Bacterial DNA metabolism analysis by metagenomic next-generation sequencing (mNGS) after treatment of bloodstream infection.

BACKGROUND: With the advent of metagenomic next-generation sequencing (mNGS), the time of DNA metabolism can be explored after bacteria be killed. In this study, we applied mNGS in investigation of the clearance profile of circulating bacteria DNA. METHODS: All of the rabbits were injected with the inactivated Escherichia coli. Using mNGS, we analyzed serial samples of plasma collected from rabbits to detect clearance profile of circulating E. coli DNA. RESULTS: In this study, we found that the of E. coli DNA could still be detected 6 h after injecting killed bacteria. The clearance half-lives associated with the 2 phases are 0.37 and 1.81 h. We also explored there is no correlation between the disease severity with the E. coli DNA reads in circulation. CONCLUSIONS: After the bacteria were completely killed, their DNA could still be detected in the blood circulation. The metabolism of bacterial DNA in the circulation had two phases: fast and slow phases, and there were no correlations between the level of bacteria reads with the severity of patients' disease after the bacteria have been completely killed.

Association between the LRP5 rs556442 gene polymorphism and the risks of NAFLD and CHD in a Chinese Han population.

BACKGROUND: Multiple studies have demonstrated the involvement of low-density lipoprotein receptor-related protein 5 (LRP5) in metabolism-related diseases. This study explored the relationship between the LRP5 rs556442 gene polymorphism and the risks of non-alcoholic fatty liver disease (NAFLD) and coronary heart disease (CHD) in a Chinese Han population. METHODS: This retrospective case-control study included 247 patients with NAFLD, 200 patients with CHD, 118 patients with both NAFLD and CHD, and 339 healthy controls from June 2018 to June 2019 at Qingdao Municipal Hospital. Basic information and clinical characteristics were collected for all subjects. The genotype and allele frequency of LRP5 rs556442 were determined. RESULTS: The genotype distributions of LRP5 rs556442 differed significantly between the CHD and NAFLD + CHD groups (P < 0.05). The LRP5 rs556442 GG genotype markedly promoted the risk of NAFLD in CHD patients [odds ratio (OR) = 2.857, 95% confidence interval (CI): 1.196-6.824, P = 0.018). After adjustment for sex, age, and body mass index (BMI), this association remained significant (OR = 3.252, 95% CI: 1.306-8.102, P = 0.011). In addition, the LRP5 rs556442 AA + AG genotype was associated with an increased BMI in obese NAFLD patients (OR = 1.526, 95% CI: 1.004-2.319, P = 0.048). However, after adjustment for sex and age, this association was no longer significant (OR = 1.504, 95% CI: 0.991-2.282, P = 0.055). CONCLUSIONS: This study found that the LRP5 rs556442 GG genotype increased the risk of NAFLD in CHD patients and AA + AG genotype may be associated with an increased BMI in obese NAFLD patients among a Chinese Han population. Trial registration ChiCTR, ChiCTR1800015426. Registered 28 March 2018-Retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=26239 .

Bradykinin/bradykinin 1 receptor promotes brain microvascular endothelial cell permeability and proinflammatory cytokine release by downregulating Wnt3a.

Stroke is a life-threatening disease with limited therapeutic options. Damage to the blood-brain barrier (BBB) is the key pathological feature of ischemic stroke. This study explored the role of the bradykinin (BK)/bradykinin 1 receptor (B1R) and its mechanism of action in the BBB. Human brain microvascular endothelial cells (BMECs) were used to test for cellular responses to BK by using the Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine staining, enzyme-linked immunosorbent assay, flow cytometry, immunofluorescence, cellular permeability assays, and western blotting to evaluate cell viability, cytokine production, and reactive oxygen species (ROS) levels in vitro. A BBB induced by middle cerebral artery occlusion was used to evaluate BBB injuries, and the role played by BK/B1R in ischemic/reperfusion (I/R) was explored in a rat model. Results showed that BK reduced the viability of BMECs and increased the levels of proinflammatory cytokines (interleukin 6 [IL-6], IL-18, and monocyte chemoattractant protein-1) and ROS. Additionally, cellular permeability was increased by BK treatment, and the expression of tight junction proteins (claudin-5 and occludin) was decreased. Interestingly, Wnt3a expression was inhibited by BK and exogenous Wnt3a restored the effects of BK on BMECs. In an in vivo I/R rat model, knockdown of B1R significantly decreased infarct volume and inflammation in I/R rats. Our results suggest that BK might be a key inducer of BBB injury and B1R knockdown might provide a beneficial effect by upregulating Wnt3a.

Hypercapnia Exacerbates the Blood-Brain Barrier Disruption Via Promoting HIF-1a Nuclear Translocation in the Astrocytes of the Hippocampus: Implication in Further Cognitive Impairment in Hypoxemic Adult Rats.

Hypercapnia in combination with hypoxemia is usually present in severe respiratory disease in the intensive care unit (ICU) and can lead to more severe cognitive dysfunction. Increasing evidence has indicated that the compromised blood-brain barrier (BBB) in the hippocampus in hypoxemia conditions can result in cognitive dysfunction. However, the role and underlying mechanism of hypercapnia in the BBB disruption remains poorly known. A rat model of hypercapnia was first established in this study by intubation and mechanical ventilation with a small-animal ventilator. After this, the cognitive function of the experimental rats was assessed by the Morris water maze test. The BBB permeability was evaluated by the Evans Blue (EB) test and brain water content (BWC). Western blot analysis was carried out to detect the protein expressions of total and nuclear hypoxia-inducible factor-1α (HIF-1α), matrixmetalloproteinase-9 (MMP-9) and Aquaporins-4 (AQP-4) in the hippocampus tissue. Double immunofluorescence further verified the protein expression of different biomarkers was localized in the astrocytes of the hippocampus. Hypercapnia alone did not disrupt the BBB, but it could further enhance the BBB permeability in hypoxemia. Concomitantly, up-regulation of nuclear HIF-1α, AQP-4, MMP-9 protein expression along with increased degradation of the occludin and claudin-5 proteins was found in the hypercapnia rat model, while the total HIF-1α remained unchanged. Interestingly, these changes were independent of the acidosis induced by hypercapnia. Of note, after premedication of 2-Methoxyestradiol (2ME2, an inhibitor of HIF-1α nuclear translocation), the disrupted BBB could be restored resulting in improvement of the cognitive impairment. Meanwhile, accumulation of nuclear HIF-1α, protein expression of AQP-4 and MMP-9 and protein degradation of the occludin and claudin-5 were decreased. Thus, our study demonstrated that hypercapnia can further disrupt the BBB through promoting HIF-1α nuclear translocation and up-regulation of AQP-4 and MMP-9 in hypoxemia. It is therefore suggested that the cascade of hypercapnia-induced nuclear HIF-1α protein translocation in hypoxia-activated astrocytes may be a potential target for ameliorating cognitive impairment.

Hypercapnia induces IL-1ß overproduction via activation of NLRP3 inflammasome: implication in cognitive impairment in hypoxemic adult rats.

BACKGROUND: Cognitive impairment is one of common complications of acute respiratory distress syndrome (ARDS). Increasing evidence suggests that interleukin-1 beta (IL-1ß) plays a role in inducing neuronal apoptosis in cognitive dysfunction. The lung protective ventilatory strategies, which serve to reduce pulmonary morbidity for ARDS patients, almost always lead to hypercapnia. Some studies have reported that hypercapnia contributes to the risk of cognitive impairment and IL-1ß secretion outside the central nervous system (CNS). However, the underlying mechanism of hypercapnia aggravating cognitive impairment under hypoxia has remained uncertain. This study was aimed to explore whether hypercapnia would partake in increasing IL-1ß secretion via activating the NLRP3 (NLR family, pyrin domain-containing 3) inflammasome in the hypoxic CNS and in aggravating cognitive impairment. METHODS: The Sprague-Dawley (SD) rats that underwent hypercapnia/hypoxemia were used for assessment of NLRP3, caspase-1, IL-1ß, Bcl-2, Bax, and caspase-3 expression by Western blotting or double immunofluorescence, and the model was also used for Morris water maze test. In addition, Z-YVAD-FMK, a caspase-1 inhibitor, was used to treat BV-2 microglia to determine whether activation of NLRP3 inflammasome was required for the enhancing effect of hypercapnia on expressing IL-1ß by Western blotting or double immunofluorescence. The interaction effects were analyzed by factorial ANOVA. Simple effects analyses were performed when an interaction was observed. RESULTS: There were interaction effects on cognitive impairment, apoptosis of hippocampal neurons, activation of NLRP3 inflammasome, and upregulation of IL-1ß between hypercapnia treatment and hypoxia treatment. Hypercapnia + hypoxia treatment caused more serious damage to the learning and memory of rats than those subjected to hypoxia treatment alone. Expression levels of Bcl-2 were reduced, while that of Bax and caspase-3 were increased by hypercapnia in hypoxic hippocampus. Hypercapnia markedly increased the expression of NLRP3, caspase-1, and IL-1ß in hypoxia-activated microglia both in vivo and in vitro. Pharmacological inhibition of NLRP3 inflammasome activation and release of IL-1ß might ameliorate apoptosis of neurons. CONCLUSIONS: The present results suggest that hypercapnia-induced IL-1ß overproduction via activating the NLRP3 inflammasome by hypoxia-activated microglia may augment neuroinflammation, increase neuronal cell death, and contribute to the pathogenesis of cognitive impairments.

Pyruvate dehydrogenase complex deficiency masked by septic shock-induced lactic acidosis: a case report.

Pyruvate dehydrogenase complex (PDHC) deficiency is a common genetic disorder leading to lactic acidosis, which can also result from several nongenetic conditions, such as septic shock. The present study reports a case of PDHC deficiency masked by septic shock-induced lactic acidosis. This case involved a 16-year-old adolescent with poor exercise tolerance compared with his peers, and no underlying diseases. The disease onset was characterized by cough, fever, and dyspnea, with hypotension and elevated lactate levels, which indicated septic shock. However, severe hypoglycemia and lactic acidosis persisted despite resolution of a pulmonary infection and correction of septic shock, requiring continuous intravenous infusion of 50% glucose. Although the patient did not experience acute kidney injury and had normal urine output, continuous renal replacement therapy was used to regulate the internal environment owing to the severity of the acidosis. The diagnosis of PDHC deficiency was considered on the basis of the persistent hypoglycemia and hyperlactatemia, before genetic mutation testing was completed. The clinical thinking process required a rich accumulation of pathophysiological knowledge. This article reports a case of PDHC deficiency masked by septic shock-induced lactic acidosis to raise awareness of the disease and avoid misdiagnosis and missed diagnosis.

Hyperglycemia induces microglial pyroptosis by increasing oxygen extraction rate: Implication in neurological impairment during ischemic stroke.

Elevated levels of blood glucose in patients with ischemic stroke are associated with a worse prognosis. The present study aimed to explore whether hyperglycemia promotes microglial pyroptosis by increasing the oxygen extraction rate in an acute ischemic stroke model. C57BL/6 mice that underwent middle cerebral artery occlusion were used for assessment of blood glucose level and neurological function. The cerebral oxygen extraction ratio (CERO2), oxygen consumption rate (OCR) and partial pressure of brain tissue oxygen (PbtO2) were measured. To investigate the significance of the NOD­like receptor protein 3 (NLRP3) inflammasome, NLRP3­/­ mice were used, and the expression levels of NLRP3, caspase­1, full­length gasdermin D (GSDMD­FL), GSDMD­N domain (GSDMD­N), IL­1ß and IL­18 were evaluated. In addition, Z­YVAD­FMK, a caspase­1 inhibitor, was used to treat microglia to determine whether activation of the NLRP3 inflammasome was required for the enhancing effect of hyperglycemia on pyroptosis. It was revealed that hyperglycemia accelerated cerebral injury in the acute ischemic stroke model, as evidenced by decreased latency to fall and the percentage of foot fault. Hyperglycemia aggravated hypoxia by increasing the oxygen extraction rate, as evidenced by increased CERO2 and OCR, and decreased PbtO2 in response to high glucose treatment. Furthermore, hyperglycemia­induced microglial pyroptosis was confirmed by detection of increased levels of caspase­1, GSDMD­N, IL­1ß and IL­18 and a decreased level of GSDMD­FL. However, the knockout of NLRP3 attenuated these effects. Pharmacological inhibition of caspase­1 also reduced the expression levels of GSDMD­N, IL­1ß and IL­18 in microglial cells. These results suggested that hyperglycemia stimulated NLRP3 inflammasome activation by increasing the oxygen extraction rate, thus leading to the aggravation of pyroptosis following ischemic stroke.

Clusterin attenuates blood-brain barrier damage and cognitive impairment by inhibiting astrocyte aging in mice with sepsis-associated encephalopathy.

Sepsis-associated encephalopathy (SAE) is a severe complication of sepsis, however, its exact mechanism remains unknown. This study aimed to evaluate whether clusterin is essential to the development of SAE during the aging process of astrocytes. In the study, septic mice were established with cecal ligation and puncture (CLP) and lipopolysaccharides were applied to astrocytes in vitro. Evan's blue dye was used in vivo to show blood-brain barrier (BBB) permeability. A morris water maze test was conducted to assess cognitive functions of the mice. Clusterin-knockout mice were used to examine the effect of clusterin on sepsis. The astrocytes were transfected with lentivirus expressing clusterin cDNA for clusterin overexpression or pYr-LV-clusterin small hairpin RNA for clusterin knockdown in vitro. The expression of clusterin, p-p53, p21, GDNF, and iNOS was detected. he CLP mice exhibited a higher clusterin expression in hippocampus tissue, aging astrocytes, lower GDNF expression and higher iNOS expression, accompanied with BBB damage and cognitive deficiency. Following clusterin knockout, this pathological process was further enhanced. In vitro, following lipopolysaccharides treatment, astrocytes exhibited increased clusterin, p-p53, p21, iNOS and decreased GDNF. Following clusterin knockdown, the cells exhibited a further increase in p-p53, p21, and iNOS and decrease in GDNF. Clusterin overexpression, however, helped inhibit astrocytes aging and neuroinflammation evidenced by decreased p-p53, p21, iNOS and increased GDNF. The present study has revealed that clusterin may exert its neuroprotective effect by preventing aging in astrocytes, suppressing the secretion of iNOS and promoting GNDF release.

Heat stress induces IL-1ß and IL-18 overproduction via ROS-activated NLRP3 inflammasome: implication in neuroinflammation in mice with heat stroke.

Heat stroke induced cerebral damage via neuroinflammation. This study aimed to approach whether heat stress would promote NOD-like receptor protein 3 (NLRP3) inflammasome via reactive oxygen species (ROS). The mice were randomly divided into the sham group, the heat stress group, and the heat stress + TEMPOL (ROS scavenger) group. And the NLRP3 -/- mice were applied and divided into the NLRP3 -/-  + sham group and the NLRP3 -/-  + heat stress group. Furthermore, the BV2 cells were divided into four groups following the intervention measures: the heat stress + TEMPOL group, the heat stress + Z-VAD-FMK (caspase-1 inhibitor) group, the heat stress group, and the control group. ROS levels were examined. The expression levels of NLRP3, caspase-1, IL-1ß, and IL-18 were detected by western blotting and double immunofluorescence. We found that heat stress attack induced excessive ROS in microglia and subsequently activated NLRP3 inflammasome in both mice and BV2 cells. When ROS scavenged, the expression level of NLRP3 was downregulated. Furthermore, with NLRP3 inflammasome activation, the expression levels of caspase-1, IL-1ß, and IL-18 were increased. In NLRP3 -/- mice, however, the caspase-1, IL-1ß, and IL-18 were significantly declined. Further experiments showed that pretreatment of caspase-1 inhibitor decreased the expression levels of IL-1ß and IL-18. These results suggest that heat stress attack caused neuroinflammation via excessive ROS activating the NLRP3 inflammasome in microglia cells.

[Predictive value of sepsis-induced coagulopathy score on 30-day mortality in septic patients].

OBJECTIVE: To evaluate the predictive effect of sepsis-induced coagulopathy (SIC) score level on the prognosis of septic patients under sepsis 3.0 criteria. METHODS: A retrospective single-center observational study was conducted on the septic patients admitted to the department of critical care medicine and the department of emergency in Guangdong Provincial People's Hospital from August 2016 to July 2021. The baseline data, laboratory indexes and SIC scores of the patients were collected on the first and fourth (4th) day after hospitalization. Whether the patients were survival within 30 days after enrollment was recorded. Univariate and multivariate Logistic regression were used to analyze the independent risk factors for 30-day mortality in septic patients. The receiver operator characteristic curve (ROC curve) was drawn to evaluate the predictive value of SIC score on the 30-day prognosis of septic patients. RESULTS: A total of 173 patients met the inclusion criteria including 111 (64%) survivors and 62 (36%) non-survivors. There were significant differences in lymphocyte count (LYM), sequential organ failure assessment (SOFA), oxygenation index (PaO2/FiO2) and cardiovascular SOFA score between the survival group and the non-survival group. And there were no significant differences in other indexes. On the first day of admission, there were statistically significant differences in PaO2/FiO2, cardiovascular SOFA score, LYM, SIC score between the non-survival group and the survival group. There were significant differences in international normalized ratio (INR), prothrombin activity (PTA), prothrombin time (PT), PaO2/FiO2, cardiovascular SOFA score, LYM, C-reactive protein (CRP) and procalcitonin (PCT) between the two groups on the 4th day after admission. The mortality of septic patients increased with the increase of SIC score. Binary Logistic regression analysis showed that SIC score and LYM on the 4th day after admission were independent risk factors for 30-day mortality in septic patients (both P < 0.05). The ROC curve showed that SIC score had a certain predictive value for the 30-day prognosis of septic patients [area under the ROC curve (AUC) = 0.712, 95% confidence interval (95%CI) was 0.629-0.794, P < 0.001]. The predictive value of SIC score combined with LYM was better than that of the two alone (AUC = 0.748, 95%CI was 0.688-0.828, P < 0.001). CONCLUSIONS: The SIC score has a certain predictive value for the 30-day prognosis of septic patients. The predictive value of SIC score combined with LYM is better than that of the two alone, which is expected to be a potential indicator for early assessment of the condition and prognosis of septic patients.

Human albumin aggravates cerebral edema by disrupting the blood­brain barrier in a rat model of ischemic stroke.

Cerebral edema and elevated intracranial pressure (ICP) are common complications observed following ischemic stroke. Osmotherapy has been used as a foundation to manage ICP induced by cerebral edema, and albumin is one of the most commonly used osmotic agents. The present study aimed to explore whether albumin lowered ICP by reducing cerebral edema when albumin elevated the colloid osmotic pressure (COP) of plasma. Sprague­Dawley rats that underwent middle cerebral artery occlusion were used to assess COP and ICP. Magnetic resonance imaging measurements were performed to evaluate cerebral edema and infarct size. Evans blue was used to assess the blood­brain barrier (BBB) permeability. Western blotting was used to determine the expression levels of the tight junction proteins in cerebral vascular endothelial cells. The results showed that 25% albumin treatment (1.25 g/kg) by intravenous injection elevated the COP of plasma but did not reduce the ICP in rats that had undergone ischemic stroke. Additionally, albumin did not reduce the infarct size and instead aggravated cerebral edema. Furthermore, the BBB permeability was increased by albumin. Concomitantly, albumin treatment significantly downregulated the expression of tight junction proteins (ZO­1, occludin, and claudin­5) in cerebral vascular endothelial cells. Tight junction protein expression was significantly upregulated when the cells were treated with an MMP­9 inhibitor (GM6001). These results suggest that albumin aggravates cerebral edema in rats with ischemic stroke by increasing BBB permeability.

Fisetin ameliorates cognitive impairment by activating mitophagy and suppressing neuroinflammation in rats with sepsis-associated encephalopathy.

BACKGROUND: Fisetin, the effective ingredient of the traditional Chinese medicine named Cotinus coggygria, is recommended to be active therapeutic in many disorders. However, its role in sepsis-associated encephalopathy (SAE) remains unclarified. METHODS: Cecal ligation and puncture (CLP) operation was performed to establish a rat model of SAE. Rats were grouped according to the surgery operation and fisetin administration. Cognitive impairment was assessed by Morris water maze test. Disruption of blood-brain barrier (BBB) integrity was detected by Evan's blue staining. The mitophagy, reactive oxygen species (ROS) generation, NLRP3 inflammasome activation, and pro-inflammatory cytokines levels were measured through western blot and double immunofluorescence labeling. A transmission electron microscope was applied for the observation of mitochondrial autophagosomes. RESULTS: Rats in the CLP group presented increased expression of IL-1R1, pNF-κB, TNF-α, and iNOS in microglial cells, indicating severe inflammation in the central nervous system (CNS). Nevertheless, there was no increase in BBB permeability. Meanwhile, NLRP3 inflammasome was activated in cerebral microvascular endothelial cells (CMECs), presented with an elevation of caspase-1 expression and IL-1ß secretion into CNS. In addition, we found fisetin significantly improved cognitive dysfunction in rats with SAE. Neuroprotective effects of fisetin might be associated with inhibition of neuroinflammation, represented with decreased expression of IL-1R1, pNF-κB, TNF-α, and iNOS in microglia. Furthermore, fisetin induced mitophagy, scavenged ROS, blocked NLRP3 inflammasome activation of CMECs, as evidenced by decreased expression of caspase-1 and reduced release of IL-1ß into CNS. CONCLUSION: Collectively, fisetin-blocked NLRP3 inflammasome activation via promoting mitophagy in CMECs may suppress the secretion of IL-1ß into CNS, reduce neuroinflammation, and contribute to the amelioration of cognitive impairment.

Exosome-Derived lncRNA NEAT1 Exacerbates Sepsis-Associated Encephalopathy by Promoting Ferroptosis Through Regulating miR-9-5p/TFRC and GOT1 Axis.

Sepsis can cause sepsis-associated encephalopathy (SAE), but whether SAE was induced or exacerbated by ferroptosis remains unknown. In this study, the rat sepsis model was constructed using the cecal ligation and puncture method. The blood-brain barrier (BBB) permeability was measured by Evans blue dye (EBD) in vivo. The levels of ROS, Fe ion, MDA, GSH, and GPX4 were assessed by enzyme-linked immunosorbent assay (ELISA). The exosomes isolated from serum were cultured with bEnd.3 cells for the in vitro analysis. Moreover, bEnd.3 cells cultured with 100 µM FeCl3 (iron-rich) were to simulate ferroptosis stress. The cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay. A dual-luciferase reporter gene assay was performed to confirm the relationship between miR-9-5p with NEAT1, TFRC, and GOT1. In vivo, it is found that BBB permeability was damaged in model rats. Level of ROS, Fe ion, and MDA was increased, and level of GSH and GPX4 was decreased, which means ferroptosis was induced by sepsis. Exosome-packaged NEAT1 in serum was significantly upregulated in model rats. In vitro, it is found that NEAT1 functions as a ceRNA for miR-9-5p to facilitate TFRC and GOT1 expression. Overexpression of NEAT1 enhanced ferroptosis stress in bEnd.3 cells. Increased miR-9-5p alleviated sepsis-induced ferroptosis by suppressing the expression of TFRC and GOT1 both in vivo and in vitro. In conclusion, these findings suggest that sepsis induced high expression of serous exosome-derived NEAT1, and it might exacerbate SAE by promoting ferroptosis through regulating miR-9-5p/TFRC and GOT1 axis.

Elevated intracranial pressure induces IL­1ß and IL­18 overproduction via activation of the NLRP3 inflammasome in microglia of ischemic adult rats.

Elevated intracranial pressure (ICP) is one of the most common complications following an ischemic stroke, and has implications for the clinical and neurological outcomes. The aim of the present study was to examine whether elevated ICP may increase IL­1ß and IL­18 secretion by activating the NOD­like receptor protein 3 (NLRP3) inflammasome in microglia of ischemic adult rats. Sprague­Dawley rats that underwent middle cerebral artery occlusion were used for assessment of ICP. Reactive oxygen species (ROS) production was detected, and western blotting and immunofluorescence staining were used to determine the expression levels of Caspase­1, gasdermin D­N domains (GSDMD­N), IL­1ß and IL­18 in microglial cells. ICP levels were significantly increased, which was accompanied by ROS overproduction, in the brain tissue following ischemia­reperfusion (IR) injury in rats. Treatment with 10% hypertonic saline by intravenous injection significantly reduced the ICP and ROS levels of the rats. Furthermore, high pressure (20 mmHg) combined with oxygen­glucose deprivation (OGD) treatment resulted in increased ROS production in BV­2 microglial cells compared with those subjected to OGD treatment alone in vitro. Elevated pressure upregulated the expression of Caspase­1, GSDMD­N, IL­18 and IL­1ß in IR­treated or OGD­treated microglia both in vivo and in vitro. More importantly, Caspase­1, GSDMD­N, IL­18 and IL­1ß expression in microglia was significantly downregulated when elevated pressure was reduced or removed. These results suggested that elevated ICP­induced IL­1ß and IL­18 overproduction via activation of the NLRP3 inflammasome by ischemia­activated microglia may augment neuroinflammation.

Incidence and detection of high microsatellite instability in colorectal cancer in a Chinese population: a meta-analysis.

BACKGROUND: The 4 most common types of DNA mutations in tumors are single-nucleotide variations, insertion-deletion, fusion, and copy number variations. This is followed by microsatellite instability (MSI), which is known to trigger the development of MSI-high (MSI-H) cancer and is responsible for 300,000 new cases of cancer per year in China. We aim to conduct a meta-analysis based on a comparison between the positive rates of the National Cancer Institute (NCI) panel (also known as 2B3D NCI panel) and mononucleotide panels for the diagnosis of MSI in the Chinese population. METHODS: In the present meta-analysis, we searched the PubMed, Embase, Web of Science, CNKI, Wanfang, CQVIP, and CBM databases. MSI diagnosis studies by PCR and capillary electrophoresis were included to compare the incidence of MSI-H in colorectal cancer obtained from panels with different microsatellite markers. Egger's bias test was used to assess risk of bias. RESULTS: Seventeen articles were included, which used the Newcastle-Ottawa Scale (NOS) scale for quality evaluation. The NOS scores of the included documents were ≥7 points, and the quality of the documents met the requirements. The incidence of MSI-H detected by the 2B3D NCI panel was 13.5% [95% confidence interval (CI): 10.8-16.4, I2=52.321%, P=0.026, n=10 studies including 2,681 participants], the incidence of MSI-H detected by the mononucleotide panels was 10.6% (95% CI: 7.1-14.7, I2=81.147%, P=0.000, n=7 studies including 3,249 participants). This indicates that, in the Chinese population, the 2B3D NCI panel can detect 27.4% more MSI-H cancers than the mononucleotide panels, 54.7% more MSI-H cancers than the panel of 6 mononucleotides, and its sensitivity is comparable to that of Promega. CONCLUSIONS: The findings of the meta-analysis demonstrated that, using the 2B3D NCI panel for MSI detection can avoid the underestimation of the incidence MSI-H in colorectal cancer and can be considered the most suitable panel for MSI detection in the Chinese population. The inclusion of only published data might be a potential source of publication bias.

[Effect of hypercapnia on the clinical prognosis and severity of infection in patients with severe community-acquired pneumonia].

OBJECTIVE: To investigate the effect of hypercapnia at admission on the clinical prognosis and the severity of infection in patients with severe community-acquired pneumonia (SCAP). METHODS: The clinical data of 219 SCAP patients admitted to the department of emergency and critical care medicine of Guangdong Provincial People's Hospital from December 2017 to November 2019 were retrospectively analyzed. Based on the partial pressure of arterial carbon dioxide (PaCO2) within 1 day after admission, the patients were divided into hypocapnia group [HO group, PaCO2 < 35 mmHg (1 mmHg = 0.133 kPa)], normal carbonation group (NC group, PaCO2 35-45 mmHg) and hypercapnia group (HC group, PaCO2 > 45 mmHg). The clinical parameters of patients, such as gender, age, underlying diseases, white blood cell (WBC), procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6), pH value and lactate (Lac) within 1 day after admission were reviewed. The oxygenation index (PaO2/FiO2), pneumonia severity index (PSI) score and acute physiology and chronic health evaluation II (APACHE II) score were evaluated. The change tendencies of each index on day 1, day 3, and day 5 after admission were observed subsequently. Meanwhile, the rate of invasive mechanical ventilation (IMV), length of hospital stays and 28-day mortality among three groups were compared. Kaplan-Meier survival analysis was performed to assess the 28-day cumulative survival rate of patients with SCAP among three groups. Multivariate Logistic regression analysis was used to screen the risk factors of IMV and 28-day death in patients with SCAP. RESULTS: Compared with the HO group (n = 68) and NC group (n = 72), the HC group (n = 79) had higher proportion of preexisting comorbid chronic obstructive pulmonary disease (COPD) and PSI score, lower PCT, CRP, IL-6, and pH values. Compared with the HO group and NC group, there were smaller improvement trends on the levels of WBC, PCT, CRP, IL-6, PaO2/FiO2 and Lac at day 3 and day 5 as compared with day 1 in the HC group. On the 5th day after admission, the levels of WBC, PCT, CRP, IL-6, and Lac in the HC group were significantly higher than those in the HO group and NC group [WBC (×109/L): 18.33±1.44 vs. 10.89±2.37, 11.15±1.74; PCT (µg/L): 5.04±1.18 vs. 3.46±0.87, 3.58±0.83; CRP (mg/L): 78.43±7.17 vs. 54.24±4.97, 57.93±5.39; IL-6 (ng/L): 75.35±11.92 vs. 60.11±10.27, 57.88±12.34; Lac (mmol/L): 4.36±1.24 vs. 0.78±0.39, 0.86±0.64; all P < 0.01], and the lowest in PaO2/FiO2 was found in the HC group as compared with the HO and NC groups (mmHg: 171.31±6.73 vs. 226.68±7.36, 225.93±6.92, both P < 0.01). Compared with the HO group and NC group, the HC group had highest proportion of IMV (29.1% vs. 22.1%, 22.2%, both P < 0.01) and 28-day mortality (26.6% vs. 13.2%, 13.9%, both P < 0.01). Even when the patients with COPD were excluded from the analysis, the differences persisted among the groups. Kaplan-Meier survival analysis suggested that HC group had a higher 28-day cumulative survival rate as compared with the HO and NC groups (Log-Rank test: χ12 = 4.976, P1 = 0.026; χ22 = 4.629, P2 = 0.031). Multivariate Logistic regression analysis showed that IL-6, PSI score and hypercapnia within 1 day and PCT on the 5th day after admission were the independent risk factors of requiring IMV and 28-day death in patients with SCAP [odds ratio (OR) were 0.325, 1.229, 1.396, 1.313, respectively, all P < 0.01]. Even when patients with COPD were excluded from the analysis, the above results had not been changed. CONCLUSIONS: Hypercapnia at admission was associated with higher proportion of IMV and 28-day mortality in patients with SCAP, which may be related to its early suppression of inflammation and then increment of infection.

Single-cell transcriptomics reveals the alteration of peripheral blood mononuclear cells driven by sepsis.

BACKGROUND: Sepsis is a serious systemic inflammatory response syndrome caused by infection, with an extremely high mortality rate. Peripheral blood mononuclear cells (PBMCs) played a key role in the immune response against infection, whose components and functions were altered radically in Sepsis. Here, we wondered to characterize the alteration of PBMCs in sepsis at the single-cell transcriptional level. METHODS: We isolated PBMCs from seven septic patients and four donors. Based on BD Rhapsody, PBMCs were generated by single-cell RNA sequencing, and cell types were clustered and named by unsupervised clustering and annotation analysis. RESULTS: PBMCs were profiled for 6 kinds of cell types, the biological properties of T cell and monocytes were shown in a detailed manner. We noticed that monocytes could be clustered into 6 subsets, with great heterogeneity in the alteration of composition, gene profile, and signaling pathways driven by sepsis. Moreover, the expression of representative genes was high associated with septic clinical indicators in clusters of monocytes, such as NEAT1. CONCLUSIONS: Although the study was preliminary, we revealed sepsis-specific alteration of PBMCs and associated pathways. These results give a panoramic picture of PBMCs in composition, genes profiles, and pathway signatures that are driven by sepsis, which offers a unique perspective to understand disease progression or treatment in clinical practice.

Effects of dexmedetomidine on heart rate control and pre-operative outcome in patients with acute aortic dissection: a propensity-matched analysis.

BACKGROUND: The total survival rate in patients with acute aortic dissection (AAD) has been greatly improved because of surgical technique advances. However, the pre-operative mortality rate remained high. In this study, we sought to evaluate the effects of dexmedetomidine (DEX) on heart rate control and preoperative outcome in AAD. METHODS: Retrospectively enrolled 461 patients who were diagnosed with AAD during the first 7-day after admission and divided into two groups according to the use of intravenous DEX: DEX group (91 patients) and Control group (370 patients). The heart rate and systolic blood pressure (SBP) level in both groups were recorded, and the incidence of aortic dissection rupture and pre-operative survival rates within 7 days were considered as the primary clinical outcomes. RESULTS: Compared to the Control group, heart rate of DEX group in the early 3 hours was significantly higher (P=0.009), and the 24-hour heart rate fluctuation was smaller (P=0.012). There was no difference in the systolic blood pressure (SBP) between the two groups, but the 24-hour fluctuation of SBP in DEX group was less (P=0.003). We performed a propensity-matched analysis to minimize selection bias and found that there were 7 (7.9%) patients in the DEX group occurred acute pulmonary edema, 17 (19.1%) patients in the Control group (P=0.047). And the pre-operative survival rates within 7 days were significantly improved in DEX group (P=0.004). And the pre-operative survival rates within 7 days were significantly improved in DEX group (P=0.004). CONCLUSIONS: DEX can be beneficial to facilitate heart rate control, keep SBP more steady, and reduce the incidence of pre-operative aortic rupture in patients with AAD.

Maf1 Ameliorates Sepsis-Associated Encephalopathy by Suppressing the NF-kB/NLRP3 Inflammasome Signaling Pathway.

Background: The NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome has been identified as an important mediator of blood-brain-barrier disruption in sepsis-associated encephalopathy (SAE). However, no information is available concerning the critical upstream regulators of SAE. Methods: Lipopolysaccharide (LPS) was used to establish an in vitro model of blood-brain barrier (BBB) disruption and an in vivo model of SAE. Disruption of BBB integrity was assessed by measuring the expression levels of tight-junction proteins. NLRP3 inflammasome activation, pro-inflammatory cytokines levels, and neuroapoptosis were measured using biochemical assays. Finally, the FITC-dextran Transwell assay and Evan's blue dye assay were used to assess the effect of Maf1 on LPS-induced endothelial permeability in vitro and in vivo. Results: We found that Maf1 significantly suppressed the brain inflammatory response and neuroapoptosis induced by LPS in vivo and in vitro. Notably, Maf1 downregulated activation of the NF-κB/p65-induced NLRP3 inflammasome and the expression of pro-inflammatory cytokines. In addition, we found that Maf1 and p65 directly bound to the NLRP3 gene promoter region and competitively regulated the function of NLRP3 in inflammations. Moreover, overexpression of NLRP3 reversed the effects of p65 on BBB integrity, apoptosis, and inflammation in response to LPS. Our study revealed novel role for Maf1 in regulating NF-κB-mediated inflammasome formation, which plays a prominent role in SAE. Conclusions: Regulation of Maf1 might be a therapeutic strategy for SAE and other neurodegenerative diseases associated with inflammation.