ABSTRACT
BACKGROUND: Vitamin-K antagonists (VKAs) have widely been replaced by non-VKA oral anticoagulants (NOACs). This includes Austria, Germany and Switzerland, where as VKA, instead of warfarin, the much longer-acting phenprocoumon is used, which was not compared to NOACs in clinical trials. METHODS: Using administrative data from a large German health insurance, we included all anticoagulation-naïve patients with a first prescription of a NOAC or VKA between 2012 and 2020. We analysed overall survival, major adverse cardiac and cerebrovascular events, major thromboembolic events and major bleeding. RESULTS: Overall, 570,137 patients were included (apixaban: 26.9%, dabigatran: 4.6%, edoxaban: 8.8%, rivaroxaban: 39.1% and VKA: 20.7% of these 99.4% phenprocoumon). In the primary analysis using a 1:1 propensity score matching-cohort (PSM-cohort), a significantly higher overall mortality was found for apixaban, edoxaban and rivaroxaban (all p < 0.001) but not for dabigatran (p = 0.13) compared to VKA. In this PSM-cohort, 5-year mortality was 22.7% for apixaban versus 12.7% for VKA, 19.5% for edoxaban versus 11.4% for VKA, 16.0% for rivaroxaban versus 12.3% for VKA (all p < 0.001) and 13.0% for dabigatran versus 12.8% for VKA (p = 0.06). The observed effect was confirmed in sensitivity analyses using un-weighted and three different weighted Fine-Gray regression models on the basis of the entire cohort. CONCLUSIONS: In this large real-world analysis, apixaban, edoxaban and rivaroxaban, but not dabigatran, were associated with worse survival compared to VKA. These findings, consistent with a few other studies including phenprocoumon, cast profound doubts on the unreflected, general use of NOACs. Randomized trials should assess whether phenprocoumon might actually be superior to NOACs.
Subject(s)
Anticoagulants , Dabigatran , Pyrazoles , Pyridines , Pyridones , Rivaroxaban , Thiazoles , Vitamin K , Humans , Rivaroxaban/therapeutic use , Rivaroxaban/adverse effects , Female , Dabigatran/therapeutic use , Dabigatran/adverse effects , Male , Germany/epidemiology , Pyridones/therapeutic use , Pyridones/adverse effects , Aged , Retrospective Studies , Anticoagulants/therapeutic use , Anticoagulants/adverse effects , Thiazoles/therapeutic use , Thiazoles/adverse effects , Pyridines/therapeutic use , Pyrazoles/therapeutic use , Vitamin K/antagonists & inhibitors , Hemorrhage/chemically induced , Hemorrhage/mortality , Middle Aged , Aged, 80 and over , Factor Xa Inhibitors/therapeutic use , Factor Xa Inhibitors/adverse effects , Propensity Score , Thromboembolism/prevention & control , Thromboembolism/mortalityABSTRACT
Background: Peripheral artery disease (PAD) frequently leads to hospital admission. Sex related differences in in-patient care are a current matter of debate. Patients and methods: Data were provided from the German national in-patient sample provided by the Federal Bureau of Statistics (DESTATIS). Trends on risk profiles, therapeutic procedures, and outcomes were evaluated from 2014 until 2019 stratified by sex and PAD severity. Results: Two-thirds of an annual >191,000 PAD in-patient cases applied to male sex. Chronic limb-threatening ischemia (CLTI) was recorded in 49.6% of male and 55.2% of female cases (2019). CLTI was as a major risk factor of in-hospital amputation (OR 229) and death (OR 10.5), whereas endovascular revascularisation (EVR) with drug-coated devices were associated with decreased risk of in-hospital amputation (OR 0.52; all p<0.001). EVR applied in 47% of CLTI cases compared to 71% in intermittent claudication (IC) irrespective of sex. In-hospital mortality was 4.3% in male vs. 4.8% in female CLTI cases, minor amputations 18.4% vs. 10.9%, and major amputation 7.5% vs. 6.0%, respectively (data 2019; all p<0.001). After adjustment, female sex was associated with lower risk of amputation (OR 0.63) and death (OR 0.96) during in-patient stay. Conclusions: Male PAD patients were twice as likely to be admitted for in-patient treatment despite equal PAD prevalence in the general population. Among in-patient cases, supply with invasive therapy did not relevantly differ by sex, however is strongly reduced in CLTI. CLTI is a major risk factor of adverse short-term outcomes, whereas female sex was associated with lower risk of in-patient amputation and/or death.
Subject(s)
Endovascular Procedures , Peripheral Arterial Disease , Humans , Male , Female , Ischemia/diagnosis , Ischemia/epidemiology , Ischemia/therapy , Treatment Outcome , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/surgery , Intermittent Claudication/diagnosis , Intermittent Claudication/epidemiology , Intermittent Claudication/therapy , Risk Factors , Limb Salvage , Retrospective Studies , Chronic DiseaseABSTRACT
OBJECTIVE: Chronic limb threatening ischaemia (CLTI) has a devastating prognosis with high rates of lower limb amputation (LLA) and deaths. This is an illustration of contemporary management and the long term fate of patients after ischaemic LLA, particularly with respect to sex, using real world data. METHODS: This was a multisectoral cross sectional and longitudinal analysis of health claims data from the largest German health insurance database (AOK). Data of 39 796 propensity score matched patients hospitalised for ischaemic LLA between 2010 and 2018 were analysed for cardiovascular comorbidities, treatment, and for subsequent cardiovascular and limb events, with a distinct focus on sex. Matching was performed, to ensure that the rate of major amputations and the age distribution were equal in both groups (in both sexes). An observation period of two years before index and a follow up (FU) period until 2019 were included. RESULTS: Before index amputation, 68% of patients had received any kind of peripheral revascularisation. The use of statins (37.0% vs. 42.6%) and antithrombotic substances (54.9% vs. 61.8%) was lower in women than in men (p < .001). During two year FU, cardiovascular and limb events occurred among women and men as follows: limb re-amputation (26.7% vs. 31.2%), myocardial infarction (10.9% vs. 14.5%), stroke (20.8% vs. 20.7%), and death from any cause (51.0% vs. 53.3%, p < .001 except for stroke). After adjustment for cardiovascular comorbidities and vascular procedures, female sex was associated with a higher probability of death (HR 1.04, 95% CI 1.04 - 1.04). CONCLUSION: Patients undergoing ischaemic LLA still have a poor prognosis marked by high rates of recurrent cardiovascular and limb events resulting in a > 50% mortality rate within two years. The continuous lack of guideline recommended therapies, particularly in women, may be associated with the persisting poor outcome, necessitating urgent further investigation.
Subject(s)
Peripheral Arterial Disease , Stroke , Humans , Female , Male , Sex Characteristics , Cross-Sectional Studies , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/surgery , Ischemia/diagnosis , Ischemia/surgery , Amputation, Surgical , Stroke/surgery , Lower Extremity/blood supply , Treatment Outcome , Risk Factors , Limb Salvage , Retrospective StudiesABSTRACT
BACKGROUND: Cardiovascular disease is often associated with chronic kidney disease (CKD), resulting in an increased risk for poor outcome. We sought to determine short-term mortality and overall survival in ST-elevation myocardial infarction (STEMI) patients with different stages of CKD. METHODS: In our retrospective cohort study with health insurance claims data of the Allgemeine Ortskrankenkasse (AOK), anonymized data of all STEMI patients hospitalized between 2010 and 2017 were analyzed regarding presence and severity of concomitant CKD. RESULTS: A total of 175,187 patients had an index-hospitalisation for STEMI (without CKD: 78.6% patients, CKD stage 1: 0.8%, CKD stage 2: 4.8%, CKD stage 3: 11.7%, CKD stage 4: 2.8%, CKD stage 5: 0.7%, CKD stage 5d: 0.6%). Patients with CKD were older and had more co-morbidities than patients without CKD. With increasing CKD severity, patients received less revascularization therapies (91.2%, 85.9%, 87.0%, 81.8%, 71.7%, 76.9% and 78.6% respectively, p < 0.001). After 1 year, guideline-recommended medications were prescribed less frequently in advanced CKD (83.4%, 79.3%, 81.5%, 74.7%, 65.0%, 59.4% and 53.7%, respectively, p < 0.001). CKD stages 4, 5 and 5d as well as chronic limb threatening ischemia (CLTI) were associated with decreased overall survival [CKD stage 4: hazard ratio (HR) 1.72; 95% CI 1.66-1.78; CKD stage 5: HR 2.55; 95% CI 2.37-2.73; CKD stage 5d: 5.64; 95% CI 5.42-5.86; CLTI: 2.06; 95% CI 1.98-2.13; all p < 0.001]. CONCLUSIONS: CKD is a frequent co-morbidity in patients with STEMI and is associated with a worse prognosis especially in advanced stages. Guideline-recommended therapies in patients with STEMI and CKD are still underused.
Subject(s)
Anterior Wall Myocardial Infarction , Percutaneous Coronary Intervention , Renal Insufficiency, Chronic , ST Elevation Myocardial Infarction , Humans , ST Elevation Myocardial Infarction/diagnosis , ST Elevation Myocardial Infarction/therapy , ST Elevation Myocardial Infarction/complications , Retrospective Studies , Prognosis , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/therapy , Anterior Wall Myocardial Infarction/complications , Arrhythmias, Cardiac/complications , Hospitals , Kidney/physiology , Hospital Mortality , Risk Factors , Treatment Outcome , Percutaneous Coronary Intervention/adverse effectsABSTRACT
AIMS: The prevalence of chronic limb-threatening ischaemia (CLTI) is increasing and available data often derive from cohorts with various selection criteria. In the present study, we included CLTI patients and studied sex-related differences in their risk profile, vascular procedures, and long-term outcome. METHODS AND RESULTS: We analysed 199 953 unselected patients of the largest public health insurance in Germany (AOK: Local healthcare funds), hospitalized between 2010 and 2017 for a main diagnosis of CLTI. A baseline period of 2 years before index hospitalization to assess comorbidities and previous procedures, and a follow-up period until 2018 were included. Female CLTI patients were older (median 81.4 vs. 73.8 years in males; P < 0.001) and more often diagnosed with hypertension, atrial fibrillation, chronic heart failure, and chronic kidney disease. Male patients suffered more frequently from diabetes mellitus, dyslipidaemia, smoking, cerebrovascular disease, and chronic coronary syndrome (all P < 0.001). Within hospitalized CLTI patients, females represent the minority (43% vs. 57%; P < 0.001) and during index hospitalization, women underwent less frequently diagnostic angiographies (67 vs. 70%) and revascularization procedures (61 vs. 65%; both P < 0.001). Moreover, women received less frequently guideline-recommended drugs like statins (35 vs. 43%) and antithrombotic therapy (48 vs. 53%; both P < 0.001) at baseline. Interestingly, after including age and comorbidities in a Cox regression analysis, female sex was associated with increased overall-survival (OS) [hazard ratio (HR) 0.95; 95% confidence interval (CI) 0.94-0.96] and amputation-free survival (AFS) (HR 0.84; 95% CI 0.83-0.85; both P < 0.001). CONCLUSION: Female patients with CLTI were older, underwent less often vascular procedures, and received less frequently guideline-recommended medication. Nevertheless, female sex was independently associated with better OS and AFS during follow-up.
Subject(s)
Peripheral Arterial Disease , Amputation, Surgical , Chronic Disease , Chronic Limb-Threatening Ischemia , Female , Humans , Ischemia/therapy , Male , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/therapy , Progression-Free Survival , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment OutcomeABSTRACT
AIM OF THE STUDY: The aim of our study was to analyse sex-specific differences in diagnosis and treatment of patients with lower extremity artery disease (LEAD) at Rutherford stage (RF) 1-3, based on secondary data. Furthermore, we focussed on the influence of the biological sex on short- and long-term outcome. METHODS: The GenderVasc project is carried out in cooperation with the AOK Research Institute (WIdO). As data basis, anonymized routine data from all insured patients of the AOK were used. All patients hospitalized due to a main diagnosis of LEAD at RF 1-3 were included and in addition to the multisectoral cross-sectional analysis, longitudinal analysis (follow-up of up to 10 years) of the health claims data was performed and evaluated. RESULTS: Our secondary data analysis of 42,197 patients with intermittent claudication (IC, LEAD at RF 1-3) showed that male patients were more often hospitalized due to LEAD, while women were older at time-point of index hospitalisation (female: 72.6 vs. male: 66.4 years). Fewer vascular procedures (diagnostic angiography and revascularisation) were carried out in females. Moreover, the prescription of guideline-recommended medications (statins and antithrombotic therapy) was lower in women compared to men. Multivariable Cox regression showed, after adjusting for age, cardiovascular risk profile and performed vascular procedure, that female sex was protective with respect to overall survival and progression of LEAD (progress to chronic limb-threatening ischemia or ischemic amputation). CONCLUSION: In Germany, female LEAD patients were older and less likely to receive guideline-recommended therapy, while female sex is protective in terms of overall survival and progression of LEAD. The extent to which increased age or the presence of other comorbidities influence the decision for or against a vascular procedure can only be assumed from a secondary data analysis. Furthermore, the prescription of drugs in multimorbid patients is challenging and the compliance of the patients with prescribed medication intake is not part of our analysis. Nevertheless, targeted analysis, as in the GenderVasc project, are urgently needed to identify and describe differences in the medical care between the sexes.
Subject(s)
Peripheral Arterial Disease , Female , Humans , Male , Cross-Sectional Studies , Germany/epidemiology , Limb Salvage , Lower Extremity/blood supply , Lower Extremity/surgery , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/therapy , Retrospective Studies , Risk Factors , Secondary Data Analysis , Treatment Outcome , Sex Factors , Sex DistributionABSTRACT
Invited for the cover of this issue is the group of Artur Krezel at the University of Wroclaw in collaboration with Lars Hemmingsen at The University of Copenhagen and Eva Freisinger at the University of Zürich. The image depicts the outcomes of HgII interactions with Rad50 protein. Read the full text of the article at 10.1002/chem.202202738.
Subject(s)
Mercury , Zinc , Hydrogen-Ion ConcentrationABSTRACT
In nature, thiolate-based systems are the primary targets of divalent mercury (HgII ) toxicity. The formation of Hg(Cys)x cores in catalytic and structural protein centers mediates mercury's toxic effects and ultimately leads to cellular damage. Multiple studies have revealed distinct HgII -thiolate coordination preferences, among which linear HgII complexes are the most commonly observed in solution at physiological pH. Trigonal or tetrahedral geometries are formed at basic pH or in tight intraprotein Cys-rich metal sites. So far, no interprotein tetrahedral HgII complex formed at neutral pH has been reported. Rad50 protein is a part of the multiprotein MRN complex, a major player in DNA damage-repair processes. Its central region consists of a conserved CXXC motif that enables dimerization of two Rad50 molecules by coordinating ZnII . Dimerized motifs form a unique interprotein zinc hook domain (Hk) that is critical for the biological activity of the MRN. Using a series of length-differentiated peptide models of the Pyrococcus furiosus zinc hook domain, we investigated its interaction with HgII . Using UV-Vis, CD, PAC, and 199 Hgâ NMR spectroscopies as well as anisotropy decay, we discovered that all Rad50 fragments preferentially form homodimeric Hg(Hk)2 species with a distorted tetrahedral HgS4 coordination environment at physiological pH; this is the first example of an interprotein mercury site displaying tetrahedral geometry in solution. At higher HgII content, monomeric HgHk complexes with linear geometry are formed. The Hg(Cys)4 core of Rad50 is extremely stable and does not compete with cyanides, NAC, or DTT. Applying ITC, we found that the stability constant of the Rad50 Hg(Hk)2 complex is approximately three orders of magnitude higher than those of the strongest HgII complexes known to date.
Subject(s)
Mercury , Zinc , Zinc/chemistry , Mercury/chemistry , Metals , DNA Repair , Hydrogen-Ion ConcentrationABSTRACT
Background: Sex-related differences may influence the outcome of endovascular revascularization (EVR) in patients with lower extremity arterial disease (LEAD) even under optimized healthcare supply. Patients and methods: LEAD patients who underwent EVR at the Department of Cardiology I - Coronary and Peripheral Vascular Disease, Heart Failure, University Hospital Muenster, Germany between 2014 and 2016 were included into the retrospective study. Detailed information on risk factors and co-morbidities, medication, LEAD related measures, and interventional parameters were assessed. Outcome defined as technical success rate, complications, and mortality was analyzed up to 12 months follow-up. Results: In total, 165 female and 437 male LEAD patients were included. Women and men presented with comparable severity of LEAD in terms of critical limb threatening ischemia (46.2%), wound status (34.9%), and amputation rate (9.6%, all n.s.) at index. Intake of platelet inhibitors (65.8% female vs. 70.0% male), oral anticoagulants (21.3% vs. 25.4%), and statins (65.6% vs. 76.0%) was observed less frequently in female patients. Against the background of high technical success (85%), in-hospital death (0.8%), severe adverse cardiac (MCE; 1.7%), and limb events (MALE; 6.1%) occurred at low rates in either sex. Adjusted long-term mortality was not affected by patients' sex (female HR 0.755; p=0.312). Conclusions: Despite critical LEAD stages in every second patient, EVR was performed safe with high technical success rates in female and male patients. Long-term outcomes were observed at comparatively low rates in both sexes at the specialized vascular center. During aftercare, supply with statin therapy turned out improvable particularly in female LEAD patients.
Subject(s)
Endovascular Procedures , Peripheral Arterial Disease , Arteries , Endovascular Procedures/adverse effects , Female , Hospital Mortality , Humans , Ischemia/surgery , Limb Salvage , Lower Extremity , Male , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/surgery , Retrospective Studies , Risk Factors , Time Factors , Treatment OutcomeABSTRACT
BACKGROUND: Peripheral arterial occlusive disease (PAOD) is an atherosclerotic vascular disease with high morbidity and mortality. A consistent medication-based secondary prevention is part of the essential and evidence-based treatment of PAOD. The aim of this study was to ascertain the status quo of medicinal secondary prevention based on submitted prescriptions. METHODS: In the time period from 2014 to 2017 patients with a confirmed PAOD coding (I70.2-/I73.9-) were identified based on secondary data of the Association of Statutory Health Insurance Physicians Westphalia-Lippe (KVWL). The prescriptions submitted with respect to platelet inhibitors, oral anticoagulants, lipid lowering therapy (LLT) and angiotensin-converting enzyme (ACE) inhibitors in the fourth quarter year after diagnosis coding were collated. RESULTS: In the diagnosis period 2014/2015 a total of 238,397 patients had PAOD in the catchment area of the KVWL. The proportion of submitted prescriptions in the fourth quarter year after diagnosis was 25.9% for LLT, 13.6% for acetylsalicylic acid, 4.5% for clopidogrel, 5.5% for vitamin K antagonists (VKA), 3.5% for non-vitamin Kdependent oral anticoagulants (NOAC) and 26.8% for ACE inhibitors. Over the course of the 3 years (nâ¯= 241,375 patients with PAOD 2016/2017) the proportion of submitted prescriptions for all substances except VKA increased (pâ¯< 0.001), whereby the largest relative increase was noted for NOAC (relative increase of 81.7%). CONCLUSION: The guideline-conform medicinal secondary prevention in patients with PAOD in Germany is still in need of improvement. A consistent implementation of evidence-based medicinal secondary prevention harbors a great potential for improvement of the overall prognosis in patients with PAOD.
Subject(s)
Arterial Occlusive Diseases , Peripheral Arterial Disease , Anticoagulants/therapeutic use , Aspirin , Humans , Peripheral Arterial Disease/drug therapy , Peripheral Arterial Disease/epidemiology , Peripheral Arterial Disease/prevention & control , Platelet Aggregation Inhibitors/therapeutic use , Secondary PreventionABSTRACT
AIMS: Drug-eluting devices (DED) represent a well-established therapy being widely used for endovascular revascularization (EVR) of peripheral vessels. Recent data indicate a two-fold increased long-term mortality in patients treated with paclitaxel-based DED. The subsequent safety concerns affected international regulatory authorities to enunciate several alerts for further application of DED. METHODS AND RESULTS: In 9.2 million insurants of the German BARMER Health Insurance, data on the application of paclitaxel-based drug-eluting stents (DES) and drug-coated balloons (DCB) were retrieved from their introduction on the market in 2007 until present. All patients with first EVR between 2007 and 2015 were indexed and followed until 31 December 2017. Each subsequently applied DES, DCB, bare-metal stent, and uncoated balloon was included in further analyses. Multivariable Cox regression analysis considered potential non-linear time-dependent hazard ratios (HRs) of DES and DCB over 11 years. We identified 64 771 patients who underwent 107 112 EVR procedures using 23 137 DED. Multivariable Cox regression analysis showed paclitaxel-based DES not to be associated with increased long-term mortality for over 11 years past application (all P > 0.057). DCB was associated with decreased long-term mortality for the first year past application (HR 0.92; P < 0.001), and indifferent correlation in the years thereafter (all P > 0.202). CONCLUSION: Our real-world analysis showed no evidence for increased mortality associated with paclitaxel-based DED for over 11 years.
Subject(s)
Cardiovascular Agents , Drug-Eluting Stents , Peripheral Arterial Disease , Femoral Artery , Humans , Paclitaxel , Peripheral Arterial Disease/therapy , Stents , Treatment OutcomeABSTRACT
AIMS: To evaluate the use of novel oral anticoagulants (NOACs) compared with vitamin K antagonists (VKAs) in adult congenital heart disease (ACHD) and assess outcome in a nationwide analysis. METHODS AND RESULTS: Using data from one of Germany's largest Health Insurers, all ACHD patients treated with VKAs or NOACs were identified and changes in prescription patterns were assessed. Furthermore, the association between anticoagulation regimen and complications including mortality was studied. Between 2005 and 2018, the use of oral anticoagulants in ACHD increased from 6.3% to 12.4%. Since NOACs became available their utilization increased constantly, accounting for 45% of prescribed anticoagulants in ACHD in 2018. Adult congenital heart disease patients on NOACs had higher thromboembolic (3.8% vs. 2.8%), MACE (7.8% vs. 6.0%), bleeding rates (11.7% vs. 9.0%), and all-cause mortality (4.0% vs. 2.8%; all P < 0.05) after 1 year of therapy compared with VKAs. After comprehensive adjustment for patient characteristics, NOACs were still associated with increased risk of MACE (hazard rate-HR 1.22; 95% CI 1.09-1.36) and increased all-cause mortality (HR 1.43; 95% CI 1.24-1.65; both P < 0.001), but also bleeding (HR 1.16; 95% CI 1.04-1.29; P = 0.007) during long-term follow-up. CONCLUSION: Despite the lack of prospective studies in ACHD, NOACs are increasingly replacing VKAs and now account for almost half of all oral anticoagulant prescriptions. Particularly, NOACs were associated with excess long-term risk of MACE, and mortality in this nationwide analysis, emphasizing the need for prospective studies before solid recommendations for their use in ACHD can be provided.
Subject(s)
Anticoagulants , Atrial Fibrillation , Heart Defects, Congenital , Stroke , Administration, Oral , Adult , Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Atrial Fibrillation/drug therapy , Heart Defects, Congenital/complications , Heart Defects, Congenital/drug therapy , Humans , Practice Patterns, Physicians' , Prospective Studies , Stroke/drug therapy , Vitamin KABSTRACT
Metallothioneins (MTs) are a large superfamily of ubiquitous cysteine-rich metalloproteins with main functions in metal ion homeostasis and detoxification. Neclu_MT1 is a metallothionein from the aquatic fungus Heliscus lugdunensis and so far the only known MT that is solely induced by CdII but not by ZnII or copper ions. In addition to eight cysteine residues, Neclu_MT1 also contains a less common single C-terminal histidine residue. To better understand the role of this histidine residue in metal ion binding, for the first time, potentiometric pH titrations are applied, revealing insights into the protonation and metal ion binding processes. Additional studies with absorption and NMR spectroscopy complement the finding that while the histidine residue is not crucial for the overall metal binding capacity, it does serve as a ligand in the ZnII but not in the CdII form of the protein.
Subject(s)
Cadmium/chemistry , Histidine/chemistry , Hypocreales/chemistry , Metallothionein/chemistry , Zinc/chemistryABSTRACT
Labeling of long RNA molecules in a site-specific yet generally applicable manner is integral to many spectroscopic applications. Here we present a novel covalent labeling approach that is site-specific and scalable to long intricately folded RNAs. In this approach, a custom-designed DNA strand that hybridizes to the RNA guides a reactive group to target a preselected adenine residue. The functionalized nucleotide along with the concomitantly oxidized 3'-terminus can subsequently be conjugated to two different fluorophores via bio-orthogonal chemistry. We validate this modular labeling platform using a regulatory RNA of 275 nucleotides, the btuB riboswitch of Escherichia coli, demonstrate its general applicability by modifying a base within a duplex, and show its site-selectivity in targeting a pair of adjacent adenines. Native folding and function of the RNA is confirmed on the single-molecule level by using FRET as a sensor to visualize and characterize the conformational equilibrium of the riboswitch upon binding of its cofactor adenosylcobalamin. The presented labeling strategy overcomes size and site constraints that have hampered routine production of labeled RNA that are beyond 200 nt in length.
Subject(s)
DNA/chemistry , Escherichia coli/chemistry , RNA/chemistry , Riboswitch , Staining and Labeling/methods , Adenine/chemistry , Adenine/metabolism , Carbocyanines/chemistry , Cobamides/chemistry , Cobamides/metabolism , DNA/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Fluorescence Resonance Energy Transfer , Fluorescent Dyes/chemistry , Nucleic Acid Hybridization , Oligoribonucleotides/chemical synthesis , Oligoribonucleotides/chemistry , RNA/metabolism , RNA FoldingABSTRACT
Background: Patients with chronic critical limb-threatening ischemia (CLTI) are at high risk of amputation and death. Despite the general recommendation for revascularization in CTLI in the guidelines, the underlying evidence for such a recommendation is limited. The aim of our study was to assess the outcome of patients with CLTI depending on the use of revascularization in a retrospective real-world cohort. Patients and methods: Administrative data of the largest German Health insurance (BARMER GEK) were provided for all patients that were hospitalized for the treatment of CLTI Rutherford category (RF) 5 and 6 between 2009 and 2011. Patients were followed-up until December 31st, 2012 for limb amputation and death in relation to whether patients did (Rx +) or did not have (Rx -) revascularization during index-hospitalization. Results: We identified 15,314 patients with CLTI at RF5 (n = 6,908 (45.1%)) and RF6 (n = 8,406 (54.9%)), thereof 7,651 (50.0%) underwent revascularization (Rx +) and 7,663 (50.0%) were treated conservatively (Rx -). During follow-up (mean 647 days; 95% CI 640-654 days) limb amputation (46.5% Rx- vs. 40.6% Rx+, P < 0.001) and overall mortality (48.2% Rx- vs. 42.6% Rx+, P < 0.001) were significantly lower in the subgroup Rx+. Conclusions: In a real-world setting, only half of CLTI were revascularized during the in-hospital treatment. Though, revascularization was associated with significantly better observed short- and long-term outcome. These data do not allow causal conclusion due to lack of data on the underlying reason for applied or withheld revascularization and therefore may involve a relevant selection bias.
Subject(s)
Endovascular Procedures , Ischemia , Amputation, Surgical , Humans , Limb Salvage , Peripheral Arterial Disease , Retrospective Studies , Risk Factors , Time Factors , Treatment OutcomeABSTRACT
Life depends on metals. While carbon, in terms of abundance and versatility, is considered THE element of life, the vast variety and diversity of the chemistry taking place in living organisms could not be achieved without metal ions. More than twenty metals are found in the human body, most of them being essential, some beneficial, and for others it is still unknown what role they might fulfil in a living cell. Here we give a short introduction into the bioinorganic world of the periodic table, providing just a few examples of key metals for life and aiming to give a flavour to gain further insights into this exciting field of inorganic chemistry at the intersection to the life sciences.
ABSTRACT
Exploring the spatiotemporal dynamics of biomolecules on a single-molecule level requires innovative ways to make them spectroscopically visible. Fluorescence resonance energy transfer (FRET) uses a pair of organic dyes as reporters to measure distances along a predefined biomolecular reaction coordinate. For this nanoscopic ruler to work, the fluorescent labels need to be coupled onto the molecule of interest in a bioorthogonal and site-selective manner. Tagging large non-coding RNAs with single-nucleotide precision is an open challenge. Here we summarize current strategies in labeling riboswitches and ribozymes for fluorescence spectroscopy and FRET in particular. A special focus lies on our recently developed, DNA-guided approach that inserts two fluorophores through a stepwise process of templated functionality transfer and click chemistry.
Subject(s)
Fluorescence Resonance Energy Transfer , Click Chemistry , DNA , Fluorescent Dyes , RNAABSTRACT
The superfamily of metallothioneins (MTs) combines a diverse group of metalloproteins, sharing the characteristics of rather low molecular weight and high cysteine content. The latter provides MTs with the capability to coordinate thiophilic metal ions, in particular those with a d 10 electron configuration. The sub-family of plant MT3 proteins is only poorly characterized and there is a complete lack of three-dimensional structure information. Building upon our previous results on the Musa acuminata MT3 (musMT3) protein, the focus of the present work is to understand the metal cluster formation process, the role of the single histidine residue present in musMT3, and the metal ion binding affinity. We concentrate our efforts on the coordination of ZnII and CdII ions, using CoII as a spectroscopic probe for ZnII binding. The overall protein-fold is analysed with a combination of limited proteolytic digestion, mass spectrometry, and dynamic light scattering. Histidine coordination of metal ions is probed with extended X-ray absorption fine structure spectroscopy and CoII titration experiments. Initial experiments with isothermal titration calorimetry provide insights into the thermodynamics of metal ion binding.
Subject(s)
Cadmium/metabolism , Metallothionein/metabolism , Musa/chemistry , Plant Proteins/metabolism , Zinc/metabolism , Amino Acid Sequence , Binding Sites , Cobalt/metabolism , Coordination Complexes/chemistry , Histidine/metabolism , Hydrolysis , Metallothionein/chemistry , Metallothionein/genetics , Mutation , Peptide Fragments/chemistry , Peptide Fragments/genetics , Peptide Fragments/metabolism , Plant Proteins/chemistry , Plant Proteins/genetics , Protein BindingABSTRACT
BACKGROUND: Patients with diabetes concomitant to critical limb ischemia (CLI) represent a sub-group at particular risk. Objective of this analysis is to evaluate the actual impact of diabetes on treatment, outcome, and costs in a real-world scenario in Germany. METHODS: We obtained routine-data on 15,332 patients with CLI with tissue loss from the largest German health insurance, BARMER GEK from 2009 to 2011, including a follow-up until 2013. Patient data were analyzed regarding co-diagnosis with diabetes with respect to risk profiles, treatment strategy, in-hospital and long-term outcome including costs. RESULTS: Diabetic patients received less overall revascularizations in Rutherford grades 5 and 6 (Rutherford grade 5: 45.0 vs. 55.5%; Rutherford grade 6: 46.5 vs. 51.8; p < 0.001) and less vascular surgery (Rutherford grade 5: 13.4 vs. 23.4; Rutherford grade 6: 19.7 vs. 29.6; p < 0.001), however more often endovascular revascularization in Rutherford grade 6 (31.0 vs. 28.1; p = 0.004) compared to non-diabetic patients. Diabetes was associated with a higher observed ratio of infections (35.3 vs. 23.5% Rutherford grade 5; 44.3 vs. 27.4% Rutherford grade 6; p < 0.001) and in-hospital amputations (13.0 vs. 7.3% Rutherford grade 5; 47.5 vs. 36.7% Ruth6; p < 0.001). Diabetes further increased the risk for amputation during follow-up [Rutherford grade 5: HR 1.51 (1.38-1.67); Rutherford grade 6: HR 1.33 (1.25-1.41); p < 0.001], but not for death. CONCLUSIONS: Diabetes increases markedly the risk of amputation attended by higher costs in CLI patients with tissue loss (OR 1.67 at Rutherford 5, OR 1.53 at Rutherford 6; p < 0.001), but is associated with lower revascularizations. However, in Rutherford grades 5 and 6, concomitant diabetes does not further worsen the overall poor survival.