Interspecies encounters with endemic health conditions: co-producing BVD and lameness with cows and sheep in the north of England

This paper focuses on the relationships between people and farmed nonhuman animals, and between these animals and the farmed environments they encounter, in the enactment of interspecies endemic disease situations. It examines how the nonhuman embodied capacities, agency and subjectivities of cows and sheep on farms in the north of England make a difference to how the endemic conditions of lameness and bovine viral diarrhoea (BVD) are encountered and responded to by farmers and advisers. The paper draws on empirical research with farmers and their advisers, and explores three key, inter-related, themes: first, the importance of intersubjective relationships between people and animals on farms; second, the nonhuman components of the 'disease situations' associated with endemic diseases, including animals' embodied characteristics and behaviours and the relationships between bodies and environments on different farms; and finally the ways in which animal agency and resistance makes a difference to on-farm interventions aiming to prevent or treat lameness and BVD. The paper concludes by arguing that animals' capacities, and nonhuman difference, should be taken further into account in future policy and practice interventions in endemic disease in farmed animals.

Which elements of hospital-based clinical decision support tools for the assessment and management of children with head injury can be adapted for use by paramedics in prehospital care? A systematic mapping review and narrative synthesis

OBJECTIVE

Hospital-based clinical decision tools support clinician decision-making when a child presents to the emergency department with a head injury, particularly regarding CT scanning. However, there is no decision tool to support prehospital clinicians in deciding which head-injured children can safely remain at scene. This study aims to identify clinical decision tools, or constituent elements, which may be adapted for use in prehospital care.

DESIGN

Systematic mapping review and narrative synthesis.

DATA SOURCES

Searches were conducted using MEDLINE, EMBASE, PsycINFO, CINAHL and AMED.

ELIGIBILITY CRITERIA

Quantitative, qualitative, mixed-methods or systematic review research that included a clinical decision support tool for assessing and managing children with head injury.

DATA EXTRACTION AND SYNTHESIS

We systematically identified all in-hospital clinical decision support tools and extracted from these the clinical criteria used in decision-making. We complemented this with a narrative synthesis.

RESULTS

Following de-duplication, 887 articles were identified. After screening titles and abstracts, 710 articles were excluded, leaving 177 full-text articles. Of these, 95 were excluded, yielding 82 studies. A further 14 studies were identified in the literature after cross-checking, totalling 96 analysed studies. 25 relevant in-hospital clinical decision tools were identified, encompassing 67 different clinical criteria, which were grouped into 18 categories.

CONCLUSION

Factors that should be considered for use in a clinical decision tool designed to support paramedics in the assessment and management of children with head injury are: signs of skull fracture; a large, boggy or non-frontal scalp haematoma neurological deficit; Glasgow Coma Score less than 15; prolonged or worsening headache; prolonged loss of consciousness; post-traumatic seizure; amnesia in older children; non-accidental injury; drug or alcohol use; and less than 1 year old. Clinical criteria that require further investigation include mechanism of injury, clotting impairment/anticoagulation, vertigo, length of time of unconsciousness and number of vomits.

Understanding paramedic work in general practice in the UK: a rapid realist synthesis

BACKGROUND

General practice in the UK is under substantial pressure and practices are increasingly including paramedics as part of their workforce. Little is known about how different models of paramedic working may affect successful implementation of the role, as viewed from patient, clinician and system perspectives. This realist synthesis developed theories about 'models of paramedic working in general practice' in different UK contexts to understand their impact.

METHODS

The rapid realist synthesis comprised data from: (1) empirical and grey literature searches; (2) semi-structured realist interviews with system leaders involved with the implementation of the role; and (3) a stakeholder event with healthcare professionals and the public, to develop initial programme theories that can be tested in future work. Sources were analysed using a realist approach that explored the data for novel or causal insights to generate initial programme theories.

RESULTS

Empirical sources (n = 32), grey sources (n = 95), transcripts from system leader interviews (n = 7) and audio summaries from the stakeholder event (n = 22 participants) were synthesised into a single narrative document. The findings confirmed the presence of a wide variety of models of paramedic working in UK general practice. The perceived success of models was influenced by the extent to which the paramedic service was mature and embedded in practice, and according to four theory areas: (1) Primary care staff understanding and acceptance of the paramedic role; (2) Paramedic induction process, including access to training, supervision and development opportunities; (3) Patient understanding and acceptance of the role; (4) Variations in paramedic employment models.

CONCLUSIONS

Variability in how the paramedic role is operating and embedding into general practice across the UK affects the success of the role. These findings provide a theoretical foundation for future research to investigate various 'models of paramedic working' in different contexts.

What factors are associated with ambulance use for non-emergency problems in children? A systematic mapping review and qualitative synthesis

OBJECTIVE

To explore what factors are associated with ambulance use for non-emergency problems in children.

METHODS

This study is a systematic mapping review and qualitative synthesis of published journal articles and grey literature. Searches were conducted on the following databases, for articles published between January 1980 and July 2020: MEDLINE, EMBASE, PsycINFO, CINAHL and AMED. A Google Scholar and a Web of Science search were undertaken to identify reports or proceedings not indexed in the above. Book chapters and theses were searched via the OpenSigle, EThOS and DART databases. A literature advisory group, including experts in the field, were contacted for relevant grey literature and unpublished reports. The inclusion criteria incorporated articles published in the English language reporting findings for the reasons behind why there are so many calls to the ambulance service for non-urgent problems in children. Data extraction was divided into two stages: extraction of data to generate a broad systematic literature 'map', and extraction of data from highly relevant papers using qualitative methods to undertake a focused qualitative synthesis. An initial table of themes associated with reasons for non-emergency calls to the ambulance for children formed the 'thematic map' element. The uniting feature running through all of the identified themes was the determination of 'inappropriateness' or 'appropriateness' of an ambulance call out, which was then adopted as the concept of focus for our qualitative synthesis.

RESULTS

There were 27 articles used in the systematic mapping review and 17 in the qualitative synthesis stage of the review. Four themes were developed in the systematic mapping stage: socioeconomic status/geographical location, practical reasons, fear of consequences and parental education. Three analytical themes were developed in the qualitative synthesis stage including practicalities and logistics of obtaining care, arbitrary scoring system and retrospection.

CONCLUSIONS

There is a lack of public and caregiver understanding about the use of ambulances for paediatrics. There are factors that appear specific to choosing ambulance care for children that are not so prominent in adults (fever, reassurance, fear of consequences). Future areas for attention to decrease ambulance activation for paediatric low-acuity reports were highlighted as: identifying strategies for helping caregivers to mitigate perceived risk, increasing availability of primary care, targeted education to particular geographical areas, education to first-time parents with infants and providing alternate means of transportation.

PROSPERO REGISTRATION NUMBER

CRD42019160395.

PP20 Paramedic identification and referral of patients in the last year of life: a stakeholder interview study

Background

Patients are approaching End of Life when they are likely to die within the next 12 months. Quality in End of Life Care is variable and identifying patients in the End of Life phase is challenging, particularly in those people with diagnoses other than cancer. Many patients accessing the ambulance service are in the last year of their lives and the role of ambulance services in recognising patients approaching the end of their lives is often overlooked. Patients who are End of Life should be offered advanced care planning.

Research Question

What are stakeholders’ views on a paramedic screening and referral intervention aimed at improving care planning in patients in the last year of life?

Methods

A qualitative study using semi-structured telephone interviews conducted with 17 stakeholders to investigate stakeholders’ views on:

the utility of a paramedic screening and referral tool

the likely impact of a paramedic screening and referral tool

Preliminary Results

All staff groups:

Increasing advanced care planning would be advantageous for patients

Patients with non-malignant conditions are not readily recognised as End of Life.

Paramedics should use the Gold Standards Framework Proactive Identification Guidance to identify patients in the last year of life.

The proposed intervention has the potential to reduce unnecessary hospital admissions and unnecessary resuscitation.

Specific staff groups:

GPs: Concerns about additional workload.

GPs: The intervention is useful for patients who may ‘fall under the radar’.

GPs and ED doctors: Concerns about the need for paramedics to have sensitive communication skills.

Paramedics and GPs: A dedicated End of Life lead or team would be advantageous.

Conclusions

The introduction of an end of life screening and referral tool into paramedic practice is a welcome intervention and will have a positive impact on patients at the end of life. GPs expressed concern about capacity to manage referrals.

Distribution of Lesions in Fetal Brains Following Experimental Infection of Pregnant Sheep With Toxoplasma gondii

Six ovine fetal brains were harvested 33 to 35 days postchallenge from 5 ewes, each of which was given 3000 Toxoplasma gondii oocysts on day 90 of pregnancy. Histopathologic examination of transverse sections taken at 13 levels in the fetal brains revealed the presence of toxoplasmosis-related lesions in all 6 brains. However, lesions were not randomly distributed ( P = .007); they were most numerous at the level of the optic tract, the rostral margin of the pons, and 4 mm caudal to the ansate sulcus and were absent in all sections at the level of the caudal cerebellum. Lesion distribution may be due to hemodynamic factors, differences in the expression of endothelial surface receptor molecules at the level of the blood-brain barrier, or the presence of localized permissive/inhibitory factors within the brain. The results have implications for the selection of areas of brain from aborted ovine fetuses to be examined histopathologically for laboratory diagnosis.

A first in man, phase I dose-escalation study of PHA-793887, an inhibitor of multiple cyclin-dependent kinases (CDK2, 1 and 4) reveals unexpected hepatotoxicity in patients with solid tumors

BACKGROUND

PHA-793887 is an inhibitor of multiple cyclin dependent kinases (CDK) with activity against CDK2, CDK1 and CDK4. The primary objectives of this first in man study were to determine the dose limiting toxicities (DLTs), maximum tolerated dose (MTD) and recommended phase II dose of PHA-793887.

RESULTS

Although toxicity was acceptable at initial dose levels, PHA-793887 was poorly tolerated at doses ≥44 mg/m2. The most frequent events across all dose levels were gastrointestinal or nervous system events. DLTs were experienced by two of three patients at the dose level of 66 mg/m2, and by three of nine patients at the dose level of 44 mg/m2. In all but one patient the DLT was hepatotoxicity; fatal hepatorenal failure was seen in one patient treated at the 44 mg/ m2 dose level. There were no objective responses, but disease stabilization was observed in five patients. Over the dose range investigated, pharmacokinetic studies showed that systemic exposure to PHA-793887 increased with the dose and was time-independent. The study terminated after the enrolment of 19 patients due to the severe hepatic toxicity.

PATIENTS AND METHODS

Cohorts of three to six patients were treated at doses of 11, 22, 44 and 66 mg/m2 of PHA-793887 administered as 1-hour intravenous infusion on days 1, 8 and 15 in a 4-week cycle. Safety and pharmacokinetics were investigated.

CONCLUSION

PHA-793887 induces severe, dose-related hepatic toxicity, which was not predicted by pre-clinical models and currently precludes its further clinical development.

Building trans-Atlantic graduate education programs in biorenewable resources

We are now faced with increasingly expensive motor fuels and agriculture has potential to partially relieve these pressures. The 2007 U.S. Energy Independence and Security Act calls for the U.S. to replace with renewable fuels about 36 billion gallons of its annual 150 billion gallon motor fuel consumption by 2022. This is a monumental task that can only be achieved by conducting innovative research to discover breakthrough technologies and by educating scientists and engineers around the world. Three European and three U.S. institutions have forged partnerships that have enabled 4-6 month graduate student and faculty exchanges, faculty and graduate student participation in two-week intensive courses in both the E.U. and U.S., and sharing of educational materials. With two years to go on a second grant, 23 U.S. students have been sent to the E.U. for 4-6 months and the E.U. has sent 29 students to the U.S. Another 38 U.S. students and 36 faculty have participated in two-week intensive programs in Europe; and five E.U. students and two faculty came to the U.S. to learn and teach, respectively, in our intensive program.

Regional variation of airway hyperresponsiveness in children with asthma

Families with asthmatic children were recruited to take part in a multi-centre collaborative study into the genetics of asthma. Detailed phenotypic information was collected on all family members including: lung function, anthropomorphic measurements, response to methacholine challenge, skin prick testing, serum IgE measurements and a detailed nurse-administered questionnaire. Families were eligible for entry into the study if they had two children with a doctor-diagnosis of asthma. Bennett/Twin nebulisers were supplied to each centre from a single source and these were calibrated to determine gravimetric nebuliser output prior to use. Asthmatic probands from each centre had similar degrees of asthma severity and atopy. There was no significant difference in the sex ratios or ages of the probands or numbers of parents with a history of smoking in the families recruited at each centre. However, there was a significant difference in the number of children with airway hyperresponsiveness, with 90% of the North Staffordshire group but only 60% of the Sheffield group having a PC20 of <8 mg/ml for methacholine. This difference highlights the difficulty of using families from different centres in genetic and epidemiological studies.

Photochemical production of conjugated linoleic acid from soybean oil

Conjugated linoleic acid (CLA), an anticarcinogenic compound with numerous other health benefits, is present mainly in dairy and beef lipids. The main CLA isomer present in dairy and beef lipids is cis 9, trans 11 CLA at a 0.5% concentration. The typical minimum human dietary intake of CLA is 10 times less than the 3 g/d suggested requirement that has been extrapolated from animal and cell-line studies. The objectives of this study were to produce CLA isomers from soybean oil by photoisomerization of soybean oil linoleic acid and to study the oxidation status of the oil. Refined, bleached, and deodorized soybean oil with added iodine concentrations of 0, 0.1, 0.25, and 0.5% was exposed to a 100-W mercury lamp for 0 to 120 h. An SP-2560 fused-silica capillary GC column with FID was used to analyze the esterified CLA isomers in the photoisomerized oil. The CLA content of the individual isomers was optimized by response surface methodology. Attenuated total reflectance (ATR)-FTIR spectra in the 3400 to 3600 cm(-1) range and 1H NMR spectra in the 8 to 12 ppm range of the photoisomerized soybean oil were obtained to follow hydroperoxide formation. The largest amount of cis 9, trans 11 CLA isomer in soybean oil was 0.6%, obtained with 0.25% iodine and 84 h of photoisomerization. Lipid hydroperoxide peaks in the ATR-FTIR spectra and aldehyde peaks in the 1H NMR spectra were not observed in the photoisomerized soybean oil, and the spectra were similar to that of fresh soybean oil. This study shows that CLA isomers can be produced simply and inexpensively from soybean oil by photoisomerization.

An improved method for production of silica from rice hull ash

Rice hull ash (RHA) contains over 60% silica and can be an economically viable raw material for the production of silica based products. A previously published method for producing silica xerogel involved dissolving RHA silica with alkali solution to form sodium silicate solution and subsequently forming silica aquagel by adding hydrochloric acid to lower the pH from 11.8 to 7.0, followed by washing and drying aquagel to form xerogel. The silica xerogel had over 4% sodium as a contaminant. An improved method to produce silica xerogel with lower sodium is described in this study. The improved method involved production of silica aquagel by adding silicate solution to pH 1.5 hydrochloric, citric, or oxalic acid solutions until the pH 4.0 was reached. The aquagel was washed and dried to form silica xerogel. For comparison silica xerogels were also produced at pH 7.0 by the published method. X-ray photoelectron spectroscopy was used to determine the elemental content of silica xerogels. The silica, sodium, carbon and oxygen content of silica xerogels varied depending on the pH and the type of acid used for the production of these xerogels. Silica xerogels produced by the improved method using citric and oxalic acid had sodium content of 0.52% and 0.22%, respectively.

The validity of cognitive distance in oral and written discourse

Oral and written discourse samples of adolescents with closed head injury (CHI) and controls were analyzed to determine if efficiency and coherence measures changed as the length of their picture descriptions increased. The hypothesis was that as ideas were elaborated, the number of words used to express an idea would increase and the conceptual connectedness of ideas would decrease. This research study supported this expectation for efficiency in normal oral and written discourse but not for the discourse of participants with CHI. Further, the efficiency measure significantly differentiated the writing and speaking of the two groups as the picture descriptions were elaborated. Coherence ratings did not distinguish the development of discourse within or between groups

Improved method for determination of pectin degree of esterification by diffuse reflectance Fourier transform infrared spectroscopy

An improved method for the determination of pectin degree of esterification (DE) by diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) was developed. Pectin samples with a range of DE as determined by gas chromatography were used for developing a calibration curve by DRIFTS. A linear relationship between the DE of pectin standards and FTIR peak ratio for ester carboxyl peak area to total carboxyl peak area was found (R(2) = 0.97). Pectin DE of various samples was calculated from the linear fit equation developed by DRIFTS. Accuracy of the DRIFTS method was determined by comparing the DE values of four commercial pectins obtained by DRIFTS methods to the values obtained by the gas chromatography method. Greater precision was obtained for the FTIR measurement of test pectin samples when the ester peak ratio was used relative to the ester peak area.

Increasing prevalence of asthma diagnosis and symptoms in children is confined to mild symptoms

BACKGROUND

The prevalence of childhood asthma is increasing but few studies have investigated trends in asthma severity. We investigated trends in asthma diagnosis and symptom morbidity between an eight year time period in a paired prevalence study.

METHODS

All children in one single school year aged 8-9 years in the city of Sheffield were given a parent respondent questionnaire in 1991 and 1999 based on questions from the International Survey of Asthma and Allergy in Children (ISAAC). Data were obtained regarding the prevalence of asthma and wheeze and current (12 month) prevalences of wheeze attacks, speech limiting wheeze, nocturnal cough and wheeze, and exertional symptoms.

RESULTS

The response rates in 1991 and 1999 were 4580/5321 (85.3%) and 5011/6021 (83.2%), respectively. There were significant increases between the two surveys in the prevalence of asthma ever (19.9% v 29.7%, mean difference 11.9%, 95% confidence interval (CI) 10.16 to 13.57, p<0.001), current asthma (10.3% v 13.0%, mean difference 2.7%, 95% CI 1.44 to 4.03, p<0.001), wheeze ever (30.3% v 35.8%, mean difference 5.7%, 95% CI 3.76 to 7.56, p<0.001), wheeze in the previous 12 months (17.0% v 19.4%, mean difference 2.5, 95% CI 0.95 to 4.07, p<0.01), and reporting of medication use (16.9% v 20%, mean difference 3.0%, 95% CI 1.46 to 4.62, p<0.001). There were also significant increases in reported hayfever and eczema diagnoses.

CONCLUSIONS

Diagnostic labelling of asthma and lifetime prevalence of wheeze has increased. The current 12 month point prevalence of wheeze has increased but this is confined to occasional symptoms. The increased medication rate may be responsible for the static prevalence of severe asthma symptoms. The significant proportion of children receiving medication but reporting no asthma symptoms identified from our 1999 survey suggests that some children are being inappropriately treated or overtreated.

Executive function and verbal working memory in adolescents with closed head injury (CHI)

The relationship between executive function (EF) and working memory (WM) was studied in eight adolescents with closed head injury (CHI) and eight controls, matched for age, gender and socioeconomic status (SES). A cognitive-linguistic test (Scales of Cognitive Ability for Traumatic Brain Injury, SCATBI) was used to group CHI participants by seventy. EF was tested with a measure of daily functioning (Pro-Ex) and WM was tested with a recognition memory task (RMT). When all subject test data were grouped, a positive linear correlation was found for the Pro-Ex and the RMT. A strong-to-moderate positive correlation was found for components of the EF measure and the RMT. Severity of injury influenced test performance for both the EF and WM measures, with a significance between group effects found on the RMT task. Results indicate a relationship between executive function and working memory, severity of injury and test performance and the need to assess EF of CHI adolescents with a measure of daily functioning.

Oral and written discourse in adolescents with closed head injury

Analysis of oral and written discourse suggested differing cognitive demands for modes of expression. Verbal samples were provided by 8 adolescents with closed head injury (CHI) and 8 controls. A generation task using a picture stimulus was the basis for discourse. Eight measures [productivity, efficiency, semantic ties (lexical, incomplete, elliptical), maze use, coherence (global, local)] were utilized. A covariate model consisting of group membership (CHI vs control), executive functioning and working memory helps to explain variance in the discourse skills of adolescents with CHI.

Automation of data collection for matrix-assisted laser desorption/ionization mass spectrometry using a correlative analysis algorithm

Automation of data collection in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry using a correlative analysis algorithm is demonstrated. This algorithm was employed to compensate for mass spectral jittering in MALDI data collection (e.g., peak shifts along the m/z axis, signal intensity deviations, etc.). Several important parameters for performing correlative analysis, such as the minimum correlation coefficient to be used and number of mass spectra to acquire prior to correlation, have been investigated and optimized. In addition, the correlation algorithm improved mass resolution of low- and high-molecular-weight compounds by as much as a factor of 4. Signal reproducibility in MALDI quantitative analysis also is improved when correlation is employed for data collection. This data collection algorithm can be used in conjunction with other instrumental optimization programs to allow for fully automated MALDI analysis, which is required for the routine applications carried out in many analytical laboratories.

Maintaining patient endurance. The comfort work of trauma nurses

The purpose of this article is to explicate patterns of comforting that assist the seriously injured patient to endure the pain of injury and subsequent treatments and to remain controlled. The care provided to 67 trauma patients in two trauma centers was videotaped and analyzed using observational methods and linguistic analysis. During painful procedures, when patients exhibited extreme distress, one nurse usually assumed the role of comforter. The nurses used a patterned mode of speech ("comfort talk"), touch, and distinctive posturing behaviors that enabled the patient to endure the agony and maintain control. In this article, the authors describe the comfort work of nursing in emerging situations, further develop the Comfort Talk Register, and describe the concomitant behaviors that facilitate patient endurance. They suggest that the comfort work of nurses in this situation enables patients to endure and reduces shock and posttraumatic stress following trauma care.

Sounds of comfort in the trauma center: how nurses talk to patients in pain

Language that trauma center nurses directed to 29 distressed patients was systematically examined from videotaped data. A unique set of co-occurring linguistic features and intonation patterns which characterize the comfort talk register was identified. Descriptive data reveal that nurses reserve this register for patients only and that linguistic adjustments are made within the register for children. The nurses' comfort talk register is also characterized by a restricted set of pragmatic functions which include: (1) helping patients to 'hold on'; (2) obtaining information that contributes to the assessment of the patient's condition; (3) giving and receiving information about procedures; and (4) verbally communicating a sense of caring to the patient. Other grammatical and lexical features that are used in conjunction with selected intonation contours which delineate the nurse's comfort talk register are discussed relative to interactional processes.

Direct quantitative analysis of peptides using matrix assisted laser desorption ionization

The protocol and various matrices were examined for quantification of biomolecules in both the low ca. 1200 amu and mid mass 6000-12000 amu ranges using an internal standard. Comparative studies of different matrices of MALDI quantitative analysis showed that the best accuracy and standard curve linearity were obtained for two matrices: (a) 2,5-dihydroxybenzoic acid (DHB) combined with a comatrix of fucose and 5-methoxysalicylic acid (MSA) and (b) ferulic acid/fucose. In the low mass range, the quantitative limit was in the 30 fmol range and in the mid mass range the quantitative limit was in the 250 fmol range. Linear response was observed over 2-3 decades of analyte concentration. The relative error of the standard curve slope was 1.3-1.8% with correlation coefficients of 0.996-0.998.The main problem for quantitative measurement was suppression of the signal of the less concentrated component (analyte or internal standard) by the more concentrated component. The effect was identified with saturation of the matrix by the analyte. The threshold of matrix saturation was found to be in the range of 1/(3000-5000) analyte/matrix molar ratio. To avoid matrix saturation the (analyte+internal standard) to matrix molar ratio should be below this threshold. Thus the internal standard concentration should be as low as possible.DHB/MSA/fucose and ferulic acid/fucose matrices demonstrated good accuracy and linearity for standard curves even when the internal standard had chemical properties different from the analyte. However, use of an internal standard with different chemical properties requires highly stable instrumental parameters as well as constant (analyte+internal standard)/matrix molar ratio for all samples.

A quantitative study of in vitro hepatic metabolism of tacrolimus (FK506) using secondary ion and matrix-assisted laser desorption/ionization mass spectrometry

The identification and simultaneous quantification of Tacrolimus and its hepatic metabolites in baboons has been achieved using matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry and static secondary-ion mass spectrometry (TOF-SIMS). Little fragmentation, high sensitivity and tolerance to contamination are the major advantages of these methods, allowing facile identification and quantification of metabolites produced in vitro with minor analyte isolation. Based on the MALDI and TOF-SIMS results, seven metabolites have been identified: de-methylated, di de-methylated, hydroxylated, di hydroxylated, de-methylated hydroxylated, dihydrodiol, and di de-methylated hydroxylated. The concentrations of the parent drug and its major metabolites (e.g. de-methylated, di de-methylated) were measured using Rapamycin as an internal standard. The time course of Tacrolimus and its major metabolites as a function of incubation time was calculated. Good correlation between SIMS and MALDI results was obtained.

Application of the fast-evaporation sample preparation method for improving quantification of angiotensin II by matrix-assisted laser desorption/ionization

The fast-evaporation method of sample preparation has been applied for quantitative analysis using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. An instrumental protocol focusing on improvement of shot-to-shot repeatability and compensation for signal degradation has been developed for quantification of angiotensin II using the fast-evaporation technique and an internal standard. The fast-evaporation method was compared to the standard method of sample preparation (using a multicomponent matrix) in the quantitative analysis of angiotensin II, and found to be superior in several respects. Improvement in sample homogeneity using the fast-evaporation method enhanced both point-to-point repeatibility and sample-to-sample reproducibility. The relative standard deviations of the analyte/internal standard ratios (point RSD) were decreased by a factor of three compared to those obtained using the multicomponent matrix method. The average point RSD was found to be ca. 5% for the fast-evaporation technique. Two internal standards were evaluated for quantification of angiotensin II. The better one, 1-SAR-8-Ile angiotensin II, yielded a relative standard deviation of the standard curve slope of ca. 2.2% over two orders of magnitude of concentration (45 nM to 3000 nM), an improvement by a factor of two over the standard preparation method. Renal microdialysate samples, spiked with angiotensin II and the internal standard 1-SAR-8-Ile angiotensin II, were also analyzed using the fast-evaporation technique. The detection limit was calculated to be in the high attomole range (675 amol). Furthermore, the accuracy for a single determination of angiotensin II concentration in these samples was found to be 13.9% with a relative error of 8.19%.