Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38682236

RESUMO

Sickle cell disease (SCD) associated chronic hemolysis promotes oxidative stress, inflammation and thrombosis leading to organ damage, including liver damage. Hemoglobin scavenger receptor CD163 plays a protective role in SCD by scavenging both hemoglobin-haptoglobin complexes and cell free hemoglobin. A limited number of studies in the past have shown a positive correlation of CD163 expression with poor disease outcomes in patients with SCD. However, the role and regulation of CD163 in SCD related hepatobiliary injury has not been fully elucidated yet. Here, we show that chronic liver injury in SCD patients is associated with elevated levels of hepatic membrane bound CD163. Hemolysis and increase in hepatic heme, hemoglobin and iron levels elevate CD163 expression in the SCD mouse liver. Mechanistically we show that HO-1 positively regulates membrane bound CD163 expression independent of NRF2 signaling in SCD liver. We further demonstrate that of the interaction between CD163 and HO-1 is not dependent on CD163-hemoglobin binding. These findings indicate that CD163 is a potential biomarker of SCD associated hepatobiliary injury. Understanding the role of HO-1 in membrane bound CD163 regulation may help identify novel therapeutic targets for hemolysis induced chronic liver injury.

2.
Blood ; 140(9): 1020-1037, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35737916

RESUMO

Acute lung injury, referred to as the acute chest syndrome, is a major cause of morbidity and mortality in patients with sickle cell disease (SCD), which often occurs in the setting of a vaso-occlusive painful crisis. P-selectin antibody therapy reduces hospitalization of patients with SCD by ∼50%, suggesting that an unknown P-selectin-independent mechanism promotes remaining vaso-occlusive events. In patients with SCD, intraerythrocytic polymerization of mutant hemoglobin promotes ischemia-reperfusion injury and hemolysis, which leads to the development of sterile inflammation. Using intravital microscopy in transgenic, humanized mice with SCD and in vitro studies with blood from patients with SCD, we reveal for the first time that the sterile inflammatory milieu in SCD promotes caspase-4/11-dependent activation of neutrophil-gasdermin D (GSDMD), which triggers P-selectin-independent shedding of neutrophil extracellular traps (NETs) in the liver. Remarkably, these NETs travel intravascularly from liver to lung, where they promote neutrophil-platelet aggregation and the development of acute lung injury. This study introduces a novel paradigm that liver-to-lung embolic translocation of NETs promotes pulmonary vascular vaso-occlusion and identifies a new GSDMD-mediated, P-selectin-independent mechanism of lung injury in SCD.


Assuntos
Lesão Pulmonar Aguda , Anemia Falciforme , Armadilhas Extracelulares , Proteínas de Ligação a Fosfato , Proteínas Citotóxicas Formadoras de Poros , Traumatismo por Reperfusão , Lesão Pulmonar Aguda/etiologia , Animais , Fígado , Pulmão/irrigação sanguínea , Camundongos , Camundongos Transgênicos , Selectina-P , Proteínas de Ligação a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Traumatismo por Reperfusão/complicações
3.
Angew Chem Int Ed Engl ; 63(8): e202310862, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38072831

RESUMO

Quantitative and selective labelling of proteins is widely used in both academic and industrial laboratories, and catalytic labelling of proteins using transpeptidases, such as sortases, has proved to be a popular strategy for such selective modification. A major challenge for this class of enzymes is that the majority of procedures require an excess of the labelling reagent or, alternatively, activated substrates rather than simple commercially sourced peptides. We report the use of a coupled enzyme strategy which enables quantitative N- and C-terminal labelling of proteins using unactivated labelling peptides. The use of an aminopeptidase in conjunction with a transpeptidase allows sequence-specific degradation of the peptide by-product, shifting the equilibrium to favor product formation, which greatly enhances the reaction efficiency. Subsequent optimisation of the reaction allows N-terminal labelling of proteins using essentially equimolar ratios of peptide label to protein and C-terminal labelling with only a small excess. Minimizing the amount of substrate required for quantitative labelling has the potential to improve industrial processes and facilitate the use of transpeptidation as a method for protein labelling.


Assuntos
Aminoaciltransferases , Peptidil Transferases , Aminopeptidases , Proteínas de Bactérias/metabolismo , Aminoaciltransferases/metabolismo , Peptídeos/metabolismo
4.
J Am Chem Soc ; 145(2): 1083-1096, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36583539

RESUMO

Finding new mechanistic solutions for biocatalytic challenges is key in the evolutionary adaptation of enzymes, as well as in devising new catalysts. The recent release of man-made substances into the environment provides a dynamic testing ground for observing biocatalytic innovation at play. Phosphate triesters, used as pesticides, have only recently been introduced into the environment, where they have no natural counterpart. Enzymes have rapidly evolved to hydrolyze phosphate triesters in response to this challenge, converging onto the same mechanistic solution, which requires bivalent cations as a cofactor for catalysis. In contrast, the previously identified metagenomic promiscuous hydrolase P91, a homologue of acetylcholinesterase, achieves slow phosphotriester hydrolysis mediated by a metal-independent Cys-His-Asp triad. Here, we probe the evolvability of this new catalytic motif by subjecting P91 to directed evolution. By combining a focused library approach with the ultrahigh throughput of droplet microfluidics, we increase P91's activity by a factor of ≈360 (to a kcat/KM of ≈7 × 105 M-1 s-1) in only two rounds of evolution, rivaling the catalytic efficiencies of naturally evolved, metal-dependent phosphotriesterases. Unlike its homologue acetylcholinesterase, P91 does not suffer suicide inhibition; instead, fast dephosphorylation rates make the formation of the covalent adduct rather than its hydrolysis rate-limiting. This step is improved by directed evolution, with intermediate formation accelerated by 2 orders of magnitude. Combining focused, combinatorial libraries with the ultrahigh throughput of droplet microfluidics can be leveraged to identify and enhance mechanistic strategies that have not reached high efficiency in nature, resulting in alternative reagents with novel catalytic machineries.


Assuntos
Hidrolases , Hidrolases de Triester Fosfórico , Acetilcolinesterase , Hidrolases de Triester Fosfórico/genética , Hidrolases de Triester Fosfórico/metabolismo , Biocatálise , Catálise
5.
Anal Chem ; 95(10): 4597-4604, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36848587

RESUMO

Droplet microfluidics is a valuable method to "beat the odds" in high throughput screening campaigns such as directed evolution, where valuable hits are infrequent and large library sizes are required. Absorbance-based sorting expands the range of enzyme families that can be subjected to droplet screening by expanding possible assays beyond fluorescence detection. However, absorbance-activated droplet sorting (AADS) is currently ∼10-fold slower than typical fluorescence-activated droplet sorting (FADS), meaning that, in comparison, a larger portion of sequence space is inaccessible due to throughput constraints. Here we improve AADS to reach kHz sorting speeds in an order of magnitude increase over previous designs, with close-to-ideal sorting accuracy. This is achieved by a combination of (i) the use of refractive index matching oil that improves signal quality by removal of side scattering (increasing the sensitivity of absorbance measurements); (ii) a sorting algorithm capable of sorting at this increased frequency with an Arduino Due; and (iii) a chip design that transmits product detection better into sorting decisions without false positives, namely a single-layered inlet to space droplets further apart and injections of "bias oil" providing a fluidic barrier preventing droplets from entering the incorrect sorting channel. The updated ultra-high-throughput absorbance-activated droplet sorter increases the effective sensitivity of absorbance measurements through better signal quality at a speed that matches the more established fluorescence-activated sorting devices.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Microfluídica/métodos , Ensaios de Triagem em Larga Escala
6.
Blood ; 137(19): 2676-2680, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33619560

RESUMO

Sickle cell disease (SCD) is caused by a homozygous mutation in the ß-globin gene, which leads to erythrocyte sickling, vasoocclusion, and intense hemolysis. P-selectin inhibition has been shown to prevent vasoocclusive events in patients with SCD; however, the chronic effect of P-selectin inhibition in SCD remains to be determined. Here, we used quantitative liver intravital microscopy in our recently generated P-selectin-deficient SCD mice to show that chronic P-selectin deficiency attenuates liver ischemia but fails to prevent hepatobiliary injury. Remarkably, we find that this failure in resolution of hepatobiliary injury in P-selectin-deficient SCD mice is associated with the increase in cellular senescence and reduced epithelial cell proliferation in the liver. These findings highlight the importance of investigating the long-term effects of chronic P-selectin inhibition therapy on liver pathophysiology in patients with SCD.


Assuntos
Anemia Falciforme/patologia , Isquemia/patologia , Fígado/irrigação sanguínea , Selectina-P/deficiência , Anemia Falciforme/fisiopatologia , Animais , Arteriopatias Oclusivas/etiologia , Arteriopatias Oclusivas/patologia , Senescência Celular , Células Epiteliais/patologia , Heme Oxigenase-1/análise , Hemólise , Fígado/patologia , Fígado/fisiopatologia , Proteínas de Membrana/análise , Camundongos , Camundongos Knockout , Modelos Animais , Selectina-P/genética
7.
Haematologica ; 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941440

RESUMO

Sickle cell disease (SCD) is a monogenic disorder that affects 100,000 African Americans and millions of people worldwide. Intra-erythrocytic polymerization of sickle hemoglobin (HbS) promotes erythrocyte sickling, impaired rheology, ischemia and hemolysis, leading to the development of progressive liver injury in SCD. Liver resident macrophages and monocytes are known to enable the clearance of HbS, however, the role of liver sinusoidal endothelial cells (LSECs) in HbS clearance and liver injury in SCD remains unknown. Using real-time intravital (in vivo) imaging in the mice liver as well as flow cytometric analysis and confocal imaging of primary human LSECs, we show for the first time that liver injury in SCD is associated with accumulation of HbS and iron in the LSECs, leading to LSEC senescence. Hb uptake by LSECs was mediated by micropinocytosis. Hepatic monocytes were observed to attenuate LSECsenescence by accelerating HbS clearance in the liver of SCD mice, however, this protection was impaired in P-selectin-deficient SCD mice secondary to reduced monocyte recruitment in the liver. These findings are the first to suggest that LSECs contribute to HbS clearance and HbS induced LSEC-senescence promotes progressive liver injury in SCD mice. Our results provide a novel insight into the pathogenesis of hemolysis induced chronic liver injury in SCD caused by LSEC senescence. Identifying the regulators of LSEC mediated HbS clearance may lead to new therapies to prevent the progression of liver injury in SCD.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38140772

RESUMO

BACKGROUND: Psoriasis is one of the most common dermatoses associated with a variety of comorbidities. There have been some reports on its possible association with ocular disorders however dry eye syndrome (DES) in such patients has been poorly investigated. OBJECTIVES: To investigate the frequency of DES symptoms in psoriatic patients, also regarding psoriasis severity in PASI, manifestation and therapy. METHODS: 40 patients with psoriasis and 40 volunteers without dermatoses were enrolled in the study. They completed Ocular Surface Disease Index (OSDI) questionnaire and were objectively examined by IDRA® device to perform automatic interferometry, automatic meibography of lower eyelid glands, non-invasive break-up time (NIBUT), blink quality and tear meniscus height. RESULTS: Patients with psoriasis had statistically significantly thicker lipid layer (p = 0.0042 left eye, p = 0.0313 right eye) and greater loss of Meibomian glands compared to controls (p = 0.0128 left eye, p = 0.048 right eye). The patients had lower, although insignificantly, eye blink quality and tear meniscus height than the control group, as well as shorter NIBUT and higher score in OSDI. After the division of patients into two groups-with or without nails involvement/psoriatic arthritis/systemic treatment- we did not observe any significant differences between the groups. PASI did not correlate with any DES parameter. CONCLUSIONS: This is the first study of DES symptoms with an objective IDRA® analyzer. We managed to observe that patients with psoriasis have thicker lipid layer and higher Meibomian glands' loss in lower eyelids. Based on all assessed objective and subjective parameters psoriatics do not seem to have an increased risk of DES. The presence of psoriatic arthritis or nail involvement does not seem to be a predisposing factor for DES development. PASI probably cannot be a prognostic factor for any of the DES-associated parameters. Nevertheless, DES in psoriasis requires further research on bigger samples to establish reliable recommendations.

9.
Am J Physiol Cell Physiol ; 322(3): C508-C520, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34986022

RESUMO

Aging is the most significant risk factor for the majority of chronic diseases, including liver disease. The cellular, molecular, and pathophysiological mechanisms that promote age-induced hepatovascular changes are unknown due to our inability to visualize changes in liver pathophysiology in live mice over time. We performed quantitative liver intravital microscopy (qLIM) in live C57BL/6J mice to investigate the impact of aging on the hepatovascular system over a 24-mo period. qLIM revealed that age-related hepatic alterations include reduced liver sinusoidal blood flow, increased sinusoidal vessel diameter, and loss of small hepatic vessels. The ductular cell structure deteriorates with age, along with altered expression of hepatic junctional proteins. Furthermore, qLIM imaging revealed increased inflammation in the aged liver, which was linked to increased expression of proinflammatory macrophages, hepatic neutrophils, liver sinusoidal endothelial cells, senescent cells, and procoagulants. Finally, we detected elevated NF-κB pathway activity in aged livers. Overall, these findings emphasize the importance of inflammation in age-related hepatic vasculo-epithelial alterations and highlight the utility of qLIM in studying age-related effects in organ pathophysiology.


Assuntos
Células Endoteliais , Fígado , Animais , Inflamação/metabolismo , Microscopia Intravital , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
10.
Bioconjug Chem ; 33(12): 2341-2347, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36356167

RESUMO

Staphylococcus aureus sortase A is a transpeptidase that has been extensively exploited for site-specific modification of proteins and was originally used to attach a labeling reagent containing an LPXTG recognition sequence to a protein or peptide with an N-terminal glycine. Sortase mutants with other recognition sequences have also been reported, but in all cases, the reversibility of the transpeptidation reaction limits the efficiency of sortase-mediated labeling reactions. For the wildtype sortase, depsipeptide substrates, in which the scissile peptide bond is replaced with an ester, allow effectively irreversible sortase-mediated labeling as the alcohol byproduct is a poor competing nucleophile. In this paper, the use of depsipeptide substrates for evolved sortase variants is reported. Substrate specificities of three sortases have been investigated allowing identification of an orthogonal pair of enzymes accepting LPEToG and LPESoG depsipeptides, which have been applied to dual N-terminal labeling of a model protein mutant containing a second, latent N-terminal glycine residue. The method provides an efficient orthogonal site-specific labeling technique that further expands the biochemical protein labeling toolkit.


Assuntos
Aminoaciltransferases , Depsipeptídeos , Staphylococcus aureus , Aminoaciltransferases/química , Proteínas de Bactérias/química , Glicina , Indicadores e Reagentes
11.
Medicina (Kaunas) ; 58(4)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35454311

RESUMO

Diabetes Mellitus (DM) is amongst the most notable causes of years of life lost worldwide and its prevalence increases perpetually. The disease is characterized as multisystemic dysfunctions attributed to hyperglycemia resulting directly from insulin resistance (IR), inadequate insulin secretion, or enormous glucagon secretion. Insulin is a highly anabolic peptide hormone that regulates blood glucose levels by hastening cellular glucose uptake as well as controlling carbohydrate, protein, and lipid metabolism. In the course of Type 2 Diabetes Mellitus (T2DM), which accounts for nearly 90% of all cases of diabetes, the insulin response is inadequate, and this condition is defined as Insulin Resistance. IR sequela include, but are not limited to, hyperglycemia, cardiovascular system impairment, chronic inflammation, disbalance in oxidative stress status, and metabolic syndrome occurrence. Despite the substantial progress in understanding the molecular and metabolic pathways accounting for injurious effects of IR towards multiple body organs, IR still is recognized as a ferocious enigma. The number of widely available therapeutic approaches is growing, however, the demand for precise, safe, and effective therapy is also increasing. A literature search was carried out using the MEDLINE/PubMed, Google Scholar, SCOPUS and Clinical Trials Registry databases with a combination of keywords and MeSH terms, and papers published from February 2021 to March 2022 were selected as recently published papers. This review paper aims to provide critical, concise, but comprehensive insights into the advances in the treatment of IR that were achieved in the last months.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Humanos , Hiperglicemia/tratamento farmacológico , Insulina/metabolismo , Redes e Vias Metabólicas
12.
Postepy Dermatol Alergol ; 39(2): 307-315, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35645688

RESUMO

Introduction: Omentin and vaspin are considered to have beneficial effects preventing the development of metabolic disorders which are common comorbidities in psoriasis. Aim: To evaluate the serum level of these adipokines in psoriatic patients and elucidate possible associations with disease activity, metabolic or inflammatory parameters and systemic treatment. Material and methods: Thirty-three patients with active plaque-type psoriasis and 11 healthy controls participated in the study. Blood samples were collected before and after 3 months of treatment with acitretin or methotrexate. Results: Serum vaspin concentration in psoriatic patients was significantly lower than in the control group (p < 0.05). No correlation between adipokines and severity of disease evaluated with PASI was found. However, median vaspin levels decreased with the severity of skin lesions and the omentin level was higher in patients with severe disease versus those with moderate form (p < 0.05). The vaspin level correlated with BMI of psoriatic patients (p < 0.05), with cholesterol and triglycerides levels (p = 0.054, p = 0.049, respectively). No significant effect of systemic treatment on omentin levels was found. Regarding vaspin, we observed an upward trend in its concentration after treatment. Conclusions: Omentin and vaspin may play a modulating role in the systemic inflammation present in psoriasis and thus may contribute to the development of metabolic complications.

13.
Chembiochem ; 22(23): 3292-3299, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34643305

RESUMO

The exploration of large DNA libraries of metagenomic or synthetic origin is greatly facilitated by ultrahigh-throughput assays that use monodisperse water-in-oil emulsion droplets as sequestered reaction compartments. Millions of samples can be generated and analysed in microfluidic devices at kHz speeds, requiring only micrograms of reagents. The scope of this powerful platform for the discovery of new sequence space is, however, hampered by the limited availability of assay substrates, restricting the functions and reaction types that can be investigated. Here, we broaden the scope of detectable biochemical transformations in droplet microfluidics by introducing the first fluorogenic assay for alcohol dehydrogenases (ADHs) in this format. We have synthesized substrates that release a pyranine fluorophore (8-hydroxy-1,3,6-pyrenetrisulfonic acid, HPTS) when enzymatic turnover occurs. Pyranine is well retained in droplets for >6 weeks (i. e. 14-times longer than fluorescein), avoiding product leakage and ensuring excellent assay sensitivity. Product concentrations as low as 100 nM were successfully detected, corresponding to less than one turnover per enzyme molecule on average. The potential of our substrate design was demonstrated by efficient recovery of a bona fide ADH with an >800-fold enrichment. The repertoire of droplet screening is enlarged by this sensitive and direct fluorogenic assay to identify dehydrogenases for biocatalytic applications.


Assuntos
Álcool Desidrogenase/análise , Corantes Fluorescentes/química , Ensaios de Triagem em Larga Escala , Dispositivos Lab-On-A-Chip , Álcool Desidrogenase/metabolismo , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Estrutura Molecular , Tamanho da Partícula
14.
Respir Res ; 22(1): 100, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823868

RESUMO

BACKGROUND: Whole lung tissue transcriptomic profiling studies in chronic obstructive pulmonary disease (COPD) have led to the identification of several genes associated with the severity of airflow limitation and/or the presence of emphysema, however, the cell types driving these gene expression signatures remain unidentified. METHODS: To determine cell specific transcriptomic changes in severe COPD, we conducted single-cell RNA sequencing (scRNA seq) on n = 29,961 cells from the peripheral lung parenchymal tissue of nonsmoking subjects without underlying lung disease (n = 3) and patients with severe COPD (n = 3). The cell type composition and cell specific gene expression signature was assessed. Gene set enrichment analysis (GSEA) was used to identify the specific cell types contributing to the previously reported transcriptomic signatures. RESULTS: T-distributed stochastic neighbor embedding and clustering of scRNA seq data revealed a total of 17 distinct populations. Among them, the populations with more differentially expressed genes in cases vs. controls (log fold change >|0.4| and FDR = 0.05) were: monocytes (n = 1499); macrophages (n = 868) and ciliated epithelial cells (n = 590), respectively. Using GSEA, we found that only ciliated and cytotoxic T cells manifested a trend towards enrichment of the previously reported 127 regional emphysema gene signatures (normalized enrichment score [NES] = 1.28 and = 1.33, FDR = 0.085 and = 0.092 respectively). Among the significantly altered genes present in ciliated epithelial cells of the COPD lungs, QKI and IGFBP5 protein levels were also found to be altered in the COPD lungs. CONCLUSIONS: scRNA seq is useful for identifying transcriptional changes and possibly individual protein levels that may contribute to the development of emphysema in a cell-type specific manner.


Assuntos
Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/genética , Proteínas de Ligação a RNA/genética , RNA/genética , Análise de Sequência de RNA/métodos , Transcriptoma/genética , Adulto , Idoso , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , RNA/metabolismo , Proteínas de Ligação a RNA/biossíntese , Índice de Gravidade de Doença , Adulto Jovem
15.
Nature ; 520(7547): 322-4, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-25799986

RESUMO

CK Vulpeculae was observed in outburst in 1670-1672 (ref. 1), but no counterpart was seen until 1982, when a bipolar nebula was found at its location. Historically, CK Vul has been considered to be a nova (Nova Vul 1670), but its similarity to 'red transients', which are more luminous than classical novae and thought to be the results of stellar collisions, has re-opened the question of CK Vul's status. Red transients cool to resemble late M-type stars, surrounded by circumstellar material rich in molecules and dust. No stellar source has been seen in CK Vul, though a radio continuum source was identified at the expansion centre of the nebula. Here we report that CK Vul is surrounded by chemically rich molecular gas in the form of an outflow, as well as dust. The gas has peculiar isotopic ratios, revealing that CK Vul's composition was strongly enhanced by the nuclear ashes of hydrogen burning. The chemical composition cannot be reconciled with a nova or indeed any other known explosion. In addition, the mass of the surrounding gas is too large for a nova, though the conversion from observations of CO to a total mass is uncertain. We conclude that CK Vul is best explained as the remnant of a merger of two stars.

16.
Postepy Dermatol Alergol ; 38(6): 1023-1031, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35126010

RESUMO

INTRODUCTION: Krüppel-like factor 4 (KLF4) is a transcription factor of anti-inflammatory and anti-thrombotic properties not studied in psoriasis yet. AIM: To analyze the clinical value of the serum KLF4 level in psoriatics and elucidate the interplay between disease activity, metabolic or inflammatory parameters and systemic therapy. MATERIAL AND METHODS: The study enrolled thirty-four psoriatics and fifteen healthy subjects. Blood samples were collected before and after twelve weeks of treatment with methotrexate or acitretin. Serum KLF4 levels were measured using immune-enzymatic method. RESULTS: Serum KLF4 levels in psoriatic patients did not statistically differ comparing to the controls (p > 0.05). However, in severe psoriasis, KLF4 was significantly higher than in healthy ones before treatment and normalized after treatment to baseline levels of controls (p < 0.05, p > 0.05, respectively). KLF4 positively correlated with body mass index (p = 0.038) but not with psoriasis severity, nor inflammatory or metabolic markers. Interestingly, many pro-atherogenic parameters were shown as variables independently predicting the levels of KLF4. No significant effect of three-month systemic treatment on KLF4 was found. CONCLUSIONS: KLF4 may be a novel independent indicator of the proatherogenic risk in psoriatics, especially with a severe form or obesity.

17.
Nature ; 516(7530): 219-21, 2014 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-25409140

RESUMO

The age of dense interstellar cloud cores, where stars and planets form, is a crucial parameter in star formation and difficult to measure. Some models predict rapid collapse, whereas others predict timescales of more than one million years (ref. 3). One possible approach to determining the age is through chemical changes as cloud contraction occurs, in particular through indirect measurements of the ratio of the two spin isomers (ortho/para) of molecular hydrogen, H2, which decreases monotonically with age. This has been done for the dense cloud core L183, for which the deuterium fractionation of diazenylium (N2H(+)) was used as a chemical clock to infer that the core has contracted rapidly (on a timescale of less than 700,000 years). Among astronomically observable molecules, the spin isomers of the deuterated trihydrogen cation, ortho-H2D(+) and para-H2D(+), have the most direct chemical connections to H2 (refs 8, 9, 10, 11, 12) and their abundance ratio provides a chemical clock that is sensitive to greater cloud core ages. So far this ratio has not been determined because para-H2D(+) is very difficult to observe. The detection of its rotational ground-state line has only now become possible thanks to accurate measurements of its transition frequency in the laboratory, and recent progress in instrumentation technology. Here we report observations of ortho- and para-H2D(+) emission and absorption, respectively, from the dense cloud core hosting IRAS 16293-2422 A/B, a group of nascent solar-type stars (with ages of less than 100,000 years). Using the ortho/para ratio in conjunction with chemical models, we find that the dense core has been chemically processed for at least one million years. The apparent discrepancy with the earlier N2H(+) work arises because that chemical clock turns off sooner than the H2D(+) clock, but both results imply that star-forming dense cores have ages of about one million years, rather than 100,000 years.

18.
Sensors (Basel) ; 20(18)2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32899589

RESUMO

Methods used to evaluate the impact of Intelligent Transport System (ITS) services on road safety are usually based on expert assessments or statistical studies. However, commonly used methods are challenging to apply in the planning process of ITS services. This paper presents the methodology of research using surrogate safety measures calculated and calibrated with the use of simulation techniques and a driving simulator. This approach supports the choice of the type of ITS services that are beneficial for traffic efficiency and road safety. This paper presents results of research on the influence of selected scenarios of variable speed limits on the efficiency and safety of traffic on the sections of motorways and expressways in various traffic conditions. The driving simulator was used to estimate the efficiency of lane-keeping by the driver. The simulation traffic models were calibrated using driving simulator data and roadside sensor data. The traffic models made it possible to determine surrogate safety measures (number of conflicts and their severity) in selected scenarios of using ITS services. The presented studies confirmed the positive impact of Variable Speed Limits (VSLs) on the level of road safety and traffic efficiency. This paper also presents recommendations and plans for further research in this area.

19.
Int J Mol Sci ; 21(10)2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32456228

RESUMO

Psoriasis is a systemic, immune-metabolic disease with strong genetic predispositions and autoimmune pathogenic traits. During psoriasis progression, a wide spectrum of comorbidities comes into play with the leading role of the cardio-metabolic syndrome (CMS) that occurs with the frequency of 30-50% amongst the psoriatic patients. Both conditions-psoriasis and CMS-have numerous common pathways, mainly related to proinflammatory pathways and cytokine profiles. Surprisingly, despite the years of research, the exact pathways linking the occurrence of CMS in the psoriasis population are still not fully understood. Recently published papers, both clinical and based on the basic science, shed new light into this relationship providing an insight into novel key-players proteins with plausible effects on above-mentioned interplay. Taking into account recent advances in this important medical matter, this review aims to discuss comprehensively the role of four proteins: proprotein convertase subtilisin/kexin type-9 (PSCK9), angiopoietin-like protein 8 (ANGPLT8), sortilin (SORT1), and cholesteryl ester transfer proteins (CEPT) as plausible links between psoriasis and CMS.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Semelhantes a Angiopoietina/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Síndrome Metabólica/metabolismo , Hormônios Peptídicos/metabolismo , Pró-Proteína Convertase 9/metabolismo , Psoríase/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteína 8 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/genética , Animais , Proteínas de Transferência de Ésteres de Colesterol/genética , Humanos , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Hormônios Peptídicos/genética , Pró-Proteína Convertase 9/genética , Psoríase/complicações
20.
Int J Mol Sci ; 21(13)2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32605214

RESUMO

Selenoprotein P (SeP), a member of hepatokines, is involved in the development of various metabolic diseases closely related to psoriasis, but it has not been explored in that dermatosis so far. The study aimed to evaluate the clinical value of serum SeP concentrations in patients with psoriasis and its interplay between disease activity, metabolic or inflammatory parameters and systemic therapy. The study included thirty-three patients with flared plaque-type psoriasis and fifteen healthy volunteers. Blood samples were collected before and after three months of treatment with methotrexate or acitretin. Serum SeP levels were evaluated using the immune-enzymatic method. SeP concentration was significantly higher in patients with psoriasis than in the controls (p < 0.05). Further, in patients with severe psoriasis, SeP was significantly increased, compared with the healthy volunteers before treatment, and significantly decreased after (p < 0.05, p = 0.041, respectively). SeP positively correlated with C-reactive protein and platelets and negatively with red blood counts (p = 0.008, p = 0.013, p = 0.022, respectively). Therapy resulted in a significant decrease in SeP level. Selenoprotein P may be a novel indicator of inflammation and the metabolic complications development in psoriatics, especially with severe form or with concomitant obesity. Classic systemic therapy has a beneficial effect on reducing the risk of comorbidities by inhibiting SeP.


Assuntos
Biomarcadores/sangue , Síndrome Metabólica/diagnóstico , Psoríase/complicações , Selenoproteína P/sangue , Adulto , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA