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1.
ESC Heart Fail ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38803153

RESUMO

AIMS: The prevalence of iron deficiency (ID) in newly diagnosed heart failure (HF) and the progression of ID in patients after initiation of HF therapy are unknown. We aimed to describe the natural trajectory of ID in patients with new onset HF during the first year after HF diagnosis, assessing associations between ID, clinical factors, and quality of life (QoL). METHODS AND RESULTS: A prospective cohort of patients with new onset HF in hospitals or outpatient clinics at five major hospitals in Stockholm, Sweden, during 2015-2018 were analysed with clinical assessment, electrocardiogram, blood samples including iron levels, Minnesota living with heart failure questionnaire (MLHFQ), and echocardiogram at baseline and after 12 months. Of 547 patients with new-onset HF, 482 (88%) had complete iron data at baseline. Mean age was 70 years (interquartile range 61-77) and 311 (65%) were men; 55% of patients had ejection fraction (EF) ≤ 40%, 19% had EF 41-49%, and 26% had HF with preserved EF (HFpEF). At baseline, 163 patients (34%) had ID defined as ferritin <100 µg/L or ferritin 100-299 µg/L and transferrin saturation <20%. After 12 months of follow-up, 119 (32%) had ID of the 368 patients who had complete iron data both at baseline and after 12 months and did not receive intravenous (i.v.) iron during follow-up. During the first year after HF diagnosis, 19% had persistent ID, 13% developed ID, 11% resolved ID, and 57% never had ID, consequently 24% changed their classification. Anaemia at baseline was the strongest independent predictor of ID 1 year after diagnosis [odds ratio (OR) 3.91, 95% confidence interval (CI) 1.88-8.13, P < 0.001], followed by HF hospitalization (OR 2.21, 95% CI 1.24-3.95, P < 0.01), female sex (OR 2.04, 95% CI 1.25-3.32, P < 0.01), HFpEF (OR 1.96, 95% CI 1.13-3.39, P < 0.05), and diabetes mellitus (OR 1.92, 95% CI 1.06-3.48, P < 0.05). ID was associated with low QoL at baseline (MLHFQ score mean difference 7.4 points, 95% CI 3.1-11.7, P < 0.001), but not at follow-up. CONCLUSIONS: About one third of patients with new onset HF had ID both at the time of HF diagnosis and after 1 year, though a quarter of the patients changed their ID status. Patients with anaemia, HF hospitalization, female gender, HFpEF, or diabetes mellitus at baseline were more likely to have ID after 1 year implying that these should be carefully screened for ID to find those in need of i.v. iron treatment.

2.
Sci Rep ; 14(1): 5811, 2024 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461325

RESUMO

New or mild heart failure (HF) is mainly caused by left ventricular dysfunction. We hypothesised that gene expression differ between the left (LV) and right ventricle (RV) and secondly by type of LV dysfunction. We compared gene expression through myocardial biopsies from LV and RV of patients undergoing elective coronary bypass surgery (CABG). Patients were categorised based on LV ejection fraction (EF), diastolic function and NT-proBNP into pEF (preserved; LVEF ≥ 45%), rEF (reduced; LVEF < 45%) or normal LV function. Principal component analysis of gene expression displayed two clusters corresponding to LV and RV. Up-regulated genes in LV included natriuretic peptides NPPA and NPPB, transcription factors/coactivators STAT4 and VGLL2, ion channel related HCN2 and LRRC38 associated with cardiac muscle contraction, cytoskeleton, and cellular component movement. Patients with pEF phenotype versus normal differed in gene expression predominantly in LV, supporting that diastolic dysfunction and structural changes reflect early LV disease in pEF. DKK2 was overexpressed in LV of HFpEF phenotype, potentially leading to lower expression levels of ß-catenin, α-SMA (smooth muscle actin), and enhanced apoptosis, and could be a possible factor in the development of HFpEF. CXCL14 was down-regulated in both pEF and rEF, and may play a role to promote development of HF.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/genética , Ventrículos do Coração , Volume Sistólico/fisiologia , Ecocardiografia , Perfilação da Expressão Gênica , Biópsia , Função Ventricular Esquerda
3.
Front Cardiovasc Med ; 9: 952974, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330003

RESUMO

Aims: Extracellular vesicles (EVs) were investigated as potential biomarkers associated with heart failure (HF) pathophysiology in patients undergoing elective coronary artery bypass surgery characterized by HF phenotype. Materials and methods: Patients with preoperative proxy-diagnoses of HF types i.e., preserved (HFpEF; n = 19) or reduced ejection fraction (HFrEF; n = 20) were studied and compared to patients with normal left ventricular function (n = 42). EVs in plasma samples collected from the coronary sinus, an arterial line, and from the right atrium were analyzed by flow cytometry. We studied EVs of presumed cardiomyocyte origin [EVs exposing Connexin-43 + Caveolin-3 (Con43 + Cav3) and Connexin-43 + Troponin T (Con43 + TnT)], of endothelial origin [EVs exposing VE-Cadherin (VE-Cad)] and EVs exposing inflammatory markers [myeloperoxidase (MPO) or pentraxin3 (PTX3)]. Results: Median concentrations of EVs exposing Con43 + TnT and Con43 + Cav3 were approximately five to six times higher in coronary sinus compared to radial artery indicative of cardiac release. Patients with HFrEF had high trans-coronary gradients of both Con43 + TnT and Con43 + Cav3 EVs, whereas HFpEF had elevated gradients of Con43 + Cav3 EVs but lower gradients of Con43 + TnT. Coronary sinus concentrations of both Con43 + TnT and Con43 + Cav3 correlated significantly with echocardiographic and laboratory measures of HF. MPO-EV concentrations were around two times higher in the right atrium compared to the coronary sinus, and slightly higher in HFpEF than in HFrEF. EV concentrations of endothelial origin (VE-Cad) were similar in all three patient groups. Conclusion: Con43 + TnT and Con43 + Cav3 EVs are released over the heart indicating cardiomyocyte origin. In HFrEF the EV release profile is indicative of myocardial injury and myocardial stress with elevated trans-coronary gradients of both Con43 + TnT and Con43 + Cav3 EVs, whereas in HFpEF the profile indicates myocardial stress with less myocardial injury.

4.
ESC Heart Fail ; 9(4): 2125-2138, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35403374

RESUMO

AIM: We present the baseline characteristics of the PREFERS Stockholm epidemiological study on the natural history and course of new onset heart failure (HF) aiming to improve phenotyping focusing on HF with preserved left ventricular ejection fraction (HFpEF) pathophysiology. METHODS AND RESULTS: New onset HF patients diagnosed in hospital or at outpatient HF clinics were included at five Stockholm hospitals 2015-2018 and characterized by N-terminal pro brain natriuretic peptide (NT-proBNP), biomarkers, echocardiography, and cardiac magnetic resonance imaging (subset). HFpEF [left ventricular ejection fraction (LVEF) ≥ 50%] was compared with HF with mildly reduced LVEF (HFmrEF; LVEF 41-49%) and with HF with reduced LVEF (HFrEF; LVEF ≤ 40%). We included 547 patients whereof HFpEF (n = 137; 25%), HFmrEF (n = 61; 11%), and HFrEF (n = 349; 64%). HFpEF patients were older (76; 70-81 years; median; interquartile range) than HFrEF (67; 58-74; P < 0.001), more often women (49% vs. 30%; P < 0.001), and had significantly higher comorbidity burden. They more often had atrial fibrillation, hypertension, and renal dysfunction. NT-proBNP was lower in HFpEF (896; 462-1645 ng/L) than in HFrEF (1160; 563-2370; P = 0.005). In HFpEF, left ventricular (LV) diameters and volumes were smaller (P < 0.001) and septal and posterior wall thickness and relative wall thickness higher (P < 0.001). E/é ≥ 14 was present in 26% of HFpEF vs. 32% of HFrEF (P = 0.017) and left atrial volume index > 34 mL/m2 in 57% vs. 61% (P = 0.040). HFmrEF patients were intermediary between HFpEF and HFrEF for LV mass, LV volumes, and RV volumes but had the highest proportion of left ventricular hypertrophy and the lowest proportion of elevated E/é. CONCLUSIONS: Phenotype data in new onset HF patients recruited in a broad clinical setting showed that 25% had HFpEF, were older, more often women, and had greater comorbidity burden. PREFERS is well suited to further explore biomarker and imaging components of HFpEF pathophysiology and may contribute to the emerging knowledge of HF epidemiology. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03671122.


Assuntos
Insuficiência Cardíaca , Biomarcadores , Ecocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Prognóstico , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia
5.
J Card Fail ; 26(12): 1050-1059, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32750486

RESUMO

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) are associated with metabolic derangements, which may have different pathophysiological implications. METHODS AND RESULTS: In new-onset HFpEF (EF of ≥50%, n = 46) and HFrEF (EF of <40%, n = 75) patients, 109 endogenous plasma metabolites including amino acids, phospholipids and acylcarnitines were assessed using targeted metabolomics. Differentially altered metabolites and associations with clinical characteristics were explored. Patients with HFpEF were older, more often female with hypertension, atrial fibrillation, and diabetes compared with patients with HFrEF. Patients with HFpEF displayed higher levels of hydroxyproline and symmetric dimethyl arginine, alanine, cystine, and kynurenine reflecting fibrosis, inflammation and oxidative stress. Serine, cGMP, cAMP, l-carnitine, lysophophatidylcholine (18:2), lactate, and arginine were lower compared with patients with HFrEF. In patients with HFpEF with diabetes, kynurenine was higher (P = .014) and arginine lower (P = .014) vs patients with no diabetes, but did not differ with diabetes status in HFrEF. Decreasing kynurenine was associated with higher eGFR only in HFpEF (Pinteraction = .020). CONCLUSIONS: Patients with new-onset HFpEF compared with patients with new-onset HFrEF display a different metabolic profile associated with comorbidities, such as diabetes and kidney dysfunction. HFpEF is associated with indices of increased inflammation and oxidative stress, impaired lipid metabolism, increased collagen synthesis, and downregulated nitric oxide signaling. Together, these findings suggest a more predominant systemic microvascular endothelial dysfunction and inflammation linked to increased fibrosis in HFpEF compared with HFrEF. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT03671122 https://clinicaltrials.gov.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Feminino , Humanos , Metabolômica , Prognóstico , Volume Sistólico
6.
J Card Fail ; 26(5): 440-443, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32165346

RESUMO

BACKGROUND: Iron deficiency (ID) is common in patients with chronic heart failure (CHF), but the underlying causes are not fully understood. We investigated whether ID is associated with decreased iron absorption in patients with CHF. METHODS AND RESULTS: We performed an oral iron-absorption test in 30 patients and 12 controls. The patients had CHF with reduced (n = 15) or preserved (n = 15) ejection fraction and ID, defined as s-ferritin < 100 µg/L, or s-ferritin 100-299 µg/L and transferrin saturation < 20%. The controls had no HF or ID and were of similar age and gender. Blood samples were taken before and 2 hours after ingestion of 100 mg ferroglycin sulphate. The primary endpoint was the delta plasma iron at 2 hours. The delta plasma iron was higher in the group with HF than in the control group (median increase 83.8 [61.5;128.5] µg/dL in HF vs 47.5 [30.7;61.5] µg/dL in controls, P = 0.001), indicating increased iron absorption. There was no significant difference between the groups with preserved or reduced ejection fraction (P = 0.46). CONCLUSION: We found increased iron absorption in patients with CHF and ID compared to controls without ID and HF, indicating that reduced iron absorption is not a primary cause of the high prevalence of ID in patients with CHF. CLINICAL TRIAL REGISTRATION: EudraCT 2017-000158-21.


Assuntos
Anemia Ferropriva , Insuficiência Cardíaca , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/epidemiologia , Doença Crônica , Ferritinas , Insuficiência Cardíaca/epidemiologia , Humanos , Ferro
7.
Sci Rep ; 9(1): 3179, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816197

RESUMO

Heart failure affects 2-3% of adult Western population. Prevalence of heart failure with preserved left ventricular (LV) ejection fraction (HFpEF) increases. Studies suggest HFpEF patients to have altered myocardial structure and functional changes such as incomplete relaxation and increased cardiac stiffness. We hypothesised that patients undergoing elective coronary bypass surgery (CABG) with HFpEF characteristics would show distinctive gene expression compared to patients with normal LV physiology. Myocardial biopsies for mRNA expression analysis were obtained from sixteen patients with LV ejection fraction ≥45%. Five out of 16 patients (31%) had echocardiographic characteristics and increased NTproBNP levels indicative of HFpEF and this group was used as HFpEF proxy, while 11 patients had Normal LV physiology. Utilising principal component analysis, the gene expression data clustered into two groups, corresponding to HFpEF proxy and Normal physiology, and 743 differentially expressed genes were identified. The associated top biological functions were cardiac muscle contraction, oxidative phosphorylation, cellular remodelling and matrix organisation. Our results also indicate that upstream regulatory events, including inhibition of transcription factors STAT4, SRF and TP53, and activation of transcription repressors HEY2 and KDM5A, could provide explanatory mechanisms to observed gene expression differences and ultimately cardiac dysfunction in the HFpEF proxy group.


Assuntos
Insuficiência Cardíaca/genética , Miocárdio/metabolismo , Transcriptoma/genética , Função Ventricular Esquerda/genética , Idoso , Idoso de 80 Anos ou mais , Biópsia , Diástole , Ecocardiografia , Feminino , Regulação da Expressão Gênica/genética , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/genética , Miocárdio/patologia , Volume Sistólico/genética
8.
Eur J Heart Fail ; 18(10): 1287-1297, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27384611

RESUMO

AIMS: Heart failure (HF) with preserved (HFpEF) or reduced (HFrEF) ejection fraction is associated with poor prognosis and quality of life. While the incidence of HFrEF is declining and HF treatment is effective, HFpEF is increasing, with no established therapy. PREFERS Stockholm is an epidemiological study with the aim of improving clinical care and research in HF and to find new targets for drug treatment in HFpEF (https://internwebben.ki.se/sites/default/files/20150605_4d_research_appendix_final.pdf). METHODS: Patients with new-onset HF (n = 2000) will be characterized at baseline and after 1-year follow-up by standardized protocols for clinical evaluation, echocardiography, and ECG. In one subset undergoing elective coronary bypass surgery (n = 100) and classified according to LV function, myocardial biopsies will be collected during surgery, and cardiac magnetic resonance (CMR) imaging will be performed at baseline and after 1 year. Blood and tissue samples will be stored in a biobank. We will characterize and compare new-onset HFpEF and HFrEF patients regarding clinical findings and cardiac imaging, genomics, proteomics, and transcriptomics from blood and cardiac biopsies, and by established biomarkers of fibrosis, inflammation, haemodynamics, haemostasis, and thrombosis. The data will be explored by state-of-the-art bioinformatics methods to investigate gene expression patterns, sequence variation, DNA methylation, and post-translational modifications, and using systems biology approaches including pathway and network analysis. CONCLUSIONS: In this epidemiological HF study with biopsy studies in a subset of patients, we aim to identify new biomarkers of disease progression and to find pathophysiological mechanisms to support explorations of new treatment regimens for HFpEF.


Assuntos
Insuficiência Cardíaca , Volume Sistólico , Biomarcadores/sangue , Biópsia , Estudos Epidemiológicos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Suécia/epidemiologia
9.
Curr Genet ; 59(4): 197-206, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24114446

RESUMO

In the yeast Saccharomyces cerevisiae several nutrient transporters have been identified that possess an additional function as nutrient receptor. These transporters are induced when yeast cells are starved for their substrate, which triggers entry into stationary phase and acquirement of a low protein kinase A (PKA) phenotype. Re-addition of the lacking nutrient triggers exit from stationary phase and sudden activation of the PKA pathway, the latter being mediated by the nutrient transceptors. At the same time, the transceptors are ubiquitinated, endocytosed and sorted to the vacuole for breakdown. Investigation of the signaling function of the transceptors has provided a new read-out and new tools for gaining insight into the functionality of transporters. Identification of amino acid residues that bind co-transported ions in symporters has been challenging because the inactivation of transport by site-directed mutagenesis is not conclusive with respect to the cause of the inactivation. The discovery of nontransported agonists of the signaling function in transceptors has shown that transport is not required for signaling. Inactivation of transport with maintenance of signaling in transceptors supports that a true proton-binding residue was mutagenised. Determining the relationship between transport and induction of endocytosis has also been challenging, since inactivation of transport by mutagenesis easily causes loss of all affinity for the substrate. The use of analogues with different combinations of transport and signaling capacities has revealed that transport, ubiquitination and endocytosis can be uncoupled in several unexpected ways. The results obtained are consistent with transporters undergoing multiple substrate-induced conformational changes, which allow interaction with different accessory proteins to trigger specific downstream events.


Assuntos
Proteínas de Membrana Transportadoras/metabolismo , Modelos Moleculares , Conformação Proteica , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/fisiologia , Sequência de Aminoácidos , Sistemas de Transporte de Aminoácidos/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Endocitose/fisiologia , Proteínas de Membrana Transportadoras/química , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosfatos/química , Fosfatos/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Sódio/metabolismo , Ubiquitinação
10.
PLoS One ; 8(6): e65953, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23840382

RESUMO

To assess presence of virus DNA in skin lesions, swab samples from 82 squamous cell carcinomas of the skin (SCCs), 60 actinic keratoses (AKs), paraffin-embedded biopsies from 28 SCCs and 72 kerathoacanthomas (KAs) and fresh-frozen biopsies from 92 KAs, 85 SCCs and 92 AKs were analyzed by high throughput sequencing (HTS) using 454 or Ion Torrent technology. We found total of 4,284 viral reads, out of which 4,168 were Human Papillomavirus (HPV)-related, belonging to 15 known (HPV8, HPV12, HPV20, HPV36, HPV38, HPV45, HPV57, HPV59, HPV104, HPV105, HPV107, HPV109, HPV124, HPV138, HPV147), four previously described putative (HPV 915 F 06 007 FD1, FA73, FA101, SE42) and two putatively new HPV types (SE46, SE47). SE42 was cloned, sequenced, designated as HPV155 and found to have 76% similarity to the most closely related known HPV type. In conclusion, an unbiased approach for viral DNA detection in skin tumors has found that, although some new putative HPVs were found, known HPV types constituted most of the viral DNA.


Assuntos
Alphapapillomavirus/genética , Carcinoma de Células Escamosas/virologia , Ceratoacantoma/virologia , Ceratose Actínica/virologia , Neoplasias Cutâneas/virologia , Alphapapillomavirus/isolamento & purificação , DNA Viral/genética , DNA Viral/isolamento & purificação , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Tipagem Molecular , Sensibilidade e Especificidade , Análise de Sequência de DNA
11.
Biochem Biophys Res Commun ; 436(3): 551-6, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-23770362

RESUMO

In Saccharomyces cerevisiae, Pho89 mediates a cation-dependent transport of Pi across the plasma membrane. This integral membrane protein belongs to the Inorganic Phosphate Transporter (PiT) family, a group that includes the mammalian Na(+)/Pi cotransporters Pit1 and Pit2. Here we report that the Pichia pastoris expressed recombinant Pho89 was purified in the presence of Foscholine-12 and functionally reconstituted into proteoliposomes with a similar substrate specificity as observed in an intact cell system. The alpha-helical content of the Pho89 protein was estimated to 44%. EPR analysis showed that purified Pho89 protein undergoes conformational change upon addition of substrate.


Assuntos
Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/química , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/química , Transporte Biológico , Membrana Celular/química , Dicroísmo Circular , Espectroscopia de Ressonância de Spin Eletrônica , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Pichia/química , Ligação Proteica , Estrutura Secundária de Proteína , Proteolipídeos/química , Proteínas Recombinantes/química , Relação Estrutura-Atividade , Especificidade por Substrato
12.
FEBS J ; 280(3): 965-75, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23216645

RESUMO

The Saccharomyces cerevisiae high-affinity phosphate transporter Pho89 is a member of the inorganic phosphate (Pi) transporter (PiT) family, and shares significant homology with the type III Na(+)/Pi symporters, hPit1 and hPit2. Currently, detailed biochemical and biophysical analyses of Pho89 to better understand its transport mechanisms are limited, owing to the lack of purified Pho89 in an active form. In the present study, we expressed functional Pho89 in the cell membrane of Pichia pastoris, solubilized it in Triton X-100 and foscholine-12, and purified it by immobilized nickel affinity chromatography combined with size exclusion chromatography. The protein eluted as an oligomer on the gel filtration column, and SDS/PAGE followed by western blotting analysis revealed that the protein appeared as bands of approximately 63, 140 and 520 kDa, corresponding to the monomeric, dimeric and oligomeric masses of the protein, respectively. Proteoliposomes containing purified and reconstituted Pho89 showed Na(+)-dependent Pi transport activity driven by an artificially imposed electrochemical Na(+) gradient. This implies that Pho89 operates as a symporter. Moreover, its activity is sensitive to the Na(+) ionophore monensin. To our knowledge, this study represents the first report on the functional reconstitution of a Pi-coupled PiT family member.


Assuntos
Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Transporte Biológico/efeitos dos fármacos , Western Blotting , Membrana Celular/metabolismo , Cromatografia de Afinidade , Cromatografia em Gel , Técnicas Eletroquímicas , Eletroforese em Gel de Poliacrilamida , Peso Molecular , Monensin/farmacologia , Octoxinol/química , Fosfatos/metabolismo , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Pichia/genética , Multimerização Proteica , Proteolipídeos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Ionóforos de Sódio/farmacologia , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/química , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Solubilidade
13.
Virology ; 432(2): 427-34, 2012 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-22819835

RESUMO

Infections during pregnancy have been suggested to be involved in childhood leukemias. We used high-throughput sequencing to describe the viruses most readily detectable in serum samples of pregnant women. Serum DNA of 112 mothers to leukemic children was amplified using whole genome amplification. Sequencing identified one TT virus (TTV) isolate belonging to a known type and two putatively new TTVs. For 22 mothers, we also performed TTV amplification by general primer PCR before sequencing. This detected 39 TTVs, two of which were identical to the TTVs found after whole genome amplification. Altogether, we found 40 TTV isolates, 29 of which were putatively new types (similarities ranging from 89% to 69%). In conclusion, high throughput sequencing is useful to describe the known or unknown viruses that are present in serum samples of pregnant women.


Assuntos
Filogenia , Complicações Infecciosas na Gravidez/virologia , Torque teno virus/genética , Viremia/virologia , Sequência de Aminoácidos , Criança , Pré-Escolar , Infecções por Vírus de DNA/epidemiologia , Infecções por Vírus de DNA/transmissão , Infecções por Vírus de DNA/virologia , DNA Viral/sangue , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Transmissão Vertical de Doenças Infecciosas , Leucemia/epidemiologia , Leucemia/virologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Análise de Sequência de DNA , Torque teno virus/classificação , Torque teno virus/isolamento & purificação , Viremia/epidemiologia , Viremia/transmissão
14.
BMC Biochem ; 13: 11, 2012 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-22726655

RESUMO

BACKGROUND: The Gtr1 protein of Saccharomyces cerevisiae is a member of the RagA subfamily of the Ras-like small GTPase superfamily. Gtr1 has been implicated in various cellular processes. Particularly, the Switch regions in the GTPase domain of Gtr1 are essential for TORC1 activation and amino acid signaling. Therefore, knowledge about the biochemical activity of Gtr1 is required to understand its mode of action and regulation. RESULTS: By employing tryptophan fluorescence analysis and radioactive GTPase assays, we demonstrate that Gtr1 can adopt two distinct GDP- and GTP-bound conformations, and that it hydrolyses GTP much slower than Ras proteins. Using cysteine mutagenesis of Arginine-37 and Valine-67, residues at the Switch I and II regions, respectively, we show altered GTPase activity and associated conformational changes as compared to the wild type protein and the cysteine-less mutant. CONCLUSIONS: The extremely low intrinsic GTPase activity of Gtr1 implies requirement for interaction with activating proteins to support its physiological function. These findings as well as the altered properties obtained by mutagenesis in the Switch regions provide insights into the function of Gtr1 and its homologues in yeast and mammals.


Assuntos
Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , GTP Fosfo-Hidrolases/química , GTP Fosfo-Hidrolases/metabolismo , Guanosina Trifosfato/metabolismo , Dados de Sequência Molecular , Proteínas Monoméricas de Ligação ao GTP/química , Proteínas Monoméricas de Ligação ao GTP/genética , Mutagênese Sítio-Dirigida , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Espectrofotometria Ultravioleta
15.
Biochem J ; 445(3): 413-22, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22587366

RESUMO

In Saccharomyces cerevisiae, the Pho84 phosphate transporter acts as the main provider of phosphate to the cell using a proton symport mechanism, but also mediates rapid activation of the PKA (protein kinase A) pathway. These two features led to recognition of Pho84 as a transceptor. Although the physiological role of Pho84 has been studied in depth, the mechanisms underlying the transport and sensor functions are unclear. To obtain more insight into the structure-function relationships of Pho84, we have rationally designed and analysed site-directed mutants. Using a three-dimensional model of Pho84 created on the basis of the GlpT permease, complemented with multiple sequence alignments, we selected Arg(168) and Lys(492), and Asp(178), Asp(358) and Glu(473) as residues potentially involved in phosphate or proton binding respectively, during transport. We found that Asp(358) (helix 7) and Lys(492) (helix 11) are critical for the transport function, and might be part of the putative substrate-binding pocket of Pho84. Moreover, we show that alleles mutated in the putative proton-binding site Asp(358) are still capable of strongly activating PKA pathway targets, despite their severely reduced transport activity. This indicates that signalling does not require transport and suggests that mutagenesis of amino acid residues involved in binding of the co-transported ion may constitute a promising general approach to separate the transport and signalling functions in transceptors.


Assuntos
Simportadores de Próton-Fosfato/genética , Simportadores de Próton-Fosfato/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , DNA Fúngico/genética , Genes Fúngicos , Cinética , Modelos Biológicos , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosfatos/metabolismo , Simportadores de Próton-Fosfato/química , Prótons , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Homologia de Sequência de Aminoácidos , Transdução de Sinais
16.
BMC Microbiol ; 11: 2, 2011 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-21194495

RESUMO

BACKGROUND: Chronic fatigue syndrome is an idiopathic syndrome widely suspected of having an infectious or immune etiology. We applied an unbiased metagenomic approach to try to identify known or novel infectious agents in the serum of 45 cases with chronic fatigue syndrome or idiopathic chronic fatigue. Controls were the unaffected monozygotic co-twins of cases, and serum samples were obtained at the same place and time. RESULTS: No novel DNA or RNA viral signatures were confidently identified. Four affected twins and no unaffected twins evidenced viremia with GB virus C (8.9% vs. 0%, p = 0.019), and one affected twin had previously undetected hepatitis C viremia. An excess of GB virus C viremia in cases with chronic fatigue requires confirmation. CONCLUSIONS: Current, impairing chronic fatigue was not robustly associated with viremia detectable in serum.


Assuntos
Síndrome de Fadiga Crônica/genética , Vírus GB C/genética , Metagenômica/métodos , Gêmeos Monozigóticos/genética , Viremia/genética , Adulto , Doenças Transmissíveis , Estudos Transversais , DNA Viral/sangue , Doenças em Gêmeos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Fatores de Risco
17.
Biopsychosoc Med ; 4(1): 5, 2010 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-20525319

RESUMO

BACKGROUND: Alexithymia is a disturbance associated with psychosomatic disorders, pain syndromes, and a variety of psychiatric disorders. The Affect School (AS) based on Tomkins Affect Theory is a therapy focusing on innate affects and their physiological expressions, feelings, emotions and scripts. In this pilot study we tried the AS-intervention method in patients with chronic benign pain. METHODS: The AS-intervention, with 8 weekly group sessions and 10 individual sessions, was offered to 59 patients with chronic non-malignant pain at a pain rehabilitation clinic in Sweden 2004-2005. Pre and post intervention assessments were done with the Hospital Anxiety and Depression scale (HAD), the Toronto Alexithymia Scale-20 (TAS-20), the Visual Analogue Scale for pain assessment (VAS-pain), the European Quality of Life health barometer (EQoL) and the Stress and Crisis Inventory-93 (SCI-93). After the group sessions we used Bergdahl's Questionnaire for assessing changes in interpersonal relations, general well-being and evaluation of AS. RESULTS: The AS intervention was completed by 54 out of 59 (92%) patients. Significant reductions in total TAS-20 post-test scores (p = 0.0006) as well as TAS-20 DIF and DDF factors (Difficulties Identifying Feelings, and Difficulties Describing Feelings) were seen (p = 0.0001, and p = 0.0008) while the EOT factor (Externally Oriented Thinking) did not change. Improvements of HAD-depression scores (p = 0.04), EQoL (p = 0.02) and self-assessed changes in relations to others (p < 0.001) were also seen. After Bonferroni Correction for Multiple Analyses the TAS-20 test score reduction was still significant as well as Bergdahl's test after group sessions. The HAD, EQoL, SCI-93, and VAS-pain scores were not significantly changed. The AS-intervention was ranked high by the participants. CONCLUSIONS: This pilot study involving 59 patients with chronic benign pain indicates that the alexithymia DIF and DDF, as well as depression, social relations and quality of life may be improved by the Affect School therapeutic intervention.

18.
BMC Res Notes ; 2: 180, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19747390

RESUMO

BACKGROUND: The BRICHOS domain has been found in 8 protein families with a wide range of functions and a variety of disease associations, such as respiratory distress syndrome, dementia and cancer. The domain itself is thought to have a chaperone function, and indeed three of the families are associated with amyloid formation, but its structure and many of its functional properties are still unknown. FINDINGS: The proteins in the BRICHOS superfamily have four regions with distinct properties. We have analysed the BRICHOS proteins focusing on sequence conservation, amino acid residue properties, native disorder and secondary structure predictions. Residue conservation shows large variations between the regions, and the spread of residue conservation between different families can vary greatly within the regions. The secondary structure predictions for the BRICHOS proteins show remarkable coherence even where sequence conservation is low, and there seems to be little native disorder. CONCLUSIONS: The greatly variant rates of conservation indicates different functional constraints among the regions and among the families. We present three previously unknown BRICHOS families; group A, which may be ancestral to the ITM2 families; group B, which is a close relative to the gastrokine families, and group C, which appears to be a truly novel, disjoint BRICHOS family. The C-terminal region of group C has nearly identical sequences in all species ranging from fish to man and is seemingly unique to this family, indicating critical functional or structural properties.

19.
Clin Immunol ; 133(3): 353-63, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19786367

RESUMO

The etiology of sarcoidosis remains unknown. Recently, by mass spectrometric sequencing of peptides eluted from HLA-DR molecules of bronchoalveolar lavage (BAL) cells from DRB10301(pos) patients, we identified potential self-antigens in sarcoidosis. The aim of the present study was to investigate the capacity of selected peptides to stimulate lung and blood T cells of sarcoidosis patients using an interferon-gamma ELISPOT assay. In peripheral blood, there were strong T cell responses to a peptide derived from the cytoskeletal protein vimentin in 6 out of 11 DRB10301(pos) patients with active disease but not in patients with other HLA types. BAL T cell responses against peptides derived from ATP synthase or from lysyl-tRNA synthetase were detected in DRB10301(pos) as well as DRB10301(neg) patients. By using antigenic peptides presented in vivo in the lungs of sarcoidosis patients, we have identified blood and lung T cell autoimmune responses that may help sustain the inflammation in this disease.


Assuntos
Autoanticorpos/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Linfócitos T CD4-Positivos/imunologia , Antígenos HLA-DR/imunologia , Fragmentos de Peptídeos/imunologia , Sarcoidose Pulmonar/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Aminoacil-tRNA Sintetases/imunologia , Autoanticorpos/sangue , Líquido da Lavagem Broncoalveolar/citologia , Broncoscopia , DNA/química , DNA/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sarcoidose Pulmonar/sangue , Estatísticas não Paramétricas , Vimentina/imunologia
20.
FEBS J ; 276(15): 4142-55, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19558493

RESUMO

A method has been developed to predict the effects of mutations in the p53 cancer suppressor gene. The new method uses novel parameters combined with previously established parameters. The most important parameter is the stability measure of the mutated structure calculated using molecular modelling. For each mutant, a severity score is reported, which can be used for classification into deleterious and nondeleterious. Both structural features and sequence properties are taken into account. The method has a prediction accuracy of 77% on all mutants and 88% on breast cancer mutations affecting WAF1 promoter binding. When compared with earlier methods, using the same dataset, our method clearly performs better. As a result of the severity score calculated for every mutant, valuable knowledge can be gained regarding p53, a protein that is believed to be involved in over 50% of all human cancers.


Assuntos
Neoplasias da Mama/genética , Mutação , Proteína Supressora de Tumor p53/genética , Algoritmos , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Humanos , Modelos Moleculares , Neoplasias/genética , Neoplasias/prevenção & controle , Regiões Promotoras Genéticas , Ligação Proteica , Conformação Proteica , Índice de Gravidade de Doença , Proteína Supressora de Tumor p53/química
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