Using esophagus organoid to explore the role of c-Myc in esophageal cancer initiation.

C-Myc gene is aberrantly highly expressed and participates in cancer initiation and development in various malignant tumors including esophageal cancer, while the underlying mechanism(s) still remains unclear. In order to explore the role of c-Myc in the occurrence of esophageal cancer, we successfully established the esophageal organoids (EOs) as the research model. By constructing a lentivirus overexpressing c-Myc and developing more effective infection method, EOs with stable overexpression of c-Myc were efficiently obtained. The morphologies of EOs with or without overexpressing c-Myc were first analyzed with ImageJ, which showed no difference between two groups during continuous subculture. Subsequently, we applied immunofluorescence and CCK8 assays to evaluate the cell proliferation, and the results showed no change in the c-Myc-overexpressed group as compared to control EOs. Furthermore, qPCR was used to detect the expression of genes that are related to cell cycle, cell metabolism as well as esophageal cancer. The results indicated the expression of these genes was not significantly increased in the c-Myc overexpressing EOs. In conclude, we discovered that overexpression of c-Myc gene alone in the esophagus organoid is not sufficient to induce carcinogenesis in esophageal carcinoma. In this study, we successfully established an esophagus organoid culture system and together with efficient lentivirus-infection method for investigation on the effects of overexpressing c-Myc in esophageal cancer. Our work demonstrated a promising research model for the study of esophagus development and esophageal cancer.

Dual Colorimetric and Fluorescent Imaging of Latent Fingerprints on Both Porous and Nonporous Surfaces with Near-Infrared Fluorescent Semiconducting Polymer Dots.

Semiconducting polymer dots (Pdots) have recently been proven as a novel type of ultrabright fluorescent probes that can be extensively used in analytical detection. Here, we developed a dual visual sensor based on Pdots for fingerprint imaging. We first designed and synthesized two types of near-infrared (NIR) fluorescent polymers and then embedded ninhydrin into the Pdot matrix. The resulting Pdot assays showed the colorimetric and fluorescent dual-readout abilities to detect latent fingerprints on both porous and nonporous surfaces. The developed fingerprints clearly revealed first-, second-, and third-level details with high contrast, high selectivity, and low background interference. We also grafted the chemical groups on the nanoparticle surface to investigate the mechanisms involved in the fingerprint development processes. We further utilized this assay in note paper and checks for latent fingerprint imaging. We believe that this dual-readout method based on Pdots will create a new avenue for research in fingerprint detection and anticounterfeiting technology.

Mitotically inactivated embryonic stem cells can be used as an in vivo feeder layer to nurse damaged myocardium after acute myocardial infarction: a preclinical study.

RATIONALE: Various types of viable stem cells have been reported to result in modest improvement in cardiac function after acute myocardial infarction. The mechanisms for improvement from different stem cell populations remain unknown. OBJECTIVE: To determine whether irradiated (nonviable) embryonic stem cells (iESCs) improve postischemic cardiac function without adverse consequences. METHODS AND RESULTS: After coronary artery ligation-induced cardiac infarction, either conditioned media or male murine or male human iESCs were injected into the penumbra of ischemic myocardial tissue of female mice or female rhesus macaque monkeys, respectively. Murine and human iESCs, despite irradiation doses that prevented proliferation and induced cell death, significantly improved cardiac function and decreased infarct size compared with untreated or media-treated controls. Fluorescent in situ hybridization of the Y chromosome revealed disappearance of iESCs within the myocardium, whereas 5-bromo-2'-deoxyuridine assays revealed de novo in vivo cardiomyocyte DNA synthesis. Microarray gene expression profiling demonstrated an early increase in metabolism, DNA proliferation, and chromatin remodeling pathways, and a decrease in fibrosis and inflammatory gene expression compared with media-treated controls. CONCLUSIONS: As a result of irradiation before injection, ex vivo and in vivo iESC existence is transient, yet iESCs provide a significant improvement in cardiac function after acute myocardial infarction. The mechanism(s) of action of iESCs seems to be related to cell-cell exchange, paracrine factors, and a scaffolding effect between iESCs and neighboring host cardiomyocytes.

Role of Blood Neurofilaments in the Prognosis of Amyotrophic Lateral Sclerosis: A Meta-Analysis.

Background: Neurofilaments in cerebrospinal fluid (CSF) and in blood are considered promising biomarkers of amyotrophic lateral sclerosis (ALS) because their levels can be significantly increased in patients with ALS. However, the roles of neurofilaments, especially blood neurofilaments, in the prognosis of ALS are inconsistent. We performed a meta-analysis to explore the prognostic roles of blood neurofilaments in ALS patients. Methods: We searched all relevant studies on the relationship between blood neurofilament levels and the prognosis of ALS patients in PubMed, Embase, Scopus, and Web of Science before February 2, 2021. The quality of the included articles was assessed using the Quality in Prognosis Studies (QUIPS) scale, and R (version 4.02) was used for statistical analysis. Results: Fourteen articles were selected, covering 1,619 ALS patients. The results showed that higher blood neurofilament light chain (NfL) levels in ALS patients were associated with a higher risk of death [medium vs. low NfL level: HR = 2.43, 95% CI (1.34-4.39), p < 0.01; high vs. low NfL level: HR = 4.51, 95% CI (2.45-8.32), p < 0.01]. There was a positive correlation between blood phosphorylated neurofilament heavy chain (pNfH) levels and risk of death in ALS patients [HR = 1.87, 95% CI (1.35-2.59), p < 0.01]. The levels of NfL and pNfH in blood positively correlated with disease progression rate (DPR) of ALS patients [NfL: summary r = 0.53, 95% CI (0.45-0.60), p < 0.01; pNfH: summary r = 0.51, 95% CI (0.24-0.71), p < 0.01]. Conclusion: The blood neurofilament levels can predict the prognosis of ALS patients; specifically, higher levels of blood neurofilaments are associated with a greater risk of death.

Effects of occupational mercury exposure on the immune function of workers / 中国职业医学

@#Objective To investigate the effects of mercury on T lymphocytes and serum immune indexes of workers with Methods occupational mercury exposure. A total of 45 workers with occupational mercury exposure were selected as the ， mercury exposure group and 47 workers without occupational mercury exposure were selected as the control group using the judgment sampling method. Cold atomic absorption spectrometry was used to detect the urinary mercury level of the two groups. （ ） +， + +， + + - + Flow cytometry was used to detect the proportion of cluster of differentiation CD 3 CD3CD4 CD3CD8 and CD3CD19 ， - （ - ） - （ - ） cells in peripheral blood and the levels of tumor necrosis factor α TNF α and interleukin 8 IL 8 in serum. The levels of （ ） ， Results immunoglobulin Ig A IgG and IgM in serum were measured by immune nephelometry. The urinary mercury level of （ ： vs ，P ） individuals in the mercury exposed group was higher than that of the control group median 92.7 13.2 μg/g Cr <0.01 . The +， + +， - + proportion of CD3 CD3CD4 CD3CD19 cells in peripheral blood and serum IgG level in the mercury exposed group （ P ）， - - （ P ） decreased all <0.05 and the serum TNF α and IL 8 levels increased all <0.01 compared with the control group. Urinary - + mercury level was negatively correlated with the proportion of CD3CD19 cells in peripheral blood and serum IgG level in the ［ （r） ， ， P ］， study subjects Spearman correlation coefficient S were −0.21 and −0.31 respectively all <0.05 and positively - - （r ， ， P ） ， correlated with serum TNF α and IL 8 levels S were 0.36 and 0.39 respectively all <0.05 . However the urinary mercury （ P ）， +， + +， level was neither correlated with IgA and IgM levels in serum all >0.05 nor with the proportion of CD3 CD3CD4 + + （ P ） Conclusion CD3CD8 cells in peripheral blood all >0.05 . Occupational exposure to mercury can lead to abnormal ， changes in peripheral blood T lymphocyte subsets B lymphocytes and serum immune factors in workers. The mercury load of occupational mercury exposure workers may impact their immune function.

Tuning the Emission of Semiconducting Polymer Dots from Green to Near-Infrared by Alternating Donor Monomers and Their Applications for in Vivo Biological Imaging.

Semiconducting polymer dots (Pdots) recently have emerged as a new class of extraordinarily bright fluorescent probes with promising applications in biological imaging and sensing. Herein multicolor semiconducting polymer nanoparticles (Pdots) were designed using benzothiadiazole (BT) as the acceptor, and various types of donors were incorporated to modulate their emission wavelengths. Specific cellular targeting and in vivo biotoxicity as well as microangiography imaging on zebrafish indicated these BT-based Pdots are promising candidates for biological applications.