In order to explore if mature neurons derived from neural stem cells have the potentiality to divide, we utilized the chemical digestion method to disperse the adult rat brain tissue into single cells, and culture them in serum-free medium. After being cultured for about eight days in vitro, the neural stem cells were induced to differentiate into neurons. The neurons were further induced to divide. Utilizing the method of serial photograph and NF-160 immunocytochemistry, the processes of division of some neurons were recorded. At the same time, PCNA+NF-160 (or Chat, GABA, GAD) double label were used to investigate if the dividing-neurons were mature ones. After the neural stem cells were induced to differentiate in vitro for eight days, they possessed the shape and character of mature neurons. The differentiated neuron had a big nucleus and one or two distinct nucleolus in the nuclear. Within the perikaryon,there were a large amount of dense and Nissl body-like structure. Several long processes emerged from various locations of the cell body. Then, EGF and bFGF were added into the medium to induce division. After two days of induced-division, neuron-like cells were observed to divide; moreover, the number of neuron-like cells in the region increased continually. Immunocytochemistry demonstrated these cells were NF-160-positive. Serial photographs of dividing-process of neuron-like cells were obtained and their daughter cells were also NF-160-positive. After PCNA+NF-160 (or Chat, GABA, GAD) double label, some cells showed brown cell plasma and black nucleus. The above-mentioned results indicate that neurons, which were previously thought to be end-differentiated, can be re-called into cell cycle under appropriate conditions. Mature neurons still have the potential to divide, proliferate and self-renew.
Animals ; Brain ; cytology ; Cell Differentiation ; Cell Division ; Cell Separation ; Cells, Cultured ; Epidermal Growth Factor ; pharmacology ; Fibroblast Growth Factor 2 ; pharmacology ; Neurons ; cytology ; Photography ; methods ; Proliferating Cell Nuclear Antigen ; pharmacology ; Rats ; Rats, Wistar ; Stem Cells ; cytology

Objective:To compare the two-dimensional electrophoresis(2-DE) maps of rat spinal cord protein extracted by two different solution systems.Methods: Adult rat spinal cord protein was precipitated with 10% trichloracetic acid in acetone and resuspended in 8 mol/L urea plus 4%CHAPS (A solution) or, 5 mol/L urea, 2 mol/L thiourea, 2%CHAPS plus 2%SB3-10 (B solution). One hundred and fifty micrograms of protein was loaded on 18 cm IPG strip holder and run isoelectric focusing electrophoresis as the first dimension, then horizontal SDS-PAGE as the second dimension. Protein spots were visualized by silver stain.Results:There were 1 059 and 1 023 protein spots in each map, of which 790 spots were matched in two maps. There were 269 and 233 spots exclusively extracted by A and B solutions, respectively. Taken together, 1292 different spots were totally obtained by A and B solutions.Conclusion: Integrating protein spots extracted by different solution systems is beneficial for achieving intact 2-DE map of tissues.

The purpose of this investigation was to re-evaluate the neurotrophic effect of GPI-1046 on neurite outgrowth in vitro. GPI-1046 was synthesized and identified with mass spectrometry, nuclear magnetic resonance and elemental analysis. Chicken dorsal root ganglions (DRGs) were removed and divided into three groups: (1) The DRGs were cultured in DMEM containing different concentrations of GPI-1046; (2) The DRGs were cultured in DMEM containing nerve growth factor (NGF) alone at 0.8 and 8 ng/mL, respectively; (3) The DRGs were cultured in DMEM containing both different concentrations of GPI-1046 and NGF at 0.8 ng/mL. The results showed that GPI-1046 alone could not stimulate chicken DRG neurite outgrowth; however, GPI-1046 stimulated DRG neurite outgrowth only in the presence of NGF at low concentration in the culture medium.
Animals ; Cells, Cultured ; Chickens ; Ganglia, Spinal ; drug effects ; growth & development ; Nerve Growth Factor ; pharmacology ; Neurites ; drug effects ; Pyrrolidines ; pharmacology

The acute traumatic spinal cord injury (SCI) is a commonly seen and severe case in clinic. However, the repair and regeneration of injured spinal cord is limited. This is likely due to that different kinds of factors are involved in regeneration after SCI. In the present study, we used complementary DNA microarray consisting of 4 041 specific probes from rat to identify genes that were differentially expressed after SCI. The animals were subjected to complete transection injury of the thoracic spinal cord (T8-T9). Sham operated animals received only a laminectomy. Four and a half days later, rat spinal cord was dissected out for total RNA isolation. The fluorescent (Cy3 and Cy5) labeled probes were prepared and hybridized to the microarray. Genes that showed 2-fold difference in SCI tissue were identified. Sixty-five up-regulated genes consisted of 21 known genes, 30 known expressed sequence tags (ESTs) and 14 unknown genes. Seventy-nine down-regulated genes comprised 20 known genes, 42 known ESTs and 17 unknown genes. In 41 differentially expressed known genes, 5 up-regulated genes, i.e., tissue inhibitor of metalloproteinase 1 (Timp1), transgelin (Tagln), vimentin (Vim), Fc gamma receptor, cathepsin S (Ctss), and 3 down-regulated genes, i.e., stearyl-CoA desaturase, coagulation factor II (F2), endosulfin alpha (Ensa), were further confirmed by reverse transcription polymerase chain reaction (RT-PCR). These genes may play a role in the response to tissue damage or repair following SCI and characterization of them might be helpful to elucidate the molecular mechanisms of spinal cord injury and regeneration.
Animals ; Expressed Sequence Tags ; Gene Expression Profiling ; Gene Expression Regulation ; Male ; Nerve Tissue Proteins ; genetics ; Oligonucleotide Array Sequence Analysis ; Random Allocation ; Rats ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction ; Spinal Cord Injuries ; genetics ; physiopathology ; Spinal Cord Regeneration ; genetics

BACKGROUND: Delivery room resuscitation assists preterm infants, especially extremely preterm infants (EPI) and extremely low birth weight infants (ELBWI), in breathing support, while it potentially exerts a negative impact on the lungs and outcomes of preterm infants. This study aimed to assess delivery room resuscitation and discharge outcomes of EPI and ELBWI in China. METHODS: The clinical data of EPI (gestational age [GA] <28 weeks) and ELBWI (birth weight [BW] <1000 g), admitted within 72 h of birth in 33 neonatal intensive care units from five provinces and cities in North China between 2017 and 2018, were analyzed. The primary outcomes were delivery room resuscitation and risk factors for delivery room intubation (DRI). The secondary outcomes were survival rates, incidence of bronchopulmonary dysplasia (BPD), and risk factors for BPD. RESULTS: A cohort of 952 preterm infants were enrolled. The incidence of DRI, chest compressions, and administration of epinephrine was 55.9% (532/952), 12.5% (119/952), and 7.0% (67/952), respectively. Multivariate analysis revealed that the risk factors for DRI were GA <28 weeks (odds ratio [OR], 3.147; 95% confidence interval [CI], 2.082-4.755), BW <1000 g (OR, 2.240; 95% CI, 1.606-3.125), and antepartum infection (OR, 1.429; 95% CI, 1.044-1.956). The survival rate was 65.9% (627/952) and was dependent on GA. The rate of BPD was 29.3% (181/627). Multivariate analysis showed that the risk factors for BPD were male (OR, 1.603; 95% CI, 1.061-2.424), DRI (OR, 2.094; 95% CI, 1.328-3.303), respiratory distress syndrome exposed to ≥2 doses of pulmonary surfactants (PS; OR, 2.700; 95% CI, 1.679-4.343), and mechanical ventilation ≥7 days (OR, 4.358; 95% CI, 2.777-6.837). However, a larger BW (OR, 0.998; 95% CI, 0.996-0.999), antenatal steroid (OR, 0.577; 95% CI, 0.379-0.880), and PS use in the delivery room (OR, 0.273; 95% CI, 0.160-0.467) were preventive factors for BPD (all P < 0.05). CONCLUSION Improving delivery room resuscitation and management of respiratory complications are imperative during early management of the health of EPI and ELBWI.
Birth Weight ; Bronchopulmonary Dysplasia ; China/epidemiology* ; Delivery Rooms ; Female ; Gestational Age ; Humans ; Infant ; Infant, Extremely Low Birth Weight ; Infant, Extremely Premature ; Infant, Newborn ; Male ; Pregnancy