Biosensors have become powerful tools for real-time monitoring of specific small molecules and precise control of gene expression in biological systems. High-throughput sensors for 1, 4-butanediamine biosynthesis can greatly improve the screening efficiency of high-yielding 1, 4-butanediamine strains. However, the strategies for adapting the characteristics of biosensors are still rarely studied, which limits the applicability of 1, 4-butanediamine biosensors. In this paper, we propose the development of a 1, 4-butanediamine biosensor based on the transcriptional regulator PuuR, whose homologous operator puuO is installed in the constitutive promoter P_gapA of Escherichia coli to control the expression of the downstream superfolder green fluorescent protein (sfGFP) as the reporter protein. Finally, the biosensor showed a stable linear relationship between the GFP/OD₆₀₀ value and the concentration of 1, 4-butanediamine when the concentration of 1, 4-butanediamine was 0-50 mmol/L. The promoters with different strengths in the E. coli genome were used to modify the 1, 4-butanediamine biosensor, and the functional properties of the PuuR-based 1, 4-butanediamine biosensor were explored and improved, which laid the groundwork for high-throughput screening of engineered strains highly producing 1, 4-butanediamine.
Biosensing Techniques/methods* ; Escherichia coli/metabolism* ; Promoter Regions, Genetic/genetics* ; Green Fluorescent Proteins/metabolism* ; Transcription Factors/genetics* ; Escherichia coli Proteins/genetics* ; Diamines/metabolism* ; Gene Expression Regulation, Bacterial

Colorectal cancer (CRC), a malignant tumor worldwide consists of microsatellite instability (MSI) and stable (MSS) phenotypes. Although SHP2 is a hopeful target for cancer therapy, its relationship with innate immunosuppression remains elusive. To address that, single-cell RNA sequencing was performed to explore the role of SHP2 in all cell types of tumor microenvironment (TME) from murine MC38 xenografts. Intratumoral cells were found to be functionally heterogeneous and responded significantly to SHP099, a SHP2 allosteric inhibitor. The malignant evolution of tumor cells was remarkably arrested by SHP099. Mechanistically, STING-TBK1-IRF3-mediated type I interferon signaling was highly activated by SHP099 in infiltrated myeloid cells. Notably, CRC patients with MSS phenotype exhibited greater macrophage infiltration and more potent SHP2 phosphorylation in CD68⁺ macrophages than MSI-high phenotypes, suggesting the potential role of macrophagic SHP2 in TME. Collectively, our data reveals a mechanism of innate immunosuppression mediated by SHP2, suggesting that SHP2 is a promising target for colon cancer immunotherapy.

Objective    To investigate the effect of artificial colloid on coagulation function in pediatric patients weighing less than 5 kg with congenital heart disease during cardiopulmonary bypass in congenital heart disease surgery by using artificial colloid instead of human serum albumin. Methods    A total of 65 pediatric patients with weight less than 5 kg who underwent congenital heart disease surgery in our hospital from September 2016 to December 2017 were included in the study. They were randomly divided into two groups: an artificial colloid group (the experimental group, n=33) and a human serum albumin combined artificial colloid group (the control group, n=32). Perioperative hemoglobin concentration (Hb), blood products and hemostatic drugs used, postoperative coagulation function index and pleural fluid volume 24 hours after surgery were monitored. Results    There was no significant difference in perioperative Hb and chest tube drainage between the two groups. The platelet utilization rate in the experimental group was significantly lower than that in the control group (P<0.05). No significant difference was found in the dosage of other blood products and hemostatic drugs between the two groups during the perioperative period. There was no significant difference in coagulation parameters between the two groups before and after surgery (P>0.05). Conclusion    The use of artificial colloid as colloid priming solution during cardiopulmonary bypass has no adverse effect on coagulation function in pediatric patients weighting less than 5 kg with congenital heart disease.

Objective To investigate the expression of HSF2 in colonic mucosa of patients with ulcerative colitis (UC),Crohn's disease (CD),intestinal tuberculosis (ITB),intestinal lymphoma (IL),infectious enteritis,Behcet's disease and normal control.Methods Intestinal tissue samples were retrieved from 2003-2011 archived specimen at the Department of Pathology,and assigned to UC group (n =38),CD group (n =29),ITB group (n =31),IL group (n =32),infectious enteritis group (n =32) and Behcet's disease group (n =28).10 cases were recruited as normal control group.The expression of HSF2 in colonic mucosa were detected by immunohistochemistry.Positive cells were counted by Image Analysis.Results The expression rate of HSF2 in intestinal mucosa of UC patients (64.64 ± 15.17) was significantly higher than that of CD (32.44 ± 5.94),ITB (36.93 ± 6.32),IL (36.16 ± 6.55),infectious enteritis (37.86 ±7.76),Behcet's disease (34.90 ±5.92) and normal control (35.54 ±6.76) (P ＜0.05),while there was no significant difference among the latter six groups (P ＞ 0.05).Conclusion HSF2 is closely related with UC,and may play an important role in the pathogenesis,diagnosis and differential diagnosis of UC.