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The pathogenesis of cognitive impairment in Parkinson's disease (PD) patients remains unclear, and there is no ideal diagnostic tool available at present. We assessed integrated clinical features with plasma and multi-modal neuroimaging biomarkers to identify mild cognitive impairment (MCI) in early drug-naive PD patients. 49 early drug-naive PD patients, including 26 with MCI (PD-MCI) and 23 with normal cognition (PD-NC), and 20 controls were recruited. Plasma markers [α-synuclein, beta-amyloid 1-40 (Aβ40), beta-amyloid 1-42 (Aβ42), and phosphorylated Tau 181 (p-Tau181) levels], functional connectivity (FC) of the default mode network, and cortical thickness (CTh) were evaluated to identify PD-MCI. The PD-MCI group had significantly higher plasma p-Tau181 levels and p-Tau181/Aβ42 ratio and lower Aβ42/Aβ40 ratio compared to the PD-NC group. Compared to PD-NC, the PD-MCI group showed increased FC between left posterior cingulate cortex (pCC) and the left parahippocampal gyrus (PHG), and between the right hippocampal formation and the left anterior cingulate and paracingulate gyri, and the right middle temporal gyrus. Additionally, the PD-MCI group had thinner cortex thickness in the right lateral occipital and frontal pole compared to the PD-NC group. The final model combining clinical characteristics and several variables (age, sex, plasma p-Tau181 level, Aβ42/Aβ40 ratio, the right lateral occipital CTh, and the FC value between the left pCC and left PHG) had the highest diagnostic accuracy for PD-MCI (AUC = 0.987, 95% CI 0.903-1.000

The translocation of transcription factor EB (TFEB) to the nucleus plays a pivotal role in the regulation of basic cellular processes, such as lysosome biogenesis and autophagy. Autophagy is an intracellular degradation system that delivers cytoplasmic constituents to the lysosome, which is important in maintaining cellular homeostasis during environmental stress. Furthermore, oxidative stress is a critical cause for the progression of neurodegenerative diseases. Curcumin has anti-oxidative and anti-inflammatory activities, and is expected to have potential therapeutic effects in various diseases. In this study, we demonstrated that curcumin regulated TFEB export signalling via inhibition of glycogen synthase kinase-3β (GSK-3β); GSK-3β was inactivated by curcumin, leading to reduced phosphorylation of TFEB. We further showed that H2O2-induced oxidative stress was reduced by curcumin via the Nrf2/HO-1 pathway in human neuroblastoma cells. In addition, we showed that curcumin induced the degradation of amyloidogenic proteins, including amyloid-β precursor protein and α-synuclein, through the TFEB-autophagy/lysosomal pathway. In conclusion, curcumin regulates autophagy by controlling TFEB through the inhibition of GSK-3β, and increases antioxidant gene expression in human neuroblastoma cells. These results contribute to the development of novel cellular therapies for neurodegenerative diseases.

Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia, which is a severe and often fatal disease that results in significant economic loss. The means by which A. pleuropneumoniae survives within the host are not clear. High temperature requirement A (HtrA) proteases have been shown to affect cell viability during stressful conditions and are virulence factors in many bacterial species. In this study, we examined the biological role of HtrA during A. pleuropneumoniae infection by analyzing the impact of htrA mutation on virulence-associated phenotypes. We found that htrA mutation had a dramatic impact on stress tolerance. The htrA mutant (ΔhtrA) displayed a lethal phenotype at elevated temperature (42 °C). Further, ΔhtrA exhibited increased susceptibility to H

The qualitative and quantitative determination of marker protein is of great significance in the life sciences and in medicine. Here, we developed an electrochemical DNA biosensor for protein detection based on DNA self-assembly and the terminal protecting effects of small-molecule-linked DNA. This strategy is demonstrated using the small molecule biotin and its receptor protein streptavidin (SA). We immobilized DNA with a designed structure and sequence on the surface of the gold electrode, and we named it M1-Biotin DNA. M1-Biotin DNA selectively combines with SA to generate M1-Biotin-SA DNA and protects M1-Biotin DNA from digestion by EXO III; therefore, M1-Biotin DNA remains intact on the electrode surface. M1-Biotin-SA DNA was modified with methylene blue (MB); the MB reporter molecule is located near the surface of the gold electrode, which generates a substantial electrochemical signal during the detection of SA. Through this strategy, we can exploit the presence or absence of an electrochemical signal to provide qualitative target protein determination as well as the strength of the electrochemical signal to quantitatively analyze the target protein concentration. This strategy has been proven to be used for the quantitative analysis of the interaction between biotin and streptavidin (SA). Under optimal conditions, the detection limit of the proposed biosensor is as low as 18.8 pM, and the linear range is from 0.5 nM to 5 μM, showing high sensitivity. The detection ability of this DNA biosensor in complex serum samples has also been studied. At the same time, we detected the folate receptor (FR) to confirm that this strategy can be used to detect other proteins. Therefore, this electrochemical DNA biosensor provides a sensitive, low-cost, and fast target protein detection platform, which may provide a reliable and powerful tool for early disease diagnosis.

A microRNA (miRNA) detection platform composed of a rolling circle amplification (RCA) system and an allosteric deoxyribozyme system is proposed, which can detect miRNA-21 rapidly and efficiently. Padlock probe hybridization with the target miRNA is achieved through complementary base pairing and the padlock probe forms a closed circular template under the action of ligase, this circular template results in RCA. In the presence of DNA polymerase, RCA proceeds and a long chain with numerous repeating units is formed. In the presence of single-stranded DNA (H1 and H2), multi-component nucleic acid enzymes (MNAzymes) are formed that have the ability to cleave substrates. Finally, substrates containing fluorescent and quenching groups and magnesium ions are added to the system to activate the MNAzyme and the substrate cleavage reaction, thus achieving fluorescence intensity amplification. The RCA–MNAzyme system has dual signal amplification and presents a sensing platform that demonstrates broad prospects in the analysis and detection of nucleic acids.

Faciogenital Dysplasia 1 (FGD1) has been involved in a variety of biological processes, including cytoskeleton restructuring, cell morphology, cell cycle progression, and cell polarity. Abnormal expression of FGD1 was also identified in several types of cancers, indicating its critical role in the development of cancers. However, little is known about the role of FGD1 in hepatocellular carcinoma (HCC). In this study, the expression of FGD1 in HCC was mined with the RNA sequencing data from the cancer genome atlas. By over-expressing or knocking down of FGD1, the effects of FGD1 on the malignant behavior of HCC were evaluated both in vitro and in vivo. We find that FGD1 is up-regulated in HCC and correlated with the development and prognosis of HCC. By over-expressing or knocking down of FGD1, the effects of FGD1 on the malignant behavior of HCC were evaluated both in vitro and in vivo. Knockdown of FGD1 remarkably inhibits the malignant behaviors and causes morphological disorder of pseudopodia, autophagy inhibition and mitochondrial dyfunction in HCC cells. Further investigation shows that Cdc42, a Rho GTPase, plays a role in these processes. Overexpression of FGD1 significantly promotes the oncogenic properties of HCC cells. Collectively, these findings reveal that FGD1 exhibits oncogenic properties in HCC through regulating cell morphology, autophagy and mitochondrial function, suggesting that FGD1 may serve as a potential therapeutic target for HCC.

Oxidative stress is recognised as a key factor that can lead to cellular senescence and aging. Carbon monoxide (CO) is produced by haemoxygenase-1 (HO-1), which exerts cytoprotective effects in aging-related diseases, whereas the effect of CO on cellular senescence and aging has not been elucidated. In the current study, we clearly demonstrated that CO delays the process of cellular senescence and aging through regulation of miR-34a and Sirt1 expression. CO reduced H2O2-induced premature senescence in human diploid fibroblast WI-38 cells measured with SA-β-Gal-staining. Furthermore, CO significantly decreased the expression of senescence-associated secretory phenotype (SASP), including TNF-α IL-6, and PAI-1 and increased the transcriptional levels of antioxidant genes, such as HO-1 and NQO1. Moreover, CO apparently enhanced the expression of Sirt1 through down-regulation of miR-34a. Next, to determine whether Sirt1 mediates the inhibitory effect of CO on cellular senescence, we pre-treated WI-38 cells with the Sirt1 inhibitor Ex527 and a miR-34a mimic followed by the administration of H2O2 and evaluated the expression of SASP and antioxidant genes as well as ROS production. According to our results, Sirt1 is crucial for the antiaging and antioxidant effects of CO. Finally, CO prolonged the lifespan of Caenorhabditis elegans and delayed high-fat diet-induced liver aging. Taken together, these findings demonstrate that CO reduces cellular senescence and liver aging through the regulation of miR-34a and Sirt1.

BACKGROUND: To analyze the main reasons for screening failure in the screening process of healthy subjects in phase I clinical trials and coping strategies. METHODS: We retrospectively collected data from the screening process of 1,640 healthy subjects in 12 phase I clinical trials conducted between April 2019 and July 2020 at the First Affiliated Hospital of Bengbu Medical College. The reasons for screening failure were statistically analyzed (χ(2) test), and correlation studies were conducted to explore the main factors associated with screening failure. RESULTS: Among the 1,640 healthy subjects, 632 (38.5%) successfully passed screening, and 1,008 (61.5%) failed screening. Abnormal laboratory test results (43.25%), abnormal vital sign examination results (11.81%), withdrawal of informed consent (10.02%), abnormal height/weight examination results (8.33%), and abnormal electrocardiogram (ECG) examination results (5.66%) accounted for 79.07% of the screening failures. Subjects aged 46–57 years were more likely to fail screening than those aged 18–30 or 31–45 years (158/220 vs. 541/893 vs. 309/527, respectively, P=0.002), and males were more likely than females to fail screening (721/1, 133 vs. 287/507, respectively, P=0.007). However, the distance between the subject’s residence and clinical trial institution (P=0.491) was not significantly correlated with screening failure. CONCLUSIONS: Before trial screening, healthy subjects should be informed of the clinical trial risks and have sufficient time to consider or discuss participation with their family members. In addition, subjects should be informed that they should eat lightly, have adequate rest, and maintain a relaxed state of mind prior to screening. Regarding fluctuations in the normal range of laboratory indicators and ECG examination reports during the screening process, clinicians should determine the medical decision level (MDL) for each indicator. If no clinical significance is identified, then the subject can be included. In terms of sex and age, this study provides reasonable suggestions to further improve project protocols and improve the healthy subject screening success rate.

TRAF-interacting protein (TRAIP) is a RING-type E3 ubiquitin ligase which has been implicated in various cellular processes, including NF-κB activation, DNA damage response, mitosis, and tumorigenesis. It is considered as a tumor suppressor in basal cell carcinomas and breast cancer in previous studies. However, in our current study, we found that TRAIP exhibited oncogenic properties in liver cancer. In order to determine its effect on tumor biology and the potential mechanism, a variety of advanced experimental technology was used, such as bioinformatic analysis, isobaric tags for relative and absolute quantification (iTRAQ) analysis, tissue microarray detection, and other in vitro cell biology experiments. The results showed that TRAIP was up-regulated in liver cancer and negatively correlated with prognosis. When TRAIP was knocked-down with lentivirus containing specific targeting short hairpin RNAs, the malignant behaviors of Bel7404 cells were significantly inhibited. Meanwhile, overexpression of TRAIP exerted oncogenic effects in SNU449 cells. More importantly, the iTRAQ analysis indicated that TRAIP was significantly related to centriole, centromere, and histone deacetylation, which are critical for mitosis. These findings are in line with previous reports that TRAIP contributes to proper mitosis. Additionally, the iTRAQ analysis also supported that TRAIP may affect G1/S transition by regulating the expression of certain cell cycle related proteins. In summary, our study firstly revealed that TRAIP was up-regulated and negatively correlated with prognosis in liver cancer patients and exhibited oncogenic properties in liver cancer cells, making it a potential target for treatment of liver cancer.

The EarlyCDT®-Lung test was the first autoantibody-based diagnostic tool for lung cancer, which was developed with a panel of recombinant protein antigens. To confirm whether the antibody test developed with linear peptide antigens has a similar power to that developed with the whole protein molecules, the present work was then undertaken to develop an in-house enzyme-linked immunosorbent assay with linear peptide antigens derived from annexin A1 (ANXA1) and DEAD box protein 53 (DDX53), which have been used to develop the EarlyCDT®-Lung test. A total of 272 patients with non-small cell lung cancer (NSCLC) and 227 control subjects matched in age and smoking history were recruited. Student's t test showed that the levels of circulating IgG to ANXA1-derived peptide antigens were significantly higher in patients with NSCLC than control subjects (t = 5.66, P 0.0001), in which the increased anti-ANXA1 IgG levels were observed only in patients at stages I, II, or III, but not in those at stage IV. However, the levels of circulating IgG to DDX53-derived peptide antigens were not significantly altered in NSCLC (t = 1.78, P = 0.076). Receiver operating characteristic analysis showed that the sensitivity against specificity of90% was 23.7% for ANXA1 IgG assay and 13.8% for DDX53 IgG assay. This work suggests that the linear peptide antigen derived from ANXA1 may be suitable for the development of diagnostic tool for lung cancer although further screening is needed to identify more such peptide antigens derived from tumor-associated antigens.

Thymic lymphoma is a highly invasive and even metastatic cancer. This study investigated the effects of mesenchymal stem cells (MSCs) transfusion on cell cycle, cell proliferation, CD3 expression, mutation frequency of T cell receptor using mouse model of thymic lymphoma. C57BL/6J young mouse models of thymoma were injected with MSCs. Six months later, the thymus was taken for pathological examination and flow cytometry studies. The cells were labeled with anti-CD4, CD8, CD3, propidium iodide, or CFDA-SE, cell cycle, proliferation kinetics, and mutation frequency of T cell receptor, respectively. Pathologic results showed that control had clear corticomedular structure with regularly shaped lymphocytes. After radiation, the thymus structure was completely destroyed, with lymphoid tumor cells diffusely distributed and heavily stained, and large nuclei. Transfusion of MSCs resulted in normal thymus structure. Cytometry studies showed that there were more CD4-/CD8- T cells in the thymus of irradiated mice than in control; transfusion of MSCs led to reduced CD4-/CD8- T cells. In irradiated mice, there were less CD4+/CD8+ T cells than in control and MSCs transfusion groups. It was observed that there were more cells arrested in G1 phase in the thymus cells and CD4-/CD8- T cells in irradiated mice than in other 2 groups, whereas there were more cells arrested in S phase in CD4+/CD8+ and CD4+/CD8- T cells in irradiated mice than in the other mice. In the thymus cells, and CD4+/CD8+ and CD4+/CD8- T cells, irradiated mice group had significantly less parent, G2, G3, and G4 cells, and more cells at higher generations, and also higher proliferation index. In CD4-/CD8- T cells, irradiated mice had significantly more parent, G2, and G3 cells, and less G4, G5, G6, and propidium iodide, as compared with the other 2 groups. The expression of CD3 in CD4/CD8 T cells was significantly higher than in control. MSCs transfusion improved CD3 expression, but was still less than the control. Irradiation resulted in very high mutation frequency of T cell receptor, which was barely affected by MSCs transfusion. Mesenchymal stem cell transfusion is able to restore the cell cycle and cell proliferation, but not CD3 expression and mutation frequency of T cell receptor in irradiated mice to control level.