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Paraquat poisoning results in significant pulmonary damage, but current treatments are only minimally effective in repairing the injured lung tissues. Recent research has highlighted the promise of using stem cell therapy, namely mesenchymal stem cells, as a new method for treating paraquat toxicity. These cells have shown effectiveness in decreasing inflammation, apoptosis, and fibrosis in the mice lungs subjected to paraquat. The therapeutic implications of mesenchymal stem cells are believed to arise from their release of bioactive proteins and their capacity to regulate inflammatory responses. However, additional clinical study is required to validate these therapies' efficacy. This review thoroughly explores the pathophysiology of paraquat poisoning and the properties of mesenchymal stem cells. Additionally, it critically assesses the long-term safety and effectiveness of mesenchymal stem cell therapies, which is crucial for developing more dependable and effective treatment protocols. In summary, although mesenchymal stem cells offer promising prospects for treating lung injuries, more investigations are required to optimize their therapeutic promise and ensure their safe clinical application in the context of paraquat poisoning.
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Lesión Pulmonar , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Paraquat , Paraquat/toxicidad , Animales , Humanos , Trasplante de Células Madre Mesenquimatosas/métodos , Lesión Pulmonar/terapia , Lesión Pulmonar/inducido químicamente , Pulmón/patología , RatonesRESUMEN
The aim of this study was to develop a model for early prediction of adverse events and treatment effectiveness in patients with hyperkalemia. We collected clinical data from patients with hyperkalemia in the First Hospital of Zhejiang University School of Medicine between 2015 and 2021. The least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression were used to analyze the predictors on the full dataset. We randomly divided the data into a training group and a validation group, and used LASSO to filter variables in the training set. Six machine learning methods were used to develop the models. The best model was selected based on the area under the curve (AUC). Shapley additive exPlanations (SHAP) values were used to explain the best model. A total of 1074 patients with hyperkalemia were finally enrolled. Diastolic blood pressure (DBP), breathing, oxygen saturation (SPO2), Glasgow coma score (GCS), liver disease, oliguria, blood sodium, international standardized ratio (ISR), and initial blood potassium were the predictors of the occurrence of adverse events; peripheral edema, estimated glomerular filtration rate (eGFR), blood sodium, actual base residual, and initial blood potassium were the predictors of therapeutic effect. Extreme gradient boosting (XGBoost) model achieved the best performance (adverse events: AUC = 0.87; therapeutic effect: AUC = 0.75). A model based on clinical characteristics was developed and validated with good performance.
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Hiperpotasemia , Humanos , Potasio , Área Bajo la Curva , Aprendizaje Automático , SodioRESUMEN
BACKGROUND: The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals. However, no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans. This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning. METHODS: This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022. The entire course of the incidents was described in detail. Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer. Hematoxylin and eosin staining was performed to assess liver injury, and immunofluorescence was used to evaluate hepatic mitophagy. RESULTS: The 2-amino-5-chloro-N,3-dimethylbenzamide powder (99% purity) entered the human body mainly via the skin and respiratory tract due to poor personal protective measures. The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency, rash, fever, organic damage, and recovery phases in accordance with the clinical evolution. Rash and fever may be the important premonitory symptoms for further organ injuries. The chemical was detected in the blood of all patients and caused multiple organ injuries, predominantly liver injury, including kidney, myocardium, and microcirculation. Three patients recovered smoothly after comprehensive treatments, including artificial liver therapy, continuous renal replacement therapy, glucocorticoids, and other symptomatic and supportive treatments. One patient survived by liver transplantation. The postoperative pathological findings of the removed liver showed acute liver failure, and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes. CONCLUSIONS: This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning. The chemical enters the body through the respiratory tract and skin during industrial production. The 2-amino-5-chloro-N,3-dimethylbenzamide poisoning causes multiple-organ dysfunction with a predominance of liver injury. Liver transplantation may be an effective option for patients with severe liver failure. The mechanisms of liver injury induced by 2-amino-5-chloro-N,3-dimethylbenzamide might involve abnormal mitochondrial function and mitophagy.
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Exantema , Fallo Hepático , Trasplante de Hígado , Exposición Profesional , HumanosRESUMEN
OBJECTIVE AND DESIGN: Changes in the immune status of patients with sepsis may have a major impact on their prognosis. Our research focused on changes in various immune cell subsets and T-cell activation during the progression of sepsis. METHODS AND SUBJECTS: We collected data from 188 sepsis patients at the First Affiliated Hospital of Zhejiang University School of Medicine. The main focus was on the patient's immunocyte subset typing, T-cell activation/Treg cell analysis, and cytokine assay, which can indicate the immune status of the patient. RESULTS: The study found that the number of CD4+ T cells, CD8+ T cells, NK cells, and B cells decreased early in the disease, and the decrease in CD4+ and CD8+ T cells was more pronounced in the death group. T lymphocyte activation was inhibited, and the number of Treg cells increased as the disease progressed. T lymphocyte inhibition was more significant in the death group, and the increase in IL-10 was more significant in the death group. Finally, we used patients' baseline conditions and immunological detection indicators for modeling and found that IL-10, CD4+ Treg cells, CD3+HLA-DR+ T cells, and CD3+CD69+ T cells could predict patients' prognosis well. CONCLUSION: Our study found that immunosuppression occurs in patients early in sepsis. Early monitoring of the patient's immune status may provide a timely warning of the disease.
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Citocinas , Sepsis , Humanos , Citocinas/metabolismo , Interleucina-10/metabolismo , Linfocitos T CD8-positivos , Activación de Linfocitos , Linfocitos T Reguladores , Sepsis/metabolismo , Subgrupos de Linfocitos TRESUMEN
A 54-year-old woman in good health was admitted to our hospital with diquat poisoning. The patient drank an unknown dose of diquat, and acute kidney injury developed early. However, there were no obvious pulmonary abnormalities and no signs of central nervous system toxicity in the early stage. The woman underwent active treatment, which resulted in a significant decrease in blood diquat levels, but her lung condition progressively worsened and neurological symptoms developed. Fortunately, the patient survived after intensive hemoperfusion combined with continuous renal replacement therapy (CRRT), intracranial pressure reduction, and anti-infective treatment. This case report highlights the importance of being aware of the development of delayed pulmonary symptoms and neurologic complications when caring for patients poisoned with diquat, even in those with low diquat blood concentrations. Interestingly, we also detected the concentration of diquat in the cerebrospinal fluid (CSF) of patients with diquat poisoning, and found that the rate of decrease of diquat concentration in the CSF was considerably slower than that in the blood.Notably, a specific correlation was observed between the concentration of diquat in the CSF, rather than in the blood, and both the intracranial pressure (ICP) and the severity of cerebral edema in this patient.
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Terapia de Reemplazo Renal Continuo , Hemoperfusión , Intoxicación , Humanos , Femenino , Persona de Mediana Edad , Diquat , Sistema Nervioso Central , Pulmón , Intoxicación/terapiaRESUMEN
The lack of a highly sensitive method to evaluate paraquat (PQ)-induced pulmonary fibrosis and predict disease progression remains an unresolved clinic issue. Fibroblast activation protein (FAP) may play an important role in the pathogenesis of PQ-induced pulmonary fibrosis. We aimed to evaluate the role of FAP in the PQ-induced pulmonary fibrosis and the utility of fibroblast activation protein inhibitor (FAPI) for positron emission tomography (PET) imaging in PQ-induced pulmonary fibrosis. In our study, two cases of PQ poisoning were presented and FAPI PET/CT was performed as a novel imaging technique. The uptake of FAPI increased in both cases of PQ poisoning. Animal experiments were then performed to validate the findings in the patients. Physiological FAPI lung uptake was higher in mice of the PQ group than in the control group. The results of histological analysis and Western blot were consistent with the findings of PET/CT imaging. The pulmonary fibrosis animal model was developed by intragastric gavage of PQ. PET/CT imaging was performed after injection of FAPI. Lung tissues of mice were collected for fibrosis assessment after imaging. Immunohistochemistry for FAP, histology and Western blot for collagen were performed to further validate the imaging findings. In conclusion, FAPI was involved in the pathogenesis of fibrosis induced by PQ, and PET/CT with FAPI could detect lung fibrogenesis, making it a promising tool to assess early disease activity and predict disease progression.
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Fibrosis Pulmonar , Ratones , Humanos , Animales , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/diagnóstico por imagen , Fibrosis Pulmonar/metabolismo , Paraquat , Tomografía Computarizada por Tomografía de Emisión de Positrones , Progresión de la EnfermedadRESUMEN
The CII protein of bacteriophage λ activates transcription from the phage promoters PRE, PI, and PAQ by binding to two direct repeats that straddle the promoter -35 element. Although genetic, biochemical, and structural studies have elucidated many aspects of λCII-mediated transcription activation, no precise structure of the transcription machinery in the process is available. Here, we report a 3.1-Å cryo-electron microscopy (cryo-EM) structure of an intact λCII-dependent transcription activation complex (TAC-λCII), which comprises λCII, E. coli RNAP-σ70 holoenzyme, and the phage promoter PRE. The structure reveals the interactions between λCII and the direct repeats responsible for promoter specificity and the interactions between λCII and RNAP α subunit C-terminal domain responsible for transcription activation. We also determined a 3.4-Å cryo-EM structure of an RNAP-promoter open complex (RPo-PRE) from the same dataset. Structural comparison between TAC-λCII and RPo-PRE provides new insights into λCII-dependent transcription activation.
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Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Activación Transcripcional , Microscopía por Crioelectrón , ARN Polimerasas Dirigidas por ADN/química , Proteínas de Escherichia coli/química , Bacteriófago lambda/genética , Bacteriófago lambda/metabolismo , Transcripción GenéticaRESUMEN
BACKGROUND: Hyperkalemia is common among patients in emergency department and is associated with mortality. While, there is a lack of good evaluation and prediction methods for the efficacy of potassium-lowering treatment, making the drug dosage adjustment quite difficult. We aimed to develop a predictive model to provide early forecasting of treating effects for hyperkalemia patients. METHODS: Around 80% of hyperkalemia patients (n=818) were randomly selected as the training dataset and the remaining 20% (n=196) as the validating dataset. According to the serum potassium (K+) levels after the first round of potassium-lowering treatment, patients were classified into the effective and ineffective groups. Multivariate logistic regression analyses were performed to develop a prediction model. The receiver operating characteristic (ROC) curve and calibration curve analysis were used for model validation. RESULTS: In the training dataset, 429 patients had favorable effects after treatment (effective group), and 389 had poor therapeutic outcomes (ineffective group). Patients in the ineffective group had a higher percentage of renal disease (P=0.007), peripheral edema (P<0.001), oliguria (P=0.001), or higher initial serum K+ level (P<0.001). The percentage of insulin usage was higher in the effective group than in the ineffective group (P=0.005). After multivariate logistic regression analysis, we found age, peripheral edema, oliguria, history of kidney transplantation, end-stage renal disease, insulin, and initial serum K+ were all independently associated with favorable treatment effects. CONCLUSION: The predictive model could provide early forecasting of therapeutic outcomes for hyperkalemia patients after drug treatment, which could help clinicians to identify hyperkalemia patients with high risk and adjust the dosage of medication for potassium-lowering.
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Although the prognostic value of blood creatinine levels in patients with paraquat (PQ) poisoning has been studied for a long time, the results are still controversial. Therefore, we performed the first meta-analysis to comprehensively assess the value of blood creatinine in predicting the prognosis of patients with PQ poisoning. We searched PubMed, EMBase, Web of Science, ScienceDirect, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, and China Online Journals to identify all relevant papers published up to June 2022. Data were extracted for pooled analysis, heterogeneity testing, sensitivity analysis, publication bias analysis, and subgroup analysis. Ultimately, 10 studies involving 862 patients were included. The I2 of diagnostic odds ratio (DOR), sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of this study were all greater than 50%, which showed the existence of heterogeneity in this study, and a random effects model was used for the combination of the above five effect sizes. Pooled analysis showed a high predictive value of blood creatinine for prognosis of PQ poisoning [pooled DOR:22.92, 95% confidence interval (CI):15.62-33.65, P < 0.001]. The combined sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were 86% (95% CI: 0.79-0.91), 78% (95% CI: 0.69-0.86), 4.01 (95% CI: 2.81-5.71), and 0.17 (95% CI: 0.12-0.25), respectively. Deeks publication bias test revealed there was publication bias. Sensitivity analysis showed no significant differences in the estimates of impact. Serum creatinine is an effective predictor of mortality in patients with PQ poisoning.
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Paraquat , Humanos , Creatinina , Pronóstico , ChinaRESUMEN
Paraquat (PQ) poisoning can induce acute lung injury and fibrosis and has an extremely high mortality rate. However, no effective treatments for PQ poisoning have been established. In this study, the potential efficacy of Tripterygium wilfordii Hook.f. (TwHF) in alleviating PQ-induced lung injury and fibrosis was investigated in a mouse model. Mice were randomly assigned to the control, PQ, PQ + TwHF1 (pretreatment before inducing poisoning), and PQ + TwHF2 (treatment after poisoning) groups. The mice in the PQ + TwHF1 group were pretreated with TwHF for 5 days before receiving one dose of PQ (120 mg/kg) and then received a daily oral gavage of the indicated dosages of TwHF until sacrifice. The mice in the PQ + TwHF2 group were treated with TwHF 2 h after PQ exposure until sacrifice. The pathological analysis and Fapi PET/CT showed that treatment with TwHF attenuated lung injury. And TwHF reduced pulmonary oxidative stress, as indicated by the reduction in, malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) levels, as well as by the increase in superoxide dismutase (SOD) levels. Accordingly, the Perls DAB staining showed increased iron concentrations and western blotting revealed a decreased GPX4 expression after PQ exposure, as well as the mitigation of the overexpression of Nrf2 and HO-1 induced by PQ. In conclusion, our study demonstrated the potential of TwHF as a treatment for PQ-induced lung injury and fibrosis. The protective mechanism of this medicinal herb may involve the regulation of ferroptosis.
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Lesión Pulmonar Aguda , Ferroptosis , Animales , Ratones , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Fibrosis , Glutatión/metabolismo , Pulmón , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Paraquat/toxicidad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tripterygium/metabolismoRESUMEN
Numerous researches have evaluated the prevalence and clinical outcome of vitamin D deficiency in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). But the quantitative vitamin D status in acute kidney injury (AKI) patients and its relationship with prognosis remains controversial. We conducted this systemic review and meta-analysis to assess the quantitative difference of vitamin D status, including serum 25(OH) D and 1,25(OH)2D levels, between AKI patients and non-AKI controls, and further explore whether vitamin D status can be clearly correlated with the mortality of AKI. Major databases, including PubMed, Web of Science and EBSCO, were searched until 1st September 2021. All published observational studies related to vitamin D and AKI According to predefined inclusion and exclusion criteria were extracted. Meta-analyses were performed using Review Manager 5.3.5. Four studies including five cohorts were included with a total of 413 patients. The serum 25(OH)D levels showed no statistically significant difference in AKI patients and non-AKI controls. On the other hand, the serum 1,25(OH)2D levels were significant lower in AKI patients than in non-AKI controls (MD = - 17.79, 95% CI = - 32.73 to - 2.85, P = 0.02). As for the relationship between serum vitamin D status and AKI patients' mortality, we were unable to give a consistent conclusion based on current limited and conflict study results. Our meta-analysis suggested that serum 1,25(OH)2D levels, rather than 25(OH)D, is significantly lower in AKI patients. The relationship between vitamin D status and clinical outcome of AKI remains controversial based on current evidence. Future comprehensive studies are required to confirm these relations and to elucidate potential mechanisms.
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Lesión Renal Aguda , Fallo Renal Crónico , Deficiencia de Vitamina D , Humanos , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiología , Vitamina D , VitaminasRESUMEN
BACKGROUND: In the past years, only a few studies with a limited number of adult patients analyzed clinical features of allied disorders of Hirschsprung's disease (ADHD), most of which were individual case reports or lacked detailed clinical information. Although many studies have reported patients presenting to the emergency department (ED) with recurrent abdominal symptoms for a number of disorders, there are few data involving ADHD. However, owing to a lack of awareness of the disease, misdiagnoses and mistreatments are common. Severe complications such as perforation, bleeding, malabsorption, and even death in ADHD had been reported by many studies. AIM: To assist ED clinicians in having a more comprehensive understanding of this disease and making an early suspected diagnosis of ADHD more effectively. METHODS: We enrolled 53 patients who visited the ED and were eventually diagnosed with ADHD over the past 11 years in our hospital. Their basic information, clinical manifestations, and imaging findings were analyzed. Blood indices were compared between the ADHD and irritable bowel syndrome (IBS) groups. RESULTS: Adult patients with ADHD had a mean age of 48.8 ± 14.3 years, and 77.4% had been treated before admission. The transverse colon was the most common dilated part (73.6%), and constipation (67.9%) was the most common symptom. ADHD patients can present with uncommon symptoms and false-negative imaging findings. Logistic regression analysis indicated that body mass index (BMI) [odds ratio (OR) = 0.786, P = 0.013], cholinesterase (per 1000 units; OR = 0.693, P = 0.008), and blood chlorine (OR = 0.816, P = 0.022) were determined to be independent related factors between the ADHD and IBS groups. The area under the receiver operating characteristics curve of these three indices combined was 0.812 (P < 0.001). CONCLUSION: Emergency physicians should be vigilant regarding patients with chronic constipation, abdominal pain, or abdominal distension, and consider the possibility of ADHD despite its rarity. Abdominal computed tomography examination is recommended as a useful tool in the suspected diagnosis of ADHD. BMI, cholinesterase, and blood chlorine have good discriminative abilities between ADHD and IBS. The nutritional status of adult patients with ADHD is worthy of further attention. Surgical treatment for adult patients with ADHD is important and inevitable.
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BACKGROUND: Traumatic aortic dissection (TAD) has a low incidence but extremely high mortality. It always presents atypical clinical manifestations that are easily missed or misdiagnosed. This study mainly aims to describe the imaging characteristics and management of TAD patients. METHODS: A retrospective analysis of 27 blunt TAD patients was performed between 2013 and 2020. Demographic features, imaging characteristics, and management were analyzed. RESULTS: Twenty-seven patients with type B aortic dissection (age 56.04±16.07 years, 20 men) were included. Aortic intimal tears were mostly initiated from the aortic isthmus. The sizes of the proximal intimal tears in the greater curvature were larger than those in the lesser curvature (1.78±0.56 cm vs. 1.24±0.52 cm, P=0.031). Compared with those in the control group, the maximum diameters of the aortic arch, thoracic aorta, and abdominal aorta in the TAD patients were all significantly widened (all P<0.050). Multivariate logistic regression analysis showed that the maximum diameter of the thoracic aorta was an independent risk factor for TAD, with a predictive value with an area under the receiver operating characteristic curve (AUC) of 0.673. Finally, 26 patients successfully underwent delayed thoracic endovascular aortic repair (TEVAR), and the remaining one patient was treated conservatively. No progression of aortic dissection or death occurred during the six-month follow-up period. CONCLUSIONS: In blunt trauma, the aortic isthmus is the most common site of proximal intimal tears. An accurate diagnosis of TAD requires an overall consideration of medical history and imaging characteristics. Delayed TEVAR might be an effective therapeutic option for TAD.
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Síndrome de Sweet , Masculino , Humanos , Síndrome de Sweet/patología , Fiebre/etiología , Neutrófilos/patologíaRESUMEN
Background: The mortality rate of patients with diquat (DQ) poisoning is extremely high due to insufficient understanding of DQ-induced injury. This study aimed to summarize the characteristics of DQ poisoning as well as analyse the correlation between plasma DQ concentration and patient outcomes, thus providing a new strategy for diagnosis and treatment. Methods: This single-centre retrospective cohort study was conducted at the Emergency Department of the First Affiliated Hospital, Zhejiang University School of Medicine, China, between Oct 9, 2019 and March 10, 2022. 50 patients, whose plasma or urine samples tested positive for diquat and negative for paraquat by high performance liquid chromatography-tandem mass spectrometry, were included in the study. Findings: The mortality rate of acute DQ poisoning was 25 (50%) of 50. Compared with the survival group, the death group presented significantly higher initial plasma DQ concentration (Cp1), aspartate aminotransferase, alanine aminotransferase, serum creatinine, and creatine kinase-MB (P < 0.05). We found that six (24.0%) patients died of central nervous system injury, six (24.0%) patients died of refractory circulatory failure, and 13 (52.0%) patients died of central nervous system injury combined with circulatory failure. Receiver operator characteristic curve analysis showed that the area under the curve of Cp1 was 0.967 (95% CI: 0.911, 1.000), and the cut-off value was 3516.885 ng/mL (sensitivity, 90.9%; specificity, 96.0%). Interpretation: Lethal DQ poisoning is primarily associated with serious brain and vascular injury, as well as a high rate of mortality. Further research into the mechanisms of refractory circulatory failure and central nerve system damage could help reduce mortality. Funding: There are no funding sources to declare.
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Progressive immune dysfunction associated with aging is known as immunosenescence. The age-related deterioration of immune function is accompanied by chronic inflammation and microenvironment changes. Immunosenescence can affect both innate and acquired immunity. Sepsis is a systemic inflammatory response that affects parenchymal organs, such as the respiratory system, cardiovascular system, liver, urinary system, and central nervous system, according to the sequential organ failure assessment (SOFA). The initial immune response is characterized by an excess release of inflammatory factors, followed by persistent immune paralysis. Moreover, immunosenescence was found to complement the severity of the immune disorder following sepsis. Furthermore, the immune characteristics associated with sepsis include lymphocytopenia, thymus degeneration, and immunosuppressive cell proliferation, which are very similar to the characteristics of immunosenescence. Therefore, an in-depth understanding of immunosenescence after sepsis and its subsequent effects on the organs may contribute to the development of promising therapeutic strategies. This paper focuses on the characteristics of immunosenescence after sepsis and rigorously analyzes the possible underlying mechanism of action. Based on several recent studies, we summarized the relationship between immunosenescence and sepsis-related organs. We believe that the association between immunosenescence and parenchymal organs might be able to explain the delayed consequences associated with sepsis.
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Enfermedades del Sistema Inmune , Inmunosenescencia , Sepsis , Humanos , Enfermedades del Sistema Inmune/complicaciones , Inflamación/complicacionesRESUMEN
AlpA positively regulates a programmed cell death pathway linked to the virulence of Pseudomonas aeruginosa by recognizing an AlpA binding element within the promoter, then binding RNA polymerase directly and allowing it to bypass an intrinsic terminator positioned downstream. Here, we report the single-particle cryo-electron microscopy structures of both an AlpA-loading complex and an AlpA-loaded complex. These structures indicate that the C-terminal helix-turn-helix motif of AlpA binds to the AlpA binding element and that the N-terminal segment of AlpA forms a narrow ring inside the RNA exit channel. AlpA was also revealed to render RNAP resistant to termination signals by prohibiting RNA hairpin formation in the RNA exit channel. Structural analysis predicted that AlpA, 21Q, λQ and 82Q share the same mechanism of transcription antitermination.