This article reports on a noninvasive approach in detecting and following-up individuals who are at-risk or have an existing COVID-19 infection, with a potential ability to serve as an epidemic ...control tool. The proposed method uses a developed breath device composed of a nanomaterial-based hybrid sensor array with multiplexed detection capabilities that can detect disease-specific biomarkers from exhaled breath, thus enabling rapid and accurate diagnosis. An exploratory clinical study with this approach was examined in Wuhan, China, during March 2020. The study cohort included 49 confirmed COVID-19 patients, 58 healthy controls, and 33 non-COVID lung infection controls. When applicable, positive COVID-19 patients were sampled twice: during the active disease and after recovery. Discriminant analysis of the obtained signals from the nanomaterial-based sensors achieved very good test discriminations between the different groups. The training and test set data exhibited respectively 94% and 76% accuracy in differentiating patients from controls as well as 90% and 95% accuracy in differentiating between patients with COVID-19 and patients with other lung infections. While further validation studies are needed, the results may serve as a base for technology that would lead to a reduction in the number of unneeded confirmatory tests and lower the burden on hospitals, while allowing individuals a screening solution that can be performed in PoC facilities. The proposed method can be considered as a platform that could be applied for any other disease infection with proper modifications to the artificial intelligence and would therefore be available to serve as a diagnostic tool in case of a new disease outbreak.
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IJS, KILJ, NUK, PNG, UL, UM
Melatonin, an indolamine produced and secreted predominately by the pineal gland, exhibits a variety of physiological functions, possesses antioxidant and antitumor properties. But, the mechanisms ...for the anti-cancer effects are unknown. The present study explored the effects of melatonin on the migration of human lung adenocarcinoma A549 cells and its mechanism.
MTT assay was employed to measure the viability of A549 cells treated with different concentrations of melatonin. The effect of melatonin on the migration of A549 cells was analyzed by wound healing assay. Occludin location was observed by immunofluorescence. The expression of occludin, osteopontin (OPN), myosin light chain kinase (MLCK) and phosphorylation of myosin light chain (MLC), JNK were detected by western blots.
After A549 cells were treated with melatonin, the viability and migration of the cells were inhibited significantly. The relative migration rate of A549 cells treated with melatonin was only about 20% at 24 h. The expression level of OPN, MLCK and phosphorylation of MLC of A549 cells were reduced, while the expression of occludin was conversely elevated, and occludin located on the cell surface was obviously increased. The phosphorylation status of JNK in A549 cells was also reduced when cells were treated by melatonin.
Melatonin significantly inhibits the migration of A549 cells, and this may be associated with the down-regulation of the expression of OPN, MLCK, phosphorylation of MLC, and up-regulation of the expression of occludin involving JNK/MAPK pathway.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To evaluate the effect of arterial bicarbonate (HCO
) concentration on the accuracy of STOP-Bang questionnaire (SBQ) screening for obstructive sleep apnea (OSA).
A total of 144 patients with ...suspected OSA were included. Polysomnograms (PSG) and blood gas analysis were performed, and the Epworth Sleepiness Scale (ESS), STOP-Bang questionnaire, and Berlin questionnaire were completed. The correlation between the arterial HCO
concentration, apnea hypopnea index (AHI), and other related indicators was analyzed. The scoring results of the ESS, SBQ, and Berlin questionnaire were compared with the PSG results, and the sensitivity and specificity were calculated in the form of a four-cell table. The changes in the sensitivity and specificity of OSA screening after SBQ alone and combined with HCO
concentration were compared, and ROC curves were drawn.
Arterial HCO
concentration was positively correlated with AHI (r = 0.537, P < 0.001). The ratio of HCO
concentration ≥ 24.6 mmol/L in the non-OSA group was significantly lower than that in the OSA group (25.0% VS 80.8%, P < 0.001). The sensitivity of the SBQ was higher than that of the ESS (97.5% VS 81.7%, P < 0.001) and the Berlin questionnaire (97.5% VS 79.2%, P < 0.001). There was no statistical significance in the specificity of the three scales (25%, 37.5%, 37.5%). A combined SBQ score ≥ 3 and HCO
concentration ≥ 24.6 mmol/L showed increased specificity and decreased sensitivity compared with an SBQ score ≥ 3 alone, with a corresponding AUC of 0.771 (P < 0.01) and 0.613 (P > 0.05), respectively.
The sensitivity of the SBQ was better than that of the Berlin questionnaire and ESS. After combining arterial blood HCO
concentration, the SBQ questionnaire increased the specificity of OSA prediction and decreased the sensitivity, which improved the accuracy of screening.
4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative, was reported to function as a tumor inhibitor in various types of cancer cells in vitro. However, ...little is known concerning its antitumor effect on human hepatocellular carcinoma (HCC) HepG2 cells. The aims of the present study were to investigate the effects of ATPR on the proliferation of HepG2 cells and to explore the probable mechanisms. A series of experiments were performed following the treatment of HepG2 cells with ATRA and ATPR. MTT and plate colony formation assays were used to measure the cell viability. To confirm the influence on proliferation, flow cytometry was used to detect the distribution of the cell cycle. Apoptosis was observed by Hoechst staining and flow cytometry. In addition, to characterize the underlying molecular mechanisms, immunofluorescence was applied to observe the distribution of p53. The transcription and translation levels of p53 were analyzed by real-time quantitative RT-PCR (qRT-PCR) and western blotting. The expression levels of murine double minute 2 (MDM2), apoptosis stimulating proteins of p53 (ASPP), cell cycle- and apoptosis-associated proteins were detected by western blotting. After HepG2 cells were incubated with ATRA and ATPR, the viability of the HepG2 cells was inhibited in a dose- and time-dependent manner. As well, ATPR significantly suppressed HepG2 cell colony formation and arrested cells at the G0/G1 phase, while ATRA had no obvious effects. Both Hoechst staining and flow cytometry unveiled the apoptosis of HepG2 cells. Moreover, the fluorescent density of p53 was higher in the nuclei after exposure to ATPR than that in the ATRA group. HepG2 cells treated with ATPR showed elevated mRNA and protein levels of p53 when compared with these levels in the ATRA-treated cells. Western blotting showed that ATPR increased ASPP1, p21 and Bax expression and decreased MDM2, iASPP, cyclin D and E, cyclin-dependent kinase 6 (CDK6) and Bcl-2 expression, while CDK4 and ASPP2 expression were scarcely altered. Consequently, ATPR exerted a better inhibitory effect on the proliferation of HepG2 cells than ATRA through increased expression of p53 and ASPP1 and downregulation of iASPP, thereby resulting in G0/G1 cell cycle arrest and apoptosis.
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•Myosin light chain kinase expression is increased in atherosclerosis.•Phosphorylated myosin light chain increases endothelial dysfunction and permeability.•Myosin light chain kinase ...may reduce NO level via MAP/ERK and MAP/JNK pathways.•Endothelial-dependent relaxation was tested by ultrasound and isolated arterial ring.
Endothelial dysfunction (ED) and hyperpermeability are considered as the initiating steps in early atherosclerosis. Phosphorylation of myosin light chain (MLC) is key to cause vascular hyperpermeability via endothelial cell contraction. However, it is unclear whether MLC phosphorylation can also regulate the balance between contraction and relaxation of endothelial cells, thereby affecting endothelium-dependent diastolic function and leading to ED. The present study investigated relationships between ED and MLC phosphorylation and underlying mechanisms. Twenty-four male New Zealand white rabbits were randomly divided into three groups: control, AS, and ML7 (MLCK inhibitor) groups, and fed with normal diet, high-fat diet (HFD), and HFD plus oral ML7 (1 mg/kg daily) respectively. HFD-fed rabbits showed typical atheromatous lesions and endothelial hyperpermeability, and these lesions could be partly reversed following ML7 therapy. Western blotting revealed significant increased expression of myosin light chain kinase (MLCK) and phosphorylation of MLC, JNK, and ERK in the arterial wall of rabbits in the AS group compared with those of the control group (p < 0.05), whereas the ML7 group showed markedly decreased levels of these proteins compared with the AS group (p < 0.05). The endothelium-dependent relaxation rate was significantly reduced both in vitro and in vivo in AS group, and was improved using ML7 therapy. Taken together, these results indicate that MLCK expression and subsequent MLC phosphorylation increase vascular endothelial permeability and endothelium-dependent diastolic dysfunction by promoting endothelial cell contraction, which may be initiated by the activation of the MAP/ERK (MEK) and MAP/JNK (MEK) pathways.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Paraquat is a commonly used heterocyclic herbicide and has high toxicity by causing acute lung injury. There is no effective treatment for paraquat poisoning. We evaluated the effects of procyanidin ...B2, a natural dietary phytochemical, on paraquat-induced lung injury in rats. Paraquat was used to induce acute lung injury of rats, which were administered with procyanidin B2. The lung injury was evaluated by measuring the lung/body weight ratio, the histology and PMNs count. The oxidative stress was assessed by detecting ROS-mediated indices in the BALF. The expression of IL-1β and IL-18 were detected by RT-PCR and ELISA. The levels of NLRP3 inflammasome components including NLRP3, ASC and caspase-1 were detected by western blot. The lung injury in the paraquat-induced models in NLRP3 gene silenced animals was compared with the same lung injury model treated with procyanidin B2. Administration of procyanidin B2 significantly reduced paraquat-induced lung injury with lower BALF PMNs count, MPO activity, MDA level and elevated SOD activity. Procyanidin B2 suppressed expression of IL-1β and IL-18 at both RNA and protein levels, similar to the NLRP3 gene silenced rats. Compared to paraquat-induced group, procyanidin B2 showed remarkably decreased NLRP3, ASC and caspase-1 signals in the lung tissues in a dose-dependent manner. Procyanidin B2 significantly suppressed the activation of NLRP3 inflammasome in the lung tissue induced by paraquat in the rat model. This finding revealed a novel mechanism by which procyanidin B2 exerts anti-inflammatory effects and their clinical benefits in health.
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GEOZS, IJS, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Krüppel-like factor 4 (KLF4) is an epithelial-specific transcription factor primarily expressed in the gastrointestinal tract that mediates growth arrest in the colonic epithelium. We tried to find ...whether KLF4 expression is associated with the progression and differentiation of colorectal cancer.
We detected KLF4 expression in 109 colorectal specimens (40 normal appearing mucosa, 7 adenomas, and 62 carcinomas) by immunohistochemistry using a tissue microarray. Western blot and RT-PCR analyses were also performed.
The upregulation of KLF4 expression in carcinoma tissue was statistically significant (p<0.05) when compared to normal appearing mucosa. The negative and weak positive staining rates in normal appearing mucosa, adenoma, and carcinoma were 42.5%, 71.4%, and 82.3%, respectively, indicating a decreased degree of KLF4 expression over the course of progressive transformation of normal cells into malignant derivatives. KLF4 protein levels showed no correlation with sex, age, or metastatic state (p>0.05), while KLF4 protein expression correlated with the diagnostic stage (p<0.05). Furthermore, strong KLF4 staining was detected in 22.9% (11/48) and 0% (0/14) of well/moderately and poorly differentiated colorectal cancers, respectively. Our results clearly indicate that KLF4 protein expression significantly correlates with the degree of differentiation in colorectal cancers (p<0.05). KLF4 expression in RKO cells is also upregulated by butyrate, an inducer of differentiation.
Downregulation of KLF4 expression may lead to more poorly differentiated tumors.
Summary
Protein tyrosine‐phosphatases (PTPs) play important roles in various biological processes. Deregulation in PTP function has been implicated in carcinogenesis and tumour progression in many ...cancer types. However, the role of protein tyrosine phosphatase receptor type B (PTPRB) in non‐small‐cell lung cancer (NSCLC) tumorigenesis has not been investigated. Lentiviral vector expressing PTPRB cDNA or shRNA was infected into A549 and H1299 cell lines, followed by cell proliferation, colony formation, soft agar and invasion assays. A549 xenograft mouse model was used to evaluate in vivo function of PTPRB. Quantitative polymerase chain reaction (PCR) was used to measure PTPRB expression in NSCLC patient samples. Kaplan Meier analysis was performed to assess association between PTPRB expression and patient overall survival (OS). Multivariate analysis was performed to evaluate prognostic significance of PTPRB. Overexpression of PTPRB reduced cell proliferation rate, colony formation efficiency, soft agar growth and cell invasion in A549 and H1299 cells, as well as tumour growth rate in A549 xenograft. Knockdown of PTPRB increased Src phosphorylation and cell invasion, which was reversed by Src inhibitor PP2. Additionally, PTPRB was down‐regulated in NSCLC patient and was associated with patient OS. PTPRB regulates Src phosphorylation and tumorigenesis in NSCLC. PTPRB may serve as an independent prognostic biomarker for NSCLC patients.
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DOBA, FSPLJ, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
BACKGROUND Although the oncogenic roles of multiple copies in T-cell malignancy 1 (MCT-1) have been revealed in multiple cancers, its effects on non-small cell lung cancer (NSCLC) progression are ...still uncertain. This study aimed to reveal the effects of MCT-1 on the stem cell-like traits of NSCLC cells. MATERIAL AND METHODS Western blot, real-time quantitative polymerase chain reaction (RT-qPCR), spheroid forming ability, and ALDH1 (aldehyde dehydrogenase 1) activity analysis were carried out to examine the effects of MCT-1/micrRNa-34 (miR-34a)/interleukin-6 (IL-6) on the stem cell-like characteristics of lung cancer cells. RESULTS MCT-1 knockdown reduced the spheroid forming ability, characterized as the decreased spheroid size and number. Additionally, MCT-1 knockdown decreased the expression of the NSCLC stemness markers and the activity of ALDH1. Moreover, MCT-1 knockdown decreased IL-6 secretion that promotes NSCLC cell stemness. Furthermore, MCT-1 knockdown increased the level of miR-34a, which attenuated the stemness of NSCLC cells through targeting IL-6R (IL-6 receptor) expression. CONCLUSIONS These results suggest MCT-1/miR-34a/IL-6/IL-6R axis is responsible for MCT-1-mediated effects on NSCLC cell stemness.
N-(4-hydroxyphenyl)retinamide (4-HPR or fenretinide), which is a synthetic analog of all‑trans retinoic acid (ATRA), effectively inhibits the growth of several types of tumor cells; however, its ...molecular mechanism remains unclear. We found that 4‑HPR altered the morphology of human liver cancer HepG2 cells and also inhibited their proliferation and suppressed the colony formation in a dose‑ and time‑dependent manner. A wound healing assay revealed that 4‑HPR significantly hindered HepG2 cell migration, and that this was accompanied by the phosphorylation of p38‑MAPK (mitogen‑activated protein kinase). Mechanistically, the MAPK‑specific inhibitor SB203580 attenuated the inhibitory effects of 4‑HPR on the migration of HepG2 cells. Moreover, we also observed that 4‑HPR inhibited the activation and expression of myosin light chain kinase (MLCK) in HepG2 cells. Simultaneously, 4‑HPR lowered the expression of F‑actin and promoted the expression of E‑cadherin. ML‑7, a selective inhibitor of MLCK, significantly inhibited the migration of HepG2 cells while increasing the phosphorylation of p38‑MAPK and the expression of E‑cadherin, and decreasing the activation of MLCK and the expression of F‑actin. In conclusion, 4‑HPR inhibited the proliferation and migration of HepG2 cells, and p38‑MAPK plays an important role in regulating these 4‑HPR effects by reducing the activation of MLCK. The present study suggests that 4‑HPR may be a potent antimetastatic agent.