Objective To explore the correlation between depression and brain activation in patients with major depressive disorders(MDD) during the Verbal Fluency Task(VFT) and the Tower of London Test(TOL) using near-infrared spectroscopy(NIRS). Methods Thirty-five depression patients and thirty-five healthy controls matched with age and sex were both measured of oxygenated hemoglobin concentration(oxy-Hb) changes in the prefrontal cortex (PFC) by NIRS during VFT and TOL tasks. The severity of depression and anxiety symptoms were assessed by Hamilton Rating Scale for Depression (HAMD), Hamilton Anxiety Rating Scale (HAMA) and Beck Depression Rating Scale(BDI). The average [oxy-Hb] changes in each region of interest (ROI) were compared between the two groups by using an independent sample t test. Then the correlation between the average (oxy-Hb) changes of ROI during the task tests and the scores of HAMD 、HAMA and BDI was explored by Spearman analysis in MDD group. Results During VFT and TOL, the average (oxy-Hb) changes in ROI of dorsolateral PFC and the ventrolateral PFC were significantly lower in MDD group ( (0.18±0.19) mmol·mm vs. (0.29±0.22) mmol·mm, (-0.01 ± 0.16) mmol · mm vs. (0.08 ± 0.14) mmol · mm;t=-2.195,P=0.032, t=-2.448,P=0.017). The Spearman correlation analysis found that the average (oxy-Hb) changes in the frontopolar of MDD during TOL were negatively associated with the total scores of HAMD and BDI(r=-0.354,P=0.037;r=-0.495,P=0.003), and the average (oxy-Hb) changes in the left lateral PFC in MDD during TOL were negatively associated with the total scores of BDI (r=-0.349,P=0.040). Conclusions The function of frontopolar and lateral PFC in MDD is significantly impaired. Activation in the frontopolar and the left lateral PFC during TOL task will be much less if the depression becomes more severe. By using NIRS, TOL may be a good active task to measure the brain function.

Objective To explore the correlation between depression and brain activation in patients with major depressive disorders(MDD) during the Verbal Fluency Task(VFT) and the Tower of London Test(TOL) using near-infrared spectroscopy(NIRS). Methods Thirty-five depression patients and thirty-five healthy controls matched with age and sex were both measured of oxygenated hemoglobin concentration(oxy-Hb) changes in the prefrontal cortex (PFC) by NIRS during VFT and TOL tasks. The severity of depression and anxiety symptoms were assessed by Hamilton Rating Scale for Depression (HAMD), Hamilton Anxiety Rating Scale (HAMA) and Beck Depression Rating Scale(BDI). The average [oxy-Hb] changes in each region of interest (ROI) were compared between the two groups by using an independent sample t test. Then the correlation between the average (oxy-Hb) changes of ROI during the task tests and the scores of HAMD 、HAMA and BDI was explored by Spearman analysis in MDD group. Results During VFT and TOL, the average (oxy-Hb) changes in ROI of dorsolateral PFC and the ventrolateral PFC were significantly lower in MDD group ( (0.18±0.19) mmol·mm vs. (0.29±0.22) mmol·mm, (-0.01 ± 0.16) mmol · mm vs. (0.08 ± 0.14) mmol · mm;t=-2.195,P=0.032, t=-2.448,P=0.017). The Spearman correlation analysis found that the average (oxy-Hb) changes in the frontopolar of MDD during TOL were negatively associated with the total scores of HAMD and BDI(r=-0.354,P=0.037;r=-0.495,P=0.003), and the average (oxy-Hb) changes in the left lateral PFC in MDD during TOL were negatively associated with the total scores of BDI (r=-0.349,P=0.040). Conclusions The function of frontopolar and lateral PFC in MDD is significantly impaired. Activation in the frontopolar and the left lateral PFC during TOL task will be much less if the depression becomes more severe. By using NIRS, TOL may be a good active task to measure the brain function.

BACKGROUND:The studies have shown that the mesenchymal stem cel s derived from bone marrow and umbilical cord can be continuously cultured in vitro, and maintain the characteristics of stem cel s. The mesenchymal stem cel s can differentiate into hepatocyte-like cel s after“cocktail”induction by various cytokines. OBJECTIVE:To further identify whether umbilical cord-derived mesenchymal stem cel s in vitro co-cultured with normal hepatocytes can differentiate into hepatocyte-like cel s, and to investigate the differentiation method. METHODS:Mesenchymal stem cel s were isolated from human umbilical cord with adherent method, and the surface markers of umbilical cord-derived mesenchymal stem cel s were detected with flow cytometry. The umbilical cord-derived mesenchymal stem cel s were co-cultured with liver LO2 cel s without adding exogenous inducers. The expressions of alpha-fetoprotein, albumin and human cytokeratin 19 mRNA of hepatocyte specific markers were detected with reverse transcription PCR at 7, 14 and 21 days after culture, and periodic acid-Schiff staining was used to identify the functions. RESULTS AND CONCLUSION:Mesenchymal stem cel s could isolated from human umbilical cord successful y, showing fibroblastic morphology and adherent cel characterization. Among these cel s, 96.02%cel s were CD29 positive cel s and 96.6%cel s were CD105 positive cel s. The percentage of CD34 negative cel s was 99.65%. The percentage of CD105+CD29+double positive cel s was 94.84%. The mRNA of alpha-fetoprotein was found on the 7th day after co-cultured with LO2 cel s, and the mRNA of albumin and human cytokeratin 19 were found on the 14th day. After co-cultured for 21 days, the alpha-fetoprotein mRNA could not be observed in the co-culture group. The expressions of albumin and human cytokeratin 19 were increased at 14 days. After co-cultured for 21 days, the glycogen staining was positive. Umbilical cord-derived mesenchymal stem cel s can differentiate into hepatocyte-like cel s after co-cultured with normal hepatocytes.