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Background: Community pharmacists have an important role to play in providing medication adherence support (MAS) to older patients. However, research has shown that pharmacists rarely ask patients about adherence and offer limited solutions. The Theoretical Domains Framework (TDF) can guide the selection of behaviour change techniques (BCTs), to enhance behaviours such as MAS provision., Objectives: This study aimed to: (1) explore barriers/facilitators influencing community pharmacists' provision of MAS to older patients prescribed multiple medications; (2) Identify theoretical domains to target for behaviour change; (3) Select BCTs to deliver to pharmacists to enhance MAS provision., Method: As part of a two-phase study, semi-structured interviews and a cross-sectional survey were conducted. In Phase 1, community pharmacists in Northern Ireland (NI) were recruited using purposive/snowball sampling. TDF-based interviews were audio-recorded, transcribed and analysed by two independent researchers using the framework method/content analysis. In Phase 2, a TDF-based postal survey was mailed to all community pharmacies in NI (n = 521) and analysed using descriptive statistics. Triangulated findings informed selection of target TDF domains and BCTs to deliver to enhance MAS provision., Results: Fifteen pharmacists were interviewed for Phase 1. Barriers and facilitators included inadequate remuneration, time and knowledge of solutions and professional confidence. In Phase 2, 143 (27.4%) survey responses were received. Potential barriers included inadequate training in motivational techniques and difficulties with decision-making. Based on triangulated findings, seven domains (e.g. skills, motivation/goals) were identified as targets and mapped across to 18 BCTs (e.g. behavioural practice/rehearsal, prompts/cues)., Conclusions: This mixed methods study provides unique perspectives on the wide range of barriers/facilitators that are perceived to influence the provision of MAS by community pharmacists. The 18 BCTs identified to target each of the seven key target domains identified in this study will be tested in a future pilot study of a patient-targeted intervention., (Copyright © 2020. Published by Elsevier Inc.)

Background: Older patients prescribed multiple medications commonly experience difficulties with adherence. High-quality evidence on interventions targeting older patients is lacking. Theory is rarely used to tailor adherence solutions. This study aimed to pilot test a novel intervention, developed using the Theoretical Domains Framework, which guides community pharmacists in identifying adherence barriers and delivering tailored solutions (behaviour change techniques). Key study procedures (e.g. recruitment, data collection) for a future randomised controlled trial (cRCT) were also assessed., Methods: Using purposive sampling, this non-randomised pilot study aimed to recruit 12 community pharmacies (six in Northern Ireland; six in London, England). Pharmacists were trained to deliver the intervention to non-adherent older patients (maximum 10 per pharmacy; target n = 60-120) aged ≥ 65 years (reduced to 50 years due to recruitment challenges) and prescribed ≥ 4 regular medicines. The intervention, guided by an iPad web-application, was delivered over 3-4 face-to-face or telephone sessions, tailored to specific barriers to adherence. We assessed the feasibility of collecting adherence data (primary outcome: self-report and dispensing records), health-related quality of life (HRQOL) and unplanned hospitalisations (secondary outcomes) at baseline and 6-months. The final decision on progressing to a cRCT, using pre-defined 'stop-amend-go' criteria, is presented., Results: Fifteen pharmacists from 12 pharmacies were recruited and trained. One pharmacy subsequently dropped out. Sixty patients were recruited (meeting the 'Amend' progression criteria), with 56 receiving the intervention. Adherence barriers were identified for 55 patients (98%) and a wide range of behaviour change solutions delivered (median: 5 per patient). Self-report and dispensing adherence data were available for 37 (61.7%) and 44 (73.3%) patients, respectively. HRQOL data were available for 35 (58.3%) patients. GP-reported and self-reported hospitalisations data were available for 47 (78.3%) and 23 (38.3%) patients, respectively. All progression concepts were met (nine 'Go' and three 'Amend' criteria)., Conclusion: This study demonstrates the feasibility of key study procedures (e.g. pharmacy recruitment) and delivery of a tailored adherence intervention in community pharmacies. However, modifications are required to enhance issues identified with patient recruitment, retention and missing data. A future definitive cRCT will explore the effectiveness of the intervention., Trial Registration: ISRCTN, ISRCTN73831533 , Registered 12 January 2018.

Background: To improve the effectiveness of interventions targeting non-adherence in older adults, a systematic approach to intervention design is required. The content of complex interventions and design decisions are often poorly described in published reports which makes it difficult to explore why they are ineffective. This intervention development study reports on the design of a community pharmacy-based adherence intervention using 11 Behaviour Change Techniques (BCTs) which were identified from previous qualitative research with older patients using the Theoretical Domains Framework., Methods: Using a group consensus approach, a five-step design process was employed. This focused on decisions regarding: (1) the overall delivery format, (2) formats for delivering each BCT; (3) methods for tailoring BCTs to individual patients; (4) intervention structure; and (5) materials to support intervention delivery. The APEASE (Affordability; Practicability; Effectiveness/cost-effectiveness; Acceptability; Side effects/safety; Equity) criteria guided the selection of BCT delivery formats., Results: Formats for delivering the 11 BCTs were agreed upon, for example, a paper medicines diary was selected to deliver the BCT 'Self-monitoring of behaviour'. To help tailor the intervention, BCTs were categorised into 'Core' and 'Optional' BCTs. For example, 'Feedback on behaviour' and 'Action planning' were selected as 'Core' BCTs (delivered to all patients), whereas 'Prompts and cues' and 'Health consequences' were selected as 'Optional' BCTs. A paper-based adherence assessment tool was designed to guide intervention tailoring by mapping from identified adherence problems to BCTs. The intervention was designed for delivery over three appointments in the pharmacy including an adherence assessment at Appointment 1 and BCT delivery at Appointments 2 and 3., Conclusions: This paper details key decision-making processes involved in moving from a list of BCTs through to a complex intervention package which aims to improve older patients' medication adherence. A novel approach to tailoring the content of a complex adherence intervention using 'Core' and 'Optional' BCT categories is also presented. The intervention is now ready for testing in a feasibility study with community pharmacists and patients to refine the content. It is hoped that this detailed report of the intervention content/design process will allow others to better interpret the future findings of this work.

Background: Adhering to multiple medications as prescribed is challenging for older patients (aged ≥ 65 years) and a difficult behaviour to improve. Previous interventions designed to address this have been largely complex in nature but have shown limited effectiveness and have rarely used theory in their design. It has been recognised that theory ('a systematic way of understanding events or situations') can guide intervention development and help researchers better understand how complex adherence interventions work. This pilot study aims to test a novel community pharmacy-based intervention that has been systematically developed using the Theoretical Domains Framework (12-domain version) of behaviour change., Methods: As part of a non-randomised pilot study, pharmacists in 12 community pharmacies across Northern Ireland ( n  = 6) and London, England ( n  = 6), will be trained to deliver the intervention to older patients who are prescribed ≥ 4 regular medicines and are non-adherent (self-reported). Ten patients will be recruited per pharmacy ( n  = 120) and offered up to four tailored one-to-one sessions, in the pharmacy or via telephone depending on their adherence, over a 3-4-month period. Guided by an electronic application (app) on iPads, the intervention content will be tailored to each patient's underlying reasons for non-adherence and mapped to the most appropriate solutions using established behaviour change techniques. This study will assess the feasibility of collecting data on the primary outcome of medication adherence (self-report and dispensing data) and secondary outcomes (health-related quality of life and unplanned hospitalisations). An embedded process evaluation will assess training fidelity for pharmacy staff, intervention fidelity, acceptability to patients and pharmacists and the intervention's mechanism of action. Process evaluation data will include audio-recordings of training workshops, intervention sessions, feedback interviews and patient surveys. Analysis will be largely descriptive., Discussion: Using pre-defined progression criteria, the findings from this pilot study will guide the decision whether to proceed to a cluster randomised controlled trial to test the effectiveness of the S-MAP intervention in comparison to usual care in community pharmacies. The study will also explore how the intervention components may work to bring about change in older patients' adherence behaviour and guide further refinement of the intervention and study procedures., Trial Registration: This study is registered at ISRCTN: 10.1186/ISRCTN73831533., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s). 2019.)

Background: Medication adherence is vital to ensuring optimal patient outcomes, particularly amongst multimorbid older people prescribed multiple medications. Interventions targeting adherence often lack a theoretical underpinning and this may impact on effectiveness. The theoretical domains framework (TDF) of behaviour can aid intervention development by systematically identifying key determinants of medication adherence., Objectives: This study aimed to (i) identify determinants (barriers, facilitators) of adherence to multiple medications from older people's perspectives; (ii) identify key domains to target for behaviour change; and (iii) map key domains to intervention components [behaviour change techniques (BCTs)] that could be delivered in an intervention by community pharmacists., Method: Focus groups were conducted with older people (>65 years) receiving ≥4 medications. Questions explored the 12 domains of the TDF (eg "Knowledge," "Emotion"). Data were analysed using the framework method and content analysis. Identification of key domains and mapping to intervention components (BCTs) followed established methods., Results: Seven focus groups were convened (50 participants). A wide range of determinants were identified as barriers (eg forgetfulness, prioritization of medications) and facilitators (eg social support, personalized routines) of adherence to multiple medications. Eight domains were identified as key targets for behaviour change (eg "Social influences," "Memory, attention and decision processes," "Motivation and goals") and mapped to 11 intervention components (BCTs) to include in an intervention [eg "Social support or encouragement (general)," "Self-monitoring of the behaviour," "Goal-setting (behaviour)"]., Conclusion: This study used a theoretical underpinning to identify potential intervention components (BCTs). Future work will incorporate the selected BCTs into an intervention that will undergo feasibility testing in community pharmacies., (© 2017 The Authors Health Expectations Published by John Wiley & Sons Ltd.)

Background: Previous interventions have shown limited success in improving medication adherence in older adults, and this may be due to the lack of a theoretical underpinning., Objective: This review sought to determine the effectiveness of theory-based interventions aimed at improving medication adherence in older adults prescribed polypharmacy and to explore the extent to which psychological theory informed their development., Data Sources: Eight electronic databases were searched from inception to March 2015, and extensive hand-searching was conducted., Eligibility Criteria: Interventions delivered to older adults (populations with a mean/median age of ≥65 years) prescribed polypharmacy (four or more regular oral/non-oral medicines) were eligible. Studies had to report an underpinning theory and measure at least one adherence and one clinical/humanistic outcome., Review Methods: Data were extracted independently by two reviewers and included details of intervention content, delivery, providers, participants, outcomes and theories used. The theory coding scheme (TCS) was used to assess the extent of theory use., Results: Five studies cited theory as the basis for intervention development (social cognitive theory, health belief model, transtheoretical model, self-regulation model). The extent of theory use and intervention effectiveness in terms of adherence and clinical/humanistic outcomes varied across studies. No study made optimal use of theory as recommended in the TCS., Conclusions: The heterogeneity observed and inclusion of pilot designs mean conclusions regarding effectiveness of theory-based interventions targeting older adults prescribed polypharmacy could not be drawn. Further primary research involving theory as a central component of intervention development is required. The review findings will help inform the design of future theory-based adherence interventions., Competing Interests: Compliance with Ethical StandardsFundingThis work was supported by The Dunhill Medical Trust (Grant Number: R298/0513). The funding body was not involved in the design of the review, data collection, analysis and interpretation of findings or in writing the manuscript.Conflict of interestDeborah Patton, Carmel Hughes, Cathal Cadogan and Cristín Ryan have no conflicts of interest relevant to the content of this review.

Purpose: Youth living with human immunodeficiency virus (HIV) account for over one third of new HIV infections and are at high risk of adverse psychosocial, everyday living, and health outcomes. Human immunodeficiency virus-associated neurocognitive disorders (HAND) are known to affect health outcomes of HIV-infected adults even in the era of combination antiretroviral therapy. Thus, the current study aimed to characterize the prevalence and clinical correlates of HAND in youth living with HIV. Here, we report baseline neurocognitive data for behaviorally HIV-infected youth enrolled in a prospective study evaluating strategies of antiretroviral treatment initiation and use., Methods: A total of 220 participants, age 18-24 years, who were naive to treatment (except for prevention of mother-to-child HIV transmission; n = 3), completed a comprehensive neurocognitive, substance use, and behavioral health assessment battery., Results: Sixty-seven percent of youth met criteria for HAND (96.4% were asymptomatic and 3.5% were syndromic); deficits in episodic memory and fine-motor skills emerged as the most commonly affected ability areas. Multivariable models showed that lower CD4 count, longer time since HIV diagnosis, and high-risk alcohol use were uniquely associated with neurocognitive deficits., Conclusions: Over two thirds of youth with behaviorally acquired HIV evidence neurocognitive deficits, which have modest associations with more advanced HIV disease as well as other factors. Research is needed to determine the impact of such neuropsychiatric morbidity on mental health and HIV disease treatment outcomes (e.g., nonadherence) and transition to independent living responsibilities in HIV-infected youth, as well as its long-term trajectory and possible responsiveness to cognitive rehabilitation and pharmacotherapy., (Copyright © 2013 Society for Adolescent Health and Medicine. All rights reserved.)

While performance-based tests of everyday functioning offer promise in facilitating diagnosis and classification of HIV-associated neurocognitive disorders (HAND), there remains a dearth of well-validated instruments. In the present study, clinical correlates of performance on one such measure (i.e., Medication Management Test-Revised; MMT-R) were examined in 448 HIV+ adults who were prescribed antiretroviral therapy. Significant bivariate relationships were found between MMT-R scores and demographics (e.g., education), hepatitis C co-infection, estimated premorbid IQ, neuropsychological functioning, and practical work abilities. MMT-R scores were not related to HIV disease severity, psychiatric factors, or self-reported adherence among participants with a broad range of current health status. However, lower MMT-R scores were strongly and uniquely associated with poorer adherence among participants with CD4 T cell counts <200. In multivariate analyses, MMT-R scores were predicted by practical work abilities, estimated premorbid functioning, attention/working memory, learning, and education. Findings provide overall mixed support for the construct validity of the MMT-R and are discussed in the context of their clinical and research implications for evaluation of HAND.

The present study provides supplemental data for the Repeatable Battery for the Assessment of Neuropsychological Status (Randolph, 1998) by reporting base rate data on discrepancies between subtests of this measure. These discrepancies are organized by general level of ability and include both age and education corrections. The data come from the Oklahoma Longitudinal Assessment of Health Outcomes in Mature Adults study and include cognitive performances of 718 community-dwelling older adults. These findings offer the possibility of increased sensitivity at detecting clinically significant differences that might not be identified when relying on base rate data from a greater age range. Similarly, these data highlight the mediating effects of the global level of cognitive functioning on discrepancy scores.

The determination of clinically significant cognitive change across time is an important issue in neuropsychology, and repeated assessments are common with older adults. Regression-based prediction formulas, which use initial test performance and demographic variables to predict follow-up test performance, have been utilized with patient and healthy control samples. Comparisons between predicted and observed follow-up performances can assist clinicians in determining the significance of change in the individual patient. In the current study, multiple regression-based prediction equations for the five Indexes and Total Score of the RBANS were developed for a sample of 146 community-dwelling older adults across a 2-year interval. These algorithms were then validated on a separate elderly sample (n = 145). Minimal differences were present between Observed and Predicted follow-up scores in the validation sample, suggesting that the prediction formulas are clinically useful for practitioners who assess older adults. A case example is presented that illustrates how the algorithms can be used clinically.

Visual construction and memory tasks are routinely used in neuropsychological assessment, but their subjective scoring criteria can negatively affect the reliability of these instruments. The current study examined the standard scoring criteria for the Figure Copy and Recall subtests of the RBANS and compared them to a modified set of scoring criteria in two samples. In both a large community dwelling sample of older adults and in a mixed clinical sample, the original scoring criteria consistently led to lower scores than the modified criteria. Inter-rater reliability was high for the modified scoring criteria, and no age effects were found with the modified scoring criteria. In both samples, the modified scoring criteria led to Figure Copy scores that more closely approximated other performances on the RBANS compared to the standard criteria, whereas both scoring systems led to plausible Figure Recall scores. Despite these results, the present study cannot identify one scoring criterion as the "better," but only points out the significant differences between them. Such differences can have important clinical implications, and practitioners and researchers who utilize the RBANS with patient samples should be cautious when interpreting low scores on Figure Copy and Recall if the standard criteria are used.

The article offers insights on the peer-review process as it relates to scientific and technical reports used to inform regulatory decisions. Used effectively, peer review is a powerful tool for advising organizational leaders whether the scientific foundations of their decisions can be expected to withstand scrutiny as rule-making products move through interagency reviews, public comment and stakeholder processes, congressional oversight, and judicial review. The emphasis is "heads up" rather than "how to." That is, without delving into myriad technical and administrative details, the discussion highlights nine fundamental "leadership responsibilities" that determine the nature and course of peer review.

The present study expands upon the data available in the manual of the Repeatable Battery for the Assessment of Neuropsychological Status, by providing base rate data on Index discrepancies that are organized by general level of ability and include both age and education corrections. The data presented are based on the performances of a sample of 718 community dwelling older adults. These findings offer the possibility of increased sensitivity at detecting clinically significant differences that might not be identified when relying on base rate data from a greater age range. Similarly, these data highlight the mediating effects of the global level of cognitive functioning on discrepancy scores.

A complete mode of action human relevance analysis--as distinct from mode of action (MOA) analysis alone--depends on robust information on the animal MOA, as well as systematic comparison of the animal data with corresponding information from humans. In November 2003, the International Life Sciences Institute's Risk Science Institute (ILSI RSI) published a 2-year study using animal and human MOA information to generate a four-part Human Relevance Framework (HRF) for systematic and transparent analysis of MOA data and information. Based mainly on non-DNA-reactive carcinogens, the HRF features a "concordance" analysis of MOA information from both animal and human sources, with a focus on determining the appropriate role for each MOA data set in human risk assessment. With MOA information increasingly available for risk assessment purposes, this article illustrates the further applicability of the HRF for reproductive, developmental, neurologic, and renal endpoints, as well as cancer. Based on qualitative and quantitative MOA considerations, the MOA/human relevance analysis also contributes to identifying data needs and issues essential for the dose-response and exposure assessment steps in the overall risk assessment.

Vesicular monoamine transporters (VMATs) mediate the transport of dopamine (DA), serotonin (5HT), and other monoamines into secretory vesicles. The regulation of mammalian VMAT and the related vesicular acetylcholine transporter (VAChT) has been proposed to involve membrane trafficking, but the mechanisms remain unclear. To facilitate a genetic analysis of vesicular transporter function and regulation, we have cloned the Drosophila homolog of the vesicular monoamine transporter (dVMAT). We identify two mRNA splice variants (DVMAT-A and B) that differ at their C-terminus, the domain responsible for endocytosis of mammalian VMAT and VAChT. DVMAT-A contains trafficking motifs conserved in mammals but not C. elegans, and internalization assays indicate that the DVMAT-A C-terminus is involved in endocytosis. DVMAT-B contains a divergent C-terminal domain and is less efficiently internalized from the cell surface. Using in vitro transport assays, we show that DVMAT-A recognizes DA, 5HT, octopamine, tyramine, and histamine as substrates, and similar to mammalian VMAT homologs, is inhibited by the drug reserpine and the environmental toxins 2,2,4,5,6-pentachlorobiphenyl and heptachlor. We have developed a specific antiserum to DVMAT-A, and find that it localizes to dopaminergic and serotonergic neurons as well as octopaminergic, type II terminals at the neuromuscular junction. Surprisingly, DVMAT-A is co-expressed at type II terminals with the Drosophila vesicular glutamate transporter. Our data suggest that DVMAT-A functions as a vesicular transporter for DA, 5HT, and octopamine in vivo, and will provide a powerful invertebrate model for the study of transporter trafficking and regulation.

Repeated neuropsychological assessments are common with older adults, and the determination of true neurocognitive change is important for diagnostic assessment. Several statistical formulas are available to assist in this determination, but they rely on access to test-retest stability coefficients and practice effect values. The current study presents data on these psychometric properties of the RBANS in a large community dwelling elderly sample. Across a one-year retest interval, stability coefficients ranged from .58 to .83 for the Index scores, and from .51 to .83 for the subtest scores. Practice effects were largely absent, with most performances slightly decreasing at retest. These psychometric properties are contrasted with those reported in the RBANS manual, and possible reasons for these differences are discussed. A case example is provided that demonstrates the use of the current findings in conjunction with existing change formulas.

Identification of clinically significant change in performance over time on neurocognitive tests is an important aspect of neuropsychological evaluation; however, scant published empirical data exists to guide the clinician in determining the significance of psychometric change across clinically relevant retest intervals. The present study presents base rate data of RBANS score discrepancies in a user-friendly manner based on the performances of a large sample (n=283) of community-dwelling older adults. Data for 1- and 2-year retest intervals are presented in a tabular form that can be used as a convenient reference. Base rates of discrepancy scores were calculated and organized into three groups (i.e., below average, average, and above average) with respect to the participants' OKLAHOMA age- and education-corrected RBANS Total Scale score (Duff, Patton, Schoenberg, Mold, Scott, & Adams, 2003) at initial assessment, in an effort to reduce the influence of regression to the mean and practice effects that is associated with varying levels of cognitive ability. (e.g., Rapport, Axelrod, Theisen, Brines, Kalechstein, & Ricker, 1997; Rapport, Brines, Axelrod, & Theisen, 1997). These data may be helpful in clinical practice by assisting the clinician in determining the clinical significance of score changes.

Recent research suggests that cognitively normal African Americans are more likely to be misdiagnosed as impaired compared to Caucasians due to lower neuropsychological test scores (e.g., Manly et al., 1998). Given this, the present study sought to determine whether such racial discrepancies exist on the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Performances of 50 cognitively normal older African Americans on the RBANS were compared to those of 50 Caucasians matched on age, education, and gender. The African Americans scored significantly lower on 10 of 12 subtests, 3 of 5 Index scores, and the Total Scale score. Results underscored the utility of demographically appropriate norms when serving minority clients. Given that there remains a paucity of normative data for minority groups, RBANS normative data for older African Americans are provided. Although preliminary, it is hoped that data presented will offer the practitioner assistance with clinical diagnosis and decision-making in a manner that will help minimize diagnostic errors.

Risk assessment policies and practice place increasing reliance on mode of action (MOA) data to inform conclusions about the human relevance of animal tumors. In June 2001, the Risk Science Institute of the International Life Sciences Institute formed a workgroup to study this issue. The workgroup divided into two subgroups, one developing and testing a "framework" for MOA relevance analysis and the other conducting an in-depth analysis of peroxisome proliferation-activated receptor (PPAR)alpha activation as the MOA for some animal carcinogens. This special issue of Critical Reviews in Toxicology presents the scientific reports emerging from this activity. These reports serve several purposes. For risk assessors in and out of government, they offer a new human relevance framework (HRF) that complements and extends existing guidance from other organizations. Regarding the specific MOA for peroxisome proliferating chemicals, these reports offer a state-of-the-science review of this important MOA and its role in tumorigenesis in three different tissues (liver, testis, and pancreas). The case studies in these reports present models for using MOA information to evaluate the hazard potential for humans. The cases also illustrate the substantial impact of a complete human relevance analysis, as distinct from an animal MOA analysis alone, on the nature and scope of risk assessment.

The human relevance framework (HRF) outlines a four-part process, beginning with data on the mode of action (MOA) in laboratory animals, for evaluating the human relevance of animal tumors. Drawing on U.S. EPA and IPCS proposals for animal MOA analysis, the HRF expands those analyses to include a systematic evaluation of comparability, or lack of comparability, between the postulated animal MOA and related information from human data sources. The HRF evolved through a series of case studies representing several different MOAs. HRF analyses produced divergent outcomes, some leading to complete risk assessment and others discontinuing the process, according to the data available from animal and human sources. Two case examples call for complete risk assessments. One is the default: When data are insufficient to confidently postulate a MOA for test animals, the animal tumor data are presumed to be relevant for risk assessment and a complete risk assessment is necessary. The other is the product of a data-based finding that the animal MOA is relevant to humans. For the specific MOA and endpoint combinations studied for this article, full risk assessments are necessary for potentially relevant MOAs involving cytotoxicity and cell proliferation in animals and humans (Case Study 6, chloroform) and formation of urinary-tract calculi (Case Study 7, melamine). In other circumstances, when data-based findings for the chemical and endpoint combination studied indicate that the tumor-related animal MOA is unlikely to have a human counterpart, there is little reason to continue the risk assessment for that combination. Similarly, when qualitative considerations identify MOAs specific to the test species or quantitative considerations indicate that the animal MOA is unlikely to occur in humans, such hazard findings are generally conclusive and further risk assessment is not necessary for the endpoint-MOA combination under study. Case examples include a tumor-related protein specific to test animals (Case Study 3, d-limonene), the tumor consequences of hormone suppression typical of laboratory animals but not humans (Case Study 4, atrazine), and chemical-related enhanced hormone clearance rates in animals relative to humans (Case Study 5, phenobarbital). The human relevance analysis is highly specific for the chemical-MOA-tissue-endpoint combination under analysis in any particular case: different tissues, different endpoints, or alternative MOAs for a given chemical may result in different human relevance findings. By providing a systematic approach to using MOA data, the HRF offers a new tool for the scientific community's overall effort to enhance the predictive power, reliability and transparency of cancer risk assessment.

We have cloned a Kv2 potassium channel from squid optic lobe termed sqKv2. Multiple overlapping sqKv2 cDNA clones differed from one another at specific positions by purine transitions. To test whether the purine transitions were generated by RNA editing, we compared a 360 nucleotide genomic sequence with corresponding cDNA sequences (encoding S4-S6) isolated from individual animals and lying on a single gene and exon. cDNA sequences differed from genomic sequence at 17 positions, resulting in 28 unique sequences. There was invariantly an adenosine in the genomic sequence and a guanosine in the edited cDNA sequences. Two of the edits altered the rates of channel closure and slow inactivation. These results extend selective RNA editing to invertebrate taxa and represents a novel mechanism for the posttranscriptional modulation of voltage-gated ion channels.

The sodium channel from adult rat brain consists of a high molecular weight alpha subunit associated with low molecular weight subunits termed beta 1 and beta 2. Coexpression of beta 1 accelerates the macroscopic kinetics of inactivation of adult rat brain IIA, embryonic rat brain III, and rat skeletal muscle SkM1 sodium channel alpha subunits. In addition, beta 1 accelerates the kinetics of activation, as observed with a non-inactivating rat brain IIA mutant. Analysis of the effects of beta 1 on the slowly inactivating brain III alpha subunit shows that both of these effects may be the result of changes in the modal gating behavior of the sodium channels expressed in Xenopus oocytes. Although the adult rat brain beta 1 subunit modulates the functional properties of rat skeletal muscle and embryonic brain III sodium channel alpha subunits, mRNA hybridizing to a beta 1 subunit cDNA probe was only faintly detected in RNA from adult skeletal muscle and not at all in RNA from embryonic brains. These results indicate that the adult rat brain beta 1 subunit can modify the modal gating properties of sodium channel alpha subunits with which it is not normally associated, suggesting the presence of conserved domains for interactions between the different alpha and beta 1 subunits of the sodium channel.

The short cytoplasmic peptide segment connecting domains III and IV of voltage-gated sodium channels (III-IV linker) is essential for fast inactivation. To test the functional similarity between the III-IV linker and the potassium channel inactivation particle, we attached the III-IV linker to the amino terminus of a noninactivating potassium channel. This chimeric channel inactivated rapidly and displayed biophysical properties similar to Shaker A-type potassium channels. Recovery from inactivation in the chimeric channels was accelerated by high external potassium, consistent with the idea that potassium ions passing through the channel displaced the III-IV linker inactivation particle. A mutation that completely abolishes fast inactivation in rat brain sodium channels also completely abolished inactivation in the chimera. These results demonstrate that the sodium channel III-IV linker can function as a fast inactivation gate and suggest a functional relationship between the fast inactivation processes of sodium and potassium channels.

The inward Na+ current underlying the action potential in nerve is terminated by inactivation. The preceding report shows that deletions within the intracellular linker between domains III and IV remove inactivation, but mutation of conserved basic and paired acidic amino acids has little effect. Here we show that substitution of glutamine for three clustered hydrophobic amino acids, Ile-1488, Phe-1489, and Met-1490, completely removes fast inactivation. Substitution of Met-1490 alone slows inactivation significantly, substitution of Ile-1488 alone both slows inactivation and makes it incomplete, and substitution of Phe-1489 alone removes inactivation nearly completely. These results demonstrate an essential role of Phe-1489 in Na(+)-channel inactivation. It is proposed that the hydrophobic cluster of Ile-1488, Phe-1489, and Met-1490 serves as a hydrophobic latch that stabilizes the inactivated state in a hinged-lid mechanism of Na(+)-channel inactivation.

The cytoplasmic linker connecting domains III and IV of the voltage-gated Na+ channel is thought to be involved in fast inactivation. This linker is highly conserved among the various Na+ channels that have been cloned. In the rat brain IIA Na+ channel, it consists of 53 amino acids of which 15 are charged. To investigate the role of this linker in inactivation, we mutated all 15 of the charged residues in various combinations. All but one of these mutants expressed functional channels, and all of these inactivated with kinetics similar to the wild-type channel. We then constructed a series of deletion mutations that span the III-IV linker to determine if any region of the linker is essential for fast inactivation. Deletion of the first 10 amino acids completely eliminated fast inactivation in the channel, whereas deletion of the last 10 amino acids had no substantial effect on inactivation. These results demonstrate that some residues in the amino end of the III-IV linker are critical for fast Na(+)-channel inactivation, but that the highly conserved positively charged and paired negatively charged residues are not essential.

Voltage-sensitive sodium channels are responsible for the initiation and propagation of the action potential and therefore are important for neuronal excitability. Complementary DNA clones encoding the beta 1 subunit of the rat brain sodium channel were isolated by a combination of polymerase chain reaction and library screening techniques. The deduced primary structure indicates that the beta 1 subunit is a 22,851-dalton protein that contains a single putative transmembrane domain and four potential extracellular N-linked glycosylation sites, consistent with biochemical data. Northern blot analysis reveals a 1,400-nucleotide messenger RNA in rat brain, heart, skeletal muscle, and spinal cord. Coexpression of beta 1 subunits with alpha subunits increases the size of the peak sodium current, accelerates its inactivation, and shifts the voltage dependence of inactivation to more negative membrane potentials. These results indicate that the beta 1 subunit is crucial in the assembly, expression, and functional modulation of the heterotrimeric complex of the rat brain sodium channel.

We have utilized molecular biological techniques to demonstrate that rat IIA sodium channels expressed in Xenopus oocytes were blocked by tetrodotoxin (TTX) in a use-dependent manner. This use dependence was the result of an increased affinity of the channels for TTX upon depolarization, most likely due to a conformational change in the channel. Using a mutant with a slower macroscopic rate of inactivation, we have demonstrated that this conformational change is not the transition into the fast-inactivated state. The transition is probably one occurring during activation of the channel, as suggested by the fact that one sodium channel mutant demonstrated comparable depolarizing shifts in the voltage dependence of both activation and use-dependent block by TTX. The transition occurred at potentials more negative than those resulting in channel conductance, suggesting that the conformational change that causes use-dependent block by TTX is a closed-state voltage-dependent gating transition.

Intrapartum fetal scalp sampling for platelet counts in maternal autoimmune thrombocytopenia has been advocated for determining route of delivery. We report a case in which two coagulated scalp samples were believed to indicate a normal fetal platelet count. As a result, vaginal delivery of a severely thrombocytopenic fetus was allowed.

Pulsed Doppler and M-mode maternal echocardiography were combined with uterine and umbilical artery Doppler velocimetry to characterize the hemodynamic changes associated with fluid preload and epidural anesthesia in 12 normal laboring gravidas at term. Fluid preload alone was associated with significant (P less than .05) increases in heart rate (11%), stroke volume (10%), and cardiac output (20%), and a decrease in systemic vascular resistance (19%). There were no changes in mean arterial pressure (MAP) or ejection fraction during any stage of the study. Following placement of the epidural block, stroke volume and cardiac output returned to values not significantly different from baseline, whereas heart rate remained elevated and systemic vascular resistance remained decreased. There were no changes in uterine or umbilical artery systolic-diastolic (S-D) ratios during any stage of the study. We conclude that fluid preload and epidural anesthesia cause significant changes in maternal cardiac output, heart rate, stroke volume, and systemic vascular resistance without affecting MAP. These maternal changes do not correlate with any changes in uterine or umbilical artery S-D ratios following epidural anesthesia in the normal laboring gravida.

Cyanotic heart disease has major implications for maternal and fetal well-being during pregnancy. This article reports six patients with cyanotic congenital heart disease recently managed at our institutions. Although the maternal condition deteriorated to some extent during each pregnancy, it was the fetal condition that ultimately dictated delivery in each case.

The United States Environmental Protection Agency administers several laws and programs through which it reviews the hazard potential of pesticides and other toxic substances which may present a risk to human health or the environment. The Agency's ability to assess hazard as required by law depends in part on test data developed through testing standards in Agency regulations. In reviewing the Agency's actions in this regard, the courts emphasize the importance of reasoned regulatory decisions. The legal requirements to assess risk and provide and provide reasoned decisions in this regard establish the legal importance of testing guidelines and test data, and indicate that sound test methodology is as important legally as it is scientifically.

Intravenous pancuronium bromide was administered into the umbilical cord by funipuncture to effect temporary fetal paralysis. Neuromuscular blockade was achieved in 12 fetuses undergoing a total of 34 intrauterine procedures for the treatment of severe red-cell alloimmunization. The same initial dose of 0.2 mg/kg fetal weight estimated by ultrasound was used in all cases, but anemic fetuses did not resume movement for prolonged periods. A relationship among fetal hematocrit, adjusted dose, and duration of paralysis was described by the equation: Duration (hours) = 5.24 + 10.30 adjusted dose (mg/kg) - 0.16 hematocrit (%) (R2 = 0.49; P less than .001). Intravenous pancuronium was found to be a safe and effective method for cessation of fetal movement during intrauterine procedures.

Three synthetic oligodeoxynucleotides complementary to different parts of an RNA encoding a glycine receptor subunit were used to discriminate heterogenous mRNAs coding for glycine receptors in adult and neonatal rat spinal cord. Injection of the three antisense oligonucleotides into Xenopus oocytes specifically inhibited the expression of glycine receptors by adult spinal cord mRNA. In contrast, the antisense oligonucleotides were much less potent in inhibiting the expression of glycine receptors encoded by neonatal spinal cord mRNA. Northern blot analysis revealed that the oligonucleotides hybridized mostly to an adult cord transcript of approximately 10 kilobases in size. This band was also present in neonatal spinal cord mRNA but its density was about one-fourth of the adult cord message. There was no intense band in the low molecular weight position (approximately 2 kilobases), the existence of which was expected from electrophysiological studies with size-fractionated mRNA of neonatal spinal cord. Our results suggest that in the rat spinal cord there are at least three different types of mRNAs encoding functional strychnine-sensitive glycine receptors.