Advances in electrochemically active biofilm of Shewanella oneidensis MR-1 / 生物工程学报

Facing the increasingly severe energy shortage and environmental pollution, electrocatalytic processes using electroactive microorganisms provide a new alternative for achieving environmental-friendly production. Because of its unique respiratory mode and electron transfer ability, Shewanella oneidensis MR-1 has been widely used in the fields of microbial fuel cell, bioelectrosynthesis of value-added chemicals, metal waste treatment and environmental remediation system. The electrochemically active biofilm of S. oneidensis MR-1 is an excellent carrier for transferring the electrons of the electroactive microorganisms. The formation of electrochemically active biofilm is a dynamic and complex process, which is affected by many factors, such as electrode materials, culture conditions, strains and their metabolism. The electrochemically active biofilm plays a very important role in enhancing bacterial environmental stress resistance, improving nutrient uptake and electron transfer efficiency. This paper reviewed the formation process, influencing factors and applications of S. oneidensis MR-1 biofilm in bio-energy, bioremediation and biosensing, with the aim to facilitate and expand its further application.

Paroxysmal Dyskinesia in Children: from Genes to the Clinic

BACKGROUND AND PURPOSE: Paroxysmal dyskinesia is a genetically and clinically heterogeneous movement disorder. Recent studies have shown that it exhibits both phenotype and genotype overlap with other paroxysmal disorders as well as clinical heterogeneity. We investigated the clinical and genetic characteristics of paroxysmal dyskinesia in children. METHODS: Fifty-five patients (16 from 14 families and 39 sporadic cases) were enrolled. We classified them into three phenotypes: paroxysmal kinesigenic dyskinesia (PKD), paroxysmal nonkinesigenic dyskinesia (PNKD), and paroxysmal exercise-induced dyskinesia (PED). We sequenced PRRT2, SLC2A1, and MR-1 in these patients and reviewed their medical records. RESULTS: Forty patients were categorized as PKD, 14 as PNKD, and 1 as PED. Thirty-eight (69.1%) patients were male, and their age at onset was 8.80±4.53 years (mean±SD). Dystonia was the most common symptom (38 patients, 69.1%). Pathogenic variants were identified in 20 patients (36.4%): 18 with PRRT2 and 2 with SLC2A1. All of the patients with PRRT2 mutations presented with PKD alone. The 2 patients carrying SLC2A1 mutations presented as PNKD and PED, and one of them was treated effectively with a ketogenic diet. Six mutations in PRRT2 (including 2 novel variants) were identified in 9 of the 13 tested families (69.2%) and in 8 patients of the 25 tested sporadic cases (32.0%). There were no significant differences in clinical features or drug response between the PRRT2-positive and PRRT2-negative PKD groups. CONCLUSIONS: This study has summarized the clinical and genetic heterogeneity of paroxysmal dyskinesia in children. We suggest that pediatric paroxysmal dyskinesia should not be diagnosed using clinical features alone, but by combining them with broader genetic testing.

Mucosal-associated Invariant T cells: A New Player in Innate Immunity

Mucosal-associated invariant T (MAIT) cells are evolutionarily conserved T cells that are restricted by the non-classical major histocompatibility complex class-1b molecule MR1. MAIT cells recognize riboflavin (vitamin B2) derivatives in a MR1-dependent manner. Following antigen recongnition, MAIT cells rapidly produce Th1/Th17 cytokines, such as interferon-gamma and interleukin-17, in an innate-like manner. MAIT cells maintain an activated phenotype throughout the course of an infection, secrete inflammatory cytokines, and have the potential to directly kill infected cells, thus, playing an important role in controlling the host response. In this review, we discuss current knowledge regarding the role of MAIT cells in infectious diseases, cancers, and autoimmune diseases.

MR1 siRNA suppresses proliferation of human hepatoma BEL-7402 cells / 基础医学与临床

Objective To identify the function and mechanism of MR1 in proliferation of BEL-7402 cells.Methods siRNA targeting MR1 and negative control siRNA were synthesized and transfected into BEL-7402 cells using Lipofectamine 2000.The silencing effect of MR1 siRNA was determined by semi-RT-PCR.SRB assay,colony formation assay and growth curve assay were used to investigate whether MR1 siRNA regulated cellular proliferation.Cell cycles were assessed by flow cytometry.G2 arrest reagent nocodazole was used to show the potential effect of MR1 siRNA on G1 arrest.The expression of Cyclin D1 was determined by Western blotting.Results(1)MR1 mRNA significantly decreased in BEL-7402 cells 24 h after MR1 siRNA transfection.(2)MR1 siRNA induced the down-regulation of cell growth.The expression of Cyclin D1 in MR1 siRNA tranfected BEL-7402 cells decreased significantly.(3)Flow cytometry results showed that MR1 siRNA markedly decreased G2 phase population with nocodazole treatment,and distinctly increased G1 phase population.Conclusion The gene MR1 is involved in the proliferation of BEL-7402 cells.MR1 siRNA causes inhibition of the proliferation of BEL-7402 cells.One of the mechanisms ofMR1 siRNA on the proliferation of BEL-7402 cells is the induction of G1 arrest.