Objective To study the effects of light on body weight,learning and memory of mice.Methods Fifty mice aged 20 days were randomly assigned to one of the five groups: 200 W light group,100 W light group,60 W light group,40 W light group and normal control group,with 10 in each.They were exposed to different intensities of light 8 hours per day for 1 week.Then we monitored their body weight,examined the mean latency and inaccuracy number in step-down test,and examined the mean latency using a Morris' water maze to observe the effect of light pollution on the mice's learning and memory.Results Compared with the other four groups,there were significant decelerations of body weight increase in 200 W light group.No significant difference in body weight gain was found among the other four groups.The four light-treatment groups had no significant differences from control group in the mean latency,inaccuracy number in step-down test or the mean latency,or the mean crosses to the target in the Morris' water maze.Conclusion Short time high-intensity light can inhibit body weight increase in mice,but short-time light has no effect on the learning and memory of mice.

OBJECTIVE: To analyze the characteristics of medical malpractice from different grades of hospitals and to explore forensic investigation strategies in assessing medical dispute. METHODS: A total of 206 cases of medical dispute from 2009 to 2010 investigated by the Department of Forensic Medicine in Nanjing Medical University were selected and analyzed according to fault incidence, fault-prone part, and degree of causality in the treatment. RESULTS: Among the 206 cases analyzed, tertiary hospitals, secondary hospitals and primary hospitals showed medium, high and low error rate, respectively. A majority of medical malpractice cases were distributed in the departments of surgery, medicine and gynecology. CONCLUSION The frequency and severity of medical malpractice in primary hospitals were high, which were gradually reduced in tertiary and secondary hospitals.
Dissent and Disputes ; Expert Testimony ; Forensic Medicine ; Gynecology/statistics & numerical data* ; Hospital Departments/statistics & numerical data* ; Humans ; Incidence ; Malpractice/statistics & numerical data* ; Medical Errors/statistics & numerical data* ; Retrospective Studies ; Time Factors

Objective To demonstrate the relationship between Cdc20 mutation and the promotion of colon cancer via Cdc20loxp/+ APCmin/+ villin-cre+/-compound mutant mice.Methods Cdc20loxp/+ APCmin/+ villin-cre+/-compound mutant mice and APCmin/+ mutant mice were generated by mice mating strategy.The colon tumors of two group mice were compared by phenotypic analysis and histology analysis.Results Phenotypic analysis showed that the number of tumors in Cdc20loxp/+ APCmin/+ villin-cre+/-compound mutant mice group and APCmin/+ mutant mice group was 1.2±0.5 and 1.6±0.5, respectively (t =0.215, P =0.588), and the maximum diameter of tumors was (2.7±0.3) cm and (2.5±0.2) cm, respectively (t =0.568, P =0.575).Pathologic type of Cdc20loxp/+ APCmin/+ villin-cre+/-compound mutant mice was adenocarcinoma, while that of APCmin/+ mice was tubular adenoma.Conclusion Cdc20 carrying a null allele can accelerate the promotion of colon cancer in APCmin/+ mice without influence on the tumor number and size.

Objective To investigate the electrophysiological properties of layer Ⅱ/Ⅲ pyramidal neurons of the early postnatal stage rat visual cortex.Methods By using the whole cell patch-clamp recording technique combined with direct visualization of cells,we studied the passive and active electrophysiological properties as well as firing properties of layer Ⅱ/Ⅲ pyramidal neurons in acute rat visual cortical slices.Results Resting membrane potential,input resistance,membrane capacitance and membrane time constant of pyramidal neurons at postnatal days 11-13(P 11-13) were(-56.6?1.8)mV,(185.4?2.7)M?,(77.9?2.2)pF and(16.9?2.4)ms,respectively.Action potential amplitude and duration were(97.7?2.7)mV and(2.3?0.1)ms,respectively.Threshold potential was(-31.8?1.2)mV and afterdepolarizing potential was(-65.3?1.1)mV.When presented with long depolarizing current pulse of constant amplitude,most of the neurons exhibited pronounced adaptation of spike frequency.The steady-state firing frequency was(30.4?9.4)% of the first interval firing frequency.Conclusion The electrophysiological properties of layer Ⅱ/Ⅲ pyramidal neurons of the early postnatal stage rat visual cortex are not fully mature.Most of the neurons display regular firing patterns,but the degree of firing frequency adaptation is relatively small.

OBJECTIVE: To investigate function of glycine receptors (GlyRs) at the hippocampal CA1 pyramidal cells and to characterize the pharmacological properties of these receptors at early postnatal stage. METHODS: We used whole cell patch clamp recording to study the current response in the acutely prepared hippocampal slices from postnatal day 11-13 rats induced by glycine applied in the artificial cerebrospinal fluid. RESULTS: Application of glycine to the pyramidal cells elicited strychnine sensitive chloride currents. EC50 for GlyRs respond to glycine was 123. 23 μmol/L and Hill coefficient was 1.24. Picrotoxin could partly blocked the currents. CONCLUSION Strychnine sensitive glycine receptors are functionally expressed in CA1 pyramidal neurons in rat hippocampal CA1 area at early postnatal stage, and some of GlyRs are αβ heteromeric receptors.
Animals ; CA1 Region, Hippocampal ; cytology ; Glycine ; pharmacology ; Patch-Clamp Techniques ; Pyramidal Cells ; drug effects ; Rats ; Receptors, Glycine ; metabolism ; Strychnine ; pharmacology

RBC membrane shear elastic modulus and membrane viscosity are two important indexes reflecting RBC membrane viscoelasticity. Their variation was investigated in this study after rabbits were radiated with l60Co. With a new ektacytometer, we measured the small deformation index (DId) and the half-time of deformation relaxation (t0.5) of RBC in flow field then we calculated RBC membrane shear elastic modulus and membrane viscosity. We found that the value of RBC membrane shear elastic modulus and membrane viscosity continuously increased from 0 to 16th day then continuously decreased and tended to be stable on 60th day or so. The reason may lie in the variation of proportion of new and old RBC in blood and variation of microconformation of RBC membrane after rabbits were radiated with　60Co.

Objective To establish an acute yunaconitine poisoning rat model with a single oral administration and to determine the contents of yunaconitine in rat tissues by UPLC-MS/MS method, then investigate the distribution of yunaconitine in rats. Method The rats were randomly divided into three groups and were intragastrically administered a single dose of 2.2mg/kg,1.1mg/kg,0.7mg/kg yunaconitine, respectively.. The rats were killed 2h later, the stomach tissue, intestine tissue, liver tissue, pancreas tissue, kidney tissue, lung tissue, spleen tissue, heart tissue, bladder tissue, testis tissue, brain tissue and heart blood samples were collected. The contents of yunaconitine in the biological materials were determined by UPLC-MS/MS method after the biological samples extracted by liquid-liquid extraction. Result A rat model of the yunaconitine poisoning was made with a single dose of 1.1mg/kg, the concentrations of yunaconitine displayed in the organs with the following order:stomach, small intestine, liver, pancreas, kidney, lung, spleen, heart, bladder, testis, heart blood and brain. Conclusion Yunaconitine was widely distributed in rats, especially the levels in the stomach, small intestine and liver were the highest. The conclusion provides a basis for the selection of test materials for the poisoning of Aconitum vilmorinianum Kom.

Objective To assess the utility of single fiber EMG (SFEMG)in the differential diagnosis of hyperthyroidism associated with ocular myasthenia gravis (OMG)and Graves ophthalmopathy.Methods SFEMG was performed in orbicularis oculi muscle of 2 groups of patients.including 32 patients with hyperthyroidism associated with OMG,and 35 patients with Graves ophthalmopathy.The parameters of SFEMG between different groups were compared.Results The mean jitter was (96.2 ± 23.7),(42.8 ± 12.6)μs in hyperthyroidism associated with OMG and patients with Graves Orbitopathy. M50of the percentage of jitter ＞55 μs was 92% and 5% in the 2 groups respectively.M50of the percentage of block was 25% and 0 in the 2 groups respectively.Fiber density was (1.9 ± 0.4)and (1.7 ± 0.5)in the 2 groups respectively.There was significant difference in those parameters of SFEMG between the patients in 2 groups(t＝15.56,Z＝9.26,Z＝7.35,all P＜0.01).Conclusion SFEMG of orbicularis oculi muscle shows significantly increased jitter and block in hyperthyroidism associated with OMG,which can help to differentiate hyperthyroidism associated with OMG from Graves ophthalmopathy.

The self-renewal and multipotent potentials in neural stem cells (NSCs) maintain the normal physiological functions of central nervous system (CNS). The abnormal differentiation of NSCs would lead to CNS disorders. However, the mechanisms of how NSCs differentiate into astrocytes, oligodendrocytes (OLs) and neurons are still unclear, which is mainly due to the complexity of differentiation processes and the limitation of the cell separation method. In this study, we modeled the dynamics of neural cell interactions in a systemic approach by mining the high-throughput genomic and proteomic data, and identified 8615 genes that are involved in various biological processes and functions with significant changes during the differentiation processes. A total of 1559 genes are specifically expressed in neural cells, in which 242 genes are NSC specific, 215 are astrocyte specific, 551 are OL specific, and 563 are neuron specific. In addition, we proposed 57 transcriptional regulators specifically expressed in NSCs may play essential roles in the development courses. These findings provide more comprehensive analysis for better understanding the endogenous mechanisms of NSC fate determination.
Animals ; Astrocytes ; cytology ; metabolism ; Cell Differentiation ; genetics ; Gene Expression Profiling ; Gene Regulatory Networks ; Mice ; Neural Stem Cells ; cytology ; metabolism ; Oligodendroglia ; cytology ; metabolism ; Protein Interaction Mapping

Late-phase long-term potentiation (L-LTP) plays a very important role in the maintenance of long-term memory in hippocampus. However, studies have shown that L-LTP can be reversed by subsequent neuronal activity. The aim of the present study is to investigate whether the presynaptic mechanism and the change of AMPARs expressions are involved in the reversal of L-LTP in hippocampal CA1 area. Standard extracellular recording technique was used to record the potential change in the stratum radiatum of CA1 area of adult rat hippocampal slices. Two hours after LTP induction, which was induced by high-frequency stimulation (HFS), two episodes of high-intensity paired-pulse low-frequency stimulation (HI-PP-LFS) were delivered to induce L-LTP reversal. Paired-pulse ratios (PPR) were obtained before LTP induction, 2 h after LTP induction and 30 min after LTP reversal. On the other hand, immunofluorescence histochemistry was used to detect AMPARs expressions before and after L-LTP reversal. The results showed that, after 2 h of induction, L-LTP was partially reversed by two episodes of HI-PP-LFS, and the percentage of depotentiation was 61.79%+/-14.51%. PPR obtained before and after LTP induction, and as well that after LTP reversal, are all more than 1, showing paired-pulse facilitation (PPF). Multiple comparison indicated PPR before LTP induction was the greatest one, and PPR after LTP induction was the smallest. In addition, no significant difference was observed in the intensity of AMPAR/GluR2 immunoreactivity in CA1 area among control group, LTP group and LTP reversal group. These results suggest that the presynaptic mechanism is involved in both the maintenance and reversal of L-LTP and there is no change in AMPAR/GluR2 expression before and after the reversal of L-LTP.
Animals ; CA1 Region, Hippocampal ; metabolism ; physiology ; Electric Stimulation ; Long-Term Potentiation ; physiology ; Male ; Presynaptic Terminals ; physiology ; Rats ; Rats, Sprague-Dawley ; Receptors, AMPA ; metabolism