Cytochrome P450 enzymes in the black-spotted frog (Pelophylax nigromaculatus): molecular characterization and upregulation of expression by sulfamethoxazole.

Cytochrome P450 (CYP) enzymes are crucial for the detoxification of xenobiotics, cellular metabolism, and homeostasis. This study investigated the molecular characterization of CYP enzymes in the black-spotted frog, Pelophylax nigromaculatus, and examined the regulation of CYP expression in response to chronic exposure to the antibiotic sulfamethoxazole (SMX) at various environmental concentrations (0, 1, 10, and 100 µg/L). The full-length cDNA of Pn-CYP26B1 was identified. The sequence included open reading frames of 1,536 bp, encoding proteins comprising 511 amino acids. The signature motif, FxxGxxxCxG, was highly conserved when compared with a number of selected animal species. SMX significantly upregulated the expression of the protein CYP26B1 in frog livers at concentrations of 1 and 10 µg/L. SMX showed an affinity for CYP26B1 of -7.6 kcal/mol, indicating a potential mechanism for SMX detoxification or adaptation of the frog. These findings contributed to our understanding of the environmental impact of antibiotics on amphibian species and underscored the importance of CYP enzymes in maintaining biochemical homeostasis under exposure to xenobiotic stress.

Perfluorooctanoic acid and perfluorooctanesulfonic acid induce immunotoxicity through the NF-κB pathway in black-spotted frog (Rana nigromaculata).

Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are widely detected in the environment and wild animals, thus posing a threat to wildlife and public health; however, knowledge about their immunotoxicity and the underlying mechanism remains limited. In the present study, male black-spotted frogs (Rana nigromaculata) were exposed to environmentally relevant concentrations (0, 1, and 10 µg/L) of PFOA or PFOS for 21 days; subsequently, biochemical analysis, molecular docking, and gene expression determination were conducted. The results indicated that exposure to 10 µg/L PFOA decreased the serum levels of immunoglobulin A. PFOS exposure significantly increased the hepatic levels of interleukin-1ß, interleukin-6, tumor necrosis factor-α, interferon-γ, and nitric oxide; but PFOA significantly increased the levels of only tumor necrosis factor-α. Furthermore, PFOA and PFOS exposure significantly decreased the activity of inducible nitric oxide synthase and total nitric oxide synthase. IBRv2 analysis indicated that PFOA and PFOS had a similar effect on these immune indicators, but PFOS was more toxic than PFOA. Molecular docking revealed that PFOA and PFOS can bind to nuclear factor-κB (NF-κB) by forming stable hydrogen bonds. PFOA and PFOS exposure upregulated the gene expression of NF-κB and its downstream genes. Significant correlations between the expression of genes involved in the NF-κB pathway and immune-related indicators suggests that PFOA- and PFOS-induced immunotoxicity was associated with the activation of NF-κB. Our findings provide novel insights into the potential role of NF-κB in immunotoxicity induced by PFOA and PFOS in frogs.

[Risk factors associated with long-term mortality in patients with pulmonary embolism and the predictive value of Charlson comorbidity index].

OBJECTIVE: To explore the risk factors associated with long-term mortality and the predictive value of Charlson comorbidity index (CCI) for long-term mortality in patients with pulmonary embolism (PE). METHODS: A total of 234 patients with confirmed PE from the medical departments of West China Hospital of Sichuan University from January 2010 and December 2012 were enrolled, and these meeting the inclusion criteria were followed-up for 2 years after discharge. The long-term mortality was calculated and univariate and multivariate analysis were performed to identify the risk factors associated with long-term mortality of PE. All the patients were assessed the comorbidity burden with the CCI, and survival analysis was used to study its value in predicting long-term mortality in patients with PE. RESULTS: A total of 176 PE patients were finally included in this study, and 53 patients died during the follow-up period, with 2 years' mortality 30.1%. The univariate analysis showed diabetes (P=0.034), malignant neoplasm (P=0.001), chronic lung disease (P=0.035), liver disease (P=0.048), in bed for a long time (P=0.049), inappropriate anticoagulant therapy (P=0.016) were associated with the long-term mortality of PE patients. Among these risk factors, the multivariate analysis revealed malignant neoplasm (OR=9.28, 95%CI: 2.85-31.00, P=0.003), chronic lung disease (OR=2.96, 95%CI: 1.15-7.62, P=0.024), inappropriate anticoagulant therapy (OR=4.08, 95%CI: 1.64-10.20, P=0.003) were the independent risk factors. The median CCI scores for died PE patients during follow-up was higher than that for the survived PE patients ((2(1, 3) vs 1(0, 2), P<0.001); PE patients with one and more comorbidities (CCI≥1) were associated with 2.61-fold increased risk of long-term mortality compared with patients with no comorbidity (CCI=0) (95%CI: 1.14-6.00, P=0.024). The per 1-score increase of CCI was associated with 1.76-fold increased risk of long-term mortality in PE patients (95%CI: 1.04-2.97, P=0.035). Survival analysis showed that the 2-year cumulative survival of PE patients with CCI score≥1 was significant lower than that of patients with CCI=0 (46.7% vs 78.5%, P=0.003). CONCLUSIONS: Malignant neoplasm, chronic lung disease and inappropriate anticoagulant therapy are independent risk factors of long-term mortality in patients with PE. The CCI can predict long-term mortality risk among patients with PE and the risk increases with the increase of comorbidites patients have.

Efficacy of two noninvasive weaning strategies in intubated patients with chronic obstructive pulmonary disease: A meta-analysis and indirect treatment comparison.

The purpose of our indirect comparison was to explore the optimal switching time to noninvasive ventilation for further weaning in patients with chronic obstructive pulmonary disease (COPD) undergoing invasive mechanical ventilation. A comprehensive literature search was performed to identify randomized controlled trials comparing noninvasive weaning at spontaneous breathing trial (SBT) failure after meeting simple weaning criteria or at the pulmonary infection control window (PIC window) with conventional invasive weaning in COPD patients. Using conventional invasive weaning as a bridge, we indirectly compared the two noninvasive weaning strategies using the Bucher approach. Noninvasive weaning at SBT failure after meeting simple weaning criteria was associated with an extended duration of endotracheal mechanical ventilation (standardized mean difference 1.90, 95% CI 1.27-2.53, P < 0.001) compared with noninvasive weaning at the PIC window. No significant differences in mortality or the rate of ventilator-associated pneumonia were observed. Our study suggests that the PIC window may be a promising switching time for noninvasive weaning in COPD patients.

A Novel Combination of Calprotectin and CXCL12 for Predicting Malignancy in Patients with Exudative Pleural Effusion.

Pleural effusion (PE) remains a significant challenge and public health problem, which needs novel noninvasive biomarkers for the precise diagnosis. The aim of this study was to further determine the clinical efficacy and diagnostic accuracy of a novel combination of calprotectin and CXCL12 for predicting malignancy in patients with exudative PE.Calprotectin and CXCL12 concentrations were measured in 95 individuals of exudative PE, with 39 malignant PE (MPE) and 56 benign PE (BPE). The accuracy of calprotectin and CXCL12 levels for discriminating MPE from BPE or tuberculous PE were evaluated using receiver-operating characteristic (ROC) curves. Univariate and multivariate logistic regression analyses were performed to test the association between calprotectin and CXCL12 levels and MPE.Calprotectin and CXCL12 levels of patients with MPE were significantly lower than that of BPE and tuberculous PE (P < 0.05). The area under the curve (AUC) of calprotectin and CXCL12 was 0.683 and 0.641 in MPE and BPE, and a combination of calprotectin ≤500.19 ng/mL and CXCL12 ≤6.11 ng/mL rendered a sensitivity and specificity of 48.72% and 78.57%, respectively. While in MPE and tuberculous PE, the AUC of calprotectin and CXCL12 was 0.696 and 0.690, and a combination of calprotectin ≤421.73 ng/mL and CXCL12 ≤3.71 ng/mL presented a sensitivity and specificity of 25.64% and 95.45%, respectively. Multivariate logistic regression demonstrated that both calprotectin and CXCL12 were independent predictors of MPE.Calprotectin and CXCL12 in pleural fluid are informative diagnostic biomarkers for predicting patients with MPE.

Initial synchronized intermittent mandatory ventilation versus assist/control ventilation in treatment of moderate acute respiratory distress syndrome: a prospective randomized controlled trial.

BACKGROUND: Assist/control (A/C) ventilation may induce delirium in patients with acute respiratory distress syndrome (ARDS). We conducted a trial to determine whether initial synchronized intermittent mandatory ventilation with pressure support (SIMV + PS) could improve clinical outcomes in these patients. METHODS: Intubated patients with moderate ARDS were enrolled and we compared SIMV + PS with A/C. Identical sedation, analgesia and ventilation strategies were performed. The co-primary outcomes were early (≤72 h) partial pressure of arterial oxygen to fraction of inspired oxygen (PaO2/FiO2) and incidence of delirium. The secondary outcomes were all-cause in-hospital mortality, dosages of analgesics and sedatives, incidence of patient-ventilator asynchrony, and duration of mechanical ventilation and hospital stay. RESULTS: We screened 2,684 patients and 40 patients were enrolled in our study. In SIMV + PS, early (≤72 h) PaO2/FiO2 was greater improved than that at baseline and that in A/C (P<0.05) with lower positive end-expiratory pressure (PEEP) (8.7±3.0 vs. 10.3±3.2, P<0.001) and FiO2 (58%±18% vs. 67%±19%, P<0.001). We found more SIMV + PS success (defined as SIMV + PS successfully applied without switching to A/C) (100.0% vs. 16.7%, P<0.001), less male (46.3% vs. 85.7%, P=0.015) and pulmonary etiology of ARDS (53.8% vs. 92.9%, P=0.015), and lower PEEP (9.1±3.1 vs. 10.3±3.3, P=0.004) and FiO2 (58%±19% vs. 71%±19%, P<0.001) in survival patients. However, there were no significant differences in incidence of delirium and mortality, dosages of analgesics and sedatives, incidence of patient-ventilator asynchrony, duration of mechanical ventilation and hospital stay (P>0.05). CONCLUSIONS: In patients with moderate ARDS, SIMV + PS can safely and effectively improve oxygenation, but does not decrease mortality, incidence of delirium and patient-ventilator asynchrony, dosages of analgesics and sedatives, and duration of mechanical ventilation and hospital stay.