Atrial high-rate episodes predict clinical outcome in patients with cardiac resynchronization therapy.

OBJECTIVES: Up to 50% of patients qualified for cardiac resynchronization therapy (CRT) have documented atrial fibrillation (AF) prior to CRT-implantation. This finding is associated with worse prognosis but few studies have evaluated the importance of post-implant device-detected AF. This study aimed to assess the prognostic impact of device-detected atrial high-rate episodes (AHRE), as a surrogate for AF. DESIGN: Data were retrospectively obtained from consecutive patients receiving CRT. Baseline clinical data and data from CRT device-interrogations, performed at a median of 12.2 months after CRT-implantation, were evaluated with regard to prediction of the composite endpoint of death, heart transplant or appropriate shock therapy. Median follow-up time was 51 months post-implant. RESULTS: The study included 377 patients. Preoperative AF was present in 49% and associated with worse outcome. The cumulative burden of AHRE at 12 months post-implant was an independent predictor of the primary endpoint. During the first 12 months after CRT-implantation, AHRE were detected in 25% of the patients with no preoperative diagnosis of AF. This finding was not associated with worse outcome. CONCLUSIONS: In CRT recipients, the cumulative burden of AHRE during the first year of follow-up was associated with worse long-term clinical outcome. Prospective trials are needed to determine if a rhythm control strategy is to be preferred in patients with CRT.

Autonomic influence on atrial fibrillatory process: head-up and head-down tilting.

BACKGROUND: Changes in the autonomic nervous system (ANS) tone are present before, during, and after episodes of atrial fibrillation (AF). Atrial fibrillatory rate (AFR, the inverse of the atrial cycle length) has been used as a surrogate marker for local refractoriness and is a key characteristic of the fibrillatory process in patients with AF. Aim of this study is to assess changes in AFR, as an effect of autonomic balance change. METHODS: Forty patients undergoing cardiac cardioversion for symptomatic persistent AF were included in the study. Surface ECG was recorded during rest, head-down (HDT, -30°), and head-up tilt (HUT, +60°). A median value of AFR was computed in each phase of the protocol. RESULTS: AFR decreased during HDT compared to the baseline (B) condition in all patients but three (median AFR_B = 391 fpm vs. AFR_HDT = 377 fpm, p < .0001). HUT increased AFR, making it significantly higher than HDT and baseline conditions (median AFR_HUT = 396 fpm, p < .0001 vs. B and HDT). Heart rate (HR) increased during HUT, but had a heterogeneous behavior in the population during HDT: about one third of the patients had an HR lower during HDT than during baseline, whereas the remaining two third had an increase in HR during HDT. CONCLUSIONS: Dominant sympathetic/vagal tone during HUT/HDT significantly affects AFR, increasing/decreasing in respect to baseline. It may be worth exploring the possibility that patients with AF of shorter duration can convert to sinus rhythm during HDT.

Transient structure and dynamics in the disordered c-Myc transactivation domain affect Bin1 binding.

The crucial role of Myc as an oncoprotein and as a key regulator of cell growth makes it essential to understand the molecular basis of Myc function. The N-terminal region of c-Myc coordinates a wealth of protein interactions involved in transformation, differentiation and apoptosis. We have characterized in detail the intrinsically disordered properties of Myc-1-88, where hierarchical phosphorylation of S62 and T58 regulates activation and destruction of the Myc protein. By nuclear magnetic resonance (NMR) chemical shift analysis, relaxation measurements and NOE analysis, we show that although Myc occupies a very heterogeneous conformational space, we find transiently structured regions in residues 22-33 and in the Myc homology box I (MBI; residues 45-65); both these regions are conserved in other members of the Myc family. Binding of Bin1 to Myc-1-88 as assayed by NMR and surface plasmon resonance (SPR) revealed primary binding to the S62 region in a dynamically disordered and multivalent complex, accompanied by population shifts leading to altered intramolecular conformational dynamics. These findings expand the increasingly recognized concept of intrinsically disordered regions mediating transient interactions to Myc, a key transcriptional regulator of major medical importance, and have important implications for further understanding its multifaceted role in gene regulation.

Prevalence of severe-to-Profound hearing loss in the adult Swedish population and comparison with cochlear implantation rate.

BACKGROUND: The prevalence of disabling hearing loss is increasing worldwide. However, previous studies on hearing loss prevalence have enrolled small populations or only provided estimates. AIM: To establish the prevalence of severe-to-profound hearing loss (STPHL) in the adult Swedish population and compare it with the cochlear implantation rate in Sweden. MATERIAL AND METHODS: We established a database containing over 15 million audiograms obtained from regions covering > 99% of the Swedish population by extracting audiogram data from the computer software application, Auditbase. We used this database to calculate the percentage of adult patients with bilateral hearing levels ≥ 70 dB. We collected data regarding cochlear implantations in Sweden from the National Board of Welfare and Health. RESULTS: The prevalence of STPHL in the adult Swedish population was 0.28%. There were regional variations in the prevalence and rate of cochlear implantation; however, there was no association between both parameters. CONCLUSIONS: This study presents an updated and reliable prevalence figure for STPHL in Sweden. SIGNIFICANCE: Patients with STPHL have extensive rehabilitation requirements; accordingly, it is important to determine the accurate prevalence of STPHL to inform the allocation of adequate resources.

Polypeptide conjugate binders that discriminate between two isoforms of human carbonic anhydrase in human blood.

Two binder candidates 4-C37L34-B and 3-C15L8-B from a 16-membered set of 42-residue polypeptide conjugates designed to bind human carbonic anhydrase II (HCAII), were shown to bind HCAII with high affinity in a fluorescence-based screening assay. Two carbonic anhydrase isoforms with 60 % homology exist in human blood with HCAI being present in five- to sevenfold excess over HCAII. The ability of the binders to discriminate between HCAI and HCAII was evaluated with regard to what selectivity could be achieved by the conjugation of polypeptides from a 16-membered set to a small organic molecule that binds both isoforms with similar affinities. The polypeptide conjugate 4-C37L34-B bound HCAII with a K(D) of 17 nM and HCAI with a K(D) of 470 nM, that is, with a 30-fold difference in affinity. The corresponding dissociation constants for the complexes formed from 3-C15L8-B and the two carbonic anhydrases were 60 and 390 nM, respectively. This demonstration of selectivity between two very similar proteins is striking in view of the fact that the molecular weight of each one of the conjugate molecules is little more than 5000, the fold is unordered, and the polypeptide sequences were designed de novo and have no prior relationship to carbonic anhydrases. The results suggest that synthetic polypeptide conjugates can be prepared from organic molecules that are considered to be weak binders with low selectivity, yielding conjugates with properties that make them attractive alternatives to biologically generated binders in biotechnology and biomedicine.

Enrichment of ligands with molecular dockings and subsequent characterization for human alcohol dehydrogenase 3.

Alcohol dehydrogenase 3 (ADH3) has been assigned a role in nitric oxide homeostasis due to its function as an S-nitrosoglutathione reductase. As altered S-nitrosoglutathione levels are often associated with disease, compounds that modulate ADH3 activity might be of therapeutic interest. We performed a virtual screening with molecular dockings of more than 40,000 compounds into the active site of human ADH3. A novel knowledge-based scoring method was used to rank compounds, and several compounds that were not known to interact with ADH3 were tested in vitro. Two of these showed substrate activity (9-decen-1-ol and dodecyltetraglycol), where calculated binding scoring energies correlated well with the logarithm of the k (cat)/K (m) values for the substrates. Two compounds showed inhibition capacity (deoxycholic acid and doxorubicin), and with these data three different lines for specific inhibitors for ADH3 are suggested: fatty acids, glutathione analogs, and cholic acids.

Functionally important amino acids in the Arabidopsis thylakoid phosphate transporter: homology modeling and site-directed mutagenesis.

The anion transporter 1 (ANTR1) from Arabidopsis thaliana, homologous to the mammalian members of the solute carrier 17 (SLC17) family, is located in the chloroplast thylakoid membrane. When expressed heterologously in Escherichia coli, ANTR1 mediates a Na(+)-dependent active transport of inorganic phosphate (P(i)). The aim of this study was to identify amino acid residues involved in P(i) binding and translocation by ANTR1 and in the Na(+) dependence of its activity. A three-dimensional structural model of ANTR1 was constructed using the crystal structure of glycerol 3-phosphate/phosphate antiporter from E. coli as a template. Based on this model and multiple sequence alignments, five highly conserved residues in plant ANTRs and mammalian SLC17 homologues have been selected for site-directed mutagenesis, namely, Arg-120, Ser-124, and Arg-201 inside the putative translocation pathway and Arg-228 and Asp-382 exposed at the cytoplasmic surface of the protein. The activities of the wild-type and mutant proteins have been analyzed using expression in E. coli and radioactive P(i) transport assays and compared with bacterial cells carrying an empty plasmid. The results from P(i)- and Na(+)-dependent kinetics indicate the following: (i) Arg-120 and Arg-201 may be important for binding and translocation of the substrate; (ii) Ser-124 may function as a transient binding site for Na(+) ions in close proximity to the periplasmic side; (iii) Arg-228 and Asp-382 may participate in interactions associated with protein conformational changes required for full transport activity. Functional characterization of ANTR1 should provide useful insights into the function of other plant and mammalian SLC17 homologous transporters.

Psychometric validation of the Dutch translation of the quality of life in reflux and dyspepsia (QOLRAD) questionnaire in patients with gastroesophageal reflux disease.

BACKGROUND: The Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire is one of the best-characterized disease-specific instruments that captures health-related problems and symptom-patterns in patients with gastroesophageal reflux disease (GERD). This paper reports the psychometric validation of a Dutch translation of the QOLRAD questionnaire in gastroenterology outpatients with GERD. METHODS: Patients completed the QOLRAD questionnaire at visit 1 (baseline), visit 2 (after 2, 4 or 8 weeks of acute treatment with esomeprazole 40 mg once daily), and visit 4 (after 6 months with on-demand esomeprazole 40 mg once daily or continuous esomeprazole 20 mg once daily). Symptoms were assessed at each visit, and patient satisfaction was assessed at visits 2 and 4. RESULTS: Of the 1166 patients entered in the study, 97.3% had moderate or severe heartburn and 55.5% had moderate or severe regurgitation at baseline. At visit 2, symptoms of heartburn and regurgitation were mild or absent in 96.7% and 97.7%, respectively, and 95.3% of patients reported being satisfied with the treatment. The internal consistency and reliability of the QOLRAD questionnaire (range: 0.83-0.92) supported construct validity. Convergent validity was moderate to low. Known-groups validity was confirmed by a negative correlation between the QOLRAD score and clinician-assessed severity of GERD symptoms. Effect sizes (1.15-1.93) and standardized response means (1.17-1.86) showed good responsiveness to change. GERD symptoms had a negative impact on patients' lives. CONCLUSIONS: The psychometric characteristics of the Dutch translation of the QOLRAD questionnaire were found to be satisfactory, with good reliability and responsiveness to change, although convergent validity was at best moderate.

Validity and reliability of a new, short symptom rating scale in patients with persistent atrial fibrillation.

BACKGROUND: Symptoms related to atrial fibrillation and their impact on health-related quality of life (HRQoL) are often evaluated in clinical trials. However, there remains a need for a properly validated instrument. We aimed to develop and validate a short symptoms scale for patients with AF. METHODS: One hundred and eleven patients with a variety of symptoms related to AF were scheduled for DC cardioversion. The mean age was 67.1 +/- 12.1 years, and 80% were men. The patients completed the new symptoms scale, the Toronto Symptoms Check List (SCL) and the generic Short Form 36 (SF-36) the day before the planned DC cardioversion. Compliance was excellent, with only 1 of 666 answers missing. RESULTS: One item, 'limitations in working capability', was deleted because of a low numerical response rate, as many of the patients were retired. The internal consistency reliability of the remaining six items was 0.81 (Cronbach's alpha). Patients scored highest in the items of 'dyspnoea on exertion', 'limitations in daily life due to AF' and 'fatigue due to AF', with scores of 4.5, 3.3 and 4.5, respectively. There was a good correlation to all relevant SF-36 domains and to the relevant questions of the SCL. The Rasch analyses showed that the items are unidimensional and that they are clearly separated and cover an adequate range. Test-retest reliability was performed in patients who failed DC and was adequate for three of six items, > 0.70. CONCLUSION: The psychometric characteristics of the new short symptoms scale were found to have satisfactory reliability and validity.

Usefulness of N-terminal pro-brain natriuretic Peptide and brain natriuretic peptide to predict cardiovascular outcomes in patients with heart failure and preserved left ventricular ejection fraction.

More than 40% of patients hospitalized with heart failure have preserved left ventricular ejection fraction (HF-PLVEF) and are at high risk for cardiovascular (CV) events. The purpose of this study was to determine the value of N-terminal pro-brain natriuretic peptide (NT-proBNP) and brain natriuretic peptide (BNP) in predicting CV outcomes in patients with HF-PLVEF. Participants with an ejection fraction >40% in the prospective CHARM Echocardiographic Substudy were included in this analysis. Plasma NT-proBNP levels were measured, and 2 cut-offs were selected prospectively at 300 pg/ml and 600 pg/ml. BNP cut-off was set at 100 pg/ml. Clinical characteristics were recorded, and systolic and diastolic function were evaluated by echocardiography. The primary substudy outcome was the composite of CV mortality, hospitalization for heart failure, and myocardial infarction or stroke. A total of 181 patients were included, and there were 17 primary CV events (9.4%) during a median follow-up time of 524 days. In a model including clinical characteristics, echocardiographic measures, and BNP or NT-proBNP, the composite CV event outcome was best predicted by NT-proBNP >300 pg/ml (hazard ratio 5.8, 95% confidence intervals [CI] 1.3 to 26.4, p = 0.02) and moderate or severe diastolic dysfunction on echocardiography. When NT-proBNP >600 pg/ml was used in the model, it was the sole independent predictor of primary CV events (hazard ratio 8.0, 95% CI 2.6 to 24.8, p = 0.0003) as was BNP >100 pg/ml (hazard ratio 3.1, 95% CI 1.2 to 8.2, p = 0.02) in the BNP model. In conclusion, both elevated NT-proBNP and BNP are strong independent predictors of clinical events in patients with HF-PLVEF.

BNP and NT-proBNP predict echocardiographic severity of diastolic dysfunction.

AIMS: To evaluate the best combination of clinical parameters and brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP), to predict diastolic dysfunction (DD) in heart failure with preserved left ventricular ejection fraction (HF-PLEF) as determined by Doppler-echocardiography. METHODS AND RESULTS: HF patients with EF >40% in the CHARM Echocardiographic Substudy were included and classified to have normal diastolic function, or mild, moderate or severe diastolic dysfunction. Plasma BNP and NT-proBNP levels were measured and relevant clinical characteristics recorded. 181 participants were included in this analysis, 72 (40%) had moderate to severe DD. A model including age, sex, BNP, body mass index, history of atrial fibrillation, coronary artery disease, diabetes mellitus, hypertension and left atrial volume was highly predictive of moderate to severe DD; AUC 0.81 (0.73-0.88; p<0.0001). Similarly, substitution of BNP with NT-proBNP resulted in an AUC 0.79 (0.72-0.87; p<0.0001). In these models; BNP>100 pg/ml (OR 6.24 CI 2.42-16.09, p=0.0002), history of diabetes (OR 3.52 CI 1.43-8.70, p=0.006) and NT-proBNP >600 pg/ml (OR 5.93 CI 2.21-15.92, p=0.0004), history of diabetes mellitus (OR 2.75 CI 1.12-6.76, p=0.03) respectively remained independent predictors of DD in HF-PLEF. CONCLUSIONS: Natriuretic peptides were the strongest independent predictors of DD, as determined by Doppler-echocardiography, in HF-PLEF.

A multinational investigation of time and traveling costs in attending anticoagulation clinics.

OBJECTIVES: Anticoagulation is used in patients with atrial fibrillation to reduce the risk of ischemic stroke. The therapy requires regular monitoring and, frequently, dose adjustment. This study aimed to determine the time and traveling costs that patients incur to themselves and society in attending anticoagulation clinics. METHODS: A subset of patients from 105 primary and secondary care clinics allocated to the warfarin arm of SPORTIF III (patients from Australia, France, Portugal, Spain, Sweden, and the UK) completed a questionnaire. Patients indicated the type of transport used for clinic visits, and estimated traveling expenses. Patients were also asked to estimate total traveling and clinic attendance time, and to confirm whether they were currently employed and whether they had to give up time from work to attend the clinic. Time cost of companions was also taken into consideration. Cost per visit was calculated (euro, 2003 prices). RESULTS: Questionnaires for a total of 381 patients were analyzed, with the majority of patients from Sweden (n = 130) and the UK (n = 101). Mean cost to patients varied widely between countries, ranging from euro6.9 (France) to euro20.5 (Portugal) per visit. For most countries, time costs (value of lost working and leisure time) were the main driver of costs. Mean time cost to society ranged from euro5.6 (France) to euro31.7 (Portugal) per visit. CONCLUSIONS: Patients incur considerable costs when visiting anticoagulation clinics, and these costs vary by country. The results suggest the importance of taking a broad economic perspective when considering the cost-effectiveness of warfarin.

An international comparison of the burden of illness in patients with dyspepsia.

BACKGROUND/AIMS: This study investigates the symptoms and the impact of symptoms on health-related quality of life (HRQL) in patients consulting with dyspepsia. METHODS: Consecutive patients with a diagnosis of dyspepsia were recruited from primary and secondary care in Germany, Hungary, Italy, Poland, South Africa and Spain. Investigators assessed symptom frequency and severity, and subjects completed the following questionnaires: the Gastrointestinal Symptom Rating Scale (GSRS), the Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire, the Hospital Anxiety and Depression (HAD) scale and the Short Form 36 (SF-36). RESULTS: 853 dyspepsia patients were included. Mean GSRS scores showed that patients were most troubled by abdominal pain and indigestion. QOLRAD scores indicated that symptoms caused emotional distress, food/drink problems and reduced vitality, with a lesser effect on sleep and physical functioning. Mean SF-36 scores were lower than mean normative values for all domains, indicating that patients had a worse HRQL than the normal population, particularly for Bodily Pain, Role Physical and Role Emotional. Of patients in each country, 18-43% were anxious and 11-21% were depressed. CONCLUSIONS: Patients with dyspepsia have reduced HRQL because their symptoms - particularly abdominal pain and indigestion - cause emotional distress, problems with food and drink, and impaired vitality.

Reliability and validity of the Gastrointestinal Symptom Rating Scale (GSRS) and Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire in dyspepsia: a six-country study.

BACKGROUND: Symptoms of dyspepsia significantly disrupt patients' lives and reliable methods of assessing symptom status are important for patient management. The aim of the current study was to document the psychometric characteristics of the Gastrointestinal Symptom Rating Scale (GSRS) and the Quality of Life in Reflux and Dyspepsia questionnaire (QOLRAD) in Afrikaans, German, Hungarian, Italian, Polish and Spanish patients with dyspepsia. METHODS: 853 patients with symptoms of dyspepsia completed the GSRS, the QOLRAD, the 36-item Short-Form Health Survey (SF-36) and the Hospital Anxiety and Depression scale. RESULTS: The internal consistency reliability of the GSRS was 0.43-0.87 and of the QOLRAD 0.79-0.95. Test-retest reliability of the GSRS was 0.36-0.75 and of the QOLRAD 0.41-0.82. GSRS Abdominal pain domain correlated significantly with all QOLRAD domains in most language versions, and with SF-36 Bodily pain in all versions. QOLRAD domains correlated significantly with the majority of SF-36 domains in most versions. Both questionnaires were able to differentiate between patients whose health status differed according to symptom frequency and severity. CONCLUSION: The psychometric characteristics of the different language versions of the GSRS and QOLRAD were found to be good, with acceptable reliability and validity. The GSRS and QOLRAD were found to be useful for evaluating dyspeptic symptoms and their impact on patients' daily lives in multinational clinical trials.

Characterization of health-related quality of life in heart failure patients with preserved versus low ejection fraction in CHARM.

BACKGROUND: Limited comparative studies assessing the health-related quality of life (HRQL) in heart failure (HF) patients with preserved vs. low ejection fraction (LVEF) have been disparate. AIMS: The aims of this study were a) to characterize HRQL in a large population of HF patients with preserved and low LVEF and b) to determine the factors associated with worse HRQL. METHODS: Patients with symptomatic HF (NYHA Class II-IV) enrolled in the Candesartan in Heart Failure: Assessment of Reduction in Mortality and Morbidity (CHARM) HRQL study completed the Minnesota Living with Heart Failure questionnaire at randomization. Patients were stratified into 2 HF cohorts: preserved LVEF (>40%) and low LVEF (

Molecular model of human CYP21 based on mammalian CYP2C5: structural features correlate with clinical severity of mutations causing congenital adrenal hyperplasia.

Enhanced understanding of structure-function relationships of human 21-hydroxylase, CYP21, is required to better understand the molecular causes of congenital adrenal hyperplasia. To this end, a structural model of human CYP21 was calculated based on the crystal structure of rabbit CYP2C5. All but two known allelic variants of missense type, a total of 60 disease-causing mutations and six normal variants, were analyzed using this model. A structural explanation for the corresponding phenotype was found for all but two mutants for which available clinical data are also discrepant with in vitro enzyme activity. Calculations of protein stability of modeled mutants were found to correlate inversely with the corresponding clinical severity. Putative structurally important residues were identified to be involved in heme and substrate binding, redox partner interaction, and enzyme catalysis using docking calculations and analysis of structurally determined homologous cytochrome P450s (CYPs). Functional and structural consequences of seven novel mutations, V139E, C147R, R233G, T295N, L308F, R366C, and M473I, detected in Scandinavian patients with suspected congenital adrenal hyperplasia of different severity, were predicted using molecular modeling. Structural features deduced from the models are in good correlation with clinical severity of CYP21 mutants, which shows the applicability of a modeling approach in assessment of new CYP21 mutations.

Immunoseq: the identification of functionally relevant variants through targeted capture and sequencing of active regulatory regions in human immune cells.

BACKGROUND: The observation that the genetic variants identified in genome-wide association studies (GWAS) frequently lie in non-coding regions of the genome that contain cis-regulatory elements suggests that altered gene expression underlies the development of many complex traits. In order to efficiently make a comprehensive assessment of the impact of non-coding genetic variation in immune related diseases we emulated the whole-exome sequencing paradigm and developed a custom capture panel for the known DNase I hypersensitive site (DHS) in immune cells - "Immunoseq". RESULTS: We performed Immunoseq in 30 healthy individuals where we had existing transcriptome data from T cells. We identified a large number of novel non-coding variants in these samples. Relying on allele specific expression measurements, we also showed that our selected capture regions are enriched for functional variants that have an impact on differential allelic gene expression. The results from a replication set with 180 samples confirmed our observations. CONCLUSIONS: We show that Immunoseq is a powerful approach to detect novel rare variants in regulatory regions. We also demonstrate that these novel variants have a potential functional role in immune cells.

Unfolding a folding disease: folding, misfolding and aggregation of the marble brain syndrome-associated mutant H107Y of human carbonic anhydrase II.

Most loss-of-function diseases are caused by aberrant folding of important proteins. These proteins often misfold due to mutations. The disease marble brain syndrome (MBS), known also as carbonic anhydrase II deficiency syndrome (CADS), can manifest in carriers of point mutations in the human carbonic anhydrase II (HCA II) gene. One mutation associated with MBS entails the His107Tyr substitution. Here, we demonstrate that this mutation is a remarkably destabilizing folding mutation. The loss-of-function is clearly a folding defect, since the mutant shows 64% of CO(2) hydration activity compared to that of the wild-type at low temperature where the mutant is folded. On the contrary, its stability towards thermal and guanidine hydrochloride (GuHCl) denaturation is highly compromised. Using activity assays, CD, fluorescence, NMR, cross-linking, aggregation measurements and molecular modeling, we have mapped the properties of this remarkable mutant. Loss of enzymatic activity had a midpoint temperature of denaturation (T(m)) of 16 degrees C for the mutant compared to 55 degrees C for the wild-type protein. GuHCl-denaturation (at 4 degrees C) showed that the native state of the mutant was destabilized by 9.2kcal/mol. The mutant unfolds through at least two equilibrium intermediates; one novel intermediate that we have termed the molten globule light state and, after further denaturation, the classical molten globule state is populated. Under physiological conditions (neutral pH; 37 degrees C), the His107Tyr mutant will populate the molten globule light state, likely due to novel interactions between Tyr107 and the surroundings of the critical residue Ser29 that destabilize the native conformation. This intermediate binds the hydrophobic dye 8-anilino-1-naphthalene sulfonic acid (ANS) but not as strong as the molten globule state, and near-UV CD reveals the presence of significant tertiary structure. Notably, this intermediate is not as prone to aggregation as the classical molten globule. As a proof of concept for an intervention strategy with small molecules, we showed that binding of the CA inhibitor acetazolamide increases the stability of the native state of the mutant by 2.9kcal/mol in accordance with its strong affinity. Acetazolamide shifts the T(m) to 34 degrees C that protects from misfolding and will enable a substantial fraction of the enzyme pool to survive physiological conditions.

Patient perception of the effect of treatment with candesartan in heart failure. Results of the candesartan in heart failure: assessment of reduction in mortality and morbidity (CHARM) programme.

AIMS: To evaluate the effect of the angiotensin receptor blocker candesartan on patients' perception of symptoms, using the McMaster Overall treatment evaluation (OTE), in a broad spectrum of patients with chronic heart failure (CHF). METHODS AND RESULTS: Patients with symptomatic CHF, randomised in the CHARM Programme in North America (n=2498), were studied. OTE was assessed at baseline, at 6, 14 and 26 months and the patient's final or closing visit. Patient's status was classified as "improved (score +1 to +7)", "unchanged (score 0)" or "deteriorated (score -1 to -7)" at the end of the study compared to baseline. Both a simple "last visit carried forward" (LVCF) analysis and "worst rank carried forward" (WRCF) analysis (where patients who died were allocated the worst OTE score) were used. In the LVCF analysis, compared to placebo, more candesartan patients improved (37.7% versus 33.5%) and fewer worsened (10.8% versus 12.0%) in OTE (p=0.017). The WRCF analysis also showed better overall OTE scores with candesartan compared to placebo (p=0.029). There was no heterogeneity in the response to candesartan between the CHARM component trials or across four exploratory sub-groups (age, sex, NYHA class and beta-blocker). CONCLUSIONS: Candesartan was shown to be better than placebo, when using the McMaster OTE to measure patient perception of treatment. More patients treated with candesartan reported improvement and fewer reported deterioration. This benefit was obtained when candesartan was added to extensive background therapy and is consistent with the benefits of candesartan on NYHA class, hospital admission for worsening heart failure and mortality.

Impact of irritable bowel syndrome on patients' lives: development and psychometric documentation of a disease-specific measure for use in clinical trials.

OBJECTIVE: To develop a disease-specific questionnaire to capture the impact of irritable bowel syndrome (IBS) and its treatment on patients' lives, the Irritable Bowel Syndrome Impact Scale (IBS-IS). PATIENTS AND METHODS: One hundred and fifty-five IBS patients participated (126 (81%) female; age (mean+/-SD) 45.5+/-12.4 years). We developed the initial 39 items from the literature, available IBS-specific instruments and input from physicians, nurses and patients. We deleted IBS-IS items with a high ceiling effect, items that measured a different construct and items showing a high correlation (r>0.90) with another item and with Rasch analysis, leaving 26 items. We then applied exploratory factor analysis to examine domain groupings. Subjects completed the IBS-IS instrument, the Gastrointestinal Symptom Rating Scale for IBS (GSRS-IBS), Short Form-36 (SF-36), Visceral Sensitivity Index (VSI), and Hospital Anxiety and Depression (HAD) scale. Internal consistency, construct validity and discriminate validity were assessed. RESULTS: The 26 items represented five domains: fatigue, impact on daily activities, sleep disturbance, emotional distress and eating habits. The internal consistency reliability for the domains was 0.87 to 0.96. Most associations between similar constructs in the IBS-IS, GSRS-IBS, SF-36, VSI, and HAD were >0.40. Each IBS-IS domain score decreased with increasing IBS symptom severity (P<0.05), and the patients scored >5 score units lower than a US general population scored on all eight SF-36 dimensions. CONCLUSION: The IBS-IS is a short, user-friendly instrument with excellent psychometric properties that has potential usefulness for clinical trials.