DNA Polymerase Epsilon Deficiency Causes IMAGe Syndrome with Variable Immunodeficiency.

During genome replication, polymerase epsilon (Pol ε) acts as the major leading-strand DNA polymerase. Here we report the identification of biallelic mutations in POLE, encoding the Pol ε catalytic subunit POLE1, in 15 individuals from 12 families. Phenotypically, these individuals had clinical features closely resembling IMAGe syndrome (intrauterine growth restriction [IUGR], metaphyseal dysplasia, adrenal hypoplasia congenita, and genitourinary anomalies in males), a disorder previously associated with gain-of-function mutations in CDKN1C. POLE1-deficient individuals also exhibited distinctive facial features and variable immune dysfunction with evidence of lymphocyte deficiency. All subjects shared the same intronic variant (c.1686+32C>G) as part of a common haplotype, in combination with different loss-of-function variants in trans. The intronic variant alters splicing, and together the biallelic mutations lead to cellular deficiency of Pol ε and delayed S-phase progression. In summary, we establish POLE as a second gene in which mutations cause IMAGe syndrome. These findings add to a growing list of disorders due to mutations in DNA replication genes that manifest growth restriction alongside adrenal dysfunction and/or immunodeficiency, consolidating these as replisome phenotypes and highlighting a need for future studies to understand the tissue-specific development roles of the encoded proteins.

Development of an interactive model for planning the care workforce for Alberta: case study.

INTRODUCTION: In common with other jurisdictions, Alberta faces challenges in ensuring a balance in health worker supply and demand. As the provider organization with province-wide responsibility, Alberta Health Services needed to develop a forecasting tool to inform its position on key workforce parameters, in the first instance focused on modeling the situation for Registered Nurses, Licensed Practical Nurses and health care aides. This case study describes the development of the model, highlighting the choices involved in model development. CASE DESCRIPTION: A workforce planning model was developed to test the effect of different assumptions (for instance about vacancy rates or retirement) and different policy choices (for example about the size of intakes into universities and colleges, different composition of the workforce). This case study describes the choices involved in designing the model. The workforce planning model was used as part of a consultation process and to develop six scenarios (based on different policy choices). DISCUSSION AND EVALUATION: The model outputs highlighted the problems with continuation of current workforce strategies and the impact of key policy choices on workforce parameters. CONCLUSIONS: Models which allow for transparency of the underlying assumptions, and the ability to assess the sensitivity of assumptions and the impact of policy choices are required for effective workforce planning.

Planning to meet the care need challenge in Alberta, Canada.

The Canadian province of Alberta faces challenges in ensuring an adequate supply of nurses to meet care needs. This paper describes the approach adopted by Alberta Health Services (the public health care provider in Alberta) to address this challenge. Planning was undertaken on the basis of care needs rather than starting from a particular professional perspective and highlighted that the needs could be met by Registered Nurses, Licensed Practical Nurses or Healthcare Aides. Six scenarios, representing different potential mixes of Registered Nurses, Licensed Practical Nurses and Healthcare Aides were identified and used as the basis of stakeholder consultations. The paper identifies the workforce outcomes and needs for the different scenarios and the outcomes of the workforce planning process.

Antidepressant-induced jitteriness/anxiety syndrome: systematic review.

BACKGROUND: Early worsening of anxiety, agitation and irritability are thought to be common among people commencing antidepressants, especially for anxiety disorders. This phenomenon, which may be termed jitteriness/anxiety syndrome, is cited as an explanation for early treatment failure and caution in using selective serotonin reuptake inhibitors (SSRIs). However, we believe that it is inconsistently defined and that robust evidence to support the phenomenon is lacking. AIMS: To review systematically all evidence relating to jitteriness/anxiety syndrome to identify: constituent symptoms; medications implicated; disorders in which it was reported; incidence; time course; management strategies; relationship of this syndrome to therapeutic response; distinction between syndrome and akathisia; relationship between syndrome and suicide; and genetic predispositions. METHOD: A systematic search identified articles and these were included in the review if they addressed one of the above aspects of jitteriness/anxiety syndrome. RESULTS: Of 245 articles identified, 107 articles were included for review. No validated rating scales for jitteriness/anxiety syndrome were identified. There was no robust evidence that the incidence differed between SSRIs and tricyclic antidepressants, or that there was a higher incidence in anxiety disorders. Published incidence rates varied widely from 4 to 65% of people commencing antidepressant treatment. Common treatment strategies for this syndrome included a slower titration of antidepressant and the addition of benzodiazepines. Conclusive evidence for the efficacy of these strategies is lacking. There was conflicting and inconclusive evidence as to whether the emergence of this syndrome had a predictive value on the response to treatment. It appears to be a separate syndrome from akathisia, but evidence for this assertion was limited. The effect of jitteriness/anxiety syndrome on suicide rates has not been evaluated. Three studies examined genetic variations and side-effects from treatment, but none was specifically designed to assess jitteriness/anxiety syndrome. CONCLUSIONS: Jitteriness/anxiety syndrome remains poorly characterised. Despite this, clinicians' perception of this syndrome influences prescribing and it is cited to support postulated mechanisms of drug action. We recommend systematised evaluation of side-effects at earlier time points in antidepressant trials to further elucidate this clinically important syndrome.

PRN prescribing in psychiatric inpatients: potential for pharmacokinetic drug interactions.

Medications are commonly prescribed to psychiatric inpatients on a PRN (pro re nata/as required) basis, allowing drugs to be administered on patient request or at nurses' discretion for psychiatric symptoms, treatment side effects or physical complaints. However, there has been no formal study of the pharmacokinetic implications of PRN prescribing. The objective of the study was to determine the prevalence of PRN drug prescription and administration, and to assess the potential for interactions involving CYP2D6 and CYP3A4 between drugs prescribed and administered to inpatients on psychiatry wards.A cross-sectional survey of prescriptions on general adult and functional elderly psychiatric wards in one city was carried out. Data were recorded from prescription charts of 323 inpatients (236 on general adult and 87 on functional elderly wards). Of 2089 prescriptions, 997 (48%) of prescriptions were on a PRN basis (most commonly benzodiazepines and other hypnotic agents, antipsychotics, analgesics and anticholinergic agents), but only 143 (14%) of these had been administered in the previous 24 hours. One fifth of patients were prescribed drug combinations interacting with CYP2D6 or CYP3A4 of potential clinical importance which included one or more drugs prescribed on a PRN basis.PRN prescribing is common among inpatients in psychiatry, and may lead to cytochrome P450 mediated interactions. Prescribers should be aware of the potential for unpredictability in plasma concentrations, side effects and efficacy which PRN prescribing may cause through these interactions, particularly in old age psychiatry and in treatment of acute psychosis.

Modification of de novo DNA methyltransferase 3a (Dnmt3a) by SUMO-1 modulates its interaction with histone deacetylases (HDACs) and its capacity to repress transcription.

The de novo DNA methyltransferase Dnmt3a is one of three mammalian DNA methyltransferases that has been shown to play crucial roles in embryonic development, genomic imprinting and transcriptional silencing. Despite its importance, very little is known about how the enzymatic activity and transcriptional repression functions of Dnmt3a are regulated. Here we show that Dnmt3a interacts with multiple components of the sumoylation machinery, namely the E2 sumo conjugating enzyme Ubc9 and the E3 sumo ligases PIAS1 and PIASxalpha, all of which are involved in conjugating the small ubiquitin-like modifier polypeptide, SUMO-1, to its target proteins. Dnmt3a is modified by SUMO-1 in vivo and in vitro and the region of Dnmt3a responsible for interaction maps to the N-terminal regulatory domain. Functionally, sumoylation of Dnmt3a disrupts its ability to interact with histone deacetylases (HDAC1/2), but not with another interaction partner, Dnmt3b. Conditions that enhance the sumoylation of Dnmt3a in vivo abolish its capacity to repress transcription. These studies reveal a new level of regulation governing Dnmt3a whereby a post-translational modification can dramatically regulate its interaction with specific protein partners and alter its ability to repress transcription.

Isolation and characterization of a novel DNA methyltransferase complex linking DNMT3B with components of the mitotic chromosome condensation machinery.

Proper patterns of genome-wide DNA methylation, mediated by DNA methyltransferases DNMT1, -3A and -3B, are essential for embryonic development and genomic stability in mammalian cells. The de novo DNA methyltransferase DNMT3B is of particular interest because it is frequently overexpressed in tumor cells and is mutated in immunodeficiency, centromere instability and facial anomalies (ICF) syndrome. In order to gain a better understanding of DNMT3B, in terms of the targeting of its methylation activity and its role in genome stability, we biochemically purified endogenous DNMT3B from HeLa cells. DNMT3B co-purifies and interacts, both in vivo and in vitro, with several components of the condensin complex (hCAP-C, hCAP-E and hCAP-G) and KIF4A. Condensin mediates genome-wide chromosome condensation at the onset of mitosis and is critical for proper segregation of sister chromatids. KIF4A is proposed to be a motor protein carrying DNA as cargo. DNMT3B also interacts with histone deacetylase 1 (HDAC1), the co-repressor SIN3A and the ATP-dependent chromatin remodeling enzyme hSNF2H. Further more, DNMT3B co-localizes with condensin and KIF4A on condensed chromosomes throughout mitosis. These studies therefore reveal the first direct link between the machineries regulating DNA methylation and mitotic chromosome condensation in mammalian cells.

Effects of mouse strain, position of integration and tetracycline analogue on the tetracycline conditional system in transgenic mice.

The tetracycline conditional system is a very powerful method for achieving control of gene expression in transgenic mice, allowing one to turn expression both off and on in the same animal. We have used it to make a tissue-specific transgenic mouse model of Charcot-Marie-Tooth disease type 1A. This disease is most commonly caused by overexpression of peripheral myelin protein 22 (PMP22) in Schwann cells of the peripheral nervous system. Here we describe the effects of position of integration of the transgene, tetracycline analogue and mouse strain in this model. The small transgenes used to express tTA, the LacZ reporter and the pmp22 cDNA were all very dependent on the position of integration with few of the transgenic lines working successfully. In contrast, the single transgenic made with the 560 kb yeast artificial chromosome construct containing the tTA open reading frame worked well. Tetracycline was found to be cleared from mice relatively fast in comparison with doxycycline and is thus useful if one wants to switch on gene expression after extended periods of administration. Finally, the initial litters were on a mixed genetic background and the level of LacZ or pmp22 expression was very variable between mice. We found that expression became uniform between mice, and occurred in a higher proportion of cells, when the transgenes were crossed onto the CBA/Ca background in comparison with the C57BL/6J background.

Randomized trial of teaching brief motivational interviewing to pediatric trainees to promote healthy behaviors in families.

HYPOTHESIS: That pediatric resident trainees would demonstrate increased counseling skill following training in brief motivational interviewing (MI). DESIGN: Randomized controlled trial. SETTING: University of Washington Pediatric Residency. PARTICIPANTS: Pediatric residents (N = 18), including residents in postgraduate years 1, 2, 3, and 4. INTERVENTIONS: Collaborative Management in Pediatrics, a 9-hour behavior change curriculum based on brief MI plus written feedback on communication skills (based on a 3-month Objective Standardized Clinical Evaluation [OSCE]). MAIN OUTCOME MEASURE: The percentage of MI-consistent behavior (%MICO), a summary score for MI skill, was assessed via OSCEs in which standardized patients portray parents of children with asthma in 3 clinical scenarios (stations). The OSCEs were conducted at baseline and 3 and 7 months. Blinded coders rated videotaped OSCEs using a validated tool to tally communication behaviors. Training effects were assessed using linear regression controlling for baseline %MICO. Global ratings of counseling style served as secondary outcome measures. RESULTS: Trained residents demonstrated a trend toward increased skill (%MICO score) at 3 months compared with control residents. At 7 months, %MICO scores increased 16% to 20% (P < .02) across all OSCE stations after the combined intervention of Collaborative Management in Pediatrics training plus written feedback. The effect of training on global ratings supported the main findings. CONCLUSIONS: Pediatric trainees' skills in behavior change counseling improved following the combination of training in brief MI plus personalized feedback.

Pediatric hospital adherence to the standard of care for acute gastroenteritis.

BACKGROUND: Adherence to published care guidelines for the management of acute gastroenteritis (AGE) is unknown. OBJECTIVES: To evaluate the association of AGE guideline adherence with outcomes and resource use at pediatric hospitals. DESIGN/METHODS: We studied children aged 6 months to 6 years with an International Classification of Diseases, Ninth Edition (ICD-9) discharge code indicative of AGE and without comorbid conditions in the emergency department, observation setting, or hospital. Laboratory studies, antiemetic use, and antibiotic use were evaluated, and the length of stay, mean adjusted total charges, and readmission proportion were documented. Multiple analysis of variance determined if the variance of adjusted charges, length of stay, and diagnostic studies were hospital-related. A regression analysis determined the association between guideline adherence and outcomes. RESULTS: There were a total of 188873 patients; 174594 (92.4%) were not admitted, and 14279 (7.6%) were admitted. There was substantial variation in resource use among hospitals. The mean adjusted total charge for all patients was $863 (SD: 1336). The mean adjusted total charge for nonadmitted patients was $591 (SD: 636). Individual hospitals contributed to the variance of mean length of stay, total adjusted charges, and use of diagnostic studies after controlling for covariates (P < .001). Guideline adherence was associated with a mean decrease in the average adjusted cost ($591) for nonadmitted patients of $296 (95% confidence interval: -399 to -193). CONCLUSIONS: Guideline-adherent hospitals demonstrated 50% lower charges for emergency department or observation patients with uncomplicated AGE without adversely affecting outcomes. Use of resources not routinely recommended by published AGE guidelines remains common in pediatric hospitals.

Preventive dental care for young, Medicaid-insured children in Washington state.

BACKGROUND: Children from low-income families face barriers to preventive dental care (PDC) and are disproportionately affected by dental caries. The Access to the Baby and Childhood Dentistry (ABCD) program of Washington State is targeted to Medicaid-insured children <6 years of age to improve their access to PDC. OBJECTIVES: To test the hypothesis that residing in an ABCD county improves the likelihood of receiving PDC and, to compare PDC use among young, Medicaid-insured children in Washington to national statistics. METHODS: We extracted 2003 Washington Medicaid dental claims for continuously enrolled children or=1 preventive dental visit (PDV) in 2003. For national comparison, we used the 2003 Medical Expenditure Panel Survey (MEPS). RESULTS: Among Medicaid-insured children or=1 PDV in 2003. We also found that significantly more children in established ABCD counties received PDC compared with privately insured US children. These findings provide additional evidence that the ABCD program reduces disparities in dental care access among young, Medicaid-insured children in Washington and point to the importance of expanding the ABCD program to other states.

Hospital-based influenza vaccination of children: an opportunity to prevent subsequent hospitalization.

OBJECTIVE: We performed this study to determine the frequency of previous hospitalization among children hospitalized with influenza. METHODS: The Pediatric Health Information System database (discharges that occurred between January 1, 2001, and December 31, 2006) was used to determine the proportion of children hospitalized with influenza or respiratory illness who had a previous hospitalization during the most recent influenza-vaccination season. Subjects included pediatric patients (through 18 years of age). The index hospitalization was defined as the first influenza or respiratory illness hospitalization for a child that occurred during the study period and between November 1 and April 30. A previous hospitalization during the most recent influenza-vaccination season was defined as a hospitalization for any reason in the 0.5 to 6 months before the index hospitalization but not before September 1 or on or after March 1. RESULTS: Overall, 16% of children hospitalized with influenza and 12% of children hospitalized with influenza or a respiratory illness had a previous hospitalization during the most recent influenza-vaccination season. Approximately 23% of the children hospitalized with influenza and a comorbidity had a previous hospitalization during the most recent influenza-vaccination season. CONCLUSION: Hospital-based programs for influenza vaccination have the potential to reach children at highest risk of influenza complications and to reduce the rates of pediatric hospitalization for treatment of influenza-related illness.

SREBP-2 and SCAP isoforms and risk of early onset myocardial infarction.

BACKGROUND: Cholesterol metabolism is mediated, in part, by the sterol-regulatory element binding proteins (SREBPs) that are activated by a SREBP cleavage-activating protein (SCAP). We examined whether coding variations in the interacting domains of both genes, are related to early-onset MI risk in a population-based case-control study from western Washington State. METHODS: Cases were 257 women, aged 18-59 years, and 320 men, aged 18-49 years, with first acute non-fatal MI; controls were 353 women and 311 men, similar in age, identified from the community who had no history of clinical CHD or stroke. Genotyping of the SREBF-2 G1784C polymorphism (SREBP-2-595A/G isoforms), and the SCAP A2386G polymorphism (SCAP-796I/V isoforms), were performed. RESULTS: After adjustment for age and race, the SREBP-2-595A isoform was associated with increased MI risk among men (OR=1.63, 95% CI=1.26-2.12). In contrast, there was little evidence for an association among women in a multiplicative model. However, compared to SREBP-2-595G homozygotes, homozygote women for the SREBP-2-595A isoform were at nearly two-fold increased risk (OR=1.95, 95% CI=1.07-3.54). Overall, SCAP genotypes were neither associated with MI in men nor in women. However, in men, SCAP genotypes were found to modify the association between SREBF-2 and MI (p-value for interaction=0.01). CONCLUSION: The SREBP-2-595A isoform was associated with an increased risk of early-onset MI in U.S. men. The SCAP polymorphism appeared to modify the associations of SREBF-2 genotype with MI risk among men. These novel findings require confirmation in other populations.

Unmet dental care needs among children with special health care needs: implications for the medical home.

BACKGROUND: Little is known about the characteristics of children with special health care needs (CSHCN) who have unmet dental care needs. OBJECTIVE: We sought to describe the magnitude of unmet needs for dental care among CSHCN and to characterize those with unmet dental care needs. DESIGN, SETTING, AND SUBJECTS: We used data from the National Survey of Children with Special Health Care Needs, which used a telephone survey to identify 750 CSHCN from each of the 50 states and the District of Columbia. Families of 38,866 CSHCN were interviewed, and the data were weighted to represent 9.32 million CSHCN nationally. OUTCOME: Our primary outcome of interest was unmet dental care need, defined as whether CSHCN were said to have needed dental care but were unable to obtain it. We also considered reasons why a child had an unmet dental care need and compared other categories of health care service needs and unmet needs with dental care. Bivariate and multivariate analyses were conducted to determine factors associated with unmet dental care needs. RESULTS: Overall, 78% of CSHCN were reported as needing dental care in the past 12 months, which was second only to prescription medications in the frequency of need. Of those who reported a dental care need, an estimated 755,581 or 10.4% of CSHCN did not receive all of the dental care they needed. Relative to all other health care service categories, unmet dental care needs affected the most children. Poorer children, uninsured children, children with lapses in insurance, and children with greater limitations attributable to disability had significantly greater odds of unmet dental care needs in multivariate analyses. Children with a personal doctor or nurse were significantly less likely to have unmet dental care needs. CONCLUSIONS: Dental care is the most prevalent unmet health care need for CSHCN, affecting substantially more children than any other health care need category. Moreover, the perceived need for dental care for CSHCN exceeds the need for either preventive or specialty medical care. Given these findings, dental care should be an integral and explicitly stated part of the comprehensive coordinated services that the medical home aims to provide for CSHCN. Greater efforts to improve access to dental care for poor and more disabled CSHCN are needed.

Effects of chromatin structure on the enzymatic and DNA binding functions of DNA methyltransferases DNMT1 and Dnmt3a in vitro.

DNA methylation is an epigenetic modification of the genome critical for numerous processes, including transcriptional repression and maintenance of chromatin structure. Recent studies have revealed connections between DNA methylation and other epigenetic modifications such as ATP-dependent chromatin remodeling. It remains unclear, however, exactly how chromatin and epigenetic chromatin modifications affect the biological properties of the DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B). Using a highly purified system and the 5S rDNA gene as free DNA or assembled into a mononucleosome, we have compared the effects of chromatin structure on DNMT1 and Dnmt3a. The catalytic efficiency for both enzymes decreased on the mononucleosome, approximately 8-fold for DNMT1 and 17-fold for Dnmt3a. DNMT1 and Dnmt3a bound to DNA and mononucleosomal substrates in gel shift experiments with approximately equal affinity and in a cooperative manner. We also show that DNMT1 interacts with hSNF2H chromatin remodeling enzyme and that DNMT1 binds mononucleosomes with higher affinity in the presence of hSNF2H. These findings raise interesting implications about the interactions of mammalian DNA methyltransferases with chromatin and provide the first evidence that a chromatin remodeling enzyme can alter the biological properties of a DNMT.

DNMT3B interacts with hSNF2H chromatin remodeling enzyme, HDACs 1 and 2, and components of the histone methylation system.

The non-random pattern of genome-wide DNA methylation in mammalian cells is established and maintained by DNA methyltransferases DNMT1, 3A, and 3B. De novo DNA methyltransferase DNMT3B is critical for embryonic development and is mutated in ICF syndrome. Despite its importance in normal cellular functioning, little is known about how DNMT3B operates in the context of chromatin. Here we demonstrate that DNMT3B associates with four chromatin-associated enzymatic activities common to transcriptionally repressed, heterochromatic regions of the genome: DNA methyltransferase, histone deacetylase, ATPase, and histone methylase activities. By immunoprecipitation and GST pull-down, we show that DNMT3B interacts with HDAC1, HDAC2, HP1 proteins, Suv39h1, and the ATP-dependent chromatin remodeling enzyme hSNF2H. Endogenous hSNF2H is also associated with DNA methyltransferase activity. These proteins co-localize extensively with DNMT3B in heterochromatic regions. Our results therefore link DNMT3B to three other components of the epigenetic machinery and provide important insights into how DNA methylation patterns may be established within the chromatin environment.

Calcium, vitamin D, dairy products, and risk of colorectal cancer in the Cancer Prevention Study II Nutrition Cohort (United States).

OBJECTIVE: Calcium, vitamin D, and dairy product intake may reduce the risk of colorectal cancer. We therefore examined the association between these factors and risk of colorectal cancer in a large prospective cohort of United States men and women. METHODS: Participants in the Cancer Prevention Study II Nutrition Cohort completed a detailed questionnaire on diet, medical history, and lifestyle in 1992-93. After excluding participants with a history of cancer or incomplete dietary information, 60,866 men and 66,883 women remained for analysis. During follow-up through 31 August 1997 we documented 421 and 262 cases of incident colorectal cancers among men and women, respectively. Multivariate-adjusted rate ratios (RR) were calculated using Cox proportional hazards models. RESULTS: Total calcium intake (from diet and supplements) was associated with marginally lower colorectal cancer risk in men and women (RR = 0.87, 95% CI 0.67-1.12, highest vs lowest quintiles, p trend = 0.02). The association was strongest for calcium from supplements (RR = 0.69, 95% CI 0.49-0.96 for > or = 500 mg/day vs none). Total vitamin D intake (from diet and multivitamins) was also inversely associated with risk of colorectal cancer, particularly among men (RR = 0.71, 95% CI 0.51-0.98, p trend = 0.02). Dairy product intake was not related to overall risk. CONCLUSIONS: Our results support the hypothesis that calcium modestly reduces risk of colorectal cancer. Vitamin D was associated with reduced risk of colorectal cancer only in men.