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    05 March 2012, Volume 7 Issue 7 Previous Issue    Next Issue
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    Dorsal root ganglion progenitors differentiate to gamma-aminobutyric acid- and choline acetyltransferase-positive neurons
    Lingli Yu, Yindi Ding, Ambre Spencer, Ji Ma, Ruisheng Lu, Brian B. Rudkin, Chonggang Yuan
    2012, 7 (7):  485-491. 
    Abstract ( 199 )   PDF (304KB) ( 934 )   Save

    This study examined the isolation and differentiation of dorsal root ganglion progenitor cells for therapeutic use in neurodegenerative diseases. Rat embryonic dorsal root ganglia progenitors were isolated and purified using the differential adhesion method combined with cytosine arabinoside treatment. After culture in serum-free medium supplemented with B27, basic fibroblast growth factor and epidermal growth factor, these cells remained viable and survived for more than 18 months in vitro. Most cells differentiated to neurons that were immunoreactive for gamma-aminobutyric acid and choline acetyltransferase as detected by immunohistochemical staining. In addition, nerve growth factor and neurotrophic tyrosine kinase receptor expression were also observed in dorsal root ganglion progenitors and differentiated cells. K252a, an inhibitor that blocks nerve growth factor-induced signaling, inhibited cell survival, suggesting the possible existence of a nerve growth factor autocrine loop in these proliferating cells.

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    The gap junction blocker carbenoxolone enhances propofol and sevoflurane-induced loss of consciousness
    Zhigang Liu, Yongfang Liu, Bo Zhao, Li Du, Zhongyuan Xia, Xiangdong Chen, Tao Luo
    2012, 7 (7):  492-495. 
    Abstract ( 178 )   PDF (116KB) ( 851 )   Save

    General anesthetics induce loss of consciousness by inhibiting ascending arousal pathways, and they interfere with gap junction electrical coupling. The present study aimed to determine whether inhibition of gap junction-mediated signaling could influence general anesthetic-induced loss of consciousness. The general anesthetics sevoflurane and propofol were used. Intracerebroventricular administration of carbenoxolone, a gap junction blocker, significantly decreased the time to loss of the righting reflex (P < 0.05), but prolonged the time to recovery of the reflex (P < 0.05). Moreover, intracerebroventricular administration of carbenoxolone increased the sensitivity to sevoflurane, with a leftward shift of the loss of righting reflex dose-response curve, and decreased the 50% effective concentration of sevoflurane. These results suggest that the gap junction blocker carbenoxolone enhances propofol and sevoflurane-mediated general anesthesia.

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    Effect of Rho-kinase pathway on neurite outgrowth of rat hippocampal neurons under atomic force microscopy
    Jing Chen, Hu Hao, Guoqing Guo, Sitao Li, Xin Xiao
    2012, 7 (7):  496-500. 
    Abstract ( 218 )   PDF (183KB) ( 856 )   Save

    Hippocampal neurons of neonatal rats were cultured in serum-free culture medium for 5 days in vitro, and treated with the Rho-kinase inducer lysophosphatidic acid. Atomic force microscopy revealed that the numbers of level-1, -2 and -3 neurites protruding from rat hippocampal neurons was significantly reduced. After treatment with the Rho kinase inhibitor Y27632, a significant increase in the numbers of these neurites was observed. Our experimental findings indicate that the Rho-kinase pathway is closely associated with the neurites of hippocampal neurons.

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    Activation of brain areas following ankle dorsiflexion versus plantar flexion Functional magnetic resonance imaging verification
    Tianyu Jiang, Weiping Wu, Xinglin Wang, Changshui Weng, Qiuhua Wang, Yanmei Guo
    2012, 7 (7):  501-505. 
    Abstract ( 216 )   PDF (181KB) ( 1238 )   Save

    Changes in activated areas of the brain during ankle active dorsiflexion and ankle active plantar flexion were observed in six healthy subjects using functional magnetic resonance imaging. Excited areas of ankle active dorsiflexion involved the bilateral primary motor area and the primary somatosensory area, as well as the bilateral supplementary sensory area, the primary visual area, the right second visual area, and the vermis of cerebellum. Excited areas of ankle active plantar flexion included the ipsilateral supplementary motor area, the limbic system, and the contralateral corpus striatum. Fine movements of the cerebral cortex control the function of the ankle dorsiflexion to a larger extent than ankle plate flexion, and the function of ankle plate flexion is more controlled by the subcortical area.

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    Differentiation of fetal pancreatic stem cells into neuron-like and islet-like cells in vitro
    Xiufeng Hua, Yanwei Wang, Peiwen Lian, Shouxin Zhang, Jianyuan Li, Haiyan Wang, Shulin Chen, Wei Gao
    2012, 7 (7):  506-510. 
    Abstract ( 298 )   PDF (281KB) ( 836 )   Save

    Pancreatic stem cells were isolated and cultured from aborted human fetal pancreases of gestational age 14-20 weeks. They were seeded at a density of 1 × 104 in serum-free media for differentiation into neuron-like cells, expressing β-tubulin III and glial fibrillary acidic protein. These neuron-like cells displayed a synapse-like morphology and appeared to form a neuronal network. Pancreatic stem cells were also seeded at a density of 1 × 105 for differentiation into islet-like cells, expressing insulin and glucagon, with an islet-like morphology. These cells had glucose-stimulated secretion of human insulin and C-peptide. Results suggest that pancreatic stem cells can be differentiated into neuron-like and islet-like cells.

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    Directional induction of dopaminergic neurons from neural stem cells using substantia nigra homogenates and basic fibroblast growth factor
    Jintao Li, Qi Yan, Yiliu Ma, Zhongtang Feng, Tinghua Wang
    2012, 7 (7):  511-516. 
    Abstract ( 199 )   PDF (167KB) ( 863 )   Save

    To date, complex components of available reagents have been used for directional induction of neural stem cells into dopaminergic neurons, resulting in a poor ability to repeat experiments. This study sought to investigate whether a homogenate of the substantia nigra of adult rats and/or basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons. Tyrosine hydroxylase-positive cells were observed exclusively after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor for 48 hours in vitro. However, in the groups treated with homogenate supernatant or basic fibroblast growth factor alone, tyrosine hydroxylase expression was not observed. Moreover, the content of dopamine in the culture medium of subventricular zone neurons was significantly increased at 48 hours after induction with the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor. Experimental findings indicate that the homogenate supernatant of the substantia nigra from adult rats and basic fibroblast growth factor could directionally induce neural stem cells derived from the subventricular zone of embryonic rats to differentiate into dopaminergic neurons in the substantia nigra with the ability to secrete dopamine.

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    Expression of acetylated histone 3 in the spinal cord and the effect of morphine on inflammatory pain in rats
    Hua Li, Changqi Li, Ruping Dai, Xudan Shi, Junmei Xu, Jianyi Zhang, Xinfu Zhou, Zhiyuan Li, Xuegang Luo
    2012, 7 (7):  517-522. 
    Abstract ( 216 )   PDF (394KB) ( 881 )   Save

    In this study, a rat model of inflammatory pain was produced by injecting complete Freund’s adjuvant into the hind paw, and the expression of acetylated histone 3 in the spinal cord dorsal horn was examined using immunohistochemical staining. One day following injection, there was a dramatic decrease in acetylated histone 3 expression in spinal cord dorsal horn neurons. However, on day 7, expression recovered in adjuvant-injected rats. While acetylated histone 3 labeling was present in dorsal horn neurons, it was more abundant in astrocytes and microglial cells. The recovery of acetylated histone 3 expression was associated with a shift in expression of the protein from neurons to glial cells. Morphine injection significantly upregulated the expression of acetylated histone 3 in spinal cord dorsal horn neurons and glial cells 1 day after injection, especially in astrocytes, preventing the transient downregulation. Our results indicate that inflammatory pain induces a transient downregulation of acetylated histone 3 in the spinal cord dorsal horn at an early stage following adjuvant injection, and that this effect can be reversed by morphine. Thus, the downregulation of acetylated histone 3 may be involved in the development of inflammatory pain.

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    Kappa opioid receptor antagonist and N-methyl-D- aspartate receptor antagonist affect dynorphin- induced spinal cord electrophysiologic impairment
    Yu Chen, Liangbi Xiang, Jun Liu, Dapeng Zhou, Hailong Yu, Qi Wang, Wenfeng Han, Weijian Ren
    2012, 7 (7):  523-527. 
    Abstract ( 211 )   PDF (143KB) ( 704 )   Save

    The latencies of motor- and somatosensory-evoked potentials were prolonged to different degrees, and wave amplitude was obviously decreased, after injection of dynorphin into the rat subarachnoid cavity. The wave amplitude and latencies of motor- and somatosensory-evoked potentials were significantly recovered at 7 and 14 days after combined injection of dynorphin and either the kappa opioid receptor antagonist nor-binaltorphimine or the N-methyl-D-aspartate receptor antagonist MK-801. The wave amplitude and latency were similar in rats after combined injection of dynorphin and nor-binaltorphimine or MK-801. These results suggest that intrathecal injection of dynorphin causes damage to spinal cord function. Prevention of N-methyl-D-aspartate receptor or kappa receptor activation lessened the injury to spinal cord function induced by dynorphin.

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    Genetic relationship between serum pregnancy-associated plasma protein-A gene polymorphism and ischemic cerebrovascular disease in a Northern Han Chinese population
    Haiping Wang, Yan Song, Chen Zhang, Jingjing Zhan, Rui Zhang, Haiji Wang
    2012, 7 (7):  528-533. 
    Abstract ( 185 )   PDF (215KB) ( 907 )   Save

    The present study recruited 193 patients with ischemic cerebrovascular disease from Inpatient and Outpatient Departments at the Affiliated Hospital of Qingdao University Medical College, China from August 2008 to May 2010, as well as 120 healthy volunteers from the Medical Examination Center at the Affiliated Hospital of Qingdao University Medical College, China, who served as controls for this study. Patients and control subjects were from the Han population in northern China. Enzyme- linked immunosorbent assay analysis revealed increased levels of serum pregnancy-associated plasma protein-A (PAPP-A) in ischemic cerebrovascular disease patients compared with healthy controls. In addition, the patients exhibited greater frequency of genotype CC and C alleles in a missense A/C (Tyr/Ser) polymorphism (dbSNP: rs7020782) of exon 14 in the PAPP-A gene. Multiple-factor logistic regression analysis on correction of age, gender, history of smoking, hypertension, diabetes mellitus, hypercholesteremia, and ischemic stroke family history showed that the risk for ischemic cerebrovascular disease in the population without the A allele at the A/C genetic locus in exon 14 of the PAPP-A was 2-folds greater than the population expressing the A allele. These experimental findings suggested that ischemic cerebrovascular disease correlated with the C allele in exon 14 of PAPP-A. In addition, the A allele is likely a protective gene; individuals carrying the A allele were less prone to ischemic cerebrovascular disease compared with individuals without the A allele.

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    Functional outcomes after home-based rehabilitation for heroin-induced spongiform leukoencephalopathy
    Xuhong Li, Liming Deng, Bin Ye
    2012, 7 (7):  534-538. 
    Abstract ( 172 )   PDF (271KB) ( 764 )   Save

    A 22-year-old man with a 2-year history of heroin vapor inhalation developed spongiform leukoencephalopathy and underwent clinical and home-based rehabilitative treatments. Activities of daily living were measured using the Functional Independence Measure at discharge and at 6, 12, and 24 months after discharge. His neurological symptoms gradually disappeared with rehabilitative treatment, and the functional scale scores increased from 55 on admission to 105 at 24 months after discharge. These results suggest that home-based rehabilitation was effective in ameliorating the pathology and improving activities of daily living in this patient with heroin-induced spongiform leukoencephalopathy.

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    Long-term prognosis and prognostic determinants of patients with first attack of mild and moderate ischemia at Beijing community hospitals
    Xianghua Fang, Liming Li, Xinqing Zhang, Hongjun Liu, Hongmei Zhang, Xiaoming Qin
    2012, 7 (7):  540-545. 
    Abstract ( 205 )   PDF (151KB) ( 807 )   Save

    A total of 710 patients with first-ever ischemic stroke were consecutively recruited between January 2003 and December 2004 from five community hospitals/stations in five districts of Beijing, China. As of December 31, 2008, a total of 2 477 person-years were followed-up. During the five-year follow-ups, 117 adverse events occurred, including all-cause death and acute cardiovascular events (recurrent stroke, acute myocardial infarction, and sudden death). The five-year cumulative mortality rate was 2.18/100 person-years (54 cases), with 3.88/100 person-years (96 cases) of acute cardiovascular events and 3.02/100 person-years (75 cases) of recurrent stroke. Multiple factor analyses using the Cox proportional hazards ratio models showed that age, diabetes, and dependence of activities of daily living were independent predictors for death, acute cardiovascular disease events, or recurrent stroke. The results demonstrated that recurrent stroke was a major vascular disease that affected the prognosis of mild or moderate stroke patients. Secondary prevention of stroke patients should include active management of vascular risk factors and rehabilitation.

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    Relationship between the -455G/A and -148C/T polymorphisms in the beta-fibrinogen gene and cerebral infarction in the Xinjiang Uygur and Han Chinese populations
    Xiaoning Zhang, Yanyun Li, Xuebing Guo, Lei Du, Jianhua Ma
    2012, 7 (7):  546-551. 
    Abstract ( 371 )   PDF (226KB) ( 1005 )   Save

    We sought to investigate the correlation between the -455G/A and -148C/T polymorphisms of the β-fibrinogen gene and plasma fibrinogen levels in patients with cerebral infarction and in healthy subjects among the Xinjiang Uygur and Han Chinese populations, by using polymerase chain reaction-restriction enzyme digestion analysis. Results showed that there were no statistically significant differences in the distributions of the -455G/A genotype and allele frequency between the Uygurs and the Han. Plasma fibrinogen levels in cerebral infarction patients among the Uygurs and the Han were higher than those among healthy subjects. In particular, the frequencies of the -455G/A AA and -148C/T TT genotypes were significantly higher than in healthy subjects. Individuals carrying the A or T allele had a higher incidence of cerebral infarction compared with those carrying the G or C allele. Our experimental findings indicate that the -148C/T and -455G/A polymorphisms are associated with cerebral infarction in Xinjiang Uygur and Han Chinese subjects. The susceptibility- conferring alleles are -148T and -455A, and the susceptibility-conferring genotype is -455G/A + AA.

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    Neurogenesis within the adult hippocampus under physiological conditions and in depression
    Martin Dokter, Oliver von Bohlen und Halbach
    2012, 7 (7):  552-559. 
    Abstract ( 469 )   PDF (222KB) ( 784 )   Save

    Adult neurogenesis can only be observed in some specific brain regions. One of these areas is the dentate gyrus of the hippocampal formation. The progenitor cells located in the subgranular layer of the dentate gyrus proliferate, differentiate, and give rise to young neurons that can become integrated into existing neuronal circuits. Under physiological conditions, hippocampal neurogenesis is linked to hippocampal-dependent learning, whereas deficits in adult hippocampal neurogenesis have been shown to correlate with disturbances in spatial learning and memory. This review summarizes the phenomenon of adult hippocampal neurogenesis and the use of suitable markers for the investigation of adult hippocampal neurogenesis. In addition, we focused on the disturbances in neurogenesis that can be seen in depression. Interestingly, several antidepressants have been found to be capable of increasing the rate of hippocampal neurogenesis. Based on that, it can be speculated that factors, which directly or indirectly increase the rate of hippocampal neurogenesis, may be helpful in the treatment of depression.

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