Using part of the initial analgesic dose as the epidural test dose did not delay the onset of labor analgesia: a randomized controlled clinical trial.

BACKGROUND: Epidural test dose for labor analgesia is controversial and varies widely in clinical practice. It is currently unclear whether using a portion of the initial dose for analgesia as the test dose delays the onset time of analgesia, compared to the traditional test dose. METHODS: One hundred and twenty-six parturients who chose epidural analgesia during labor were randomly assigned to two groups. The first dose in group L was 3 ml 1.5% lidocaine, and in the RF group was 10 ml 0.1% ropivacaine combined with 2 µg/ml fentanyl. After 3 min of observation, both groups received 8 ml 0.1% ropivacaine combined with 2 µg/ml fentanyl. The onset time of analgesia, motor and sensory blockade level, numerical pain rating scale, patient satisfaction score, and side effects were recorded. RESULTS: The onset time of analgesia in group RF was similar to that in group L (group RF vs group L, 7.0 [5.0-9.0] minutes vs 8.0 [5.0-11.0] minutes, p = 0.197). The incidence of foot numbness (group RF vs group L, 34.9% vs 57.1%, p = 0.020) and foot warming (group RF vs group L, 15.9% vs 47.6%, p < 0.001) in group RF was significantly lower than that in group L. There was no difference between the two groups on other outcomes. CONCLUSIONS: Compared with 1.5% lidocaine 3 ml, 0.1% ropivacaine 10 ml combined with 2 µg/ml fentanyl as an epidural test dose did not delay the onset of labor analgesia, and the side effects were slightly reduced. CLINICAL TRIAL REGISTRATION: http://www.chictr.org.cn (ChiCTR2100043071).

Functionalized hydrogels in neural injury repairing.

Repairing injuries to the nervous system has always been a prominent topic in clinical research. Direct suturing and nerve displacement surgery are the primary treatment options, but they may not be suitable for long nerve injuries and may require sacrificing the functionality of other autologous nerves. With the emergence of tissue engineering, hydrogel materials have been identified as a promising technology with clinical translation potential for repairing nervous system injuries due to their excellent biocompatibility and ability to release or deliver functional ions. By controlling their composition and structure, hydrogels can be Functionalized and almost fully matched with nerve tissue and even simulate nerve conduction function and mechanical properties. Thus, they are suitable for repairing injuries to both the central and peripheral nervous systems. This article provides a review of recent research progress in functionalized hydrogels for nerve injury repair, highlighting the design differences among various materials and future research directions. We strongly believe that the development of functionalized hydrogels has great potential for improving the clinical treatment of nerve injuries.

[Progression in the application of machine learning in acute respiratory distress syndrome].

Acute respiratory distress syndrome (ARDS) is a clinical syndrome defined by acute onset of hypoxemia and bilateral pulmonary opacities not fully explained by cardiac failure or volume overload. At present, there is no specific drug treatment for ARDS, and the mortality rate is high. The reason may be that ARDS has rapid onset, rapid progression, complex etiology, and great heterogeneity of clinical manifestations and treatment. Compared with traditional data analysis, machine learning algorithms can automatically analyze and obtain rules from complex data and interpret them to assist clinical decision making. This review aims to provide a brief overview of the machine learning progression in ARDS clinical phenotype, onset prediction, prognosis stratification, and interpretable machine learning in recent years, in order to provide reference for clinical.

Mesenchymal Stem Cell-Secreted TGF-ß1 Restores Treg/Th17 Skewing Induced by Lipopolysaccharide and Hypoxia Challenge via miR-155 Suppression.

Background: Regulatory T cell (Treg)/T helper (Th) 17 skewing is important in the development of acute respiratory distress syndrome (ARDS). Immunomodulatory effects of mesenchymal stem cell- (MSC-) secreted transforming growth factor- (TGF-) ß1 on CD4+ T cells are environment-sensitive and lack discussion in hypoxic and inflammatory conditions. Methods: Mouse splenic CD4+ T cells were precoated with anti-CD3 (5 µg/ml) and anti-CD28 (2 µg/ml) overnight. RAW264.7 cells were added as antigen-presenting cells (APCs). T cells with and without RAW264.7 cells were treated with various LPS concentrations of 0, 10, 100, and 1000 ng/ml or/and at hypoxia condition of 5% O2. Based on LPS (100 ng/ml) and hypoxia conditions (5% O2) as stimuli, MSCs were set as direct coculture or indirect coculture by transwell system. Anti-TGF-ß1 neutralization antibody was added to explore the role of TGF-ß1 among the soluble factors secreted by MSCs; miR-155 overexpression of CD4+ T cells was performed by transfection, and then, cells were added to the MSC-CD4+ T cell coculture system in hypoxic- and LPS-stimulated condition. After 48 hours, cells or supernatants were collected for detection of frequency of Treg and Th17 subsets, CD4+ T cell apoptosis and proliferation capacity assay by flow cytometry, secretion of INF-γ, IL-17A, IL-21, TGF-ß1, and IL-10 by ELISA, and levels of miR-155, Rorc, Foxp3, and Ptpn2 mRNA expression of CD4+ T cells by RT-PCR. Results: MSCs could restore skewed Treg/Th17 induced by LPS and hypoxia compared to groups without MSCs with increased secretion of TGF-ß1, IL-10, and IL-17A (P < 0.05) and attenuate the increased expression of miR-155 in CD4+ T cells via cell-to-cell contact mechanism while TGF-ß1 neutralization significantly inhibited the effects of MSCs restoring skewed Treg/Th17 and abolished its effect on miR-155 expression in CD4+ T cells. Conclusions: These findings suggested miR-155 suppression of CD4+ T cells mediated MSC-secreted TGF-ß1 modulating skewed Treg/Th17 induced by LPS-hypoxia challenge, providing evidence when proposing future T lymphocyte-targeted cell therapy in a specific condition.

Association of serum cardiac troponin I and severity of coronary stenosis in patients with varied renal functions: a retrospective cohort study.

BACKGROUND AND OBJECTIVE: Recent studies showed cardiac troponin I (cTnI) might be a non-invasive biomarker to estimate the severity of coronary stenosis. However, serum cTnI is also found associated with renal function. The study objective is to analyse the association of serum cTnI and severity of coronary stenosis in patients with varied renal functions. DESIGN: A retrospective cohort study. SETTING: The First Affiliated Hospital, College of Medicine, Zhejiang University in Hangzhou, China. POPULATION: A total of 6487 subjects who underwent elective coronary angiography between January 2017 to June 2020 were involved in this study. PRIMARY OUTCOMES: Severity of coronary stenosis was divided into three degrees based on Gensini score, mild coronary stenosis, moderate coronary stenosis and severe coronary stenosis. RESULTS: By using ordinal logistic regression, serum cTnI was associated with severity of coronary stenosis (OR=1.14, p<0.05). By construction and comparison of two models for predicting severity of coronary stenosis, the addition of cTnI significantly improved the predictive ability of the model. Differences between areas under the curves were 0.03, 0.03, 0.03, 0.12 (all p<0.05). Net reclassification improvements were 0.08, 0.05, 0.05, 0.35, respectively, in varied renal functions. Compared with the participants with normal renal function and without hypertroponinaemia, groups of participants with hypertroponinaemia showed higher ORs. ORs were 3.52, 4.20, 4.45, 6.00, respectively, as renal function decreased (all p<0.05). CONCLUSIONS: In this cohort of patients with stable coronary artery disease and varied renal functions, cTnI was intensely associated with severity of coronary stenosis which based on Gensini score. The presentation of hypertroponinaemia in patients with impaired renal function always indicates a higher risk of severe coronary stenosis.

d-Amino Acid-Based Metabolic Labeling Enables a Fast Antibiotic Susceptibility Test of Both Isolated Bacteria and Bronchoalveolar Lavage Fluid.

The threat of multidrug-resistant bacteria has escalated rapidly, increasing the demand for accurate antibiotic susceptibility tests (ASTs). Traditional bacterial growth yield-based ASTs often take overnight to report, delaying the timely guidance of antibiotic use. Here, a fluorescent d-amino acid (FDAA) labeling-based AST (FaAST) is reported, which can quickly provide accurate minimum inhibitory concentrations (MICs). The FDAA-labeling signals that reflect the bacterial metabolic status underlie the flow cytometry-based strategy for MIC determination. Resistant bacteria show a reluctant decline in FDAA-labeling (inhibited metabolism) after treatment with the corresponding antibiotics, whereas susceptible bacteria demonstrate quick responses to low doses of drugs. The MICs are determined based on the changing trends in labeling. After testing 23 clinical isolates and laboratory strains of the most critical drug-resistant bacteria against a panel of representative antibiotics, FaAST shows a high susceptibility category with an accuracy of 98.13%. Moreover, FaAST can also make quick and accurate diagnosis against bronchoalveolar lavage fluids collected from hospital-acquired pneumonia patients, saving 2-4 days in guiding antibiotic use for this life-threatening infection. Thus, the speed, accuracy, and broad applicability of FaAST will be valuable in informing antibiotic decisions when treating critical infections caused by drug-resistant bacteria.

Overexpressing TGF-ß1 in mesenchymal stem cells attenuates organ dysfunction during CLP-induced septic mice by reducing macrophage-driven inflammation.

BACKGROUND: Sepsis remains a leading cause of death in critically ill patients. It is well known that mesenchymal stem cells (MSCs) are a promising therapy partly due to their paracrine-mediated immunoregulatory function. Previous study demonstrated that transforming growth factor-beta1 (TGF-ß1) is an important cytokine secreted by MSCs and that it participates in MSC-mediated macrophage phenotype switch from pro-inflammatory to pro-resolution. In addition, the transformation of macrophage phenotype may be a potential treatment for sepsis. However, the therapeutic effect of overexpressing TGF-ß1 in MSCs (MSC-TGF-ß1) on sepsis is not well understood. Therefore, this study aimed to evaluate the effects of TGF-ß1 overexpressing MSCs on organ injury in cecal ligation and puncture (CLP)-induced septic mice and to detect the changes in macrophage phenotype during this process. METHODS: Mouse MSCs stably transfected with TGF-ß1 were constructed and injected into CLP-induced septic mice via tail vein. After 24 h, the mice were sacrificed; then, the histopathology of the organ was evaluated by hematoxylin-eosin (H&E) staining. Inflammatory cytokines were detected by ELISA. Macrophage infiltration and phenotype transformation in the tissues were determined by immunohistochemistry and flow cytometry. In addition, we performed adoptive transfer of mouse peritoneal macrophage pretreated with TGF-ß1 overexpressing MSCs in septic mice. RESULTS: We found that infusion of TGF-ß1 overexpressing MSCs attenuated the histopathological impairment of the organ, decreased the pro-inflammatory cytokine levels and inhibited macrophage infiltration in tissues. TGF-ß1 overexpressing MSCs induced macrophage phenotypes changed from pro-inflammatory to pro-resolution in inflammatory environment. The adoptive transfer of mouse peritoneal macrophages pretreated with TGF-ß1 overexpressing MSCs also relieved organ damage in CLP-induced septic mice. CONCLUSION: Under septic conditions, TGF-ß1 overexpressing MSCs can enhance the therapeutic effects of MSCs on organ injury and inflammation as a result of reduced macrophage infiltration and induced macrophages transformation, the adoptive transfer of macrophages treated with TGF-ß1 overexpressing MSCs also relieved organ damage. This will provide new hope for the treatment of sepsis.

Overexpression of TGFß1 in murine mesenchymal stem cells improves lung inflammation by impacting the Th17/Treg balance in LPS-induced ARDS mice.

BACKGROUND: T helper 17 cells (Th17)/regulatory T cells (Treg), as subtypes of CD4+ T cells, play an important role in the inflammatory response of acute respiratory distress syndrome (ARDS). However, there is still a lack of effective methods to regulate the differentiation balance of Th17/Treg. It was proven that mesenchymal stem cells (MSCs) could regulate the differentiation of CD4+ T cells, but the mechanism is still unclear. TGFß1, a paracrine cytokine of MSCs, could also regulate the differentiation of Th17/Treg but is lowly expressed in MSCs. Therefore, mouse MSCs (mMSCs) overexpressing TGFß1 were constructed by lentivirus transduction and intratracheally transplanted into LPS-induced ARDS mice in our study. The aim of this study was to evaluate the therapeutic effects of mMSCs overexpressing TGFß1 on inflammation and immunoregulation by impacting the Th17/Treg balance in LPS-induced ARDS mice. METHODS: mMSCs overexpressing TGFß1 were constructed using lentiviral vectors. Then, mouse bone-marrow-derived MSCs (mBM-MSC) and mBM-MSC-TGFß1 (mBM-MSC overexpressing TGFß1) were transplanted intratracheally into ARDS mice induced by lipopolysaccharide. At 3 and 7 days after transplantation, the mice were sacrificed, and the homing of the mMSCs was assayed by ex vivo optical imaging. The relative numbers of Th17 and Treg in the lungs and spleens of mice were detected by FCM. IL-17A and IL-10 levels in the lungs of mice were analysed by western blot. Permeability and inflammatory cytokines were evaluated by analysing the protein concentration of BALF using ELISA. Histopathology of the lungs was assessed by haematoxylin and eosin staining and lung injury scoring. Alveolar lung fibrosis was assessed by Masson's trichrome staining and Ashcroft scoring. The mortality of ARDS mice was followed until 7 days after transplantation. RESULTS: The transduction efficiencies mediated by the lentiviral vectors ranged from 82.3 to 88.6%. Overexpressing TGFß1 inhibited the proliferation of mMSCs during days 5-7 (p < 0.05) but had no effect on mMSC differentiation or migration (p > 0.05). Compared to that in the LPS + mBM-MSC-NC group mice, engraftment of mMSCs overexpressing TGFß1 led to much more differentiation of T cells into Th17 or Treg (p < 0.05), improved permeability of injured lungs (p < 0.05) and ameliorative histopathology of lung tissue in ARDS mice (p < 0.05). Moreover, IL-17A content was also decreased while IL-10 content was increased in the LPS + mBM-MSC-TGFß1 group compared with those in the LPS + mBM-MSC-NC group (p < 0.05). Finally, mMSCs overexpressing TGFß1 did not aggravate lung fibrosis in ARDS mice (p > 0.05). CONCLUSION: MSCs overexpressing TGFß1 could regulate lung inflammation and attenuate lung injuries by modulating the imbalance of Th17/Treg in the lungs of ARDS mice.

MSC-secreted TGF-ß regulates lipopolysaccharide-stimulated macrophage M2-like polarization via the Akt/FoxO1 pathway.

BACKGROUND: An uncontrolled inflammatory response is a critical pathophysiological feature of sepsis. Mesenchymal stem cells (MSCs) induce macrophage phenotype polarization and reduce inflammation in sepsis. MSC-secreted transforming growth factor beta (TGF-ß) participated in the immune modulatory function of MSCs. However, the underlying mechanism of MSC-secreted TGF-ß was not fully elucidated in regulation macrophage M2-like polarization. METHODS: The paracrine effects of MSCs on macrophage polarization were studied using a co-culture protocol with LPS-stimulated RAW264.7 cells/mouse peritoneal macrophages and MSCs. The effect of TGF-ß in the co-culture system was blocked by the TGF-ß receptor inhibitor. To determine the role of MSC-secreted TGF-ß, we used recombinant TGF-ß to culture with LPS-stimulated RAW264.7 cells. In addition, we employed antibody microarray analysis to determine the mechanisms of MSC secreted TGF-ß on LPS-stimulated RAW264.7 cell/mouse peritoneal macrophage M2-like polarization. Furthermore, we used an Akt inhibitor and a FoxO1 inhibitor to inhibit the Akt/FoxO1 pathway. The nuclear translocation of FoxO1 was detected by Western blot. RESULTS: MSCs induced LPS-stimulated RAW264.7 cell/mouse peritoneal macrophage polarization towards the M2-like phenotype and significantly reduced pro-inflammatory cytokine levels via paracrine, which was inhibited by TGF-ß receptor inhibitor. Furthermore, we found that MSC-secreted TGF-ß enhanced the macrophage phagocytic ability. The antibody microarray analysis and Western blot verified that TGF-ß treatment activated the Akt/FoxO1 pathway in LPS-stimulated macrophages, TGF-ß-induced FoxO1 nuclear translocation and obviously expressed in the cytoplasm, the effects of TGF-ß regulatory effects on LPS-stimulated macrophage were inhibited by pre-treatment with Akt inhibitor and FoxO1 inhibitor. CONCLUSIONS: TGF-ß secreted by MSCs could skew LPS-stimulated macrophage polarization towards the M2-like phenotype, reduce inflammatory reactions, and improve the phagocytic ability via the Akt/FoxO1 pathway, providing potential therapeutic strategies for sepsis.

Overexpressing p130/E2F4 in mesenchymal stem cells facilitates the repair of injured alveolar epithelial cells in LPS-induced ARDS mice.

BACKGROUND: Low differentiation rates of mesenchymal stem cells (MSCs) limit their therapeutic effects on patients in clinical studies. Our previous study demonstrated that overexpressing p130 or E2F4 affected the multipotential differentiation of MSCs, and the underlying mechanism was attributed to the regulation of the G1 phase. Improving the efficiency of MSC differentiation into epithelial cells is considered to be a new method. Therefore, this study was conducted to evaluate the effects of overexpressing p130 or E2F4 in MSCs on improving re-epithelization in lipopolysaccharide (LPS)-induced ARDS animals. METHODS: Mouse MSCs (mMSCs) stably transfected with p130 and E2F4 were transplanted intratracheally into LPS-induced ARDS mice. After 7 and 14 days, the mice were sacrificed, and the histopathology of the lungs was assessed by haematoxylin-eosin staining and lung injury scoring. Homing and differentiation of mMSCs were analysed by labelling and tracking mMSCs with NIR815 dye and immunofluorescent staining. Surfactant proteins A and C and occludin in the lungs were assessed by western blot. Permeability was evaluated by analysing the protein concentration of BALF using ELISA. Alveolar fluid clearance was assessed by absorbance measurements of BALF. Lung fibrosis was assessed by Masson's trichrome staining and Ashcroft scoring. RESULTS: The engraftment of mMSCs overexpressing p130 or E2F4 led to attenuated histopathological impairment of the lung tissue, and the lung injury scores of the LPS+mBM-MSC-p130 and LPS+mBM-MSC-E2F4 groups were also decreased (p < 0.05). Overexpression of p130 or E2F4 also increased the retention of mMSCs in the lung (p < 0.05), increased differentiation into type II alveolar epithelial cells (p < 0.05), and improved alveolar epithelial permeability (p < 0.05). Additionally, mMSCs overexpressing p130 or E2F4 inhibited lung fibrosis according to the deposition of collagen and the fibrosis score in the lungs (p < 0.05). CONCLUSION: Overexpressing p130 or E2F4 in mMSCs could further improve the injured structure and function of epithelial cells in the lungs of ARDS mice as a result of improved differentiation of mMSCs into epithelial cells.

Stable overexpression of p130/E2F4 affects the multipotential abilities of bone-marrow-derived mesenchymal stem cells.

Bone-marrow-derived mesenchymal stem cells (MSCs) have great potential in transplantation medicine due to their multiple advantages. However, the controlled differentiation of MSCs is one of the key aspects of effective clinical transplantation. Growing evidence suggests that the cell cycle plays an important role in regulating differentiation, while p130 and E2F4 are key to cell cycle checkpoints. The aim of the study is to evaluate the effects and mechanism of p130/E2F4 on the multidifferentiation of MSCs. Our data showed that the transduction efficiencies of p130 or E2F4 mediated by lentiviral vectors were 80.3%-84.4%. p130 and E2F4 mRNA expression was significantly higher in MSC-p130 and MSC-E2F4 cells than in MSC normal control (NC) cells. Similar results were also observed for p130 and E2F4 protein expression. After osteogenic or adipogenic differentiation, the G1 phase was significantly delayed in the MSC-p130 and MSC-E2F4 groups compared with that in the MSC-NC group. However, the G1 phase in the MSC-p130 and MSC-E2F4 groups did the opposite after chondrogenic differentiation. Moreover, overexpressing p130 or E2F4 significantly improved osteogenic differentiation while inhibiting adipogenic and chondrogenic differentiation of mouse MSCs (mMSCs). Moreover, overexpressing p130 or E2F4 significantly improved migration but not proliferation of mMSCs. Our data suggest that cell cycle regulation may be involved in p130/E2F4-mediated changes in the multipotential abilities of bone-marrow-derived mMSCs.

Midazolam increases preload dependency during endotoxic shock in rabbits by affecting venous vascular tone.

BACKGROUND: Septic patients often require sedation in intensive care unit, and midazolam is one of the most frequently used sedatives among them. But the interaction between midazolam and septic shock is not known. The aim of this study is to investigate the effects of midazolam on preload dependency in an endotoxic shock model by evaluating systemic vascular tone and cardiac function. METHODS: Eighteen rabbits were randomly divided into three groups: Control group, MID1 group and MID2 group. Rabbits underwent ketamine anaesthesia and mechanical ventilation, and haemodynamic assessments were recorded in three groups (T0). Endotoxic shock was induced by lipopolysaccharide intravenously, and fluid resuscitation and norepinephrine were administered to obtain the baseline mean arterial pressure (MAP) (T1). Rabbits received equivalent normal saline (Control) and two consecutive dosages of midazolam: 0.3 mg kg-1 h-1 (MID1) and 3 mg kg-1 h-1 (MID2) (T2). Rabbits received another round of fluid challenge and norepinephrine infusion to return the MAP to normal (T3). RESULTS: No significant differences in haemodynamic parameters were observed in three groups at T0, T1 or T3. Midazolam infusion significantly increased pulse pressure variation (PPV) and stroke volume variation (SVV) compared to the values in Control group, and MAP, central venous pressure (CVP), mean systemic filling pressure (Pmsf) and cardiac output (CO) decreased at T2. Same effects were observed with increasing doses of midazolam, and resistance for venous return (Rvr) decreased (MID1 vs. MID2) at T2. PPV and SVV increased significantly at T2 compared to the values at T1. MAP, CVP, Pmsf and CO decreased in MID1 and MID2 groups. Rvr also decreased in MID2 group (T2 vs. T1). Midazolam did not affect cardiac function index, systemic vascular resistance or artery resistance (T2 vs. T1). CONCLUSIONS: Midazolam administration promoted preload dependency in septic shock models via decreased venous vascular tone without affecting cardiac function.

Chemokine receptor 7 overexpression promotes mesenchymal stem cell migration and proliferation via secreting Chemokine ligand 12.

Great interest has been shown in mesenchymal stem cell (MSC) therapy in a wide variety of clinical domains. However, the therapeutic efficiency depends on the proliferation and migration of MSCs. Chemokine receptors are involved in regulating the proliferation and migration to the specific organs of MSCs in different microenvironments. CXC receptor seven (CXCR7), a newly discovered Chemokine ligand 12 (CXCL12) receptor, has organ specificity for tumour migration. We hypothesized that CXCR7 expression affects proliferation and migration of MSCs. In present study, we constructed long-term and stable mMSCs lines overexpressing and suppressing CXCR7 modifications with lentiviral vectors. The transduction efficiencies, mRNA and protein expression of CXCR7 were significantly regulated. CXCR7 gene overexpression promoted mMSCs proliferation and migration, whereas suppressing CXCR7 had the opposite effect. Additional CXCL12 improved the vertical migration of mMSCs. The overexpression of CXCR7 increased the MSC-secreted CXCL12, VCAM-1, CD44 and MMP2 levels, which contributed to the improvement of mMSC proliferation and migration. Therefore, overexpressing CXCR7 improved the proliferation and migration of mMSCs, which may be attributable to the CXCL12 secreted by MSCs, leading to a positive feedback loop for CXCL12/CXCR7 axis. Our results may provide a potential method for improving the treatment effectiveness of mMSCs by overexpressing CXCR7.