Bifidobacterium pseudocatenulatum NCU-08 ameliorated senescence via modulation of the AMPK/Sirt1 signaling pathway and gut microbiota in mice.

Aging is a degenerative disease in which organisms and neurological functions decline. Emerging research has underscored the vital role of the gut microbiota in age-related processes. However, the identification of aging-associated core microbiota remains limited. In this investigation, we isolated a strain of B. pseudocatenulatum NCU-08 from the feces of centenarians and assessed its impact on aging using a mouse model induced by D-gal. Our study revealed the exceptional probiotic attributes of B. pseudocatenulatum NCU-08. Administration of B. pseudocatenulatum NCU-08 significantly ameliorated age-related memory impairment, motor dysfunction, and anxiety-like behaviors in aging mice (p < 0.01). Moreover, tissue staining analysis demonstrated that B. pseudocatenulatum NCU-08 reduced the intensity of SA-ß-gal-positive in the hippocampus of aging mice. It also reversed pathological damage and structural abnormalities in brain and intestinal tissue. B. pseudocatenulatum NCU-08 inhibited neuroinflammation induced by TLR4/NF-κB (p < 0.01) and preserved the blood-brain barrier integrity by activating the AMPK/Sirt1 pathway (p < 0.05). Furthermore, it mitigated neuronal apoptosis and oxidative stress by upregulating the PI3K/AKT signaling pathway (p < 0.01) and enhancing the activities of antioxidant enzymes, including GSH-Px (p < 0.01), SOD (p < 0.01), and CAT (p < 0.01). Besides, analysis of 16S rRNA sequencing data demonstrated that treatment with B. pseudocatenulatum NCU-08 restored intestinal microbiota homeostasis after senescence. It enhanced the abundance of beneficial bacteria while suppressing the growth of pathogenic microorganisms. In summary, our study unveiled that this novel strain of B. pseudocatenulatum NCU-08 exerts anti-aging effects through regulating the AMPK/Sirt1 pathway and intestinal microbiota. It holds promise as a functional food for promoting anti-aging effects and offers a novel approach to address aging and associated metabolic disorders.

Rapid identification of pathogens associated with ventilator-associated pneumonia by Nanopore sequencing.

BACKGROUND: Aetiology detection is crucial in the diagnosis and treatment of ventilator-associated pneumonia (VAP). However, the detection method needs improvement. In this study, we used Nanopore sequencing to build a quick detection protocol and compared the efficiency of different methods for detecting 7 VAP pathogens. METHODS: The endotracheal aspirate (ETA) of 83 patients with suspected VAP from Peking University Third Hospital (PUTH) was collected, saponins were used to deplete host genomes, and PCR- or non-PCR-amplified library construction methods were used and compared. Sequence was performed with MinION equipment and local data analysis methods were used for sequencing and data analysis. RESULTS: Saponin depletion effectively removed 11 of 12 human genomes, while most pathogenic bacterial genome results showed no significant difference except for S. pneumoniae. Moreover, the average sequence time decreased from 19.6 h to 3.62 h. The non-PCR amplification method and PCR amplification method for library build has a similar average sensitivity (85.8% vs. 86.35%), but the non-PCR amplification method has a better average specificity (100% VS 91.15%), and required less time. The whole method takes 5-6 h from ETA extraction to pathogen classification. After analysing the 7 pathogens enrolled in our study, the average sensitivity of metagenomic sequencing was approximately 2.4 times higher than that of clinical culture (89.15% vs. 37.77%), and the average specificity was 98.8%. CONCLUSIONS: Using saponins to remove the human genome and a non-PCR amplification method to build libraries can be used for the identification of pathogens in the ETA of VAP patients within 6 h by MinION, which provides a new approach for the rapid identification of pathogens in clinical departments.

Performance and comparison of assessment models to predict 30-day mortality in patients with hospital-acquired pneumonia.

BACKGROUND: Hospital-acquired pneumonia (HAP) is the most common hospital-acquired infection in China with substantial morbidity and mortality. But no specific risk assessment model has been well validated in patients with HAP. The aim of this study was to investigate the published risk assessment models that could potentially be used to predict 30-day mortality in HAP patients in non-surgical departments. METHODS: This study was a single-center, retrospective study. In total, 223 patients diagnosed with HAP from 2012 to 2017 were included in this study. Clinical and laboratory data during the initial 24 hours after HAP diagnosis were collected to calculate the pneumonia severity index (PSI); consciousness, urea nitrogen, respiratory rate, blood pressure, and age ≥65 years (CURB-65); Acute Physiology and Chronic Health Evaluation II (APACHE II); Sequential Organ Failure Assessment (SOFA); and Quick Sequential Organ Failure Assessment (qSOFA) scores. The discriminatory power was tested by constructing receiver operating characteristic (ROC) curves, and the areas under the curve (AUCs) were calculated. RESULTS: The all-cause 30-day mortality rate was 18.4% (41/223). The PSI, CURB-65, SOFA, APACHE II, and qSOFA scores were significantly higher in non-survivors than in survivors (all P < 0.001). The discriminatory abilities of the APACHE II and SOFA scores were better than those of the CURB-65 and qSOFA scores (ROC AUC: APACHE II vs. CURB-65, 0.863 vs. 0.744, Z = 3.055, P = 0.002; APACHE II vs. qSOFA, 0.863 vs. 0.767, Z = 3.017, P = 0.003; SOFA vs. CURB-65, 0.856 vs. 0.744, Z = 2.589, P = 0.010; SOFA vs. qSOFA, 0.856 vs. 0.767, Z = 2.170, P = 0.030). The cut-off values we defined for the SOFA, APACHE II, and qSOFA scores were 4, 14, and 1. CONCLUSIONS: These results suggest that the APACHE II and SOFA scores determined during the initial 24 h after HAP diagnosis may be useful for the prediction of 30-day mortality in HAP patients in non-surgical departments. The qSOFA score may be a simple tool that can be used to quickly identify severe infections.

The diagnostic role of a short screening tool--the distress thermometer: a meta-analysis.

PURPOSE: The Distress Thermometer (the DT) is a commonly used screening tool to detect distress in cancer patients. This meta-analysis aims to examine the diagnostic role and the optimal cut-off score of the DT compared with various different reference standards. METHODS: We searched PubMed and Embase from 1997 to September 2013 for relevant studies. After extracting data, we estimated the pooled sensitivity, specificity, likelihood ratios, diagnostic odds ratios, and constructed summary receiver operating characteristics curves to determine the optimal cut-off score. RESULTS: Forty-two relevant studies and 14,808 patients were included in total. When we pooled all the results together, the DT showed a good balance between pooled sensitivity (0.81, 95% confidence intervals (CI) 0.79-0.82) and pooled specificity (0.72, 95% CI 0.71-0.72) at the cut-off score of 4. The value of area under the curve (AUC) is 0.8321. When the DT is compared with the HADS-Total, the cut-off score of 4 maximized the balance between the pooled sensitivity (0.82, 95% CI 0.80-0.84) and pooled specificity (0.73, 95% CI 0.72-0.74). The AUC is 0.8432. CONCLUSIONS: This meta-analysis suggests that the DT is a valid tool to detect potential distress in cancer patients. According to our results, 4 as the optimal cut-off, is recommended. Further studies are needed to be done to examine the accuracy and optimal cut-off score in different regions globally and different cancer subtypes to guide the use of the DT for different patients.

Emerging role of microRNAs in cancer and cancer stem cells.

Cancer stem cells (CSCs), or cancer cells with stem cell properties, represent a small fraction of tumor bulk and are thought to be responsible for tumor formation and metastasis. However, the mechanisms of how CSCs are generated and regulated at the molecular level are poorly understood. Recent progress has highlighted the significance of microRNAs (miRNAs) in cancer progression and CSC function. The function and dysfunction of miRNAs in the development of cancer and CSCs have become a burgeoning area of intense research. A new finding has elucidated a mechanism of antagonistic miRNA crosstalk whereby one miRNA can inhibit another miRNA in regulating CSCs. Herein we make this short review to summarize the current understanding of the regulatory mechanisms of miRNAs in cancer and CSCs and discuss the implications of targeting CSCs for cancer therapeutics.