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2.
Am Heart J ; 272: 1-10, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38458372

RESUMO

BACKGROUND: The increasing burden of atrial fibrillation (AF) emphasizes the need to identify high-risk individuals for enrolment in clinical trials of AF screening and primary prevention. We aimed to develop prediction models to identify individuals at high-risk of AF across prediction horizons from 6-months to 10-years. METHODS: We used secondary-care linked primary care electronic health record data from individuals aged ≥30 years without known AF in the UK Clinical Practice Research Datalink-GOLD dataset between January 2, 1998 and November 30, 2018; randomly divided into derivation (80%) and validation (20%) datasets. Models were derived using logistic regression from known AF risk factors for incident AF in prediction periods of 6 months, 1-year, 2-years, 5-years, and 10-years. Performance was evaluated using in the validation dataset with bootstrap validation with 200 samples, and compared against the CHA2DS2-VASc and C2HEST scores. RESULTS: Of 2,081,139 individuals in the cohort (1,664,911 in the development dataset, 416,228 in the validation dataset), the mean age was 49.9 (SD 15.4), 50.7% were women, and 86.7% were white. New cases of AF were 7,386 (0.4%) within 6 months, 15,349 (0.7%) in 1 year, 38,487 (1.8%) in 5 years, and 79,997 (3.8%) by 10 years. Valvular heart disease and heart failure were the strongest predictors, and association of hypertension with AF increased at longer prediction horizons. The optimal risk models incorporated age, sex, ethnicity, and 8 comorbidities. The models demonstrated good-to-excellent discrimination and strong calibration across prediction horizons (AUROC, 95%CI, calibration slope: 6-months, 0.803, 0.789-0.821, 0.952; 1-year, 0.807, 0.794-0.819, 0.962; 2-years, 0.815, 0.807-0.823, 0.973; 5-years, 0.807, 0.803-0.812, 1.000; 10-years 0.780, 0.777-0.784, 1.010), and superior to the CHA2DS2-VASc and C2HEST scores. The models are available as a web-based FIND-AF calculator. CONCLUSIONS: The FIND-AF models demonstrate high discrimination and calibration across short- and long-term prediction horizons in 2 million individuals. Their utility to inform trial enrolment and clinical decisions for AF screening and primary prevention requires further study.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/complicações , Feminino , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Reino Unido/epidemiologia , Incidência , Fatores de Risco , Idoso , Adulto
3.
BMJ Open ; 13(12): e075196, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070890

RESUMO

INTRODUCTION: Atrial fibrillation (AF) is a major public health issue and there is rationale for the early diagnosis of AF before the first complication occurs. Previous AF screening research is limited by low yields of new cases and strokes prevented in the screened populations. For AF screening to be clinically and cost-effective, the efficiency of identification of newly diagnosed AF needs to be improved and the intervention offered may have to extend beyond oral anticoagulation for stroke prophylaxis. Previous prediction models for incident AF have been limited by their data sources and methodologies. METHODS AND ANALYSIS: We will investigate the application of random forest and multivariable logistic regression to predict incident AF within a 6-month prediction horizon, that is, a time-window consistent with conducting investigation for AF. The Clinical Practice Research Datalink (CPRD)-GOLD dataset will be used for derivation, and the Clalit Health Services (CHS) dataset will be used for international external geographical validation. Analyses will include metrics of prediction performance and clinical utility. We will create Kaplan-Meier plots for individuals identified as higher and lower predicted risk of AF and derive the cumulative incidence rate for non-AF cardio-renal-metabolic diseases and death over the longer term to establish how predicted AF risk is associated with a range of new non-AF disease states. ETHICS AND DISSEMINATION: Permission for CPRD-GOLD was obtained from CPRD (ref no: 19_076). The CPRD ethical approval committee approved the study. CHS Helsinki committee approval 21-0169 and data usage committee approval 901. The results will be submitted as a research paper for publication to a peer-reviewed journal and presented at peer-reviewed conferences. TRIAL REGISTRATION NUMBER: A systematic review to guide the overall project was registered on PROSPERO (registration number CRD42021245093). The study was registered on ClinicalTrials.gov (NCT05837364).


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/diagnóstico , Registros Eletrônicos de Saúde , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Incidência , Revisões Sistemáticas como Assunto
4.
Urology ; 182: 161-167, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37689247

RESUMO

OBJECTIVE: To understand the relationship between common urologic medications phosphodiesterase-5 inhibitors (PDE5i) and anticholinergics (AC) and risk of dementia onset in men who underwent different primary treatments for prostate cancer. MATERIALS AND METHODS: Patients (>50years) with prostate cancer (1998-2022) without Alzheimer's disease or related dementias were selected from Cancer of the Prostatic Strategic Urologic Research Endeavor Registry. Minimum medication use was 3months. Fine-Gray regression was performed to determine the association between medication exposure and dementia onset ≥12months after primary treatment in men matched on age, race, comorbid conditions, smoking, and type of clinical site, with competing risk of death. RESULTS: Among 5937 men (53% PDE5i; 14% AC), PDE5i users were younger (63 vs 70, P < .01) with less CAD, CVA, DM (all P < .01); AC users were older (68 vs 66, P < .01) with higher incidence of comorbidities (P < .01). Median months of use was 24.3 (IQR 12.1, 48.7) for PDE5i and 12.2 (IQR 6.1, 24.3) for AC users. Cumulative incidence of Alzheimer's disease or related dementias was 6.5% at 15years. PDE5i (P = .07) and AC (P = .06) were not associated with dementia regardless of primary treatment modality. CONCLUSION: In this retrospective cohort study, PDE5i and AC use do not appear independently associated with risk of dementia. Notably, our cohort was generally healthy and younger which may limit our ability to detect significance. We recommend prospective investigation into association between PDE5i and dementia and advise continued judicious stewardship of AC in older patient populations.


Assuntos
Doença de Alzheimer , Neoplasias da Próstata , Masculino , Humanos , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/induzido quimicamente , Estudos Retrospectivos , Estudos Prospectivos , Neoplasias da Próstata/complicações , Neoplasias da Próstata/tratamento farmacológico , Próstata , Inibidores da Fosfodiesterase 5/uso terapêutico
5.
Eur Heart J ; 44(42): 4422-4431, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37624589

RESUMO

BACKGROUND AND AIMS: Reports of outcomes after atrial fibrillation (AF) diagnosis are conflicting. The aim of this study was to investigate mortality and hospitalization rates following AF diagnosis over time, by cause and by patient features. METHODS: Individuals aged ≥16 years with a first diagnosis of AF were identified from the UK Clinical Practice Research Datalink-GOLD dataset from 1 January 2001, to 31 December 2017. The primary outcomes were all-cause and cause-specific mortality and hospitalization at 1 year following diagnosis. Poisson regression was used to calculate rate ratios (RRs) for mortality and incidence RRs (IRRs) for hospitalization and 95% confidence intervals (CIs) comparing 2001/02 and 2016/17, adjusted for age, sex, region, socio-economic status, and 18 major comorbidities. RESULTS: Of 72 412 participants, mean (standard deviation) age was 75.6 (12.4) years, and 44 762 (61.8%) had ≥3 comorbidities. All-cause mortality declined (RR 2016/17 vs. 2001/02 0.72; 95% CI 0.65-0.80), with large declines for cardiovascular (RR 0.46; 95% CI 0.37-0.58) and cerebrovascular mortality (RR 0.41; 95% CI 0.29-0.60) but not for non-cardio/cerebrovascular causes of death (RR 0.91; 95% CI 0.80-1.04). In 2016/17, deaths caused from dementia (67, 8.0%), outstripped deaths from acute myocardial infarction, heart failure, and acute stroke combined (56, 6.7%, P < .001). Overall hospitalization rates increased (IRR 2016/17 vs. 2001/02 1.17; 95% CI, 1.13-1.22), especially for non-cardio/cerebrovascular causes (IRR 1.42; 95% CI 1.39-1.45). Older, more deprived, and hospital-diagnosed AF patients experienced higher event rates. CONCLUSIONS: After AF diagnosis, cardio/cerebrovascular mortality and hospitalization has declined, whilst hospitalization for non-cardio/cerebrovascular disease has increased.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/epidemiologia , Causas de Morte , Acidente Vascular Cerebral/epidemiologia , Comorbidade , Hospitalização , Fatores de Risco
6.
Urology ; 180: 242-248, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37442296

RESUMO

OBJECTIVE: To characterize the incidence of stress urinary incontinence (SUI) after radical prostatectomy (RP), its treatment, and impact on quality of life (QoL) and work status 1year after RP. MATERIALS AND METHODS: Prostate cancer patients treated by RP (1998-2016) were selected from CaPSURE. SUI was defined as any pads per day (ppd) 1 year after RP. SUI procedures were tracked by CPT codes (sling and artificial sphincter). Patients reported work status (full-time, part-time, unpaid), UCLA PCa Index urinary function (UF) and bother (UB) and SF36 Index physical function (PF). Associations of incontinence with UF, UB, and PF and work status changes were assessed (ANOVA). Lifetable estimates and Cox proportional hazards regression evaluated risk of undergoing SUI procedures. RESULTS: 664/2989 (22%) men treated with RP reported SUI at 1 year. More men with SUI had ≥GG2, intermediate to high-risk disease and non-nerve-sparing surgery (all P < .01). Cumulative incidence of SUI procedures was 1.4% at 10years after RP. Age (HR 2.68 per 10years, 95% CI 1.41-5.08) and number of ppd at 1 year (HR 3.20, 95% CI 2.27-4.50) were associated with undergoing SUI procedures. UF declined at 1year after RP, while UB and PF remained stable. UF, UB, and PF were inversely associated with number of ppd (all P < .01). Change in work status was not associated with incontinence or QoL scores. CONCLUSION: Incontinence affected QoL without impacting work status, suggesting that men with SUI after RP may continue working and go under-treated despite impact on QoL.

7.
BMC Genom Data ; 24(1): 26, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37131148

RESUMO

HostSeq was launched in April 2020 as a national initiative to integrate whole genome sequencing data from 10,000 Canadians infected with SARS-CoV-2 with clinical information related to their disease experience. The mandate of HostSeq is to support the Canadian and international research communities in their efforts to understand the risk factors for disease and associated health outcomes and support the development of interventions such as vaccines and therapeutics. HostSeq is a collaboration among 13 independent epidemiological studies of SARS-CoV-2 across five provinces in Canada. Aggregated data collected by HostSeq are made available to the public through two data portals: a phenotype portal showing summaries of major variables and their distributions, and a variant search portal enabling queries in a genomic region. Individual-level data is available to the global research community for health research through a Data Access Agreement and Data Access Compliance Office approval. Here we provide an overview of the collective project design along with summary level information for HostSeq. We highlight several statistical considerations for researchers using the HostSeq platform regarding data aggregation, sampling mechanism, covariate adjustment, and X chromosome analysis. In addition to serving as a rich data source, the diversity of study designs, sample sizes, and research objectives among the participating studies provides unique opportunities for the research community.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Canadá/epidemiologia , Genômica , Sequenciamento Completo do Genoma
8.
Life (Basel) ; 14(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38255681

RESUMO

Natural chiral amino acids typically adopt an L structural configuration. While a preference for specific molecular chiralities is observed throughout biology and cellular chemistry, the origins of this preference are unclear. In a previous report the origin of enantiomeric selectivity was analyzed in terms of an "RNA World" model, and a pathway to a chiral preference for d-ribose was proposed based on the autocatalytic transformation of glyceraldehyde as a precursor to the formation of sugars. Metal-ion-promoted catalysis allows the parity non-conserving (PNC) weak nuclear interaction to influence the chirality of a nascent chiral carbon center. Since the PNC effect is the only natural property with an inherent handedness, it is an obvious candidate to influence enantiomeric preference from a catalytic reaction performed over geologically relevant time scales. The PNC influence requires and emphasizes the important role of catalytic metal ions in primordial chemistry. In this study, the impact of geologically available divalent calcium and higher Z alkaline earth elements are examined as mediators of chiral preference. Detailed calculations of the magnitude of the effect are presented, including the influence of time, temperature, pH, and metal ion identity. It is concluded that metal ions can direct chiral preference for amino acid synthesis via a metal-promoted autocatalytic Strecker reaction within a relatively short geological timeframe, thereby providing a pool of l-amino acids for catalytic chemistry evolving either from an RNA-world model of molecular evolution or alternative pathways to protein synthesis.

9.
Int J Mol Sci ; 23(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36430622

RESUMO

Antibiotic resistance demands innovative strategies and therapies. The pairs of antimicrobial peptides tested in this work show broad-spectrum synergy and are capable of interacting with diverse bacterial membranes. In most cases, the ATCUN motif enhanced the activity of peptides tested in combination. Our studies also show CP10A to be a multifaceted peptide, displaying both cell membrane and intracellular activity and acting as a chameleon, improving the activity of other peptides as needed. The results of the synergy experiments demonstrate the importance of varied modes of action and how these changes can affect the ability to combat pathogens, while also illustrating the value of the metal-binding domain in enhancing the activity of antimicrobial peptides in combination.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Peptídeos Catiônicos Antimicrobianos/química , Motivos de Aminoácidos , Cobre/química , Membrana Celular/metabolismo
10.
Nat Commun ; 13(1): 4339, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896548

RESUMO

In eukaryotes, iron-sulfur clusters are essential cofactors for numerous physiological processes, but these clusters are primarily biosynthesized in mitochondria. Previous studies suggest mitochondrial ABCB7-type exporters are involved in maturation of cytosolic iron-sulfur proteins. However, the molecular mechanism for how the ABCB7-type exporters participate in this process remains elusive. Here, we report a series of cryo-electron microscopy structures of a eukaryotic homolog of human ABCB7, CtAtm1, determined at average resolutions ranging from 2.8 to 3.2 Å, complemented by functional characterization and molecular docking in silico. We propose that CtAtm1 accepts delivery from glutathione-complexed iron-sulfur clusters. A partially occluded state links cargo-binding to residues at the mitochondrial matrix interface that line a positively charged cavity, while the binding region becomes internalized and is partially divided in an early occluded state. Collectively, our findings substantially increase the understanding of the transport mechanism of eukaryotic ABCB7-type proteins.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas Ferro-Enxofre , Proteínas Mitocondriais , Microscopia Crioeletrônica , Humanos , Ferro/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Simulação de Acoplamento Molecular , Enxofre/metabolismo
11.
Biochimie ; 192: 51-62, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34582998

RESUMO

Iron-sulfur clusters are ubiquitous cofactors required for various essential metabolic processes. Conservation of proteins required for their biosynthesis and trafficking allows for simple bacteria to be used as models to aid in exploring these complex pathways in higher organisms. Cyanobacteria are among the most investigated organisms for these processes, as they are unicellular and can survive under photoautotrophic and heterotrophic conditions. Herein, we report the potential role of Synechocystis PCC6803 NifU (now named SyNfu) as the principal scaffold protein required for iron-sulfur cluster biosynthesis in that organism. SyNfu is a well-folded protein with distinct secondary structural elements, as evidenced by circular dichroism and a well-dispersed pattern of 1H-15N HSQC NMR peaks, and readily reconstitutes as a [2Fe-2S] dimeric protein complex. Cluster exchange experiments show that glutathione can extract the cluster from holo-SyNfu, but the transfer is unidirectional. We also confirm the ability of SyNfu to transfer cluster to both human ferredoxin 1 and ferredoxin 2, while also demonstrating the capacity to deliver cluster to both monothiol glutaredoxin 3 and dithiol glutaredoxin 2. This evidence supports the hypothesis that SyNfu indeed serves as the main scaffold protein in Synechocystis, as it has been shown to be the only protein required for viability in the absence of photoautotrophic conditions. Similar to other NFU-type cluster donors and other scaffold and carrier proteins, such as ISCU, SyNfu is shown by DSC to be structurally less stable than regular protein donors, while retaining a relatively well-defined tertiary structure as represented by 1H-15N HSQC NMR experiments.


Assuntos
Proteínas de Bactérias/química , Proteínas Ferro-Enxofre/química , Ressonância Magnética Nuclear Biomolecular , Synechocystis/química , Proteínas de Bactérias/metabolismo , Humanos , Proteínas Ferro-Enxofre/metabolismo , Synechocystis/metabolismo
12.
Metallomics ; 13(10)2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34543426

RESUMO

Human aspartyl/asparaginyl beta-hydroxylase (HAAH) is a member of the superfamily of nonheme Fe2+/α-ketoglutarate (αKG) dependent oxygenase enzymes with a noncanonical active site. HAAH hydroxylates epidermal growth factor (EGF) like domains to form the ß-hydroxylated product from substrate asparagine or aspartic acid and has been suggested to have a negative impact in a variety of cancers. In addition to iron, HAAH also binds divalent calcium, although the role of the latter is not understood. Herein, the metal binding chemistry and influence on enzyme stability and activity have been evaluated by a combined biochemical and biophysical approach. Metal binding parameters for the HAAH active site were determined by use of isothermal titration calorimetry, demonstrating a high-affinity regulatory binding site for Ca2+ in the catalytic domain in addition to the catalytic Fe2+ cofactor. We have analyzed various active site derivatives, utilizing LC-MS and a new HPLC technique to determine the role of metal binding and the second coordination sphere in enzyme activity, discovering a previously unreported residue as vital for HAAH turnover. This analysis of the in vitro biochemical function of HAAH furthers the understanding of its importance to cellular biochemistry and metabolic pathways.


Assuntos
Isoenzimas/metabolismo , Oxigenases de Função Mista/metabolismo , Cálcio/metabolismo , Calorimetria/métodos , Domínio Catalítico , Cromatografia Líquida de Alta Pressão/métodos , Compostos Ferrosos/metabolismo , Humanos , Isoenzimas/química , Cinética , Oxigenases de Função Mista/química , Modelos Moleculares , Fenil-Hidrazinas/metabolismo , Espectrometria de Massas em Tandem/métodos
13.
Rev Sci Instrum ; 92(7): 075103, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340426

RESUMO

X-ray films remain a key asset for high-resolution x-ray spectral imaging in high-energy-density experiments conducted at the National Ignition Facility (NIF). The soft x-ray Opacity Spectrometer (OpSpec) fielded at the NIF has an elliptically shaped crystal design that measures x rays in the 900-2100 eV range and currently uses an image plate as the detecting medium. However, Agfa D4 and D3sc x-ray films' higher spatial resolution provides increased spectral resolution to the data over the IP-TR image plates, driving the desire for regular use of x-ray film as a detecting medium. The calibration of Agfa D4 x-ray film for use in the OpSpec is communicated here. These calibration efforts are vital to the accuracy of the NIF opacity measurements and are conducted in a previously un-studied x-ray energy range under a new film development protocol required by NIF. The absolute response of Agfa D4 x-ray film from 705 to 4620 eV has been measured using the Nevada National Security Site Manson x-ray source. A broader range of energies was selected to compare results with previously published data. The measurements were taken using selected anodes, filters, and applied voltages to produce well-defined energy lines.

14.
Metallomics ; 13(8)2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34283245

RESUMO

Human aspartyl (asparaginyl) ß-hydroxylase (HAAH), a unique iron and 2-oxoglutarate dependent oxygenase, has shown increased importance as a suspected oncogenic protein. HAAH and its associated mRNA are upregulated in a wide variety of cancer types, however, the current role of HAAH in the malignant transformation of cells is unknown. HAAH is suspected to play an important role in NOTCH signaling via selective hydroxylation of aspartic acid and asparagine residues of epidermal growth factor (EGF)-like domains. HAAH hydroxylation also potentially mediates calcium signaling and oxygen sensing. In this review, we summarize the current state of understanding of the biochemistry and chemical biology of this enzyme, identify key differences from other family members, outline its broader intra- and extra-cellular roles, and identify the most promising areas for future research efforts.


Assuntos
Asparagina/metabolismo , Ácido Aspártico/metabolismo , Oxigenases de Função Mista/metabolismo , Humanos , Hidroxilação
15.
Metallomics ; 13(5)2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33770183

RESUMO

Glutathione is the major thiol-containing species in both prokaryotes and eukaryotes and plays a wide variety of roles, including detoxification of metals by sequestration, reduction, and efflux. ABC transporters such as MRP1 and MRP2 detoxify the cell from certain metals by exporting the cations as a metal-glutathione complex. The ability of the bacterial Atm1 protein to efflux metal-glutathione complexes appears to have evolved over time to become the ABCB7 transporter in mammals, located in the inner mitochondrial membrane. No longer needed for the role of cellular detoxification, ABCB7 appears to be used to transport glutathione-coordinated iron-sulfur clusters from mitochondria to the cytosol.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Complexos de Coordenação/metabolismo , Glutationa/química , Metais/química , Transportadores de Cassetes de Ligação de ATP/química , Animais , Complexos de Coordenação/química , Humanos
16.
Metallomics ; 13(4)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33693876

RESUMO

Iron-sulfur (Fe-S) cluster biosynthesis involves the action of a variety of functionally distinct proteins, most of which are evolutionarily conserved. Mutations in these Fe-S scaffold and trafficking proteins can cause diseases such as multiple mitochondrial dysfunctions syndrome (MMDS), sideroblastic anemia, and mitochondrial encephalopathy. Herein, we investigate the effect of Ile67Asn substitution in the BOLA3 protein that results in the MMDS2 phenotype. Although the exact functional role of BOLA3 in Fe-S cluster biosynthesis is not known, the [2Fe-2S]-bridged complex of BOLA3 with GLRX5, another Fe-S protein, has been proposed as a viable intermediary cluster carrier to downstream targets. Our investigations reveal that the Ile67Asn substitution impairs the ability of BOLA3 to bind its physiological partner GLRX5, resulting in a failure to form the [2Fe-2S]-bridged complex. Although no drastic structural change in BOLA3 arises from the substitution, as evidenced by wild-type and mutant BOLA3 1H-15N HSQC and ion mobility native mass spectrometry experiments, this substitution appears to influence cluster reconstitution on downstream proteins leading to the disease phenotype. By contrast, substituted derivatives of the holo homodimeric form of BOLA3 are formed and remain active toward cluster exchange.


Assuntos
Asparagina/química , Glutarredoxinas/metabolismo , Isoleucina/química , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutação , Asparagina/genética , Asparagina/metabolismo , Glutarredoxinas/química , Glutarredoxinas/genética , Humanos , Isoleucina/genética , Isoleucina/metabolismo , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Proteínas Mitocondriais/química , Mutagênese Sítio-Dirigida , Conformação Proteica , Multimerização Proteica
17.
Int J Mol Sci ; 22(4)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562493

RESUMO

Lipoyl synthase (LIAS) is an iron-sulfur cluster protein and a member of the radical S-adenosylmethionine (SAM) superfamily that catalyzes the final step of lipoic acid biosynthesis. The enzyme contains two [4Fe-4S] centers (reducing and auxiliary clusters) that promote radical formation and sulfur transfer, respectively. Most information concerning LIAS and its mechanism has been determined from prokaryotic enzymes. Herein, we detail the expression, isolation, and characterization of human LIAS, its reactivity, and evaluation of natural iron-sulfur (Fe-S) cluster reconstitution mechanisms. Cluster donation by a number of possible cluster donor proteins and heterodimeric complexes has been evaluated. [2Fe-2S]-cluster-bound forms of human ISCU and ISCA2 were found capable of reconstituting human LIAS, such that complete product turnover was enabled for LIAS, as monitored via a liquid chromatography-mass spectrometry (LC-MS) assay. Electron paramagnetic resonance (EPR) studies of native LIAS and substituted derivatives that lacked the ability to bind one or the other of LIAS's two [4Fe-4S] clusters revealed a likely order of cluster addition, with the auxiliary cluster preceding the reducing [4Fe-4S] center. These results detail the trafficking of Fe-S clusters in human cells and highlight differences with respect to bacterial LIAS analogs. Likely in vivo Fe-S cluster donors to LIAS are identified, with possible connections to human disease states, and a mechanistic ordering of [4Fe-4S] cluster reconstitution is evident.


Assuntos
Proteínas Ferro-Enxofre/metabolismo , Sulfurtransferases/metabolismo , Substituição de Aminoácidos , Biocatálise , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Técnicas In Vitro , Ferro/metabolismo , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/genética , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise Espectral , Enxofre/metabolismo , Sulfurtransferases/química , Sulfurtransferases/genética , Ácido Tióctico/biossíntese
18.
Heart ; 107(1): 47-53, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33122302

RESUMO

OBJECTIVE: To assess temporal clinical and budget impacts of changes in atrial fibrillation (AF)-related prescribing in England. METHODS: Data on AF prevalence, AF-related stroke incidence and prescribing for all National Health Service general practices, hospitals and registered patients with hospitalised AF-related stroke in England were obtained from national databases. Stroke care costs were based on published data. We compared changes in oral anticoagulation prescribing (warfarin or direct oral anticoagulants (DOACs)), incidence of hospitalised AF-related stroke, and associated overall and per-patient costs in the periods January 2011-June 2014 and July 2014-December 2017. RESULTS: Between 2011-2014 and 2014-2017, recipients of oral anticoagulation for AF increased by 86.5% from 1 381 170 to 2 575 669. The number of patients prescribed warfarin grew by 16.1% from 1 313 544 to 1 525 674 and those taking DOACs by 1452.7% from 67 626 to 1 049 995. Prescribed items increased by 5.9% for warfarin (95% CI 2.9% to 8.9%) but by 2004.8% for DOACs (95% CI 1848.8% to 2160.7%). Oral anticoagulation prescription cost rose overall by 781.2%, from £87 313 310 to £769 444 028, (£733,466,204 with warfarin monitoring) and per patient by 50.7%, from £293 to £442, giving an incremental cost of £149. Nevertheless, as AF-related stroke incidence fell by 11.3% (95% CI -11.5% to -11.1%) from 86 467 in 2011-2014 to 76 730 in 2014-2017 with adjustment for AF prevalence, the overall per-patient cost reduced from £1129 to £840, giving an incremental per-patient saving of £289. CONCLUSIONS: Despite nearly one million additional DOAC prescriptions and substantial associated spending in the latter part of this study, the decline in AF-related stroke led to incremental savings at the national level.


Assuntos
Anticoagulantes/economia , Anticoagulantes/uso terapêutico , Fibrilação Atrial/complicações , Orçamentos , Inibidores do Fator Xa/economia , Inibidores do Fator Xa/uso terapêutico , Custos de Cuidados de Saúde , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/prevenção & controle , Varfarina/economia , Varfarina/uso terapêutico , Inglaterra , Humanos , Estudos Prospectivos , Acidente Vascular Cerebral/etiologia
19.
Arch Biochem Biophys ; 697: 108661, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33157103

RESUMO

Iron-sulfur cluster proteins play key roles in a multitude of cellular processes. Iron-sulfur cofactors are assembled primarily in mitochondria and are then exported to the cytosol by use of an ABCB7 transporter. It has been shown that the yeast mitochondrial transporter Atm1 can export glutathione-coordinated iron-sulfur clusters, [2Fe-2S](SG)4, providing a source of cluster units for cytosolic iron-sulfur cluster assembly systems. This pathway is consistent with the endosymbiotic model of mitochondrial evolution where homologous bacterial heavy metal transporters, utilizing metal glutathione adducts, were adapted for use in eukaryotic mitochondria. Herein, the basis for endosymbiotic evolution of the human cluster export protein (ABCB7) is developed through a BLAST analysis of transporters from ancient proteobacteria. In addition, a functional comparison of native human protein, versus a disease-causing mutant, demonstrates a key role for residue E433 in promoting cluster transport. Dysfunction in mitochondrial export of Fe-S clusters is a likely cause of the disease condition X-linked sideroblastic anemia.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Evolução Molecular , Mutação , Transportadores de Cassetes de Ligação de ATP/química , Adenosina Trifosfatases/metabolismo , Humanos , Cinética , Modelos Moleculares , Conformação Proteica
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