[Determination of nine organic amine compounds in CO2 absorption liquid by hydrophilic interaction liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry].

Carbon dioxide (CO2) absorption and capture is an effective measure to achieve the "dual carbon" goal of carbon peak and carbon neutrality in China. Organic amine compounds are widely used in the industrial separation and recovery of CO2. Thus, the establishment of analytical methods for organic amine compounds is of great significance for the research and development of carbon capture and storage (CCS) technology and carbon capture, utilization and storage (CCUS) technology. In this study, a method was developed for the determination of nine organic amine compounds in CO2 absorption liquid by hydrophilic interaction liquid chromatography (HILIC)-electrostatic field orbitrap high resolution mass spectrometry. The sample was diluted with water and filtered through a 0.22 µm nylon membrane before sampling and analysis. An Accucore HILIC column (100 mm×2.1 mm, 2.6 µm) was used for separation at 30 ℃. Gradient elution was conducted using 90% acetonitrile aqueous solution containing 5 mmol/L ammonium formate and 0.1% formic acid as mobile phase A and 10% acetonitrile aqueous solution containing 5 mmol/L ammonium formate and 0.1% formic acid as mobile phase B. Determination was performed using an electrospray ion source (ESI) in the positive ion mode. The quantitative analysis was carried out by standard addition method. The chromatographic retention performance of different chromatographic columns and the influence of different mobile phases on the separation of the organic amine compounds were compared, and the method was validated. The results showed that the linear ranges of the nine organic amine compounds were 0.04-25000 ng/mL with the linear correlation coefficients (R2) greater than 0.9910. The limits of detection (LODs) of the method were in the range of 0.0004-0.0080 ng/mL, and the limits of quantification (LOQs) of the method were in the range of 0.0035-0.0400 ng/mL. The average recoveries of the method ranged from 85.30% to 104.26% with relative standard deviations (RSDs) of 0.04%-7.95% at the spiked levels of 1, 1.5 and 3 times sample concentration. The established method was applied to detect the absorption waste liquid of a cement plant, and nine organic amine compounds could be effectively detected. The stability of the actual sample was tested, and the RSDs were 0.10%-6.35% in 48 h at 4 ℃. The method is sensitive, rapid and accurate for the determination of the nine organic amine compounds in industrial waste water. It can provide reference for the detection of organic amine compounds, and provide strong technical support for the research and industrial application of CO2 capture technology.

0D hybrid indium halides with highly efficient intrinsic broadband light emissions.

Two new zero-dimensional (0D) hybrid indium halides of [H2DMP]2InX7·2H2O (X = Cl, Br) were designed based on [InX6]3- octahedra as optically active centers. Remarkably, these 0D halides display intrinsic broadband yellow-orange light emissions with highest quantum yield of 58.53% exceeding all previously reported 0D indium halides.

Zero-Dimensional Hybrid Indium Halides with Efficient and Tunable White-Light Emissions.

Two-dimensional hybrid lead perovskites have attracted a great deal of attention in white-light-emitting diodes, but the serious toxicity of Pb2+ and the limited photoluminescence quantum yield (PLQY) still restrict further optoelectronic application. To address these issues, a new combining photon strategy was proposed to achieve highly efficient broadband white-light emission in a new family of zero-dimensional (0D) indium halides based on an [InCl6]3- octahedron. Remarkably, these 0D halides display dual-band white-light emission derived from the synergistic work of blue- and yellow-light-emitting bands, which can be ascribed to the radiative recombination of bound excitons in organic cations and self-trapped excitons in inorganic anions, respectively, based on spectroscopy and theoretical studies. In-depth first-principles calculation demonstrates that the increased structural deformability effectively improves the PLQY from 7.01% to 18.56%. As a proof of concept, this work provides a profound understanding for advancing the rational design of novel single-component 0D lead-free halides as high-performance white-light emitters.

Zero-dimensional Hybrid Antimony Halide with Intrinsic Cyan Light Emission.

Recently, zero-dimensional (0D) hybrid metal halides have attracted intensive attention with wide applications in solid-state lighting and display diodes. Herein, by using a facile wet-chemistry method, we prepared one new 0D hybrid antimony halide of [HMHQ]2 SbCl5 ⋅ 2H2 O (MHQ=2-methyl-8-hydroxyquinoline) based on the discrete [SbCl5 ]2- unit. Remarkably, the bulk crystals of [HMHQ]2 SbCl5 ⋅ 2H2 O exhibit strong cyan light emission with a promising photoluminescence quantum yield (PLQY) of 18.92%. Systematical studies disclose that the cyan emission is mainly derived from the radiative recombination within conjugated organic cation. Benefiting from the promising luminescent performance, this 0D antimony halide can be utilized as an excellent down-conversion light emitting luminescent material to assemble white light-emitting diodes with high color rendering index (CRI) of 90.2.

[In-Vivo Noninvasive Measurement of Human Blood Glucose Levels by Mid-Infrared Spectrograph with External CO(2) Laser Source].

Diabetes is a kind of diseases which does harm to people's health, and the detection of human blood glucose levels utilizing blood samples will result in pain even infection for patients. Thus the in-vivo noninvasive measurement of human blood glucose levels has vital value in clinical diagnosis, detection and therapy, and it also is a very hot research topic with challenging. At present, as to various noninvasive detection methods, the technology based on mid-infrared absorption spectrophotometry with ATR has been gaining increasing attention. However, when carrying out noninvasive measurement of human blood glucose levels by means of the spectrophotometry equipped with routine light sources, the penetration depth of probe light in human tissues is low and thus it is very difficult to reach the stromal layer containing body fluids and especially dermis layer containing blood for probe light, which resulting in low relativity between experimental data and real human blood glucose levels and thus limiting the clinical application. Generally, not only the mid-infrared laser with high strength and high purity can deeper penetrate the human tissues, but also the output wavelengths at 1 035 cm(-1) of CO2 laser very coincide with the fundamental frequency characteristic absorption at 1 029 cm(-1) of glucose. Thus, in this work, a novel noninvasive mid-infrared measurement system to detect human blood glucose levels has been successfully assembled, in which a CO2 laser was used a self-defined external light source of the new mid-infrared absorption spectrophotometry with ATR. In this system, the absorbance of human fingertip at 1 035 cm(-1) has been measured when external CO2 laser source was used as probe light, at the same time, the mid-infrared absorption spectra of fingertip have been also obtained and absorbance at 1 492 cm(-1) has been recorded. The human blood glucose levels were determined synchronously by means of the routine medical method. The experimental results showed that the ratio in fingertip between absorbance at 1 035 cm(-1) from the laser source and one at 1 492 cm(-1) from mid-infrared absorption spectrophotometry could synchronously change with the human blood glucose levels, and the ratio presents certain positive relativity with the real human blood glucose levels(R=0. 812 5). Thus the measurement data could be used as a new index of blood glucose level in human body, which showed the potential in clinical diagnosis of the ATR mid-infrared absorption spectrophotometry with external CO(2) laser source in noninvasive measurement of human blood glucose levels.

An Engineered Endomorphin-2 Gene for Morphine Withdrawal Syndrome.

An optimal therapeutics to manage opioid withdrawal syndrome is desired for opioid addiction treatment. Down-regulation of endogenous endomorphin-2 (EM2) level in the central nervous system after continuous morphine exposure was observed, which suggested that increase of EM2 could be an alternative novel method for opioid dependence. As a short peptide, the short half-life of EM2 limits its clinical usage through conventional administration. In the present study, we engineered an EM2 gene using a signal peptide of mouse growth factor for an out-secretory expression of EM2 and an adenovirus as a vector, which ultimately sustained the release of EM-2. After administration of the adenovirus in central nervous system, a sustained increase of EM2 level in the cerebral spinal fluid (CSF) was observed along with a reduction of morphine withdrawal syndrome. These findings suggest that the engineered EM2 gene delivered to the central nervous system could be a novel therapeutics for withdrawal syndrome in opioid dependent subjects.

Particularly interesting Cys-His-rich protein is highly expressed in human intracranial aneurysms and resists aneurysmal rupture.

Particularly interesting Cys-His-rich protein (PINCH) has several biological functions in cancer development, invasion and metastasis in malignant cells, and the expression of PINCH is upregulated in several cancer types, including breast cancer, gastric adenocarcinoma and rectal cancer. However, the contribution of PINCH to human cerebral aneurysms remains largely unknown. Therefore, the significance of PINCH expression in cerebral aneurysm growth and rupture was examined in the present study. The protein expression levels of alpha-smooth muscle actin, osteopontin (OPN), matrix metalloproteinase (MMP) 9 and PINCH were evaluated using immunohistochemistry and western blot analyses. The results demonstrate that the protein expression levels of OPN, MMP9 and PINCH in the unruptured intracranial aneurysm (UA) and ruptured intracranial aneurysm (RA) groups were markedly higher than those of the control group, whereas OPN and PINCH expression levels were decreased in the RA group compared to those of the UA group. In addition, there was a strong correlation between PINCH and tumor size (r=0.650 and P=0.0026), as well as between PINCH and OPN (r=0.639 and P=0.0033) in the unruptured cerebral aneurysms. However, the correlation between PINCH and tumor size (r=0.450 and P=0.1393) and between PINCH and OPN (r=0.366 and P=0.2426) revealed no obvious difference in the ruptured cerebral aneurysms. In conclusion, PINCH was highly expressed in the UAs, which may be a critical factor for preventing aneurysmal rupture. Moreover, PINCH may facilitate intracranial aneurysm progression, at least partially, through the activation of extracellular signal-regulated kinase signaling and the suppression of c-Jun N-terminal kinase signaling.

Metabolism and pharmacokinetics of 8-hydroxypiperidinylmethyl-baicalein (BA-j) as a novel selective CDK1 inhibitor in monkey.

Cyclin-dependent kinase 1 (CDK1) is the only necessary CDK in the cell proliferation process and a new target in the research and development of anti-cancer drugs. 8-Hydroxypiperidinemethyl-baicalein (BA-j) is a Mannich base derivative of baicalein (BA) isolated from Scutellaria baicalensis, as a novel selective CDK1 inhibitor. 12 metabolites of BA-j in the monkey urine were identified by LC-MS-MS and (1)H NMR. The major metabolic pathways of BA-j, by capturing oxygen free radicals ((.)O2(-)) and releasing peroxides (H2O2), are degraded into active intermediate metabolite dihydroflavonol, then into main metabolite M179 by Shiff reaction, second metabolite M264 by sulfation, trace amount of metabolite M559 by glucuronidation UGT1A9, and without metabolism by CYP3A4. The metabolic process of BA-j by regulating intracellular reactive oxygen species (ROS) was related with BA-j selectively inducing apoptosis in cancer cells. Pharmacokinetics of 10mg/kg oral BA-j in monkey by HPLC-UV was best fitted to a two-compartment open model, with t1/2(ß) of 4.2h, Cmax 25.4µM at 2h, and Vd 12.6L, meaning the drug distributing widely in body fluids with no special selectivity to certain tissues, and being able to permeate through the blood-brain barrier. The protein binding rate of BA-j was 91.8%. BA-j has excellent druggability for oral administration or injection, and it may be developed into a novel anti-cancer drug as a selective CDK1 inhibitor.

[Influence of cationic cyclopeptide on microstructure and permeability of Caco-2 cell membrane].

The microstructure of cationic cyclopeptide (TD-34) treated Caco-2 cell membrane was observed, and we discussed the relationship between membrane structure and insulin transmembrane permeability. Atomic force microscope (AFM) was used to observe living cell membrane in air condition and tapping mode. Results showed that the surface of Caco-2 cell membrane treated with TD-34 lost its smoothness and nearly doubled its roughness. Apparent permeability coefficients (P(app)) of insulin in Caco-2 cell monolayers increased 2.5 times. In conclusion, AFM can be used to observe microstructure of cationic cyclopeptide treated cell membrane and cationic cyclopeptide enhanced insulin delivery across Caco-2 cell membrane by increasing membrane fluidity.

Glutamine supplementation for critically ill adults.

BACKGROUND: Glutamine is a non-essential amino acid which is abundant in the healthy human body. There are studies reporting that plasma glutamine levels are reduced in patients with critical illness or following major surgery, suggesting that glutamine may be a conditionally essential amino acid in situations of extreme stress. In the past decade, several clinical trials examining the effects of glutamine supplementation in patients with critical illness or receiving surgery have been done, and the systematic review of this clinical evidence has suggested that glutamine supplementation may reduce infection and mortality rates in patients with critical illness. However, two recent large-scale randomized clinical trials did not find any beneficial effects of glutamine supplementation in patients with critical illness. OBJECTIVES: The objective of this review was to:1. assess the effects of glutamine supplementation in critically ill adults and in adults after major surgery on infection rate, mortality and other clinically relevant outcomes;2. investigate potential heterogeneity across different patient groups and different routes for providing nutrition. SEARCH METHODS: We searched the Cochrane Anaesthesia Review Group (CARG) Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2013, Issue 5); MEDLINE (1950 to May 2013); EMBASE (1980 to May 2013) and Web of Science (1945 to May 2013). SELECTION CRITERIA: We included controlled clinical trials with random or quasi-random allocation that examined glutamine supplementation versus no supplementation or placebo in adults with a critical illness or undergoing elective major surgery. We excluded cross-over trials. DATA COLLECTION AND ANALYSIS: Two authors independently extracted the relevant information from each included study using a standardized data extraction form. For infectious complications and mortality and morbidity outcomes we used risk ratio (RR) as the summary measure with the 95% confidence interval (CI). We calculated, where appropriate, the number needed to treat to benefit (NNTB) and the number needed to treat to harm (NNTH). We presented continuous data as the difference between means (MD) with the 95% CI. MAIN RESULTS: Our search identified 1999 titles, of which 53 trials (57 articles) fulfilled our inclusion criteria. The 53 included studies enrolled a total of 4671 participants with critical illness or undergoing elective major surgery. We analysed seven domains of potential risk of bias. In 10 studies the risk of bias was evaluated as low in all of the domains. Thirty-three trials (2303 patients) provided data on nosocomial infectious complications; pooling of these data suggested that glutamine supplementation reduced the infectious complications rate in adults with critical illness or undergoing elective major surgery (RR 0.79, 95% CI 0.71 to 0.87, P ＜ 0.00001, I² = 8%, moderate quality evidence). Thirty-six studies reported short-term (hospital or less than one month) mortality. The combined rate of mortality from these studies was not statistically different between the groups receiving glutamine supplement and those receiving no supplement (RR 0.89, 95% CI 0.78 to 1.02, P = 0.10, I² = 22%, low quality evidence). Eleven studies reported long-term (more than six months) mortality; meta-analysis of these studies (2277 participants) yielded a RR of 1.00 (95% CI 0.89 to 1.12, P = 0.94, I² = 30%, moderate quality evidence). Subgroup analysis of infectious complications and mortality outcomes did not find any statistically significant differences between the predefined groups. Hospital length of stay was reported in 36 studies. We found that the length of hospital stay was shorter in the intervention group than in the control group (MD -3.46 days, 95% CI -4.61 to -2.32, P < 0.0001, I² = 63%, low quality evidence). Slightly prolonged intensive care unit (ICU) stay was found in the glutamine supplemented group from 22 studies (2285 participants) (MD 0.18 days, 95% CI 0.07 to 0.29, P = 0.002, I² = 11%, moderate quality evidence). Days on mechanical ventilation (14 studies, 1297 participants) was found to be slightly shorter in the intervention group than in the control group (MD - 0.69 days, 95% CI -1.37 to -0.02, P = 0.04, I² = 18%, moderate quality evidence). There was no clear evidence of a difference between the groups for side effects and quality of life, however results were imprecise for serious adverse events and few studies reported on quality of life. Sensitivity analysis including only low risk of bias studies found that glutamine supplementation had beneficial effects in reducing the length of hospital stay (MD -2.9 days, 95% CI -5.3 to -0.5, P = 0.02, I² = 58%, eight studies) while there was no statistically significant difference between the groups for all of the other outcomes. AUTHORS' CONCLUSIONS: This review found moderate evidence that glutamine supplementation reduced the infection rate and days on mechanical ventilation, and low quality evidence that glutamine supplementation reduced length of hospital stay in critically ill or surgical patients. It seems to have little or no effect on the risk of mortality and length of ICU stay, however. The effects on the risk of serious side effects were imprecise. The strength of evidence in this review was impaired by a high risk of overall bias, suspected publication bias, and moderate to substantial heterogeneity within the included studies.

Proteinase-activated receptor 1 contributed to up-regulation of enkephalin in keratinocytes of patients with obstructive jaundice.

BACKGROUND: Skin synthesis of endogenous opioids such as enkephalin is considered to be increased in cholestatic rodents, which may induce antinociception in cholestatic liver disease. No studies have reported yet the expression of skin enkephalin in patients with cholestasis. METHODS: Electrical pain threshold, postoperative morphine consumption, and skin enkephalin expression were measured in patients with jaundice (n = 18) and control patients (n = 16). Male Sprague-Dawley rats (n = 52) and human keratinocyte cell line HaCaT were used in vivo and in vitro studies, respectively. Nociceptive thresholds and plasma and skin levels of methionine-enkephalin were compared in protease-activated receptors-1-antagonized and control bile duct-ligated rats. In in vitro study, the effect on thrombin-induced enkephalin expression was examined and the role of extracellular regulated protein kinases 1/2 and p38 was investigated. RESULTS: The authors found that: (1) the electrical pain threshold (mean ± SD) was 1.1 ± 0.1 mA in control patients, whereas it was significantly increased in patients with jaundice (1.7 ± 0.3 mA); 48-h postoperative morphine consumption was approximately 50% higher in the control group than that in the group with jaundice; (2) Skin keratinocytes enkephalin expression was increased in the patients with jaundice; (3) Protease-activated receptors-1 antagonist 1 µg·kg(-1)·day(-1) treatment to the bile duct-ligated rats significantly reduced plasma levels of methionine-enkephalin, nociceptive thresholds, and keratinocytes enkephalin expression; and (4) protease-activated receptors-1 activation induced enkephalin expression through phosphorylation of extracellular regulated protein kinases 1/2 and p38 in keratinocytes. CONCLUSION: Protease-activated receptors-1 activation in peripheral keratinocytes may play an important role in the local synthesis of enkephalin during cholestasis.

Controlled low central venous pressure reduces blood loss and transfusion requirements in hepatectomy.

AIM: To evaluate the effect of low central venous pressure (LCVP) on blood loss and blood transfusion in patients undergoing hepatectomy. METHODS: Electronic databases and bibliography lists were searched for potential articles. A meta-analysis of all randomized controlled trials (RCTs) investigating LCVP in hepatectomy was performed. The following three outcomes were analyzed: blood loss, blood transfusion and duration of operation. RESULTS: Five RCTs including 283 patients were assessed. Meta-analysis showed that blood loss in the LCVP group was significantly less than that in the control group (MD = -391.95, 95%CI: -559.35--224.56, P < 0.00001). In addition, blood transfusion in the LCVP group was also significantly less than that in the control group (MD = -246.87, 95%CI: -427.06--66.69, P = 0.007). The duration of operation in the LCVP group was significantly shorter than that in the control group (MD = -18.89, 95%CI: -35.18--2.59, P = 0.02). Most studies found no significant difference in renal and liver function between the two groups. CONCLUSION: Controlled LCVP is a simple and effective technique to reduce blood loss and blood transfusion during liver resection, and appears to have no detrimental effects on liver and renal function.

A simple, fast correction method of triglyceride interference in blood hemoglobin automated measurement.

BACKGROUND: To establish a reliable correction method for automated hemoglobin (HGB) measurement by minimizing the interference from blood high triglyceride (TG). METHODS: Fifty whole blood samples and 50 plasma samples containing variable TG concentrations were used to determine the centrifugation speed and time. Complete blood cell counts (CBCs) were performed by an automated hematology analyzer for 102 blood samples, in which high-level TG were artificially added. The same blood samples were centrifuged at low -speed to separate the plasma from blood cells. Then the plasma was analyzed by the same analyzer. By using the two CBC results, a correction formula was established to calculate the corrected HGB, mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) values. Comparisons were also made of HGB, MCH, and MCHC values before and after correction of in-patient individuals who received intralipid and developed lipemia. RESULTS: The percentage differences between the corrected and true values of HGB, MCH and MCHC were -0.28%, 0.06%, and -0.31%, respectively. The correlation coefficients of corrected values versus true values of HGB, MCH, and MCHC were 0.989, 0.935, and 0.717, respectively. This correction method was also effective for native lipemic samples. CONCLUSION: High blood TG level can cause blood turbidity and erroneously high HGB results by hematology analyzers commonly used in clinical laboratories. Adding a simple step of low-speed centrifugation and measurement of HGB in the plasma fraction allows a quick correction of HGB measurement in lipemic blood samples.

Equal contributions and credit: an emerging trend in the characterization of authorship in major anaesthesia journals during a 10-yr period.

BACKGROUND: The practice of giving certain authors equal credit in original research publications was increasingly common in some specialty. This study aimed to investigate the prevalence and characteristics of designating some authors with equally credited authors (ECAs) in major anaesthesia journals. METHODOLOGY/PRINCIPAL FINDINGS: The practice of giving authors equal credit was searched and identified in the three major anaesthesia journals between January 1, 2002 and December 31, 2011. Papers with ECAs had a higher proportion of the total number of articles in 2011 versus published in 2002 (Anesthesiology, 8.8% vs. 0.9%; British Journal of Anaesthesia, 8.8% vs. 0%; Anesthesia & Analgesia, 3.4% vs. 0.3%; totally, 6.4% vs. 0.4%). A significant increasing trend in annual proportion of articles with ECA was found in the three journals. The first two authors listed in the byline had equal credit in most cases. CONCLUSIONS/SIGNIFICANCE: The practice of giving authors equal credit in original research papers is increasingly common in major anaesthesia journals. It may be warranted for the journals to guide the authors how to regard this practice.

Assessing the national productivity in subspecialty critical care medicine journals: a bibliometric analysis.

PURPOSE: In recent years, significant growth has been seen in the subspecialty critical care medicine. However, the national productivity to the subspecialty critical care medicine remains unknown. We therefore intended to reveal the national contribution in the subspecialty critical care medicine journals. MATERIALS AND METHODS: Articles published in 20 highly cited journals in subspecialty critical care medicine from 2006 to 2010 were retrieved from Web of Science and PubMed. The number of total articles and randomized, controlled trials, the per capita numbers, total impact factors (IFs), and citations were tabulated to assess the contribution of different countries. RESULTS: A total number of 17,667 articles were published in the 20 journals from 2006 to 2010 worldwide. North America, West Europe, and East Asia were the most productive regions. High-income countries published 89.68% of the total articles. The United States published the most number of articles in 2006 to 2010 (6659/17,667, or 37.69%), followed by United Kingdom, Germany, France, and Australia. Besides, the United States also had the most number of randomized, controlled trials (260), the highest total impact factors (27,206.55), and the highest total citations (84,170). When normalized to population size, Australia had the highest number of articles per million population, followed by Netherlands, Switzerland, Austria, and Belgium. CONCLUSION: The United States is the most productive country in the subspecialty critical care medicine. When normalized to population size, Australia and some European countries might be more productive.

Citation classics in main pain research journals.

The number of citations of an article in scientific journals reflects its impact on a specific biomedical field and its recognition in the scientific community. In the present study, we identified and analyzed the characteristics of the 100 most frequently cited articles published between 1970 and 2010 in journals pertaining to pain research and related fields. These articles were identified using the database of the Science Citation Index (1970 to present). The most cited article received 3,017 citations and the least cited article received 302 citations, with a mean of 585 citations per article. These citation classics were published in six high-impact journals, led by Pain (84 articles). Of the 100 articles, 39 were observational studies, 25 were review articles, and 20 concerned basic science. The articles originated from 14 countries, with the United States contributing 47 articles; 67 institutions produced these 100 top-cited articles, led by National Institutes of Health of the United States (8 articles) and University College London (6 articles); 18 persons authored 2 or more of the top-cited articles. This analysis of the top citation classics allows for the recognition of major advances in pain research and gives a historical perspective on the scientific progress of this specialty.

Suppression of acute morphine withdrawal syndrome by adenovirus-mediated ß-endorphin in rats.

BACKGROUND: Endogenous ß-endorphin (ß-EP) in the central nervous system (CNS) is decreased upon opioid addiction. The current study examined whether exogenous ß-EP, delivered using an adenoviral vector into the CNS could attenuate morphine withdrawal syndrome in rats. METHODS: The model of opioid-dependent rats was set up by receiving subcutaneous injection of morphine using an escalating regimen for 6days (5, 10, 20, 40, 50, 60mg/kg, three times/day). The adenovirus mediated ß-EP gene was constructed based on our previous work. The ilea of opioid-dependent rats were isolated and treated with the supernatant of Ad-NEP. The basic and naloxone-induced (4µm/l) contractions of dependent ilea were recorded. The Ad-NEP was injected into the left lateral ventricle of the addition rats. The expression of the ß-EP gene was verified by radioimmunoassay of the cerebrospinal fluid (CSF) and immunocytochemistry for ß-EP. Withdrawal syndrome was evaluated after intraperitoneal injection of naloxone. RESULTS: The contractions of dependent ilea were attenuated with supernatant containing ß-EP expressed by Ad-NEP. Injection of the Ad-NEP resulted in significant increases in ß-EP level in the CSF and ß-EP-positive neurons. Rats receiving adenovirus carrying the ß-EP gene had significantly less severe withdrawal symptoms upon naloxone challenge. CONCLUSIONS: Exogenous ß-EP mediated by adenovirus could attenuate withdrawal syndrome in morphine-dependent rats.

Pharmacokinetic study of lappaconitine hydrobromide in mice by LC-MS.

A high sensitive and rapid method was developed for the analysis of lappaconitine in mouse plasma using liquid chromatography coupled to mass spectrometry (LC-MS). Detection was performed by positive ion electrospray ionization (ESI) in multiple reaction monitoring (MRM) mode, monitoring the transitions m/z 585 --> m/z 535 and m/z 356 --> m/z 192, for the quantification of lappaconitine and tetrahydropalmatine (internal standard, IS), respectively. The method was linear over the concentration range of 3.0-2000.0 ng x mL(-1). The lower limit of quantification was 3.0 ng x mL(-1). Intra- and inter-run precisions (RSD) were both less than 9.9% and accuracy (RE) within +/- 4.8%. After single intravenous injections of lappaconitine hydrobromide at 1.0, 2.0 and 4.0 mg x kg(-1), the elimination half-lives (t(1/2)) were 0.47, 0.48 and 0.49 h, and the areas under the curve (AUC(0-t)) were 55.5, 110.5 and 402.9 ng x h x mL(-1), separately. The pharmacokinetic profile of lappaconitine was linear at relatively lower dose levels (1.0-2.0 mg x kg(-1)). When the dose increased farther to 4.0 mg x kg(-1), the Vz and CL decreased, and the increase fold of the AUC was much larger than that of the dose.