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Chun Cui

Publications and source records attributed to Chun Cui.

5 recordsLinked to original sources

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↗

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↗