National Experiences from 30 Years of Provider-Mediated Cascade Testing in Lynch Syndrome Families-The Danish Model

Cascade genetic testing and surveillance reduce morbidity and mortality in Lynch syndrome. However, barriers to conveying information about genetic disorders within families result in low uptake of genetic testing. Provider-mediated interventions may increase uptake but raise legal and ethical concerns. We describe 30 years of national experience with cascade genetic testing combining family- and provider-mediated contact in Lynch syndrome families in the Danish Hereditary Non-Polyposis Colorectal Cancer (HNPCC) Register. We aimed to estimate the added value of information letters to family members in Lynch syndrome families (provider-mediated contact) compared to family members not receiving such letters and thus relying on family-mediated contact. National clinical practice for cascade genetic testing, encompassing infrastructure, legislation, acceptance, and management of the information letters, is also discussed. Cascade genetic testing resulted in 7.3 additional tests per family. Uptake of genetic testing was 54.4% after family-mediated and 64.9% after provider-mediated contact, corresponding to an odds ratio of 1.8 (p < 0.001). The uptake of genetic testing was highest in the first year after diagnosis of Lynch syndrome in the family, with 72.5% tested after provider-mediated contact. In conclusion, the Danish model combining family- and provider-mediated contact can increase the effect of cascade genetic testing.

Dialogue is a prerequisite for the nurse-patient relationship in nutritional care: A secondary analysis using the fundamentals of care framework

BACKGROUND

Providing good nutritional care is complex as it goes beyond assessing and ensuring the patients' dietary needs. So far, nutritional research has mainly focused on establishing evidence for the nutritional treatment, while less attention has been on the complexity of providing nutritional care. The Fundamentals of Care (FoC) describes five elements (focus, knowledge, anticipate, evaluate and trust) essential for establishing a nurse-patient relationship as a foundation for quality care. By studying how these elements shape nutritional care and dialogue, we can explore and describe the complexity of nutritional care.

AIM

By using the FoC framework as an analytic framework, this study explores how the nurse-patient relationship shapes the nutritional care of orthopaedic patients.

METHOD

This study is a secondary analysis using deductive content analysis of interviews with patients undergoing major orthopaedic surgery, nursing staff and observations of interactions between nursing staff and patients. The core dimension of the FoC framework, 'Establishment of relationship,' was used as an analytic framework.

RESULT

The nurses perceived serving meals and providing nutritional supplements as an essential part of the nutritional care. Still, the nutritional care was organised as a routine task to be less time-consuming. Appropriate care was initiated when the nursing staff explored patients´ food preferences. When the nursing staff failed to familiarise themselves with the patient's preferences, the patients interpreted nutritional care as unrelated to their needs, resulting in a lack of trust.

CONCLUSION

The need for efficiency within nutritional care must not compromise the patients' need for dialogue with the nurse. Establishing a trusting relationship between nurses and patients prevents nutritional care from becoming a routine task unrelated to the patients' needs.

From expected to actual barriers and facilitators when implementing a new screening tool: A qualitative study applying the Theoretical Domains Framework

AIM AND OBJECTIVES

To identify determinants for using a new screening tool to identify older patients eligible for targeted nurse-led intervention, as perceived by healthcare professionals implementing the tool, and to examine how these perceptions changed over time.

DESIGN

A cross-sectoral longitudinal qualitative study based on semi-structured interviews with healthcare professionals in a Danish hospital and two collaborating municipalities.

METHODS

In three focus groups, seven single interviews and a workshop, we examined the healthcare professionals' perceptions of and attitudes towards the new screening tool before, during and after the implementation. The Theoretical Domains Framework was used to identify the healthcare professionals' perception of barriers and facilitators, followed by content analysis. The results were further discussed using the COM-B system as an analytic framework. This qualitative study is reported according to the Consolidated Criteria for Reporting Qualitative Studies (COREQ) checklist.

RESULTS

'Professional role', 'Goals' and 'Environmental context' were the domains most talked about by the healthcare professionals across the three time points. The content analysis identified four determinants for using the new screening tool:Making time for the project, External motivation and management, Expectations and reality, and Professional identity. The healthcare professionals' perception of the determinants changed during the implementation, influencing their behaviour and, consequently, the implementation's sustainability.

CONCLUSION

Perception of barriers and facilitators to the interventions were time- and context-sensitive. Beliefs and motivational factors changed during the project, which points out the importance of following implementation processes systematically to understand the outcome of an intervention.

RELEVANCE FOR CLINICAL PRACTICE

Perceptions and attitudes towards a new initiative may change over time, emphasising the importance of following barriers and facilitators during the implementation of an intervention and working with an implementation plan that can be adapted along the way.

Surveillance life and the shaping of 'genetically at risk' chronicities in Denmark

Today, in the field of hereditary colorectal cancer in Denmark, more than 40,000 identified healthy individuals with an increased risk of cancer are enrolled in a surveillance program aimed at preventing cancer from developing, with numbers still growing. What this group of healthy individuals has in common is lifelong regular interaction with a healthcare system that has traditionally been geared towards treating the acutely and chronically ill. In this article, we explore how people living with an inherited elevated risk of colorectal cancer orient themselves towards their families' and their own predispositions as well as the lifelong surveillance trajectories that they have embarked upon - what we call surveillance life. Unlike prior critiques of predictive genetic testing as generative of 'pre-patients' or 'pre-symptomatically ill', we suggest that for those enrolled in lifelong surveillance programmes in welfare state Denmark, the relevance of risk fluctuates according to certain moments in life, e.g. at family reunions, when a close relative falls ill, in the time leading up to a surveillance colonoscopy or when enduring the procedures themselves. As such, rather than characterising surveillance life in terms of 'living with chronic risk' we show how 'genetically at risk' chronicities take shape as persons come to terms with a disease that possibly awaits them leading them to recalibrate familial bonds and responsibilities while leading lives punctuated by regular medical check-ups.

"It is two worlds" cross-sectoral nurse collaboration related to care transitions: A qualitative study

AIMS AND OBJECTIVES

To explore how the hospital and home care nurses talk about and experience cross-sectoral collaboration related to the transitional care of frail older patients.

BACKGROUND

Effective communication and collaboration between nurses involved in care transition are crucial for a safe patient handover. Organisational systems to support cross-sectoral collaboration have been developed but do not always promote the intended dialogue and precise and useful exchange of information. Other factors may also be of importance to an effective and constructive cross-sectoral nurse collaboration.

DESIGN

A qualitative design using thematic analysis.

METHODS

Data were extracted from 24 focus group interviews conducted with registered nurses from eight hospital wards and six municipalities and a total of 165 hr of observations conducted in three hospital wards and three municipalities. The study was reported according to the COREQ guidelines.

RESULTS

The perception of nursing and care differed across sectors. The nurses expressed having shared goals for the patients-however, these goals derived from different values, the perception of nursing and approach to the patients. The lack of knowledge of each other's working conditions created assumptions and preconceptions, which affected communication and collaboration related to planning and executing care transition negatively.

CONCLUSIONS

The nurses perceived the hospital and home care as" two worlds". The collaboration between the nurses was characterised by insufficient communication and preconceptions rather than concrete knowledge and different cultures and professional identities. It can be questioned whether cross-sectoral collaboration between nurses should be characterised as interprofessional rather than intraprofessional collaboration as the features of the nurses' collaboration.

RELEVANCE TO CLINICAL PRACTICE

Organisational and political systems should recognise that nurses in different sectors are taking care of various aspects of nursing when planning on policies to support cross-sectoral collaboration. More possibilities for nurses across sectors to meet should be made available.

Nurses' perspectives on how an e-message system supports cross-sectoral communication in relation to medication administration: A qualitative study

AIMS AND OBJECTIVES

To describe nurses' perspectives on how an e-message system supports communication between hospital and home care nurses in relation to medication administration.

BACKGROUND

Medication administration is a complex process involving a high risk of error. Unclear communication and lack of updated information about medication have been identified as the leading cause of medication errors during care transitions. E-message systems are progressively being used to improve information exchange across sectors, yet little is known about their usage for exchange of medication information between nurses.

DESIGN

A qualitative design using content analysis.

METHODS

Focus group interviews were conducted with nurses from eight hospital wards and six municipalities (n = 79). Participant observations were conducted in three hospital wards and in three municipalities (165 hr).

RESULTS

The e-message system did not provide the information needed by the home care nurses to ensure safe medication administration after discharge due to (1) limitations of the system, (2) hospital nurses' lack of knowledge about home care nurses' information needs and (3) hospital nurses' lack of access to medication information. Due the home care nurses' perception of responsibility, they bypassed the e-message system to get the information.

CONCLUSIONS

The home care nurses perceived themselves as the last link in the safety chain. As such, access to adequate information was essential for the nurses to ensure safe medication administration; however, the e-message system did not support exchange of the information needed.

RELEVANCE TO CLINICAL PRACTICE

E-message systems must meet home care nurses' need for information to ensure that safe medication administration does not depend on the knowledge of the individual nurse. Moreover, other system factors that influence interprofessional collaboration and nurses' cross-sectoral communication must be addressed.

Stuck in tradition-A qualitative study on barriers for implementation of evidence-based nutritional care perceived by nursing staff

AIMS AND OBJECTIVES

To explore the barriers for nutritional care as perceived by nursing staff at an acute orthopaedic ward, aiming to implement evidence-based nutritional care.

BACKGROUND

Previous studies indicate that nurses recognise nutritional care as important, but interventions are often lacking. These studies show that a range of barriers influence the attempt to optimise nutritional care. Before the implementation of evidence-based nutritional care, we examined barriers for nutritional care among the nursing staff.

DESIGN

Qualitative study.

METHODS

Four focus groups with thirteen members of the nursing staff were interviewed between October 2013-June 2014. The interview guide was designed according to the Theoretical Domains Framework. The interviews were analysed using qualitative content analysis.

RESULTS

Three main categories emerged: lacking common practice, failing to initiate treatment and struggling with existing resources. The nursing staff was lacking both knowledge and common practice regarding nutritional care. They felt they protected patient autonomy by accepting patient's reluctance to eat or getting a feeding tube. The lack of nutritional focus from doctors decreased the nursing staffs focus leading to nonoptimal nutritional treatment. Competing priorities, physical setting and limited nutritional supplements were believed to hinder nutritional care.

CONCLUSION

The results suggest that nutritional care is in a transitional state from experience- to evidence-based practice. Barriers for nutritional care are grounded in lack of knowledge among nursing staff and insufficient collaboration between nursing staff and the doctors. There is a need for nutritional education for the nursing staff and better support from the organisation to help nursing staff provide evidence-based nutritional care.

RELEVANCE TO CLINICAL PRACTICE

This study contributes with valuable knowledge before the implementation of evidence-based nutritional care. The study provides an understanding of barriers for nutritional care and presents explanations to why nutritional care has failed to become an integrated part of the daily treatment and care.

Sense of coherence and self-concept in Lynch syndrome

Objective

Most individuals who learn about hereditary cancer manage well, but identification of subgroups who find this knowledge burdening would allow psychosocial intervention. The objective of the study was to assess sense of coherence (SOC) in individuals with Lynch syndrome with comparison to a general population and correlation to self-concept.

Methods

A total of 345 individuals with Lynch syndrome completed the 13-item SOC scale and the 20-item Lynch syndrome self-concept scale. SOC scores were compared to a general Danish population and were correlated to self-concept estimates in individuals with Lynch syndrome. Characteristics of subgroups with adverse scores were described.

Results

Individuals with Lynch syndrome reported SOC scores similar to the general population. SOC and self-concept correlated well with a correlation coefficient of −0.51. Subsets with convergent and divergent scores, which may reflect different effects from knowledge about hereditary cancer, were identified.

Conclusion

Individuals with Lynch syndrome report SOC scores similar to the general population. SOC and self-concept correlate well but allow identification of subset who report adverse outcome and may be relevant for targeted intervention.

Development and validation of an instrument to measure the impact of genetic testing on self-concept in Lynch syndrome

A positive genetic test result may impact on a person's self-concept and affect quality of life. The purpose of the study was to develop a self-concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer Lynch syndrome (LS). Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors, which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers, Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. A 20-item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale showed excellent reliability (Cronbach's α = 0.93), good convergent validity by a high correlation with impact of event scale (r(102) = 0.55, p < 0.001) and Rosenberg self-esteem scale (r(108) = -0.59, p < 0.001), and a low correlation with the Fear questionnaire (r(108) = 0.37, p < 0.001). The scale's performance was stable across participant characteristics. This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies.

Characterization of the rat GAD67 gene promoter reveals elements important for basal transcription and glucose responsiveness

GAD65 and GAD67 are two isoforms of the enzyme glutamic acid decarboxylase which catalyze the production of GABA from glutamate, primarily in the brain. However, GAD and GABA also prevail in the retina, testes and islets of Langerhans. The main function of GABA is in neurotransmission, and it is involved in paracrine signalling in islets, but has also been suggested to play a role as a trophic factor in synaptogenesis and to be an important metabolite feeding into the tricarboxylic acid cycle via the GABA-shunt. Both GAD isoforms are subject to regulation, e.g. by synaptic activity. GAD65 is regulated at the level of enzyme activity by association and dissociation from its cofactor, PLP, whereas GAD67 is controlled at the level of its mRNA. To study this process in further detail, we have isolated and characterized the 5'-flanking region of the rat GAD67 gene. We report the transcriptional initiation sites and promoter sequences important for expression in islet beta-cells and C6 glioma cells, and demonstrate that the GAD67 promoter harbors elements that are responsive to glucose in primary islet cells.

The excess costs of breast cancer health care in Hispanic and non-Hispanic female members of a managed care organization

The differences in costs for health care services between women with breast cancer and those without were estimated for Hispanic and non-Hispanic members of a managed care organization. A total of 317 cases of breast cancer and 949 controls were selected using a comprehensive patient database. All health care costs for the 4-12 months prior to the case's diagnosis and for the 12 months following the case's diagnosis were obtained. Costs were defined as charges to the health plan. Mean differences in total health care costs between cases and controls were predicted using Tobit models for 4-12 months prior to diagnosis and the year after diagnosis by age group. Compared to controls, women diagnosed with in situ breast cancers in all age groups had significantly higher health care costs 4-12 months prior to diagnosis. For women under 50 years of age, the difference in costs for cases compared to controls 12 months after diagnosis was almost three times greater for women with regional/distant disease ($17,093 +/- $1,559) compared to in situ disease ($5,089 +/- $1,050). For women in the two other age groups (50-70 years and over 70 years), the difference was over twice as great for those with regional/distant disease compared to those with in situ disease. Mean differences between cases and controls in health care costs 12 months after diagnosis were similar for Hispanic and non-Hispanic women for all stages of disease.

Mammography utilization after a benign breast biopsy among Hispanic and non-Hispanic women

BACKGROUND

In spite of the effectiveness of mammography screening for early detection of breast carcinoma, the use of screening mammography varies widely across racial and ethnic groups. Recently, concerns have been raised about the potential adverse effect a benign breast biopsy may have on subsequent mammography utilization, including subsequent use among minority women.

METHODS

Computerized health care claims data for 1991 through 1997 from a managed care organization were used to compare mammography use among Hispanic and non-Hispanic women who had had a mammogram followed by an incisional or excisional benign breast biopsy to women who had had a mammogram and no biopsy. Through survival analysis methods, the time-to-next mammogram was compared among these three groups.

RESULTS

The sample included 693 (3.2%) and 289 (1.3%) women who had had a mammogram followed by an incisional biopsy or an excisional biopsy, respectively, and 20,540 (95.4%) women who had had a mammogram and no biopsy. Both Hispanic and non-Hispanic women with a biopsy returned sooner for subsequent mammograms than women without a biopsy (P < 0.0001). Hispanic women without a biopsy returned later than non-Hispanic women without a biopsy (P < 0.0001). However, Hispanic women with an excisional biopsy returned sooner than non-Hispanic women (P < 0.05).

CONCLUSIONS

Within a managed care organization, both Hispanic and non-Hispanic women who had had a mammogram followed by a benign breast biopsy returned sooner for a subsequent mammogram than women who had had a mammogram and no biopsy. However, ethnic differences in time-to-next mammogram were observed for women without a biopsy and those with an excisional biopsy. Hispanic women without a biopsy returned later for a subsequent mammogram than non-Hispanic women in similar groups, but those with an excisional biopsy returned sooner.

The PDX-1 activation domain provides specific functions necessary for transcriptional stimulation in pancreatic beta-cells

PDX-1 is a homeodomain transcription factor whose targeted disruption results in a failure of the pancreas to develop. Mutations in the human pdx-1 gene are linked to an early onset form of non-insulin-dependent diabetes mellitus. PDX-1 binds to and transactivates the promoters of several physiologically relevant genes within the beta-cell, including insulin, glucose transporter 2, glucokinase, and islet amyloid polypeptide. This study focuses on the mechanisms by which PDX-1 activates insulin gene transcription. To evaluate the role of PDX-1 in transcription of the insulin gene, a chloramphenicol acetyltransferase reporter construct was designed with a single yeast GAL4-DNA binding site in place of the A3/PDX-1 binding element in the rat insulin II enhancer. In the presence of GAL4:PDX chimeras containing N-terminal transactivation domain sequences, this GAL4-substituted insulin construct was active in PDX-1-expressing beta-cells and not non-beta-cells. PDX-1 activation was mediated through three highly conserved segments of the transactivation domain. In addition, when cotransfected together with the GAL4-substituted insulin enhancer reporter gene in glucose-responsive MIN-6 beta-cells, glucose-induced activation is observed with GAL4:PDX-1 but not with fusions of the heterologous activation domains from herpes virus VP16 or adenovirus-5 E1A proteins. Using A3 element-substituted GAL4 insulin enhancer reporter constructs containing mutations in two additional key control elements, E1 and C1, we also show that full activation requires cooperative interactions between other enhancer-bound factors, particularly the E1 element activators. In contrast, the activity of the VP16 activation factor was not dependent on the activators of either the E1 or C1 sites. These results suggest that the PDX-1 transactivation domain is specifically required for appropriate regulation of insulin enhancer function in beta-cells.

Health care utilization in chronic obstructive pulmonary disease. A case-control study in a health maintenance organization

BACKGROUND

Information about health care utilization and costs among patients with chronic obstructive pulmonary disease (COPD) is needed to improve care and for appropriate allocation of resources for patients with COPD (COPD patients or cases) in managed care organizations.

METHODS

Analysis of all inpatient, outpatient, and pharmacy utilization of 1522 COPD patients continuously enrolled during 1997 in a 172,484-member health maintenance organization. Each COPD case was matched with 3 controls (n = 4566) by age (+/-5 years) and sex. Information on tobacco use and comorbidities was obtained by chart review of 200 patients from each group.

RESULTS

Patients with COPD were 2.3 times more likely to be admitted to the hospital at least once during the year, and those admitted had longer average lengths of stay (4.7 vs 3.9 days; P<.001). Mean costs per case and control were $5093 vs $2026 for inpatient services, $5042 vs $3050 for outpatient services, and $1545 vs $739 for outpatient pharmacy services, respectively (P<.001 for all differences). Patients with COPD had a longer smoking history (49.5 vs 34.9 pack-years; P =.002) and a higher prevalence of smoking-related comorbid conditions and were more likely to use cigarettes during the study period (46.0% vs 13.5%; P<.001).

CONCLUSIONS

Health care utilization among COPD patients is approximately twice that of age- and sex-matched controls, with much of the difference attributable to smoking-related diseases. In this health maintenance organization, inpatient costs were similar to and outpatient costs were much higher than national averages for COPD patients covered by Medicare.

A comparison of two methods for estimating the health care costs of epilepsy

PURPOSE

Previous studies have estimated medical care costs of epilepsy by applying unit costs to estimated utilization or by summing costs for (a) ambulatory care and hospitalizations coded as epilepsy and (b) procedures and drugs specifically associated with the diagnosis or treatment of epilepsy. These methods may underestimate the cost of medical care for epilepsy. Two methods for estimating the medical care costs of epilepsy ("epilepsy-attributable cost method" and "case-control cost method") were compared.

METHODS

The study population was 655 individuals with an epilepsy diagnosis enrolled in a managed care plan in the southwestern United States. The epilepsy-attributable costs were determined by summing costs for inpatient and outpatient encounters coded as epilepsy, procedures for the diagnosis or treatment of epilepsy, and drugs used to treat epilepsy. The case-control method determined costs by calculating the difference in total costs between cases and 1,965 age- and gender-matched controls.

RESULTS

The case-control epilepsy costs were $2,923 per case compared with epilepsy-attributable costs of $1,335 per case. The case-control method found statistically significant differences in costs between cases and controls for inpatient care, prescription drugs, and 8 of 11 categories of outpatient care. The largest contributors to the discrepancy between estimates were inpatient care, emergency department care, laboratory tests, and "other specialist" care.

CONCLUSIONS

Epilepsy-attributable costs accounted for only 46% of the total difference in costs between epilepsy cases and controls. Persons with epilepsy use more medical services than controls, but a substantial portion of this care is not coded to epilepsy.

Utilization in COPD: patient characteristics and diagnostic evaluation

STUDY OBJECTIVES

Information on current practices of COPD diagnosis and treatment is needed to identify opportunities for improving care. This study describes the clinical characteristics and diagnostic evaluations of COPD patients in a health maintenance organization (HMO) and a university-affiliated county medical center (UMC).

DESIGN

Cross-sectional survey performed in a 174,484-member regional HMO and in The University of New Mexico Hospitals and Clinics (UNMH).

PATIENTS

Two hundred COPD patients from each system randomly selected from administrative databases based on discharge diagnoses.

RESULTS

COPD patients in the UMC, compared to those in the HMO, were younger (mean age, 59.3 vs 66.9 years, respectively), were more likely to be using home oxygen (33% vs 20%, respectively), and had fewer chronic medical conditions (mean number of conditions, 3.1 vs 3.7, respectively) (p < 0.01 for all differences). Approximately half of the COPD patients in both groups continued to smoke cigarettes during the study year. Only 38% of patients in the HMO and 42% in the UNMH system had spirometry results documented in their medical records.

CONCLUSIONS

The demographic and clinical characteristics of the COPD patients in these two health-care systems were very different, but smoking status and utilization of diagnostic tests were similar. The diagnosis of COPD in most patients was based only on a history of chronic respiratory symptoms and smoking; spirometry often was not used to confirm the diagnosis. An increased emphasis on smoking cessation and more effective utilization of spirometry are needed to improve the management of COPD in these health-care systems.

NeuroD/BETA2 gene variability and diabetes: no associations to late-onset type 2 diabetes but an A45 allele may represent a susceptibility marker for type 1 diabetes among Danes. Danish Study Group of Diabetes in Childhood, and the Danish IDDM Epidemiology and Genetics Group

Mutations in the NeuroD/BETA2 gene have been shown to associate with type 2 diabetes. In the present study, we examined mutations in the NeuroD/BETA2 gene for association with either type 1 or 2 diabetes. Three variants were identified in patients with type 2 diabetes: Ala45Thr (allelic frequency 0.36, 95% CI 0.31-0.41), Pro197His (0.01), and Ser259Ser (0.01). Ala45Thr and Pro197His were not associated with type 2 diabetes, but the transmission disequilibrium test showed unequal transmission of the A45 allele to offspring with type 1 diabetes (chi2 = 5.90, P < 0.02, odds ratio 1.55, 95% CI 0.91-2.63). This association could not be explained by linkage disequilibrium between the Ala45 allele and IDDM7 (D2S152), which is also located on chromosome 2q32. When tested in vitro, the biological activity of Thr45 (117+/-36% vs. Ala45) and His197 (90+/-28% vs. Pro197) on the regulation of the human insulin gene promoter appeared normal. In conclusion, mutations in the NeuroD/BETA2 gene are not a common cause of late-onset type 2 diabetes among Danes. However, in the type 1 diabetic Danish population, the Ala45Thr variant of NeuroD/BETA2 may represent a susceptibility marker independent of IDDM7 on chromosome 2q32.

Pax4 represses pancreatic glucagon gene expression

The paired box and homeodomain containing transcription factors Pax4 and Pax6 are known to be essential for development of the pancreatic endocrine cells. In this report we demonstrate that stable expression of Pax4 in a rat glucagon-producing cell line inhibits the endogenously expressed glucagon gene completely. Furthermore, Pax4 represses Pax6 independent transcription of the insulin promoter, suggesting that Pax4 can actively repress transcription in addition to acting by competition with the transcriptional activator Pax6.

Missense mutations in the human insulin promoter factor-1 gene and their relation to maturity-onset diabetes of the young and late-onset type 2 diabetes mellitus in caucasians

Increasing evidence suggests that defects in genes encoding transcription factors that are expressed in the pancreatic beta-cells may be important contributors to the genetic basis of type 2 diabetes mellitus. Maturity-onset diabetes of the young (MODY) now exists in five subtypes (MODY1-5), four of which are caused by mutations in transcription factors hepatocyte nuclear factor-4alpha (HNF-4alpha), HNF-1alpha, insulin promoter factor-1 (IPF-1), and HNF-1beta (MODY1, -3, -4, and -5). Recent evidence from the British population even suggested that IPF-1 may be a predisposing gene for type 2 diabetes. Thus, highlighting the potential role of this transcription factor in the genetic basis of Danish and Italian MODY as well as in Danish patients with late-onset type 2 diabetes mellitus, we have examined the human IPF-1 gene for mutations by single strand conformation polymorphism and heteroduplex analysis in 200 Danish patients with late-onset type 2 diabetes and in 44 Danish and Italian MODY patients. In the patients with late-onset type 2 diabetes we identified a noncoding G insertion/deletion polymorphism at nucleotide -108, a silent G54G, and a rare missense D76N variant. Moreover, a Danish MODY patient was carrier of an A140T variant. Neither the D76N nor the A140T segregated with diabetes, and their transcriptional activation of the human insulin promoter expressed in vitro was indistinguishable from that of the wild type (115 +/- 21% and 84 +/- 12% vs. 100%). We conclude that variants in IPF-1 are not a common cause of MODY or late-onset type 2 diabetes in the Caucasian population, and that in terms of insulin transcription both the N76 and the T140 mutations are likely to represent functionally normal IPF-1 variants with no direct role in the pathogenesis of MODY or late-onset type 2 diabetes mellitus.

Pax6 and Pdx1 form a functional complex on the rat somatostatin gene upstream enhancer

The somatostatin upstream enhancer (SMS-UE) is a highly complex enhancer element. The distal A-element contains overlapping Pdx1 and Pbx binding sites. However, a point mutation in the A-element that abolishes both Pdxl and Pbx binding does not impair promoter activity. In contrast, a point mutation that selectively eliminates Pdx1 binding to a proximal B-element reduces the promoter activity. The B-element completely overlaps with a Pax6 binding site, the C-element. A point mutation in the C-element demonstrates that Pax6 binding is essential for promoter activity. Interestingly, a block mutation in the A-element reduces both Pax6 binding and promoter activity. In heterologous cells, Pdx1 potentiated Pax6 mediated activation of a somatostatin reporter. We conclude that the beta/delta-cell-specific activity of the SMS-UE is achieved through simultaneous binding of Pdx1 and Pax6 to the B- and C-elements, respectively. Furthermore, the A-element appears to stabilise Pax6 binding.

Pax6 and Cdx2/3 form a functional complex on the rat glucagon gene promoter G1-element

Alpha-cell specific transcription of the glucagon gene is mainly conferred by the glucagon promoter G1-element, while additional elements G2, G3, and G4 have broad islet cell specificity. Transcription of the glucagon gene has been shown to be stimulated by Pax6 through binding to the glucagon gene promoter G3-element. In this report, we show that Pax6 additionally binds the glucagon gene promoter G1-element and forms a transcriptionally active complex with another homeodomain protein, Cdx2/3. Two distinct mutations in the G1-element, that both reduce promoter activity by 85-90%, is shown to eliminate binding of either Pax6 or Cdx2/3. Additionally, Pax6 enhanced Cdx2/3 mediated activation of a glucagon reporter in heterologous cells. We discuss how Pax6 may contribute to cell-type specific transcription in the pancreatic islets by complex formation with different transcription factors.

Glucose stimulates the activation domain potential of the PDX-1 homeodomain transcription factor

Glucose-stimulated expression of the insulin gene in beta cells is mediated by the PDX-1 transcription factor. In this report, we show that stimulation results from effects on activation and DNA-binding potential. Thus, glucose specifically stimulated expression in MIN6 beta cells from chimeras of PDX-1 and the GAL4 DNA-binding domain which spanned the N-terminal PDX-1 activation domain located between amino acids 1 to 79. GAL4:PDX activity was induced over physiological glucose concentrations and was also regulated by effectors of this response. The level of endogenous PDX-1 binding and phosphorylation were also induced under these conditions. We discuss how changes in PDX-1 phosphorylation may influence activity in glucose-treated beta cells.

Mammography screening and breast cancer tumor size in female members of a managed care organization

A study of temporal trends in mammography screening and changes in stage of disease at diagnosis was conducted among Hispanic and non-Hispanic white female members of the Lovelace Health Plan, Flexcare Plan, and Lovelace Senior Plan/Senior Options (LHP), a managed care organization. Two-year screening rates for female members ages 50-74 years were calculated for 1989-1996. From 1989-1996, mammography screening rates for non-Hispanic white female members increased from 65.5 to 71.6%, although this was not a statistically significant increase. Screening rates for Hispanic female members also increased from 50.6 to 62.7%, but they were significantly lower than for non-Hispanic white women. All breast cancers occurring among LHP female members ages 40-74 years were also identified for this same time period. A logistic regression model adjusting for age, year of diagnosis, ethnicity, and duration of enrollment prior to diagnosis found that statistically significant predictors of more advanced stage of disease at diagnosis included young age, diagnosis after 1991 for non-Hispanic white women, and diagnosis prior to 1992 for Hispanic women. Longer duration of enrollment prior to diagnosis was predictive of lower stage of disease, but the odds ratio was not statistically significant. For the time period 1992-1996, Hispanic women with breast cancer were more than twice as likely to have advanced stage of breast cancer compared with non-Hispanic white women (odds ratio, 2.12).

Transcription factors contributing to the pancreatic beta-cell phenotype

Insulin promoter factor-1 (IPF1) (renamed to pancreatic-duodenal homeobox factor-1, PDX1) was originally cloned and characterized as an islet beta-cell specific insulin gene transcription factor (1) and later shown to be essential for the formation of the mature pancreas (2, 3). In the adult normal pancreas PDX1 is almost exclusively expressed in the beta-cell compartment and generally absent from the alpha-cell while it is widely expressed in the pancreatic epithelium during development. Using pluripotent rat islet tumor cultures and derived insulinomas and glucagonomas we have analyzed differential expression of a large number of genes including the transcription factors PDX1, Nkx6.1, Pax6, and NeuroD. While NeuroD and Pax6 expression was detectable among all phenotypes, PDX1 was expressed in the pluripotent culture and maintained in the insulinoma, while Nkx6.1 was selectively co-induced with insulin during insulinoma formation. Both factors were not detectable in the glucagonoma. Nkx6.1 proved to have a highly beta-cell restricted expression in the adult rat. Forced expression of recombinant PDX1 in the glucagonoma resulted in efficient transcriptional activation of the endogenous insulin and IAPP genes, but did not affect glucagon gene activity. In this hybrid alpha/beta-cell phenotype the endogenous Nkx6.1 gene remained silent. We conclude that PDX1 in synergy with NeuroD specifies part of the beta-cell phenotype including transcriptional activation of insulin and IAPP genes, but that other factors such as Nkx6.1 and Pax6 are required for additional features of the fully mature beta-cell phenotype.

Pancreatic development and maturation of the islet B cell. Studies of pluripotent islet cultures

Pancreas organogenesis is a highly regulated process, in which two anlage evaginate from the primitive gut. They later fuse, and, under the influence of the surrounding mesenchyme, the mature organ develops, being mainly composed of ductal, exocrine and endocrine compartments. Early buds are characterized by a branching morphogenesis of the ductal epithelium from which endocrine and exocrine precursor cells bud to eventually form the two other compartments. The three compartments are thought to be of common endodermal origin; in contrast to earlier hypotheses, which suggested that the endocrine compartment was of neuroectodermal origin. It is thus generally believed that the pancreatic endocrine-lineage possesses the ability to mature along a differentiation pathway that shares many characteristics with those of neuronal differentiation. During recent years, studies of insulin-gene regulation and, in particular, the tissue-specific transcriptional control of insulin-gene activity have provided information on pancreas development in general. The present review summarizes these findings, with a special focus on our own studies on pluripotent endocrine cultures of rat pancreas.

Strategic disaster preparedness and response: implications for military medicine under joint command

With the end of the Cold War, renewed emphasis has been placed on humanitarian assistance such as disaster relief, refugee management, and humanitarian intervention during conflicts by the military forces of all nations. The role of the military in humanitarian assistance has been the subject of much recent debate, as the ability of the United States to mount an effective emergency response is linked to our nation's strategic policy and planning. This article describes and broadens the understanding of the evolving concepts of strategic disaster management and the role of Joint Military Commands in providing disaster relief. Examples of strategic humanitarian relief operations are discussed.

The homeodomain protein IPF-1/STF-1 is expressed in a subset of islet cells and promotes rat insulin 1 gene expression dependent on an intact E1 helix-loop-helix factor binding site

The mouse homeodomain protein insulin promoter factor-1 (IPF-1) and the rat homologue somatostatin transactivating factor-1 (STF-1) are involved in early pancreatic development and have been implicated in the cell-specific regulation of insulin- and somatostatin-gene expression in mature islet beta- and delta-cells. The cell specificity of IPF-1/STF-1 expression in mature islets is, however, still unclear. Using antisera against recombinant IPF-1 and STF-1 in combination with antisera against islet hormones we find that all beta-cells in monolayers of newborn rat islet cells express STF-1, as do a fraction of the delta-cells. In adult rat and mouse pancreas we find a similar distribution. IPF-1/STF-1 expression was not detected in glucagon-producing alpha-cells. In islet cell tumour models we found that a glucagon/islet amyloid polypeptide (IAPP)-producing pluripotent rat islet cell line (NHI-6F-GLU) expresses STF-1 in all cells prior to insulin gene activation induced by in vivo culture. In contrast, a mouse alpha-cell line (alpha TC1) exclusively expressed IPF-1 in a small subset of insulin-producing cells while an insulin-negative subclone (alpha TC1.9) was negative for IPF-1. In transfection experiments using alpha TC1.9 cells STF-1 activated a rat insulin 1 reporter gene dependent not only on both STF-1-binding sites, but also on the E1-binding site for the helix-loop-helix factor IEF-1. However, the endogenous mouse insulin genes remained inactive in these cells. These results suggest that the insulin promoter acquires its very high, yet cell-specific, activity at least partly through the action of IPF-1/STF-1. This action is dependent on helix-loop-helix factors bound to the E1 element.

Transcriptional regulation of the human insulin gene is dependent on the homeodomain protein STF1/IPF1 acting through the CT boxes

Insulin gene transcription is a unique feature of the pancreatic beta cells and is increased in response to glucose. The recent cloning of insulin promoter factor 1 (IPF1) and somatostatin transcription factor 1 (STF1) unexpectedly revealed that these are mouse and rat homologues of the same protein mediating transactivation through binding of CT box-like elements in rat insulin 1 and somatostatin promoter/enhancer regions, respectively. By using oligonucleotides representing each of the three CT boxes of the human insulin (HI) gene enhancer and nuclear extracts from the mouse islet tumor cell lines beta TC3 and alpha TC1, we have identified a beta-cell-specific binding activity as reported for IPF1, which has maximal affinity toward the CT2 box. However, in pluripotent, HI-transfected rat islet tumor cells, NHI-6F, this binding activity is present prior to induction of (human) insulin gene transcription. Its migration is identical to that of in vitro translated STF1 in electrophoretic mobility-shift assays; it is specifically recognized by anti-STF1 antibodies and has an apparent molecular mass of 46 kDa. Mutation of the CT2 box decreases transcriptional activity of a HI reporter plasmid by approximately 65% in beta TC3 cells and blocks the glucose response in isolated newborn rat islet cells. Furthermore, cotransfection with STF1 cDNA into the glucagon-producing alpha TC1 cells increases the activity of the HI enhancer 4- to 5-fold, suggesting that STF1/IPF1 can confer on alpha TC1 cells the ability to transcribe the HI gene. We conclude that STF1/IPF1 is a necessary but not sufficient key regulator of insulin gene activity, possibly also involved in glucose-regulated transcription.

Human insulin gene enhancer-binding proteins in pancreatic alpha and beta cell lines

Electrophoretic mobility shift assays were performed using oligonucleotides corresponding to known protein binding sites within the human insulin gene enhancer and nuclear extracts from mouse pancreatic alpha and beta cell lines. The results demonstrate that a previously described factor, IUF-1, binds to three sites at -82 (the CT1 box), -215 (the CT2 box), and -319 (the CT3 box) in the human insulin gene enhancer. IUF-1 was present only in beta but not in alpha cells, while all other DNA-binding proteins were present in both cell lines. IUF-1 may therefore be an important determinant of insulin gene beta cell-specific expression.