1.Progress on urinary microbiome and urinary tract infection in children
Mengmeng CHEN ; Yi GAN ; Danna TU
International Journal of Pediatrics 2024;51(3):179-182
Urine is not sterile but contains a complex urinary microbiome that is established as early as infancy and gradually refines with age. There are great differences in urinary microbiome of different ages and gender. At present,the core urinary microbiome of children has not reached a consensus. The urinary microbiome plays an important role in maintaining the integrity of urothelium,reducing the overgrowth of pathogenic bacteria,and local immune function. Changes in microbial diversity and composition are associated with various diseases of the urinary system,especially in urinary tract infections. In recent years,research on the relationship between urinary microbiome composition,microbiome,and urinary tract infection in children has been deepening. Therefore,this review aims to provide an overview of the urinary microbiome and its role in urinary tract infection in children,and to summarize the methods of intervening and reshaping the urinary microbiome in children to prevent recurrent urinary tract infections.
2.Analysis and analyzing mechanisms of HERG channel kinetics.
Xianpei WANG ; Lu LI ; Anruo ZOU ; Danna TU ; Yuhua LIAO
Journal of Biomedical Engineering 2008;25(5):1068-1073
We have investigated the methods and mechanisms for analysis of the channel kinetics parameters of voltage-gated potassium channels, HERG (Human ether-à-go-go related gene) channels, in the process of electrophysiological recording. The current of HERG K+ channels expressed in Xenopus oocytes was studied using a two-electrode voltage clamp technique, and the channel kinetics parameters were analyzed through compiling different pulse protocol and recording the current. Results showed: (1) The HERG K+ channels, under conditions of being activated with depolarized pulse, expressed an inward-rectified property attributing to rapid inactivation. The activation curve could be obtained through fitting the depolarized potential and the following peak amplitude of tail current, while the parameters of time-dependent activation was obtained through fitting different depolarized duration and the corresponding peak amplitude of tail current. (2) The I-V relationship still exhibit marked inward rectification. Tail current decay traces were fitted with a bi-exponential function to determine the time constants of the fast and slow components of current decay. (3) The inactivation of HERG channels is voltage-dependent. The inactivation process was isolated with two different three-pulse protocols, with which the inactivation curve and nearly linear I-V relationship were obtained, respectively. Thus, altough the kinetics properties of HERG channels were complicated, the channels kinetics could be indirectly analyzed through differently designed pulse protocols, which provided the basis for investigation on Alanine-scanning mutagenesis and agent action.
Animals
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ERG1 Potassium Channel
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Ether-A-Go-Go Potassium Channels
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analysis
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genetics
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Humans
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Kinetics
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Oocytes
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metabolism
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Patch-Clamp Techniques
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Xenopus laevis
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metabolism