EEG microstate analysis reveals large-scale brain network alterations in depressed adolescents with suicidal ideation

BACKGROUND

Accumulating evidence showed abnormalities in brain network connectivity in depressive individuals with suicidal ideation (SI). We aimed to investigate the large-scale brain network dynamics in adolescents with SI and major depressive disorder (MDD).

METHODS

We recruited 47 first-episode drug-naïve adolescents with MDD and SI, 26 depressed adolescents without SI (noSI), and 26 age-matched healthy controls (HC). The Columbia Suicidal Ideation Severity Scale (C-SSRS) was utilized to assess suicide ideation. We acquired 64-channel resting-state EEG recordings from all subjects and used microstate analysis to investigate the large-scale brain network dynamics.

RESULTS

We observed a significant reduction in the occurrence and coverage of microstate B within the SI group when contrasted with the noSI group. Conversely, there was a significant increase in the occurrence and coverage of microstate A in the SI group as compared to the HC group. Additionally, we observed heightened transition probabilities from microstates D and C to microstate A in the SI group; meanwhile, transitions from microstate D to B were more prevalent in the noSI group. Furthermore, the noSI group exhibited a significant decline in the transition probabilities from microstate D to microstate C.

LIMITATIONS

The cross-sectional nature limits the capacity to determine whether microstate dynamics have prognostic significance for SI.

CONCLUSION

We provided evidence that depressed adolescents with SI have a distinct pattern in microstate dynamics compared to those without SI. These findings suggest that microstate dynamics might serve as a potential neurobiomarker for identifying SI in depressed adolescents.

[Minimally invasive liver surgery:progress in the last decade and evolving trends]

With the promotion and popularity of minimally invasive surgery and instruments,minimally invasive technologies have been widely used in the diagnosis and treatment of liver disease. In the past decade,with the development of relevant instruments,improvement of skills,and perfection of theories,the concept of individualized minimal invasion and precision has been popularized. Minimally invasive liver surgery is moving toward the goal of innovation-driven high-quality development.

Neurophysiological biomarkers for depression classification: Utilizing microstate k-mers and a bag-of-words model

Microstates are analogous to characters in a language, and short fragments consisting of several microstates (k-mers) are analogous to words. We aimed to investigate whether microstate k-mers could be used as neurophysiological biomarkers to differentiate between depressed patients and normal controls. We utilized a bag-of-words model to process microstate sequences, using k-mers with a k range of 1-10 as terms, and the term frequency (TF) with or without inverse-document-frequency (IDF) as features. We performed nested cross-validation on Dataset 1 (27 patients and 26 controls) and Dataset 2 (34 patients and 30 controls) separately and then trained on one dataset and tested on the other. The best area under the curve (AUC) of 81.5% was achieved for the model with L1 regularization using the TF of 4-mers as features in Dataset 1, and the best AUC of 88.9% was achieved for the model with L1 regularization using the TF of 9-mers as features in Dataset 2. When Dataset 1 was used as the training set, the best AUC of predicting Dataset 2 was 74.1% for the model with L2 regularization using the TF-IDF of 9-mers as features, while the best AUC of predicting Dataset 1 was 70.2% for the model with L1 regularization using the TF of 8-mers as features. Our study provided novel insights into the potential of microstate k-mers as neurophysiological biomarkers for individual-level classification of depression. These may facilitate further exploration of microstate sequences using natural language processing techniques.

A resting-state electroencephalographic microstates study in depressed adolescents with non-suicidal self-injury

Neuroimaging studies have revealed abnormal brain activities in depressed teenagers who engage in non-suicidal self-injury (NSSI). We used resting-state electroencephalography (EEG) microstate analysis, which indicates the brief overlap of brain network activation for exploring the characteristics of large-scale cortical activities in depressed adolescents engaged with NSSI to clarify the underlying temporal mechanism. A modified k-means cluster algorithm was used to segment 64-channel resting-state EEG data into microstates. Data from 27 healthy adolescents, 37 adolescents with major depressive disorder (MDD), and 53 adolescents with both MDD and NSSI were examined in this study. The resting-state microstate parameters were compared among groups using the one-way ANOVA and Spearman correlation. Then the associations between significantly different microstate parameters and the depressive severity and self-harming data in the patient groups were further analyzed. The MDD group had higher contribution (p < 0.01), occurrence (p < 0.01) of microstate A, and higher microstate E→A transition (p < 0.05) than the HC and the NSSI group. The MDD group showed a distinctly longer duration (p < 0.05) of microstate A and microstate A→C transition than the HC. The transition probability from B to C was increased in the NSSI group compared to the HC. In the MDD group, the HAMD correlated with the duration of microstate A (Spearman's rho = 0.34, p = 0.044), as the PHQ-9 correlated with its occurrence (Spearman's rho = 0.37, p = 0.028). This research revealed that whereas depressive adolescents with NSSI and MDD displayed similar patterns with healthy controls in EEG microstate, the MDD group did not. Additionally, the non-random transition from microstate E→A may protect against recent self-harm in adolescents with MDD.

[Distribution and reference intervals of daytime intraocular pressure in the eye health screening population of Handan]

Objective: To describe the distribution and establish reference intervals (RI) of daytime intraocular pressure (IOP) in the eye health screening population of Handan. Methods: This cross-sectional study included subjects who participated in eye health screening at the Physical Examination Center of Handan First Hospital from May 2021 to June 2022. A complete general and ocular examination was performed, including measurements of visual acuity and IOP (using Goldmann tonometry), slit lamp microscopy, fundus photography, and anterior and posterior segment optical coherence tomography. Subjects with factors that could cause significant changes in IOP or affect the accuracy of IOP measurement, or with an inability to measure IOP were excluded. Simple random sampling was used to select participants, who were grouped by gender and age (18 to <30, 30 to <40, 40 to <50, 50 to <60, 60 to <70, and ≥70 years). Central corneal thickness and IOP at 8 to 11 o'clock in one eye of each participant were recorded. The independent sample t test and ANOVA were used for statistical analysis, and the RI of IOP values was calculated by x¯±1.96s. Results: A total of 9 310 subjects had their IOP measured, and 3 491 participants (3 491 eyes) were randomly selected from 7 886 healthy subjects. The age of the participants was (47.74±14.47) years old, ranging from 18 to 90 years old. There were 1 694 males and 1 797 females. The central corneal thickness of all participants was (525.56±49.39) μm. The daytime IOP of all participants was (15.40±2.54) mmHg (1 mmHg=0.133 kPa), and the RI was 10.42 to 20.39 mmHg. The IOP was (15.49±2.58) mmHg for males and (15.29±2.49) mmHg for females, and the gender difference was statistically significant (P<0.05). The RI of daytime IOP values was 10.43 to 20.54 mmHg for males and 10.41 to 20.18 mmHg for females. There were significant differences in daytime IOP [(15.13±2.58), (15.33±2.53), (15.49±2.50), (15.53±2.55), (15.39±2.62), and (15.28±2.52) mmHg] among 6 age groups (P<0.05). Conclusions: The distribution of daytime IOP in different gender and age groups in the eye health screening population of Handan and the RIs derived from the distribution were roughly the same as the international normal IOP RI (10 to 21 mmHg). It is recommended to refer to the RI of daytime IOP values of different genders and ages for clinical decision.

[Recompensation of complications in patients with hepatitis B virus-related decompensated cirrhosis treated with entecavir antiviral therapy]

Objective: To analyze the occurrence of recompensation conditions in patients with chronic hepatitis B virus-related decompensated cirrhosis after entecavir antiviral therapy. Methods: Patients with hepatitis B virus-related decompensated cirrhosis with ascites as the initial manifestation were prospectively enrolled. Patients who received entecavir treatment for 120 weeks and were followed up every 24 weeks (including clinical endpoint events, hematological and imaging indicators, and others) were calculated for recompensation rates according to the Baveno VII criteria. Measurement data were compared using the Student t-test or Mann-Whitney U test between groups. Categorical data were compared by the χ (2) test or Fisher's exact probability method between groups. Results: 283 of the 320 enrolled cases completed the 120-week follow-up, and 92.2% (261/283) achieved a virological response (HBV DNA 20 IU/ml). Child-Pugh and MELD scores were significantly improved after treatment (8.33 ± 1.90 vs. 5.77 ± 1.37, t = 12.70, P < 0.001; 13.37 ± 4.44 vs. 10.45 ± 4.58, t = 5.963, P < 0.001). During the 120-week follow-up period, 14 cases died, two received liver transplants, 19 developed hepatocellular cancer, 11 developed gastroesophageal variceal bleeding, and four developed hepatic encephalopathy. 60.4% (171/283) (no decompensation events occurred for 12 months) and 56.2% (159/283) (no decompensation events occurred for 12 months and improved liver function) of the patients had achieved clinical recompensation within 120 weeks. Patients with baseline MELD scores > 15 after active antiviral therapy achieved higher recompensation than patients with baseline MELD scores ≤15 [50/74 (67.6%) vs. 109/209 (52.2%), χ (2) = 5.275, P = 0.029]. Conclusion: Antiviral therapy can significantly improve the prognosis of patients with hepatitis B virus-related decompensated cirrhosis. The majority of patients (56.2%) had achieved recompensation. Patients with severe disease did not have a lower probability of recompensation at baseline than other patients.

Lactobacillus coryniformis subsp. torquens inhibits bone loss in obese mice via modification of the gut microbiota

High-fat diet (HFD)-induced obesity results in bone loss associated with an imbalanced gut microbiota and altered immune status. Probiotics are live microorganisms that are beneficial to the host and are important in maintaining bone health and gut homeostasis. In this study, the probiotic Lactobacillus coryniformis subsp. torquens (T3L) was isolated from traditional yak milk cheese produced in Lhasa and showed distinct acid and bile salt resistance as potential probiotics. Our data indicated that T3L not only reversed HFD-induced gut dysbiosis, as indicated by decreased Firmicutes-to-Bacteroidetes ratios but also reduced bone loss. The anti-obesity, microbiome-modulating, and bone-protective effects were transmissible via horizontal faeces transfer from T3L-treated mice to HFD-fed mice. The protective effects of T3L on bone mass were associated with regulatory T (Treg) cell-mediated inhibition of osteoclast differentiation. Our data indicate that T3L is a regulator of the gut microbiota and bone homeostasis in an animal model.

[Effects of Aeration on Surface Water Nutrient Dynamics and Greenhouse Gas Emission in Different Straw Returning Paddy Fields]

Straw returning is of great significance for improving soil structure, soil fertility, crop yield, and quality. However, straw returning causes environmental problems such as increased methane emission and non-point source pollutant emission risk. How to reduce the negative effects of straw returning is an urgent problem to be solved.In this study, the effects of aerobic treatment on carbon and nitrogen concentration in surface water and greenhouse gas emissions in paddy fields with different treatments of straw returning were systematically compared.The results showed that different treatments of straw returning significantly increased chemical oxygen demand (COD) in the surface water of the paddy field and significantly promoted the methane emission of the rice field and the global warming potential (GWP), although it slightly reduced N₂O emission. The increasing trends showed that wheat straw returning>rape straw>broad bean straw returning.Straw returning increased rice yield when compared with the control without straw returning, but the difference was not significant. Aerobic treatment reduced the COD in surface water by 15%-32%, the methane emission of the paddy field by 10.4%-24.8%, and the GWP of paddy field by 9.7%-24.4% under different straw returning treatments, without affecting the rice yield. The mitigation effect of aerobic treatment with wheat straw returning was the best. The results indicated the potential of oxygenation measures in greenhouse gas emission mitigation and COD emission risk reduction in straw returning paddy fields, especially in wheat straw returning paddy fields.

[Analysis of the clinical predictive value of lactate on the prognosis of patients with acute-on-chronic liver failure combined with infection]

Objective: To explore the predictive value of lactic acid for the adverse prognostic outcomes in patients with acute-on-chronic liver failure combined with infection. Methods: A retrospective analysis was conducted on the clinical data of 208 cases of ACLF combined with infection who were hospitalized from January 2014 to March 2016. Patients were divided into a survival group (n = 83) and a mortality group (n = 125) according to the results of a 90-day follow-up. The clinical data were statistically analyzed between the two groups. Multivariate logistic regression with two categorical variables was used to analyze the independent risk factors for 90-day disease mortality and establish a new prediction model. The receiver operating characteristic curve (ROC curve) was used to evaluate the predictive value of lactic acid, the MELD score, the MELD-Na score, lactic acid combined with the MELD score, lactic acid combined with the MELD-Na score, and the new model. Results: The 90-day mortality rate of 208 cases of ACLF combined with infection was 60.1%. There were statistically significant differences in white blood cell count, neutrophil count, total bilirubin (TBil), serum creatinine (Cr), blood urea nitrogen (BUN), blood ammonia, the international normalized ratio (INR), lactic acid (LAC), procalcitonin, the MELD score, the MELD-Na score, hepatic encephalopathy (HE), acute kidney injury (AKI), and bleeding between the two groups. Multivariate logistic regression analysis showed that TBil, INR, LAC, HE, and bleeding were independent risk factors for 90-day mortality in patients with ACLF combined with infection. After the establishment of MELD-LAC, MELD-Na-LAC, and a new prediction model, the ROC curve revealed that the AUC (95% confidence interval) of MELD-LAC and MELD-Na LAC were 0.819 (0.759 ~ 0.870) and 0.838 (0.780 ~ 0.886), respectively, and was superior than the MELD score [0.766 (0.702 ~ 0.823)] and MELD-Na score [0.788 (0.726 ~ 0.843)], with P < 0.05, while the new model had an AUC of 0.924, the sensitivity of 83.9%, specificity of 89.9%, and accuracy of 87.8%, which was higher than LAC, MELD score, MELD-Na score, MELD-LAC, and MELD-Na-LAC (P < 0.01). Conclusion: Lactic acid is an independent risk factor for mortality in patients with ACLF combined with infection, and it improves the clinical predictive value of MELD and MELD-Na for the prognosis of mortality.

[Investigation on status of dyslipidemia in Chinese females aged 35 years or above]

Objective: To investigate the prevalence, awareness, treatment and control status of dyslipidemia among females aged ≥35 years old across China. Methods: Participants were selected by stratified multistage random sampling method in the "Twelfth Five-Year Plan" National Science and Technology Support Project "Survey on the Prevalence of Important Cardiovascular Diseases and Key Technology Research in China" project. This study is a retrospective, cross-sectional study. A total of 17 418 females aged 35 years and over were included in the current study. The basic information such as age, medical history and menopause was collected by questionnaire. The blood lipid parameters were derived from clinical laboratory examinations. The prevalence of dyslipidemia and the rate of awareness, treatment, and control of dyslipidemia were analyzed in females aged 35 years and over. Results: The age of participants was (56.2±13.0) years old, and the prevalence of dyslipidemia was 33.1% (5 765/17 418). The prevalence rates of high total cholesterol, hypertriglyceridemia, low HDL-C and high LDL-C were 9.7% (1 695/17 418), 11.1% (1 925/17 418), 10.9% (1 889/17 418) and 7.3% (1 262/17 418), respectively. The prevalence of dyslipidemia increased with age and the prevalence of dyslipidemia in women who were not married, Han, menarche age>16 years, obesity, central obesity, alcohol consumption, diabetes, hypertension and family history of cardiovascular disease were higher than those without such characteristics (P<0.05). There were 10 432 (59.9%) menopausal females in this cohort and prevalence of dyslipidemia of these participants was 38.8% (4 048/10 432), which was higher than that of non-postmenopausal females (24.6%, 1 717/6 986) (P<0.05). The awareness rates, treatment rates and control rates of dyslipidemia were 33.9% (1 953/5 765), 15.1% (870/5 765) and 2.5% (143/5 765) respectively among females aged 35 years and over in China. Conclusion: The prevalence of dyslipidemia in Chinese females aged 35 years and over is high, and its awareness, treatment, and control rates need to be optimized.

Altered Neural Reactivity in Adolescents With Nonsuicidal Self-Injury During Exposure to Self-Injury Related Cues: Electrophysiological Evidence From a Two-Choice Oddball Paradigm

BACKGROUND

Nonsuicidal self-injury (NSSI) may be a type of addiction, that is characterized by cue reactivity. We aimed to explore the behavioral performance and neural reactivity during exposure to self-injury cues in adolescents with NSSI and major depressive disorder (MDD).

METHODS

Eighteen MDD patients, 18 MDD patients with NSSI, and 19 healthy controls (HC) were recruited to perform a two-choice oddball paradigm. All subjects were 12-18 years old. Neutral cues and self-injury related cues separately served as deviant stimuli. Difference waves in N2 and P3 (N2d and P3d) were derived from deviant waves minus standard waves. Accuracy cost and reaction time (RT) cost were used as behavioral indexes, while the N2d and P3d were used as electrophysiological indexes; the N2d reflects early conflict detection, and the P3d reflects the process of response inhibition.

RESULTS

No significant main effects of group or cue or an effect of their interaction were observed on accuracy cost and P3d latency. For RT cost, N2d amplitude, and N2d latency, there was a significant main effect of cue. For P3d amplitude, there was a significant main effect of cue and a significant group × cue interaction. In the NSSI group, the P3d amplitude with self-injury cues was significantly larger than that with neutral cues. However, there was no such effect in the MDD and HC groups.

CONCLUSIONS

Adolescents with NSSI showed altered neural reactivity during exposure to self-injury cue. Further studies with larger sample sizes are needed to confirm our results.

[Navigation-guided nasal endoscopy for removal of the cavernous hemangioma of the orbital apex through the sphenoid approach]

Objective: To explore the feasibility of navigation-guided nasal endoscopy for removal of the cavernous hemangioma of the orbital apex through the sphenoid approach. Methods: Retrospective case series study. From May 2012 to December 2019, 12 patients (12 eyes) with imaging findings of cavernous hemangioma in the orbital apex were collected at the Eye Hospital Affiliated to Nanchang University, including 3 males and 9 females aged 32 to 59 years. All patients underwent navigation-guided sinusoscopy through the sphenoid approach to remove the cavernous hemangioma of the orbital apex (video attached). Changes of visual function and complications after operation were analyzed. Results: In 3 patients without visual impairment, the postoperative visual function was still normal. Among the remaining 9 patients with preoperative visual impairment, visual function was fully recovered in 3 patients after operation, was improved in 2 patients, and had no change in 4 patients. There were no complications in 3 of the 12 patients, and 9 patients had transient, mildly limited intraocular rotation with diplopia after operation, which all returned to normal within 1 month. Conclusion: Navigation-guided sinus endoscopy through the sphenoid approach is effective and feasible in the removal of the cavernous hemangioma of the orbital apex. (Chin J Ophthalmol, 2021, 57: 837-843).

[Resting-state functional magnetic resonance imaging analysis of abnormal directional functional connectivity of the nucleus accumbens in patients with chronic tinnitus]

Objective: To investigate abnormal directional functional connectivity of the nucleus accumbens (NAc) in chronic tinnitus patients using resting-state functional magnetic resonance imaging (fMRI), and to determine the relationship between the degree of this connectivity and tinnitus characteristics. Methods: The resting-state fMRI data of 40 patients with bilateral chronic tinnitus (12 males and 28 females, aged from 26 to 63(50.6±11.6) years) and 40 healthy controls with normal hearing (16 males and 24 females, aged from 26 to 70(45.9±12.4)years) were retrospectively enrolled from the Department of Otolaryngology, Nanjing First Hospital from January 2017 to January 2020. The bilateral NAc were selected as seeds to detect the directional functional connectivity with the whole brain, then the effective connectivity values between the two groups were compared using Granger Causality Analysis (GCA), and the correlation between the effective connectivity and the characteristics of tinnitus was calculated. Results: Compared with healthy controls, the effective connectivity from the left NAc to left middle frontal gyrus in patients with bilateral chronic tinnitus was increased [(1.0±0.2)vs(0.6±0.3)], the effective connectivity from the right NAc to left inferior frontal gyrus was enhanced [(0.9±0.3)vs(0.6±0.4)], the effective connectivity from the right middle temporal gyrus to left NAc was enhanced [(1.0±0.2)vs(0.5±0.3)], the effective connectivity from the right middle frontal gyrus to right NAc was also enhanced[(1.0±0.2)vs(0.5±0.3)](all P<0.05). After adjusting for age, gender, education level, and gray matter volume, positive correlations was observed between the Tinnitus Handicap Questionnaire (THQ) scores and increased effective connectivity values from the left NAc to the left middle frontal gyrus (r=0.386, P=0.020). Additionally, enhanced effective connectivity values from the right middle frontal gyrus to the right NAc was also positively associated with tinnitus duration (r=0.390, P=0.019). Conclusion: The directional functional connectivity between the NAc and prefrontal cortex in patients with chronic tinnitus is enhanced.

[Effects and mechanism of mitochondrial transcription factor A and cytochrome c oxidase pathway in the energy production of hypoxic cardiomyocytes of rats regulated by tumor necrosis factor receptor associated protein 1]

Objective: To investigate the effects and mechanism of mitochondrial transcription factor A (TFAM) and cytochrome c oxidase (COX) pathway in the energy production of hypoxic cardiomyocytes of rats regulated by tumor necrosis factor receptor associated protein 1 (TRAP1). Methods: The cardiomyocytes were isolated from 135 neonatal Sprague-Dawley rats (aged 1-3 d) and cultured for the following experiments. (1) Cells were collected and divided into normoxia blank control (NBC) group, hypoxia blank control (HBC) group, hypoxia+ TRAP1 over-expression control (HTOC) group, and hypoxia+ TRAP1 over-expression (HTO) group according to the random number table (the same grouping method below), with 1 bottle in each group. Cells in NBC group were cultured routinely, cells in HBC group were cultured in hypoxic condition for 6 hours after routine culture, cells in HTOC and HTO groups were respectively added with TRAP1 over-expression empty virus vector and TRAP1 over-expression adenovirus vector virus suspension for transfection for 48 hours after routine culture and then cultured in hypoxic condition for 6 hours. The protein expression of TFAM of cells in each group was detected by Western blotting. (2) Cells were collected and divided into NBC, HBC, HTOC, HTO, HTO+ TFAM interference control (HTOTIC), and HTO+ TFAM interference (HTOTI) groups, with 1 well in each group. Cells in the former 4 groups were dealt with the same methods as the corresponding groups in experiment (1). Cells in HTOTIC and HTOTI groups were respectively added with TFAM interference empty virus vector and TFAM interference adenovirus vector virus suspension for transfection for 48 hours, and the other processing methods were the same as those in HTO group. The content of ATP of cells in each group was determined by ATP determination kit and microplate reader, and the COX activity of cells in each group was determined by COX activity assay kit and microplate reader. (3) Cells were collected and divided into NBC group, normoxia+ sodium azide (NSA) group, HBC group, and hypoxia+ sodium azide (HSA) group, with 1 well in each group. Cells in NBC and HBC groups were respectively dealt with the same methods as the corresponding groups in experiment (1). Cells in NSA and HSA groups were respectively added with 32 nmol sodium azide at 30 min before experiment or hypoxia, and then cells in HSA group were cultured in hypoxic condition for 6 hours. The content of ATP was determined by the same method as above. The above three experiments were repeated for three times. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: (1) Compared with that in NBC group, the protein expression of TFAM of cells in HBC group was significantly decreased (P<0.01). Compared with that in HBC group or HTOC group, the protein expression of TFAM of cells in HTO group was significantly increased (P<0.01). (2) Compared with 0.552±0.041 and 1.99±0.15 in NBC group, the COX activity (0.270±0.044) and ATP content (1.09±0.11) of cells in HBC group were significantly decreased (P<0.01). Compared with 0.269±0.042 and 1.17±0.12 in HBC group and those in HTOC group, the COX activity (0.412±0.032 and 0.404±0.016) and ATP content (1.75±0.06 and 1.69±0.07) of cells in HTO and HTOTIC groups were significantly increased (P<0.01). Compared with those in HTO and HTOTIC groups, the COX activity (0.261±0.036) and ATP content (1.23±0.07) of cells in HTOTI group were significantly decreased (P<0.01). (3) Compared with that in NBC group, the ATP content of cells in NSA and NBC groups was significantly decreased (P<0.01). Compared with that in HBC group, the ATP content of cells in HSA group was significantly decreased (P<0.01). Conclusions: TRAP1 can increase the COX activity of cardiomyocytes by raising the expression of TFAM, and finally alleviate the impairment in energy production of cardiomyocytes caused by hypoxia.

Nitrogen balance of very preterm infants with extrauterine growth restriction

Wu R, Li LH, Tian ZF, Xu WY, Hu JH, Liu YY. Nitrogen balance of very preterm infants with extrauterine growth restriction. Turk J Pediatr 2019; 61: 352-358. The aim of this study was to investigate the changes of nitrogen balance in preterm infants with extrauterine growth restriction (EUGR) during hospitalization. A total of 64 very preterm infants admitted to the Neonatal Medical Center of Huai`an Maternity and Child Healthcare Hospital were enrolled from May to October 2014. These infants had gestational ages less than 32 weeks and were within 24 hours after birth. The enrolled infants were classified into EUGR (n=18) and non EUGR (n=46) groups according to the discharge weight being below or above the 10th percentile of the expected intrauterine growth for the postmenstrual age. The urinary urea nitrogen of the infants were assayed by the Kjeldahl method and determined at 1st, 7th, 14th and 28th day after birth. Nitrogen balance at each time point was calculated and compared between the EUGR and non EUGR groups. The incidence rate of small for gestational age (SGA) infants (33.3% vs 0.0%) in the EUGR group was higher than that in non EUGR group. The difference was statistically significant (p < 0.05). The birth weight (1.37±0.20 vs 1.63±0.27) and birth weight Z-score (-1.14±0.29 vs-0.37±0.66) in the EUGR group were lower those in non EUGR group. The difference was statistically significant (all p < 0.05). At the 1st, 7th, 14th and 28th day after birth, nitrogen balance values of all infants were negative, showing an upward trend with age. At each observation time point, the nitrogen balance values in the EUGR group were lower than those in non-EUGR group. The differences on the 1st and 28th day between two groups were statistically significant (both p < 0.05), while those on the other time point were not statistically significant (both p > 0.05). All very preterm infants of study were in negative nitrogen balance while the infants of EUGR group had more seriously negative balance.

[Clinical characteristics of infection-induced acute renal injury in acute-on-chronic liver failure]

Objective: To investigate the incidence rate, influencing factors and prognosis of infection-induced acute renal injury (AKI) in patients with acute-on-chronic liver failure (ACLF). Methods: 516 cases with acute-on-chronic liver failure complicated with infection that were hospitalized in our hospital during 2014 to 2016 were retrospectively studied. General conditions and clinical characteristics of the patients were collected, and grouped according to the presence or absence of incidence and severity of AKI. General conditions, laboratory results, occurrence of complications and survival were compared and analyzed. Results: The main causes were HBV infection (67.8%) and alcoholic liver disease (20.0%). The most common sites of infection were abdominal cavity, lung and blood. Multivariate analysis showed that neutrophil count, TBIL, lactate and septic shock were independent risk factors for infection-induced AKI in ACLF patients. The cumulative mortality in patients with AKI after infection at 28, 90 and 360 days was significantly higher than those without AKI (51.6% and 20.5%, 70.2% and 40.3%, 73.4% and 45.9%; P < 0.01). In both groups, deaths had occurred mainly in the early (0 ~ 28 d) and middle (29 ~ 90 d) stage of follow-up period. In the late follow-up period (91-360 d), there was no statistically significant difference in mortality rate between the two groups. Conclusion: Infection is an important inducing cause of AKI in ACLF patients. The underlying liver disease and the severity of infection are significantly related to the infection-induced AKI in ACLF patients, and once AKI occurs after infection, the mortality rate of the patients is significantly increased.

[Effects of clinical medicine on salt sensitivity hypertension: a systematic review and meta-analysis]

Objective: To assess the effects of clinical medicine on salt sensitive hypertension. Methods: The PubMed, EMBASE, Cochrane Library, CBM, WanFang Data, VIP and CNKI databases were searched to collect randomized controlled trials (RCTs) on clinical medicine in treating salt sensitive hypertension from inception to December 2018. Two reviewers independently screened the literature, extracted data, and another investigator assessed the risk of bias included in the study. Then meta-analysis was performed using RevMan 5.3 software. Results: A total of 16 RCTs studies involving 1 355 patients were included. Meta-analysis showed that angiotensin-converting enzyme inhibitors (ACEIs) combined with diuretics could effectively reduce 24 h systolic blood pressure variability [mean difference (MD)=4.45, 95%CI: 3.47-5.43, P<0.001] and 24 h diastolic blood pressure variability (MD=3.71, 95%CI:2.83-4.59, P<0.001) in salt-sensitive hypertension patients. Angiotensin Ⅱ receptor antagonists (ARBs) combined with diuretics had no antihypertensive effect on salt-sensitive hypertension patients. Indapamide alone can reduce systolic blood pressure (MD=-14.70, 95%CI:-18.57--10.83, P<0.001) and diastolic blood pressure (MD=-8.73, 95%CI:-11.57--5.89, P<0.001). The use of ACEIs alone in salt-sensitive hypertension patients can not reduce systolic pressure (MD=2.20, 95%CI:-1.48-5.88, P=0.240) and diastolic pressure (MD=2.95, 95%CI: 1.37~4.54, P<0.001). Amlodipine combined with metformin had therapeutic effect on salt-sensitive hypertension (RR=1.23, 95%CI: 1.14~1.33, P<0.001). Conclusions: ACEIs combined with diuretics can effectively reduce blood pressure variability in salt-sensitive hypertensive patients. The use of amlodipine in combination with metformin and indapamide alone have antihypertensive effect in salt-sensitive hypertensive patients.

[Effects of glutamine on skeletal muscle membrane repair in severely burned mice and the functional mechanism]

Objective: To observe how glutamine affect the skeletal muscle membrane repair in severely burned mice through promoting the mitsugumin 53 (MG53) dimerization in skeletal muscle and to explore its functional mechanism. Methods: (1) Animal experiments. A total of 179 BALB/c male mice aged 6 to 8 weeks were divided into sham injury group (n=43), burn group (n=73) and burn+ glutamine group (n=63) according to the random number table (the same grouping method below). Mice in sham injury group were sham injured on the back, and mice in burn group and burn+ glutamine group were inflicted with 30% total body surface area full-thickness scald (hereinafter referred to as burn) on the back. Mice in burn+ glutamine group were intragastrically administered with glutamine (1 mg/kg), and the other two groups were given the same amount of amino acid solution once per day for 14 days. On post burn hour 12, 10 mice from burn group were taken for preparation of burn serum, which is used in the following cell experiments. Blood samples were collected from the hearts to prepare serum from 10 mice in sham injury group immediately after burn and from 10 mice in burn group and burn+ glutamine group on post burn day (PBD) 5, 10, and 14, respectively. And then the whole gastrocnemius muscle was harvested after the mice were sacrificed. On PBD 10, the whole flexor brevis digitorum was harvested from 6 mice in the 3 groups respectively after the mice were sacrificed. On PBD 5, 10, and 14, the whole gastrocnemius muscle tissue was harvested from another 9 mice in the 3 groups respectively after the mice were sacrificed. The mass of the whole gastrocnemius muscle of mice was weighed. The total protein content of gastrocnemius muscle of mice was detected by coomassie brilliant blue method. The repair function of myolemma of flexor brevis digitorum of mice was detected by two-photon laser fiber membrane perforating. The serum content of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) of mice was determined with radioimmunoassay. The expressions of MG53 dimer and monomer in gastrocnemius of mice were determined with non-reductive electrophoresis-Western blotting. The protein expressions of endoplasmic reticulum stress sign proteins CCAAT/enhancer binding protein homologous protein (CHOP) and glucose-regulated protein 78 (GRP78) in gastrocnemius of mice were determined with Western blotting. (2) Cell experiments. Mice skeletal muscle precursor cells C2C12 were cultured in vitro, and cells of the second passage were selected for the experiments. The cells were divided into normal control group, burn serum group, and burn serum+ glutamine group, with 3 dishes in each group and 1×10(3) cells in each dish. Cells in normal control group were cultured with 1 mL Dulbecco's modified Eagle medium (DMEM) with fetal bovine serum of volume fraction 10%, cells in burn serum group were cultured with 1 mL DMEM with burn serum of volume fraction 10%, and cells in burn serum+ glutamine group were cultured with 1 mL DMEM with burn serum of volume fraction 10% and 4 μL glutamine with a final molar concentration of 8 mmol/L. After 24 hours of culturing, the repair function of myocyte membrane after differentiation of skeletal muscle precursor cells in mice was detected with the same method before. Another cells were grouped and cultured as before, with 3 wells in each group and 1×10(5) cells in each well. After 24 hours of culturing, the expressions of MG53 dimer and monomer and endoplasmic reticulum stress marker proteins in the cells were detected as before. Data were processed with analysis of variance of factorial design, one-way analysis of variance, least significant difference t test, and Student Newman Keuls test. Results: Animal experiments. (1) Compared with those in sham injury group, the mass and total protein content of gastrocnemius muscle of mice in burn group were significantly decreased on PBD 5, 10, and 14 (P<0.05). Compared with those in burn group, the mass and total protein content of gastrocnemius muscle of mice in burn+ glutamine group were significantly increased on PBD 5, 10, and 14 (P<0.05). (2) Compared with that in sham injury group (0.9±0.4), the fluorescence intensity of FM1-43 in myofiber of mice in burn group (7.8±0.4) was significantly increased on PBD 10 (t=7.75, P<0.05). Compared with that in burn group, the fluorescence intensity of FM1-43 in myofiber of mice in burn+ glutamine group (4.0±0.4) was significantly decreased on PBD 10 (t=-4.31, P<0.05). (3) Compared with that in sham injury group, the serum content of TNF-α and IL-6 of mice in burn group was significantly increased on PBD 5, 10, and 14 (P<0.05). Compared with that in burn group, the serum content of TNF-α and IL-6 of mice in burn+ glutamine group was significantly decreased on PBD 5, 10, and 14 (P<0.05). (4) Compared with 56.97±2.82, 44.89±4.72, 42.46±1.06, 14.26±0.99, 62.36±2.74, and 29.45±0.84 in sham injury group, the expressions of MG53 dimer and monomer in gastrocnemius of mice were significantly decreased in burn group on PBD 5, 10, and 14 (6.16±0.25, 26.09±1.22, 28.86±1.53, 5.63±0.25, 26.74±0.79, 4.41±0.52, P<0.05). Compared with those in burn group, the expression of MG53 dimer of gastrocnemius of mice in burn+ glutamine group was significantly increased on PBD 10 and 14 (36.79±1.44, 43.96±1.62), and the expression of MG53 monomer of gastrocnemius muscle of mice in burn+ glutamine group was significantly increased on PBD 14 (13.16±2.17, P<0.05). Compared with those in sham injury group, the protein expressions of CHOP and GRP78 in gastrocnemius muscle of mice in burn group were significantly elevated on PBD 5, 10, and 14 (P<0.05). Compared with those in burn group, the protein expressions of CHOP and GRP78 in gastrocnemius of mice in burn+ glutamine group were significantly reduced on PBD 5, 10 (P<0.05). Cell experiments. (1) Compared with that in normal control group (1.76±0.25), the fluorescence intensity of FM1-43 in cells in burn serum group (9.46±1.22) was significantly increased after 24 hours of culturing (t=12.28, P<0.05). Compared with that in burn serum group, the fluorescence intensity of FM1-43 in cells in burn serum+ glutamine group (4.71±0.45) was significantly decreased after 24 hours of culturing (t=-7.59, P<0.05). (2) The expressions of MG53 monomer of cells were similar in normal control group, burn serum group, and burn+ glutamine group after 24 hours of culturing (P>0.05). Compared with 58.5±1.8 in normal control group, the expression of MG53 dimer of cells in burn serum group was significantly decreased after 24 hours of culturing (14.1±1.4, P<0.05). Compared with that in burn serum group, the expression of MG53 dimer of cells in burn serum+ glutamine group was significantly increased after 24 hours of culturing (30.9±0.6, P<0.05). Compared with those in normal control group, the protein expressions of CHOP and GRP78 of cells were significantly elevated in burn serum group after 24 hours of culturing (P<0.05). Compared with those in burn serum group, the protein expressions of CHOP and GRP78 of cells were significantly reduced in burn serum+ glutamine group after 24 hours of culturing (P<0.05). Conclusions: Glutamine can promote MG53 dimerization by alleviating endoplasmic reticulum stress in severely burned mice. Thus it can accelerate skeletal muscle membrane repair, reduce the local inflammatory reaction of skeletal muscle and consumption of skeletal muscle.

Exogenous substances regulate silkworm fat body protein synthesis through MAPK and PI3K/Akt signaling pathways

Insect fat body is an important intermediate metabolic organ that plays an important role in protein metabolism and detoxification. In order to study the effects of TiO₂ NPs and phoxim on fat body protein synthesis through MAPK and PI3K/Akt signaling pathways in silkworms, we determined the effects of TiO₂ NPs and phoxim, alone and in combination, on fat body protein content of silkworms, analyzed the gene expression profile of the fat body, and verified the expression of characteristic genes. We found that TiO₂ NPs and phoxim alone increased the total protein content of the fat body, and up-regulated MAPK and PI3K/Akt signaling pathway genes. TiO₂ NPs up-regulated the expression of two growth and development-related genes-insulin-like peptide and neuropeptide receptor B-by 5.17 and 3.89-fold, respectively. Phoxim up-regulated the expression of detoxification genes-P450, GST, and CarE2. Pretreatment with TiO₂ NPs could reduce phoxim-increased total protein content and up-regulated MAPK and PI3K/Akt signaling pathway genes and detoxification genes; the activities of detoxification enzymes were consistent with the gene expression pattern. Our results showed that MAPK and PI3K/Akt signaling pathways both regulate fat body protein synthesis in silkworms, but the target proteins induced to express were different under different inducing factors. Our finding may provide a reference for investigating the mechanism of protein synthesis regulation through MAPK and PI3K/Akt signaling pathways.

293FT is a highly suitable mammalian cell line for the in vitro enzymatic activity analysis of typical P450 proteins

Mammalian cells have been widely used for the in vitro evaluation of the functional effect of allelic variants of cytochrome P450 (CYP). The aim of this study was to determine the most suitable mammalian cell line for the in vitro drug metabolism analysis of CYP variants. Three reported cell lines (COS-7, HepG2, 293T) and one fast-growing variant of the 293 cell line 293FT were transfected with vectors expressing green fluorescent protein or typical variants of CYP2C9, CYP2C19 or CYP2D6 to investigate the protein expression levels and the catalytic activity of expressed CYP allelic variants. The transfected 293FT cells had the highest protein expression level and exhibited the highest enzymatic activity, while HepG2 cells showed the lowest activity among the four tested cell lines. Simultaneously, 293FT cells still maintained the similar relative enzymatic ratio among three typical CYP2C9 variants to that of the commonly used COS-7 cells. In addition, 293FT cells could also be used for the in vitro functional evaluation of two other typical P450 proteins, CYP2C19 and CYP2D6. Therefore, the 293FT cell line is more suitable for the in vitro enzymatic activity analysis of typical P450 proteins than any other reported mammalian cell lines.

Influence of fluoride additions on biological and mechanical properties of Na2O-CaO-SiO2-P2O5 glass-ceramics

Two series of Na2O-CaO-SiO2-P2O5 glass-ceramics doped with NH4HF2 (G-NH4HF2) or CaF2 (G-CaF2) have been prepared by sol-gel method. The glass-ceramic phase composition and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS). The mechanical properties and thermal expansion coefficient were measured by a microhardness tester, an electronic tensile machine and a thermal expansion coefficient tester. The structure difference between these two glass-ceramics was investigated by Fourier transform infrared spectroscopy (FTIR), and the in vitro bioactivity of the glass-ceramics was determined by in vitro simulated body fluid (SBF) immersion test. The hemolysis test, in vitro cytotoxicity test, systemic toxicity test and the implanted experiment in animals were used to evaluate the biocompatibility of the glass-ceramics. The mechanical properties of sample G-NH4HF2 are lower than that of sample G-CaF2, and the bioactivity of sample G-NH4HF2 is better than that of sample G-CaF2. The thermal expansion coefficients of these two glass-ceramics are all closer to that of Ti6Al4V. After 7 days of SBF immersion, apatites were induced on glass-ceramic surface, indicating that the glass-ceramics have bioactivity. The hemolysis test, in vitro cytotoxicity test and systemic toxicity test demonstrate that the glass-ceramics do not cause hemolysis reaction, and have no toxicity to cell and living animal. The implanted experiment in animals shows that bone tissue can form a good osseointegration with the implant after implantation for two months, indicating that the glass-ceramics are safe to serve as implants.

Opportunistic posttransplantation virus infections in renal transplant recipients

BACKGROUND

Opportunistic virus infection is one of the most common complications in renal transplant (RT) recipients. Cytomegalovirus (CMV) and BK virus (BKV) are important pathogens and each of these infections affects the other. In contrast, there is only limited information on JC virus (JCV) infection and its relation to CMV infection in RT recipients. This prospective study investigated the rates of JCV and CMV infections and their risk factors and correlations.

METHODS

We studied 52 RT recipients. JCV and CMV were detected using nested qualitative polymerase chain reaction assays of urine. The clinical characteristics of JCV and CMV infection were compared and risk factors analyzed with the use of binary logistic regression.

RESULTS

JCV and CMV were detected in 40.4% and 34.6% of the RT recipients, respectively. Cyclosporine (CsA) was a risk factor for both JCV and CMV infection (odds ratio [OR] 7.187; P=.002; OR 4.182; P=.021); CMV infection was a risk factor for JCV infection (OR 3.900; P=.039).

CONCLUSIONS

JCV and CMV infections are common in RT recipients. CsA is a risk factor for both JCV and CMV infection. JCV infection is related to CMV infection.

Anomalous line shape of the cross section for e{+}e{-}--> hadrons in the center-of-mass energy region between 3.650 and 3.872 GeV

We observe an obvious anomalous line shape of the e;{+}e;{-}--> hadrons total cross sections in the energy region between 3.700 and 3.872 GeV. It is inconsistent with the explanation for only one simple psi(3770) resonance with a statistical significance of 7sigma. The anomalous line shape may be explained by two possible enhancements of the inclusive hadron production near the center-of-mass energies of 3.764 and 3.779 GeV, indicating that either there is likely a new structure in addition to the psi(3770) resonance around 3.773 GeV, or there are some physics effects reflecting the DD[over ] production dynamics.

Search for the invisible decay of J/psi in psi(2S) --> pi(+)pi(-) J/psi

Using psi(2S) --> pi(+)pi(-) J/psi events in a sample of 14.0 x 10(6) psi(2S) decays collected with the BES-II detector, a search for the decay of the J/psi to invisible final states is performed. No signal is found, and an upper limit at the 90% confidence level is determined to be 1.2 x 10(-2) for the ratio B(J/psi --> invisible)/B(J/psi-->mu(+)mu(-)). This is the first search for J/psi decays to invisible final states.

Measurement of psi2S radiative decays

Using 14 x 10(6) psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gammapp, gamma2(pi+pi-), gammaKS0K+pi-+c.c., gammaK+K-pi+pi-, gammaK*0K-pi++c.c., gammaK*0K*0, gammapi+pi-pp, gamma2(K+K-), gamma3(pi+pi-), and gamma2(pi+pi-)K+K- with the invariant mass of hadrons below 2.9 GeV/c2. We also report branching fractions of psi(2S) decays into 2(pi+pi-)pi0, omegapi+pi-, omegaf2(1270), b1+/-pi-/+, and pi02(pi+pi-)K+K-.

Toxicity and protective efficiency of cryoprotectants to flounder (Paralichthys olivaceus) embryos

With the purpose of finding an ideal cryoprotectant or combination of cryoprotectants in a suitable concentration for flounder (Paralichthys olivaceus) embryo cryopreservation, we tested the toxicities, at culture temperature (16 degrees C), of five most commonly used cryoprotectants-dimethyl sulfoxide (Me2SO), glycerol, methanol (MeOH), 1,2-propylene glycol (PG) and ethylene glycol (EG). In addition, cryoprotective efficiency to flounder embryos of individual and combined cryoprotectants were tested at -15 degrees C for 60 min. Five different concentrations of each of the five cryoprotectants and 20 different combinations of these cryoprotectants were tested for their protective efficiency. The results showed that the toxicity to flounder embryos of the five cryoprotectants are in the following sequence: PG < MeOH < Me2SO < glycerol < EG (P < 0.05); whereas the protective efficiency of each cryoprotectant, at -15 degrees C for a period of 60 min, are in the following sequence: PG > Me2SO approximately MeOH approximately glycerol > EG (greater symbols mean P < 0.05, and approximate symbols mean P > 0.05). Methanol combined with any one of the other cryoprotectants gave the best protection, while ethylene glycol combined with any one of the other cryoprotectants gave the poorest protection at -15 degrees C. Toxicity effect was concentration dependent with the lowest concentration being the least toxic for all five cryoprotectants at 16 degrees C. For PG, MeOH and glycerol, 20% solutions gave the best protection at -15 degrees C; whereas a 15% solution of Me2SO, and a 10% solution of EG, gave the best protection at -15 degrees C.

Increased phospho-adducin immunoreactivity in a murine model of amyotrophic lateral sclerosis

Adducins alpha, beta and gamma are proteins that link spectrin and actin in the regulation of cytoskeletal architecture and are substrates for protein kinase C and other signaling molecules. Previous studies have shown that expressions of phosphorylated adducin (phospho-adducin) and protein kinase C are increased in spinal cord tissue from patients who died with amyotrophic lateral sclerosis, a neurodegenerative disorder of motoneurons and other cells. However, the distribution of phospho-adducin immunoreactivity has not been described in the mammalian spinal cord. We have evaluated the distribution of immunoreactivity to serine/threonine-dependent phospho-adducin at a region corresponding to the myristoylated alanine-rich C kinase substrate-related domain of adducin in spinal cords of mice over-expressing mutant human superoxide dismutase, an animal model of amyotrophic lateral sclerosis, and in control littermates. We find phospho-adducin immunoreactivity in control spinal cord in ependymal cells surrounding the central canal, neurons and astrocytes. Phospho-adducin immunoreactivity is localized to the cell bodies, dendrites and axons of some motoneurons, as well as to astrocytes in the gray and white matter. Spinal cords of mutant human superoxide dismutase mice having motoneuron loss exhibit significantly increased phospho-adducin immunoreactivity in ventral and dorsal horn spinal cord regions, but not in ependyma surrounding the central canal, compared with control animals. Increased phospho-adducin immunoreactivity localizes predominantly to astrocytes and likely increases as a consequence of the astrogliosis that occurs in the mutant human superoxide dismutase mouse with disease progression. These findings demonstrate increased immunoreactivity against phosphorylated adducin at the myristoylated alanine-rich C kinase substrate domain in a murine model of amyotrophic lateral sclerosis. As adducin is a substrate for protein kinase C at the myristoylated alanine-rich C kinase substrate domain, the increased phospho-adducin immunoreactivity is likely a consequence of protein kinase C activation in neurons and astrocytes of the spinal cord and evidence for aberrant phosphorylation events in mutant human superoxide dismutase mice that may affect neuron survival.

Effects of short-term alendronate treatment on the three-dimensional microstructural, physical, and mechanical properties of dog trabecular bone

The bisphosphonate, alendronate, is well known for its potent inhibition of osteoclast-mediated bone resorption. It has been used clinically for the treatment of osteoporosis and has also recently been used to reduce osteolysis around prostheses in a canine revision model of implant loosening (femoral condyle). In this study, the effects of alendronate on trabecular bone properties were assessed in dogs at an oral dose of 0.5 mg/kg per day over a 12 week period, and compared with control dogs. Cubic cancellous bone specimens were produced from lumbar vertebrae (L-1 and L-2) and bilateral proximal humeri. These specimens were scanned using a high-resolution microcomputed tomography (micro-CT) system. From accurate data sets, three-dimensional microstructural properties were calculated and physical and mechanical properties were determined. Treatment with alendronate increased bone volume fraction by 9.5%, 7.7%, 7.4%, and 18.4%, respectively, in L-1, L-2, humeral greater tuberosity, and humeral head trabecular bone. In the lumbar vertebrae, the alendronate-treated trabeculae were thicker and lower in bone surface-to-volume ratio. In the greater tuberosity, the alendronate-treated trabeculae were thicker, lower in bone surface-to-volume ratio, and less anisotropic. In the humeral head, the alendronate-treated trabeculae were thicker, less anisotropic, lower in surface density, and showed decreased trabecular separation. Alendronate significantly increased apparent density and collagen density in the lumbar vertebrae and humeral heads, and significantly decreased collagen concentration in the vertebrae. In the lumbar vertebrae, Young's modulus in the cephalocaudal direction, ultimate stress, and failure energy were significantly increased in the alendronate-treated group. The changes in mechanical properties in the humeral head trabecular bone were similar to those seen in the lumbar vertebrae. Our results demonstrate that alendronate increases the mechanical properties of healthy canine trabecular bone after short-term treatment. The physical and microstructural changes of trabecular bone are consistent with the significantly increased mechanical properties.

Behavior of a PZT ring under non-uniform mechanical stress

Ring-shaped lead zirconate titanate (PZT) piezoelectric vibrators were subjected to non-uniform mechanical stress applied by bolt clamping. The effect of mechanical stress on the effective electromechanical coupling factor (k(eff)) and mechanical quality factor (Qm) of the thickness and wall thickness modes was studied by an equivalent electric circuit analysis. The initiation and propagation of cracks under mechanical stress were also discussed based on the resonance method and the indentation technique. k(eff) for both the thickness and wall thickness modes decreased with increase in mechanical stress due to de-poling of the PZT. Qm of the thickness mode dropped sharply with increase in mechanical stress while Qm of the wall thickness mode remained almost unchange. Existence of microcracks in a PZT vibrator can be detected by the occurrence of spurious vibrations at the wall thickness mode in the electrical impedance vs. frequency spectra.

[The characteristic infrared spectra of alpha,alpha'-dioxoketene cyclic dithioacetals]

The characteristic infrared spectra of the five alpha,alpha'-dioxoketene cyclic dithioacetals such as carbonyl, double bond of carbon and carbon, single bond of carbon and sulfur etc have been studied. It is specially important that the changing rules with the change of chemical structure have been discussed.

Ciprofloxacin-loaded bovine serum albumin microspheres: preparation and drug-release in vitro

Ciprofloxacin albumin microspheres were prepared by the spray drying technique, with bovine serum albumin as the natural biodegradable wall material. The spherical microspheres, flowed well, were organic solvent free and in the size range 1-5 microm. The drug release from the microspheres could be retarded by further thermal denaturation. The sustained-release microspheres were suitable for dry powder inhaled lung drug delivery systems.

[Kinetics of inactivation of calf intestine alkaline phosphatase by EDTA with absorption spectrum method]

Calf intestinal alkaline phosphatase (EC.3.1.3.1) is a dimeric metalloenzyme composed of two identical subunits, the each active site of which contains a tight cluster of two zinc ions and one magnesium ion. The kinetic theory of the substrate reaction during irreversible inhibition of enzyme activity previously described by Tsou has been applied for a study on the kinetics of the course of inactivation of the enzyme by EDTA. The kinetics of the substrate reaction with different concentrations of the substrate p-nitrophenylphosphate (PNPP) and inactivator EDTA suggested a competitive complexing mechanism for inactivation by EDTA, and the process of inactivation composed of the rapid initial formation of an enzyme-EDTA complex, in which the conformation of enzyme has been changed, and then zinc ions are finally removed from the enzyme.

Identification of GABA(B) receptor in rat testis and sperm

gamma-Aminobutyric acid (GABA) can mimic and potentiate the action of progesterone in initiating the acrosome reaction (AR) of mammalian sperm, indicating that sperm contain receptors for GABA. This contention was validated by identifying the receptor (R) subtype, GABA(A)R, in mammalian sperm. In the present study a second subtype, GABA(B)R, was identified in rat testis and sperm. Total RNAs of rat testis and sperm were prepared and used as template to synthesize the respective cDNAs by the RT-PCR method. Two splice variants of the cDNA coding GABA(B)R1 (GABA(B)R1a and GABA(B)R1c) and GABA(B)R2 were identified. Extracts of rat testis, spermatogenic cells and sperm contained two proteins with estimated molecular sizes of 130 and 100 kDa, corresponding to GABA(B)R1a and GABA(B)R1c/lb, respectively, determined by Western blot using polyclonal anti-GABA(B)R1 antibody. By an indirect immunofluorescence technique, GABA(B)R1 was located on the head of rat sperm. The present finding is the first direct demonstration that mammalian sperm contain GABA(B)R.

Overexpression of gamma-aminobutyric acid transporter subtype I leads to cognitive deterioration in transgenic mice

AIM

To explore the physiological role of gamma-aminobutyric acid transporter subtype I (GAT1) in cognition.

METHODS

Transgenic mice were produced by pronuclei microinjection method. Integration of transgene was identified by Southern-blot and PCR analysis in various generations. Level of GAT1 mRNA in a variety of tissues was evaluated by semi-quantitative RT-PCR analysis. GAT1 protein was detected by immunofluorescence and histochemistry analysis. Associative learning capacity was analyzed by conditioned avoidance task. Memory retention was assessed by novel object recognition test. Morphology of synaptosomes was examined by electron microscope.

RESULTS

Four independent founder mice bearing various copies of transgene were generated. GAT1 was evidently overexpressed at both mRNA and protein level in a variety of tissues from transgenic mice. In comparison with wild-type mice, transgenic mice exhibited significantly declined associative learning capacity (P < 0.01) and decreased memory retention (P < 0.01 in 1-h-retention, and P < 0.05 in 1-d-retention). In addition, the amount of asymmetric synapses in the brain of transgenic mice was reduced approximately by 24 %, relative to wild-type mice.

CONCLUSION

Overexpression of GAT1 in mice results in cognitive deterioration, indicating that the alteration in the expression of gamma-aminobutyric acid transporters is involved in the pathophysiological mechanism underlying some cognitive deficiencies.

Transgenic mice ubiquitously expressing human Fas ligand develop a slight form of graft-versus-host-like disease

AIM

To construct transgenic mice bearing human Fas ligand (FasL/CD95L) cDNA, and further explore the physiological effects of ubiquitous expression of FasL on such animals.

METHODS

Transgenic mice were produced by pronuclei microinjection method. Integration and transmission of transgene were identified by nest-PCR and Southern-blot analysis. Level of FasL mRNA was evaluated by semi-quantitative RT-PCR analysis. FasL protein was detected by immunofluorescence analysis. Morphological alterations in tissues were analyzed by histological examination. The percentage of alphabetaT cells in the spleen was determined by flow cytometry analysis.

RESULTS

Two independent founder mice bearing human FasL cDNA under the control of CMV promoter were generated healthily. Human FasL was moderately expressed in the majority of tissues examined in F1 heterozygotic mice. Although developing normally, adult transgenic mice exhibited a slight form of graft-versus-host (GVH)-like disease characterized by many morphological abnormalities occurring locally in the spleen, testis, lung and liver. In addition, the percentage of alphabetaT cells in the spleen was respectively decreased approximately by 32 % and 24 % in two independent transgenic lines, relative to wild-type mice.

CONCLUSION

Ubiquitous expression of Fas ligand can lead to slight GVH-like disease

Human xenoreactivity is reduced in mice bearing porcine antisense alpha(1,3) galactosyltransferase cDNA

AIM

To explore the effect of antisense alpha(1,3) galactosyltransferase alpha(1,3) GT cDNA on production of Gal alpha(1,3) Gal (Gal epitope) xenoantigen in vivo.

METHODS

Transgenic mice bearing the porcine antisense alpha(1,3) GT cDNA (nt 1alpha-640) were generated by pronuclei microinjection method. The integration of transgene was identified by PCR and Southern-blot analysis. The expression of murine alpha(1,3) GT was characterized by RT-PCR. Morphology of the spleen was examined by histological technique. Gal epitope was detected by immunofluorescent analysis. Binding of human natural xenoantibodies (IgM and IgG) and complement (C3c) to cells from mice was determined by flow cytometric assay.

RESULTS

Transgenic mice bearing the porcine antisense alpha(1,3) GT cDNA were born healthy and developed normally. However, necrosis occurred in the spleen of some mice heterozygous for transgene. Cell surface Gal epitope in transgenic heterozygotes was evidently reduced. Substantially less (30 % - 60 %) xenoantibodies in human serum bound to cells from a variety of tissues of transgenic heterozygotes compared with wild-type controls. Consequentially, human complement activation on cells from these mice was reduced by 40 % - 50 %.

CONCLUSION

Human xenoreactivity could be effectively reduced by inhibiting the expression of alpha(1,3) galactosyltransferase with an antisense gene.

Overexpression of gamma-aminobutyric acid transporter subtype I leads to susceptibility to kainic acid-induced seizure in transgenic mice

Gamma-aminobutyric acid (GABA) is the principal inhibitory neurotransmitter, and the GABAergic synaptic transmission is normally terminated by the rapid uptake through GABA transporters. With transgenic mice ubiquitously overexpressing GABA transporter subtype I (GAT1), the present study explored the pathophysiological role of GAT1 in epileptogenesis. Though displaying no spontaneous seizure activity, these mice exhibit altered electroencephalographic patterns and increased susceptibility to seizure induced by kainic acid. In addition, the GABA(A) receptor and glutamate transporters are up-regulated in transgenic mice, which perhaps reflects a compensatory or corrective change to the elevated level of GAT1. These preliminary findings support the hypothesis that excitatory and inhibitory neurotransmission, and seizure susceptibility can be altered by neurotransmitter transporters.

Transgenic mice overexpressing gamma-aminobutyric acid transporter subtype I develop obesity

Transgenic mice ubiquitously overexpressing murine gamma-aminobutyric acid transporter subtype I were created. Unexpectedly, these mice markedly exhibited heritable obesity, which features significantly increased body weight and fat deposition. Behavioral examination revealed that transgenic mice have slightly reduced spontaneous locomotive capacity and altered feeding pattern. This preliminary finding indicates that the inappropriate level of gamma-aminobutyric acid transporters may be directly or indirectly involved in the pathogenic mechanism underlying certain types of obesity.

Estimation of number of subjects required for comparison of drug versus control in adaptive designs

INTRODUCTION

Adaptive designs have often been proposed as a way of using accruing data to affect future allocation scheme in clinical trials. The goal is to assign more patients to the better treatment. To implement clinical trials efficiently, sample size must be estimated in advance. In adaptive design, it is difficult to calculate the required sample size, because the allocation probabilities keep changing during the course of the trials.

METHODS

We focus on the sample size of two-arm (drug versus control) clinical trials. Based on its asymptotic properties, a formula of calculating sample size is derived for the randomised play-the-winner rule. We also compare sample size and power between the randomised play-the-winner rule and equal allocation. Some simulation studies illustrate the operating characteristics of the designs.

RESULTS AND DISCUSSION

The required sample size of the randomised play-the-winner rule is slightly larger than that of the equal allocation design in most cases. The randomised play-the-winner rule is recommended for ethical reasons.

[Determination of elemenyl piperidine salt in water by capillary gas chromatography]

beta-Elemene and its derivatives were hopeful new antitumor drugs. A method for determination of elemenyl piperidine salt in water has been developed with capillary gas chromatography. The samples were neutralized by sodium carbonate and extracted by n-heptane. n-Octadecane was used as the internal standard. The linear range was from 10 g/L to 100 g/L, with a correlation coefficient of 0.9998. The average recovery of the method was 99.96% and the RSD was 0.46% (n = 5). The coefficient of variation was less than 2%. The method is simple, rapid, accurate and can be applied to the determination of the nitrogen-containing compounds of beta-elemene.

[Clinical application of sural nerve island flap pedicled with collateral vessels]

OBJECTIVE

To sum up the application experience of the sural nerve island flap pedicled with the collateral vessels.

METHODS

From 1997, the retrograde-flow sural nerve island flaps pedicled with collateral vessels were performed to repair the soft tissues defects of the shank in 3 cases, ankle in 3 cases and foot in 8 cases.

RESULTS

Twelve flaps were survived, one flap was partially necrosed and one flap was necrosed. Among them, 10 wounds healed by first intention, 3 cases were healed after changing dressing and the one necrosed flap was repaired by free flap transplantation. Nine cases were followed up for 3 to 21 months and had fine appearance and function. The flap texture was similar to normal skin, the sensation of flap partially recovered after 6 months.

CONCLUSION

The flap has more reliable blood supply and great rotation arc, it is easy to resect with little injury. It is excellent for repairing the soft tissues defect in the anterior leg, ankle and proximal half of foot. It is more significant while the main blood vessels are damaged.

[Identification of turtle shell, tortoise plastron and their counterfeit products]

OBJECTIVE

To identify the commercial Chinese medicines turtle shell and tortoise plastron.

METHOD

Morphological identification and differential thermal analysis (DTA).

RESULT

2 kinds of counterfeit turtle shell and 3 kinds of counterfeit tortoise plastron were found, and their morphological and DTA identification features were proposed.

CONCLUSION

Sea turtle shells presently on the market are sham commodities of turtle shell, which derive from Lissemys punctata and Pelochelys bibroni indigenous to south Asia, while plastrons of Ocadia sinensis, Chelonia mydas and Lepidochelys olivacea are counterfeit products of tortoise plastron. Turtle shells, tortoise plastrons and their counterfeit products may be exactly distinguished by morphological and DTA features.

Identification of gamma-aminobutyric acid transporter (GAT1) on the rat sperm

Some recent studies indicated that GABAergic system is involved in mammalian sperm acrosome reaction (AR), but direct evidence pertaining to the expression of gat1 in mammalian sperm is not yet demonstrated. In this study, we evaluated the presence of 67kDa GAT1 protein and mRNA in rat testis by Western blotting and reverse transcription-polymerase chain reaction. Meanwhile, immunohistochemical and immunofluorescent analyses also identified GAT1 protein on the elongated spermatid and sperm. These results indicated that rat testis is a novel site of gat1 expression. Further studies should be taken to explore the role of GAT1 protein on sperm acrosome reaction.

Gamma-aminobutyric acid transporter (GAT1) overexpression in mouse affects the testicular morphology

Gamma-aminobutyric acid and GABAergic receptors were previously reported to be distributed in reproductive systems besides CNS and predicted to participate in the modulation of testicular function. Gamma-aminobutyric acid transporter was implicated to be involved in this process. However, the potential role of gamma-aminobutyric transporter in testis has not been explored. In this study, we investigated the existence of mouse gamma-aminobutyric acid transporter subtype I (mGAT1) in testis. Wild-type and transgenic mice, which overexpressing mGAT1 in a variety of tissues, especially in testis, were primarily studied to approach the profile of mGAT1 in testis. Mice with overexpressed mGAT1 develop normally but with reduced mass and size of testis as compared with wild-type. Testicular morphology of transgenic mice exhibited overt abnormalities including focal damage of the spermatogenic epithelium accompanied by capillaries proliferation and increased diameter of seminiferous tubules lumen. Reduced number of spermatids was also found in some seminiferous tubules. Our results clearly demonstrate the presence of GAT1 in mouse testis and imply that GAT1 is possibly involved in testicular function.

Characterization of two subclasses of PR-10 transcripts in lily anthers and induction of their genes through separate signal transduction pathways

The lily PR-10 belongs to a family of intracellular pathogenesis-related (IPR) proteins. Genomic Southern analysis indicates that the PR-10 is encoded by a family of multiple genes. Seven heterogeneous cDNA clones encoding lily PR-10 from Lilium longiflorum are divided into two subclasses based on sequence comparison and Southern hybridization. A 82% overall sequence similarity was found between the two subclasses (represented by PR-10c and d). The two cDNAs include an open reading frame of 474 bp encoding 157 amino acids. 5'- and 3'-untranslated regions exhibit low similarity, but similarity is high in the coding region. The lily PR-10 genes are induced by abscisic acid (ABA) and methyl jasmonate (MeJA) in the anther and various other organs of lily plants. The induction of PR-10 genes by ABA and MeJA in lily anthers occurs by two separate signal transduction pathways. The protein phosphatase inhibitor okadaic acid inhibits the MeJA-induced expression of PR-10 genes downstream of MeJA. In addition, the protein kinase inhibitor staurosporine inhibits the MeJA-induced expression of PR-10 genes, implying that an activity of staurosporine-sensitive protein kinases exists downstream of MeJA in the anther. However, okadaic acid does not inhibit the ABA-induced expression of PR-10 genes whereas staurosporine does. These observations suggest that, in addition to the known pathway that ABA induces gene expression by activating JA or MeJA, a MeJA-independent pathway of ABA induction exists in the anther. The alternative pathway of ABA induction involves a staurosporine-sensitive protein kinase activity downstream of ABA.

[Studies on oral sustained-release microspheres of nifedipine]

Nifedipine has been incorporated into Eudragit RL microspheres by the emulsion solvent-evaporation process using an acetone/liquid paraffin system. The drug in the Eudragit RL microspheres was present in either molecular dispersion or amorphous state. The drug release profile from microspheres conformed to the Higuchi equation. The microspheres were stable under different storage conditions for six months with respect to drug content, dispersing state and release profile. The in vivo results in eight healthy volunteers showed that the relative bioavailability of the nifedipine sustained-release microspheres against commercial retard tablet as a control was 102.5%, and the microsphere formulation was bioequivalent to the retard tablet. Significant in vitro and in vivo correlation was also found for the microspheres.