Junchao Gu

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is associated with psychological stress. However, the full landscape of IBS-related epigenetic factors remains unveiled and needs to be elucidated. The water-avoidance stress (WAS) method was used to induce a rat IBS model. Each rat was monitored, and its defecation and behavior were recorded. Total colon RNA was isolated and subjected to Affymetrix GeneChip analysis. Reduced Representation Bisulfate Sequencing (RRBS) was applied to determine the genome-wide methylation pattern in both IBS and control rats. Rats with IBS egested a significantly increased amount of dry and loose stools compared with the control animals, without significant changes in body weight. Compared with the control group, 309 genes were upregulated and 224 genes were downregulated in the colon of the IBS rats. Notch signaling and focal adhesion were increased in the differentially expressed genes (DEGs). A total of 541 genes had significant lower methylation level and 626 genes had significantly higher methylation level in their promoter regions. Adherens junction and leukocyte transendothelial migration were enriched in the differentially methylated genes (DMGs). Few genes were identified in common in both DEGs and DMGs, suggesting that gene expression was not altered by promoter methylation. Reverse transcription-quantitative polymerase chain reaction validation revealed that the mRNA levels of SSX2IP, PARD3 and VCL were significantly downregulated in the IBS group, in accordance with hypermethylation of their promoters. In summary, the present study used a WAS-induced IBS rat model to provide transcriptome and methylome profiling. Most DEGs were associated with Notch signaling and focal adhesion, and only a few were altered by promoter methylation. The present results demonstrated that psychological stress could influence the integrity of the intestinal mucosa barrier and regulate inflammatory response.

Background: Biomarkers for esophageal squamous cell carcinoma (ESCC) identification with high sensitivity are not well established. Since abnormal expression of cadherins has been widely reported in cancer, we explored its feasibility as an ESCC biomarker. Methods: Expression of E-cadherin and N-cadherin were detected in 150 esophageal tissues by immunohistochemistry. Staining strength and percentage in different subcellular structures of each specimen were evaluated by 2 independent pathologists. A logistic regression-based classifier derived from E-cadherin and N-cadherin staining was generated. Results: E-cadherin exhibited decreased membrane expression in ESCC, while N-cadherin exhibited decreased expression in the nucleus but elevated expression in the cytoplasm. Both E-cadherin and N-cadherin could distinguish ESCC tissues from non-cancerous tissues (area under the curve (AUC) = 0.748, 0.801, respectively). E-cadherin and N-cadherin staining scores could be merged into a cadherin (CDH) logistic index, which showed better discrimination (AUC = 0.909) than E-cadherin or N-cadherin alone. Further investigation indicated that the CDH logistic index was significantly correlated with tumor size and differentiation in ESCC. Conclusion: Both E-cadherin and N-cadherin had a strong expression shift in ESCC compared with non-cancerous tissues. The CDH logistic index, a parameter integrating the expression data of both cadherins, could be used as a marker with high sensitivity and specificity in the identification of ESCC.

Neurocysticercosis (NCC) caused by Taeniasolium is one of the most common parasitic diseases of the central nervous system. Inflammation and apoptosis are two main responses involved in NCC pathogenesis. We aimed to examine apoptosis by the TUNEL assay and apoptosis-associated sFas and sFasL levels in the cerebrospinal fluid (CSF) and serum of patients with NCC. Brain biopsy (n = 1), CSF (n = 14), and serum (n = 36) of patients with NCC and uninfected controls (n = 14 and 24 for CSF and serum, respectively) were collected together with clinical data. Residual brain tissue was analyzed by the TUNEL assay. sFas and sFasL in CSF samples and sFas, sFasL, and p53 in serum samples were measured by ELISA. Immunohistochemistry of the biopsy indicated the presence of vimentin-positive arachnoid tissue in the TUNEL-positive region. Compared to controls, sFas was significantly reduced in CSF samples of patients with NCC (P = 0.018), especially among those without inflammation, but significantly increased in the serum samples of the vesicular(P = 0.011), moderate(P = 0.025), and non-epilepsy(P = 0.049) subgroups of patients with NCC. sFasL was elevated in the CSF (P < 0.0001), as well as in the calcified subgroup (P = 0.031), but sFasL levels in CSF were similar among patients with NCC with and without inflammation. These findings support a role of sFas and sFasL in the induction of apoptosis in patients with NCC, with sFas probably being involved in the inflammation phase of NCC and depending on host factors such as parasite stage, disease severity, and symptoms, and sFasL being involved in the inflammation, non-inflammation, and calcification phase of the disease.

Inflammation is the predominant characteristic of pneumonia. The present study aimed to to identify a faster and more reliable novel inflammatory marker for the diagnosis of pneumonia. The expression of the S100A12 gene was analyzed by reverse transcription quantitative polymerase chain reaction in samples obtained from 46 patients with bacterial pneumonia and other infections, compared with samples from 20 healthy individuals, using the 2‑ΔΔCt method. The expression levels of S100A12 were increased in 12 patients with bacterial pneumonia. Compared with clinical inflammatory data, a positive correlation was observed between the expression of the S100A12 gene and levels of white blood cells, C‑reactive protein (CRP), thrombocytocrit, neutrophils, erythrocyte sedimentation and soterocytes, and an inverse correlation was observed with the width of red blood cell volume distribution and platelet distribution, monocytes and hemoglobin, using Pearson's product‑moment correlation method. The P‑value of CRP and erythrocyte sedimentation were revealed to be statistically significant (P1.0) determined using the 2‑ΔΔCt method was associated with more severe respiratory diseases in the patients compromised by bacterial pneumonia, sepsis and pancreatitis. These findings suggested that S100A12 is an effective marker for inflammatory diseases.

To identify the protein from host macrophages which interacted with GRA7 dense granule protein of Toxoplasma gondii, and reveal the relationship between protein interaction and infection process. The recombinant GRA7 protein with N-terminal GST tag were used as a bait in in vitro GST Pull-down experiment, the proteins of THP-1 monocytic macrophage cell line were captured and identified by LC-MS/MS proteomics method. The in vivo protein interaction was verified by Co-IP experiment The overexpression of the target host protein by pcDNA3.1 (+) vector in THP-1 macrophage was further used to analyze the relationship between protein interaction and infection process. The captured THP-1 cell protein was about Mr 29000, which was identified as human carbonic anhydrase 1 (hCA1). The significant in vivo protein-protein interaction between GRA7 and hCA1 was verified by Co-IP assay. The overexpression of hCA1 gene in THP-1 macrophage induced a higher propagation speed of Tgondii and the formation of the parasitophorous vacuole, but did nmt influence the number of the parasite. There is a significant protein interaction between Toxoplasma GRA7 dense granule protein and hCA1 enzyme from host macrophages, which is positively related with the propagation speed of T. gondii.

To separate and identify the surface proteins and secreted proteins of Toxoplasma gondii tachyzoites of RH strain. T. gondii tachyzoites were cultured in Vero cells, and purified by filtration and Percoll cell separation solution. The biotin-labeled tachyzoites were lysed, and the surface and secreted proteins were separated by NeutrAvidin agarose beads. After condensation and SDS-PAGE, the protein were collected, digested and identified by LC/MS-MS. A total of 785 T. gondii proteins were identified, 81 (10.3%) of which were originally annotated as the surface or secreted proteins. Among the highly-expressed (PSM>10) 65 proteins, 43 (66%) were originally annotated as surface or secreted proteins, while the others were predicted unknown proteins. The surface and secreted proteins of T. gondii are separated by biotin labeling and avidin chromatography, among which some potential new surface or secreted proteins of T. gondii are identified.

Telomerase plays an important role in cell proliferation and carcinogenesis and is believed to be a good target for anti-cancer drugs. Elimination of template function of telomerase RNA may repress the telomerase activity.