more difficult to cure than that associated with Gram-positive pathogens, with an average cost per case of 211.03 U.S. dollars (USD) for Gram-negative bacterial infections compared with 133.73 USD for Gram-positive bacterial CM cases. After Escherichia coli, K. pneumoniae is the second most common Gram-negative cause of bovine CM, but it is the most detrimental in terms of decreased milk yield, discarded milk, treatment costs, death, and culling. In view of the economic implications of K. pneumoniae infection in dairy farming, research into population structure and antibiotic resistance is particularly important.