1.Taste signal transduction and the role of taste receptors in the regulation of microbial infection.
West China Journal of Stomatology 2017;35(5):549-554
Taste receptors guide individuals to consume nutrients while avoiding potentially noxious substances. Interestingly, recent studies have shown that taste receptors are also expressed beyond the taste buds, including brain, respiratory system, and digestive system, etc. These extragustatory taste receptors play important roles in microbial infection, nutrient uptake and host homeostasis. Mang extragustatory taste receptors have been proposed to sense microorganisms and regulate host innate defense. More importantly, polymorphisms of genes encoding taste receptor, particularly bitter taste receptor, are linked to different innate defensive responses. This review introduces the molecular basis of taste signal transduction, and the role of taste receptors in the regulation of innate immunity during microbial infection were further discussed in detail.
2.Simulation method of skull remodellingsurgeryfor infant with craniosynostosis.
Shenyu LU ; Yangyu LUO ; Wenjian ZHENG ; Jian GONG
Journal of Biomedical Engineering 2021;38(5):932-939
Craniofacial malformation caused by premature fusion of cranial suture of infants has a serious impact on their growth. The purpose of skull remodeling surgery for infants with craniosynostosis is to expand the skull and allow the brain to grow properly. There are no standardized treatments for skull remodeling surgery at the present, and the postoperative effect can be hardly assessed reasonably. Children with sagittal craniosynostosis were selected as the research objects. By analyzing the morphological characteristics of the patients, the point cloud registration of the skull distortion region with the ideal skull model was performed, and a plan of skull cutting and remodeling surgery was generated. A finite element model of the infant skull was used to predict the growth trend after remodeling surgery. Finally, an experimental study of surgery simulation was carried out with a child with a typical sagittal craniosynostosis. The evaluation results showed that the repositioning and stitching of bone plates effectively improved the morphology of the abnormal parts of the skull and had a normal growth trend. The child's preoperative cephalic index was 65.31%, and became 71.50% after 9 months' growth simulation. The simulation of the skull remodeling provides a reference for surgical plan design. The skull remodeling approach significantly improves postoperative effect, and it could be extended to the generation of cutting and remodeling plans and postoperative evaluations for treatment on other types of craniosynostosis.
Child
;
Computer Simulation
;
Cranial Sutures/surgery*
;
Craniosynostoses/surgery*
;
Humans
;
Infant
;
Skull/surgery*
3.The vicK gene of Streptococcus mutans mediates its cariogenicity via exopolysaccharides metabolism.
Yalan DENG ; Yingming YANG ; Bin ZHANG ; Hong CHEN ; Yangyu LU ; Shirui REN ; Lei LEI ; Tao HU
International Journal of Oral Science 2021;13(1):45-45
Streptococcus mutans (S. mutans) is generally regarded as a major contributor to dental caries because of its ability to synthesize extracellular polysaccharides (EPS) that aid in the formation of plaque biofilm. The VicRKX system of S. mutans plays an important role in biofilm formation. The aim of this study was to investigate the effects of vicK gene on specific characteristics of EPS in S. mutans biofilm. We constructed single-species biofilms formed by different mutants of vicK gene. Production and distribution of EPS were detected through atomic force microscopy, scanning electron microscopy and confocal laser scanning microscopy. Microcosmic structures of EPS were analyzed by gel permeation chromatography and gas chromatography-mass spectrometry. Cariogenicity of the vicK mutant was assessed in a specific pathogen-free rat model. Transcriptional levels of cariogenicity-associated genes were confirmed by quantitative real-time polymerase chain reaction. The results showed that deletion of vicK gene suppressed biofilm formation as well as EPS production, and EPS were synthesized mostly around the cells. Molecular weight and monosaccharide components underwent evident alterations. Biofilms formed in vivo were sparse and contributed a decreased degree of caries. Moreover, expressional levels of genes related to EPS synthesis were down-regulated, except for gtfB. Our report demonstrates that vicK gene enhances biofilm formation and subsequent caries development. And this may due to its regulations on EPS metabolism, like synthesis or microcosmic features of EPS. This study suggests that vicK gene and EPS can be considered as promising targets to modulate dental caries.
Animals
;
Biofilms
;
Dental Caries
;
Dental Plaque
;
Rats
;
Streptococcus mutans/genetics*