Sepsis sensitizes behavioural amphetamine responses while inducing inflammatory and neurotrophic vulnerability in the cecal ligation and puncture model.

The present study aimed to evaluate if sepsis sensitizes behavioural and biochemical responses induced by m-amphetamine. For this, Wistar rats were submitted to the cecal ligation and puncture. After 30 days of cecal ligation and puncture procedure, the animals were submitted to a single intraperitoneal injection of saline or m-amphetamine (.25, .50, or 1.0 mg/kg). Locomotor behaviour was assessed 2 h after the administration. Interleukin (IL)-1ß, IL-6, IL-10, tumour necrosis factor-α, dopamine-cAMP-regulated phosphoprotein of 32,000 kDa (DARPP-32) and neuronal calcium sensor (NCS-1) levels were evaluated in the frontal cortex, hippocampus and striatum. Also, brain-derived neurotrophic factor (BDNF), neuronal growth factor and glial-derived neurotrophic factor levels were assessed in the hippocampus. M-amphetamine alone (.25 and 1.0 mg/kg) increased rats' locomotion and exploratory behaviour compared with the Sham + Sal. Animals from the cecal ligation and puncture + m-amphetamine (.5 and/or 1.0 mg/kg) group showed an increase in locomotion, exploratory and risk-like behaviour when compared with the Sham + Saline group and with its respective Sham groups. Cecal ligation and puncture increased interleukin levels compared with the Sham + Sal. However, cecal ligation and puncture animals that received m-amphetamine (1 mg/kg) increased even more, these inflammatory parameters compared with the Sham + Sal and the cecal ligation and puncture + saline group. M-amphetamine at lower doses increased neurotrophic factors, but higher doses decreased these parameters in the brain of cecal ligation and puncture rats. M-amphetamine dose-dependently increased DARPP-32 and NCS-1 levels in cecal ligation and puncture rats in some structures. In conclusion, these results demonstrate that sepsis sensitizes behavioural amphetamine responses while inducing inflammatory and neurotrophic vulnerability in the cecal ligation and puncture model.

Sepsis exacerbates Alzheimer's disease pathophysiology, modulates the gut microbiome, increases neuroinflammation and amyloid burden.

While our understanding of the molecular biology of Alzheimer's disease (AD) has grown, the etiology of the disease, especially the involvement of peripheral infection, remains a challenge. In this study, we hypothesize that peripheral infection represents a risk factor for AD pathology. To test our hypothesis, APP/PS1 mice underwent cecal ligation and puncture (CLP) surgery to develop a polymicrobial infection or non-CLP surgery. Mice were euthanized at 3, 30, and 120 days after surgery to evaluate the inflammatory mediators, glial cell markers, amyloid burden, gut microbiome, gut morphology, and short-chain fatty acids (SCFAs) levels. The novel object recognition (NOR) task was performed 30 and 120 days after the surgery, and sepsis accelerated the cognitive decline in APP/PS1 mice at both time points. At 120 days, the insoluble Aß increased in the sepsis group, and sepsis modulated the cytokines/chemokines, decreasing the cytokines associated with brain homeostasis IL-10 and IL-13 and increasing the eotaxin known to influence cognitive function. At 120 days, we found an increased density of IBA-1-positive microglia in the vicinity of Aß dense-core plaques, compared with the control group confirming the predictable clustering of reactive glia around dense-core plaques within 15 µm near Aß deposits in the brain. In the gut, sepsis negatively modulated the α- and ß-diversity indices evaluated by 16S rRNA sequencing, decreased the levels of SCFAs, and significantly affected ileum and colon morphology in CLP mice. Our data suggest that sepsis-induced peripheral infection accelerates cognitive decline and AD pathology in the AD mouse model.

Nutritional strategies cause memory damage and alter biochemical parameters without causing neuroinflammation.

Obesity results from an energy imbalance and has been considered an epidemic due to its increasing rates worldwide. It is classified as a low-grade chronic inflammatory disease and has associated comorbidities. Different nutritional strategies are used for the purpose of weight loss, highlighting low-carbohydrate (LC) diets, ketogenic diets, and intermittent fasting (IF). These strategies can lead to metabolic and behavioral changes as they stimulate different biochemical pathways. Therefore, this study evaluated memory, energy metabolism, neuroinflammation, oxidative stress, and antioxidant defense parameters in mice subjected to an LC diet, ketogenic diet (KD), or IF. Eighty male Swiss mice, 60 days old, were divided into 4 groups: control, LC, KD, or IF. Body weight was measured weekly, and food intake every 48 h. After 15 days of nutritional interventions, the animals were subjected to the behavioral object recognition test and subsequently euthanized. Then, visceral fat was removed and weighed, and the brain was isolated for inflammatory and biochemical analysis. We concluded from this study that the LC and KD strategies could damage memory, IF improves the production of adenosine triphosphate (ATP), and the LC, KD, and IF strategies do not lead to neuroinflammatory damage but present damage at the level of oxidative stress.

Enoxaparin improves COVID-19 by reducing Neutrophils Extracellular Traps (NETs) production.

BACKGROUND: COVID-19 causes consequences such as imbalance of the immune system and thrombotic events. During the infection process, NETs in excess induce a pro-inflammatory response and disseminated intravascular coagulation. We evaluated the role of enoxaparin as a potential inhibitor of NETs. METHODS: K18-hACE2 animals infected with the SARS-CoV-2 virus and a group of 23 individuals admitted to the hospital with COVID-19 treated with enoxaparin or without treatment and controls without the disease were included. RESULTS: Enoxaparin decreased the levels of NETs, reduced the signs of the disease and mitigated lung damage in the animals infected with SARS-CoV-2. These effects were partially associated with prevention of SARS-CoV-2 entry and NETs synthesis. Clinical data revealed that treatment with enoxaparin decreased the levels of inflammatory markers, the levels of NETs in isolated neutrophils and the organ dysfunction. CONCLUSION: This study provides evidence for the beneficial effects of enoxaparin in COVID-19 in addition to its anticoagulant role.

Neurochemical effects of sepsis on the brain.

Sepsis is a life-threatening organ dysfunction triggered by a dysregulated host immune response to eliminate an infection. After the host immune response is activated, a complex, dynamic, and time-dependent process is triggered. This process promotes the production of inflammatory mediators, including acute-phase proteins, complement system proteins, cytokines, chemokines, and antimicrobial peptides, which are required to initiate an inflammatory environment for eliminating the invading pathogen. The physiological response of this sepsis-induced systemic inflammation can affect blood-brain barrier (BBB) function; subsequently, endothelial cells produce inflammatory mediators, including cytokines, chemokines, and matrix metalloproteinases (MMPs) that degrade tight junction (TJ) proteins and decrease BBB function. The resulting BBB permeability allows peripheral immune cells from the bloodstream to enter the brain, which then release a range of inflammatory mediators and activate glial cells. The activated microglia and astrocytes release reactive oxygen species (ROS), cytokines, chemokines, and neurochemicals, initiate mitochondrial dysfunction and neuronal damage, and exacerbate the inflammatory milieu in the brain. These changes trigger sepsis-associated encephalopathy (SAE), which has the potential to increase cognitive deterioration and susceptibility to cognitive decline later in life.

Paraprobiotics strains accelerate wound repair by stimulating re-epithelialization of NIH-3T3 cells, decreasing inflammatory response and oxidative stress.

The present study aimed to evaluate the potential and specificity of the inflammatory and antioxidant response of Microbe-Associated Molecular Patterns (MAMPs) in NIH-3T3 fibroblast cells, as well as in the healing process of skin wounds. Cells (NIH-3T3) were cultivated in supplemented specific medium. NIH-3T3 cells were treated with MAMPs (Bifidobacterium lactis or Lactobacillus casei or Lactobacillus gasseri or Lactobacillus paracasei or Streptococcus thermophilus), at two concentrations and insulted with LPS or H2O2. Cell viability, myeloperoxidase activity, nitrite/nitrate, oxidative damage and inflammatory parameters were measured. In addition, scratch assay was performed. Significant scratch closure was observed after 24 h and 48 h, and the effect of 0.1 g/mL MAMPs on wound healing was found to be highly statistically significant. In the viability cellular assay, Lactobacillus showed better response in 0.1 g/mL dose, whereas B. lactis and S. thermophilus showed better response in 0.01 g/mL dose. There was reduction in IL-6 and IL-1ß levels in all treatments insulted with LPS. MAMP's showed preventive efficacy in reducing the effects caused by LPS. The MAMP's action in decreasing the production of ROS, inflammatory activity and increasing cell viability, besides significant cell proliferation during wound healing processes suggests remodeling mechanisms and new possibilities for wound healing.

Coagulation biomarkers and coronavirus disease 2019 phenotyping: a prospective cohort study.

BACKGROUND: Because severe acute respiratory syndrome coronarivus 2 (SARS-CoV-2) leads to severe conditions and thrombus formation, evaluation of the coagulation markers is important in determining the prognosis and phenotyping of patients with COVID-19. METHODS: In a prospective study that included 213 COVID-19 patients admitted to the intensive care unit (ICU) the levels of antithrombin, C-reactive protein (CRP); factors XI, XII, XIII; prothrombin and D-dimer were measured. Spearman's correlation coefficient was used to assess the pairwise correlations between the biomarkers. Hierarchical and non-hierarchical cluster analysis was performed using the levels of biomarkers to identify patients´ phenotypes. Multivariate binary regression was used to determine the association of the patient´s outcome with clinical variables and biomarker levels. RESULTS: The levels of factors XI and XIII were significantly higher in patients with less severe COVID-19, while factor XIII and antithrombin levels were significantly associated with mortality. These coagulation biomarkers were associated with the in-hospital survival of COVID-19 patients over and above the core clinical factors on admission. Hierarchical cluster analysis showed a cluster between factor XIII and antithrombin, and this hierarchical cluster was extended to CRP in the next step. Furthermore, a non-hierarchical K-means cluster analysis was performed, and two phenotypes were identified based on the CRP and antithrombin levels independently of clinical variables and were associated with mortality. CONCLUSION: Coagulation biomarkers were associated with in-hospital survival of COVID-19 patients. Lower levels of factors XI, XII and XIII and prothrombin were associated with disease severity, while higher levels of both CRP and antithrombin clustered with worse prognosis. These results suggest the role of coagulation abnormalities in the development of COVID-19 and open the perspective of identifying subgroups of patients who would benefit more from interventions focused on regulating coagulation.

Bacillus strains prevent lipopolysaccharide-induced inflammation in gut and blood of male mice.

AIMS: The protective effects of Bacillus amyloliquefaciens(CCT7935), Bacillus subtilis(CCT7935), Bacillus licheniformis (CCT 7836), and Bacillus coagulans (CCT 0199) against lipopolysaccharide (LPS)-induced intestinal inflammation were investigated. METHODS AND RESULTS: Male Swiss mice were assigned into six groups: control group, LPS group, LPS + B. subtilis (CCT7935) group, LPS +   B. licheniformis (CCT 7836) group, LPS +   B. amyloliquefaciens (CCT7935) group, and LPS   + B. coagulans (CCT 0199) group. Each mouse of the groups Bacillus received 1 × 109 colony-forming units of Bacillus once daily by oral gavage during 30 days. Twenty-four hours after the last dose of Bacillus, all groups, except the control group, were intraperitoneally injected with LPS in the single dose of 15 mg kg-1. The mice were euthanized 24 h after the LPS administration. Histological alterations, myeloperoxidase activity, and nitrite levels were analyzed in the gut of mice and the inflammatory cytokines were analyzed in the gut and in the blood. The results demonstrate that the mice challenged with LPS presented the villi shortened and damaged, which were significantly protected by B. coagulans and B. amyloliquefaciens. Furthermore, all Bacillus tested were effective in preventing against the increase of myeloperoxidase activity, while B. amyloliquefaciens and B. subtilis prevented the increase of nitrite and IL-1ß levels in the gut of mice induced with LPS was decreased only B. subtilis. LPS also elevated the IL-1 ß, IL-6, and IL-10 levels in the blood, and these alterations were significantly suppressed by Bacillus, especially by B. subtilis. CONCLUSIONS: The study suggests that the Bacillus investigated in this study might be effective therapeutic agents for preventing intestinal inflammation, because they decrease the inflammatory process an protect against tissue damage.

Neurological impairment caused by Schistosoma mansoni systemic infection exhibits early features of idiopathic neurodegenerative disease.

Schistosomiasis, a neglected tropical disease caused by trematodes of the Schistosoma genus, affects over 250 million people around the world. This disease has been associated with learning and memory deficits in children, whereas reduced attention levels, impaired work capacity, and cognitive deficits have been observed in adults. Strongly correlated with poverty and lack of basic sanitary conditions, this chronic endemic infection is common in Africa, South America, and parts of Asia and contributes to inhibition of social development and low quality of life in affected areas. Nonetheless, studies on the mechanisms involved in the neurological impairment caused by schistosomiasis are scarce. Here, we used a murine model of infection with Schistosoma mansoni in which parasites do not invade the central nervous system to evaluate the consequences of systemic infection on neurologic function. We observed that systemic infection with S. mansoni led to astrocyte and microglia activation, expression of oxidative stress-induced transcription factor Nrf2, oxidative damage, Tau phosphorylation, and amyloid-ß peptide accumulation in the prefrontal cortex of infected animals. We also found impairment in spatial learning and memory as evaluated by the Morris water maze task. Administration of anthelmintic (praziquantel) and antioxidant (N-acetylcysteine plus deferoxamine) treatments was effective in inhibiting most of these phenotypes, and the combination of both treatments had a synergistic effect to prevent such changes. These data demonstrate new perspectives toward the understanding of the pathology and possible therapeutic approaches to counteract long-term effects of systemic schistosomiasis on brain function.

Mitochondrial protective effects caused by the administration of mefenamic acid in sepsis.

The pathophysiology of sepsis may involve the activation of the NOD-type receptor containing the pyrin-3 domain (NLPR-3), mitochondrial and oxidative damages. One of the primary essential oxidation products is 8-oxoguanine (8-oxoG), and its accumulation in mitochondrial DNA (mtDNA) induces cell dysfunction and death, leading to the hypothesis that mtDNA integrity is crucial for maintaining neuronal function during sepsis. In sepsis, the modulation of NLRP-3 activation is critical, and mefenamic acid (MFA) is a potent drug that can reduce inflammasome activity, attenuating the acute cerebral inflammatory process. Thus, this study aimed to evaluate the administration of MFA and its implications for the reduction of inflammatory parameters and mitochondrial damage in animals submitted to polymicrobial sepsis. To test our hypothesis, adult male Wistar rats were submitted to the cecal ligation and perforation (CLP) model for sepsis induction and after receiving an injection of MFA (doses of 10, 30, and 50 mg/kg) or sterile saline (1 mL/kg). At 24 h after sepsis induction, the frontal cortex and hippocampus were dissected to analyze the levels of TNF-α, IL-1ß, and IL-18; oxidative damage (thiobarbituric acid reactive substances (TBARS), carbonyl, and DCF-DA (oxidative parameters); protein expression (mitochondrial transcription factor A (TFAM), NLRP-3, 8-oxoG; Bax, Bcl-2 and (ionized calcium-binding adaptor molecule 1 (IBA-1)); and the activity of mitochondrial respiratory chain complexes. It was observed that the septic group in both structures studied showed an increase in proinflammatory cytokines mediated by increased activity in NLRP-3, with more significant oxidative damage and higher production of reactive oxygen species (ROS) by mitochondria. Damage to mtDNA it was also observed with an increase in 8-oxoG levels and lower levels of TFAM and NGF-1. In addition, this group had an increase in pro-apoptotic proteins and IBA-1 positive cells. However, MFA at doses of 30 and 50 mg/kg decreased inflammasome activity, reduced levels of cytokines and oxidative damage, increased bioenergetic efficacy and reduced production of ROS and 8-oxoG, and increased levels of TFAM, NGF-1, Bcl-2, reducing microglial activation. As a result, it is suggested that MFA induces protection in the central nervous system early after the onset of sepsis.

A crosstalk between gut and brain in sepsis-induced cognitive decline.

BACKGROUND: Sepsis is a potentially fatal disease characterized by acute organ failure that affects more than 30 million people worldwide. Inflammation is strongly associated with sepsis, and patients can experience impairments in memory, concentration, verbal fluency, and executive functioning after being discharged from the hospital. We hypothesize that sepsis disrupts the microbiota-gut-brain axis homeostasis triggering cognitive impairment. This immune activation persists during treatment, causing neurological dysfunction in sepsis survivors. METHODS: To test our hypothesis, adult Wistar rats were subjected to cecal-ligation and perforation (CLP) or sham (non-CLP) surgeries. The animals were subjected to the [11C]PBR28 positron emission tomography (PET)/computed tomography (CT) imaging at 24 h and 10 days after CLP and non-CLP surgeries. At 24 h and 10 days after surgery, we evaluated the gut microbiome, bacterial metabolites, cytokines, microglia, and astrocyte markers. Ten days after sepsis induction, the animals were subjected to the novel object recognition (NOR) and the Morris water maze (MWM) test to assess their learning and memory. RESULTS: Compared to the control group, the 24-h and 10-day CLP groups showed increased [11C]PBR28 uptake, glial cells count, and cytokine levels in the brain. Results show that sepsis modulates the gut villus length and crypt depth, alpha and beta microbial diversities, and fecal short-chain fatty acids (SCFAs). In addition, sepsis surviving animals showed a significant cognitive decline compared with the control group. CONCLUSIONS: Since several pharmacological studies have failed to prevent cognitive impairment in sepsis survivors, a better understanding of the function of glial cells and gut microbiota can provide new avenues for treating sepsis patients.

Postmortem Evidence of Brain Inflammatory Markers and Injury in Septic Patients: A Systematic Review.

OBJECTIVES: Sepsis is a life-threatening organ dysfunction caused by a host's unregulated immune response to eliminate the infection. After hospitalization, sepsis survivors often suffer from long-term impairments in memory, attention, verbal fluency, and executive functioning. To understand the effects of sepsis and the exacerbated peripheral inflammatory response in the brain, we asked the question: What are the findings and inflammatory markers in the brains of deceased sepsis patients? To answer this question, we conducted this systematic review by the recommendations of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. DATA SOURCES: Relevant studies were identified by searching the PubMed/National Library of Medicine, PsycINFO, EMBASE, Bibliographical Index in Spanish in Health Sciences, Latin American and Caribbean Health Sciences Literature, and Web of Science databases for peer-reviewed journal articles published on April 05, 2021. STUDY SELECTION: A total of 3,745 articles were included in the primary screening; after omitting duplicate articles, animal models, and reviews, 2,896 articles were selected for the study. These studies were selected based on the title and abstract, and 2,772 articles were still omitted based on the exclusion criteria. DATA EXTRACTION: The complete texts of the remaining 124 articles were obtained and thoroughly evaluated for the final screening, and 104 articles were included. DATA SYNTHESIS: The postmortem brain had edema, abscess, hemorrhagic and ischemic injuries, infarction, hypoxia, atrophy, hypoplasia, neuronal loss, axonal injuries, demyelination, and necrosis. CONCLUSIONS: The mechanisms by which sepsis induces brain dysfunction are likely to include vascular and neuronal lesions, followed by the activation of glial cells and the presence of peripheral immune cells in the brain.

Detailed Characterization of Brain Dysfunction in a Long-Term Rodent Model of Critical Illness.

Critical illness encompasses a wide spectrum of life-threatening clinical conditions requiring intensive care. Our objective was to evaluate cognitive, inflammatory and cellular metabolism alterations in the central nervous system in an animal model of critical illness induced by zymosan. For this Wistar rats that were divided into Sham and zymosan. Zymozan was administered once intraperitoneally (30 g/100 g body weight) diluted in mineral oil. The animals were submitted to behavioral tests of octagonal maze, inhibitory avoidance and elevated plus maze. Brain structures (cortex, prefrontal and hippocampus) were removed at 24 h, 4, 7 and 15 days after zymosan administration for analysis of cytokine levels (TNF-α, IL-1b, IL-6 and IL-10), oxidative damage and oxygen consumption. Zymosan-treated animals presented mild cognitive impairment both in aversive (inhibitory avoidance) and non-aversive (octagonal maze) tasks by day 15. However, they did not show increase in anxiety (elevated-plus maze). The first neurochemical alteration found was an increase in brain pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α) at day 4th in the hippocampus. In cortex, a late (7 and 15 days) increase in TNF-α was also noted, while the anti-inflammatory cytokine IL-10 decrease from 4 to 15 days. Oxygen consumption was decreased in the hippocampus and pre-frontal, but not cortex, only at 7 days. Additionally, it was observed a late (15 days) increase in oxidative damage parameters. This characterization of brain dysfunction in rodent model of critical illness reproduces some of the alterations reported in humans such neuropsychiatric disorders, especially depression, memory loss and cognitive changes and can add to the nowadays used models.

Biomarkers for sepsis: more than just fever and leukocytosis-a narrative review.

A biomarker describes a measurable indicator of a patient's clinical condition that can be measured accurately and reproducibly. Biomarkers offer utility for diagnosis, prognosis, early disease recognition, risk stratification, appropriate treatment (theranostics), and trial enrichment for patients with sepsis or suspected sepsis. In this narrative review, we aim to answer the question, "Do biomarkers in patients with sepsis or septic shock predict mortality, multiple organ dysfunction syndrome (MODS), or organ dysfunction?" We also discuss the role of pro- and anti-inflammatory biomarkers and biomarkers associated with intestinal permeability, endothelial injury, organ dysfunction, blood-brain barrier (BBB) breakdown, brain injury, and short and long-term mortality. For sepsis, a range of biomarkers is identified, including fluid phase pattern recognition molecules (PRMs), complement system, cytokines, chemokines, damage-associated molecular patterns (DAMPs), non-coding RNAs, miRNAs, cell membrane receptors, cell proteins, metabolites, and soluble receptors. We also provide an overview of immune response biomarkers that can help identify or differentiate between systemic inflammatory response syndrome (SIRS), sepsis, septic shock, and sepsis-associated encephalopathy. However, significant work is needed to identify the optimal combinations of biomarkers that can augment diagnosis, treatment, and good patient outcomes.

Airway inflammation induces anxiety-like behavior through neuroinflammatory, neurochemical, and neurometabolic changes in an allergic asthma model.

Allergic asthma is characterized by chronic airway inflammation and is constantly associated with anxiety disorder. Recent studies showed bidirectional interaction between the brain and the lung tissue. However, where and how the brain is affected in allergic asthma remains unclear. We aimed to investigate the neuroinflammatory, neurochemical, and neurometabolic alterations that lead to anxiety-like behavior in an experimental model of allergic asthma. Mice were submitted to an allergic asthma model induced by ovalbumin (OVA) and the control group received only Dulbecco's phosphate-buffered saline (DPBS). Our findings indicate that airway inflammation increases interleukin (IL) -9, IL-13, eotaxin, and IL-1ß release and changes acetylcholinesterase (AChE) and Na+,K+-ATPase activities in the brain of mice. Furthermore, we demonstrate that a higher reactive oxygen species (ROS) formation and antioxidant defense alteration that leads to protein damage and mitochondrial dysfunction. Therefore, airway inflammation promotes a pro-inflammatory environment with an increase of BDNF expression in the brain of allergic asthma mice. These pro-inflammatory environments lead to an increase in glucose uptake in the limbic regions and to anxiety-like behavior that was observed through the elevated plus maze (EPM) test and downregulation of glucocorticoid receptor (GR). In conclusion, the present study revealed for the first time that airway inflammation induces neuroinflammatory, neurochemical, and neurometabolic changes within the brain that leads to anxiety-like behavior. Knowledge about mechanisms that lead to anxiety phenotype in asthma is a beneficial tool that can be used for the complete management and treatment of the disease.

Predictive Accuracy of the Quick Sepsis-related Organ Failure Assessment Score in Brazil. A Prospective Multicenter Study.

Rationale: Although proposed as a clinical prompt to sepsis based on predictive validity for mortality, the Quick Sepsis-related Organ Failure Assessment (qSOFA) score is often used as a screening tool, which requires high sensitivity.Objectives: To assess the predictive accuracy of qSOFA for mortality in Brazil, focusing on sensitivity.Methods: We prospectively collected data from two cohorts of emergency department and ward patients. Cohort 1 included patients with suspected infection but without organ dysfunction or sepsis (22 hospitals: 3 public and 19 private). Cohort 2 included patients with sepsis (54 hospitals: 24 public and 28 private). The primary outcome was in-hospital mortality. The predictive accuracy of qSOFA was examined considering only the worst values before the suspicion of infection or sepsis.Measurements and Main Results: Cohort 1 contained 5,460 patients (mortality rate, 14.0%; 95% confidence interval [CI], 13.1-15.0), among whom 78.3% had a qSOFA score less than or equal to 1 (mortality rate, 8.3%; 95% CI, 7.5-9.1). The sensitivity of a qSOFA score greater than or equal to 2 for predicting mortality was 53.9% and the 95% CI was 50.3 to 57.5. The sensitivity was higher for a qSOFA greater than or equal to 1 (84.9%; 95% CI, 82.1-87.3), a qSOFA score greater than or equal to 1 or lactate greater than 2 mmol/L (91.3%; 95% CI, 89.0-93.2), and systemic inflammatory response syndrome plus organ dysfunction (68.7%; 95% CI, 65.2-71.9). Cohort 2 contained 4,711 patients, among whom 62.3% had a qSOFA score less than or equal to 1 (mortality rate, 17.3%; 95% CI, 15.9-18.7), whereas in public hospitals the mortality rate was 39.3% (95% CI, 35.5-43.3).Conclusions: A qSOFA score greater than or equal to 2 has low sensitivity for predicting death in patients with suspected infection in a developing country. Using a qSOFA score greater than or equal to 2 as a screening tool for sepsis may miss patients who ultimately die. Using a qSOFA score greater than or equal to 1 or adding lactate to a qSOFA score greater than or equal to 1 may improve sensitivity.Clinical trial registered with www.clinicaltrials.gov (NCT03158493).

Immunomodulatory Effect of Bifidobacterium, Lactobacillus, and Streptococcus Strains of Paraprobiotics in Lipopolysaccharide-Stimulated Inflammatory Responses in RAW-264.7 Macrophages.

The discovery of the potential of paraprobiotics to exert different immunological benefits suggests that further studies should be carried out to determine their potential and mechanisms of action in modulating the immune system. The objective of this study was to investigate the immune response of several microbial-associated molecular patterns (MAMPS) used at different doses in macrophage cell lines RAW-264.7 stimulated with lipopolysaccharide (LPS). Two experiments were conducted. The first was performed to determine a dose response curve for each paraprobiotic (Bifidobacterium lactis, Lactobacillus casei, Lactobacillus gasseri, Lactobacillus paracasei, and Streptococcus thermophilus). Further experiments were carried using only two doses (0.01 g/ml and 0.1 g/ml). RAW-264.7 cells were cultivated in Dubelcco's Modified Eagle's medium supplemented with fetal bovine serum and penicillin/streptomycin. Cells were incubated with LPS (1 µg/ml) and six concentrations of MAMPs were added. RAW-264.7 viability, myeloperoxidase activity, nitrite/nitrate concentration, reactive oxygen species production, oxidative damage, and inflammatory parameters were measured. In the LPS group, there was a significant reduction in cell viability. Myeloperoxidase and nitrite/nitrate concentrations demonstrated a better effect at 0.01 and 0.1 g/ml doses. There was a significant reduction in interleukin-6 (IL-6) levels at 0.1 g/ml dose in all paraprobiotics. IL-10 levels decreased in the LPS group and increased at 0.1 g/ml dose in all paraprobiotics. The dichlorofluorescin diacetate results were reinforced by the observed in oxidative damage. Paraprobiotics are likely to contribute to the improvement of intestinal homeostasis, immunomodulation, and host metabolism.

Effect of Slower vs Faster Intravenous Fluid Bolus Rates on Mortality in Critically Ill Patients: The BaSICS Randomized Clinical Trial.

Importance: Slower intravenous fluid infusion rates could reduce the formation of tissue edema and organ dysfunction in critically ill patients; however, there are no data to support different infusion rates during fluid challenges for important outcomes such as mortality. Objective: To determine the effect of a slower infusion rate vs control infusion rate on 90-day survival in patients in the intensive care unit (ICU). Design, Setting, and Participants: Unblinded randomized factorial clinical trial in 75 ICUs in Brazil, involving 11 052 patients requiring at least 1 fluid challenge and with 1 risk factor for worse outcomes were randomized from May 29, 2017, to March 2, 2020. Follow-up was concluded on October 29, 2020. Patients were randomized to 2 different infusion rates (reported in this article) and 2 different fluid types (balanced fluids or saline, reported separately). Interventions: Patients were randomized to receive fluid challenges at 2 different infusion rates; 5538 to the slower rate (333 mL/h) and 5514 to the control group (999 mL/h). Patients were also randomized to receive balanced solution or 0.9% saline using a factorial design. Main Outcomes and Measures: The primary end point was 90-day survival. Results: Of all randomized patients, 10 520 (95.2%) were analyzed (mean age, 61.1 years [SD, 17.0 years]; 44.2% were women) after excluding duplicates and consent withdrawals. Patients assigned to the slower rate received a mean of 1162 mL on the first day vs 1252 mL for the control group. By day 90, 1406 of 5276 patients (26.6%) in the slower rate group had died vs 1414 of 5244 (27.0%) in the control group (adjusted hazard ratio, 1.03; 95% CI, 0.96-1.11; P = .46). There was no significant interaction between fluid type and infusion rate (P = .98). Conclusions and Relevance: Among patients in the intensive care unit requiring fluid challenges, infusing at a slower rate compared with a faster rate did not reduce 90-day mortality. These findings do not support the use of a slower infusion rate. Trial Registration: ClinicalTrials.gov Identifier: NCT02875873.

Characterization and modulation of microglial phenotypes in an animal model of severe sepsis.

We aim to characterize the kinetics of early and late microglial phenotypes after systemic inflammation in an animal model of severe sepsis and the effects of minocycline on these phenotypes. Rats were subjected to CLP, and some animals were treated with minocycline (10 ug/kg) by i.c.v. administration. Animals were killed 24 hours, 5, 10 and 30 days after sepsis induction, and serum and hippocampus were collected for subsequent analyses. Real-time PCR was performed for M1 and M2 markers. TNF-α, IL-1ß, IL-6, IL-10, CCL-22 and nitrite/nitrate levels were measured. Immunofluorescence for IBA-1, CD11b and arginase was also performed. We demonstrated that early after sepsis, there was a preponderant up-regulation of M1 markers, and this was not switched to M2 phenotype markers later on. We found that up-regulation of both M1 and M2 markers co-existed up to 30 days after sepsis induction. In addition, minocycline induced a down-regulation, predominantly, of M1 markers. Our results suggest early activation of M1 microglia that is followed by an overlap of both M1 and M2 phenotypes and that the beneficial effects of minocycline on sepsis-associated brain dysfunction may be related to its effects predominantly on the M1 phenotype.

Neuroinflammation trajectories precede cognitive impairment after experimental meningitis-evidence from an in vivo PET study.

BACKGROUND: Bacterial meningitis is a devastating central nervous system (CNS) infection with acute and long-term neurological consequences, including cognitive impairment. The aim of this study was to understand the association between activated microglia-induced neuroinflammation and post-meningitis cognitive impairment. METHOD: Meningitis was induced in male Wistar rats by injecting Streptococcus pneumoniae into the brain through the cisterna magna, and rats were then treated with ceftriaxone. Twenty-four hours and 10 days after meningitis induction, rats were imaged with positron emission tomography (PET) using [11C]PBR28, a specific translocator protein (TSPO) radiotracer, to determine in vivo microglial activation. Following imaging, the expression of TSPO, cardiolipin, and cytochrome c, inflammatory mediators, oxidative stress markers, and glial activation markers were evaluated in the prefrontal cortex and hippocampus. Ten days after meningitis induction, animals were subjected to behavioral tests, such as the open-field, step-down inhibitory avoidance, and novel object recognition tests. RESULTS: Both 24-h (acute) and 10-day (long-term) groups of rats demonstrated increased [11C]PBR28 uptake and microglial activation in the whole brain compared to levels in the control group. Although free from infection, 10-day group rats exhibited increased expression levels of cytokines and markers of oxidative stress, microglial activation (IBA-1), and astrocyte activation (GFAP) similar to those seen in the 24-h group. Acute meningitis induction also elevated TSPO, cytochrome c, and caspase-3 levels with no change in caspase-9 levels. Furthermore, upregulated levels of TSPO, cytochrome c, and caspase-3 and caspase-9 were observed in the rat hippocampus 10 days after meningitis induction with a simultaneous reduction in cardiolipin levels. Animals showed a cognitive decline in all tasks compared with the control group, and this impairment may be at least partially mediated by activating a glia-mediated immune response and upregulating TSPO. CONCLUSIONS: TSPO-PET could potentially be used as an imaging biomarker for microglial activation and long-term cognitive impairment post-meningitis. Additionally, this study opens a new avenue for the potential use of TSPO ligands after infection-induced neurological sequelae.