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To improve the accuracy of Direction Of Arrival (DOA) estimation in Multiple Input Multiple Output (MIMO) radar systems under unknown mutual coupling, we propose a mutual coupling calibration and DOA estimation algorithm based on Sparse Learning via Iterative Minimization (SLIM). The proposed algorithm utilizes the spatial sparsity of target signals and estimates the spatial pseudo-spectra and the mutual coupling matrices of MIMO arrays through cyclic optimization. Moreover, it is hyperparameter-free and guarantees convergence. Numerical examples demonstrate that for MIMO radar systems under unknown mutual coupling conditions, the proposed algorithm can accurately estimate the DOA of targets with small angle separations and relatively high Signal-to-Noise Ratios (SNRs), even with a limited number of samples. In addition, low DOA estimation errors are achieved for targets with large angle separations and small sample sizes, even under low-SNR conditions.

The fermentation process of traditional Baijiu Daqu involves extremely complex changes in microbial communities, and the microbial communities work collaboratively to determine the quality of Daqu. Analyzing the composition and functions of microbial community during Daqu fermentation is the key to revealing its fermentation mechanism, putting forward a rational control strategy and stabilizing the quality of Daqu. Therefore, microbial communities and functions have always been the focus of Daqu research. In this paper, the characteristics of microbial community structure in different types of Baijiu Daqu are summarized. The microbial sources involved in Daqu fermentation, the succession of microbial community and its driving factors, and the changes of microbial community during the storage period of Daqu are reviewed. The functions of microorganisms involved in Daqu fermentation are summarized. Finally, future research prospects are discussed. This review is expected to provide a reference for further research on the fermentation mechanism of Daqu.

ObjectivesDomain adaptive technology is widely used in the bearing fault diagnosis of variable operating conditions. However, most domain adaptive technology only focuses on the global domain distribution and ignores the subdomain distribution, and the domain-invariant feature quality is easily affected by noise, leading to a significant decrease in diagnostic accuracy under varying operation conditions. Therefore, a fault diagnosis method based on a self-attention subdomain adaptive adversarial network (SASAAN) is proposed.MethodsFirst, a convolutional block attention module (CBAM) is utilized to extract the fault-related domain-invariant features in the vibration signals of the source and target domains. The adversarial network and subdomain adaptive module are then combined to reduce differences in the global and local domain edge distributions of different operating condition data, thereby improving the transferability of the data. The loss function is optimized by back propagation using the Adam optimizer to improve the diagnostic performance of the model, and the hyperparameter tuning of the model is also performed. Finally，the diagnostic results on the target domain test set are output by the failure classifier, and the Ottawa bearing data set is used to validate the effectiveness of the proposed method. ,ResultsThe results show that the fault diagnosis accuracy of the proposed method is higher than 96% under the condition of strong noise and varying operation conditions, which is obviously better than other methods.ConclusionThe results of this study can provide valuable references for the fault diagnosis of rolling bearings under varying operation conditions.

ObjectiveIn order to provide a quantitative basis for the layout of buoyant material in a submersible to improve its initial transverse metacentric height, this paper attempts to obtain the critical height equation of buoyant material through analytic derivation, and proposes layout schemes and suggestions on this basis.MethodsBy deriving the initial transverse metacentric height equation after adding buoyant material in combination with the partial derivatives method, such factors as buoyant material volume and gravity center are analyzed, and the buoyant material critical height equation is obtained through equivalent substitution. To gain a better understanding of the critical height equation and other factors that can affect the results such as displacement and transverse metacentric height before the installation of the buoyant material, an equivalent mathematical model of a typical transverse section of a submersible is constructed, and different numerical examples are studied by comparison.ResultsIt is concluded that the initial transverse metacentric height of a superior scheme can be 1.8% higher compared to pre-installation conditions. It is also likely that much better initial transverse metacentric height could be achieved if the 3D districts were released.ConclusionsThe results of this study can improve the initial transverse metacentric height of submersibles. The proposed equation is key to a buoyant material layout scheme. In addition, several layout principles are put forward to help designers when incorporating buoyant material into submersible design.

To prevent the degradation of the detection performance of Dual-Function Radar-Communication (DFRC) system in the presence of clutter, we propose the joint design of a transmit waveform and receiver filter to suppress the clutter and enhance the target detection performance. We use the Signal-to-Interference-plus-Noise Ratio (SINR) as the design criterion. Meanwhile, the Multi-User Interference (MUI) energy of the communication signals is constrained to maintain the quality of service for information transmission via DFRC systems. In addition, a similarity constraint is enforced to enable the transmitted waveform to have a good ambiguity function. To tackle the joint optimization problem, we present an iterative algorithm based on cyclic optimization and Semi-Definite Relaxation (SDR). The convergence of the algorithm is proved by a theoretical analysis. The simulation results show that the designed waveform can improve the target detection performance of a DFRC system in clutter and efficiently realize multi-user communication.

Objectives Typically, the fixed kentledge laying scheme of a submersible requires a significant amount of work and can often produce unpleasant results in engineering practice. Intelligent algorithms are considered for application in order to optimize the scheme. This paper proposes a genetic algorithm based method to solve the problem. MethodsFirst, by studying typical transverse sections of kentledge laying in a submersible and reverse-thinking the finite element method, a simplified equivalent mathematic model is constructed. Next, constraint functions and objective functions are extracted from the model. By using a genetic algorithm, improved fixed kentledge laying schemes are acquired with lower centers of gravity. By computing different examples, this method is proven to be effective in gaining good gravity center results with a much smaller workload.ResultsThe result shows that the gravity center of the improved scheme can be 23% lower compared to the ordinary scheme. This method is also effective in balancing longitudinal moment and lateral moment at the same time. ConclusionsThis study shows that the equivalent mathematical model and optimization method are feasible, and can improve both work efficiency and gravity results. Several general principles are also concluded, which can be helpful in engineering practice.

ObjectivesSubmarine construction is a multi-procedural coupled process. With the development of modular construction mode, its "outfitting" in a broad sense includes the whole process of material forming, structure building, equipment piping system manufacturing, installation and painting, in the design phase, precisely allocated top-level submarine outfitting plan can effectively influence the submarine construction process and ensure the overall functional performance.MethodsWith a focus on submarine outfitting between pressure and non-pressure hulls, the precision allocation process is suggested, the connotations and scope of the application of the precision allocation method based on the dimensional chain are discussed, and finally the key elements between pressure and non-pressure hulls and their precision control objects are identified according to the dimensional chain principle, and any unknown precision items throughout the outfitting process are allocated.ResultsThe allocation value of unknown precision items in the list of key outfitting items is obtained to meet construction precision requirements.Conclusions A precision allocation process and method, including materials, structures, equipment, and installation, is formed, which can be used to guide the processes and process designs of submarine outfitting.

Objective To determine the effect of serum bilirubin level on the parameters of quantitative electroencephalogram (qEEG) in neonates and investigate their correlation. Methods Clinical data of the neonatal infants (with a gestational age of 35~42 weeks) admitted to the Department of Neonatology, the Third Xiangya Hospital from January to December 2019 were collected and analyzed. According to the serum level of total serum bilirubin (TSB) in 24 h before qEEG, the children were divided into group A (< 221 μmol/L), group B (221 ~342 μmol/L) and group C (≥342 μmol/L). The changes in qEEG parameters were compared among the 3 groups, and the correlation of the TSB level with the qEEG parameters were analyzed. Results There were 104 neonatal infants enrolled, including 56 in group A, 24 in group B, and 24 in group C. In the frontal region, there were no statistical differences in the total spectral power, spectral edge frequency (SEF), absolute power of frequency bands and relative power of frequency bands in the 3 groups. But the total spectral power in group C was significantly higher than that in the other 2 groups (P < 0.05). In the temporal region and occipital region, SEF differed significantly among the 3 groups (P < 0.05), and the SEF in group C was significantly lower than that in the other 2 groups (P < 0.05). SEFs were negatively correlated with TSB in the frontal region, temporal region, and occipital region (P < 0.05). Conclusion In neonates, serum TSB level is correlated with SEF of qEEG, SEF might become an important indicator to monitor the effect of neonatal hyperbilirubinemia on brain function.

Microwave heating was used in this study to chlorinate the extraction of Fe, Mn, V, and Cr from vanadium slag using AlCl3 molten salt at a temperature range from 500 to 800 °C. Microwave heating chlorination kinetics was studied in a non-isothermal mode. The effects of the AlCl3/vanadium slag mass ratio and molten salt ratio on the extraction rate of chlorination peoducts were investigated. The structure and morphology evolution of microwave heating chlorination products were characterized by X-ray diffraction and scanning electron microscope with energy dispersive spectrometer. The results show that the highest extraction rate of the five elements (Fe, Mn, V, Cr, and Ti) can be achieved as 91.66%, 92.96%, 82.67%, 75.82% and 63.14%, when the mass ratios of AlCl3/vanadium slag and NaCl–KCl/AlCl3 are 1.5 and 1.66, respectively. These extraction rates in the microwave heating mode for 30 min are reached and exceeded by 6 h in the conventional heating method. Microwave heating will minimize the chlorination time and reduce the volatilization of AlCl3. Based on the thermodynamics and kinetic analysis, the different phases of vanadium slag can be chlorinated using AlCl3 in the range from 400 to 800 °C, and the olivine phase is superior to the spinel phase in chlorination. In addition, the chlorination rates of V and Cr are slower than those of Fe and Mn, and increasing the reaction time is advantageous for the chlorination of V and Cr. The chlorination of Fe and Mn is controlled by diffusion, and the non-isothermal diffusion activation energies of Fe and Mn are 17.02 and 17.10 kJ·mol−1, respectively. In contrast, the chlorination of V and Cr is limited in the interfacial chemical reaction step, for whom the activation energies give 40.00 and 50.92 kJ·mol−1, respectively. The combination effect of the microwave and molten salt on the chlorinating vanadium slag can be attributed to the enhancement of the diffusion and local chemical reaction.

Background and objective The Previous study has indicated that the incidence of venous thromboembolism (VTE) after lung cancer surgery is not uncommon. The aim of this study is to analyze the risk factors of postoperative VTE in lung cancer patients and provide a clinical basis for further prevention and treatment of VTE. Methods This study was a single-center study. From July 2016 to December 2017, all patients with lung cancer who underwent surgery in our department were enrolled into this study. Except routine preoperative examinations, lower extremity Doppler ultrasound was performed in all patients before and after surgery to determine whether there was any newly developed deep venous thrombosis (DVT). Patients did not receive any prophylactic anticoagulant therapy before and after surgery. Patients were then divided into VTE group and control group according to whether VTE occurred after operation. Baseline data, surgical related data (surgery type, surgical procedure, etc.) and tumor pathological data (pathological type, vascular infiltration, pathological staging, etc.) were compared between the two groups. Results According to the inclusion criteria, a total of 339 patients undergoing lung cancer surgery were analyzed. There were 166 males and 173 females with an age range of 23-86 years. A total of 39 patients developed VTE after surgery, the incidence rate of postoperative VTE was 11.5%. Comparing the age, gender, body mass index (BMI), American Society of Anesthesiologists (ASA), smoking status, underlying diseases, etc, there were no significant differences in other indicators except for significant differences in age; comparison between preoperative blood routine, blood biochemistry, coagulation, tumor markers, lung function, lower extremity venous ultrasound, preoperative carcinoembryonic antigen (CEA) levels, preoperative D-dimer levels, there were significant differences in lung function and lower extremity intermuscular vein expansion ratio. There were no significant differences in other indexes between the two groups. The duration of surgery, surgical procedure, bleeding volume, pathological type, pathological stage, vascular invasion, were compared between the two groups. There were statistical differences in surgical methods (thoracic vs thoracoscopic) and bleeding volume. There were no significant differences in other indicators. Univariate analysis showed that age, preoperative CEA level, preoperative D-dimer level, poor pulmonary function, lower extremity intermuscular vein dilation ratio, thoracotomy rate, length of surgery, and amount of bleeding were significantly risk factors (P

Abstract: With the drill string hole being regarded as an ultra-long irregular lossy cylindrical waveguide, the optimal frequency point for microwave transmission was calculated according to the electromagnetic wave coupling theory, the attenuation law and efficient transmission distance of microwave channel were obtained and the microwave mode in the waveguide was analyzed. Furthermore, the channel model and signal attenuation model were established by the microwave transmission equivalent circuit method. The power attenuation coefficient per unit of length was proposed to simplify the analysis on effective transmission distance for the ultra-long drill string. The optimal frequency points of 139.7 mm (5.5 in) and 127 mm (5 in) API drill pipes are 2.04 GHz and 2.61 GHz, respectively, and there are several inner diameter varying sections and break points in the drill string hole along the axial direction. The microwave transmission suffers a lot of reflections. The channel impedance change is a key factor affecting the transmission quality. The lab and field tests reveal that the attenuation model established in this paper is accurate, and it is applicable to the design of microwave transmission measurement while drilling system. Key words: gas drilling, measure while drilling, microwave transmission, drill string bore, optimal frequency point, cylindrical waveguide, effective transmission distance

Due to the problem that the congestion control algorithm of transmission control protocol (TCP) cannot meet the requirements of quality of experience for Internet video transmission, a semi-Markov decision process based conges-tion control algorithm for video transmission was proposed. First, in order to improve the accuracy of video quality as-sessment, an online operation no-reference video quality assessment was presented. Then, the congestion control problem was formulated as a semi-Markov decision process according to the feedback of video quality assessment, and the opti-mal parameters of congestion control were obtained by solving the semi-Markov decision process. Simulation results re-veal that proposed algorithm achieves better subjective and objective video quality, and obtains well TCP-friendliness ra-tio, compared with the conventional congestion control algorithms.

Objectives: To investigate the correlation between optimal placement depth (OPD) and physical measurement parameters in preterm infants receiving placement of peripherally inserted central catheter (PICC) through the great saphenous vein (GSV), and to establish a predictive formula for OPD during the placement of PICC through the GSV., Methods: A retrospective analysis was performed for the preterm infants who received the placement of PICC through the GSV in the Neonatal Intensive Care Unit of the Third Xiangya Hospital of Central South University from December 2022 to February 2024. According to the site of puncture [GSV of the knee joint (KJ) or the ankle joint (AJ)], they were divided into a GSV-KJ placement group ( n =38) and a GSV-AJ placement group ( n =33). The infants were measured in terms of body weight (BW), body length, the length of the upper and lower parts of the body, head circumference, and abdominal circumference at the time of placement. The Pearson correlation analysis was used to investigate the correlation between the above variables and OPD. A predictive formula was established for OPD in the placement of PICC via the GSV in preterm infants, and the predicted residual between the predicted depth and the ideal OPD was compared between the conventional predictive formula and the new predictive formula., Results: The Pearson correlation analysis showed that PICC OPD was significantly positively correlated with BW, body length, the length of the upper and lower parts of the body, head circumference, and abdominal circumference in both the GSV-KJ placement group and GSV-AJ placement group ( P <0.05), with the highest degree of correlation between OPD and BW. The univariate linear regression analysis showed a linear relationship between PICC OPD and BW in both groups. The predictive formulas for OPD were as follows: GSV-KJ PICC OPD (cm) = 13.1 + 2.7 × BW (kg) and GSV-AJ PICC OPD (cm) = 13.4 + 6.0 × BW (kg), and the new predictive formulas had a significantly lower predicted residual than the conventional predictive formula ( P <0.05)., Conclusions: OPD for PICC through the GSV is positively correlated with BW, and the prediction results of the new predictive formula based on BW are closer to the ideal OPD.

Objective: To study the effect of dexamethasone (DEX) on the expression of Dynein heavy chain (DHC) and Dynactin in the cytoplasm of fetal rat cerebral cortical neurons cultured in vitro ., Methods: Primary cerebral cortical neurons of fetal rats were cultured in vitro and were used to establish a cellular model of DEX intervention. According to the final concentration of DEX, the neurons were divided into three groups:control (without DEX), 0.1 μmol/L DEX, and 1.0 μmol/L DEX. On days 1, 3, and 7 after intervention, the quantitative PCR was used to observe the effect of DEX on the mRNA expression of DHC and Dynactin. The Western blot was used to observe the effect of DEX on the protein expression of DHC and Dynactin., Results: There was no significant difference in the mRNA expression levels of DHC and Dynactin among the three groups at all time points ( P > 0.05). On day 7 after DEX intervention, the protein expression of DHC in the 1.0 μmol/L DEX group gradually increased and reached the peak over time, which was significantly higher than that in the control and 0.1 μmol/L DEX groups ( P < 0.05). The control and 0.1 μmol/L DEX groups had a significant increase in the protein expression of Dynactin from day 1 to days 3 and 7 after DEX intervention ( P < 0.05). The control group had a significant increase in the protein expression of Dynactin from day 3 to day 7 after intervention ( P < 0.05), while the 0.1 μmol/L DEX group had a significant reduction in the protein expression of Dynactin from day 3 to day 7 after intervention ( P < 0.05). On days 3 and 7 after DEX intervention, the 0.1 μmol/L DEX and 1.0 μmol/L DEX groups had a significantly lower protein expression level of Dynactin in the cerebral cortical neurons than the control group ( P < 0.05). On day 7 after DEX intervention, the 1.0 μmol/L DEX group had a significantly lower protein expression level of Dynactin than the 0.1 μmol/L DEX group ( P < 0.05)., Conclusions: DEX affects the protein expression of DHC and Dynactin in the fetal rat cerebral cortical neurons cultured in vitro , possibly in a concentration- and time-dependent manner.

Objective: To study the value of quantitative electroencephalography (qEEG) in evaluating the effect of blood glucose on the brain function of preterm infants., Methods: The preterm infants who were admitted to the Department of Neonatology, The Third Xiangya Hospital of Central South University, from January to December 2019 were enrolled. According to the level of blood glucose, they were divided into group 1 (blood glucose <4.95 mmol/L), group 2 (blood glucose 4.95 to <6.60 mmol/L), group 3 (blood glucose 6.60 to <8.55 mmol/L), and group 4 (blood glucose ≥8.55 mmol/L). The changes in qEEG parameters were compared between groups, and a correlation analysis was performed for blood glucose and qEEG parameters., Results: A total of 39 preterm infants were enrolled (84 blood glucose measurements). Compared with group 4, the other three groups had significant increases in the total spectral power of each brain region and the absolute power of each frequency band in the frontal and occipital regions (P<0.05). The total spectral power, δ/θ ratio, and (δ+θ)/(α+β) ratio of each brain region were negatively correlated with blood glucose level, while the relative power of θ frequency band was positively correlated with blood glucose level (P<0.05)., Conclusions: With the change in blood glucose, there are significant changes in the total spectral power of each brain region, the power of each frequency band, and the frequency spectrum composition on qEEG in preterm infants. qEEG may therefore become an important tool to monitor the effect of abnormal blood glucose on brain function in preterm infants.

Objectives: To observe the electrophysiological changes of astrocytes in the process of hyperoxia induced apoptosis and analyze the relationship between electrophysiological characteristics and morphological changes., Methods: Astrocytes were exposed to 90% hyperoxia for 12-72 h. The electrophysiological characteristics of astrocytes in each group were detected by patch clamp technique, and the morphological characteristics of astrocytes were observed at the same time. Then the same batch of astrocytes were collected, and the expression levels of caspase-1, caspase-3, gasdermin D (GSDMD) and gasdermin E (GSDME) were detected by Western blotting., Results: From 12 h to 72 h after hyperoxia exposure, the inward current was significantly lower than that of the control group ( P <0.05), while the outward current was significantly decreased at 12 h and increased at 48 h ( P <0.05). There was no significant difference between 24 h or 72 h after hyperoxia exposure and the control group ( P >0.05). At each time point, the morphology of cells changed correspondingly. Western blotting showed that the expression of caspase-1 was increased significantly at 24 h and decreased significantly at 72 h after hyperoxia exposure ( P <0.05); the expression of GSDMD was increased at 12 h and decreased gradually from 24 h to 72 h after hyperoxia exposure ( P <0.05); the expression of caspase-3 did not change significantly at 12 h and 24 h after hyperoxia exposure ( P >0.05), but began to decrease at 48 h ( P <0.05); GSDME increased gradually at 24 h after hyperoxia exposure ( P <0.05)., Conclusions: Under hyperoxia exposure, the ion channels of astrocytes are damaged, which can maintain the dysfunction of ion homeostasis, activate GSDME, induce the damaged cells to break away from the apoptotic pathway, and mediate the pyroptosis.

Objective: To investigate the current status of antibiotic use for very and extremely low birth weight (VLBW/ELBW) infants in neonatal intensive care units (NICUs) of Hunan Province., Methods: The use of antibiotics was investigated in multiple level 3 NICUs of Hunan Province for VLBW and ELBW infants born between January, 2017 and December, 2017., Results: The clinical data of 1 442 VLBW/ELBW infants were collected from 24 NICUs in 2017. The median antibiotic use duration was 17 days (range: 0-86 days), accounting for 53.0% of the total length of hospital stay. The highest duration of antibiotic use was up to 91.4% of the total length of hospital stay, with the lowest at 14.6%. In 16 out of 24 NICUs, the antibiotic use duration was accounted for more than 50.0% of the hospitalization days. There were 113 cases with positive bacterial culture grown in blood or cerebrospinal fluid, making the positive rate of overall bacterial culture as 7.84%. The positive rate of bacterial culture in different NICUs was significantly different from 0% to 14.9%. The common isolated bacterial pathogens Klebsiella pneumoniae was 29 cases (25.7%); Escherichia coli 12 cases (10.6%); Staphylococcus aureus 3 cases (2.7%). The most commonly used antibiotics were third-generation of cephalosporins, accounting for 41.00% of the total antibiotics, followed by penicillins, accounting for 32.10%, and followed by carbapenems, accounting for 13.15%. The proportion of antibiotic use time was negatively correlated with birth weight Z-score and the change in weight Z-score between birth and hospital discharge (r s =-0.095, -0.151 respectively, P<0.01), positively correlated with death/withdrawal of care (r s =0.196, P<0.01)., Conclusions: Antibiotics used for VLBW/ELBW infants in NICUs of Hunan Province are obviously prolonged in many NICUs. The proportion of routine use of third-generation of cephalosporins and carbapenems antibiotics is high among the NICUs.

Objective: To study heart rate variability (HRV) in neonates with non-benign tachyarrhythmia (NNTA) and the role of automatic nervous system (ANS) in NNTA., Methods: The neonates who were admitted to the Department of Neonatology, the Second Xiangya Hospital of Central South University, from January 2010 to June 2018 and were diagnosed with NNTA were enrolled as the NNTA group, and the neonates with sinus rhythm or accidental premature beats on ambulatory electrocardiography were enrolled as the control group. Each group was further subdivided into preterm and term subgroups. A retrospective analysis was performed for their clinical data., Results: A total of 27 NNTA neonates were enrolled, accounting for 0.28% (27/9 632) of all neonates hospitalized during the same period of time, and 53 neonates were enrolled in the control group. Compared with the preterm and term control subgroups, the preterm NNTA and term NNTA subgroups had a significant increase in the standard deviation of average RR interval (P<0.05)., Conclusions: Immature and unbalanced ANS function may play an important role in the development and progression of NNTA.

Objective: To investigate the effect of corticosterone on the expression of the neuronal migration protein lissencephaly 1 (LIS1) in developing cerebral cortical neurons of fetal rats., Methods: The primary cultured cerebral cortical neurons of fetal Wistar rats were divided into control group, low-dose group, and high-dose group. The neurons were exposed to the medium containing different concentrations of corticosterone (0 μmol/L for the control group, 0.1 μmol/L for the low-dose group, and 1.0 μmol/L for the high-dose group). The neurons were collected at 1, 4, and 7 days after intervention. Western blot and immunocytochemical staining were used to observe the change in LIS1 expression in neurons., Results: Western blot showed that at 7 days after intervention, the low- and high-dose groups had significantly higher expression of LIS1 in the cytoplasm and nucleus of cerebral cortical neurons than the control group (P<0.05), and the high-dose group had significantly lower expression of LIS1 in the cytoplasm of cerebral cortical neurons than the low-dose group (P<0.05). Immunocytochemical staining showed that at 1, 4, and 7 days after corticosterone intervention, the high-dose group had a significantly lower mean optical density of LIS1 than the control group and the low-dose group (P<0.05). At 7 days after intervention, the low-dose group had a significantly lower mean optical density of LIS1 than the control group (P<0.05)., Conclusions: Corticosterone downregulates the expression of the neuronal migration protein LIS1 in developing cerebral cortical neurons of fetal rats cultured in vitro, and such effect depends on the concentration of corticosterone and duration of corticosterone intervention.

Objective: To explore the risk factors of Schistosoma japonicum infection in the residents in Xingzi County, Jiangxi Province., Methods: Six administrative villages from different areas were randomly selected by the cluster sampling method as the study sites in Xingzi Country in 2013, and all the residents aged 5 years or above were investigated epidemiologically, and the schistosome infection was surveyed by Kato-Katz technique. The risk factors of schistosomiasis were analyzed by using the Chi-square test analysis and multivariate Logistic regression model., Results: In 2013, there were 2 050 residents received the stool examination and 146 persons were positive, the schistosome infection rate was 7.1%. The Chi-square test showed that gender, age, occupation and education level were associated with the population infection rate ( χ 2 = 26.485、16.836、25.700、 90.805, all P < 0.05). The multivariate Logistic regression mode showed that the probability of schistosomiasis for the male was 3.041 times as much as that for the female; the probability of schistosomiasis for the illiteracy and primary education level crowd was 8.870 times as much as that for the college degree or above crowed; the probability of schistosomiasis for the junior middle school education level crowd was 5.598 times as much as that for the college degree or above crowed; the probability of schistosomiasis for the high school education level crowd was 2.995 times as much as that for the college degree or above crowed; the probability of infection of fishermen was the highest, which was 3.053 times as much as that for the other professional crowds., Conclusions: The risk factors of schistosome infection mainly include gender, occupation and the education level. We should strengthen the health education of schistosomiasis control, protection against the infested water contact, and so on.

Objective: To investigate the results of Gesell Developmental Scale in follow-up of preterm infants and to determine possible high-risk factors for poor long-term neurological outcome., Methods: A preterm infants' questionnaire was designed, and a retrospective study was conducted on the clinical data of 181 preterm infants (corrected age 2-12 months) and their mothers. The developmental quotient (DQ) scores were determined by the Gesell Developmental Scale and statistically analyzed., Results: Compared with those with a birth weight (BW) of ≥1 500 g, the preterm infants with a BW of <1 500 g had significantly reduced DQ scores of adaptability, gross motor movement, and fine movement (P<0.05). Compared with those with a gestational age (GA) of ≥32 weeks, the preterm infants with a GA of <32 weeks had significantly reduced DQ scores of adaptability, gross motor movement, fine movement, and social contact (P<0.05). DQ scores on five Gesell subscales were significantly positively correlated with GA and BW (P<0.05). The DQ scores on Gesell subscales showed a significant negative correlation with severe complications in neonatal period (P<0.001)., Conclusions: For preterm infants, BW <1 500 g and GA <32 weeks are high-risk factors for abnormal adaptability, gross motor movement, fine movement, and social contact, and this group of infants should be followed up closely. Severe complications in neonatal period may be associated with poor long-term neurological outcome and should be effectively prevented and treated.

Cone beam computer tomography (CBCT) has advantages of high precision, low radiation and high image quality. It has been developing quickly since it was applied clinically. In order to control X-ray TUBE HEAD effectively in Dental CBCT, X-ray TUBE HEAD Control System was designed and realized in this study. This control system is the core of CBTC system, which includes the communication between CBCT system and computer, the control of X-ray tube head by CBCT system main control board and the synchronization between main control board and the flat panel detector. Control circuit of the control system and corresponding operating software were designed with PIC16F877A as the core. This control system has been put into use in current CBCT system successfully.

Objective: To study the changes of glucocorticoid receptor (GR) expression in embryonic rat cortical neurons exposed to transient Mg(2+)-free treatment., Methods: Six days after rat cortical neuronal cultures, two groups were created based on the medium to which were transiently exposed. The control group was exposed to a physiological solution (PS), and the Mg(2+)-free group was exposed to the same medium as the control group except for the removal of magnesium. The expression of GR mRNA and protein was determined by real-time PCR and immunocytochemistry staining 1, 7 and 12 days after transient Mg(2+)-free treatment., Results: Compared to the control group, the Mg(2+)-free group displayed the significantly less accumulated optical density (AOD) of GR immunoreactivity 12 days after transient Mg(2+)-free treatment (p<0.05). On the contrary, GR mRNA expression increased significantly 1 and 7 days after transient Mg(2+)-free treatment in the Mg(2+)-free group (p<0.05)., Conclusions: GR expression is modified following Mg-free-induced injury in cultured developing neurons in rats.

Objective: To investigate the effets of flurothyl-induced neonatal recurrent seizures on glucocorticoid receptor (GR) expression in the rat brain., Methods: Forty-eight seven-day-old Sprague-Dawley rats were randomly divided into two groups: control and seizure. Seizures were induced by inhalant flurothyl daily for six consecutive days. Brains were sampled on postnatal days 13, 15 and 19. The expression of GR protein in the cerebral cortex was detected by Western blot and immunohistochemical method., Results: The expression of GR in the cerebral cortical plasma protein was significantly lower in the seizure group than in the control group on postnatal day 15. The expression of GR protein in the cerebral cortical nuclear protein decreased significantly in the seizure group compared with that in the control group on postnatal days 15 and 19 (p<0.05). Compared to the control group, the accumulated optical density (AOD) of GR immunoreactivity (IR) decreased significantly in the parietal cortex on postnatal day 13 (p<0.05), the AOD of GR IR decreased significantly in the parietal cortex and the temporal cortex on postnatal day 15 (p<0.05), and the AOD of GR IR decreased significantly in the parietal cortex, temporal cortex and the frontal cortex in the seizure group on postnatal day 19 (p<0.05)., Conclusions: Recurrent seizures in neonatal rats result in abnormal GR expression in the cerebral cortex which might play an important role in short-term brain injury induced by early recurrent seizures.

Objective: To evaluate the efficacy and safety of ganciclovir therapy for congenital cytomegalovirus (CMV) infection in newborn infants., Methods: The randomized controlled trials (RCTs) and quasi-RCTs on ganciclovir therapy for congenital CMV were reviewed in the following electronic databases: PubMed (January 1988 to January 2009), EMbase (January 1988 to January 2009), the Cochrane library (Issue 3, 2003 and Issue 1, 2009), the Chinese Journals Full-text Database (January 1994 to January 2009), the Chinese Biological Medical Disc (January 1994 to January 2009) and the Chinese Medical Current Contents (January 1994 to January 2009). Quality assessment, data extraction, and meta analysis were performed., Results: Ten papers were included. Meta analysis showed that the ganciclovir therapy increased the improvement rate (91.4% vs 34.0%; p<0.01) and led CMV infection indexes to become negative in more patients (87.6% vs 15.3%; p<0.01) and decreased incidence of hearing disturbance (4.7% vs 37.2%; p<0.01) as compared with the non-ganciclovir therapy control group. The incidence of the ganciclovir-therapy-related side effects was low., Conclusions: Ganciclovir treatment may increase the improvement rate and the rate of CMV infection indexes becoming negative, and decrease incidence of hearing disturbance, with few side effects, in newborn infants with CMV infection. However the supporting evidence is not strong due to few trials and more high-quality research is needed.

Objective: Ganciclovir is a first-line drug for treatment of cytomegalovirus (CMV) infection. However, some ganciclovir treatment-related side-effects can be found. This study aimed to compare the efficacy and side effects of relatively low and high doses of ganciclovir in the treatment of neonatal congenital CMV infection., Methods: One hundred and sixty-seven neonates with congenital CMV infection were randomly assigned to high-dose (n=79) and low-dose ganciclovir groups (n=88). The high-dose ganciclovir group was injected with ganciclovir of 7.5 mg/kg in the inducement phase and of 10 mg/kg in the maintaining phase. The low-dose ganciclovir group was injected with ganciclovir of 5 mg/kg in the inducement and the maintaining phases. The efficacy and side effects were observed in the two groups., Results: After treatment the clinical symptoms and signs were obviously improved in both groups. CMV-IgM became negative in 93.8% of neonates in the high-dose ganciclovir group and 93.1% of neonates in the low-dose ganciclovir group (P>0.05). CMV-DNA became negative in 80.8% of neonates in the high-dose ganciclovir group and in 86.7% in the low-dose ganciclovir group (P>0.05). The low-dose ganciclovir group had lower incidence of side effects than the high-dose ganciclovir group: vomiting 2.3% vs 11.4%; anemia 8.0% vs 20.3%; reduction of neutrophilic granulocytes 5.7% vs 16.5%; increase in platelet count 8.0% vs 18.9% (P<0.05)., Conclusions: Low-dose ganciclovir has the same clinical efficacy to high-dose ganciclovir for treatment of neonatal congenital CMV infection, but fewer side effects occur in the low-dose group.

Objective: To investigate the short-term effects of flurothyl-induced neonatal recurrent seizures on gamma-aminobutyric acid A receptor (GABAAR) alpha1 and beta2 subunit expression in the rat brain, and to study the relationship between the alterations of GABAAR subunits in the developing brain and seizure-induced brain injury., Methods: Sixty-four 7-day-old Sprague-Dawley rats were randomly divided into two groups: control and seizure. Seizures were induced by inhalant flurothyl daily for six consecutive days. The expression of GABAAR alpha1 and beta2 subunits protein in the cerebral cortex and the hippocampus were detected by Western blot and immunohistochemistry method 1 and 7 days after recurrent seizures., Results: Compared to the control, the accumulated optical density (AOD) of GABAAR alpha1 subunit immunoreactivity (IR) in the parietal cortex, the CA3-CA4 regions and the dentate gyrus in seizure rats increased significantly 1 day after recurrent seizures (P<0.05). The AOD of GABAAR alpha1 subunit IR in the parietal cortex, the CA1-CA4 regions and the dentate gyrus in seizure rats increased significantly 7 days after recurrent seizures compared with the control (P<0.05). The expression of GABAAR alpha1 subunit in the hippicampus and the cerebral cortex increased significantly in seizure rats compared with that in control rats 1 and 7 days after recurrent seizures. After 7 days of recurrent seizures, the AOD of GABAAR beta2 subunit IR in the CA1-CA2 regions increased significantly in the seizure group compared with that in the control group (P<0.05), but the AOD of GABAAR beta2 subunit IR in the thalamus decreased significantly in the seizure group compared with that in the control group (P<0.05). The expression of GABAAR beta2 subunit protein in the hippocampus increased significantly in the seizure group compared with that in the control group 7 days after recurrent seizures (P<0.05)., Conclusions: Recurrent neonatal seizures may result in the short-term alterations of GABAAR alpha1 and beta2 subunits expression in the cerebral cortex and the hippocampus in rats, suggesting the alterations of GABAAR subunit expression may be related to the developing brain injury following recurrent seizures.

Objective: To investigate the long-term effects of recurrent seizures in neonate period on the expression of gamma-aminobutyric acid A receptor (GABAAR) alpha1 and beta2 subunits in brain and spatial memory and seizure susceptibility in adult period., Methods: Thirty-two 7-day-old SD rats were randomly divided into 2 equal groups: seizure group, inhaling flurothyl to induce seizure daily for 6 days, and control group. On days 61 - 65 after birth Morris water maze test was used to record the escape latency. On day 75 after birth pentylenetetrazol (PTZ) was injected intraperitoneally to induce seizure so as to record the latency. Then the rats were killed to take their brains, 8 in each group used to undergo immunohistochemistry to examine the protein expression of the GABAAR alpha1 and beta2 subunits, and the other 8 in each group used to examine the mRNA expression of the GABAAR alpha1 and beta2 subunits in the brains using RT-PCR., Results: On day 64 the escape latency of the seizure group was 82,424 ms +/- 35,622 ms, significantly longer than that of the control group (40,712 ms +/- 29,468 ms, P = 0.001). On day 75 the frequency of crossing target within 120 s in the water maze of the seizure group was 1.2 times +/- 0.9 times, significantly less than that of the control group (3.1 times +/- 1.3 times, P < 0.01). The seizure latency after the PTZ injection of the seizure group was (1487 +/- 662) s, not significantly different from that of the control group (1841 s +/- 648 s, P = 0.133). In comparison with the control group the accumulated optical density (AOD) of GABAAR alpha1 subunit protein immunoactivity in the parietal cortex, and hippocampal CA1-2 and CA4 regions of the seizure group decreased significantly (all P < 0.05), and was not significantly different in the frontal cortex, dentate gyrus, and hippocampal CA3 region (all P > 0.05). In comparison with the control group the accumulated optical density (AOD) of GABAAR beta2 subunit protein immunoactivity in the thalamus, and hippocampal CA1-4 regions of the seizure group decreased significantly (all P < 0.05), and was not significantly different in the frontal cortex and parietal cortex (both P > 0.05). In comparison with the control group the mRNA expression of GABAAR alpha1 subunit and the mRNA expression of GABAAR beta2 subunit of the seizure group were significantly lower in the hippocampus (both P < 0.05) and not significantly different in the cerebral cortex (both P > 0.05)., Conclusion: Recurrent seizures in neonate period modify the expression of GABAAR alpha1 and beta2 subunits in the cerebral cortex and hippocampus in adult period which may be related to cognitive deficit.

Objective: To investigate the long-term effects of flurothyl-induced neonatal recurrent seizures on GABA A receptor (GABA(A)R) alpha1 and gamma2 subunit expressions in adult rat brain, and discuss the relationship between these alterations of GABA(A)R subunits in mature brain and the changes of spatial memory and seizure susceptibility in adult rats., Methods: Thirty-two of 7-day-old (P7) Sprague-Dawley rats were divided randomly into two groups: the control group and the seizure group. Seizures were induced by inhalant flurothyl daily for six consecutive days. Rats were tested for spatial memory by using the Morris water maze task from postnatal 61 d(P61) to P65. Seizure threshold was examined by intraperitoneal injection of pentylenetetrazol, and then the brains were sampled on P75. The expressions of GABA(A)R alpha1 and gamma2 subunits mRNA and protein in cerebral cortex and hippocampus were detected by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry method., Results: On P64, the escape latencies in water maze for the rats in the seizure group were significantly longer than those of the control rats [(82 424+/-35 622)ms vs (40 712+/-29 468)ms, P=0.001]. On P65, the frequency of crossing target within 120 s in water maze for the rats in the seizure group were significantly less than those of the control rats [(1.2+/-0.9) vs (3.1+/-1.3), P<0.001]. There was no difference in seizure threshold between the two groups on P75 [(1 487+/-662)s vs (1 841+/-648)s, P=0.137]. Compared to the control rats, the accumulated optical density (AOD) of GABA(A)R alpha1 subunit immunoreactivity in seizure rats decreased significantly in the parietal cortex, CA1-2 and CA4 region (P<0.05). The AOD of alpha1 subunit protein immunoreactivity in the frontal cortex, CA3 and dentate gyrus (DG) were of no significant difference between the two groups on P75 (P>0.05). There were also no differences in the AOD of gamma2 subunit protein immunoreactivity in the parietal lobe, DG, and CA1-3 region between the two groups (P>0.05). The AOD of gamma2 subunit protein immunoreactivity in the frontal lobe and CA4 region decreased significantly in the seizure group than those in the control group (P<0.05). The expressions of alpha1 subunits mRNA in the cerebral cortex and gamma2 subunit mRNA in the hippocampus were similar between the two groups (P>0.05), but the expressions of alpha1 subunits mRNA in the hippocampus and gamma2 subunit mRNA in the cerebral cortex in the seizure group decreased significantly as compared with those in the control group (P< 0.05)., Conclusion: Recurrent seizures in neonatal rats modify GABA(A) receptor alpha1 and gamma2 subunits expression in the cerebral cortex and hippocampus of adult rats, and cause long-term cognitive deficit, Which suggests that abnormal GABA(A) receptor expression might play an important role in long-term cognitive deficit induced by early life recurrent seizures.

Objective: This study investigated the effects of flurothyl-induced neonatal recurrent seizures on gamma-aminobutyric acid B1 receptor (GABAB1R) expression in neonatal and adult rat brain, and explored the possible relationship between the alterations of GABAB1R in mature brain and the changes of spatial memory and seizure susceptibility in adult rats., Methods: Forty-eight postnatal day (P) 7 Sprague-Dawley rats were randomly assigned into two groups: Control and Seizure group (n=24 each). Seizures were induced by inhalant flurothyl daily for six consecutive days in rat pups from the Seizure group. Twelve rats selected randomly in each group were sacrificed on the 7th day after the last seizure for detecting the expressions of GABAB1R mRNA and protein in cerebral cortex and hippocampus by reverse transcription-polymerase chain reaction (RT-PCR) and immuno-histochemistry method. The spatial memory was tested by using the Morris water maze task during P61 to P64 and the seizure threshold was measured at P75 following intraperitoneal injection of pentylenetetrazol ( PTZ ) in the remaining rats. The rats were then sacrificed for detecting the expressions of GABAB1R mRNA and protein in cerebral cortex and hippocampus., Results: The expressions of GABAB1R mRNA and protein in the cerebral cortex on the 7th day after the last seizure and at P75 decreased significantly in the Seizure group when compared with the Control group (P < 0.05). The GABAB1R protein expression in the dentate gyrus on the 7th day after the last seizure in the Seizure group was significantly lower than that in the Control group (P < 0.05), but the GABAB1R mRNA expression in the hippocampus was not different from that in the Control group. There were no significant differences in the expressions of GABAB1R mRNA and protein in the hippocampus between the two groups at P75. The escape latencies in water maze of the rats in the Seizure group at P64 were significantly longer than those in the Control group (98,533.8 +/- 27,205.4 ms vs 46,723.3 +/- 40,666.5 ms; P <0.05). There were no differences in the seizure threshold between the two groups., Conclusions: The expressions of GABAB1R mRNA and protein in the cerebral cortex and hippocampus of neonatal rats with recurrent seizures decreased significantly, suggesting the changes of GABAB1R may be related to acute brain injury following neonatal recurrent seizures and the memory deficit in adult rats caused by neonatal recurrent seizures.

Objective: The expressions of caspase-1 and cytokines activated by caspase-1 are associated with the pathophysiology of many diseases for its proinflammatory and proapototic peculiarity. However its relationship to brain injury of developing rats following recurrent seizures has not yet been identified. This study aimed to investigate the role of caspase-1 and cytokines activated by caspase-1 in brain injury of developing rats following recurrent seizures., Methods: A total of 96 postnatal 20 day Sprague-Dawley rats were randomly assigned into Control and Seizure groups. Seizures were induced in the Seizure group by flurothyl inhalation daily for six days. Brain tissues were sampled at 6 hrs, and at 1, 3, and 7 days after last seizure. The expressions of caspase-1, interleukin (IL)-18 and IL-1beta mRNA in the cerebral cortex were detected by RT-PCR. The water content of the brain and the pathological changes of cortex nerve cells were observed. Brain injury was evaluated using a semiquantitative neuropathological scoring system., Results: The levels of caspase-1 and IL-18 mRNA in the cerebral cortex of the Seizure group were obviously higher than those in the Control group at 6 hrs, and at 1, 3, and 7 days after seizure (P < 0.05 or P < 0.01). The expression of IL-1beta mRNA in the Seizure group exhibited a biphasic pattern: increased significantly at 6 hrs, and at 1 and 7 days post-seizure (P < 0.01), but was not significantly different from the Control group at 3 days post-seizure. Edema, degeneration and necrosis of nerve cells in cerebral cortex, accompanying by inflammatory cell infiltration and apoptosis of nerve cells, were observed under a light microscope in the Seizure group after recurrent seizures. The water content of the brain in the Seizure group increased significantly compared with that in the Control group at 6 hrs, and at 1 and 3 days after recurrent seizures (P < 0.01). The Seizure group had significantly higher neuropathological scores than the Control group at each time point (P < 0.01)., Conclusions: Caspase-1 and cytokines activated by caspase-1 play an important role in the developing brain injury after recurrent seizures.

Objective: To study the protection of IL-1ra in cultured developing neuron injury following Mg(2+)-free-induced epileptiform discharges., Methods: Rat embryo cortical neurons cultured for 6 d and 17 d were directly exposed to Mg(2+)-free media, or pretreated with IL-1 receptor antagonist or NMDA receptor antagonists before being exposed to Mg(2+)-free media, and then returned to regular media.MTT assay was used to study mitochondrial function injury, laser-scanning confocal microscope to measure [Ca(2+)]i, and real-time RT-PCR to detect gene mRNA expression., Results: (1) MTT conversion rates were higher in neurons pre and co treated with 10 mg/L IL-1ra than those of neurons with only Mg(2+)-free treatment in neurons cultured for 17 d, but not in neurons cultured for 6 d.(2) [Ca(2+)]i was lower in neurons pre and co-treated with 10 mg/L IL-1ra than those of neurons with only Mg(2+)-free treatment, either in neurons cultured for 6 d or in neurons cultured for 17 d, and the effects of IL-1ra on [Ca(2+)]i change were different between neurons cultured for 6 d and neurons cultured for 17 d.(3) Pre and co-treated with 10 mg/L IL-1ra NR1 mRNA expression increase induced by Mg(2+)-free treatment was decreased, either in neurons cultured for 6 d or neurons cultured for 17 d, and this effect showed no difference between neurons cultured for 6 d and 17 d; Pre and co-treated with 10 mg/L IL-1ra NR2A mRNA expression increase induced by Mg(2+)-free treatment in neurons cultured for 17 d was decreased, and NR2A mRNA expression showed no difference between IL-1ra group and age-matched control group, but have no effect on neurons cultured for 6 d; Pre and co-treated with 10 mg/L IL-1ra have NR2B mRNA expression increase induced by Mg(2+)-free treatment was not affected, either in neurons cultured for 6 d or neurons cultured for 17 d., Conclusion: Neuroprotection of IL-1Ra in seizure-induced injury is age-dependent. The mech-anism of the neuroprotection of IL-1Ra includes down-regulation of [Ca(2+)]i and others.

Objective: To investigate the survival, division, and differentiation of neural precursor cells (NPCs) following glucose-free treatment in vitro., Methods: Cultured neonatal rat hippocampal NPCs were exposed to glucose-free media for 6 hours, and then were returned to regular media containing normal level glucose. At different time points after glucose-free treatment, trypan blue staining was used to determine cell viability, MTT assay to measure cell metabolic rate, 5'-bromo-deoxyuridine (BrdU) incorporation to determine the NPCs division, and immunocellulochemistry and western blot analysis to study the NPCs differentiation., Results: (1) At different time points (0, 1, 7 d) after glucose-free treatment, NPCs viability decreased compared with NPCs control. On 0 and 1 d after glucose-free treatment, NPCs viability was higher than neurons viability. (2) On 0 and 1 d after glucose-free treatment, NPCs metabolic rates decreased significantly compared with NPCs control. On 0, 1, and 7 d after glucose-free treatment, NPCs metabolic rates were higher than that in neurons. (3) After glucose-free treatment, BrdU incorporation of NPCs was similar to NPCs control (P>0.05). (4) After glucose-free treatment, NPCs differentiation didn't change significantly (P>0.05)., Conclusion: These findings demonstrated that glucose-free treatment impaired NPC's viability, but didn't affect the division and differentiation of NPCs.

Objective: To study the long-term effect of flurothyl-induced recurrent seizures in neonatal rats on cognition, seizure susceptibility, and NMDA receptor expression in adult rat brain., Methods: Seizures were induced by inhalant flurothyl for 6 days, starting from postnatal day 6 (P6). On P60, rats were tested for spatial memory by using the Morris water maze task. Seizure threshold was examined by intraperitoneal injection of pentylenetetrazol (PTZ) on P75. Brain homogenates were made at the same time. Expression of NMDA receptor protein in cerebral cortex and hippocampus was examined with Western blotting analysis., Results: Compared with the control group, flurothyl-treated rats showed significant spatial deficits in the Morris water maze on P60. There was no difference in seizure threshold. In the cerebral cortex of flurothyl-treated rats, the protein expressions of NR1, NR2A, and NR2B decreased significantly, but NR2C increased significantly. In the hippocampus of flurothyltreated rats, the protein expression of NR2A decreased significantly, the protein expression of NR2C increased significantly, and NR1 and NR2B were similar to that in the hippocampus of control group., Conclusion: Recurrent seizures in neonatal rats might cause long-term cognitive deficit and modify NMDA receptor subunit expressions in cerebral cortex and hippocampus of adult rats. This phenomenon raised the possibility that abnormal NMDA receptor expression might play an important role in long-term cognitive deficit induced by early life recurrent seizures.

Objective: To study cortical neuron injury following recurrent epileptiform discharges induced by magnesium-free treatment in vitro., Methods: Cultured embryo cortical neurons were exposed to magnesium-free media for 3 h, then they were returned to regular media containing normal level magnesium. At different time after Mg(2+)-free treatment, trypan blue staining and determination of LDH activity were used to determine the cell viability, flow cytometry was applied to measure neuronal apoptosis, and MTT assay to study metabolic rate., Results: (1) Neuronal morphology on light microscopy following Mg(2+)-free treatment showed that there were no prominent alterations. (2) At different time (6, 12, 72 h) after Mg(2+)-free treatment, neuronal viability by trypan blue staining and LDH activity showed modest changes compared with time-matched control in different culture days (6, 12, 17 d) (P > 0.05). (3) Cell apoptosis increased mildly at different time after Mg(2+)-free treatment in neurons cultured for different days, but the increase was not significant (P > 0.05). (4) Metabolic rate decreased at 6 h after Mg(2+)-free treatment (P < 0.05) in neurons cultured for 6 d, and was 86.4% of that of the control; while the rate at 24 h in neurons cultured for 12 d and 17 d also decreased (P < 0.05), being 78.7% and 70.9%, respectively, of that of the control., Conclusions: These findings demonstrated that the injury occurred on cultured cortical neurons caused by magnesium-free-treatment-induced recurrent epileptiform discharges was mainly functional and relatively mature neurons displayed more severe and much later mitochondrial function impairment than immature neurons.

A method has been developed for the determination of sildenafil in the medicines for erectile dysfunction by capillary electrophoresis. The samples were analyzed with 60 mmol/L NaH2PO4(pH 5.0) running buffer at 35 degrees C capillary temperature and 30 kV voltage. A linear calibration was obtained from 0.07 g/L to 1.05 g/L of sildenafil (r = 0.9985) with the RSD of 4.7% for peak area, and the average recovery was 97.4%. The results were compared with those of HPLC, showing that the method is precise, simple and cost-effective, and can be used as a complementary method to HPLC.