The dual effects of dexmedetomidine on intestinal barrier and intestinal motility during sepsis.

BACKGROUND: Sepsis, characterized by dysregulated host responses to infection, remains a critical global health concern, with high morbidity and mortality rates. The gastrointestinal tract assumes a pivotal role in sepsis due to its dual functionality as a protective barrier against injurious agents and as a regulator of motility. Dexmedetomidine, an α2-adrenergic agonist commonly employed in critical care settings, exhibits promise in influencing the maintenance of intestinal barrier integrity during sepsis. However, its impact on intestinal motility, a crucial component of intestinal function, remains incompletely understood. METHODS: In this study, we investigated dexmedetomidine's multifaceted effects on intestinal barrier function and motility during sepsis using both in vitro and in vivo models. Sepsis was induced in Sprague-Dawley rats via cecal ligation and puncture. Rats were treated with dexmedetomidine post-cecal ligation and puncture, and various parameters were assessed to elucidate dexmedetomidine's impact. RESULTS: Our findings revealed a dichotomous influence of dexmedetomidine on intestinal physiology. In septic rats, dexmedetomidine administration resulted in improved intestinal barrier integrity, as evidenced by reduced mucosal hyper-permeability and morphological alterations. However, a contrasting effect was observed on intestinal motility, as dexmedetomidine treatment inhibited both the frequency and amplitude of contractions in isolated intestinal strips and decreased the distance of ink migration in vivo. Additionally, dexmedetomidine suppressed the secretion of pro-motility hormones while having no influence on hormones that inhibit intestinal peristalsis. CONCLUSION: The study revealed that during sepsis, dexmedetomidine exhibited protective effects on barrier integrity, although concurrently it hindered intestinal motility, partly attributed to its modulation of pro-motility hormone secretion. These findings underscore the necessity of a comprehensive understanding of dexmedetomidine's impact on multiple facets of gastrointestinal physiology in sepsis management, offering potential implications for therapeutic strategies and patient care.

Protective Effect of Electroacupuncture on the Barrier Function of Intestinal Injury in Endotoxemia through HO-1/PINK1 Pathway-Mediated Mitochondrial Dynamics Regulation.

Background and Aims: Endotoxemia (ET) is a common critical illness in patients receiving intensive care and is associated with high mortality and prolonged hospital stay. The intestinal epithelial cell dysfunction is regarded as the "engine" of deteriorated ET. Although electroacupuncture (EA) can mitigate endotoxin-induced intestinal epithelial cell dysfunction in ET, the mechanism through which EA improves endotoxin-induced intestinal injury for preventing ET deterioration needs further investigation. Methods: An in vivo ET model was developed by injecting lipopolysaccharide (LPS) in wild-type and PINK1-knockout mice. An in vitro model was also established by incubating epithelial cells in the serum samples obtained from both groups of mice. Hemin and zinc protoporphyrin IX (ZnPP) were applied to activate or inhibit heme oxygenase 1 (HO-1) production. EA treatment was performed for 30 min consecutively for 5 days before LPS injection, and on the day of the experiment, EA was performed throughout the process. Samples were harvested at 6 h after LPS induction for analyzing tissue injury, oxidative stress, ATP production, activity of diamine oxidase (DAO), and changes in the levels of HO-1, PTEN-induced putative kinase 1 (PINK1), mitochondrial fusion and fission marker gene, caspase-1, and interleukin 1 beta (IL-1ß). Results: In the wild-type models (both in vivo and vitro), EA alleviated LPS-induced intestinal injury and mitochondrial dysfunction, as indicated by decreased reactive oxygen species (ROS) production and oxygen consumption rate (OCR) and reduced levels of mitochondrial fission proteins. EA treatment also boosted histopathological morphology, ATP levels, DAO activity, and levels of mitochondrial fusion proteins in vivo and vitro. The effect of EA was enhanced by hemin but suppressed by Znpp. However, EA + AP, Znpp, or hemin had no effects on the LPS-induced, PINK1-knocked out mouse models. Conclusion: EA may improve the HO-1/PINK1 pathway-mediated mitochondrial dynamic balance to protect the intestinal barrier in patients with ET.

The Polo-Like Kinase 1-Mammalian Target of Rapamycin Axis Regulates Autophagy to Prevent Intestinal Barrier Dysfunction During Sepsis.

The intestines play a crucial role in the development of sepsis. The balance between autophagy and apoptosis in intestinal epithelial cells is dynamic and determines intestinal permeability. The present study focused on the potential role of autophagy in sepsis-induced intestinal barrier dysfunction and explored the mechanisms in vivo and in vitro. Excessive apoptosis in intestinal epithelia and a disrupted intestinal barrier were observed in septic mice. Promoting autophagy with rapamycin reduced intestinal epithelial apoptosis and restored intestinal barrier function, presenting as decreased serum diamine oxidase (DAO) and fluorescein isothiocyanate-dextran 40 (FD40) levels and increased expression of zonula occludens-1 (ZO-1) and Occludin. Polo-like kinase 1 (PLK1) knockdown in mice ameliorated intestinal epithelial apoptosis and the intestinal barrier during sepsis, whereas these effects were reduced with chloroquine and enhanced with rapamycin. PLK1 also promoted cell autophagy and improved lipopolysaccharide-induced apoptosis and high permeability in vitro. Moreover, PLK1 physically interacted with mammalian target of rapamycin (mTOR) and participated in reciprocal regulatory crosstalk in intestinal epithelial cells during sepsis. This study provides novel insight into the role of autophagy in sepsis-induced intestinal barrier dysfunction and indicates that the PLK1-mTOR axis may be a promising therapeutic target for sepsis.

PLK1 protects intestinal barrier function in sepsis: A translational research.

BACKGROUND: Sepsis and its related complications are very challenging in the intensive care unit, among which intestinal barrier injury is a general manifestation. Polo-like kinase 1 (PLK1) is widely studied in cancer, while its role in sepsis is poorly understood. In this study, the efficiency of PLK1 as a marker of intestinal barrier function as well as a predictor of mortality in sepsis was evaluated. METHODS: The level of serum PLK1 was measured in septic patients (n = 51) and controls (n = 20); subsequently, its correlation with serum diamine oxidase (DAO), d-lactate, and endotoxin levels and its ability topredict mortality were analysed. The survival rate and barrier injury degree were also assessed in septic mice. RESULTS: Serum PLK1 levels were elevated in septic patients, were negatively correlated with serum DAO, d-lactate, and endotoxin levels, and had a high predictive value for 28-day mortality in patients. The serum PLK1 level in non-survivors was lower. The expression of PLK1 in the intestine was decreased in septic mice, and overexpression or inhibition of PLK1 alleviated or aggravated intestinal barrier injury, respectively, as evaluated by Chiu's score, serum levels of DAO and d-lactate, and expression of tight junction proteins. Overexpressing PLK1 also decreased the 72-hour death rate of septic mice. Further study also revealed the negative correlation of PLK1 and IL-6 in patients, and increasing or interfering with PLK1 expression reduced or increased the serum IL-6 level in mice. CONCLUSIONS: PLK1 plays a critical role in intestinal barrier function during sepsis, providing a novel perspective for sepsis therapy in the clinic.

[Clinical observation of electroacupuncture combined with Qingyi Xianxiong Decoction in the treatment of acute respiratory distress syndrome due to severe acute pancreatitis].

OBJECTIVE: To observe the clinical effect of electroacupuncture combined with Qingyi Xianxiong Decoction on the treatment of acute respiratory distress syndrome (ARDS) caused by severe acute pancreatitis (SAP). METHODS: From February 2021 to April 2022, 120 patients with ARDS caused by SAP who were admitted to the department of critical care medicine of Tianjin Nankai Hospital and whose syndrome differentiation belonged to the syndrome of knot chest were selected. They were randomly divided into pure traditional Chinese medicine group and acupuncture medicine group, with 60 cases in each group. The pure traditional Chinese medicine group was received Qingyi Xianxiong Decoction on the basis of conventional western medicine treatment, and the acupuncture medicine group was received electric acupuncture treatment on the basis of the pure traditional Chinese medicine group. The two groups continued to be treated for 7 days. The primary outcome was the ventilator-free days within 28 days after admission to the intensive care unit (ICU), and the secondary outcome measures were mechanical ventilation time, the length of ICU stay, total lenth of hospital stay, time of intra-abdominal pressure recovery, scores of organ function, oxygenation index (PaO2/FiO2), serum inflammatory factors, blood amylase, urine amylase, etc. RESULTS: Compared with the pure traditional Chinese medicine group, the ventilator-free days in the acupuncture medicine group within 28 days after admission to the ICU were significantly longer [day: 22.10±2.29 vs. 20.97±2.31, P < 0.05, odds ratio (OR) = 1.24, 95% confidence interval (95%CI) was 1.053-1.460, P < 0.05]. The time of mechanical ventilation, the length of ICU stay, total length of hospital stay, and recovery time of intra-abdominal pressure were significantly shortened [mechanical ventilation time (days): 5.90±2.29 vs. 7.03±2.31, the length of ICU stay (days): 8.07±1.89 vs. 12.08±2.23, total length of hospital stay (days): 19.55±6.82 vs. 22.28±5.19, recovery time of intra-abdominal pressure (days): 6.05±1.81 vs. 8.45±1.76, all P < 0.05]. The Murray score and bedside index for severity in acute pancreatitis (BISAP) score of the two groups after 7 days of treatment were significantly lower than those before treatment, while PaO2/FiO2 was significantly higher than those before treatment, and the Murray score of the acupuncture medicine group after 7 days of treatment was significantly lower than that of the pure traditional Chinese medicine group [score: 0.50 (0.33, 0.75) vs. 1.00 (1.00, 1.33), P < 0.05], PaO2/FiO2 was significantly higher than that in the pure traditional Chinese medicine group [mmHg (1 mmHg ≈ 0.133 kPa): 390.75±27.73 vs. 330.02±42.34, P < 0.05]. With the prolongation of treatment time, the levels of inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), serum amylase and urine amylase in both groups after treatment continued to decrease, and the levels of the inflammatory factors in the acupuncture medicine group after 7 days of treatment were significantly lower than those in the pure traditional Chinese medicine group [TNF-α (ng/L): 38.20±10.00 vs. 45.35±5.09, IL-6 (ng/L): 0.95±0.44 vs. 7.42±1.39, CRP (mg/L): 8.55±2.79 vs. 36.20±13.97, all P < 0.05]. Subgroup analysis showed that biliary system disease was a risk factor for the duration of mechanical ventilation ≥ 7 days in the treatment of ARDS with acupuncture and medicine (OR = 2.728, 95%CI was 1.293-5.754). CONCLUSIONS: Compared with the pure traditional Chinese medicine, acupuncture combined can better reduce the clinical symptoms of patients with ARDS caused by SAP, promote the recovery of patients, and reduce systemic inflammatory reaction, which is worthy of clinical promotion.

PLK1 protects intestinal barrier function during sepsis by targeting mitochondrial dynamics through TANK-NF-κB signalling.

BACKGROUND: Intestinal barrier integrity in the pathogenesis of sepsis is critical. Despite an abundance of evidence, the molecular mechanism of the intestinal barrier in sepsis pathology remains unclear. Here, we report a protective role of polo-like kinase 1 (PLK1) in intestinal barrier integrity during sepsis. METHODS: Mice with PLK1 overexpression (CAG-PLK1 mice) or PLK1 inhibition (BI2536-treated mice) underwent caecal ligation and puncture (CLP) to establish a sepsis model. The intestinal barrier function, apoptosis in the intestinal epithelium, mitochondrial function and NF-κB signalling activity were evaluated. To suppress the activation of NF-κB signalling, the NF-κB inhibitor PDTC, was administered. The Caco-2 cell line was chosen to establish an intestinal epithelial injury model in vitro. RESULTS: Sepsis destroyed intestinal barrier function, induced excessive apoptosis in the intestinal epithelium, and disrupted the balance of mitochondrial dynamics in wild-type mice. PLK1 overexpression alleviated sepsis-induced damage to the intestinal epithelium by inhibiting the activation of NF-κB signalling. PLK1 colocalized and interacted with TANK in Caco-2 cells. Transfecting Caco-2 cells with TANK-SiRNA suppressed NF-κB signalling and ameliorated mitochondrial dysfunction, apoptosis and the high permeability of cells induced by lipopolysaccharide (LPS). Furthermore, TANK overexpression impaired the protective effect of PLK1 on LPS-induced injuries in Caco-2 cells. CONCLUSION: Our findings reveal that the PLK1/TANK/NF-κB axis plays a crucial role in sepsis-induced intestinal barrier dysfunction by regulating mitochondrial dynamics and apoptosis in the intestinal epithelium and might be a potential therapeutic target in the clinic.

Nicotinamide mononucleotide ameliorates acute lung injury by inducing mitonuclear protein imbalance and activating the UPRmt.

Mitochondria need to interact with the nucleus under homeostasis and stress to maintain cellular demands and nuclear transcriptional programs. Disrupted mitonuclear interaction is involved in many disease processes. However, the role of mitonuclear signaling regulators in endotoxin-induced acute lung injury (ALI) remains unknown. Nicotinamide adenine dinucleotide (NAD+) is closely related to mitonuclear interaction with its central role in mitochondrial metabolism. In the current study, C57BL/6J mice were administrated with lipopolysaccharide 15 mg/kg to induce endotoxin-induced ALI and investigated whether the NAD+ precursor nicotinamide mononucleotide (NMN) could preserve mitonuclear interaction and alleviate ALI. After pretreatment with NMN for 7 days, NAD+ levels in the mitochondrial, nucleus, and total intracellular were significantly increased in endotoxemia mice. Moreover, supplementation of NMN alleviated lung pathologic injury, reduced ROS levels, increased MnSOD activities, mitigated mitochondrial dysfunction, ameliorated the defects in the nucleus morphology, and these cytoprotective effects were accompanied by preserving mitonuclear interaction (including mitonuclear protein imbalance and the mitochondrial unfolded protein response, UPRmt). Furthermore, NAD+-mediated mitonuclear protein imbalance and UPRmt are probably regulated by deacetylase Sirtuin1 (SIRT1). Taken together, our results indicated that NMN pretreatment ameliorated ALI by inducing mitonuclear protein imbalance and activating the UPRmt in an SIRT1-dependent manner.

Effect of Dexmedetomidine on Intestinal Barrier in Patients Undergoing Gastrointestinal Surgery-A Single-Center Randomized Clinical Trial.

INTRODUCTION: Gastrointestinal failure results in death in critically ill patients. This study aimed to explore the effect of dexmedetomidine (DEX) on intestinal barrier function and its mechanism in critically ill patients undergoing gastrointestinal surgery. METHODS: Patients undergoing gastrointestinal surgery were randomized into the DEX group (n = 21) or midazolam (MID) group (n = 21). Sufentanil was used for analgesia in both groups. In the DEX group, DEX was loaded (1 µg/kg) before sedation and infused (0.7 µg/kg/h) during sedation. In the MID group, MID was loaded (0.05 mg/kg) before sedation and infused (0.1 mg/kg/h) during sedation. The mean arterial pressure , heart rate , borborygmus resumption time , first defecation time, length of intensive care unit stay, and length of hospital stay were observed. The diamine oxidase (DAO), D-lactate , TNF-α, IL-6, and α7nAChR levels in plasma or hemocytes were detected before the start of sedation (0 h) and after sedation (24 h). RESULTS: No significant differences in age, sex, body mass index, Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores were noted (P > 0.05). The mean arterial pressure between 0 h and 24 h showed no significant difference between the groups (P > 0.05), but the heart rate was significantly lower in the DEX group (P = 0.042). The borborygmus resumption time was significantly earlier in the DEX group (P = 0.034). The lengths of intensive care unit stay (P = 0.016) and hospital stay (P = 0.031) were significantly shorter in the DEX group. The TNF-α level in the DEX group was lower at 24 h than 0 h. The D-lactate level was significantly lower in the DEX group than the MID group at 24 h (P = 0.016). The expression of α7nAChR in the DEX group was significantly higher at 24 h than 0 h (P < 0.05). CONCLUSIONS: DEX maintained intestinal barrier integrity in patients undergoing gastrointestinal surgery through the cholinergic anti-inflammatory pathway.

Minocycline Pretreatment Prevents Blood-Brain Barrier Disruption in Septic Rats.

INTRODUCTION: The aim of the study was to explore the mechanism by which minocycline protects the blood-brain barrier (BBB) in septic rats. METHODS: A sepsis rat model was generated in healthy, male Sprague-Dawley rats by cecal ligation and puncture (CLP). The rats were randomly divided into four groups and treated as follows: sham-operated plus normal saline (Sham + S group), CLP plus normal saline (CLP + S group), CLP plus minocycline pretreatment (CLP + M1 group), and CLP plus minocycline treatment (CLP + M2 group). Rats in the CLP + M1 group received 45 mg/kg minocycline by intraperitoneal injection every 12 h for 72 h. Rats in the Sham + S and CLP + S groups were injected with the same volume of normal saline every 12 h for 72 h. Rats in the CLP + M2 group were intraperitoneally injected with 45 mg/kg minocycline immediately after CLP and once every 12 h for 72 h. All rats were sacrificed at 72 h after operation. Tumor necrosis factor α and interleukin 6 levels, the expression of ionized calcium-binding adaptor molecule-1 (Iba-1), and the permeability of the BBB were measured. The expression of matrix metalloproteinases-9 (MMP-9) and the tight junction proteins zonula occludens-1 (ZO-1) and occludin was detected by Western blot. In addition, Evans blue (EB) staining, immunohistochemistry, and ELISA analysis were carried out. RESULTS: Minocycline pretreatment significantly inhibited microglial activation, decreased the sepsis-induced expression of MMP-9, increased the expression of ZO-1 and occludin, and improved the permeability of the BBB. Minocycline treatment failed to inhibit microglial activation, decrease the sepsis-induced expression of MMP-9, increase the expression of ZO-1 or occluding, or improve the permeability of the BBB. CONCLUSIONS: Minocycline pretreatment can effectively improve the altered permeability of the BBB caused by sepsis. The mechanism may be related to the inhibition of microglial activation and MMP-9 expression and increased expression of ZO-1 and occludin.

Sepsis induces muscle atrophy by inhibiting proliferation and promoting apoptosis via PLK1-AKT signalling.

Sepsis and sepsis-induced skeletal muscle atrophy are common in patients in intensive care units with high mortality, while the mechanisms are controversial and complicated. In the present study, the atrophy of skeletal muscle was evaluated in sepsis mouse model as well as the apoptosis of muscle fibres. Sepsis induced atrophy of skeletal muscle and apoptosis of myofibres in vivo and in vitro. In cell-based in vitro experiments, lipopolysaccharide (LPS) stimulation also inhibited the proliferation of myoblasts. At the molecular level, the expression of polo-like kinase 1 (PLK1) and phosphorylated protein kinase B (p-AKT) was decreased. Overexpression of PLK1 partly rescued LPS-induced apoptosis, proliferation suppression and atrophy in C2C12 cells. Furthermore, inhibiting the AKT pathway deteriorated LPS-induced atrophy in PLK1-overexpressing C2C12 myotubes. PLK1 was found to participate in regulating apoptosis and E3 ubiquitin ligase activity in C2C12 cells. Taken together, these results indicate that sepsis induces skeletal muscle atrophy by promoting apoptosis of muscle fibres and inhibiting proliferation of myoblasts via regulation of the PLK1-AKT pathway. These findings enhance understanding of the mechanism of sepsis-induced skeletal muscle atrophy.

Sepsis induces variation of intestinal barrier function in different phase through nuclear factor kappa B signaling.

The intestinal barrier function disrupted in sepsis, while little is known about the variation in different phases of sepsis. In this study, mouse models of sepsis were established by caecal ligation and puncture (CLP). The H&E staining of sections and serum diamine oxidase concentration were evaluated at different timepoint after CLP. TUNEL assay and EdU staining were performed to evaluate the apoptosis and proliferation of intestinal epithelium. Relative protein expression was assessed by Western blotting and serum concentrations of pro-inflammatory cytokines was measured by ELISA. The disruption of intestinal barrier worsened in the first 24 h after the onset of sepsis and gradually recovered over the next 24 h. The percentage of apoptotic cell increased in the first 24 h and dropped at 48 h, accompanied with the proliferative rate of intestinal epithelium inhibited in the first 6 h and regained in the later period. Furthermore, the activity of nuclear factor kappa B (NF-κB) presented similar trend with the intestinal barrier function, shared positive correction with apoptosis of intestinal epithelium. These findings reveal the conversion process of intestinal barrier function in sepsis and this process is closely correlated with the activity of NF-κB signaling.

LncRNA DANCR improves the dysfunction of the intestinal barrier and alleviates epithelial injury by targeting the miR-1306-5p/PLK1 axis in sepsis.

Intestinal barrier dysfunction often occurs in various acute or chronic pathological conditions and has been identified as an important clinical problem. Herein, we explored the biological role and molecular mechanism of Polo-like kinase 1 (PLK1) and differentiation antagonizing non-protein coding RNA (DANCR) in intestinal barrier dysfunction caused by sepsis. RT-qPCR analysis was used to examine PLK1, miR-1306-5p, and DANCR expression in NCM460 cells after LPS treatment. TUNEL assay and Western blot analysis were performed to explore PLK1 function in cell apoptosis and intestinal barrier in vitro. Hematoxylin and eosin staining, Western blot analysis, and TUNEL assay were used to investigate DANCR function in the intestinal barrier and cell apoptosis in vivo. The interaction between miR-1306-5p and PLK1 (or DANCR) was validated by luciferase reporter assay. As a result, PLK1 overexpression decreased cell apoptosis and promoted intestinal barrier function. Moreover, DANCR was validated as a sponge of miR-1306-5p to target PLK1. In addition, we found that DANCR overexpression decreased intestinal mucosal permeability and colon mucosa epithelial cell apoptosis in vivo. Conclusively, DANCR improved intestinal barrier dysfunction and alleviated epithelial injury by targeting the miR-1306-5p/PLK1 axis in sepsis.

Development and validation of a predictive score for ICU delirium in critically ill patients.

BACKGROUND: The incidence of delirium in intensive care unit (ICU) patients is high and associated with a poor prognosis. We validated the risk factors of delirium to identify relevant early and predictive clinical indicators and developed an optimized model. METHODS: In the derivation cohort, 223 patients were assigned to two groups (with or without delirium) based on the CAM-ICU results. Multivariate logistic regression analysis was conducted to identify independent risk predictors, and the accuracy of the predictors was then validated in a prospective cohort of 81 patients. RESULTS: A total of 304 patients were included: 223 in the derivation group and 81 in the validation group, 64(21.1%)developed delirium. The model consisted of six predictors assessed at ICU admission: history of hypertension (RR = 4.367; P = 0.020), hypoxaemia (RR = 3.382; P = 0.018), use of benzodiazepines (RR = 5.503; P = 0.013), deep sedation (RR = 3.339; P = 0.048), sepsis (RR = 3.480; P = 0.018) and mechanical ventilation (RR = 3.547; P = 0.037). The mathematical model predicted ICU delirium with an accuracy of 0.862 (P < 0.001) in the derivation cohort and 0.739 (P < 0.001) in the validation cohort. No significant difference was found between the predicted and observed cases of ICU delirium in the validation cohort (P > 0.05). CONCLUSIONS: Patients' risk of delirium can be predicted at admission using the early prediction score, allowing the implementation of early preventive interventions aimed to reduce the incidence and severity of ICU delirium.

Inhibition of miR-155 alleviates sepsis-induced inflammation and intestinal barrier dysfunction by inactivating NF-κB signaling.

MicroRNA-155 (miR-155) is implicated in the pathological processes of sepsis. However, the function and regulatory mechanism of miR-155 in sepsis-induced inflammation and intestinal barrier dysfunction remain unknown. In this study, mouse models of sepsis were established by caecal ligation and puncture (CLP). To reduce miR-155 expression, the mice were injected for three consecutive days with an miR-155 inhibitor (80 mg/kg) before CLP. The serum DAO concentration was measured by ELISA, and histological changes in the intestine were identified by H&E staining 24 h after CLP. FITC-dextran assays were used to evaluate intestinal permeability. MiR-155 gene expression was evaluated with RT-PCR, and relative protein expression was assessed by Western blotting. NCM460 cells were transfected with an miR-155 mimic/miR-155 inhibitor or pretreated with an NF-κB inhibitor before LPS treatment, and the cytokines levels, miR-155 gene expression and relative protein expression were measured. Sepsis increased miR-155, DAO and FITC-dextran levels and reduced Occludin and ZO-1 expression. Mice injected with the miR-155 inhibitor recovered from the damages. Transfection of NCM460 cells with the miR-155 mimic elevated the NF-κB (P65) and p-NF-κB (p-P65) localization and expression in the nucleus, which was reversed by the miR-155 inhibitor. Pretreatment with an NF-κB inhibitor suppressed inflammation, improved cell permeability to FITC-dextran and increased Occludin and ZO-1 levels. Transfection with the miR-155 inhibitor decreased TNF-α and IL-6 levels, reduced cell permeability to FITC-dextran and increased ZO-1 and Occludin expression. The effects induced by transfection with the miR-155 mimic, including elevated TNF-α and IL-6 levels, hyperpermeability to FITC-dextran and reduced ZO-1 and Occludin expression, were partly rescued by pretreatment with the NF-κB inhibitor. These findings reveal that the miR-155 inhibitor alleviates inflammation and intestinal barrier dysfunction by inactivating NF-κB signaling during sepsis.

[Role and mechanism of splenic myeloid-derived suppressor cells in sepsis-induced adrenal injury in mice].

OBJECTIVE: To investigate the role and mechanism of splenic myeloid-derived suppressor cells (MDSCs) in sepsis-induced adrenal injury (SAI). METHODS: Thirty male C57 mice aged 6-8 weeks were randomly divided into normal control group (n = 5), sham operation group (Sham group, n = 5), sepsis model group [cecal ligation and perforation (CLP) group, n = 10] and sepsis+splenectomy group (CLPS group, n = 10). The sepsis model of mice was reproduced by CLP method. In Sham group, only the cecum was opened and separated, then closed, without CLP. In CLPS group, the spleen was removed before CLP. In normal control group, no challenge was given. After 24 hours, the rats were sacrificed by anesthesia, and peripheral blood, spleen, bone marrow, and bilateral adrenal glands were harvested. The pathological of adrenal gland was assessed by hematoxylin-eosin (HE) staining under optical microscope. The ratio of MDSCs in peripheral blood, spleen and bone marrow was determined by flow cytometry. The expressions of MDSCs surface antigen CD11b, Gr-1 and interleukins (IL-6, IL-1ß) mRNA in adrenal tissue were measured by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Western Blot was used to detect the expressions of mammalian rapamycin target protein (mTOR) pathway related proteins including total mTOR (T-mTOR), phosphorylation of mTOR (p-mTOR) and caspase-3. RESULTS: The adrenal cortex and medulla of the normal control group and Sham group were intact and the structure was clear under optical microscope, while in the CLP group, the adrenal gland showed edema, cortical hemorrhage and cell edema. Compared with the CLP group, the adrenal tissue injury was significantly reduced in the CLPS group. Compared with the normal control group and Sham group, MDSCs ratio in the peripheral blood was significantly increased and significantly reduced in the spleen in the CLP group, but there was no significant difference in bone marrow, the expression levels of CD11b, Gr-1, IL-6, IL-1ß mRNA and caspase-3 protein were increased significantly and p-mTOR protein expression was significantly decreased in adrenal tissue, there was no significant difference in the expression of T-mTOR protein. Compared with the CLP group, in the CLPS group, the MDSCs ratio in the peripheral blood was significantly decreased (0.143±0.011 vs. 0.324±0.023, P < 0.01), the expression levels of CD11b, Gr-1, IL-6 , IL-1ß mRNA and caspase-3 protein in adrenal gland were significantly decreased [CD11b mRNA (2-ΔΔCt): 2.90±0.56 vs. 5.74±0.13, Gr-1 mRNA (2-ΔΔCt): 2.71±0.14 vs. 4.59±0.46, IL-6 mRNA (2-ΔΔCt): 2.44±0.64 vs. 5.17±1.04, IL-1ß mRNA (2-ΔΔCt): 3.58±0.52 vs. 4.44±0.26, caspase-3 protein (caspase-3/GAPDH): 0.05±0.01 vs. 0.13±0.02, all P < 0.01], the p-mTOR protein expression was significantly increased (p-mTOR/GAPDH: 0.61±0.11 vs. 0.27±0.04, P < 0.01). CONCLUSIONS: The spleen is the major source of MDSCs in SAI. Splenectomy can attenuate SAI by reducing mobilization of MDSCs and activating the mTOR signaling pathway.

Malignant glomus tumor of the thyroid gland: a case report.

OBJECTIVE: Primary malignant glomus tumors of the thyroid gland are a rare occurrence. METHODS: A 68-year-old man found a mass on the right side of his neck in October 2017. An X-ray examination on 9 January 2018 showed multiple round reinforced masses in both sides of the lung. Computed tomography imaging of the neck showed a low-density mass on the right side of the thyroid gland. RESULTS: The immunohistochemistry results were positive for smooth muscle actin, calponin, collagen IV, and Ki-67 60%. The patient received chemotherapy starting on 17 January 2018, 8 February 2018, and 11 March 2018. The chemotherapy drugs included ifosfamide, epirubicin, and cisplatin. However, the patient subsequently developed multiple organ failure and died in April 2018, approximately 6 months after the initial discovery of the mass in his neck. CONCLUSIONS: Primary malignant glomus tumors of the thyroid gland are rare, and examination of their pathology and immunohistochemistry is vital for making an accurate final diagnosis. This case also indicates that primary malignant glomus tumors of the thyroid gland may have a poor prognosis, despite chemotherapy.

Percutaneous dilatational tracheostomy versus fibre optic bronchoscopy-guided percutaneous dilatational tracheostomy in critically ill patients: a randomised controlled trial.

BACKGROUND: To determine whether fibre optic bronchoscopy-guided percutaneous dilatational tracheostomy (FOB-PDT) is a better option in critically ill patients, we compared the efficacy and incidence of procedure complications between PDT with and without FOB. METHODS: We included 90 patients with oral intubation and mechanical ventilation who received PDT with (n = 45, FOB-PDT group) and without (n = 45, PDT group) FOB. For all patients, a simplification of the Griggs technique was used in this study with a central venous catheter set and dilating forceps. Demographic data, body mass index (BMI), Sequential Organ Failure Assessment (SOFA) score, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, rate of first-time success, complication rate and time of procedure were evaluated in both groups. PDT was performed guided by FOB only in the FOB-PDT group. RESULTS: The rate of major complications, including minor or major haemorrhage requiring intervention and subcutaneous emphysema in the neck or pneumothorax, was significantly higher in the PDT group than in the PDT-FOB group (40% vs. 20%, P < 0.05). Significant differences were observed between the two groups with respect to the rate of first-time success (64.4% vs. 93.3%, P < 0.05); the rate of first-time success puncture with the puncture needle in the PDT-FOB group was higher than that in the PDT group (93.3% vs. 75.6%, P < 0.05). The mean procedure duration was significantly longer in the PDT group than in the PDT-FOB group (12.9 ± 1.1 vs. 9.8 ± 1.2 min, P < 0 .05). CONCLUSIONS: PDT with FOB offers the advantages of a high rate of first-time success, a low complication rate and short-procedure duration. Thus, FOB-PDT is a better option in critically ill patients.

Asymptomatic Mediastinal Extra-adrenal Paraganglioma as a Cause of Sudden Death: A Case Report.

A 23-year-old female patient was referred for treatment of a posterior mediastinal tumour. There was no history of hypertension or headache and no other complaints. The patient's blood pressure increased to 210/125 mmHg after surgically manipulating the tumour, subsequently reversing to severe hypotension (25/15 mmHg) immediately after the tumour was removed. The life-threatening and irreversible blood pressure drop was difficult to treat with fluid and vasopressors, and the patient ultimately died of cardio-respiratory failure. Asymptomatic paraganglioma can be non-functional but can also be fatal. For any lump in the thoracic cavity, paraganglioma should be ruled out.