A cross-sectional survey on the lung ultrasound training and practice of respiratory therapists in mainland China.

PURPOSE: This national study aimed to investigate the lung ultrasound (LUS) training and practice of respiratory therapists (RTs) in mainland China. METHODS: A cross-sectional multicenter survey was conducted from May 22, 2021 to August 12, 2021, through online platforms. This survey included RTs in mainland China. The survey was divided into four sections: (1) demographic characteristics and basic information; (2) basic information about LUS training and practice; (3) LUS practice details; and (4) Other ultrasound training and practice. RESULTS: A total of 514 responses were received, and 494 valid responses were included in the analysis. 81.2% (401/494) participants' highest degree of education was a bachelor's degree, and 43.1% (213/494) participants were at level II in terms of job ranking. 99.2%(490/494) participants agreed that the RTs needed to learn lung ultrasound, but only 12.3% (61/494) participants had received a LUS training course. Further, 66.2% (327/494) experienced participants responded to Sect. 3. Most of RTs used LUS when the patient had hypoxia (265/327, 81%) or dyspnea (260/317, 79.5%); they also used it during spontaneous breathing trial(SBT) (191/327, 58.4%) or in prone position (177/327, 54.1%). The A-line (302/327, 92.4%), B-line (299/327, 91.4%), lung slide (263/327, 80.4%), and bat sign (259/327, 79.2%) were well known as LUS signs. Also, 30.6% (100/327) participants did not use the LUS protocol in their clinical practice, and only 25.4%(83/327) participants said they had used LUS scores. Moreover, 55.7% (182/327) participants frequently changed the respiratory therapy strategy according to LUS results. CONCLUSIONS: We should improve the number and workplace of RTs in mainland China in the future. We should also standardize the application of LUS practice and training for RTs in mainland China and establish corresponding certification pathways.

Identifying adsorption sites for Cd(II) and organic dyes on modified straw materials.

Turning agricultural waste into effective remediation materials is a highly promising approach for reducing in-field crop burning and promoting affordable wastewater treatment. This comparative study aims to identify active adsorption sites for methylene blue (MB), crystal violet (CV), and cadmium (Cd) as model pollutants on wheat straw materials modified by a thermal partial-oxidation process. The optimal modification temperature was found to be 160-180 °C for MB and CV adsorption, which is much lower than that of Cd(II) at 220-240 °C. A strong linear correlation exits between total surface group concentrations and Cd(II) uptake, indicating that both acidic and basic functional groups are favourable adsorption sites of Cd(II). By contrast, basic groups generated at higher modification temperatures might have adverse effects on MB and CV adsorption. These results provided mechanistic insights and predictive approach into reuse of agricultural waste for environmental remediation.

Mutual inhibitions between epidermal growth factor receptor signaling and miR-124a control pancreatic progenitor proliferation.

Pancreatic stem/progenitor cells convert from a proliferative to a differentiated fate passing through proliferation cease to a resting state. However, the molecular mechanisms of cell cycle arrest are poorly understood. In this study, we demonstrated that the microRNA-124a (miR-124a) inhibited the proliferation of pancreatic progenitor cells both in vitro and ex vivo and promoted a quiescent state. The miR-124a directly targeted SOS Ras/Rac guanine nucleotide exchange factor 1 (SOS1), IQ motif-containing GTPase-activating protein 1 (IQGAP1), signal transducer and activator of transcription 3 (STAT3), and cyclin D2 (CCND2), thereby inactivating epidermal growth factor receptor (EGFR) downstream signaling pathways including mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK/ERK), phosphatidylinositol 3-kinase-protein kinase B (PI3K/AKT) and Janus kinase (JAK)/STAT3. miR-124a blocked cell proliferation mainly through targeting STAT3 to inhibit PI3K/AKT and JAK/STAT3 signaling. Moreover, miR-124a expression was negatively regulated by EGFR downstream PI3K/AKT signaling. These results indicated that miR-124a and EGFR signaling mutually interact to form a regulating circuit that determines the proliferation of pancreatic progenitor cells.

Notch Signaling in Pancreatic Development.

The Notch signaling pathway plays a significant role in embryonic cell fate determination and adult tissue homeostasis. Various studies have demonstrated the deep involvement of Notch signaling in the development of the pancreas and the lateral inhibition of Notch signaling in pancreatic progenitor differentiation and maintenance. The targeted inactivation of the Notch pathway components promotes premature differentiation of the endocrine pancreas. However, there is still the contrary opinion that Notch signaling specifies the endocrine lineage. Here, we review the current knowledge of the Notch signaling pathway in pancreatic development and its crosstalk with the Wingless and INT-1 (Wnt) and fibroblast growth factor (FGF) pathways.

Small RNA Profiling in Mycobacterium Provides Insights Into Stress Adaptability.

Mycobacteria encounter a number of environmental changes during infection and respond using different mechanisms. Small RNA (sRNA) is a post-transcriptionally regulatory system for gene functions and has been investigated in many other bacteria. This study used Mycobacterium tuberculosis and Mycobacterium bovis Bacillus Calmette-Guérin (BCG) infection models and sequenced whole bacterial RNAs before and after host cell infection. A comparison of differentially expressed sRNAs using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) and target prediction was carried out. Six pathogenically relevant stress conditions, growth rate, and morphology were used to screen and identify sRNAs. From these data, a subset of sRNAs was differentially expressed in multiple infection groups and stress conditions. Many were found associated with lipid metabolism. Among them, ncBCG427 was significantly downregulated when BCG entered into macrophages and was associated with increased biofilm formation. The reduction of virulence possibility depends on regulating lipid metabolism.

Inhibition of the Keap1/Nrf2 Signaling Pathway Significantly Promotes the Progression of Type 1 Diabetes Mellitus.

Type 1 diabetes mellitus (T1DM) is an autoimmune disease characterized by insulin deficiency due to pancreatic ß-cell damage and leads to hyperglycemia. The precise molecular mechanisms of the etiology of T1DM are not completely understood. Oxidative stress and the antioxidant status of pancreatic ß-cells play a vital role in the pathogenesis and progression of T1DM. The Keap1/Nrf2 signaling pathway plays a critical role in cellular resistance to oxidative stress. This study is aimed at investigating the role of the Keap1/Nrf2 signaling pathway in the progression of T1DM. An alloxan- (ALX-) stimulated T1DM animal model in wild-type (WT) and Nrf2 knockout (Nrf2-/-) C57BL/6J mice and a mouse pancreatic ß-cell line (MIN6) were established. Compared with the tolerant (ALX exposure, nondiabetic) WT mice, the sensitive (ALX exposure, diabetic) WT mice exhibited higher blood glucose levels and lower plasma insulin levels. The Keap1/Nrf2 signaling pathway was significantly inhibited in the sensitive WT mice, which was reflected by overexpression of Keap1 and low expression of Nrf2, accompanied by a marked decrease in the expression of the antioxidative enzymes. Compared with WT mice, the Nrf2-/- mice had an increased incidence of T1DM and exhibited more severe pancreatic ß-cell damage. The results of in vitro experiments showed that ALX significantly inhibited the viability and proliferation and promoted the apoptosis of MIN6 cells. ALX also markedly increased intracellular ROS production and caused DNA damage in MIN6 cells. In addition, the Keap1/Nrf2 signaling pathway was significantly inhibited in the damaged MIN6 cells. Moreover, Nrf2 silencing by transfection with Nrf2 siRNA markedly exacerbated ALX-induced MIN6 cell injury. Conclusively, this study demonstrates that inhibition of the Keap1/Nrf2 signaling pathway could significantly promote the incidence of T1DM. This study indicates that activation of Keap1/Nrf2 signaling in pancreatic ß-cells may be a useful pharmacological strategy for the clinical prevention and treatment of T1DM.

Ivermectin Inhibits Bovine Herpesvirus 1 DNA Polymerase Nuclear Import and Interferes with Viral Replication.

Bovine herpesvirus1 (BoHV-1) is a major bovine pathogen. Despite several vaccines being available to prevent viral infection, outbreaks are frequent and cause important economic consequences worldwide. The development of new antiviral drugs is therefore highly desirable. In this context, viral genome replication represents a potential target for therapeutic intervention. BoHV-1 genome is a dsDNA molecule whose replication takes place in the nuclei of infected cells and is mediated by a viral encoded DNA polymerase holoenzyme. Here, we studied the physical interaction and subcellular localization of BoHV-1 DNA polymerase subunits in cells for the first time. By means of co-immunoprecipitation and confocal laser scanning microscopy (CLSM) experiments, we could show that the processivity factor of the DNA polymerase pUL42 is capable of being autonomously transported into the nucleus, whereas the catalytic subunit pUL30 is not. Accordingly, a putative classic NLS (cNLS) was identified on pUL42 but not on pUL30. Importantly, both proteins could interact in the absence of other viral proteins and their co-expression resulted in accumulation of UL30 to the cell nucleus. Treatment of cells with Ivermectin, an anti-parasitic drug which has been recently identified as an inhibitor of importin α/ß-dependent nuclear transport, reduced UL42 nuclear import and specifically reduced BoHV-1 replication in a dose-dependent manner, while virus attachment and entry into cells were not affected. Therefore, this study provides a new option of antiviral therapy for BoHV-1 infection with Ivermectin.

Down-Regulation of miR-378d Increased Rab10 Expression to Help Clearance of Mycobacterium tuberculosis in Macrophages.

Mycobacterium tuberculosis (M. tb) can survive in the hostile microenvironment of cells by escaping host surveillance, but the molecular mechanisms are far from being fully understood. MicroRNAs might be involved in regulation of this intracellular process. By RNAseq of M. tb-infected PMA-differentiated THP-1 macrophages, we previously discovered down-regulation of miR-378d during M. tb infection. This study aimed to investigate the roles of miR-378d in M. tb infection of THP-1 cells by using a miR-378d mimic and inhibitor. First, M. tb infection was confirmed to decrease miR-378d expression in THP-1 and Raw 264.7 macrophages. Then, it was demonstrated that miR-378d mimic promoted, while its inhibitor decreased, M. tb survival in THP-1 cells. Further, the miR-378d mimic suppressed, while its inhibitor enhanced the protein production of IL-1ß, TNF-α, IL-6, and Rab10 expression. By using siRNA of Rab10 (siRab10) to knock-down the Rab10 gene in THP-1 with or without miR-378d inhibitor transfection, Rab10 was determined to be a miR-378d target during M. tb infection. In addition, a dual luciferase reporter assay with the Rab10 wild-type sequence and mutant for miR-378d binding sites confirmed Rab10 as the target of miR-378d associated with M. tb infection. The involvement of four signal pathways NF-κB, P38, JNK, and ERK in miR-378d regulation was determined by detecting the effect of their respective inhibitors on miR-378d expression, and miR-378d inhibitor on activation of these four signal pathways. As a result, activation of the NF-κB signaling pathway was associated with the down-regulation of miR-378d. In conclusion, during M. tb infection of macrophages, miR-378d was down-regulated and functioned on decreasing M. tb intracellular survival by targeting Rab10 and the process was regulated by activation of the NF-κB and induction of pro-inflammatory cytokines IL-1ß, TNF-α, IL-6. These findings shed light on further understanding the defense mechanisms in macrophages against M. tb infection.

Upregulation of Cytokines and Differentiation of Th17 and Treg by Dendritic Cells: Central Role of Prostaglandin E2 Induced by Mycobacterium bovis.

Mycobacterium bovis (M. bovis) is a zoonotic pathogen that causes bovine and human tuberculosis. Dendritic cells play a critical role in initiating and regulating immune responses by promoting antigen-specific T-cell activation. Prostaglandin E2 (PGE2)-COX signaling is an important mediator of inflammation and immunity and might be involved in the pathogenesis of M. bovis infection. Therefore, this study aimed to reveal the character of PGE2 in the differentiation of naïve CD4+ T cells induced by infected dendritic cells (DCs). Murine bone marrow-derived DCs were pre-infected with M. bovis and its attenuated strain M. bovis bacillus Calmette-Guérin (BCG). Then, the infected DCs were co-cultured with naïve CD4+ T cells with or without the cyclooxygenase (COX) inhibitor indomethacin. Quantitative RT-PCR analysis and protein detection showed that PGE2/COX-2 signaling was activated, shown by the upregulation of PGE2 production as well as COX-2 and microsomal PGE2 synthase (mPGES1) transcription in DCs specifically induced by M. bovis and BCG infection. The further co-culture of infected DCs with naïve CD4+ T cells enhanced the generation of inflammatory cytokines IL-17 and IL-23, while indomethacin suppressed their production. Following this, the differentiation of regulatory T cells (Treg) and Th17 cell subsets was significantly induced by the infected DCs rather than uninfected DCs. Meanwhile, M. bovis infection stimulated significantly higher levels of IL-17 and IL-23 and the differentiation of Treg and Th17 cell subsets, while BCG infection led to higher levels of TNF-α and IL-12, but lower proportions of Treg and Th17 cells. In mice, M. bovis infection generated more bacterial load and severe abnormalities in spleens and lungs, as well as higher levels of COX-2, mPGE2 expression, Treg and Th17 cell subsets than BCG infection. In conclusion, PGE2/COX-2 signaling was activated in DCs by M. bovis infection and regulated differentiation of Treg and Th17 cell subsets through the crosstalk between DCs and naive T cells under the cytokine atmosphere of IL-17 and IL-23, which might contribute to M. bovis pathogenesis in mice.

miR-18a counteracts AKT and ERK activation to inhibit the proliferation of pancreatic progenitor cells.

Activation of endogenous stem/progenitor cells to repair injured tissues is an ideal option for disease treatment. However, adult pancreatic progenitor cells remain in a quiescent state in vivo. Thus, it is difficult to stimulate proliferation and differentiation in these progenitor cells, and the cause remains elusive. miR-17-92 cluster miRNAs are highly conserved in mammals and are expressed in multiple tissue stem/progenitor cells, but their role in pancreatic progenitor cells are less well known. In the present study, we demonstrate that miR-18a, but not the other members of the miR-17-92 gene cluster, inhibits the proliferation of pancreatic progenitor cells in vitro and ex vivo. miR-18a inhibits proliferation of adult pancreatic progenitor cells through arresting the cell cycle at G1 stage, indicating that miR-18a plays a role in keeping the adult pancreatic progenitor cells in quiescence. miR-18a inhibits pancreatic progenitor proliferation by targeting the gene expressions of connective tissue growth factor (CTGF), neural precursor cell expressed, developmentally down-regulated 9 (Nedd9), and cyclin dependent kinase 19 (CDK19), as well as by suppressing activation of the proliferation-related signaling pathways phosphatidylinositol 3-kinase-protein kinase B (PI3K/AKT) and extracellular signal-regulated kinase (ERK).

Piperine Plays an Anti-Inflammatory Role in Staphylococcus aureus Endometritis by Inhibiting Activation of NF-κB and MAPK Pathways in Mice.

Endometritis is commonly caused by pathogenic microorganisms, including Staphylococcus aureus (S. aureus). Piperine, which is a natural medicine, has shown a variety of biological activities. To explore the effect and mechanism of piperine on S. aureus endometritis, a mouse model of S. aureus endometritis was successfully established in the present study. Histopathological changes were observed with H&E staining, cytokines were analyzed by ELISA, mRNA was analyzed by qPCR, and proteins were detected by western blot. The results showed that piperine could significantly alleviate inflammatory injury in S. aureus endometritis. The qPCR and ELISA results showed that piperine effectively reduced the S. aureus-induced overexpression of TNF-α, IL-1ß, and IL-6 but increased the expression of IL-10. The S. aureus-induced inflammation was related to TLR-2 and TLR-4 because the results showed that their expression was increased in S. aureus infection but then decreased with piperine treatment. To further confirm that piperine caused an anti-inflammatory response by targeting NF-κB and MAPKs, the expression of I-κB, p65, p38, ERK, and JNK was measured. The phosphorylation of I-κB, p65, p38, ERK, and JNK was inhibited by piperine in a dose-dependent manner. All of the results indicated that piperine may be a potential anti-inflammatory drug both in endometritis and in other S. aureus-induced diseases.

Effect of particle size on solubility, dissolution rate, and oral bioavailability: evaluation using coenzyme Q10 as naked nanocrystals.

In this paper work, four naked nanocrystals (size range 80-700 nm) were prepared without any surfactant or polymer using the solvent/nonsolvent method. The effects of particle size on their solubility, dissolution, and oral bioavailability were investigated. Solubility and dissolution testing were performed in three types of dissolution medium, and the studies demonstrated that the equilibrium solubilities of coenzyme Q10 nanocrystals and bulk drugs were not affected by the dissolution media but the kinetic solubilities were. Kinetic solubility curves and changes in particle size distribution were determined and well explained by the proposed solubilization model for the nanocrystals and bulk drugs. The particle size effect on dissolution was clearly influenced by the diffusion coefficients of the various dissolution media, and the dissolution velocity of coenzyme Q10 increased as particle size decreased. The bioavailability of coenzyme Q10 after oral administration in beagle dogs was improved by reducing the particle size. For 700 nm nanocrystals, the AUC0₋48 was 4.4-fold greater than that for the coarse suspensions, but a further decrease in particle size from 700 nm to 120 nm did not contribute to improvement in bioavailability until the particle size was reduced to 80 nm, when bioavailability was increased by 7.3-fold.