Correlation between level of serum prolactin and epileptic discharges of electroencephalogram from 24 to 36 hours after epileptic onset

BACKGROUND： Researchers discovered that serum prolactin could rise following an epileptic seizure. The prolactin level might reach three times more than basic level within 30 minutes and decrease to the normal value 2 hours after the seizure occurred. The mechanism might result in an increase of serum prolactin concentrations with the activation of the hypothalamic-pituitary axis. OBJECTIVE：To probe into the correlation between changes of serum prolactin and incidence of epileptic discharges of electroencephalogram （EEG） at 24-36 hours after epileptic onset of patients with secondary epilepsy. DESIGN ： Clinical observational study SEI-FING： Department of Neurology, First Hospital affiliated to Soochow University PARTICIPANTS： A total of 21 patients with secondary epilepsy were selected from the Department of Neurological Emergency or Hospital Room of the First Hospital affiliated to Soochow University from November 2005 to April 2006. There were 14 males and 7 females aged from 25 to 72 years. All patients met International League Anti-epileptic （ILAE） criteria in 1981 for secondary generalized tonic clonic seizure through CT or MRI and previous EEG. All patients were consent. Primary diseases included cerebral trauma （3 cases）, tumor （2 cases）, stroke （7 cases） and intracranial infeion （9 cases）. METHODS ： Venous blood of all patients was collected at 24-36 hours after epileptic onset. Serum prolactin kit （Beckman Coulter, Inc in USA） was used to measure value of serum prolactin according to kit instruction. Then, value of serum prolactin was compared with the normal value （male： 2.64-13.13 mg/L; female： 3.34- 26.72 mg/L）; meanwhile, EEG equipment （American Nicolet Incorporation） was used in this study. MAIN OUTCOME MEASURES ： ① Abnormal rate of serum prolactin of patients with secondary epilepsy; ②Comparison between normal and abnormal level of serum prolactin and incidence of EEG epileptic discharge of patients with secondary epilepsy. RESULTS：All 21 patients with secondary epilepsy were involved in the final analysis. ① Results of serum prolactin level： Among 21 patients with of secondary epilepsy, 10 of them had normal serum prolactin and 11 had abnormal one, and the abnormal rate was 52% （11/21）. ② Detecting results of EEG： EEG results showed that 6 cases were normal and 15 were abnormal, and the abnormal rate was 71% （15/21）. The symptoms were sharp wave, spike wave or sharp slow wave, spike slow wave of epileptic discharges in 8 cases, which was accounted for 38%. ③ Correlation between abnormality of serum prolactin and EEG epileptic wave： Eleven cases had abnormal serum prolactin, and the incidence was 64% （7/11）, which was higher of epileptic wave than that of non-epileptic wave [36% （4/11）, P 〈 0.05]; however, 10 cases had normal serum prolactin, and the incidence was 10% （1/10）. Epileptic wave was lower than non-epileptic wave [90% （9/10）, P 〈 0.01]. CONCLUSION ： The level of serum prolactin of patients with secondary epilepsy is abnormally increased at 24- 36 hours after epileptic onset; in addition, incidence of epileptic discharge is also increased remarkably.

Noise level estimation method with application to EMD-based signal denoising

This paper proposes a new signal noise level estimation approach by local regions. The estimated noise variance is applied as the threshold for an improved empirical mode decomposition（EMD） based signal denoising method. The proposed estimation method can effectively extract the candidate regions for the noise level estimation by measuring the correlation coefficient between noisy signal and a Gaussian filtered signal. For the improved EMD based method, the situation of decomposed intrinsic mode function（IMFs） which contains noise and signal simultaneously are taken into account. Experimental results from two simulated signals and an X-ray pulsar signal demonstrate that the proposed method can achieve better performance than the conventional EMD and wavelet transform（WT） based denoising methods.

Analysis of the relationship between water level fluctuation and seismicity in the Three Gorges Reservoir(China)

The Three Gorges Reservoir is a good site for the further researches on reservoir induced seismicity due to decades＇ seismic monitoring. After the first water impounding in 2003, seismic activity becomes more frequent than that before water impoundment. In order to quantitatively study, the relationship between the water level fluctuation and earthquakes in TGR, we introduced statistical methods to attain the goal. First of all, we relocated the earthquakes in TGR region with double difference method and divided the earthquakes into 5 clusters with clustering analysis method. Secondly, to examine the impacts of water level fluctuation in different water filling stages on the seismic activity in the 5 clusters, a series of statistical analyses are applied. Pearson correlation results show that only the 175 m water level fluc- tuation has significantly positive impacts on the seismic activity in clusters I, II, III and V with correlation coefficients of 0.44, 0.38, 0.66 and 0.63. Cross-correlation analysis demonstrates that 0, ], 0 and 0 month time delay separately for the clusters I, II, III and V exists. It illustrated the influences of the water loading and pore pressure diffusion on induced earthquakes. Cointegration tests and impulse response analysis denoted that the 175 m water level only had long term and significant effects just on the seismic events in the intersection region of the Fairy Mount Fault and Nine-brook Fault. One standard deviation shock to 175 m water level increased the seismic activity in cluster V for the first 3 months, and then the negative influence was shown. After 7 months, the negative impulse response becomes stable. The long-term effect of the 175 m water impoundment also proved the important role of pore pressure diffusion in RIS with time.

Relationship between lipidslevelsand right ventricular volume overload in congestive heart failure

BackgroundThe relationship between lipids and coronary artery disease has been well established. However, this is not the case between lipids and heart failure. Ironically, high lipid levels are associated with better outcomes in heart failure, but the mechan-isms underlying the phenomenon are not fully understood. This study was performed to test the hypothesis that reduced intestinal lipid absorption due to venous congestion may lead to low lipid levels.MethodsWe collected data of clinical characteristics, echocardio-graph, and lipid profile in 442 unselected patients with congestive heart failure. Correlations between lipid levels[including total cho-lesterol（TCL）, high-density lipoprotein cholesterol（HDL-C）, low-density lipoprotein cholesterol（LDL-C）, and triglycerides（TG）]and right ventricle end diastolic diameter （RVEDD）, left ventricle end diastolic diameter （LVEDD）, right atrium diameter （RA）, left atrium diameter （LA）, or left ventricle ejection fraction （LVEF） were analyzed using Pearson correlation and partial correlation. RVEDD, LVEDD, RA, and LA were indexed to the body surface area.ResultsThere was a significantly inverse correlation between TCL le-vels and RVEDD （r=-0.34,P〈0.001） and RA （r=-0.36,P〈0.001）. Other lipids such as LDL-C, HDL-C, and TG had asimilar inverse correlation with RVEDD and RA. All these correlations remained unchanged after adjusting for age, gender, smoking status, physical activity levels, comorbidities, and medication use.ConclusionsLipid levels were inversely correlated to RVEDD in patients with congestive heart failure; however, because this was an observational study, further investigation is needed to verify our results as wellas identify a causal relationship, if any.

Natural variation of hormone levels in Arabidopsis roots and correlations with complex root architecture

Studies on natural variation are an important tool to unravel the genetic basis of quantitative traits in plants. Despite the significant roles of phytohormones in plant development, including root architecture, hardly any studies have been done to investigate natural variation in endogenous hormone levels in plants. Therefore, in the present study a range of hormones were quantified in root extracts of thirteen Arabidopsis thaliana accessions using a ultra performance liquid chromatography triple quadrupole mass spectrometer. Root system architecture of the set of accessions was quantified, using a new parameter （mature root unit） for complex root systems, and correlated with the phytohormone data. Significant variations in phytohormone levels among the accessions were detected, but were remarkably small, namely less than three-fold difference between extremes. For cytokinins, relatively larger variations were found for ribosides and glucosides, as compared to the free bases. For root phenotyping, length-related traits--lateral root length and total root length--showed larger variations than lateral root number-related ones. For root architecture, antagonistic interactions between hormones, for example, indole-3-acetic acid to trans-zeatin were detected in correlation analysis. These findings provide conclusive evidence for the presence of natural variation in phytohormone levels in Arabidopsis roots, suggesting that quantitative genetic analyses are feasible.

The correlation between serum uric acid level and early- phase insulin secretion in subjects with normal glucose regulation

Objective To investigate the correlation between serum uric acid(SUA)level and early-phase insulin secretion in subjects with normal glucose regulation(NGR).Methods Totally 367 community NGR residents confirmed by a 75g oral glucose tolerance test were enrolled.