Improved quantitative determination of (R)- and (S)-rabeprazole sodium and its metabolites in rat plasma by LC-MS/MS and its application to a toxicokinetic study

There exist two enantiomers: (R)- and (S)-rabeprazole. (R)-rabeprazole offers specific pharmacokinetic advantages and enhanced therapeutic efficacy, warranting further investigation and development. Here, we developed a simple and rapid chiral liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to simultaneously quantify rabeprazole enantiomers and their metabolites (rabeprazole sulfoxide and desmethyl rabeprazole enantiomers) and a LC-MS to quantify rabeprazole thioether. As for the chiral LC-MS/MS method, Chiral-AGP column (150 × 4 mm, 5 μm) was used and its mobile phase was acetonitrile (mobile phase A) and 10 mmol/L ammonium acetate (mobile phase B) (linear gradient profile: 0 min, 10 % B; 5 min, 15 % B; 9 min, 15 % B; 9.01 min, 10 % B; 13 min, 10 % B). The multiple reactions monitoring transitions of m/z 360.3 → 242.1, 376.2 → 240.1, 346.2 → 228.2 and 368.2 → 190.2 were opted for quantifying rabeprazole enantiomers, rabeprazole sulfoxide, desmethyl rabeprazole enantiomers and internal standard omeprazole. The analyte samples were prepared by a simple liquid-liquid extraction method. As for the LC-MS method, analytes were separated on a Inertsil® ODS-3 column (4.6 × 150 mm, 5 μm). The mobile phase was acetonitrile-5 mmol/L ammonium acetate water solution (65:35, v/v). ESI+ was used and ion peaks with m/z 344.2 (rabeprazole thioether) and 285.1 (internal standard diazepam) were monitored. Both these 2 methods were validated for specificity, linearity, precision, accuracy, matrix effect and extraction recovery, and, particularly, the stability of analytes under various conditions. We successfully applied these methods to a 13-week toxicokinetic study of rabeprazole in rats after intravenous administration of (R)- (80, 20, 5 mg/kg/d) and racemic (80 mg/kg/d) rabeprazole sodium. The results showed that rabeprazole and its metabolites did not accumulate in rats. However, desmethyl rabeprazole and rabeprazole thioether showed higher exposure and lower clearance rate in the last administration than in the first one. (R)-rabeprazole showed a higher exposure and a slower elimination rate than (S)-rabeprazole in rats. These findings offer experimental evidence and a theoretical foundation for further preclinical investigations and clinical applications of (R)-rabeprazole.

Longitudinal changes in home-based arts engagement during and following the first national lockdown due to the COVID-19 pandemic in the UK

Aims:

This study aimed to examine potential heterogeneity in longitudinal changes in home-based arts engagement during the first national lockdown and following gradual easing of restrictions in the UK. Furthermore, it sought to explore factors that were associated with patterns of longitudinal changes in home-based arts engagement.

Method:

Data were from the UCL COVID-19 Social Study. The analytical sample consisted of 29,147 adults in the UK who were followed up for 22 weeks from 21 March to 21 August 2020. Data were analysed using growth mixture models.

Results:

Our analyses identified five classes of growth trajectories. There were two stable classes showing little change in arts engagement over time (64.4% in total), two classes showing initial increases in arts engagement followed by declines as restrictions were eased (29.8%), and one class showing slight declines during strict lockdown followed by an increase in arts engagement after the easing of restrictions (5.9%). A range of factors were found to be associated with class membership of these arts engagement trajectories, such as age, gender, education, income, employment status, and health.

Conclusion:

There is substantial heterogeneity in longitudinal changes in home-based arts engagement. For participants whose engagement changed over time, growth trajectories of arts engagement were related to changes in lockdown measures. These findings suggest that some individuals may have drawn on the arts when they needed them the most, such as during the strict lockdown period, even if they usually had lower levels of arts engagement before the pandemic. Overall, our results indicate the importance of promoting arts engagement during pandemics and periods of lockdown as part of public health campaigns.

Interventions for treatment of COVID-19: Second edition of a living systematic review with meta-analyses and trial sequential analyses (The LIVING Project)

BACKGROUND

COVID-19 is a rapidly spreading disease that has caused extensive burden to individuals, families, countries, and the world. Effective treatments of COVID-19 are urgently needed. This is the second edition of a living systematic review of randomized clinical trials assessing the effects of all treatment interventions for participants in all age groups with COVID-19.

METHODS AND FINDINGS

We planned to conduct aggregate data meta-analyses, trial sequential analyses, network meta-analysis, and individual patient data meta-analyses. Our systematic review was based on PRISMA and Cochrane guidelines, and our eight-step procedure for better validation of clinical significance of meta-analysis results. We performed both fixed-effect and random-effects meta-analyses. Primary outcomes were all-cause mortality and serious adverse events. Secondary outcomes were admission to intensive care, mechanical ventilation, renal replacement therapy, quality of life, and non-serious adverse events. According to the number of outcome comparisons, we adjusted our threshold for significance to p = 0.033. We used GRADE to assess the certainty of evidence. We searched relevant databases and websites for published and unpublished trials until November 2, 2020. Two reviewers independently extracted data and assessed trial methodology. We included 82 randomized clinical trials enrolling a total of 40,249 participants. 81 out of 82 trials were at overall high risk of bias. Meta-analyses showed no evidence of a difference between corticosteroids versus control on all-cause mortality (risk ratio [RR] 0.89; 95% confidence interval [CI] 0.79 to 1.00; p = 0.05; I2 = 23.1%; eight trials; very low certainty), on serious adverse events (RR 0.89; 95% CI 0.80 to 0.99; p = 0.04; I2 = 39.1%; eight trials; very low certainty), and on mechanical ventilation (RR 0.86; 95% CI 0.55 to 1.33; p = 0.49; I2 = 55.3%; two trials; very low certainty). The fixed-effect meta-analyses showed indications of beneficial effects. Trial sequential analyses showed that the required information size for all three analyses was not reached. Meta-analysis (RR 0.93; 95% CI 0.82 to 1.07; p = 0.31; I2 = 0%; four trials; moderate certainty) and trial sequential analysis (boundary for futility crossed) showed that we could reject that remdesivir versus control reduced the risk of death by 20%. Meta-analysis (RR 0.82; 95% CI 0.68 to 1.00; p = 0.05; I2 = 38.9%; four trials; very low certainty) and trial sequential analysis (required information size not reached) showed no evidence of difference between remdesivir versus control on serious adverse events. Fixed-effect meta-analysis showed indications of a beneficial effect of remdesivir on serious adverse events. Meta-analysis (RR 0.40; 95% CI 0.19 to 0.87; p = 0.02; I2 = 0%; two trials; very low certainty) showed evidence of a beneficial effect of intravenous immunoglobulin versus control on all-cause mortality, but trial sequential analysis (required information size not reached) showed that the result was severely underpowered to confirm or reject realistic intervention effects. Meta-analysis (RR 0.63; 95% CI 0.35 to 1.14; p = 0.12; I2 = 77.4%; five trials; very low certainty) and trial sequential analysis (required information size not reached) showed no evidence of a difference between tocilizumab versus control on serious adverse events. Fixed-effect meta-analysis showed indications of a beneficial effect of tocilizumab on serious adverse events. Meta-analysis (RR 0.70; 95% CI 0.51 to 0.96; p = 0.02; I2 = 0%; three trials; very low certainty) showed evidence of a beneficial effect of tocilizumab versus control on mechanical ventilation, but trial sequential analysis (required information size not reached) showed that the result was severely underpowered to confirm of reject realistic intervention effects. Meta-analysis (RR 0.32; 95% CI 0.15 to 0.69; p < 0.00; I2 = 0%; two trials; very low certainty) showed evidence of a beneficial effect of bromhexine versus standard care on non-serious adverse events, but trial sequential analysis (required information size not reached) showed that the result was severely underpowered to confirm or reject realistic intervention effects. Meta-analyses and trial sequential analyses (boundary for futility crossed) showed that we could reject that hydroxychloroquine versus control reduced the risk of death and serious adverse events by 20%. Meta-analyses and trial sequential analyses (boundary for futility crossed) showed that we could reject that lopinavir-ritonavir versus control reduced the risk of death, serious adverse events, and mechanical ventilation by 20%. All remaining outcome comparisons showed that we did not have enough information to confirm or reject realistic intervention effects. Nine single trials showed statistically significant results on our outcomes, but were underpowered to confirm or reject realistic intervention effects. Due to lack of data, it was not relevant to perform network meta-analysis or possible to perform individual patient data meta-analyses.

CONCLUSIONS

No evidence-based treatment for COVID-19 currently exists. Very low certainty evidence indicates that corticosteroids might reduce the risk of death, serious adverse events, and mechanical ventilation; that remdesivir might reduce the risk of serious adverse events; that intravenous immunoglobin might reduce the risk of death and serious adverse events; that tocilizumab might reduce the risk of serious adverse events and mechanical ventilation; and that bromhexine might reduce the risk of non-serious adverse events. More trials with low risks of bias and random errors are urgently needed. This review will continuously inform best practice in treatment and clinical research of COVID-19.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020178787.

Vaccines to prevent COVID-19: a protocol for a living systematic review with network meta-analysis including individual patient data (The LIVING VACCINE Project)

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19) which has rapidly spread worldwide. Several human randomized clinical trials assessing potential vaccines are currently underway. There is an urgent need for a living systematic review that continuously assesses the beneficial and harmful effects of all available vaccines for COVID-19.

METHODS/DESIGN

We will conduct a living systematic review based on searches of major medical databases (e.g., MEDLINE, EMBASE, CENTRAL) and clinical trial registries from their inception onwards to identify relevant randomized clinical trials. We will update the literature search once a week to continuously assess if new evidence is available. Two review authors will independently extract data and conduct risk of bias assessments. We will include randomized clinical trials comparing any vaccine aiming to prevent COVID-19 (including but not limited to messenger RNA; DNA; non-replicating viral vector; replicating viral vector; inactivated virus; protein subunit; dendritic cell; other vaccines) with any comparator (placebo; "active placebo;" no intervention; standard care; an "active" intervention; another vaccine for COVID-19) for participants in all age groups. Primary outcomes will be all-cause mortality; a diagnosis of COVID-19; and serious adverse events. Secondary outcomes will be quality of life and non-serious adverse events. The living systematic review will include aggregate data meta-analyses, trial sequential analyses, network meta-analyses, and individual patient data meta-analyses. Within-study bias will be assessed using Cochrane risk of bias tool. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) and Confidence in Network Meta-Analysis (CINeMA) approaches will be used to assess certainty of evidence. Observational studies describing harms identified during the search for trials will also be included and described and analyzed separately.

DISCUSSION

COVID-19 has become a pandemic with substantial mortality. A living systematic review assessing the beneficial and harmful effects of different vaccines is urgently needed. This living systematic review will regularly inform best practice in vaccine prevention and clinical research of this highly prevalent disease.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020196492.

Berberine for diarrhea in children and adults: a systematic review and meta-analysis

BACKGROUND

Diarrhea is a ubiquitous digestive system disease, leading to loss of fluid and electrolytes, and may be life-threatening, especially in children and adults who are immunosuppressed or malnourished. Berberine has a broad-spectrum antibiotic activity and is very widely used to treat diarrhea in China. No systematic review has been carried out to evaluate the evidence presented in clinical trials. The aim of this study was to assess the effectiveness and safety of berberine in diarrhea treatment among children and adults.

METHODS

Seven databases and two clinical trial registries were searched on 1 September 2019. Randomized controlled trials were included, where participants were diagnosed (first diagnosed) as having diarrhea according to clear diagnostic criteria. Berberine alone or in combination with Western medication as intervention were included. Subgroup analyses were conducted based on children or adults, acute or persistent diarrhea, infectious or noninfectious and treatment courses. Primary outcomes were clinical cure rate and duration of diarrhea. The GRADE tool was used to assess the quality of evidence.

RESULTS

A total of 38 randomized controlled trials were included involving 3948 participants (including 27 trials on 2702 children) were included. Compared with antibiotics, berberine plus antibiotics showed better results in both adults and in children in general, especially when given for 7 days or 3 days in acute infectious diarrhea of children. Compared with the control groups, using berberine alone or in combination with montmorillonite, probiotics, and vitamin B increased the clinical cure rate of diarrhea. The use of berberine alone or berberine combined with montmorillonite reduced the duration of hospitalization. Using berberine had significantly better laboratory indicators (isoenzyme, inflammatory factors, myocardial enzyme, and fecal trait) and fewer systemic symptoms than the no berberine groups. Overall, 22 of 27 trials on children used berberine as an enema. No deaths and serious adverse events were reported. The quality of evidence of included trials was moderate to low or very low. The impact of different dosages, frequencies and treatment durations on the outcomes was not evaluated due to insufficient number of trials.

CONCLUSION

This review demonstrated that berberine was generally effective in improving clinical cure rates and shortening the duration of diarrhea compared with control groups. No severe adverse event was reported. However, there is still a lack of high-quality evidence for evaluating the efficacy and safety of berberine.

TRIAL REGISTRATION

PROSPERO CRD42020151001 (available from http://www.crd.york.ac.uk/PROSPERO/).

Interventions for treatment of COVID-19: A living systematic review with meta-analyses and trial sequential analyses (The LIVING Project)

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a rapidly spreading disease that has caused extensive burden to individuals, families, countries, and the world. Effective treatments of COVID-19 are urgently needed.

METHODS AND FINDINGS

This is the first edition of a living systematic review of randomized clinical trials comparing the effects of all treatment interventions for participants in all age groups with COVID-19. We planned to conduct aggregate data meta-analyses, trial sequential analyses, network meta-analysis, and individual patient data meta-analyses. Our systematic review is based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) and Cochrane guidelines, and our 8-step procedure for better validation of clinical significance of meta-analysis results. We performed both fixed-effect and random-effects meta-analyses. Primary outcomes were all-cause mortality and serious adverse events. Secondary outcomes were admission to intensive care, mechanical ventilation, renal replacement therapy, quality of life, and nonserious adverse events. We used Grading of Recommendations Assessment, Development and Evaluation (GRADE) to assess the certainty of evidence. We searched relevant databases and websites for published and unpublished trials until August 7, 2020. Two reviewers independently extracted data and assessed trial methodology. We included 33 randomized clinical trials enrolling a total of 13,312 participants. All trials were at overall high risk of bias. We identified one trial randomizing 6,425 participants to dexamethasone versus standard care. This trial showed evidence of a beneficial effect of dexamethasone on all-cause mortality (rate ratio 0.83; 95% confidence interval [CI] 0.75-0.93; p < 0.001; low certainty) and on mechanical ventilation (risk ratio [RR] 0.77; 95% CI 0.62-0.95; p = 0.021; low certainty). It was possible to perform meta-analysis of 10 comparisons. Meta-analysis showed no evidence of a difference between remdesivir versus placebo on all-cause mortality (RR 0.74; 95% CI 0.40-1.37; p = 0.34, I2 = 58%; 2 trials; very low certainty) or nonserious adverse events (RR 0.94; 95% CI 0.80-1.11; p = 0.48, I2 = 29%; 2 trials; low certainty). Meta-analysis showed evidence of a beneficial effect of remdesivir versus placebo on serious adverse events (RR 0.77; 95% CI 0.63-0.94; p = 0.009, I2 = 0%; 2 trials; very low certainty) mainly driven by respiratory failure in one trial. Meta-analyses and trial sequential analyses showed that we could exclude the possibility that hydroxychloroquine versus standard care reduced the risk of all-cause mortality (RR 1.07; 95% CI 0.97-1.19; p = 0.17; I2 = 0%; 7 trials; low certainty) and serious adverse events (RR 1.07; 95% CI 0.96-1.18; p = 0.21; I2 = 0%; 7 trials; low certainty) by 20% or more, and meta-analysis showed evidence of a harmful effect on nonserious adverse events (RR 2.40; 95% CI 2.01-2.87; p < 0.00001; I2 = 90%; 6 trials; very low certainty). Meta-analysis showed no evidence of a difference between lopinavir-ritonavir versus standard care on serious adverse events (RR 0.64; 95% CI 0.39-1.04; p = 0.07, I2 = 0%; 2 trials; very low certainty) or nonserious adverse events (RR 1.14; 95% CI 0.85-1.53; p = 0.38, I2 = 75%; 2 trials; very low certainty). Meta-analysis showed no evidence of a difference between convalescent plasma versus standard care on all-cause mortality (RR 0.60; 95% CI 0.33-1.10; p = 0.10, I2 = 0%; 2 trials; very low certainty). Five single trials showed statistically significant results but were underpowered to confirm or reject realistic intervention effects. None of the remaining trials showed evidence of a difference on our predefined outcomes. Because of the lack of relevant data, it was not possible to perform other meta-analyses, network meta-analysis, or individual patient data meta-analyses. The main limitation of this living review is the paucity of data currently available. Furthermore, the included trials were all at risks of systematic errors and random errors.

CONCLUSIONS

Our results show that dexamethasone and remdesivir might be beneficial for COVID-19 patients, but the certainty of the evidence was low to very low, so more trials are needed. We can exclude the possibility of hydroxychloroquine versus standard care reducing the risk of death and serious adverse events by 20% or more. Otherwise, no evidence-based treatment for COVID-19 currently exists. This review will continuously inform best practice in treatment and clinical research of COVID-19.

Who is lonely in lockdown? Cross-cohort analyses of predictors of loneliness before and during the COVID-19 pandemic

BACKGROUND

There are concerns internationally that lockdown measures taken during the coronavirus disease 2019 (COVID-19) pandemic could lead to a rise in loneliness. As loneliness is recognised as a major public health concern, it is therefore vital that research considers the impact of the current COVID-19 pandemic on loneliness to provide necessary support. But it remains unclear, who is lonely in lockdown?

METHODS

This study compared sociodemographic predictors of loneliness before and during the COVID-19 pandemic using cross-cohort analyses of data from UK adults captured before the pandemic (UK Household Longitudinal Study, n = 31,064) and during the pandemic (UCL (University College London) COVID-19 Social Study, n = 60,341).

RESULTS

Risk factors for loneliness were near identical before and during the pandemic. Young adults, women, people with lower education or income, the economically inactive, people living alone and urban residents had a higher risk of being lonely. Some people who were already at risk of being lonely (e.g. young adults aged 18-30 years, people with low household income and adults living alone) experienced a heightened risk during the COVID-19 pandemic compared with people living before COVID-19 emerged. Furthermore, being a student emerged as a higher risk factor during lockdown than usual.

CONCLUSIONS

Findings suggest that interventions to reduce or prevent loneliness during COVID-19 should be targeted at those sociodemographic groups already identified as high risk in previous research. These groups are likely not just to experience loneliness during the pandemic but potentially to have an even higher risk than normal of experiencing loneliness relative to low-risk groups.

Who is lonely in lockdown? Cross-cohort analyses of predictors of loneliness before and during the COVID-19 pandemic

BACKGROUND

There are concerns internationally that lockdown measures taken during the coronavirus disease 2019 (COVID-19) pandemic could lead to a rise in loneliness. As loneliness is recognised as a major public health concern, it is therefore vital that research considers the impact of the current COVID-19 pandemic on loneliness to provide necessary support. But it remains unclear, who is lonely in lockdown?

METHODS

This study compared sociodemographic predictors of loneliness before and during the COVID-19 pandemic using cross-cohort analyses of data from UK adults captured before the pandemic (UK Household Longitudinal Study, n = 31,064) and during the pandemic (UCL (University College London) COVID-19 Social Study, n = 60,341).

RESULTS

Risk factors for loneliness were near identical before and during the pandemic. Young adults, women, people with lower education or income, the economically inactive, people living alone and urban residents had a higher risk of being lonely. Some people who were already at risk of being lonely (e.g. young adults aged 18-30 years, people with low household income and adults living alone) experienced a heightened risk during the COVID-19 pandemic compared with people living before COVID-19 emerged. Furthermore, being a student emerged as a higher risk factor during lockdown than usual.

CONCLUSIONS

Findings suggest that interventions to reduce or prevent loneliness during COVID-19 should be targeted at those sociodemographic groups already identified as high risk in previous research. These groups are likely not just to experience loneliness during the pandemic but potentially to have an even higher risk than normal of experiencing loneliness relative to low-risk groups.

The Effectiveness of Self-Management of Hypertension in Adults Using Mobile Health: Systematic Review and Meta-Analysis

Background

Effective treatment of hypertension requires careful self-management. With the ongoing development of mobile technologies and the scarcity of health care resources, mobile health (mHealth)–based self-management has become a useful treatment for hypertension, and its effectiveness has been assessed in many trials. However, there is a paucity of comprehensive summaries of the studies using both qualitative and quantitative methods.

Objective

This systematic review aimed to measure the effectiveness of mHealth in improving the self-management of hypertension for adults. The outcome measures were blood pressure (BP), BP control, medication adherence, self-management behavior, and costs.

Methods

A systematic search was conducted using 5 electronic databases. The snowballing method was used to scan the reference lists of relevant studies. Only peer-reviewed randomized controlled trials (RCTs) published between January 2010 and September 2019 were included. Data extraction and quality assessment were performed by 3 researchers independently, adhering to the validation guideline and checklist. Both a meta-analysis and a narrative synthesis were carried out.

Results

A total of 24 studies with 8933 participants were included. Of these, 23 studies reported the clinical outcome of BP, 12 of these provided systolic blood pressure (SBP) and diastolic blood pressure (DBP) data, and 16 articles focused on change in self-management behavior and medication adherence. All 24 studies were included in the narrative synthesis. According to the meta-analysis, a greater reduction in both SBP and DBP was observed in the mHealth intervention groups compared with control groups, −3.78 mm Hg (P<.001; 95% CI −4.67 to −2.89) and −1.57 mm Hg (P<.001; 95% CI −2.28 to −0.86), respectively. Subgroup analyses showed consistent reductions in SBP and DBP across different frequencies of reminders, interactive patterns, intervention functions, and study duration subgroups. A total of 16 studies reported better medication adherence and behavioral change in the intervention groups, while 8 showed no significant change. Six studies included an economic evaluation, which drew inconsistent conclusions. However, potentially long-term financial benefits were mentioned in all economic evaluations. All studies were assessed to be at high risk of bias.

Conclusions

This review found that mHealth self-management interventions were effective in BP control. The outcomes of this review showed improvements in self-management behavior and medication adherence. The most successful mHealth intervention combined the feature of tailored messages, interactive communication, and multifaceted functions. Further research with longer duration and cultural adaptation is necessary. With increasing disease burden from hypertension globally, mHealth offers a potentially effective method for self-management and control of BP. mHealth can be easily integrated into existing health care systems.

Trial Registration

PROSPERO CRD42019152062; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=152062

Overview of the Chromatographic and Mass Spectrometry Analytical Methods for Determination of Lamivudine in Biological Fluids

Background:

Lamivudine was approved by Food and Drug Administration of the United States for the treatment of both HIV and HBV infection, which has been widely used as monotherapy or a component of combination therapy in clinics in many countries and nationalities.

Methods:

In this paper, the recent chromatographic and mass spectrometry analytical methods for the determination of lamivudine individually or combination with other drugs simultaneously were presented. These methods were widely applied in pharmacokinetics studies, bioequivalence studies, therapeutic drug monitoring studies, cell and animal experiments.

Conclusion:

The review paper might provide references for determining lamivudine in biological fluids, the intracorporal process of lamivudine, and the clinical practice by monitoring plasma concentration of lamivudine in the future.

LC-MS for Simultaneous Determination of Vancomycin and Teicoplanin in Patient Plasma and its Application to Therapeutic Drug Monitoring

Background:

Therapeutic drug monitoring is recommended for patients taking vancomycin and teicoplanin to ensure pharmaceutical efficacy and prevent toxicity. Only few studies were reported regarding the simultaneous determination of vancomycin and teicoplanin in human plasma.

Objective:

The study aimed at developing and validating a Liquid Chromatography-Mass Spectrometry (LC-MS) method for simultaneous determination and therapeutic drug monitoring of vancomycin and teicoplanin in patients with severe infection.

Method:

Plasma was processed by protein precipitation extraction. The analytes were separated on a C18 column by gradient elution with 0.1% formic acid and acetonitrile as mobile phase and measured by electrospray ionization source in positive selective ion monitoring mode at m/z 724.7 (vancomycin), 940.7 (teicoplanin) and 329.0 (bergenin). The plasma samples (104) were obtained from patients who were taking vancomycin or teicoplanin for further analysis.

Results:

The calibration curves were linear within the range of 0.25–40 µg/mL for vancomycin, and 0.5-40 µg/mL for teicoplanin. Either inter- or intra-day precision was less than 10.01 %. The extraction recoveries ranged from 89.99 to 94.29% for vancomycin and from 39.83 to 40.16 % for teicoplanin. Vancomycin and teicoplanin in plasma were stable at various storage conditions. The measured mean trough concentrations were 12.313 µg/mL for vancomycin and 8.765 µg/mL for teicoplanin.

Conclusion:

This method was successfully applied to therapeutic drug monitoring of vancomycin and teicoplanin in patients. It is with great clinic value for monitoring and predicting the individual response of patients under treatment.

[Microdeletion and Mutation of Y Chromosome in Full Sibling Identification]

OBJECTIVES

To explore the identification method of full sibling between two males with microdeletion and mutation of Y chromosome.

METHODS

DNA were extracted from two samples. The type testing of Y-STR and autosomal STR were performed. Full sibling between two individuals was calculated by IBS, ITO and discriminant functions methods.

RESULTS

There were 2 loci mutations existed in 33 Y-STR loci and one of the two samples had 19 loci deletions. The IBS of two samples was 53 and greater than the threshold which was 42; FSI was 1.36×10¹⁶ and far greater than 19. The discriminant function of full sibling-unrelated individual D_FS2 was greater than D_R2, which meant the two individuals tend to be full sibling.

CONCLUSIONS

The methods of IBS, ITO and discriminant functions of full sibling-unrelated individual can be used comprehensively to provide more reliable expert opinion in microdeletion and mutation of Y chromosome in full sibling identification.

Determination of brusatol in plasma and tissues by LC-MS method and its application to a pharmacokinetic and distribution study in mice

OBJECTIVES

The quassinoid brusatol, which can be isolated from Brucea javanica (L.) Merr., becomes popularly studied because of its anti-tumor activity. In order to further investigate brusatol and extend its applications, a sensitive analytical method for determination of brusatol in biological samples is essential. However, few methods had been reported until now. In this study, a highly sensitive and reproducible LC-MS method for simultaneous quantification of brusatol in mouse plasma and tissues was developed and validated.

METHOD

Plasma samples and tissue homogenate were extracted with diethyl ether after addition of the internal standard solution(IS). The supernatant was blown to dryness with nitrogen and residual was reconstituted with 100μl of methanol. The separation was performed on an Intersil ODS-3 column and gradient elution was conducted with the mobile phase of water and methanol (0-5min 47:53, 5-5.5min 47:53-10:90, 5.5-9min 10:90, posttime 4min 47:53) at a flow rate of 0.8mL/min. Quantification was performed in the selected ion monitoring (SIM) mode at m/z 543.2 for brusatol and 220.0 for IS (ornidazole). The method was validated by analyzing quality control plasma and tissue homogenate samples, and was applied to analyze samples obtained from mice after injections of brusatol via the tail vein.

RESULTS

With ornidazole as the internal standard, calibration curve of the method ranged from 10 to 320ng/ml for plasma and 10-240ng/ml for tissues. Recovery rate of brusatol from plasma and tissues were between 71.09%-94.91%. Relative standard deviation (RSD) for inter- and intra-day precision was less than 15%, and the accuracy was between 96.1%-111.8%. The pharmacokinetics and distribution study of brusatol in mice after three single doses via the tail vein were carried out based on this method. The concentration of brusatol in plasma decreased rapidly and a more than 10 fold concentration of brusatol was found as compared to that in other tissues.

CONCLUSIONS

This is the first reported LC-MS method for detecting brusatol in tissues and can accurately determine the concentrations of these compounds in plasma and different tissues. Further research on the metabolism of brusatol in vivo is still needed.

Pharmacokinetics of ginkgolide B injection in beagle dogs

A liquid chromatography-mass spectrometry method was developed, validated, and applied to the pharmacokinetic study with doses of 0.68, 2.73 and 10.92 mg/kg of ginkgolide B in beagle dogs after intravenous infusion.An aliquot of blood samples were -collected, separated and quantitatively analyzed by liquid chromatography-mass spectrometry method with mobile phase of acetonitrile-0.02% ammonia solution (33:67, v/v) at a flow rate of 0.8 mL/min on the UltimateTM XB-C18 column (5 μm, 4.6×150 mm).The method was sensitive, accurate and convenient, and can be used for the determination of ginkgolide B in beagle dogs. The Cmax and AUC0-∞ of GB increased with dose escalation, but ANOVA analyses showed that no significant difference was observed in other pharmacokinetic parameters between different doses.An LC/MS method was developed with good sensitivity, reproducibility and specificity. In the pharmacokinetic study of GB in beagle dogs, linear pharmacokinetics was found at doses from 0.62 to 10.92 mg/kg after a single-dose intravenous infusion. Gender differences were not observed in the pharmacokinetics of GB.

[The language healing system of deaf children based on wavelet transform]

In the language healing system of deaf children, the wavelet transform method is employed to describe the time-varying characteristics of speech signals, improve the resolution of speech spectrum and make the speech characteristics more obvious. The speech spectrum information shown in this system is easier for deaf children to observe and understand and it is of great importance to the language healing of deaf children.

[The quantitative analysis of voice disease based on fractal method]

The fractal method is employed to check the voice diseases. The severity of pathological changes of human voice can be analyzed objectively and quantitatively with different fractal dimensions. With this method we can end up the history of judging the voice with subjective hearing and it is of great importance to the development of laryngology.

[Analysis of impulse response of rectangular ultrasound transducer]

A new expression for calculating the impulse response of rectangular pistonlike transducers, proper to any points of acoustic field, is presented. The radiated field of ultrasound transducer can be analyzed using impulse response method, avoiding paraxial and farfield approximation. The velocity potential at an observation point is expressed as the convolution of the excitation velocity and the impulse response. A time-amplitude shift method for the far field impulse response of small aperture transducers is presented. The radiated field of rectangular transducers is calculated through the new method and the previous method and excellent agreement is observed.

Chromatography of human prothrombin from Nitschmann fraction III on DEAE Sepharose Fast Flow using axial and radial flow column

An axial column (3 x 2.6 cm) and a radial flow column (3.5 x 5 cm) packed with DEAE Sepharose Fast Flow media was evaluated for the separation of human prothrombin from Nitschmann fraction III. Under radial flow conditions, a sample flow rate up to 14 mL/min (approximately 18 bed vols/h) was achieved. Breakthrough capacity was determined and both columns had almost the same breakthrough capacity per mL media, indicating that the sample loading was independent of radial column geometry.

Studies on the resuscitative efficacy of polymerized bovine hemoglobin

The paper described modified hemoglobin (Hb) with glycolaldehyde for the efficacy on resuscitation of severe hemorrhagic shock. Our objective was to compare the effect on resuscitation of severe hemorrhagic shock with different experimental groups. Results showed early resuscitation with modified bovine Hb is superior to lactated Ringer's solution group in improving hemodynamic and acidosis, but the effect of polymerized Hb with glycolaldehyde were similar to fresh whole blood in this rat model.

Purification of human prothrombin from Nitschmann fraction III using DEAE membrane radial flow chromatography

A DEAE membrane radial column (4x5 cm) was used to purify human prothrombin from Nitschmann fraction III and performances of the column were investigated. Sample flow-rate of 20-30 ml/min (i.e., 24-36 bed volumes/h) and elution velocity up to 40 ml/min (i.e., 48 bed volumes/h) were obtained without compromising the separation efficiency. Its breakthrough capacity was one-third to half that of the commercial DEAE Sepharose Fast Flow media. It was concluded that the novel column is an attractive alternate to traditional axial column.

[Photodynamic inactivation of model virus in human plasma by methylene blue and its influence on plasma proteins]

OBJECTIVE

To determine whether photochemical method can inactivate viruses in human plasma efficiently, and to what extent it affects the protein in human plasma.

METHODS

Vascular stomatitis virus (VSV) Indiana strain was used as the indicating virus. It was inoculated on Vero cell monolayer, incubated in 37 degrees C for 24 hours, microtitered by cytopathogenic effect. Small amount experiments were carried out to observe virus inactivation and the influence on plasma proteins.

RESULTS

Methylene blue (MB) in combination with visible light can inactivate the model virus in human plasma efficiently. The dye in very low concentration combined with light was sufficient to achieve a reduction of VSV titer of more than 6 log10 TCID50. Compared with the untreated plasma, neither the activities of blood clotting factors nor the immunological properties of the plasma proteins and the blood albumin were reduced significantly. In this experiment, the dose of MB used for photoinactivation of the virus was very low, about a hundred fold lower than that of methemoglobinemia used in clinical treatment. Furthermore, heat of the light and photochemical reaction are two import factors for decreasing of clotting factor's activity.

CONCLUSIONS

The results of this preliminary study suggest the potential application of MB-photodynamic inactivation of plasma virus is an useful approach in clinical practice.

[Antiviral activity of antisense oligonucleotides to human cytomegalovirus]

Human cytomegalovirus(HCMV) is one of the important pathogens to human being. At present there is no specific antiviral drugs. In order to find an effective antisense phosphorothioate deoxyoligonucleotide(ASON) against--HCMV, the antiviral activity was observed in this study. Three ASON complementary to UL36 gene were synthesized according to immediate early gene sequence of HCMV, and the antiviral activity was evaluated in vitro using human embryonic lung cells as targeted cells of virus infections. The result showed that ASON targeting to splice donor had fairly strong antiviral activity. The specific ASON has sure antiviral activity. As a new means, it may be used to prevent and treat human CMV infections.