OP0154-HPR EFFECT OF NURSE-LED-CARE ON PATIENT OUTCOMES IN RHEUMATOID ARTHRITIS IN GERMANY: A MULTICENTRE RANDOMISED CONTROLLED TRIAL

Background:

Inflammatory rheumatic disorders are very complex and require high medical resources. However, there is a shortage of care for these patients, which results in suboptimal reach of therapy objectives. Nevertheless, these very objectives need to be pursued quickly to prevent permanent joint damage. In order to ensure adequate care, multidisciplinary teams which include clinical nurse specialists are required. These clinical nurse specialists play an important role in improving standard-of-care in addition to the rheumatologist. The current standard of care ensures that essential medical provision remains intact, however, psychological, social, rehabilitative and educational needs are often skipped due to time constraints. While studies from e.g. the UK and Denmark have already supported the non-inferiority of nurse-led care (NLC)1, no such studies have yet been published in Germany.

Objectives:

To demonstrate the non-inferiority of NLC to the current standard-of-care, rheumatologist-led care (RLC), for patients with seropositive rheumatoid arthritis (RA) with induction, escalation or change of therapy regarding disease activity as well as different patient reported outcomes (PROs).

Methods:

This trial was conducted as a prospective multi-centered RCT with a non-inferiority design over the course of 12 months. Based on power calculations, 236 adults with RA were included in the study and randomized to either NLC or RLC. The primary outcome measure is disease activity (DAS28), assessed at baseline (T0), 6 weeks (T1), 3,6, 9, and 12 months (T3, T6, T9, T12). Secondary measures are health related quality of life (RAID), functionality (FFbH) and depression (PHQ9).

Results:

There are no significant differences between intervention group (IG) (n=117) and control group (CG) (n=119) at baseline. The mean age of the IG is 58.80 years (SD=12.09) and of the CG 58.34 years (SD=11.72). 72.4% of the IG and 78.1% of the CG are female. The mean duration of symptoms was 147 months (SD=144.63) for the IG and 116 months (108.89) for the CG. The mean DAS28 for the IG is 4.36 (SD=1.24) and 4.51 (SD=1.24) for the CG.

A mixed one-way repeated measures ANOVA showed that the DAS28 improves significantly over time, Huyn-FeldtF(4.42, 751.72) = 105.701,p< .001, partialη2= 0.383, but the interaction of the DAS28 and the randomization is not significant, Huyn-FeldtF(4.42, 751.72) = 1.464,p= 0.260, partialη2= 0.009. No main effect for randomization was found, meaning that the IG and CG did not differ significantly,F(1, 170) = 1.005,p= 0.317, partialη2= 0.006.

The Mann-Whitney-Test showed that the change of the secondary outcomes does not depend on the randomization FFbHU= 4978.50,Z= -.755,p=.450. RAIDU= 5121.00,Z= -.539,p=.590. PHQ9U= 4800.50,Z= -1.281,p=.200. The secondary outcomes improve significantly over time, as shown by a Wilcoxon Signed Rank test for the FFbHZ= -5.589,p< .001, the RAIdZ= -9.884,p< .001 and the PHQ9Z= -7.960,p< .001.

Conclusion:

The results support the non-inferiority of NLC in the management of RA regarding the primary and secondary outcome measures and provide first evidence that NLC could improve care and help carry the doctors’ workflow.

Figure 1.Figure 2.

References:

[1]de Thurah A, Esbensen BA, Roelsgaard IK, et al. Efficacy of embedded nurse-led versus conventional physician-led follow-up in rheumatoid arthritis: a systematic review and meta-analysis. RMD Open 2017;3:e000481.

Disclosure of Interests:

Juliana R Hoeper: None declared, Georg Gauler Consultant of: Abbvie, Lilly, MSD, Speakers bureau: Abbvie, Celgene, Novartis, Sanofi,, Dirk Meyer-Olson Grant/research support from: Novartis, Sandoz Hexal, Consultant of: Abbvie, Amgen, Bristol Myers Squibb, Chugai, Lilly, Mylan, Novartis, Sandoz Hexal, Sanofi, Speakers bureau: Abbvie, Bristol Myers Squibb, Chugai, Lilly, Novartis, Pfizer, Sandoz Hexal, Sanofi, Karin Rockwitz Consultant of: Janssen Cilag, Speakers bureau: Janssen Cilag, Patricia Steffens-Korbanka Consultant of: Abbvie, Chugai, Novartis, Sanofi, Mylan, Lilly, Speakers bureau: Abbvie, Chugai, Novartis, Sanofi, Lilly, Carsten Stille: None declared, Jochen Walter Consultant of: Pfizer, Speakers bureau: AbbVie, Frauenhofer Institut, Gilead, Janssen-Cilag, Medac, Novartis, Pfizer, Martin Welcker Grant/research support from: Abbvie, Novartis, UCB, Hexal, BMS, Lilly, Roche, Celgene, Sanofi, Consultant of: Abbvie, Actelion, Aescu, Amgen, Celgene, Hexal, Janssen, Medac, Novartis, Pfizer, Sanofi, UCB, Speakers bureau: Abbvie, Aescu, Amgen, Biogen, Berlin Chemie, Celgene, GSK, Hexal, Mylan, Novartis, Pfizer, UCB, Joerg Wendler Consultant of: Janssen, AbbVie, Sanofi, Speakers bureau: Roche, Chugai, Janssen, AbbVie, Novartis, Jan Zeidler: None declared, Kirsten Hoeper Consultant of: AbbVie, Celgene,, Speakers bureau: Abbvie, Chugai, Novartis, Lilly, Celgene, Sandoz Hexal

AB1298-HPR RHEUMA-VOR: A PROOF-OF-CONCEPT NETWORK STUDY FOR THE IMPROVEMENT OF RHEUMATOLOGICAL HEALTH CARE THROUGH COORDINATED COOPERATION

Background:

Rheumatoid arthritis (RA), psoriasis arthritis (PsA) and spondyloarthritis (SpA) are the most common chronic inflammatory rheumatic diseases. For all three diseases, the so-called “window of opportunity” [1,2,4] has been identified as the decisive factor affecting the outcome.

Objectives:

The aim of the prospective study is to improve the early diagnosis of RA, PsA and SpA and thus positively impact the quality of care for patients with the support of coordinating centers.

Methods:

Primary care providers are given access to screening questionnaires to document potential early cases of RA, PsA, and SpA, based on characteristic symptoms. These are evaluated by multidisciplinary teams at the regional coordinating centers. If they fulfill the criteria for referral, patients get an appointment at a cooperating rheumatology specialist within weeks. If a rheumatic disease is diagnosed, physicians and patients receive questionnaires about sociodemographic, physilogical and psychological parameters.

In order to increase the quality of referrals, a 15-minute rheumatological consultation at the ACURA Rheumatology Center was implemented for all patients from Rhineland-Palatinate whose suspected diagnosis was confirmed by the coordination centre. In course of this, the Rheuma-VOR Screening-App will also be developed and optimized. The cooperating partners and additional information are already published [5].

Results:

Preliminary data (31 Dec 2019) are presented. In Rhineland-Palatinate, Saarland and Lower Saxony, 4942 suspected diagnoses of 1526 different referring physicians have now been reported. A total of 2578 patients were referred by the three coordination centres to one of the 49 participating rheumatological specialists. 1004 patients were diagnosed with one of the three diseases. About 306 patients have already taken the follow-up appointment after one year.

In course of a screening consultation 736 patients have been screened to date. The patients have to wait in average about 42 days from the suspected diagnosis to the rejected or confirmed rheumatological diagnosis.

Conclusion:

Although the average waiting time for all three diseases is currently almost twice as long as the 23.9 days in the Rhineland-Palatinate predecessor project ADAPTHERA which just focuses on RA, the current results are very positive compared to the national average [3]. The aim is to further increase the screening quality and screening numbers, especially in the 1-year follow-up.

Current data will be presented at the conference.

References:

[1]Boehncke WH, Menter A (2013) Burden of disease: psoriasis and psoriatic arthritis. Am J Clin Dermatol 14:377-388

[2]Claudepierre P (2014) Spondyloarthritis: a window of opportunity? Joint Bone Spine 81:197-199

[3]Lauter A, Triantafyllias K, Leiß R et al. (2019) ADAPTHERA—Statewide cross-sectoral care network for patients with early rheumatoid arthritis shows sustained remission in standard care. ZRheumatol. 78 (7): 660–669

[4]O’dell JR (2002) Treating rheumatoid arthritis early: a window of opportunity? Arthritis Rheum 46:283-285

[5]Schwarting A (2018) From ADAPTHERA to Rheuma-VOR: Concept of Coordinated Cooperation to Improve the Quality of Rheumatology Care Akt Rheumatol 43 (05): 406-409

Acknowledgments:

The authors thank all partners and participants of Rheuma-VOR

Disclosure of Interests:

Matthias Dreher: None declared, Reinhold E. Schmidt: None declared, Torsten Witte: None declared, Gunter Assmann: None declared, Kirsten Hoeper Consultant of: AbbVie, Celgene,, Speakers bureau: Abbvie, Chugai, Novartis, Lilly, Celgene, Sandoz Hexal, Konstantinos Triantafyllias: None declared, Jan Zeidler: None declared, Harald Binder: None declared, Andreas Schwarting: None declared

P3523Cardiac contractility modulation provides improved ventilatory efficiency and reduces oscillatory breathing pattern

Introduction

Cardiac Contractility Modulation (CCM) is a treatment for patients with heart failure with reduced ejection fraction (HFrEF) providing improved myocardial molecular and biochemical characteristics and thus improved exercise tolerance and quality of life by application of electrical signals during the absolute refractory period.

Cardiopulmonary exercise testing is an integrative method to assess exercise tolerance in heart failure patients providing insights in circulatory, respiratory and metabolic reactions during exercise. The VE/VCO2-Slope (minute ventilation/carbon dioxide production) and an oscillatory breathing pattern have widely been demonstrated to have strong prognostic value for patients with chronic heart failure.

Methods

Between February 2017 and January 2019 15 patients (mean age 64.4±7.9 years, NYHA 2.93±0.58) with standard indication for CCM-therapy have been enrolled in a single center in Germany. Prior to implantation of the Optimizer Smart System, symptom-limited cardiopulmonary exercise testing was performed using a bicycle ramp protocol (25W+10W/min). The Follow-up was conducted 6 weeks post implantation.

The control group consisted of 45 patients (mean age 64.8±7.9 years, NYHA 2.2±0.72) with stable systolic heart failure and reduced ejection fraction. Statistical Analysis was performed by paired and unpaired t tests.

Results

6 weeks after CCM-implantation the VE/VCO2-Slope showed a significant decrease (39.6±11.1 vs. 36.6±8.9, p<0.05) showing changes in ventilatory efficiency whereas the control-group showed stable measurements with even an increasing tendency (33.6±7.4 vs. 34.2±7.4, p=0.43). The absolute change of the VE/VCO2-Slope between the CCM-group and control-group highlights the improvement after the intervention (−2.99±5.07 vs. 0.63±4.79, p<0.05). The number of patients presenting an oscillatory breathing pattern markedly decreased with CCM-therapy (11 of 15 vs. 6 of 15, p<0.05), whereas even one additional patient of the control group showed an oscillatory breathing pattern at follow up (15 of 45 vs. 16 of 45).

In contrast, subjects showed no significant changes in watt-measurements (72.67 W ± 19.2 W vs. 76.57 W ± 18.5 W) or maximal oxygen uptake (1034 ml/min ± 247 ml/min vs. 1104 ml/min ± 256 ml/min) compared to baseline. Similarly, the control-group showed stable measurements for external load (79.9 W ± 16.4 W vs. 77.1 W ± 17.5 W) and peak oxygen uptake (1097 ml/min ± 225 ml/min vs. 1116 ml/min ± 330 ml/min).

Conclusion

Cardiac Contractility Modulation provides improved ventilatory efficiency measures by VE/VCO2-slope and reduces oscillatory breathing pattern during exercise at follow up. As the low ventilatory efficiency observed in patients with heart failure constitutes an important predictor of cardiovascular mortality these results provide an interesting insight of therapeutic effects of Cardiac Contractility Modulation apart from VO2-measurements.

Needs and preferences of informal caregivers regarding outpatient care for the elderly: a systematic literature review

BACKGROUND

Informal caregivers are an essential pillar for ensuring and maintaining the outpatient care of the frail elderly. Due to demographic changes, including an increase in the number of people in need of care as well as changing social structures (full-time employment of women, increasing number of single households, etc.) these informal care structures are fraught by considerable challenges. To support and facilitate informal caregivers in their role of nursing, it is important to identify their preferences, needs, and thus create a preference-oriented system.

METHODS

A systematic review was conducted to identify preferences and needs regarding the organization of informal care. The database searches were performed by using EMBASE, Scopus and Dimdi.

RESULTS

A total of 44 studies were included in the present review. Studies from 17 different countries provide broad international perspectives. Besides the preferences for long-term care structure, the following four principal topics were identified: (1) informational needs; (2) support needs; (3) organizational needs, and (4) needs for societal recognition.

CONCLUSION

To meet the current challenges in the outpatient or home-based care of elders, it is essential to strengthen the role of informal caregivers. Therefore, it is necessary to adopt and further develop informal care structures according to the needs of informal caregivers. However, demographic, financial and cultural aspects of each country need to be considered as these may influence the preferences and needs of informal caregivers.

Surgery for Pediatric Ureteropelvic Junction Obstruction-Comparison of Outcomes in Relation to Surgical Technique and Operating Discipline in Germany

INTRODUCTION

 Surgery for ureteropelvic junction obstruction (UPJO) is performed by both pediatric surgeons (PS) and urologists (URO). The aim of this study was to analyze treatment modalities for UPJO and results in relation to the surgical technique and the operating discipline in Germany.

MATERIALS AND METHODS

 Data of patients aged 0 to 18 years were extracted from a major public health insurance (covering ∼5.7 million clients) during 2009 to 2016 and were analyzed for sociodemographic variables, surgical technique, and treating discipline. Logistic regression analysis was performed for the risk of a complication within the first postoperative year.

RESULTS

 A total of 229 children (31.0% female) were included. Laparoscopic pyeloplasty (LP) was performed in 58 (25.3%) patients (8.6 ± 6.4 years), and open pyeloplasty (OP) was applied in 171 (74.7%; 4.6 ± 5.9 years). LP was the dominant technique in females (p < 0.02); males preferentially underwent OP (p < 0.02). Length of hospital stay was 4.3 days (p = 0.0005) shorter in LP compared with that in OP, especially in children ≤ 2 years (6.7 days, p = 0.007). PS operated on 162 children (70.7%), and URO performed surgery on 67 patients (29.3%). The mean age of children operated by PS (3.5 ± 4.7 years) was significantly younger compared with that operated by URO (10.8 ± 6.5 years, p < 0.0001). Complication rates were independent of surgical technique or treating specialty.

CONCLUSION

 In Germany, UPJO was treated by LP in 25.3% of patients, which was associated with a shorter length of stay, especially in children ≤ 2 years. Complication rates were independent of the operating specialty and surgical technique. Therefore, LP should be further promoted for the treatment of UPJO in small children.

Guidelines versus reality: is coronary stent application in three-vessel disease standard or the exception?

The national guidelines for treatment of chronic coronary heart disease (CHD) recommend surgical coronary aortic bypass grafting (CABG) rather than percutaneous coronary intervention (PCI) for patients with a coronary three-vessel disease. The epidemiology of three-vessel CHD and data about the application of different revascularisation strategies raise suspicion of deviation from the guidelines in the treatment of those patients. Claims data containing records of almost 10 million patients of the largest German statutory health insurance fund (Techniker Krankenkasse) were utilised to measure adherence to the guidelines for treatment of groups of patients with one-, two-, and three-vessel CHD, respectively. The impact of age, sex, and comorbidity on each patient's revascularisation procedure was investigated as well. There was no significant difference in the rate of PCI between the groups. In conclusion, the hypothesis that patients with a coronary three-vessel disease are not always treated according to the recommendations of the national guidelines could not be disproved by this study. Finally, the results of this study suggest that the best revascularisation strategy for each patient with two- and three-vessel disease should be decided upon by an interdisciplinary discussion between both cardiologists and cardiac surgeons.

Early complications after esophageal atresia repair: analysis of a German health insurance database covering a population of 8 million

The treatment of esophageal atresia is not centralized in Germany. Therefore, high numbers of departments are involved. Data on the results of esophageal atresia repair from Germany are lacking. The aim of this study was to evaluate the early postoperative results after repair of esophageal atresia based on unbiased data of a German health insurance. We aimed to determine whether characteristics of the departments had an impact on outcome and compared the results from this study with the literature data from centers with a high caseload. Data of a German health insurance covering ∼10% of the population were analyzed. All patients who had undergone esophageal atresia repair from January 2007 to August 2012 were included. Follow-up data of 1 year postoperatively were analyzed. The potential impact of various characteristics of the treating surgical institutions was assessed. Results were compared with the latest international literature. Seventy-five patients with esophageal atresia underwent reconstructive surgery in 37 departments. The incidences of anastomotic leak (3%) and recurrent tracheoesophageal fistula (7%) were comparable with the literature (both 2-8%). Anastomotic stricture required dilatation in 57% of patients (mean 5.1 ± 5.6 dilatations) comparing unfavorably to most, but not all international reports. During 1-year follow-up, 93% of the patients were readmitted at least once (mean 3.9 ± 3.1 admissions). The incidence of complications did not correlate with any of the characteristics of the treating institutions such as academic affiliation, the number of consultants, beds, and preterm infants treated per year (all P > 0.05). Based on unbiased data, postoperative results after repair of esophageal atresia in Germany are comparable with recently published reports from international single centers. A correlation between the complication rate and characteristics of the treating institutions was not identified.

[Age- and Gender-specific Costs as Well as Drug Therapies of ADHD Patients]

Backround and Objectives: Attention deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed mental disorders in children and adolescents. The rate of persistence into adulthood varies up to 60% and shows the importance of the disease. Here we present age-stratified cost information on adult patients, as well as data on occupational therapy, medication and multimodal treatment. Furthermore, we also investigated retrospectively if methylphenidate was prescribed for adults already before its approval in 2011.

METHODS

Claims data of a major German insurance fund (Techniker Krankenkasse) was available. Inclusion criteria were patients with ADHD diagnosis, either hospitalized or treated on an outpatient basis in 2006, 2007 and 2008 and insured over this period. This enabled identifying this disease as chronic. The data were analyzed as part of a control group design (1:3). Cost differences were examined as also the odds ratios for the burden of comorbidities and use of atomoxetine and methylphenidate.

RESULTS

77.9% of the identified ADHD patients were male (mean age: 16.5 years ±11.1). The mean total costs of patient treatment were € 2,032 (±4,112). The odds ratio was highest for the indication developmental disorders of scholastic skills (15.4) and differed between the sexes (female: 24.0 vs. male: 14.2). Drug prescription was higher in male than in female patients (atomoxetine: 7.2 vs. 5.9% and methylphenidate 59.1 vs. 48.4%).

CONCLUSIONS

This study provides important insights into the importance of the adult ADHD collective. There were increasing resource consumption identified in adult ADHD patients. In addition, methylphenidate was used off-label for treating adults already before 2011 and its approval in 2011 provided increased certainty for physicians regarding prescription of this drug.

Cost of poor adherence to anti-hypertensive therapy in five European countries

The financial burden for EU health systems associated with cardiovascular disease (CV) has been estimated to be nearly €110 billion in 2006, corresponding to 10% of total healthcare expenditure across EU or a mean €223 annual cost per capita. The main purpose of this study is to estimate the costs related to hypertension and the economic impact of increasing adherence to anti-hypertensive therapy in five European countries (Italy, Germany, France, Spain and England). A probabilistic prevalence-based decision tree model was developed to estimate the direct costs of CV related to hypertension (CV defined as: stroke, heart attack, heart failure) in five European countries. Our model considered adherence to hypertension treatment as a main driver of blood pressure (BP) control (BP < 140/90 mmHg). Relative risk of CV, based on controlled or uncontrolled BP group, was estimated from the Framingham Heart Study and national review data. Prevalence and cost data were estimated from national literature reviews. A national payer (NP) perspective for 10 years was considered. Probabilistic sensitivity analysis was performed in order to evaluate uncertainty around the results (given as 95% confidence intervals). The model estimated a total of 8.6 million (1.4 in Italy, 3.3 in Germany, 1.2 in Spain, 1.8 in France and 0.9 in England) CV events related to hypertension over the 10-year time horizon. Increasing the adherence rate to anti-hypertensive therapy to 70% (baseline value is different for each country) would lead to 82,235 fewer CV events (24,058 in Italy, 7,870 in Germany, 18,870 in Spain, 24,855 in France and 6,553 in England). From the NP perspective, the direct cost associated with hypertension was estimated to be <euro>51.3 billion (8.1 in Italy, 17.1 in Germany, 12.2 in Spain, 8.8 in France and 5.0 in England). Increasing adherence to anti-hypertensive therapy to 70% would save a total of <euro>332 million (CI 95%: €319-346 million) from the NPs perspective. This study is the first attempt to estimate the economic impact of non-adherence amongst patients with diagnosed hypertension in Europe, using data from five European countries (Italy, France, Germany, Spain and England).

One-year disease-related health care costs of incident vertebral fractures in osteoporotic patients

SUMMARY

The study aims to estimate the direct disease-related costs of osteoporotic vertebral compression fractures (OVCF) in patients with newly diagnosed fracture in the first year after index in Germany. Analyses reveal that OVCFs are associated with significant costs. In light of high and increasing incidence, the results emphasize importance of research in this field.

INTRODUCTION

OVCF are among the most common fractures related to osteoporosis. They have been shown to be associated with excess mortality and meaningful healthcare costs. Costs calculations have illustrated the significant financial burden to society and national social security systems. However, this information is not available for Germany. Therefore, aim of the study was to estimate the direct disease-related costs of OVCF in patients with newly diagnosed fracture in the first year after index in Germany.

METHODS

Data were obtained from a claims dataset of a large German health insurance fund. Subjects ≥ 60 years with a new vertebral fracture between 2006 and 2010 were studied retrospectively compared to a matched paired OVCF-free patient group. All-cause and fracture-specific medical costs were calculated in the 1-year baseline and follow-up period. Generalized linear model (GLM) was estimated for total follow-up healthcare cost.

RESULTS

A total of 2,277 pairs of matched OVCF and OVCF-free patients were included in the analysis. Baseline costs were higher in the OVCF group. Mean unadjusted all-cause healthcare cost difference in the four quarters following the index date between OVCF and OVCF-free patients was 8,200 <euro> (p < 0.001). Of the difference, almost two third was attributable to inpatient services and one quarter to prescription drug costs. The GLM procedure revealed that OVCF-related costs in the first year after the index date add up to 6,490 <euro> (p < 0.001; CI 5,809 <euro>-6,731 <euro>).

CONCLUSIONS

Despite limitations of this study, our results are consistent with other research and demonstrate that OVCFs are associated with significant costs. The results underline the importance of medical interventions that can help to prevent fractures and treatments, which are cost-effective and can prevent recurrent fractures.

[Therapy of rheumatoid arthritis with methotrexate. Claims data analysis of treatment patterns]

Methotrexate (MTX) is the most important disease-modifying antirheumatic drug (DMARD) and is recommended by national and international guidelines as the first choice for treatment of rheumatoid arthritis (RA). Recent studies reporting prescription data of MTX captured only patients who were treated by rheumatologists. Therefore, the aim of the present study was to analyse several aspects of the prescription of MTX based on claims data. Outpatient and inpatient diagnoses as well as prescription data was available for 9579 RA patients for the years 2005-2008. Of the patients 45% were treated exclusively with parenteral MTX, 8% were treated exclusively with oral MTX and 48% switched between both forms of application. The average weekly dosage presribed in 70% of the patients was between 10 and 25 mg. The most common DMARD combination was MTX plus leflunomide with 16%. In 16% RA patients were treated with a combination of MTX and TNF-α inhibitors. Glucocorticoids were prescribed temporarily in 81% together with MTX and supplementation with folic acid was given only in 65%. The results of this study provide important insights into the drug supply of MTX to RA patients in the German statutory health care sector. In particular, the high frequency of prescriptions of parenteral MTX and the inadequate prescription of folic acid are different from the recently published multinational recommendations of the 3E initiative for the use of MTX.

Fluorescent tricyclic analogues of acyclovir and ganciclovir. A structure-antiviral activity study

Of a series of new guanine base modified tricyclic analogues of acyclovir (ACV, 1) and ganciclovir (GCV, 2), derivatives of the 3,9-dihydro-9-oxo-5H-imidazo[1,2-a]purine system, evaluated for activity against herpes simplex virus type 1 and 2, several fluorescent analogues, 6-(4-MeOPh)-TACV (8), 7-Me-6-Ph-TACV (17), 6-(4-MeOPh)-TGCV (27), and 7-Me-6-Ph-TGCV (28), were obtained that showed similar potency and selectivity as the parent compounds. The activity was found to be strongly dependent on the nature and steric demands of the substituents in the 6 and/or 7 position.

Biosynthesis of 2-methyl-3-buten-2-ol emitted from needles of Pinus ponderosa via the non-mevalonate DOXP/MEP pathway of isoprenoid formation

The volatile hemiterpene 2-methyl-3-buten-2-ol (MBO) is emitted from the needles of several pine species from the Western United States and contributes to ozone formation in the atmosphere. It is synthesised enzymatically from dimethylallyl diphosphate (DMAPP). We show here that needles of Pinus ponderosa Laws. incorporated [1-2H1]-1-deoxy-D-xylulose (d-DOX) into the emitted MBO, but not D,L-[2-13C]mevalonic acid lactone. Furthermore, MBO emission was inhibited by fosmidomycin, a specific inhibitor of the second enzyme of the mevalonate-independent pathway of isopentenyl diphosphate and DMAPP formation, i.e. the 1-deoxy-D-xylulose 5-phosphate/2-C-methyl-D-erythritol 4-phosphate (DOXP/MEP) pathway. We thus prove that MBO emitted from needles of P. ponderosa is primarily formed via the DOXP/MEP pathway.

The non-mevalonate isoprenoid biosynthesis of plants as a test system for drugs against malaria and pathogenic bacteria

Two plant test systems are presented in the search for new inhibitors of the non-mevalonate isoprenoid pathway. A derivative of clomazone appears to be an inhibitor of the deoxyxylulose 5-phosphate/methylerythritol 4-phosphate (DOXP/MEP) pathway of isoprenoid formation.

Properties and inhibition of the first two enzymes of the non-mevalonate pathway of isoprenoid biosynthesis

Enzymes of the 1-deoxy-D-xylulose 5-phosphate/2-C-methylerythritol 4-phosphate (DOXP/MEP) pathway are targets for new herbicides and antibacterial drugs. Until now, no inhibitors for the DOXP synthase have been known of. We show that one of the breakdown products of the herbicide clomazone affects the DOXP synthase. One inhibitor of the non-mevalonate pathway, fosmidomycin, blocks the DOXP reductoisomerase (DXR) of plants and bacteria. The I(50) values of plants are, however, higher than those found for the DXR of Escherichia coli. The DXR of plants, isolated from barley seedlings, shows a pH optimum of 8.1, which is typical for enzymes active in the chloroplast stroma.

Substituent--directed aralkylation and alkylation reactions of the tricyclic analogues of acyclovir and guanosine

Aryl or tert-butyl substituent in the 6 position of 3,9-dihydro-3-[(2-hydroxyethoxy)methyl]-9-oxo-6-R-5H-imidazo[1,2-a]purine (6-R-TACV) 1 partly directs aralkylation reactions into unusual positions: N-4 to give 3 and C-7 to give N-5,7-disubstituted or N-4,7-disubstituted derivatives. In the case of alkylation the effect is limited to aryl substituent and position N-4. Replacement of acyclic moiety of 1 with a ribosyl one like in 7 prevents N-4 substitution. Cleavage of the third ring of 3b to give 3-benzylacyclovir 10 is an example of a new short route to 3-aralkyl-9-substituted guanines.

The non-mevalonate isoprenoid biosynthesis of plants as a test system for new herbicides and drugs against pathogenic bacteria and the malaria parasite

Higher plants and several photosynthetic algae contain the plastidic 1-deoxy-D-xylulose 5-phosphate/2-C-methyl-D-erythritol 4-phosphate pathway (DOXP/MEP pathway) for isoprenoid biosynthesis. The first four enzymes and their genes are known of this novel pathway. All of the ca. 10 enzymes of this isoprenoid pathway are potential targets for new classes of herbicides. Since the DOXP/MEP pathway also occurs in several pathogenic bacteria, such as Mycobacterium tuberculosis, and in the malaria parasite Plasmodium falciparum, all inhibitors and potential herbicides of the DOXP/MEP pathway in plants are also potential drugs against pathogenic bacteria and the malaria parasite. Plants with their easily to handle DOXP/MEP-pathway are thus very suitable test-systems also for new drugs against pathogenic bacteria and the malaria parasite as no particular security measures are required. In fact, the antibiotic herbicide fosmidomycin specifically inhibited not only the DOXP reductoisomerase in plants, but also that in bacteria and in the parasite P. falciparum, and cures malaria-infected mice. This is the first successful application of a herbicide of the novel isoprenoid pathway as a possible drug against malaria.

Inhibitors of the nonmevalonate pathway of isoprenoid biosynthesis as antimalarial drugs

A mevalonate-independent pathway of isoprenoid biosynthesis present in Plasmodium falciparum was shown to represent an effective target for chemotherapy of malaria. This pathway includes 1-deoxy-D-xylulose 5-phosphate (DOXP) as a key metabolite. The presence of two genes encoding the enzymes DOXP synthase and DOXP reductoisomerase suggests that isoprenoid biosynthesis in P. falciparum depends on the DOXP pathway. This pathway is probably located in the apicoplast. The recombinant P. falciparum DOXP reductoisomerase was inhibited by fosmidomycin and its derivative, FR-900098. Both drugs suppressed the in vitro growth of multidrug-resistant P. falciparum strains. After therapy with these drugs, mice infected with the rodent malaria parasite P. vinckei were cured.

Cloning and heterologous expression of a cDNA encoding 1-deoxy-D-xylulose-5-phosphate reductoisomerase of Arabidopsis thaliana

Various plant isoprenoids are synthesized via the non-mevalonate pathway of isopentenyl diphosphate formation. In this pathway, 1-deoxy-D-xylulose 5-phosphate (DOXP), the first intermediate, is transformed to 2-C-methyl-D-erythritol 4-phosphate (MEP) by an enzyme which was recently cloned from Escherichia coli. In order to find a plant homologue of this 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) we cloned a cDNA fragment from Arabidopsis thaliana which has high homology to the E. coli DXR. By expression of this fragment in E. coli we could demonstrate that it encodes a protein which transforms DOXP to MEP. The antibiotic fosmidomycin specifically inhibits this DXR enzyme activity.

Incorporation of 1-deoxy-D-xylulose into isoprene and phytol by higher plants and algae

In further substantiating the novel mevalonate-independent pathway for isoprenoid biosynthesis, which generates isopentenyl diphosphate (IPP) via 1-deoxy-D-xylulose-5-phosphate, labeling experiments with 1-[2H(1)]deoxy-D-xylulose were performed with various higher plants and algae: efficient incorporation was observed into isoprene emitted by Populus, Chelidonium, and Salix, into the phytol moiety of chlorophylls in a red alga (Cyanidium), in two green algae (Scenedesmus, Chlamydomonas), and a higher plant (Lemna). By contrast, 13C-mevalonate applied was incorporated into isoprene and phytol to a much lower extent or not at all. This demonstrates that this '1-deoxy-D-xylulose-5-phosphate pathway' for biosynthesis of plastidic isoprenoids is widely distributed in photosynthetic organisms.

[Sequelae of cholecystectomy]

The removal of the gallbladder is followed by a number of compensatory changes, which in most cases do not result in clinical symptoms: the loss of the pressure reservoir for the bile, the duodenogastric reflux with a subsequent increase in gastric pH and helicobacter infections as well as alterations in bile metabolism. An increased incidence of colon carcinoma has been suggested to be caused by cholecystectomy. However, this might also be due to cholelithiasis. Abdominal symptoms widely regarded as postcholecystectomy syndrome are often due to functional disorders of the gastrointestinal tract and the unrelated to the loss of the gallbladder. Therefore, the expression postcholecystectomy syndrome is imprecise and should not be used in the future. Changes affecting the bile ducts such as sphincter Oddi dyskinesia, stones and stenoses are rare and treatment by endoscopic interventions is generally successful.

Synthesis of heterocyclic platelet activating factor analogues

The synthesis of heterocyclic analogues of the platelet activating factor is described. The preparation starts with acylating rac-tetrahydro-1,3-thiazine-4-carboxylic acid ethyl ester, with palmitoyl chloride to form the amide linkage. Following ester reduction, the phosphocholine part is introduced via 2-chloro-2-oxo-1,3,2-dioxaphospholane and subsequent ring opening with trimethylamine under pressure. Furthermore, the related L-thiazolidine analogue is prepared using the same procedure. In addition the sulfinyl and sulfonyl derivatives of this compound are obtained by oxidation with 3-chloro-perbencoic acid. From one sulfinyl intermediate the diastereomeres are separated and their conformations are determinated by 13C-NMR spectroscopy.

Synthesis of heterocyclic platelet activating factor analogues

The synthesis of heterocyclic analogues of the platelet activating factor is described. The preparation starts with acylating rac-tetrahydro-1,3-thiazine-4-carboxylic acid ethyl ester, with palmitoyl chloride to form the amide linkage. Following ester reduction, the phosphocholine part is introduced via 2-chloro-2-oxo-1,3,2-dioxaphospholane and subsequent ring opening with trimethylamine under pressure. Furthermore, the related L-thiazolidine analogue is prepared using the same procedure. In addition the sulfinyl and sulfonyl derivatives of this compound are obtained by oxidation with 3-chloro-perbencoic acid. From one sulfinyl intermediate the diastereomeres are separated and their conformations are determinated by 13C-NMR spectroscopy.

CNAD: a potent and specific inhibitor of alcohol dehydrogenase

CNAD (5-beta-D-ribofuranosylnicotinamide adenine dinucleotide) is an isosteric and isomeric analogue of NAD, in which the nicotinamide ring is linked to the sugar via a C-glycosyl (C5-C1') bond. CNAD acts as a general dehydrogenase inhibitor but shows unusual specificity and affinity for liver alcohol dehydrogenase (ADH, EC 1.1.1.1). The pattern of inhibition is congruent to 4 nM, with NAD as the variable substrate. These values are 3-5 orders of magnitude smaller than those obtained for CNAD in other dehydrogenases and are comparable to values observed for the tightest binding ADH inhibitors known. The specificity and affinity of CNAD for ADH are likely due to coordination of the zinc cation at the ADH catalytic site by the CNAD pyridine nitrogen. This is supported by kinetic and computational studies of ADH-CNAD complexes. These results are compared with those for a related analogue, CPAD. In this analogue, displacement of the pyridine nitrogen to the opposite side of the ring removes the specificity for ADH.

The differentiation and lineage development of goblet cells in the murine small intestinal crypt: experimental and modelling studies

The objective of this study was to provide a new insight into the origin and lineage development of mucus-producing cells in the small intestinal crypt. For this, new experimental data were obtained from both crypt sections and whole mounts. Model simulation studies were undertaken to investigate which rules are most likely to govern the dynamic cellular development and goblet cell pedigree. We have measured the frequency of mucus-secreting goblet cells (using alcian blue and periodic acid Schiff's stains) at each cell position in the ileal murine crypt. These measurements, made on sections, overestimate the number of goblet cells because of the size and centripetal position of the stained cytoplasm. The correction factor for this overscoring has been measured to be 0.25 by two independent methods. The data suggest that there are about 12 functional goblet cells per crypt many of which retain an ability to divide. We have also determined the labelling index of the crypt goblet cells at each cell position. Spatially, goblet cells exhibit a small degree of clustering in the crypt and show a good mixture with columnar cells. We have adapted our earlier dynamic matrix-based computer stimulation model to take into account goblet cell differentiation. The modelling suggested the following conclusions: firstly, goblet cells do not have their own stem cells but share a common stem cell with the columnar cells; secondly, the goblet lineage differentiates from the transit population two to three generations before the end of the lineage; and thirdly, the decision to switch on goblet properties is stochastic at a specific step in the development of columnar cells.

Synthesis of isosteric analogues of nicotinamide adenine dinucleotide containing C-nucleotide of nicotinamide or picolinamide

Two isosteric analogues of nicotinamide adenine dinucleotide, C-NAD (11) and C-PAD (12), in which the nicotinamide riboside portion is replaced by a C-nucleoside, were synthesized from 5-(beta-D-ribofuranosyl)nicotinamide (7) and 6-(beta-D-ribofuranosyl)picolinamide (8), respectively. Nucleoside 7 was prepared from the 2,3-O-isopropylidene-5-O-(tetrahydropyranyl)-D-ribonolactone (13) and 3-cyano-5-lithiopyridine as reported earlier. Nucleoside 8 was obtained by conversion of the bromo function of the 6-(2,3:4,5-di-O-isopropylidene-D-altro-pentitol-1-yl)-2-bromopyrid ine (14) into a carboxamido group followed by mesylation of the anomeric hydroxyl group to give derivative 18. Treatment of 18 with CF3COOH/CHCl3 caused deisopropylidenation with simultaneous cyclization into the desired 6-(beta-D-ribofuranosyl)picolinamide (8). NAD analogues, C-NAD (11) and C-PAD (12), were synthesized by imidazole-catalyzed coupling of the corresponding 5'-monophosphates of 7 and 8 with the adenosine-5'-monophosphate. Dinucleotide 11 was found to inhibit the proliferation of L1210 cells (IC50 = 7 microM) and to be a good competitive inhibitor of inosine monophosphate dehydrogenase (IMPDH, ID50 = 20 microM) as well as bovine glutamate dehydrogenase (GDH, Ki = 15 microM). Interestingly, C-NAD (11) caused extremely potent noncompetitive inhibition of horse liver alcohol dehydrogenase (ADH, Ki = 1.1 nM), whereas C-PAD (12) was found to be a much less potent competitive inhibitor (Ki = 20 microM) of ADH.

Synthesis and anti-HIV-1 activity of 2'-"up"-fluoro analogues of active anti-AIDS nucleosides 3'-azido-3'-deoxythymidine (AZT) and 2',3'-dideoxycytidine (DDC)

1-(3-Azido-2,3-dideoxy-2-fluoro-beta-D-arabinofuranosyl)thymine (6, F-AZT) and 1-(2,3-dideoxy-2-fluoro-beta-D-threopentofuranosyl)cytosine (12, F-DDC) were synthesized from the potent antiherpes virus nucleosides 1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)thymine (1, FMAU) and 1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-iodocytosine (FIAC) in the hope that introduction of a 2-"up"-fluoro substituent might potentiate the anti-HIV activity of AZT and DDC. FMAU (1) was converted in three steps into 2,3'-anhydro-1-(2-fluoro-2-deoxy-5-O-trityl-beta-D-lyxofuranosyl)thymine (4), which when treated with NaN3 followed by detritylation afforded 6. F-DDC was prepared by two methods. Tritylation of FIAC followed by treatment of the product with thiocarbonyldimidazole afforded the 5'-O-trityl-3'-O-(imidazolyl)thiocarbonyl nucleoside 9. Upon radical reduction of 9 with Bu3SnH and AIBN, 5'-O-trityl-DDC 10 was obtained. Compound 10 was detritylated to give 12, which (when obtained by this procedure) resisted crystallization, but the diacetate 12' was obtained in crystalline form. Alternatively, FAC (14) was converted into N4,O5'-dibenzoyl derivative 15, which was treated with thiocarbonyldiimidazole. Reduction of 16 with Bu3SnH/AIBN followed by debenzoylation afforded 12, which was obtained in crystalline form. F-AZT did not exhibit any significant activity against the human immunodeficiency virus (HIV) in vitro. F-DDC, however, showed activity against HIV-1, but the therapeutic index is much inferior to that of AZT.