Zhenping Li

Sexual dimorphism and asymmetry in human cerebellum: An MRI-based morphometric study

Structural sexual dimorphism and asymmetry in human cerebellum have been described in previous research, but results remain inconclusive or even conflicting. In this study, gender differences and hemispheric asymmetries in global and regional human cerebellum gray matter (GM) were estimated in an age-matched sample (n=112) of young Chinese adults. An optimized voxel-based morphometry (VBM) in spatial unbiased infratentorial template (SUIT) space together with an automated atlas-based volumetric approach were performed for mapping regional gray matter (GM) gender-related differences across the entire cerebellum. The two methods provided consistent findings on gender differences. The cerebellar GM volume was significantly larger in the anterior and middle posterior lobes of male group. In addition, a trend of greater GM volume in lateral posterior lobe of female group was observed. With the created symmetric cerebellar template, the asymmetric properties of cerebellar hemisphere were also assessed by VBM analysis, showing rightward asymmetry distributed in most cerebellar lobules and leftwards asymmetry distributed in the lobules around the medial posterior lobe. Gender differences in males showed higher leftward asymmetry sparsely within a few lobules and lower rightward asymmetry mainly within lobule Crus II, as compared with females. The acquired detailed morphologic knowledge of normal human cerebellum could establish a baseline for comparison with pathologic changes in the cerebellum. Moreover, our results might help to address controversies in thestudy of sexual dimorphisms and asymmetric patterns in human cerebellum.

Effects of Ginkgolide B on 6-OHDA-induced apoptosis and calcium over load in cultured PC12

Ginkgolide B, one of the major components of Ginkgo biloba extracts, is a potent platelet‐activating factor (PAF) receptor antagonist, which is also regarded as having neuroprotective effects on the CNS. The aim of this research is to observe the effects of Ginkgolide B on the PC12 apoptosis induced by 6‐hydroxydopamine (6‐OHDA) and to explore whether these effects are related to the changes of intracellular Ca2+ and Calbindin D28K mRNA in PC12 cells. In the present work, the damage of PC12 cells was induced by 100 μM 6‐OHDA. The cells survival rate was examined by MTT assays. The intracellular free calcium concentration in PC12 cells was measured by using the fluorescent Ca2+ indicator fluo‐3/AM. Semi‐quantitative reverse transcriptase‐polymerase chain reaction (RT‐PCR) was employed to determine the expression of Calbindin D28K mRNA in PC12. The data show that the Ginkgolide B inhibited PC12 cells apoptosis induced by 6‐OHDA in a dose‐dependent manner, and decreased the activity of caspase‐3. In addition, Ginkgolide B increased the expression of Calbindin D28K mRNA and inhibited 6‐OHDA‐induced elevation in the intracellular calcium concentration. Our results showed that the Ginkgolide B inhibited the apoptosis of PC12 induced by 6‐OHDA, and the protective effects of Ginkgolide B on PC12 cells are mediated, at least in part, by up‐regulating the Calbindin D28K mRNA and by decreasing the intracellular calcium concentration.

The pineal volume: a three-dimensional volumetric study in healthy young adults using 3.0 T MR data

It is usually difficult to distinguish small pineal tumors via routine or enhanced magnetic resonance (MR) scan. The knowledge of normal pineal size is helpful to detect small pineal lesions, while very few true volumetric data of pineal glands have been reported. Therefore, we obtained the accurate reference range of normal pineal volumes in 112 individuals aged 20–30 years recruited randomly from a healthy community sample. Transverse and sagittal 3.0 T magnetic resonance data were obtained using three‐dimensional (3D) T1‐weighted FSPGR and T2‐weighted SE sequences. True pineal volumes were measured from T1‐weighted images, while estimated volumes were calculated using pineal length, width and height. All the glands were divided into three types according to the maximum inner diameter of pineal cysts. The prevalence of asymptomatic pineal cyst is 25.00%, with a slight female predominance. In the whole sample, we found no gender differences of pineal volume, but a significant gender difference of pineal volume index. A significant correlation between pineal volume and asymptomatic cyst was found. After excluding cases with big pineal cysts, there were significant correlations between pineal volume and head circumference, body height and body weight, respectively. This study suggests that asymptomatic pineal cysts may exert an important influence on pineal volume.

D-β-hydroxybutyrate inhibits the apoptosis of PC12 cells induced by 6-OHDA in relation to up-regulating the ratio of Bcl-2/Bax mRNA

D-beta-hydroxybutyrate (DbetaHB) is a predominant member of ketone bodies produced by hepatocytes and, to a lesser extent, by astrocytes. It is an alternative source of energy in the brain when glucose supply is depleted such as during starvation. It has been reported that ketone bodies could protect dopaminergic culture. However, the biological function of DbetaHB in Parkinson disease (PD) is still unclear. In the present work, we investigated the role of DbetaHB in protecting rat pheochromocytoma (PC12) cells from apoptosis induced by 6-Hydroxydopamine (6-OHDA). DbetaHB rescued PC12 cells from apoptotic death induced by 6-OHDA by MTT assay, acridine orange (AO) staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining and the activity of caspase-3. DbetaHB prevented the decrease of cell viability and the increase of caspase-3 activity induced by 6-OHDA in a dose-dependent manner in PC12 cells. AO and TUNEL staining showed that DbetaHB prevented the apoptosis of PC12 cells induced by 6-OHDA. The ratio of Bcl-2/Bax at mRNA levels, which regulates the apoptosis of PC12 cells when exposed to 6-OHDA, increased when DbetaHB was preincubated. The data showed that DbetaHB inhibited the apoptosis of PC12 cells induced by 6-OHDA in relation to up-regulating the ratio of Bcl-2/Bax mRNA.

α-Synuclein knockdown attenuates MPP + induced mitochondrial dysfunction of SH-SY5Y cells

Alpha-synuclein is one of the main constituents of Lewy bodies and plays an important role in the pathology of Parkinsons disease. Mutation or overexpression of alpha-synuclein causes Parkinsons disease, and downregulation of alpha-synuclein resists MPP(+)-induced cell death, but the mechanism remains elusive. In this study, we attempted to explore the effect of alpha-synuclein knockdown on mitochondrial function in MPP(+)-treated SH-SY5Y cells. We reconstructed the short hairpin RNA expression vector, pGenesil-2, specially targeting alpha-synuclein mRNA, and it was stably transfected into SH-SY5Y cells. Cell viability, nuclear morphology, and mitochondrial membrane potential were then detected, and the expression of alpha-synuclein, cytochrome c, Bcl-2 and Bax were analyzed by Western blotting. The results showed that after exposure to 500 microM MPP(+) for 24 h, about 41.0+/-1.5% control cells showed low mitochondrial membrane potential. However, the percentage was 13.6+/-1.2% in MPP(+) treated alpha-synuclein knockdown cells. MPP(+) induced cytochrome c release significantly, which was about 3.1-fold compared with that of control. However, in alpha-synuclein knockdown cells, the release of cytochrome c was blocked, which was about 1.4-fold compared with that of control. The Bcl-2/Bax ratio of SH-SY5Y cells reduced to 35.5+/-3.8% after MPP(+) treatment, and this ratio was 85.2+/-3.0% in MPP(+) treated alpha-synuclein knockdown cells. These data suggest that knockdown of alpha- synuclein might be an effective means in rescuing MPP(+)-induced mitochondrial dysfunction of SH-SY5Y cells.

Development of the human fetal cerebellum in the second trimester: a post mortem magnetic resonance imaging evaluation

The cerebellum is one of the most important structures in the posterior cranial fossa, but the characterization of its development by magnetic resonance imaging (MRI) is incomplete. We scanned 40 fetuses that had no morphological brain disorder at 14–22 weeks of gestation using 7.0 T MRI. Amira 4.1 software was used to determine morphological parameters of the fetal cerebellum, which included the cerebellar volume (CV), transverse cerebellar diameter (TCD), and the length and width of the vermis. The relationship between these measurements and gestational age (GA) was analysed. We found that the primary fissure was visible at week 14 of gestation. From week 16, the prepyramidal fissure, the secondary fissure and the dentate nucleus could be identified. The posterolateral fissure and the fourth ventricle were recognized at week 17, whereas the tentorium of the cerebellum was visible at week 20. The relationships between GA and CV, TCD, and the width and length of the vermis were described adequately by second‐order polynomial regression curves. The ratios between TCD and vermis length and between TCD and vermis width decreased with GA. These results show that 7.0 T MRI can show the trajectory of cerebellar development clearly. They increase our understanding of normal cerebellar development in the fetus, and will facilitate the diagnosis of pathological intrauterine changes in the cerebellum.

Cerebral glucose metabolism: Influence on perihematomal edema formation after intracerebral hemorrhage in cat models

Background: Most intracerebral hemorrhage (ICH) imaging studies focus on structural brain changes. Stereotactic neuroimaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) are helpful in the diagnosis of ICH, monitoring the subsequent recovery and investigating its functional mechanisms. Purpose: To explore the influence of the changes in cerebral glucose metabolism on perihematomal edema formation in an experimental cat model of ICH. Material and Methods: Forty-eight cats were divided into 1 sham operation group (6 cats) and 7 ICH model groups (42 cats)”. The ICH model groups were injected with 1.0 ml autologous nonheparinized blood into their thalami using accurate stereotactic guidance apparatus. MRI and 18F-fluorodeoxyglucose (FDG) PET/CT scans were acquired at 2, 6, 12, 24, 48, 72, and 120 h following the intervention. Pearsons correlation test was used to evaluate the association between T2-weighted signal intensity and the edema volume. Students t test and q test were used to identify the times of significant temporal changes. Results: The volume of perilesional edema did not significantly increase from 2 h to 12 h after ICH, but then increased by 229.4% at 24 h, peaked (by 273.5%), and steadily decreased by 72 h. The FDG intensity in perihematomal edema tissues was markedly reduced 2 h after ICH on PET images, reached its lowest level at 12 h, and then steadily increased at 24 h and 48 h. The changes of standard absorption value (SUV) in perihematomal edema were consistent with those of FDG intensity. Conclusion: Perihematomal glucose metabolism abnormalities have a close relationship with the formation of vasogenic edema. Furthermore, abnormal glucose metabolism may impair capillary integrity and increase blood–brain barrier permeability.

Sectional anatomy of the peritoneal reflections of the upper abdomen in the coronal plane.

Purpose: The purpose of this study was to provide practical anatomic data for the imaging diagnosis and surgical treatment of the diseases of the subphrenic spaces. Methods: The sectional anatomy of the subphrenic spaces on the coronal plane was investigated on serial coronal sections of the upper abdomen of 30 Chinese adult cadavers. Results: The space between the anterior margin of gastropancreatic fold and the posterior layer of hepatogastric ligament is the only direct pathway between the superior and inferior recesses of the lesser sac. That pathway can be divided into 3 types on the coronal plane. The right layer of the gastrophrenic ligament is continuous with the posterior layer of the lesser omentum, and its left layer is continuous with the right layer of the phrenosplenic ligament and the posterior layer of the gastrosplenic ligament. The gastropancreatic fold is continued to the left and right layers of the gastrophrenic ligament upwards. The bare area of the stomach is located between the left and right layers of the gastrophrenic ligament; its existing rate is 100%. The bare area of the spleen is located among the phrenosplenic ligament, gastrosplenic ligament, splenorenal ligament, and splenocolic ligament. Its greatest width exists between the two layers of the splenorenal ligament. It can be divided into the splenic hilus and splenorenal parts. Conclusion: The coronal section is dominant to show the anatomic relationships of the gastrophrenic ligaments and the gastropancreatic folds, and the bare area of the stomach.

Research on the Propagation of the Crack Parallel to and Lying on the Interface in the Cermet Cladding Part

Taking the interface crack in the cermet cladding part as the study object, a new comparative propagation property parameter (CPPP) CP suitable to judge the interface crack propagation direction in the cladding part is proposed. The interface crack propagation criterion is established. Based on it, the theoretical research on the parameters (CP1, CP2 and CPi) for the crack parallel to and lying on the interface propagating to the clad, to the substrate, and along the interface is carried out. The interface crack propagation law is investigated with an example. The research results show that the crack will more easily deflect to the clad.

Sectional anatomy of the fetal brain in uterus at term on the sagittal plane.

OBJECTIVE To provide sectional anatomic data for the precise localization of developmental malformation of fetal brain in sagittal magnetic resonance imaging (MRI). METHOD After abdominal and pelvic MRI scanning, the gravid specimen was cut into serial sagittal slices in correspondence with MRI in a low temperature laboratory to demonstrate the structures of fetal brain. RESULT (1) Directional determination of the sloping and rotating fetal head. From the serial sagittal sections of pregnant cadaver at term, we concluded that, the longitudinal lying and cephalic presentation fetal had run into maternal pelvis, and rotated and sloped to right. Anteroposterior position and median sagittal plane of the fetal was in correspondence with his mothers. (2) Seven serial sagittal sections of the fetal brain were obtained through lateral surface of the right cerebral hemisphere, lateral sulcus, internal capsule, median sagittal plane, middle cerebellar peduncle, brainstem, and lateral surface of the left cerebral hemisphere. CONCLUSION Through the comparison study between sagittal sections and corresponding MRI of fetal brain at term, we could obtain morphological anatomic structures and MRI of fetal brain, providing morphological demonstration of the intrauterine development of fetal brain and auxiliary diagnosis of ultrasound and MRI in pregnant woman.