[Determination of eight neonicotinoid pesticides in wastewater by solid phase extraction combined with liquid chromatography-tandem mass spectrometry].

Neonicotinoid pesticides are a relatively new class of pesticides that have garnered significant attention owing to their potential ecological risks to nontarget organisms. A method combining solid phase extraction with liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) was developed for the rapid and accurate detection of eight neonicotinoid pesticides (dinotefuran, E-nitenpyram, thiamethoxam, clothianidin, imidacloprid, imidaclothiz, acetamiprid, and thiacloprid) in wastewater. The chromatographic mobile phase and MS parameters were selected, and a single-factor method was used to determine the optimal column type, extraction volume, sample loading speed, and pH for SPE. The optimal parameters were as follows: column type, HLB column (500 mg/6 mL); sample extraction volume, 500 mL; sample loading speed, 10 mL/min; and sample pH, 6-8. The matrix effects of the wastewater samples were reduced by optimizing the chromatographic gradient-elution program, examining the dilution factor of the samples, and using the isotope internal standard calibration method. Prior to analysis, the wastewater samples were diluted 5-fold with ultrapure water for pretreatment. Subsequently, 2 mmol/L ammonium acetate aqueous solution containing 0.1% (v/v) formic acid and methanol was used as mobile phases for gradient elution on a ZORBAX Eclipse Plus C18 column (100 mm×2.1 mm, 1.8 µm). The samples were quantified using positive-ion multiple reaction monitoring (MRM) mode for 10 min. Imidacloprid-d4 was used as the isotope internal standard. The SPE process was further optimized by applying response surface methodology to select the type and mass of rinsing and elution solvents. The optimal pretreatment of the SPE column included rinsing with 10% methanol aqueous solution and elution with methanol-acetonitrile (1∶1, v/v) mixture (7 mL). The eight neonicotinoid pesticides showed satisfactory linearity within the relevant range, with linear correlation coefficients (r) all greater than 0.9990. The method detection limits (MDLs) ranged from 0.2 to 1.2 ng/L, and the method quantification limits (MQLs) ranged from 0.8 to 4.8 ng/L. The average recoveries of the eight neonicotinoid pesticides were in the range of 82.6%-94.2% at three spiked levels, with relative standard deviations (RSDs) ranging from 3.9% to 9.4%. Finally, the optimized method was successfully applied to analyze wastewater samples collected from four sewage treatment plants. The results indicated that the eight neonicotinoid pesticides could be generally detected at concentrations ranging from not detected (ND) to 256 ng/L. The developed method has a low MDL and high accuracy, rendering it a suitable choice for the trace detection of the eight neonicotinoid pesticides in wastewater when compared with other similar methods. The proposed method can be utilized to monitor the environmental impact and assess the potential risks of neonicotinoid pesticides in wastewater, thus promoting the protection of nontarget organisms and the sustainable use of these pesticides in agriculture.

Development and Validation of a Prediction Model for Chronic Post-Surgical Pain After Thoracic Surgery in Elderly Patients: A Retrospective Cohort Study.

Purpose: Chronic post-surgical pain (CPSP) is one of the adverse outcomes after surgery, especially in thoracotomy. However, the prevalence of CPSP in elderly adults (≥65 years), is still limited. Therefore, the present study was undertaken to establish and validate the prediction model of CPSP in those patients after thoracic surgery, including thoracotomy and video-assisted thoracoscopic surgery. Patients and Methods: This retrospective, observational single-center cohort study was conducted in Nanfang Hospital, Southern Medical University, which randomly and consecutively collected 577 elderly patients who underwent thoracic surgery between January 1, 2017, and December 31, 2020. According to the Akaike information criterion, the prediction model was built based on all the data and was validated by calibration with 500 bootstrap samples. Results: The mean age of participants was 69.09±3.80 years old, and 63.1% were male. The prevalence of CPSP was 26.9%. Age more than 75 years, BMI, blood loss, longer length of hospital stays, and higher pre-operative neutrophil count were associated with CPSP. Except for these factors, we incorporated history of drinking to build up the prediction model. The areas under the curve (AUCs) of the prediction models were 0.66 (95% CI, 0.61-0.71) and 0.64 (95% CI, 0.59-0.69) in the observational and validation cohorts, respectively. And the calibration curve of the predictive model showed a good fit between the predicted risk of CPSP and observed outcomes in elderly patients. Conclusion: The present developed model may help clinicians to find high-risk elderly patients with CPSP after thoracic surgery and take corresponding measures in advance to reduce the incidence of CPSP and improve their life quality.

Tasks of COVID-19 prevention and control management teams at primary health care facilities in mainland China: a nationwide online cross-sectional survey.

BACKGROUND: This research aimed to investigate the tasks performed by Coronavirus Disease 2019(COVID-19) prevention and control management teams at primary healthcare (PHC) facilities during COVID-19 pandemic across the mainland China. METHODS: An online survey was performed and COVID-19 prevention and control management teams at PHC facilities were invited to participate in this research. The top 7 most important tasks in the three different periods of COVID-19 containment were selected and ranked. Participations of tasks were surveyed. RESULTS: A total of 998 valid responses (an effective rate of 99.11%) were collected. The respondents were divided into Group A (≤5 respondents within each PHC facility, n1 = 718) and Group B (> 5 respondents within each PHC facility, n2 = 280). The consensus was selected from top 7 most important tasks including screening at travel centers/intervals and screening at entry centers, at-home/centralized quarantine management, transferring, pre-examination/triage and fever sentinel surveillance clinic/fever clinic. Pre-examination/triage and fever sentinel surveillance clinic/fever clinic works became more significant in the regular prevention and control period. Adjusted analysis found that team members of Group A with a college, undergraduate college and graduate school educational background were less involved in pre-examination/triage works (aOR: 0.28; 95%CI: 0.09-0.86, P = 0.026; aOR: 0.30; 95%CI: 0.10-0.90, P = 0.031; aOR: 0.21; 95%CI: 0.05-0.82, P = 0.024). Those who were over the median age were twice more likely to be engaged in managing fever sentinel surveillance of clinic/fever clinic visitors (aOR: 2.18; 95%CI: 1.16-4.08, P = 0.015). Those being specialized in nursing and other specialties were less likely to participate in fever sentinel surveillance of clinic/fever clinic works (aOR: 0.44; 95%CI: 0.24-0.81, P = 0.009; aOR: 0.30; 95%CI: 0.16-0.58, P < 0.001). Those came from central and western China were less likely to participate in centralized quarantine management (aOR: 0.61; 95%CI: 0.38-0.98, P = 0.042; aOR: 0.64; 95%CI: 0.42-0.97, P = 0.037). Team members came from central and western China were twice less likely to participate in screening at travel centers/intervals (aOR: 1.75; 95%CI: 1.14-2.70, P = 0.011; aOR: 1.63; 95%CI: 1.07-2.48, P = 0.024). CONCLUSION: In mainland China, team members of COVID-19 prevention and control at PHC facilities are mainly responsible for screening, quarantine, transferring and monitoring during the COVID-19 pandemic. Pre-examination/triage and the fever sentinel surveillance clinic/fever clinic were gradually valued. Team members with lower educational background are competent in pre-examination/triage works, but more experienced general practitioners are more likely to be in charge of fever sentinel surveillance clinic/fever clinics work. The necessity of COVID-19 prevention and control management teams to participate in screening at travel centers/intervals is subjected to further discussions.

Vaccination coverage among COVID-19 prevention and control management teams at primary healthcare facilities in China and their attitudes towards COVID-19 vaccine: a cross-sectional online survey.

OBJECTIVE: To investigate the COVID-19 vaccination coverage rate and differences among various COVID-19 prevention primary healthcare (PHC) facilities in China and understand their attitudes towards COVID-19 vaccine. These findings are helpful to provide important suggestions to further improve national COVID-19 vaccination rate. DESIGN: A nationwide cross-sectional online survey was designed and conducted among COVID-19 prevention and control management teams at PHC facilities in mainland China. In the self-designed questionnaires, each subject was asked to evaluate on a 1-10 scale (10=extremely important/acceptable/influential) the COVID-19 vaccination importance, acceptance and factors related to vaccine hesitancy. SETTING: Subjects from 31 provinces and autonomous regions including minorities across mainland China were invited to complete the questionnaire between 22 February 2021 and 2 March 2021. PARTICIPANTS: Were selected by multistage stratified sampling, 998 valid questionnaires (valid rate 99.11%) were collected. The respondents were divided into group A (≤5 respondents within each PHC facility, n1=718) and group B (>5 respondents within each PHC facility, n2=280). OUTCOME MEASURES: Survey on vaccination rate and attitude towards COVID-19 vaccine included the following: (1) if the subjects think the vaccination is important in containment of COVID-19 pandemic (1-10 scale, 10=extremely important), (2) if they would accept COVID-19 vaccine (1-10 scale, 10=extremely acceptable) and (3) their opinions on 7 factors possibly related to vaccine hesitancy (1-10 scale, 10=extremely influential). All the items were designed based on the previous expert interviews. RESULTS: Our results showed vaccination rate was greater in group A (85.93%) than in group B (66.43%) (p<0.001). Detailed analyses revealed that in group A, male members were twice as likely to get vaccinated as compared with female members (adjusted OR (aOR): 2.07; 95% CI: 1.26 to 3.43, p=0.004). In group B, those who were at or under the median age had twice the odds of vaccination coverage compared with those who were over the median age (aOR: 2.29; 95% CI: 1.22 to 4.33, p=0.010). In addition, those who were specialised in traditional Chinese medicine were less likely to get vaccinated against COVID-19 compared with those who were specialised in general medicine, with the aOR: 0.10 (95% CI: 0.01 to 0.83, p=0.033). By analysing the factors that influenced the vaccination attitudes among the 998 respondents, we found no significant difference between the vaccinated and unvaccinated participants. However, further detailed analyses found that team members with undergraduate college education were less likely to score higher in COVID-19 vaccination importance than those with technical secondary school education (aOR: 0.35; 95% CI: 0.13 to 0.93, p=0.035); Furthermore, those with non-medical job titles had nearly twice the odds of giving a higher score for the uncertainty of vaccine efficacy compared with those with junior medical titles (aOR: 1.70; 95% CI: 1.02 to 2.85, p=0.016). Team members with a non-medical title were more likely to give a higher score for advice on social sources compared with those with a junior medical title (aOR: 1.70; 95% CI: 1.02 to 2.85, p=0.042). CONCLUSION: In PHC facilities, although there was a higher COVID-19 vaccination rate among COVID-19 prevention and control teams, some subgroups with different descriptive characters showed negative attitudes towards COVID-19 vaccination. Because primary care workers in China are highly expected to receive the vaccination, and support and educate the public for COVID-19 vaccination. Thus, it is important and necessary to continue to educate them about their vaccination concerns and change their attitudes towards vaccination. Our findings are highly beneficial for designing public vaccination education strategies.

Prevention and control of COVID-19 by primary health care facilities in China: a field-survey-based qualitative study in three typical cities.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) containment, primary health care (PHC) facilities inChina played an important role in providing both healthcare and public care services to community populations. The tasks of COVID-19 containment facilitated by PHC facilities were different among different regions and during different periods of COVID-19 pandemic. We sought to investigate the gaps on task participation, explore existing problems and provide corresponding solutions. METHODS: Semi-structured face-to-face interviews with COVID-19 prevention and control management teams of PHC facilities were conducted. Purposive stratified sampling was used and 32 team members of 22 PHC facilities were selected from Wuhan (as high-risk city), Shanghai (as medium-risk city) and Zunyi (as low-risk city). Framework analysis was employed to analyze the transcribed recordings. RESULTS: The main tasks of PHC facilities during the early period of the pandemic included assisting in contact tracing and epidemiological investigation, screening of populations at high-risk at travel centers/internals, house-by-house, or pre-examination/triage within PHC facilities; at-home/ centralized quarantine management; the work of fever sentinel clinics. Further analyses revealed the existing problems and suggestions for improvement or resolutions. Regular medical supply reserves were recommended because of the medical supply shortage during the pre-outbreak period. Temporarily converted quarantine wards and centralized quarantine centers could be used to deal with pressures on patients' treatment and management of the febrile patients. Only after strict evaluation of nucleic acid testing (NAT) results and housing conditions, decision on quarantine at-home or centralized quarantine centers could be made. Settings of fever sentinel clinics at PHC facilities allowed fever patients with no COVID-19 infection risks for treatment without being transferred to fever clinics of the designed secondary hospitals. Psychological intervention was sometimes in need and really helped in addressing individuals' mental pressures. CONCLUSIONS: During the COVID-19 containment, PHC facilities in China were responsible for different tasks and several problems were encountered in the working process. Accordingly, specific and feasible suggestions were put forward for different problems. Our findings are highly beneficial for healthcare teams and governments in handling similar situations.

Effects of Occupational Exposure to Waste Anesthetic Gas on Oxidative Stress and DNA Damage.

OBJECTIVE: The aim of the study was to investigate the potential effects of waste anesthetic gas (WAG) on oxidative stress, DNA damage, and vital organs. METHODS: A total of 150 members of the staff at a hospital were assigned to an exposure group or control group. The 68 operating room (OR) staff in the exposure group were exposed to WAG, and the 82 non-OR staff in the control group were not exposed to WAG. Air samples were collected in the OR, and the sevoflurane concentrations in the samples were determined. Superoxide dismutase (SOD), glutathione peroxidase (GSH-px), and malondialdehyde (MDA) in plasma from the participants were determined to assess oxidative stress. Western blot analysis was used to detect γH2AX in peripheral blood to assess DNA damage. Hematopoietic parameters, liver function, kidney function, and changes in electrophysiology were assessed to identify the effects on the vital organs. RESULTS: The mean (±standard deviation) sevoflurane concentration in 172 air samples from 22 operating rooms was 1.11 ± 0.65 ppm. The superoxide dismutase activity and vital organ parameters (lymphocyte, hemoglobin, and total protein concentrations and heart rate) were significantly lower (P < 0.05) in the exposed group than the control group. The malondialdehyde, total bilirubin, and creatinine concentrations and QT and QTc intervals were significantly higher (P < 0.05) in the exposed group than the control group. There were no significant differences between the glutathione peroxidase activities and γH2AX concentrations for the exposed and control groups. CONCLUSIONS: Long-term occupational exposure to waste anesthetic gas may affect the antioxidant defense system and probably affects vital organ functions to some extent. No correlation between DNA damage and chronic exposure to WAG was observed.

Genome-Wide Analysis Reveals the Role of Mediator Complex in the Soybean-Phytophthora sojae Interaction.

The mediator complex is an essential link between transcription factors and RNA polymerase II, and mainly functions in the transduction of diverse signals to genes involved in different pathways. Limited information is available on the role of soybean mediator subunits in growth and development, and their participation in defense response regulation. Here, we performed genome-wide identification of the 95 soybean mediator subunits, which were unevenly localized on the 20 chromosomes and only segmental duplication events were detected. We focused on GmMED16-1, which is highly expressed in the roots, for further functional analysis. Transcription of GmMED16-1 was induced in response to Phytophthora sojae infection. Agrobacterium rhizogenes mediated soybean hairy root transformation was performed for the silencing of the GmMED16-1 gene. Silencing of GmMED16-1 led to an enhanced susceptibility phenotype and increased accumulation of P. sojae biomass in hairy roots of transformants. The transcript levels of NPR1, PR1a, and PR5 in the salicylic acid defense pathway in roots of GmMED16-1-silenced transformants were lower than those of empty-vector transformants. The results provide evidence that GmMED16-1 may participate in the soybean-P. sojae interaction via a salicylic acid-dependent process.

[RhoA/Rho-kinase contributes to chronic pain following thoracotomy by up-regulating glutaminase 1 expression in rat spinal dorsal cord].

OBJECTIVE: To investigate whether RhoA/Rho-kinase contributes to the occurrence of chronic post-thoracotomy pain (CPSP) by up regulation of glutaminase 1 (GLS1) expression in the spinal dorsal cord. METHODS: Twenty five male Sprague Dawley (SD) rats were divided into control group (n=5) and model group (n=20). The rats in the model group were randomized into two sub groups (n=10) for observation on day 10 and day 21 after thoracotomy, and each group was further divided into CPSP and non CPSP groups according to the behavioral test results. All the rats were sacrificed after behavioral test for examination of GLS1 and RhoA expressions in the spinal cord using Western blotting and RT PCR. We also compared the effect of the Rho kinase inhibitor fasudil and saline, both injected intraperitoneally daily at 10 mg/kg for 7 consecutive days following thoracotomy, on CPSP and GLS1 expression in 30 male SD rats on day 21 after thoracotomy. RESULTS: Compared with the control group, the rats with CPSP showed significantly increased expressions of GLS1 and RhoA mRNA in the spinal cord on both day 10 and day 21 following thoracotomy (P<0.01), but the rats without CPSP did not show obvious changes in GLS1 and RhoA expressions. In fasudil treated rats, the mechanical pain threshold was obviously increased and the expressions of GLS1 and RhoA were significantly reduced as compared with those in saline treated rats (P<0.01). CONCLUSION: RhoA plays an important role in the occurence of CPSP by up-regulating the expression of GLS1 in the spinal dorsal cord of rats.

Perioperative Predictors of Extubation Failure and the Effect on Clinical Outcome After Infratentorial Craniotomy.

BACKGROUND The purpose of the study was to analyze the risk factors for failed extubation in subjects submitted to infratentorial craniotomy. MATERIAL AND METHODS Patients aged over 18 years who received infratentorial craniotomy for brain tumor resection were consecutively included in this study. Perioperative variables were collected and analyzed. Univariate analyses and multiple logistic regression were used to derive factors related to failed extubation. Patients had follow-up care until either out of hospital or death. RESULTS Throughout the course of the study, 2118 patients were eligible and 94 (4.4%) suffered from extubation failure at some point during their hospital stay. Five factors were recognized as independent risk factors for postoperative failed extubation: craniotomy history, preoperative lower cranial nerve dysfunction, tumor size, tumor position, and maximum change in blood pressure (BP) during the operation. Failed extubation was related to a higher incidence rate of pneumonia, mortality, unfavorable Glasgow Outcome Scale score, longer stay in the neuro-intensive care unit (ICU) and hospitalization, and higher hospitalization costs compared with successful extubation. CONCLUSIONS History of craniotomy, preoperative lower cranial nerve dysfunction, tumor size, tumor position, and maximum change in BP during the operation were independent risk factors related to postoperative failed extubation in patients submitted to infratentorial craniotomy. Extubation failure raises the incidences of postoperative pneumonia, mortality, and higher hospitalization costs, and prolongs neuro-ICU and postoperative length of stay.

[Effects of dexmedetomidine on propofol dosage in target-controlled infusion and hemodynamics during laparoscopic surgery under general anesthesia].

OBJECTIVE: To assess the effects of dexmedetomidine (Dex) on propofol dosage in target-controlled infusion (TCI) and hemodynamics in patients undergoing laparoscopic surgery under general anesthesia. METHODS: Sixty patients undergoing laparoscopic surgery under general anesthesia were randomly divided into control group (n=30) and the Dex group (n=30). The patients in Dex group received a loading dose of Dex (1 µg/kg, infused within 10 min) before the surgery followed by continuous infusion at the rate of 0.3 µg·kg(-1)·h(-1) till the end of the surgery, and the control patients received saline infusion in the same manner. Heart rate, blood pressure, bispectral index (BIS), and propofol dose in TCI were recorded during induction and maintenance of anesthesia. The incidence of hypotension and bradycardia were observed during and after the surgery. RESULTS: No difference was found in the incidence of hypotension and bradycardia between the control group and Dex group (P>0.05), but heart rate and blood pressure were lower in Dex group during extubation (P<0.05). The dose of propofol in TCI was significantly less in Dex group than in the control group (P<0.05). CONCLUSION: Dex can reduce hemodynamic abnormalities caused by extubation and decrease the dosage of propofol in TCI, and may serve as an ideal adjuvant drug for general anesthesia.

The metabolism of trifluoperazine (TFP) exhibits atypical kinetic behavior in both human liver microsomes (HLMs) and monkey liver microsomes (MyLM).

Glucuronidation reaction of trifluoperazine (TFP) is a typical probe reaction to phenotype the activity of UDP-glucuronosyltransferase 1A4. The present study aims to compare the metabolic behavior of TFP in the liver microsomes from human and cynomolgus monkey, including the kinetic type and parameters. In vitro human liver microsome incubation system was used. The Eadie-Hofstee plot was used to determine the kinetic type. The results showed that the data for human liver microsomes (HLMs) and monkey liver microsomes (MyLMs)-catalyzed glucuronidation were best fit to the substrate inhibition model. For the metabolism of TFP in HLMs, the kinetic parameters were calculated to be 40 ± 5 and 140 ± 20 µM for K m and K si values, respectively. For the MyLM-mediated metabolism of TFP, the K m and K si values were calculated to be 108 ± 10 and 250 ± 30 µM, respectively. The same metabolic kinetic type and different kinetic parameters were demonstrated for the metabolism of TFP between HLMs and MyLMs. All these data were helpful for understanding the metabolism difference of TFP between human and monkey.

Analysis of genetic variability and relationships among Mentha L. using the limonene synthase gene, LS.

The genus Mentha comprises a group of aromatic plants with worldwide distribution. Because of frequent interspecific hybridization, the genetic relationships within the genus are not clearly understood. Limonene synthase, which catalyses the first committed step in the essential oil monoterpene biosynthetic pathway, is considered to be a possible rate limiting enzyme. With the homology-based cloning method, primers were designed according to cDNA sequence to amplify full-length DNA sequences in 13 Mentha samples from five species, using Perilla as an outgroup. Analyses of gene structure, length variation, GC-content, Ts/Tv ratio and evolutionary diversity were carried out. Consensus phylogenetic trees were obtained using maximum likelihood, neighbor-joining, and maximum parsimony, respectively, based on the full-length genomic DNA sequences, complete ORF coding sequences and predicted amino acid sequences. The results presented here based on the sequence of MhLS provide the first credibly supported genetic relationships for Mentha, which enables a basis for further mint taxonomy, cultivation and breeding.

[Expressions of neuropathic pain-related proteins in the spinal cord dorsal horn in rats with bilateral chronic constriction injury].

OBJECTIVE: To evaluate the pain-related behavioral changes in rats with bilateral chronic constriction injury(bCCI)and identify the expressions of neuropathic pain-related proteins. METHODS: The bCCI models were established by ligating the sciatic nerves in female Sprague Dawley rats. Both mechanical hyperalgesia and cold hyperalgesia were evaluated through electronic von Frey and acetone method. Liquid chromatography-mass spectrometry/mass spectrometry was applied to characterize the differentially expressed proteins. RESULTS: Both mechanical withdrawal threshold and cold hyperalgesia threshold decreased significantly on the postoperative day 7 and 14, when compared with na ve or sham rats(P <0.05). Twenty five differentially expressed proteins associated with bilateral CCI were discovered, with eighteen of them were upregulated and seven of them downregulated. CONCLUSIONS: The bCCT rats have remarkably decreased mechanical and cold hyperalgesia thresholds. Twenty five neuropathic pain-related proteins are found in the spinal cord dorsal horn.

Prevalence and risk factors of chronic post-thoracotomy pain in Chinese patients from Peking Union Medical College Hospital.

BACKGROUND: In clinical practice, the mechanisms underlying chronic post-surgical pain (CPSP) remain insufficiently understood. The primary goals of this study were to determine the incidence of chronic pain after thoracic surgery and to identify possible risk factors associated with the development of chronic post-thoracotomy pain in Chinese patients. The secondary goal was to determine whether the difference between pre- and post-operative white blood cell (WBC) counts could predict the prevalence of CPSP after thoracotomy. The impact of chronic pain on daily life was also investigated. METHODS: We contacted by phone 607 patients who had undergone thoracotomy at our hospital during the period February 2009 to May 2010. Statistical comparisons were made between patients with or without CPSP. RESULTS: were ultimately analyzed from 466 qualified patients. The overall incidence of CPSP was 64.5%. Difference between pre- and post-operative WBC counts differed significantly between patients with or without CPSP (P < 0.001) and was considered as an independent risk factor for the development of CPSP following thoracotomy (P < 0.001). Other predictive factors for chronic pain included younger age (< 60 years, P < 0.001), diabetes mellitus (P = 0.023), acute post-operative pain (P = 0.005) and the duration of chest tube drainage (P < 0.001). At the time of interviews, the pain resulted in at least moderate restriction of daily activities in 15% of the patients, of which only 16 patients had paid a visit to the doctor and only three of them were satisfied with the therapeutic effects. CONCLUSIONS: Chronic pain is common after thoracotomy. WBC count may be a new independent risk factoring surgical patients during peri-operative period. Besides, age, diabetes mellitus, acute post-operative pain, and duration of chest tube drainage may also play a role in chronic post-surgical pain occurrence.

Co-expression of KCNE2 and KChIP2c modulates the electrophysiological properties of Kv4.2 current in COS-7 cells.

AIM: Several beta-subunits have been suggested to modulate the electrophysiological properties of the transient outward current (I(to)) in cardiac myocytes, including the obligatory beta-subunit K+-channel interacting protein (KChIP2) and KCNE2. However, neither KChIP2 nor KCNE2 modulation of Kv4.x (x=2 and/or 3) can fully recapitulate the electrophysiological properties of native I(to). The present study is to investigate how I(to) current is modulated when both KChIP2 and KCNE2 are coexpressed. METHODS: Kv4.2, KChIP2c, and KCNE2 cDNA were simultaneously transfected into COS-7 cells at a molar ratio of 3:1:1. Whole-cell currents were recorded by the patch-clamp method. RESULTS: In comparison with the current regulated by KChIP2c alone, the co-expression of KCNE2 further slowed Kv4.2 current inactivation kinetics, but diminished KChIP2c-induced positive shift of the voltage-dependent activation of Kv4.2 current. Importantly, co-expression of KCNE2 accelerated the current recovery from inactivation, and caused an povershootq of peak current amplitude during Kv4.2 current recovery, a phenomenon which has been uniquely described for human I(to). However, co-expression of KCNE2 exerted no further effect on Kv4.2 current amplitude, the rate of Kv4.2 current activation and voltage-dependent inactivation. CONCLUSION: Co-expression of Kv4.2 with KChIP2c and KCNE2, but not with KChIP2c or KCNE2 alone, yields a current profile similar to native I(to). Both KChIP2c and KCNE2 simultaneously participate in recapitulation of the electrophysiological properties of I(to) in cardiac myocytes.

Protective effects of alanyl-glutamine on acute lung injury induced by lipopolysaccharide in rats.

OBJECTIVE: To investigate the effect of alanyl-glutamine (Ala-Gln) on acute lung injury (ALI) in rats induced by sepsis and its mechanisms. METHODS: Forty healthy adult Wistar rats were randomly divided into a control group, a lipopolysaccharide (LPS)-induced shock group, an Ala-Gln treated group, and a glutamine (Gln) treated group. The control group received an intravenous infusion of 28 mL/kg lactated Ringeros solution(LR). The LPS-induced shock group received an intravenous administration of 25 mL/kg LR, and then 3 mL/kg (6 mg/kg) LPS (L-2880, Sigma, America). The Ala-Gln treated group received 4.5% Dipeptiven (25 mL/kg, equaling 0.75 g/kg Gln) immediately before 3 mL/kg (6 mg/kg) LPS.The Gln treated group received 3% glutamine ( 25 mL/kg, 0.75 g/kg) immediately before 3 mL/kg (6 mg/kg) LPS. Serum (1 mL) was drawn via the femoral vein or cardiac puncture before LPS injection (T(0)) and 6 h after the administration of LPS (T(1)), respectively. All rats were killed 6 h after LPS infusion. The samples of pulmonary tissue and lung lavage fluid were collected after experiments. Tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-8 (IL-8) in the serum at T(0) and T(1) were detected by ELISA. Apoptosis in the lung epithelial cells was detected with TUNEL assays. The lung wet/dry(W/D)weight ratio and total protein in the bronchoalveolar lavage fluid (BALF) were measured. RESULTS: Six hours after the infusion of LPS (T(1)), the plasma concentrations of TNF-alpha, IL-1beta, and IL-8 were much lower in the Ala-Gln treated group and the Gln treated group than those in the LPS-induced shock group (P<0.05). Compared with the LPS-induced shock group, Ala-Gln and Gln significantly reduced the increase in the lung wet/dry weight ratio (P<0.05) and attenuated the morphological lung damage. CONCLUSION: Intravenous administration of Ala-Gln can effectively protect the lung from sepsis induced injury.