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There are described results of researches regarding application of the new means for control of mode of electric power transmission and distribution on the basis of IPC (Interphase Power Controller) taking into account development of external connections of the Moldavian power supply system. The variant of application of classical IPC on base of High Voltage Line Beltsy-Suceava is considered. The management method by power flows in this section on the basis of application of PST (Phase Shift transformer), connected in parallel with IPC is offered and investigated and its technical efficiency is proved.

Introduction Botulinum toxins have proven efficacy and safety for treating cervical dystonia. The consistency of clinical benefit among patients, however, is affected by various factors, including the stability of the toxin formulation. The present study investigates the stability of NeuroBloc™, a liquid formulation of the B serotype, at 2-8 °C and, importantly, at room temperature (25 °C) in the longer term. Methods The mouse intraperitoneal LDs0 potency assay was used to measure NeuroBloC stability. The test sample was prepared in a dilution series based on target potency. Eight mice were used per dilution, five dilutions (levels) per test, and five tests per assay. Mice were observed daily for 4 days postinjection. Results There was no significant change in product potency under either storage condition. Storage at 2-8 °C: mean potency after 12 months was 103% of target (range 92-111%; nine lots), and after 30 months was 92% of target (range 86-98%; three lots). Storage at 25 °C: after 6 months, mean potency was 100% of target (range 82-114%; nine lots). All these final results are within acceptable product-release specifications. Conclusions NeuroBloC retains potency for at least 30 months when refrigerated (2-8 °C) and for at least 6 months at room temperature (25 °C). The extraordinary stability of the liquid formulation of NeuroBloC may contribute to improved consistency in clinical outcomes. [ABSTRACT FROM AUTHOR]

Having a disability, in particular, an intellectual disability, is associated with Internet non-use. This article explores how people with intellectual disabilities used the Internet across the United Kingdom during the COVID-19 pandemic. In April to May 2021, 571 adults with intellectual disabilities were interviewed. Participants most commonly used the Internet for being with family and friends, social media or doing online activities with other people. People who lived with family were the most likely to use social media; people who lived with other people with intellectual disabilities were the least likely. People who self-reported as not lonely were more likely to use the Internet for online activities with others and play video games with others. Social connections were identified as the best thing about the Internet. Many participants chose not to identify a worst thing about Internet use, while others reported issues with technology, online harm and threats to well-being., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article., (© The Author(s) 2022.)

Background: One in five children with an intellectual disability in the UK display behaviours that challenge. Despite associated impacts on the children themselves, their families, and services, little research has been published about how best to design, organise, and deliver health and care services to these children. The purpose of this study was to describe how services are structured and organised ("service models") in England for community-based health and care services for children with intellectual disability who display behaviours that challenge., Methods: Survey data about services were collected from 161 eligible community-based services in England. Staff from 60 of these services were also interviewed. A combination of latent class and descriptive analysis, coupled with consultation with family carers and professionals was used to identify and describe groupings of similar services (i.e., "service models")., Results: The latent class analysis, completed as a first step in the process, supported a distinction between specialist services and non-specialist services for children who display behaviours that challenge. Planned descriptive analyses incorporating additional study variables were undertaken to further refine the service models. Five service models were identified: Child and Adolescent Mental Health Services (CAMHS) (n = 69 services), Intellectual Disability CAMHS (n = 28 services), Children and Young People Disability services (n = 25 services), Specialist services for children who display behaviours that challenge (n = 27 services), and broader age range services for children and/or adolescents and adults (n= 12 services)., Conclusions: Our analysis led to a typology of five service models for community health and care services for children with intellectual disabilities and behaviours that challenge in England. Identification of a typology of service models is a first step in building evidence about the best provision of services for children with intellectual disabilities who display behaviours that challenge. The methods used in the current study may be useful in research developing service typologies in other specialist fields of health and care., Study Registration: Trial Registration: Current Controlled Trials ISRCTN88920546, Date assigned 05/07/2022., (© 2023. The Author(s).)

Background: Most parents of children with an intellectual disability or who are autistic identify positives in their family life and their own wellbeing, in addition to reported mental health challenges. Several models and interventions have been developed in relation to parent carer wellbeing. Few studies have asked parent carers how they support their own wellbeing., Method: Adopting an interpretive phenomenological approach this study utilised semi-structured interviews. Seventeen parent carers were asked what supported their emotional wellbeing. Template Analysis was applied to develop themes., Results: All participants identified factors that supported their wellbeing. Themes included strategies that countered stress (time for themselves, relaxation, 'parking' difficulties) and broader wellbeing strategies (finding meaningful life direction, greater understanding of child). An ongoing process of supporting wellbeing by 'Reorienting and Finding Balance' appeared central., Conclusions: Self-identified, multi-dimensional strategies benefit parents' emotional wellbeing and should be considered in the context of support provided to families., (© 2023 The Authors. Journal of Applied Research in Intellectual Disabilities published by John Wiley & Sons Ltd.)

The present study develops a comprehensive traffic conflict assessment framework using macroscopic traffic state variables. To this end, vehicular trajectories extracted for a midblock section of a ten-lane divided Western Urban Expressway in India are used. A macroscopic indicator termed "time spent in conflict (TSC)" is adopted to evaluate traffic conflicts. The proportion of Stopping distance (PSD) is adopted as a suitable traffic conflict indicator. Vehicle-to-vehicle interactions in a traffic stream are two-dimensional, highlighting that the vehicles interact simultaneously in lateral and longitudinal dimensions. Therefore, a two-dimensional framework based on the influence zone of the subject vehicle is proposed and employed to evaluate TSCs. The TSCs are modeled as a function of macroscopic traffic flow variables, namely, traffic density, speed, the standard deviation in speed, and traffic composition, under a two-step modeling framework. In the first step, the TSCs are modeled using a grouped random parameter Tobit (GRP-Tobit) model. In the second step, data-driven machine learning models are employed to model TSCs. The results revealed that intermediately congested traffic flow conditions are critical for traffic safety. Furthermore, macroscopic traffic variables positively influence the value of TSC, highlighting that the TSC increases with an increase in the value of any independent variable. Among different machine learning models, the random forest (RF) model was observed as the best-fitted model to predict TSC based on macroscopic traffic variables. The developed machine learning model facilitates traffic safety monitoring in real-time., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Un-signalized intersections in India witnessed the maximum number of crashes and fatalities in 2019. The nature of the crash investigation is still largely reactive, where the need for accurate and reliable crash data for effective safety diagnosis is pivotal. In India, crash records are unscientific, and critical details are missing. Therefore, a proactive approach using surrogate safety measures is more promising and prudent in analyzing traffic safety. The present study investigates and models crossing conflicts at un-signalized intersections under mixed traffic conditions. Traffic video data for 14 un-signalized intersections (eight un-signalized three-legged intersections and six un-signalized four-legged intersections) were collected under normal weather conditions. The crossing conflicts were identified and characterized as critical and noncritical conflicts based on the values of post-encroachment time (PET). Conflicts with PET values between -1 s and 1 s were identified as critical conflicts. The observation revealed the existence of both positive and negative PET values. The investigation revealed that crossing conflicts with negative PET values are riskier and more unsafe than conflicts with positive ones. Therefore, the crossing conflicts with positive and negative PETs were modeled separately. The positive and negative PET-based critical crossing conflicts are modeled as a function of traffic flow and intersection geometry-related characteristics using truncated negative binomial regression under a full Bayesian modeling framework. K-fold cross-validation with fivefold was employed to calibrate the model, and RMSE was used to find the best model. The modeling results revealed that the volume and traffic composition of the offending and conflicting stream and intersection geometry significantly influence the number of positive and negative PET-based critical crossing conflicts. The developed models can interest engineers and safety experts to analyze traffic safety and identify critical intersections in urban road networks.

Introduction: Demand for donor kidneys far exceeds the availability of organs from deceased donors. Living donor kidneys are an important part of addressing this shortfall, and laparoscopic nephrectomy is an important strategy to reduce donor morbidity and increase the acceptability of living donation., Aim: To retrospectively review the intraoperative and postoperative safety, technique, and outcomes of patients undergoing donor nephrectomy at a single tertiary hospital in Sydney, Australia., Method: Retrospective capture and analysis of clinical, demographic, and operative data for all living donor nephrectomies performed between 2007 and 2022 at a single University Hospital in Sydney, Australia., Results: Four hundred and seventy-two donor nephrectomies were performed: 471 were laparoscopic, two of which were converted from laparoscopic to open and hand-assisted nephrectomy, respectively, and one (.2%) underwent primary open nephrectomy. The mean warm ischemia time was 2.8 min (±1.3 SD, median 3 min, range 2-8 min) and the mean length of stay (LOS) was 4.1 days (±1.0 SD). The mean renal function on discharge was 103 μmol/L (±23.0 SD). Seventy-seven (16%) patients had a complication with no Clavien Dindo IV or V complications seen. Outcomes demonstrated no impact of donor age, gender, kidney side, relationship to the recipient, vascular complexity; or surgeon experience, on complication rate or LOS., Conclusion: Laparoscopic donor nephrectomy is a safe and effective procedure with minimal morbidity and no mortality in this series., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Early Positive Approaches to Support (E-PAtS) is a co-produced and co-facilitated group programme that aims to provide early years support to family caregivers of children with Intellectual and Developmental Disabilities., Method: Thirty-five caregivers who had attended E-PAtS groups took part in individual interviews or focus groups. Caregiver experiences concerning attendance of E-PAtS were explored, in relation to process variables and perceived outcomes. Interviews were thematically analysed., Results: Three major themes were identified: our group, evolving emotions, and positive approaches. Being with and being supported by other families was very important to caregivers. Families reported increased confidence and greater realisation of the need for self-care. Children were reported to show fewer behaviours that challenge and increases in adaptive skills. Findings corresponded to mechanisms and outcomes in the E-PAtS logic model., Conclusion: E-PAtS shows promise as one way families and children with Intellectual and Developmental Disabilities can access early years support., (© 2022 The Authors. Journal of Applied Research in Intellectual Disabilities published by John Wiley & Sons Ltd.)

Background: Children with intellectual disability have an IQ < 70, associated deficits in adaptive skills and are at increased risk of having clinically concerning levels of behaviour problems. In addition, parents of children with intellectual disability are likely to report high levels of mental health and other psychological problems. The Early Positive Approaches to Support (E-PAtS) programme for family caregivers of young children (5 years and under) with intellectual and developmental disabilities is a group-based intervention which aims to enhance parental psychosocial wellbeing and service access and support positive development for children. The aim of this study is to assess the feasibility of delivering E-PAtS to family caregivers of children with intellectual disability by community parenting support service provider organisations. The study will inform a potential, definitive RCT of the effectiveness and cost-effectiveness of E-PAtS., Methods: This study is a feasibility cluster randomised controlled trial, with embedded process evaluation. Up to 2 family caregivers will be recruited from 64 families with a child (18 months to 5 years) with intellectual disability at research sites in the UK. Participating families will be allocated to intervention: control on a 1:1 basis; intervention families will be offered the E-PAtS programme immediately, continuing to receive usual practice, and control participants will be offered the opportunity to attend the E-PAtS programme at the end of the follow-up period and will continue to receive usual practice. Data will be collected at baseline, 3 months post-randomisation and 12 months post-randomisation. The primary aim is to assess feasibility via the assessment of: recruitment of service provider organisations; participant recruitment; randomisation; retention; intervention adherence; intervention fidelity and the views of participants, intervention facilitators and service provider organisations regarding intervention delivery and study processes. The secondary aim is preliminary evaluation of a range of established outcome measures for individual family members, subsystem relationships and overall family functioning, plus additional health economic outcomes for inclusion in a future definitive trial., Discussion: The results of this study will inform a potential future definitive trial, to evaluate the effectiveness and cost-effectiveness of the E-PAtS intervention to improve parental psychosocial wellbeing. Such a trial would have significant scientific impact internationally in the intellectual disability field., Trial Registration: ISRCTN70419473., Competing Interests: Competing interestsNick Gore is a programme developer for the E-PAtS intervention. All remaining authors declare that they have no competing interests., (© The Author(s) 2020.)

Very little is known of the activities of the most senior managers in organisations providing social care in the community to people with intellectual disabilities. Yet the importance of the focus and activities of senior managers in directing and supporting staff practice and staff experiences is likely to be central to an organisation's functioning and support provided for staff and service users. This study employed Delphi methodology with a panel of 11 senior managers, mostly chief executives, managing small to very large organisations providing support for people with intellectual disabilities, in the UK. Answering three rounds of questions, senior managers described their face-to-face and non-face-to-face contacts with staff and decision-making. Narrative data were subject to quantitative and thematic analysis. In the last round, themes were subject to quantitative analysis. Most contacts between senior managers and staff were in formal structured contexts and all managers used social media to promote the organisations' ambitions regarding good practice. The panel focused upon accessing and understanding the informal aspects of their organisations and staff factors. Decisions were both short-term reactive and long-term strategic and an effort to link these was felt to improve organisational functioning. A framework for understanding senior managers' activities emerged showing two sources of demands and opportunity, extra-organisational focused upon meeting legal and regulatory demands and intra-organisational focused upon understanding and influencing informal staff practices/experiences and cultures within their organisations., (© 2019 John Wiley & Sons Ltd.)

Objective: Mental health problems are more prevalent in people with than without intellectual disabilities, yet treatment options have received little attention. The aim of this study was to identify and evaluate the effectiveness of pharmacological and psychological interventions in the treatment of mental health problems in children and adults with severe and profound intellectual disabilities, given their difficulties in accessing standard mental health interventions, particularly talking therapies, and difficulties reporting drug side effects., Design: A systematic review using electronic searches of PsycINFO, PsycTESTS, EMBASE, MEDLINE, CINAHL, ERIC, ASSIA, Science Citation Index, Social Science Citation Index and CENTRAL was conducted to identify eligible intervention studies. Study selection, data extraction and quality appraisal were performed by two independent reviewers., Participants: Study samples included at least 70% children and/or adults with severe or profound intellectual disabilities or reported the outcomes of this subpopulation separate from participants with other levels of intellectual disabilities., Interventions: Eligible intervention studies evaluated a psychological or pharmacological intervention using a control condition or pre-post design., Outcomes: Symptom severity, frequency or other quantitative dimension (e.g., impact), as assessed with standardised measures of mental health problems., Results: We retrieved 41 232 records, reviewed 573 full-text articles and identified five studies eligible for inclusion: three studies evaluating pharmacological interventions, and two studies evaluating psychological interventions. Study designs ranged from double-blind placebo controlled crossover trials to single-case experimental reversal designs. Quality appraisals of this very limited literature base revealed good experimental control, poor reporting standards and a lack of follow-up data., Conclusions: Mental ill health requires vigorous treatment, yet the current evidence base is too limited to identify with precision effective treatments specifically for children or adults with severe and profound intellectual disabilities. Clinicians therefore must work on the basis of general population evidence, while researchers work to generate more precise evidence for people with severe and profound intellectual disabilities., Prospero Registration Number: CRD 42015024469., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Introduction: Intra-Gastric Balloon (IGB) is increasingly used as a non-operative management strategy in bariatric patients. However, as IGB use has become more prevalent, new potentially life-threatening adverse effects have emerged. We report a case of IGB-related acute pancreatitis from a tertiary referral hospital. A literature review of electronic databases was conducted to identify other cases PRESENTATION OF CASE: A 20-year-old female presented to the emergency department with acute onset of epigastric pain on day-1 post-insertion of an IGB (Orbera ® ). The diagnosis of acute pancreatitis was made on the basis of the clinical picture, with radiological and serological confirmation. Complete resolution of symptoms promptly followed endoscopic removal of the balloon., Discussion: We examine all prior reported cases of IGB associated pancreatitis in the literature, as well as the impact of the particular balloon subtypes. Mass effect of the device on the pancreas or dislodgement of the rigid catheter into the second part of the duodenum appear to be the underlying cause in all cases. While there were no deaths reported, major sequelae have been noted, including presence of mucosal ischemia and failure to retrieve the balloon endoscopically, necessitating laparotomy., Conclusion: Although the incidence of IGB-induced pancreatitis is still rare, this complication which must be highlighted as a potentially serious adverse outcome., (Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Mental health problems affect people with intellectual disabilities (ID) at rates similar to or in excess of the non-ID population. People with severe ID are likely to have persistent mental health problems. In this systematic review (PROSPERO 2015:CRD42015024469), we identify and evaluate the methodological quality of available measures of mental health problems or well-being in individuals with severe or profound ID. Electronic searches of ten databases identified relevant publications. Two reviewers independently reviewed titles and abstracts of retrieved records (n=41,232) and full-text articles (n=573). Data were extracted and the quality of included papers was appraised. Thirty-two papers reporting on 12 measures were included. Nine measures addressed a broad spectrum of mental health problems, and were largely observational. One physiological measure of well-being was included. The Aberrant Behavior Checklist, Diagnostic Assessment for the Severely Handicapped Scale-II and Mood, Interest and Pleasure Questionnaire are reliable measures in this population. However, the psychometric properties of six other measures were only considered within a single study - indicating a lack of research replication. Few mental health measures are available for people with severe or profound ID, particularly lacking are tools measuring well-being. Assessment methods that do not rely on proxy reports should be explored further., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Pseudomonas aeruginosa opportunistically infects the airways of patients with cystic fibrosis and causes significant morbidity and mortality. Initial infection can often be eradicated though requires prompt detection and adequate treatment. Intermittent and then chronic infection occurs in the majority of patients. Better detection of P. aeruginosa infection using biomarkers may enable more successful eradication before chronic infection is established. In chronic infection P. aeruginosa adapts to avoid immune clearance and resist antibiotics via efflux pumps, β-lactamase expression, reduced porins and switching to a biofilm lifestyle. The optimal treatment strategies for P. aeruginosa infection are still being established, and new antibiotic formulations such as liposomal amikacin, fosfomycin in combination with tobramycin and inhaled levofloxacin are being explored. Novel agents such as the alginate oligosaccharide OligoG, cysteamine, bacteriophage, nitric oxide, garlic oil and gallium may be useful as anti-pseudomonal strategies, and immunotherapy to prevent infection may have a role in the future. New treatments that target the primary defect in cystic fibrosis, recently licensed for use, have been associated with a fall in P. aeruginosa infection prevalence. Understanding the mechanisms for this could add further strategies for treating P. aeruginosa in future., (© FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Pseudomonas aeruginosa is a remarkably versatile environmental bacterium with an extraordinary capacity to infect the cystic fibrosis (CF) lung. Infection with P. aeruginosa occurs early, and although eradication can be achieved following early detection, chronic infection occurs in over 60% of adults with CF. Chronic infection is associated with accelerated disease progression and increased mortality. Extensive research has revealed complex mechanisms by which P. aeruginosa adapts to and persists within the CF airway. Yet knowledge gaps remain, and prevention and treatment strategies are limited by the lack of sensitive detection methods and by a narrow armoury of antibiotics. Further developments in this field are urgently needed in order to improve morbidity and mortality in people with CF. Here, we summarize current knowledge of pathophysiological mechanisms underlying P. aeruginosa infection in CF. Established treatments are discussed, and an overview is offered of novel detection methods and therapeutic strategies in development.

Background: Uncomplicated urinary tract infection (UTI) is the most common bacterial infection in women, characterised by dysuria and urinary frequency. Urinary alkalisers are widely used in some countries for the symptomatic treatment of uncomplicated UTI, and they are recommended in some national formularies. However, there is a lack of empirical evidence to support their use for UTI and some healthcare guidelines advise against their use., Objectives: We aimed to look at the benefits and harms of the use of urinary alkalisers for the treatment of uncomplicated UTIs in adult women., Search Methods: We searched the Cochrane Kidney and Transplant Specialised Register to 19 January 2016 through contact with the Trials Search Co-ordinator using search terms relevant to this review., Selection Criteria: All randomised controlled trials (RCTs) and quasi-RCTs on the use of (any) urinary alkalisers (either exclusively or non-exclusively) for the symptomatic treatment of uncomplicated UTI amongst women aged 16 and over, were included. Studies were eligible if they included patients whose diagnosis of UTI was decided by symptoms alone, or positive urine dipstick test or urine culture; and patients with recurrent UTI, provided patients had no symptoms of UTI in the two weeks prior to the onset of symptoms that lead them to seek medical advice. Studies were ineligible if they studied patients with complicated UTIs; immune-compromising conditions; acute pyelonephritis; or chronic conditions such as interstitial cystitis., Data Collection and Analysis: Three authors independently assessed and screened papers, and this was repeated by two separate authors (independently). An additional investigator acted as arbitrator, where necessary. There were no papers which fulfilled the inclusion criteria for this review, and therefore no data extraction was performed., Main Results: Our search identified 172 potential studies for inclusion. However, following assessment none fulfilled the inclusion criteria for this review., Authors' Conclusions: Until relevant evidence is generated from randomised trials, the safety and efficacy of urinary alkalisers for the symptomatic treatment of uncomplicated UTI remains unknown.

The current study presents findings from an acceptance and commitment therapy-based intervention for family carers of children who have an intellectual/developmental disability and display high levels of challenging behaviour. The parent well-being workshops consist of two workshops incorporating acceptance and mindfulness-based exercises and discussions. Semi-structured interviews were conducted with five family carers following attendance of the workshops. Participants found the workshops useful and reported that they were better able to cope with stress. They also described how they had incorporated mindfulness into their daily lives and how their practice had had positive effects on their own well-being and on those around them (e.g. their child). Implications of the findings are discussed with emphasis on how the workshops can be included within a positive behaviour support framework. Future directions include a more robust quantitative evaluation, inclusion of follow-up sessions and the application of the workshops with other client groups and in other delivery formats., (© The Author(s) 2015.)

Children with intellectual disability are at increased risk of experiencing poor health relative to their typically developing peers. Previous research indicates that exposure to socio-economic disadvantage contributes towards this disparity but that additional factors (including parenting practices) may be involved in mediating/moderating pathways. This study examined duration of breastfeeding amongst children with and without intellectual disability by a secondary analysis of data from the UK Millennium Cohort Study. Children with intellectual disability were significantly less likely to have been ever breastfed; breastfed exclusively or at all at 3 months or breastfed at all at 6 months relative to children without intellectual disability. None of these differences remained significant when other psycho-social risk factors for reduced breastfeeding were controlled for. The study adds to both the sparse literature on breastfeeding practices amongst families of children with intellectual disability and research demonstrating relationships between socio-economic disadvantage and wellbeing for children with intellectual disability., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Research has found staff attitudes regarding the sexuality of people with intellectual disability (ID) to be negative but influenced by several factors. The current study aimed to examine whether gender of people with ID affects such attitudes., Method: Semistructured interviews were completed with 10 staff members and analysed using thematic analysis., Results: Results indicated 3 themes: Women are perceived as sexually innocent, men as more sexually motivated, and motivations for sexual relationships are perceived to differ between men and women with ID., Conclusion: The study indicates unfavourable attitudes towards sexuality in individuals with ID that correlate with traditional, restricted gender stereotypes. The identification of these themes highlights the importance of considering gender when supporting the sexuality of people with ID.

The islet amyloid polypeptide (IAPP) gene is expressed primarily in the islet beta-cell and the peptide is co-secreted with insulin. To investigate mechanisms important in its regulation, we have used the electrophoretic mobility-shift assay and methylation interference to determine systematically sites of DNA-protein interactions in the human IAPP promoter. We identified beta-cell-specific DNA-protein complexes at three sites, each of which contained a consensus binding site for insulin upstream factor I (IUF-I). This complex was displaced with an antiserum to IUF-1, confirming that IUF-1 binds to the human IAPP promoter in vitro. We have also identified a DNA-protein complex within the region -220/-250 in both beta- and non-beta-cell lines. This region contains a motif with partial identity with the binding site for the ubiquitous transcription factor upstream stimulatory factor (USF), which binds to the human insulin promoter. However, purified USF was not able to bind to this putative site in the IAPP promoter and an oligonucleotide containing a functional USF-binding site was unable to displace binding from the IAPP oligonucleotide. Methylation interference revealed that the DNA-protein complex binds to a sequence that overlaps the USE-like sequence, and may therefore be a novel helix-loop-helix protein. These results suggest that, although both IAPP and insulin are beta-cell peptides, IAPP contains regulatory regions both common to and distinct from insulin.

A protocol for establishing standard instrument conditions for measurement of product ion MS/MS spectra from parent ions produced by electron ionization is presented. Within this protocol, the ion at m/z 231 (C5F9 (+)) from perfluorokerosene or perfluorotributylamine is selected as the parent ion and subjected to collision-induced dissociation. The relative intensities of product ions at m/z 69, 131, and 181 are monitored as a function of collision energy while keeping the target gas pressure constant within the range of 10(-4)-10(-6) torr (measured), or a beam attenuation of approximately 30-70%. The collision energy at which the ion intensities for product ions at m/z 69 and 181 are equal is defined as the calibration point at that collision gas pressure; the intensity of the ion at m/z 131 is very close to this value as well. Electron ionization MS/MS spectra taken at the calibration point using two different multiquadrupole instruments show good reproducibility for several test compounds. The high degree of similarity may aid in the establishment of a MS/MS spectral library.

Leucine:tRNA ligase was assayed in extracts from cultured tobacco (Nicotiana tabacum) XD cells by measuring the initial rate of aminoacylation of transfer RNA with l-[4,5-(3)H]leucine. Transfer RNA was purified from tobacco XD cells after the method of Vanderhoef et al. (Phytochemistry 9: 2291-2304). The buoyant density of leucine:tRNA ligase from cells grown for 100 generations in 2.5 mm [(15)N]nitrate and 30% deuterium oxide was 1.3397. After transfer of cells into light medium (2.5 mm [(14)N]nitrate and 100% H(2)O) the ligase activity increased and the buoyant density decreased with time to 1.3174 at 72 hours after transfer. It was concluded that leucine:tRNA ligase molecules were synthesized de novo from light amino acids during the period of activity increase. The width at half-peak height of the enzyme distribution profiles following isopycnic equilibrium centrifugation in caesium chloride remained constant at all times after transfer into light medium providing evidence for the loss of preexisting functional ligase molecules. It was concluded that during the period of activity increase the cellular level of enzyme activity was determined by a balance between de novo synthesis and the loss of functional enzyme molecules due to either inactivation or degradation.