Risk factors of in-hospital mortality in patients with pneumocystis pneumonia diagnosed by metagenomics next-generation sequencing.

Objectives: The metagenomic next-generation sequencing (mNGS) test is useful for rapid and accurate detection and identification of pathogenic microorganisms. The aim of the present study was to investigate the factors associated with in-hospital mortality in pneumocystis pneumonia (PCP) patients with mNGS-assisted diagnosis. Methods: Our study enrolled 154 patients with mNGS-positive PCP from August 2018 to February 2022 at the First Affiliated Hospital of Zhengzhou University respectively. Patients were divided into the survivor group (n=98) and the death group (n=56) according to whether in-hospital death occurred. Baseline characteristics, patients' pre-hospital symptoms and patients' CT imaging performance during hospitalization were carefully compared between the two groups. Risk factors for the occurrence of in-hospital death were sought by selecting indicators that were significantly different between the two groups for modelling and performing multiple logistic regression analysis. Results: Compared with the in-hospital death patients, the survivors were younger and had higher levels of albumin (ALB) (age: 50.29 ± 14.63 years vs 59.39 ± 12.27 years, p<0.001; ALB: 32.24 ± 5.62 g/L vs 29.34 ± 5.42g/L, p=0.002; respectively), while the levels of lactate dehydrogenase (LDH) and C-reactive protein CRP were lower (LDH: 574.67 ± 421.24 U/L vs 960.80 ± 714.94 U/L, p=0.001; CRP: 54.97 ± 55.92 mg/L vs80.45 ± 73.26 mg/L, p=0.018; respectively). Multiple logistic regression analysis revealed that age, the baseline LDH and CRP levels were all positively associated with high in-hospital mortality [age: OR(95%CI): 1.115 (1.062-1.172), p<0.001; LDH: OR(95%CI): 1.002 (1.001-1.003), p<0.001; CRP: OR(95%CI): 1.008 (1.000-1.017), p=0.045; respectively] while the platelet counts was negatively associated with it [OR(95%CI): 0.986 (0.979-0.992), p<0.001]. Conclusions: Old age, high baseline levels of LDH and CRP and low platelet counts were risk factors of the in-hospital mortality in mNGS positive PCP patients.

TGFß1-Smad Signaling Pathway Participates in Interleukin-33 Induced Epithelial-to-Mesenchymal Transition of A549 Cells.

BACKGROUNDS/AIMS: Epithelial-to-mesenchymal transition (EMT) has been proven to be involved in development and progression of pulmonary fibrosis. This study aims to investigate the role of transforming growth factor ß1 (TGFß1)-smad signaling pathway in the interleukin-33 (IL-33) induced EMT. METHODS: The human type II alveolar epithelial cell line, A549, and small airway epithelial cells (SAEC) were cultured and divided into 4 groups including Control, LY-2109761 (TGFß receptor inhibitor), IL-33 and IL-33+LY-2109761 group. Expression of TGFß1, E-cadherin (E-cad) and α-smooth muscle actin (α-SMA) were examined by using real-time PCR (RT-PCR) and western blot assay, respectively. The smad3 signaling pathway factors, including smad3 and phosphorylated smad3 (p-smad3), were also detected by using western blot assay. RESULTS: IL-33 significantly activated T1/ST2 expression in A549 cells (P< 0.05). TGFß1 receptor inhibitor significantly suppressed the IL-33 caused down-expression of E-cad compared to IL-33 alone (P< 0.05). IL-33 significantly increased the α-SMA levels compared to Control group (P< 0.05) and TGFß1 receptor inhibitor inhibited the other effects of IL-33. IL-33 significantly enhanced the levels of TGFß1 compared to Control group (P< 0.05). TGFß1 receptor inhibitor suppressed the IL-33 induced up-expression of p-smad3. CONCLUSION: The TGFß1-smad signaling pathway participates in the IL-33 induced epithelial-to-mesenchymal transition of A549 cells.

Calpain 1 regulates TGF-ß1-induced epithelial-mesenchymal transition in human lung epithelial cells via PI3K/Akt signaling pathway.

Cell proliferation, transformation, and epithelial-mesenchymal transition (EMT) are key processes involved in the development of idiopathic pulmonary fibrosis (IPF). This study investigated the regulatory factors and signaling pathways that mediate EMT in the human type II alveolar epithelial A549 cell line. A549 cells were cultured in RPMI-1640 medium and allocated to the following four groups: blank control group or treated with transforming growth factor-ß1 (TGF-ß1), TGF-ß1 + PD 150606 (a calpain 1 inhibitor), or PD 150606. We examined E-cadherin (E-cad), α-smooth muscle actin (α-SMA), and calpain 1 mRNA transcript and protein expression levels in these four groups by performing RT-PCR and western blot analyses. The results indicated that TGF-ß1 treatment significantly downregulated E-cad and upregulated α-SMA expression compared with that of the blank control group (P<0.05). TGF-ß1 also enhanced calpain 1 expression compared with that of the blank control group (P<0.05). By contrast, treatment with the calpain 1 inhibitor PD 150606 increased E-cad expression and decreased α-SMA expression. Furthermore, PD 150606 treatment antagonized TGF-ß1-mediated increase in Akt/phospho-Akt in A549 epithelial cells. However, TGF-ß1-induced ETM was not correlated with the ERK and JNK signaling pathways. These combined results indicate that calpain 1 could regulate EMT in TGF-ß1-treated A549 epithelial cells via the PI3K/Akt signaling pathway.