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Chun Cui

Publications and source records attributed to Chun Cui.

9 recordsLinked to original sources

Histological brain alterations following prenatal methamphetamine exposure in rats.

When pregnant women abuse methamphetamine, the foremost concern is the potential adverse effect of this substance on fetal development. Clinical studies in humans have found that exposure to methamphetamine during brain development can cause neurobehavioral abnormalities, such as aggressive behavior, learning problems, and poor social adaptation. In the present study, we examined the effects of prenatal methamphetamine exposure on brain development in rats. The first group of pregnant rats was administered methamphetamine at a dose of 5 mg/kg/day during gestational day (GD 10 to GD 20 [MA]. The second group of pregnant rats was injected with saline vehicle only [SAL]. On GD 21 their fetuses were removed and fetal brains were observed. We found various types of morphological damage in MA fetal brains, including microgyria, ectopia, and hemorrhage. In some cases, abnormal distribution of the leptomeninx, such as breach or accumulation, was observed in addition to these histological abnormalities. Therefore, we examined the expression of laminin, which is an important component of the pia mater, in the fetal brains. However, Western blot analysis revealed that there was no difference in expression amount of laminin in whole fetal brain between the MA and SAL groups. We concluded that methamphetamine use during pregnancy can cause histological brain alterations in fetuses. Morphological alterations of brain seen in the present study and previous human studies following prenatal exposure to methamphetamine might be related to the neurobehavioral abnormalities seen in patients who had been exposed to methamphetamine in utero.

Animals↗

Experimental model for irradiating a restricted region of the rat brain using heavy-ion beams.

Heavy-ion beams have the feature to administer a large radiation dose in the vicinity of the endpoint in the beam range, its irradiation system and biophysical characteristics are different from ordinary irradiation instruments like X-rays or gamma-rays. In order to get clarify characteristic effects of heavy-ion beams on the brain, we have developed an experimental system for irradiating a restricted region of the rat brain using heavy-ion beams. The left cerebral hemispheres of the adult rat brain were irradiated at dose of 50 Gy charged carbon particles (290 MeV/nucleon; 5 mm spread-out Bragg peak). After irradiation, the characteristics of the heavy-ion beams and the animal model were studied. Histological examination and measurement showed that extensive necrosis was observed between 2.5 mm and 7.5 mm depth from the surface of the rat head, suggesting a relatively high dose and uniform dose was delivered among designed depths and the spread-out Bragg peak used here successfully and satisfactorily retained its high-dose localization in the defined region. We believe that our experimental model for irradiating a restricted region of the rat brain using heavy-ion beams is a good model for analyzing regional radiation susceptibility of the brain.

Animals↗

A genetic mouse model carrying the nonfunctional xeroderma pigmentosum group G gene.

A genetic mouse model with a disrupted XPG allele was generated by insertion of neo cassette sequences into exon 3 of the XPG gene by using embryonic stem (ES) cell techniques. The xpg-deficient mice showed distinct developmental characteristics. Their body was marked smaller than that in wild-type littermates since the postnatal day 6, and this postnatal growth failure became more severe with developmental proceeding. Their life span was very short, all of the mutants died by postnatal day 23 after showing great weakness and emaciation. In addition, the mutant homozygous mice also showed some progressive neurological signs, like the lower level of activity and a progressive ataxia. Further examination indicated there was developmental retardation of the brain in the mutant mice. Their brain weight, and thickness of cerebral cortex and cerebellar cortex were significant different from the controls. These characteristics, like small size brain, brain developmental retardation and progressive neurological dysfunctions in the homozygotes were similar to the typical clinical phenotype of the XPG patients and Cockayne syndrome, we believe that the xpgdeficient mice will be an animal model for studying the function of the XP-G protein in nucleotide-excision repair and mechanisms related to the clinic symptoms of XP-G and Cockayne syndrome in humans.

Animals↗

Expression of neural cell adhesion molecule L1 in the brain of rats exposed to X-irradiation in utero.

To gain insight to the cellular and molecular mechanisms involved abnormal neuronal migration induced by irradiation, we investigated expression of neuronal cell adhesion molecule L1 and neuronal migration in the brains through comparison between rats prenatally exposed to X-ray and controls. To observe the pattern of neuronal migration, bromodeoxyuridine (BrdU) was chosen as a marker to label migrating cells. The results showed some of the labeled cells remained in the lower of the cortical plate in the irradiated rats, suggesting that neuronal migration was disrupted by X-ray. To study change of expressing neural cell molecule L1, rat brains were analyzed by SDS-PAGE after isolation of L1 by immunoaffinity chromatography. In the all brain membrane fraction, immunoaffinity purified L1 had bands at 200, 180, 140 and 80 kDa. However, the bands in the irradiated group were very weak when compared with the control. Taking these results into account, abnormal neuronal migration and reduction of expression L1 found in the irradiated brain indicated that migration of neural cells may be largely dependent on radial glial fiber as well as neural cell molecules like L1. A decrease in L1 expression may be one of reasons of abnormal neuronal migration.

Animals↗

Adverse effects of maternal ethanol consumption on development of dorsal hippocampus in rat offspring.

We examined the laminar structure and distribution of mossy fiber terminal fields in the dorsal hippocampus, an important area for spatial learning, in rats exposed to ethanol during gestational days 10-21. Pyramidal cells in the CA3a subfield were loosely packed compared to control rats. Aberrant infra- and intrapyramidal mossy fibers were found in the CA3 region, especially in the CA3a subfield, throughout the dorsal hippocampus of ethanol-exposed rats. Aberrant mossy fiber terminals were observed more frequently in the rostral than the caudal level of the dorsal hippocampus. At the most caudal level of the dorsal hippocampus, disarrangement of pyramidal cells was seen in the CA3c subfield along with disturbed mossy fiber terminals. Immunohistochemical studies revealed that neural cell adhesion molecule (NCAM) was not related to aberrant distribution of mossy fiber terminals after prenatal exposure to ethanol. Parvalbumin immunoreactivity was increased in the dorsal hippocampus of ethanol-exposed rats compared with control rats. Abnormal development of the dorsal hippocampus induced by prenatal ethanol exposure may be associated with the defect of spatial memory seen in fetal alcohol syndrome children and their animal models.

Alcohol Drinking↗

Types and three-dimensional distribution of neuronal ectopias in the brain of mice prenatally subjected to X-irradiation.

The types and three-dimensional distribution of neocortical ectopias following prenatal exposure to X-irradiation were studied by a histological examination and computer reconstruction techniques. Pregnant ICR mice were subjected to X-irradiation at a dose of 1.5 Gy on embryonic day 13. The brains from 30-day-old mice were serially sectioned on the frontal plane at 15 microns, stained with HE and observed with a microscope. The image data for the sections were input to a computer, and then reconstructed to three-dimensional brain structures using the Magellan 3.6 program. Sectional images were then drawn on a computer display at 240 microns intervals, and the positions of the different types of neocortical ectopias were marked using color coding. Three types of neocortical ectopias were recognized in the irradiated brains. Neocortical Lay I ectopias were identified as small patches in the caudal occipital cortex, and were located more laterally in the neocortex in caudal sections than in the rostral sections. Periventricular ectopias were located more rostrally than Lay I ectopias, and were found from the most caudal extent of the presumed motor cortex to the most caudal extent of the lateral ventricle. Hippocampal ectopias appeared as continuous linear bands, and were frequently associated with the anterior parts of the periventricular ectopias.

Animals↗

Distribution of calbindin-D28K immunoreactive neurons in rat primary motor cortex.

Distribution of calbindin-D28K immunoreactive cells in the primary motor area of the adult rat neocortex was studied in the present experiment. In the primary motor cortex, calbindin-D28K immunoreactivity was found in two populations of cortical neurons. One was composed of neurons heavily labeled with anti-calbindin antibody, which were present in two bands corresponding to cortical layers II-III, and V. The morphological types of these cells were varied; they had oval, fusiform or mutiangular somata. The proximal dendrites of the heavily stained cells showed that these cells were non-pyramidal neurons, and they were either bitufted or multipolar cells. The other was a weakly stained population, mainly concentrated in layers II and III, that also contained pyramidal neurons. In addition, one outstanding feature of the neuropil staining deep to layer II was the labeling of the long, vertically oriented bundles of immunoreactive processes. Such a distinct pattern of calbindin-D28K immunoreactive neurons in the primary motor cortex suggests a relatively high density of calcium channels exists in the superficial layers of the rat primary motor cortex.

Animals↗

Normal and abnormal neuronal migration in the developing cerebral cortex.

Neuronal migration is the critical cellular process which initiates histogenesis of cerebral cortex. Migration involves a series of complex cell interactions and transformation. After completing their final mitosis, neurons migrate from the ventricular zone into the cortical plate, and then establish neuronal lamina and settle onto the outermost layer, forming an "inside-out" gradient of maturation. This process is guided by radial glial fibers, requires proper receptors, ligands, other unknown extracellular factors, and local signaling to stop neuronal migration. This process is also highly sensitive to various physical, chemical and biological agents as well as to genetic mutations. Any disturbance of the normal process may result in neuronal migration disorder. Such neuronal migration disorder is believed as major cause of both gross brain malformation and more special cerebral structural and functional abnormalities in experimental animals and in humans. An increasing number of instructive studies on experimental models and several genetic model systems of neuronal migration disorder have established the foundation of cortex formation and provided deeper insights into the genetic and molecular mechanisms underlying normal and abnormal neuronal migration.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

Drinking and drinking patterns and health status in the general population of five areas of China.

AIMS: To understand drinking patterns, health status related to drinking and the level of unrecorded alcoholic beverage consumption for the general population living in five areas of China in 2001. METHODS: By cluster sampling, 24992 community residents aged 15 years or older were interviewed by trained psychiatrists using structured questionnaires provided by WHO. RESULTS: The 1-year drinking rate was 59.0%, and the point prevalence rate of dependence was 3.8%. The average annual consumption of pure alcohol was 4.47 l. The 1-year morbidity from gastritis/ulcer in the whole sample was 7.9%, which associated nonlinearly to alcohol intake, and heart disease and cerebral infarction/cerebral haemorrhage showed V-shaped curve relationships. CONCLUSIONS: The rate of alcohol use was higher in men than in women, and the annual alcohol consumption per capita was higher than that in the 1990s in the selected areas. Alcohol consumption plays a role in the development of alcohol-related physical diseases.

Adult↗