0.05). The titrimetric determination of standard solution containing different levels of chloride showed recovery rates of 98.0%～103.7%, relative standard deviation was 0.16%. Conclusion Automatic potentiometric titration was easy to grasp, rapid and accurate, which was a new analytical method worthy to be applied extensively.

Objective:To observe the development process of the neuronal synapse in cerebral cortex and basal ganglionic eminence(GE)regions of the mice,and to clarify the differences in the development of excitatory and inhibitory synapses in different brain regions in vivo and in vitro.Methods:The female C57BL/6 mice were euthanized by cervical dislocation from the 13.5th day to the 15.5th day during the pregnancy,and the embryos were collected under the sterile conditions.The cortex and GE regions of brain tissue of the embryonic mice were gradually isolated under microscope.The primary neurons from the embryonic mice were cultured in vitro,and the cell samples were collected on the 3rd,7th,14th,and 21th days,respectively,and regarded as culture 3 d,7 d,14 d,and 21 d groups.The expression levels of postsynaptic density 95(PSD95)and Gephyrin mRNA in the primary neurons from the cortex and GE regions of the mice in various groups were detected by real-time fluorescence quantitative PCR(RT-qPCR)method.Immunofluorescence method was used to detect the expression levels of vesicular glutamate transporter 1(vGLUT1),PSD95,vesicular GABA transporter(vGAT),and Gephyrin proteins in the neurons from the cortex and GE regions of the mice in various groups.Immunofluorescence method was also used to detect the expression levels of vGLUT1 and vGAT proteins in the neurons from the cortical and GE regions in brain tissue of the embryonic mice.Results:Compared with culture 3 d group,the expression levels of PSD95 and Gephyrin mRNA in cortex and GE regions of the mice in culture 14 d and 21 d groups were significantly increased(P<0.01).Compared with cortex area,the expression level of Gephyrin mRNA in the neurons from GE region of the mice in culture 14 d group was significantly decreased(P<0.01).The microscope observation results showed that the excitatory and inhibitory synapses in the neurons from cortex and GE regions of the mice in culture 14 d group showed preliminary development,with positive expression of relevant proteins;among them,the excitatory synaptic proteins showed more distinct positive expression in the cortex neurons,and the presynaptic vGLUT1 and postsynaptic PSD95 molecules exhibited co-localization in the cell bodies and protrusions of the cortical neurons;the inhibitory presynaptic vGAT protein and postsynaptic Gephyrin protein in the neurons from GE region also exhibited co-localization in the cell bodies and protrusions,and there were more distinct expressions of the presynaptic molecule proteins than postsynaptic molecule proteins.Compared with cortex region,the levels of vGLUT1 and PSD95 proteins in the neurons from GE region of the mice in culture 14 d group were significantly decreased(P<0.01),while the levels of vGAT and gephyrin proteins were significantly increased(P<0.01).In culture 21 d group,the positive expressions of synaptic protein in the neurons from cortex and GE regions were increased,and the excitatory and inhibitory synapses further matured and enhanced.In the neurons from cortex and GE regions,rich patterns of corresponding pre-and postsynaptic expression were formed in the cell bodies and protrusions,and synapse structures showed gradual,positive development,with more apparent expression of presynaptic molecules compared wih postsynaptic proteins.Compared with cortex region,the levels of vGLUT1 and PSD95 proteins in the neurons from GE region of the mice in culture 21 d group were significantly decreased(P<0.01),and the levels of vGAT and Gephyrin proteins were significantly increased(P<0.01).Compared with cortex region,the expression level of vGLUT1 protein in the neurons from GE region in brain tissue of the embryonic mice was significantly decreased(P<0.01),while the expression level of vGAT protein was significantly increased(P<0.05).Conclusion:There are distinct differences in synaptic development between the neurons from cortex and GE regions,the excitatory synapses develope earlier in the cortical region and the inhibitory synapses develope earlier in the GE region.The region-specific development of synapses suggests that different types of neural diseases with different cell types might originate from different developmental processes.

Objective:To investigate the correlation between Piwi-interacting RNA (piRNA) and diabetic nephropathy (DN).Methods:The differential expression profiles of piRNAs in renal tissues of patients with DN (experimental group) and renal tissues adjacent to tumors of patients with renal tumors (control group) were detected by high-throughput sequencing. The biological function of differentially expressed piRNAs was described by gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis. Real-time fluorescence quantitative PCR was used to detect the serum expression level of target piRNAs in patients with DN. Spearman correlation analysis was used to analyze the correlation between serum target piRNAs and clinical indexes of patients with DN.Results:The results of high throughput sequencing showed that there were 127 differentially expressed piRNAs between DN group and control group, with screening condition of |log 2(fold changes)|≥2 and P<0.05. Among them, there were 99 up-regulated piRNAs and 28 down-regulated piRNAs. The top 5 up-regulated piRNAs were piRNA-hsa-161686, piRNA-hsa-349255, piRNA-hsa-355720, piRNA-hsa-151229 and piRNA-hsa-154959, respectively. The top 5 down-regulated piRNAs were piRNA-hsa-1929960, piRNA-hsa-174194, piRNA-hsa- 148658, piRNA-hsa-172594 and piRNA-hsa-172421, respectively. The PCR verification results of 3 up-regulated genes and 3 down-regulated genes with low P values and high expression levels showed that serum expression level of piRNA-hsa-77976 was significantly down-regulated in patients with DN ( P=0.028), which was consistent with that of sequencing, while the expression levels of other genes were inconsistent with the sequencing results or had no statistical significance. Bioinformatics analysis results predicted that significantly differentially expressed piRNAs might participate in the regulation of DN through Rap1, Ras, PI3K-Akt and axon guiding pathways. The results of correlation analysis showed that the expression level of piRNA-hsa-77976 was negatively correlated with blood urea nitrogen ( r=-0.584, P=0.028), serum creatinine ( r=-0.637, P=0.014), cystatin C ( r=-0.738, P=0.003) and β2 microglobulin ( r=-0.822, P<0.001), and positively correlated with estimated glomerular filtration rate ( r=0.661, P=0.010). Conclusion:The differential expression of piRNA is closely related to DN, and may be used as a new biomarker for the diagnosis and prognosis of DN.

Objective To observe the changes of plasma gastrointestinal hormones in motion sickness sensitive and insensitive individuals before and after vertical oscillation stimulation,and to construct a susceptibility prediction model for motion sickness.Methods A total of 60 healthy male volunteers were enrolled to receive sinusoidal vertical oscillation stimulation for 45 min.The motion sickness susceptibility questionnaire(MSSQ)was filled out before the experiment.Immediately after motion,the severity of motion sickness was evaluated by Graybiel scale.The motion sickness sensitive(Graybiel score≥8 and MSSQ susceptibility index＞21,n=15)and insensitive(Graybiel score≤2 and MSSQ susceptibility index＜5,n=15)participants were screened.Plasma levels of glucagon-like peptide-1(GLP-1),cholecystokinin(CCK),leptin,ghrelin,neuropeptide Y(NPY)and orexin A(OXA)were detected by enzyme-linked immunosorbent assay before and after vertical oscillation stimulation.Logistic regression model was used to analyze the predictive effect of plasma gastrointestinal hormone levels on susceptibility to motion sickness,and a combined predictive model was established.Receiver operating characteristic(ROC)curve was used to analyze predictive value of the model.Results Ghrelin and CCK levels were significantly increased in the sensitive group after stimulation compared with those before stimulation(both P＜0.01),while NPY and leptin levels were significantly decreased(both P＜0.01).Similar results were also observed when compared with the insensitive group after stimulation.Multivariate logistic regression analysis showed that plasma ghrelin,CCK and NPY were independent predictors of susceptibility to motion sickness.The established susceptibility prediction model for motion sickness was logit(P)=-0.051 ×ghrelin+0.060× NPY-0.169 ×CCK+33.397.ROC curve analysis showed that area under curve(AUC)value of the prediction model was 0.988,the sensitivity and specificity were 100.0％and 93.3％,respectively,and the prediction effect was better than ghrelin,CCK and NPY alone(AUC=0.792,0.880,0.838).Conclusion The changes of peripheral gastrointestinal appetite regulating hormone levels may be related to the susceptibility to motion sickness.The combined use of these indicators can predict the susceptibility to motion sickness.

OBJECTIVE: To investigate the role of the SIRT1/NF-κB pathway in mediating the effect of puerarin against lipopolysaccharide (LPS)-induced acute kidney injury (AKI). METHODS: Fifteen BALB/C mice were randomized into control group, LPS group and puerarin treatment group, and in the latter two groups, the mice were given an intraperitoneal injection of LPS (5 mg/kg), followed by daily injection of normal saline for 3 days or injection of puerarin (25 mg/kg) given 1 h later and then on a daily basis for 3 days. On day 5 after modeling, the kidney tissues were taken for histological observation and detection of cell apoptosis. The renal function indexes including urea nitrogen (BUN), serum creatinine (Scr) and kidney injury molecule 1 (KIM-1) and the levels of tumor necrosis factor (TNF-α) and interleukin 1β (IL-1β) were measured, and the expressions of SIRT1 and NF-κB-p65(acetyl K310) in the renal tissues were detected. RESULTS: Intraperitoneal injection of LPS caused obvious glomerular capillary dilatation, hyperemia, renal interstitial edema, and renal tubular epithelial cell swelling and deformation in the mice. The mouse models of LPS-induced AKI also showed significantly increased renal tubular injury score and renal cell apoptosis (P < 0.01) with increased serum levels of BUN, Scr, KIM-1, TNF-α and IL-1β (P < 0.01), enhanced renal expressions of TNF-α, IL-1β and NF-κB p65(acetyl K310) (P < 0.01) and lowered renal expression of SIRT1 (P < 0.05). Treatment with puerarin effectively alleviated LPS-induced renal interstitial edema and renal tubular epithelial cell shedding, lowered renal tubular injury score (P < 0.01) and renal cell apoptosis rate (P < 0.01), and decreased serum levels of BUN, Scr, KIM, TNF-α and IL-1β (P < 0.01). Puerarin treatment significantly reduced TNF-α, IL-1β and NF-κB p65 (acetyl K310) expression in the renal tissue (P < 0.05) and increased SIRT1 expression by 17% (P < 0.05) in the mouse models. CONCLUSION Puerarin can effectively alleviate LPS-induced AKI in mice possibly by modulating the SIRT1/NF-κB signaling pathway.
Animals ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; Lipopolysaccharides ; Sirtuin 1 ; Tumor Necrosis Factor-alpha ; Acute Kidney Injury ; Disease Models, Animal ; Edema

Parvalbumin interneurons belong to the major types of GABAergic interneurons. Although the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied, the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly interrogated. Through the Cre recombinase-reporter system, we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse brain. We found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions, among which the cortex and thalamus exhibited the most intense parvalbumin signals. In regions such as the striatum and optic tract, even long-range thick parvalbumin projections were detected. Furthermore, in mouse models of temporal lobe epilepsy and Parkinson's disease, parvalbumin fibers suffered both massive and subtle morphological alterations. Our study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.
Mice ; Animals ; Epilepsy, Temporal Lobe/pathology* ; Parvalbumins/metabolism* ; Parkinson Disease/pathology* ; Neurons/metabolism* ; Interneurons/physiology* ; Disease Models, Animal ; Brain/pathology*