[Community-informed connectomics of cortical intrinsic organization in subjective cognitive decline]

Objective: To investigate the intrinsic organization of cortical circuitry in individuals with subjective cognitive decline (SCD) via resting-state functional magnetic resonance imaging (rs-fMRI) connectome analysis and its correlation with cognitive level. Methods: From June 2017 to November 2019, thirty-six middle-aged and elderly individuals with complaints of memory decline and 32 normal controls (NC) were enrolled from communities in Nanjing. We collected cognitive scale performance,T₁-weighted imaging (T₁WI) and rs-fMRI data of all subjects. There were 5 males and 31 females in the SCD group, with an average age of (64±5) years. In the NC group, there were 8 males and 24 females, with an average age of (65±5) years. Preprocessing of rs-fMRI data was conducted, then the cerebral cortex was divided into 333 cortical parcels (nodes) and 10 predefined communities according to the prior template. Further, we established full connection matrices between cortical parcels and calculated the within-module degree (WMD) and participation coefficient (PC) of each node based on the matrices. The WMD and PC values were compared between the SCD and NC groups,and their correlations with cognitive scale performance were analyzed. Results: Compared to the NC group,the SCD group showed increased WMD in the dorsolateral prefrontal cortex (DLPFC)(P<0.05,FDR corrected) and the middle frontal gyrus (P<0.005,uncorrected) of the right frontoparietal network (FPN). The SCD group also showed decreased WMD(P<0.05,FDR corrected) in the superior occipital gyrus of the left visual network (VN) and decreased PC (P<0.005,uncorrected) in the supramarginal gyrus of the left dorsal attention network (DAN). The WMD values in the DLPFC showed significant positive correlations with the auditory verbal learning test (AVLT)short-delayed memory (r=0.364,P=0.029),recognition memory (r=0.364, P=0.029) and the Boston naming test scores (BNT, r=0.356, P=0.033)in the SCD group. The PC values in the supramarginal gyrus were significantly positively correlated with the BNT scores (r=0.413, P=0.012) in the SCD group. Conclusion: Cortical network imbalance and reconstruction characterized by decreased intra-module connectivity of VN and inter-module connectivity of DAN exist in SCD subjects,while increased intra-module connectivity of FPN may serve in a compensatory way for the early cognitive decline.

[Correlation between spatial navigation disorder and white matter hyperintensity in patients with mild cognitive impairment]

Objective: To investigate the relationship between white matter lesions and spatial navigation ability in patients with mild cognitive impairment (MCI). Methods: A total of 32 MCI patients [age (66±11) years, 16 males and 16 females] who were treated in the Affiliated Drum Tower Hospital of Nanjing University Medical School from January 2015 to February 2018 were selected, and matched with age, gender and education level of 28 healthy controls (NC) [age (70±11) years, 19 males and 9 females] underwent spatial navigation ability test and neuropsychology scale evaluation. In the cross-sectional study, all subjects simultaneously underwent 3.0T magnetic resonance three-dimensional liquid inversion recovery sequence and high-resolution T(1) weighted imaging scan. The Wisconsin White Matter Hyperintensities Segmentation Toolbox (W2MHS) was used to automatically mark and extract the volume of the white matter hyperintensity. Results: The average error distances of egocentric virtual (P=0.002) and allocentric virtual (P=0.039) of MCI patients are greater than that of the control group, but the average error distance of mixed (allocentric-egocentric virtual) navigation had no statistic difference between two groups (P=0.070). The volume of the whole white matter hyperintensity, periventricular white matter hyperintensity, and deep white matter hyperintensity showed no significant differences between two groups (all P>0.05). Partial correlation analysis showed that after controlling for age, gender, education level and whole brain volume, the average error distance of mixed (allocentric-egocentric virtual) navigation in MCI patients was positively correlated to the volume of the whole white matter hyperintensity, deep white matter intensity, and periventricular white matter hyperintensity (r=0.469, 0.434, 0.512, all P<0.05). The average error distance of allocentric virtual navigation is positively correlated with the volume of periventricular white matter hyperintensity (r=0.403, P=0.033). There is no correlation between the average error distance of egocentric virtual navigation and the hyperintensity of white matter. Conclusions: The spatial navigation ability of patients with MCI is related to white matter lesions, which is of great significance for further research on the potential biological mechanisms affecting human spatial navigation ability.

[The effect of hypothalamic-pituitary-thyroid axis hormone levels and depression in obstructive sleep apnea-hypopnea syndrome]

Objective: To explore the change of hypothalamic-pituitary-thyroid axis hormones and it's role in depression in obstructive sleep apnea-hypopnea syndrome. Methods: Seventy-three male OSAHS patients [age (39±11) years] and 13 male controls [age (36±7.5) years] were enrolled from August 2013 to May 2017 in the 1(st) Hospital of China Medical University. Overnight polysomnography and depression were assessed. The serum TRH, TSH, FT4 and FT3 levels were measured on the next morning. The relationship between depression and hypothalamic-pituitary-thyroid axis was analyzed. Results: Compared with the control group, severe hypoxia group had higher serum FT3 level [(4.5±0.6) ng/L vs. (5.4±0.7)ng/L, P<0.05)] and depression score (30±7 vs. 40±10, P<0.05). Further analysis revealed that serum FT3 level (5.0±0.5 ng/L vs. 5.5±0.7ng/L, P<0.05) and FT4 level [(16.2±1.9) ng/L vs. (18.2±2.3) ng/L, P<0.05] were lower in the patients with depression than those without. Conclusion: The decrease of serum FT3 and FT4 levels in OSAHS patients with severe hypoxia was closely related to the occurrence of depression.

Primary spinal glioma in children: Results from a referral pediatric institution in Shanghai

PURPOSE

Primary spinal cord glioma is a rare entity especially in children; accounting for less than 10% of all central nervous system tumors. Low grade is the most reported subtype. Treatment modalities have largely evolved; large improvements have been made in the surgical field but also in both of radiotherapy and chemotherapy. Nevertheless, the optimal treatment is yet to be defined.

MATERIAL AND METHODS

A chart review of 11 pediatric patients with a diagnosis of low grade spinal cord glioma at Xhinhua hospital in Shanghai was conducted. A statistical package for Social Sciences Package (SPSS) was used for analysis. Means and standard deviations were calculated. The Kaplan-Meier method was used to analyze overall survival and progression-free survival.

RESULTS

The mean age was 6.7 years (range: 6 months-14.3 years). Revealing symptoms were variable and slowly progressive. The mean duration of symptoms prior to diagnosis was of 7±3.2 months. Astrocytoma was the most commonly reported histological type (seven cases, 63.6%), ependymomas were reported in three cases (27.3%). Surgery was performed in all patients. Subtotal resection concerned the majority of patients (nine patients, 81.8%). Adjuvant radiotherapy was indicated in all cases. A total dose of 39.6Gy was delivered to the whole group. Three patients received adjuvant chemotherapy, of whom two patients had grade III glioma and one patient had a tumor recurrence. Temozolomide-based regimen was the main protocol used for all our patients. The 3 years overall survival rate was 100%, whereas the progression free survival rate was 87.5%. One case relapsed during the next year following completion of treatment.

CONCLUSION

Our preliminary results are consistent with that of other similar published reports, however longer follow up is needed. So are specific recommendations that are still lacking in this setting.

[Ultrastructure changes of liver autolysis]

Ultra-structure changes of autolysis of hepatocyte were studied using transmission electron microscope(TEM). It was found that autolysis started 0.5 hour after death, with the heterochromatin of nuclei shrinking abnormally and smooth endoplasmic reticulum expanding. The changes developed to distinction after 1 h, and progressed continuously after 2 h, 3 h, 4 h and 5 h. It was found that (1) the mitochondria were swelling, its matrix density decreasing and flocculent dense bodies (FDB) emerging; (2) the rough endoplasmic reticulum and perinuclear cistern were expanding. It was suggested that ultra-structure changes of the autolysis be correlated to the postmortem time.

Inhibition of antigen-specific T cell trafficking into the central nervous system via blocking PECAM1/CD31 molecule

Trafficking of antigen-specific T cells into the central nervous system (CNS) is an important initiating step in inflammation in the brain. In spite of the extensive knowledge about the role of adhesion molecules in T cell migration across peripheral vessels, the mechanism of the entry of antigen-specific T cells into the CNS is not known. This work was designed to study the regulatory roles of adhesion molecules in antigen-specific T cell migration into the CNS. Antigen-specific T cells were tracked in an in vivo migration assay using T cell receptor (TCR) transgenic mice having 95% of T cells specific for a defined antigen. pigeon cytochrome c (PCC). TCR transgenic mice were cannulated intraventricularly (IVT) for PCC antigen infusion and cerebrospinal fluid (CSF) sampling. Upon PCC infusion into the CNS, the number of alpha/beta TCR+ Vbeta3+ Mac1- cells in the CSF was characterized in the presence or absence of anti-adhesion molecule reagents. We found that antibodies against VCAM-1 (CD106), VLA-4 (CD49d/CD29), ICAM-1 (CD54), and LFA-1 (CD11a/CD18) did not influence the increased number of antigen-specific T cells in the CSF However, upon intravenous (i.v.) injection, anti-PECAM-1 (CD31) antibody or PECAM-Ig chimeric molecule inhibited the trafficking of alpha/beta TCR+ Vbeta3+ Mac1- cells into the CNS. The expression of PECAM-1 (CD31) was also up-regulated on antigen-specific T cells in a time-dependent manner in vitro upon antigenic stimulation. The antigen-induced activation of T cells in vivo was measured by CD44 and LFA-1 expression and found to be comparable between mPECAMIg-treated mice and wild-type serum control-treated groups. This indicates that CD31 inhibition of antigen-specific T cell accumulation in the CNS is probably not due to a functional inhibition of these cells. Finally, adoptive transfer of CFSE-labeled AND transgenic cells into naïve animals resulted in the accumulation of these cells in the CNS upon PCC IVT immunization that was also inhibited by mPECAMIg treatment. Hence, PECAM-1 (CD31) might play an important role in regulating antigen-specific T cells trafficking in CNS inflammatory diseases.

Antigen-specific T cell trafficking into the central nervous system

The initiation step of cell-mediated immune responses in the central nervous system (CNS) involves the trafficking of the antigen-specific T cells into the brain. To study this trafficking, we developed an in vivo system for studying antigen-specific responses in the CNS. In this assay, T cell receptor (TCR) transgenic mice having 95% of T cells specific for a defined antigen-pigeon cytochrome c (PCC) were cannulated intraventricularly for PCC antigen infusion and cerebrospinal fluid (CSF) sampling. Upon PCC infusion into the CNS, the number of alpha/beta TCR(+) Vbeta3(+) Mac1(-) cells in the CSF was characterized. We found that infusion of antigen into the CSF induced an increased number of antigen-specific T cells in the CNS and activation of antigen-specific T cells in the peripheral blood. Hence, the drainage of CNS antigen into the periphery might play an important role in sustaining autoimmune reactivity in CNS inflammatory diseases.

Influence of adhesion molecule expression by human brain microvessel endothelium on cancer cell adhesion

Cultures of endothelial (En) cells derived from human brain microvessels were established in order to characterize adhesion molecule expression and to assay the adhesion properties of neoplastic cell lines to monolayers of En cells. Low constitutive expression of beta1 integrin (CD29), and ICAM-2 (CD102) was detected on human brain microvessel En cells. The beta1 chain of the VLA integrin family, ICAM-1, E-selectin (CD62E) and VCAM-1 (CD106) but not ICAM-2 and PECAM-1 (CD31) expression was upregulated by IL1-alpha, and TNF-alpha proinflammatory cytokines. High expression of PECAM-1 was found on non-activated human brain EN cells. In order to study the potential role of adhesion molecules in neoplastic cell adhesion two tumor cell lines were chosen. Adhesion of a cell line (DU145) derived from a cerebral metastasis of prostate carcinoma to human brain microvessel En cell monolayers was less pronounced compared to adhesion of a primary prostate carcinoma cell line (ND1). Adhesion of cerebral metastatic neoplastic cell line (DU145) was not significantly influenced by incubation of endothelial cells with different proinflammatory cytokines. The adhesion capability of primary prostate carcinoma line (NDI) was significantly upregulated by TNF-alpha proinflammatory cytokine. Furthermore, the adhesion of ND1 was partly inhibited using anti-E-selectin and VCAM-1 monoclonal antibodies. There was no significant effect of anti-adhesion antibodies on the adhesion characteristics of the cerebral metastatic (DU145) cell line. Our data demonstrate that different mechanisms are involved in the adhesion of neoplastic cells to cerebral En cells and turn our attention to the importance of adhesion molecule expression in the formation of metastases.

An analytical method of ultra-trace tellurium for samples of sea- and environmental-water

This paper presents a method for the concentration of tellurium in sulfhydral cotton fiber. The mechanism of Te-Re catalytic polarographic behaviour has been studied. The optimal conditions of systems are proposed. An analytical procedure of preconcentration with sulfhydral cotton fiber and catalytic polarographic determination of ultra-trace tellurium is presented. This method exhibits good selectivity and is simple and easy. It is also one o;f the most sensitive analytical methods of tellurium at present. The procedure is demonstrated successfully for the determination of background levels of tellurium in a variety of natural water. This is the first reported determination of tellurium in sea water, filling a gap in the literature of oceanic geochemistry. It was found that the content of tellurium in South China sea water is 8 X 10(-10) g/l, that in East China sea water is 4-7 X 10(-10) g/l.