let-7e is one member of let-7 miRNA family, a class of endogenous noncoding RNA which consists of 22 nucleotides. The recent miRNA profiles investigation and analysis results showed that let-7e could be involved in embryonic stem cells differentiation, tumorigenesis in cancer, temporal lobe epilepsy and sleep loss, lipopolysaccharide induced inflammation by regulating its target mRNA expression. This paper gives a review of the important biological function of let-7e.

Epilepsy is one of the nervous system diseases,which is correlated with multiple pathogenic factors and caused by repeated discharge of neurons.Currently,there are more than 50 million people worldwide suffering from epilepsy with an average annual increase of 100 000 cases.The prevalence rate of sleep disorders in epilepsy patients is high,by up to two times than that of healthy subjects.Common sleep disorders in epilepsy patients include insomnia,sleep apnea,restless legs syndrome and parasomnias.The characteristics of sleep abnormalities have differences with the epilepsy syndromes.The relationship between epilepsy and sleep is complex and interactive.The mechanism of combined sleep disorders in epilepsy patients is still unclear.In this paper,the relationship between epilepsy and sleep disorders in epilepsy patients was summarized,which involves multiple aspects such as the possible mechanism of combined sleep disorders,the common features of sleep disorders,the possible mechanism of sleep abnormalities in different epilepsy syndromes and the characteristics of sleep structure,the effect of antiepileptic drugs on sleep architecture abnormalities and its role in combined sleep disorders.

Objective To investigate the characteristic of sleep disorders in patients with frontal lobe epilepsy (FLE) through polysomnography and subjective questionnaires. Methods Eighteen FLE patients (FLE group) and 15 healthy subjects (control group) were recruited to our study. Two groups were evaluated by whole-night polysomnography, included total time in bed (TIB), total sleep time (TST), sleep efficiency (SE), sleep latency (SL), rapid eye movement (REM) latency (RL), wake after sleep onset (WASO), the percentage of non-REM (NREM) 1, 2, 3 stages and the percentage of REM occupied TST, the apnea-hypopnea index (AHI), hypopnea index, mean oxygen saturation (SpO2) and nadir oxygen saturation, periodic leg movements (PLMs) index and PLMs index of REM sleep, sleep stage shifts (SSS) and sleep stage shifts per hour (SSS/h), wake, NREM1, NREM2, NREM3 and REM sleep stage shifts (abbreviated as N1, N2, N3, REM, W) and their proportions of SSS (abbreviated as N1/SSS, N2/SSS, N3/SSS, REM/SSS, W/SSS). Data of depress and fatigue degrees, sleep quality, excessive daytime sleepiness were assessed by subjective questionnaires. Results Compared with control group, TIB [(503.22±62.33) min], WASO[(54.11±18.97) min], SSS (161.17±56.83), SSS/h (22.60±6.25), N1(42.56± 15.26) and N2 (57.28 ± 26.57), number of wake stage (25.33 ± 10.97) were significantly increased in FLE group. Meanwhile, scores of depression (9.33±5.01) and fatigue (5.72±3.36) were increased in FLE group compared with those of control group. Conclusion The sleep disorders can be found in FLE, which are related with depression and FLE seizure frequency.

The medulla oblongata is located at the lower end of the brain stem, and it has abundant blood supply. The incidence of medial medullary infarction is low in cerebrovascular diseases. Bilateral medial medullary infarction is even rare. Bilateral medial medullary infarction is mainly characterized by paralysis. The respiratory failure can occur in severe cases. Magnetic resonance diffusion imaging can present aheartorYshaped lesion. We treated 1 patient with a typicalYshaped bilateral medial medullary infarction.

Objective To explore the effects of repetitive transcranial magnetic stimulation (rTMS) on hippocampus metabolic changes in rats with temporal lobe epilepsy. Methods A chronic temporal lobe epilepsy model was established by use of lithium-pilocarpine in rats. The hippocampus metabolism of the rats were detected by 1H-MRS method before and after the rTMS and compared with that of the normal controls. Relative ratios of N-acetylaspartate (NAA), choline (Cho), glutamate (Glu) and ?-aminobutyric acid (GABA) over creatine (Cr) were calculated. Results Compared with normal control rats, NAA/Cr and GABA/Cr ratios decreased significantly and Cho/Cr ratios increased significantly in hippocampus of the rats with temporal lobe epilepsy. After rTMS NAA/Cr and GABA/Cr ratios increased significantly and Cho/Cr ratios decreased significantly in hippocampus of rats with temporal lobe epilepsy. However, rTMS did not significantly affect the Glu/Cr ratio in hippocampus of the rats with temporal lobe epilepsy. Conclusion rTMS could improve the hippocampus metabolism and exert a neuroprotective effect against brain damage induced by epilepsy.

Long-term potentiation(LTP)is an important form of synaptic plasticity and an objective indicator to investigate learing and memory synaptic mechanisms.With the development of brain slice technology,more and more experiments associated with LTP are carried out on brain slices,which aim to investigate the mechanism in biology and the change in physiology or biochemistry are carried out on the brain slice.This paper gives an overview of recent advances in research of LTP with technology of brain sliceby suchexamples as follows:The regulated expression mechanisms of long-term potentiation at CA1 synapses,the characteristics of LTP induced in hippcampal slices and its relation with the slice-recovery conditions,the enhancement of the magnitude of early longterm potentiation at CA1 hippocampal synapse by the activation of dopamine receptor,and the enhancement of associative long-term potentiation by the activation of β-adrenergic receptors at CA1 synapses in rat hippocampol slices.

Objective To investigate the characteristic of theta oscillation in patients with frontal lobe epilepsy (FLE) by the analysis of multi-channel electroencephalographs (EEGs) during rest state and working memory(WM) maintenance. Methods The 19 FLE patients and 17 healthy subjects underwent EEG recording with 34-channel EEG machine during visual working memory task performance. The differences of behavioral results were analyzed between FLE group and controls. Short-time Fourier transform was used to calculate the power spectral density of different frequency bands in 34 channels. The theta power values during the retention period of working memory and rest state were compared between two groups. Results Compared with controls, reaction time of FLE increased significantly (P<0.01) and accuracy decreased (P<0.05). The power spectral density of theta band for FLE increased both in Fz and frontal region during rest state (P<0.01). Compared with controls, the power spectral density of theta oscillation decreased significantly in the frontal region for FLE during WM maintenance. Conclusion Our results suggest that working memory in patients with FLE was impaired. The absence of theta oscillation during the WM delayde period may provide a possible neural mechanism for the working memory dysfunction in FLE.

Objective To study the regulating roles of PAI 2 in the differentiation mechanism of the human epidermis. Methods Human skins were take from the early, middle and late human embryos respectively and observed with immunocytochemistry and in situ hybridization techniques. The cell culture and dot blot were also used in the observation of the materials from late embryo. Results 1 PAI 2 exhibits a very high experssion in the development of embryonic period, with the highest level in the middle embryonic phase while the transcripts of PAI 2 still keep a rather high level in the late human embryonic stage. 2 PAI 2 is mainly localized in the superficial, more differentiatied layers of the epidermis.3 PAI 2 is localizated in peripheral cytoplasm of the vitro or vivo keratinocyte.Conclusion PAI 2 is involved in the regulation of the keratinocyte differentiation. [

OBJECTIVE:To study the contents changes of polysaccharide and 5-HMF in Polygonati rhizoma from different pro-ducing areas after different processing,and provide reference for the development of processing technology of Polygonati rhizoma from different producing areas and the quality standard of different processing products. METHODS:UV spectrophotometry and HPLC were conducted to respectively determine the contents of polysaccharide and 5-HMF,and compare the content differences of polysaccharide and 5-HMF in Polygonati rhizoma from different producing areas [Shaanxi Lueyang County,Shaanxi Huangling County,Yunnan Fumin County (genuine producing areas),Shaanxi Taibai County] by fresh-cutting,dry-cutting,steaming and steaming with wine. RESULTS:Polysaccharide of sample from Yunnan Fumin County showed the highest content in fresh-cut sam-ples(13.4%),no 5-HMF(0)was detected;polysaccharide contents were respectively 10.8%-13.4%,8.9%-10.8%,5.5%-6.9%, 5.6%-6.5% after fresh-cut,dry-cut,steamed and steamed with wine,5-HMF contents were 0,0,0.21%-0.50%,0.25%-0.72%. Compared with no processing samples (fresh-cut),polysaccharide contents in Polygonati rhizoma were decreased in turn after dry-cut,steamed and steamed with wine,5-HMF contents were increased in turn after steamed and steamed with wine. CONCLU-SIONS:It is suggested to consider origin factor in developing processing technology of Polygonati rhizoma from genuine and non-genuine producing areas. 5-HMF content determination index should be added into quality standard of processing products after steamed and steamed with wine.

Objective To evaluate the predictors of maternal and fetal outcome of pregnancy for systemic lupus erythematosus(SLE)patients.MethodsNinety-four patients with 96 pregnancies which were evaluated retrospectively from Jan 1990 to Jan 2008 in Peking Union Medicai College Hospital were divided into two groups:disease stable during pregnancy(group A)and lupus flares during pregnancy (group B).Statistical analysis was performed by X2 or Fisher exact test and Student's t-test.A binary logistic regression model was used to evaluate the predictors of matemal and fetal outcome.Results There were 36 pregnancies with stable lupus disease(group A)and 60 pregnancies with lupus flares(group B).of the 96 pregnancies.18 resulted in therapeutic abortion and 7 in fetal loss,71 resulted in a live birth,3 in neonatal death.The rates of preterm delivery,small gestational age(SGA)and neonatal asphyxia in group B were higher than those in group A(P＜0.05).By binary logistic regression analysis,preeclampsia/eclampsia low serum platelet count and SLE flares were associated with poor fetal outcome(β=2.463,2.228.2.769 respectively.P＜0.05).,rhere were 56 pregnancies with stable lupus disease at the conception with 22(39.3%)occurred lupus flares during pregnancies.Twenty-four preeclampsia and 2 eclampsia were seen in all the pregnancies.Fifty-two pregnancies were complicated with lupus nephritis,and 25 pregnancies(48.1%,25/52)of which were disease stable at the conception,and among 22 pregnancies with disease stable over one year.twelve of which occurred lupus nephritis flares.Three pregnancies which have disease activity within one year before pregnancy all occurred lupus nephritis flares.There were four maternal death which all occurred at the postpartum.By binary logistic regression analysis,lupus nephritis flares were associated with preeclampsia/eclampsia(B=2.658,P＜0.05),and proteinuria at the conception before dilivery were significantly associated with SLE flares(13=3.263,P＜0.05).Conclusion An increase of fetal loss,preterm delivery,SGA and neonatal asphyxia was seen in patients with lupus flares during pregnancy compared with those with stable disease.About 1/3 lupus activity may increase after pregnancy.Preeclampsia and eclampsia were increased when there were lupus nephritis flares.