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1.
Breast Cancer Res Treat ; 205(3): 475-485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38453782

RESUMO

PURPOSE: The prognostic utility and biological correlates of neutrophil to lymphocyte ratio (NLR), a potential biomarker of the balance between immune response and the inflammatory status, are still uncertain in breast cancer (BC). METHODS: We analysed a cohort of 959 women with early breast cancer, mostly treated with neoadjuvant or adjuvant chemotherapy. Clinical and pathological data, survival, NLR (continuous and categorical) and stromal tumor infiltrating lymphocytes (sTIL) were evaluated. RESULTS: NLR was only weakly associated with Ki67, while no association was found for grade, histology, immunohistochemical subtype or stage. Lymphocyte infiltration of the tumor did not correlate with NLR (Rho: 0.05, p = 0.30). These results were similar in the whole group and across the different BC subtypes, with no differences in triple negative BC. Relapse free interval (RFI), breast cancer specific survival (BCSS) and overall survival (OS) changed according to pre-treatment NLR neither in the univariate nor in the multivariate Cox models (RFI: HR 0.948, p = 0.61; BCSS: HR 0.920, p = 0.57; OS: HR 0.96, p = 0.59). CONCLUSION: These results question the utility of NLR as a prognostic biomarker in early breast cancer and suggest the lack of correlation of NLR with tumor microenvironment immune response.


Assuntos
Neoplasias da Mama , Linfócitos do Interstício Tumoral , Linfócitos , Neutrófilos , Humanos , Feminino , Neutrófilos/imunologia , Prognóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/sangue , Pessoa de Meia-Idade , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos/metabolismo , Linfócitos/imunologia , Idoso , Adulto , Biomarcadores Tumorais , Estadiamento de Neoplasias , Contagem de Linfócitos
2.
Environ Res ; 252(Pt 3): 118913, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38643821

RESUMO

Exposome studies are advancing in high-income countries to understand how multiple environmental exposures impact health. However, there is a significant research gap in low- and middle-income and tropical countries. We aimed to describe the spatiotemporal variation of the external exposome, its correlation structure between and within exposure groups, and its dimensionality. A one-year follow-up cohort study of 506 children under 5 in two cities in Colombia was conducted to evaluate asthma, acute respiratory infections, and DNA damage. We examined 48 environmental exposures during pregnancy and 168 during childhood in eight exposure groups, including atmospheric pollutants, natural spaces, meteorology, built environment, traffic, indoor exposure, and socioeconomic capital. The exposome was estimated using geographic information systems, remote sensing, spatiotemporal modeling, and questionnaires. The median age of children at study entry was 3.7 years (interquartile range: 2.9-4.3). Air pollution and natural spaces exposure decreased from pregnancy to childhood, while socioeconomic capital increased. The highest median correlations within exposure groups were observed in meteorology (r = 0.85), traffic (r = 0.83), and atmospheric pollutants (r = 0.64). Important correlations between variables from different exposure groups were found, such as atmospheric pollutants and meteorology (r = 0.76), natural spaces (r = -0.34), and the built environment (r = 0.53). Twenty principal components explained 70%, and 57 explained 95% of the total variance in the childhood exposome. Our findings show that there is an important spatiotemporal variation in the exposome of children under 5. This is the first characterization of the external exposome in urban areas of Latin America and highlights its complexity, but also the need to better characterize and understand the exposome in order to optimize its analysis and applications in local interventions aimed at improving the health conditions and well-being of the child population and contributing to environmental health decision-making.


Assuntos
Exposição Ambiental , Expossoma , Humanos , Colômbia/epidemiologia , Pré-Escolar , Feminino , Exposição Ambiental/análise , Masculino , Poluentes Atmosféricos/análise , Gravidez , Poluição do Ar/análise , Estudos de Coortes
3.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474904

RESUMO

During the growing season, olives progress through nine different phenological stages, starting with bud development and ending with senescence. During their lifespan, olives undergo changes in their external color and chemical properties. To tackle these properties, we used hyperspectral imaging during the growing season of the olives. The objective of this study was to develop a lightweight model capable of identifying olives in the hyperspectral images using their spectral information. To achieve this goal, we utilized the hyperspectral imaging of olives while they were still on the tree and conducted this process throughout the entire growing season directly in the field without artificial light sources. The images were taken on-site every week from 9:00 to 11:00 a.m. UTC to avoid light saturation and glitters. The data were analyzed using training and testing classifiers, including Decision Tree, Logistic Regression, Random Forest, and Support Vector Machine on labeled datasets. The Logistic Regression model showed the best balance between classification success rate, size, and inference time, achieving a 98% F1-score with less than 1 KB in parameters. A reduction in size was achieved by analyzing the wavelengths that were critical in the decision making, reducing the dimensionality of the hypercube. So, with this novel model, olives in a hyperspectral image can be identified during the season, providing data to enhance a farmer's decision-making process through further automatic applications.


Assuntos
Algoritmos , Olea , Imageamento Hiperespectral , Máquina de Vetores de Suporte
4.
Int J Mol Sci ; 25(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-39000001

RESUMO

Phenolic compounds with a position ortho to the free phenolic hydroxyl group occupied can be tyrosinase substrates. However, ortho-substituted compounds are usually described as inhibitors. The mechanism of action of tyrosinase on monophenols is complex, and if they are ortho-substituted, it is more complicated. It can be shown that many of these molecules can become substrates of the enzyme in the presence of catalytic o-diphenol, MBTH, or in the presence of hydrogen peroxide. Docking studies can help discern whether a molecule can behave as a substrate or inhibitor of the enzyme. Specifically, phenols such as thymol, carvacrol, guaiacol, eugenol, isoeugenol, and ferulic acid are substrates of tyrosinase, and docking simulations to the active center of the enzyme predict this since the distance of the peroxide oxygen from the oxy-tyrosinase form to the ortho position of the phenolic hydroxyl is adequate for the electrophilic attack reaction that gives rise to hydroxylation occurring.


Assuntos
Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase , Fenóis , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fenóis/química , Fenóis/metabolismo , Especificidade por Substrato , Domínio Catalítico
5.
Int Nurs Rev ; 71(2): 244-249, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38191271

RESUMO

OBJECTIVE: To contribute to the recognition of psychotherapeutic nursing (PTN) as a regulated advanced clinical practice (ACP) in Spain, as is the case in other countries. BACKGROUND: Nurses are continually evolving to improve overall health outcomes. PTN has become a reality, with several authors describing it as an ACP. In Spain, psychotherapy is not officially regulated, which has led to a significant number of psychiatric nurses adopting an important ACP in this area without recognition. SOURCES OF EVIDENCE: Evidence confirms that PTN possesses the attributes necessary to be considered an ACP. Nurses, like psychotherapists, independently address the complex needs of individuals and families within the context of therapeutic relationships, and there is a pressing need to advance formal processes of regulation and certification. DISCUSSION: PTN has evolved at different rates depending on local initiatives, policies and various professional interests. In Spain, it is crucial to evaluate its outcomes, recognise it as an ACP and develop training plans for its regulation and accreditation. CONCLUSIONS: Mental health nurses in Spain have a strong interest in PTN being recognised as an ACP. To this end, they should join forces with other partners, scientific associations and international bodies such as the International Council of Nurses (ICN) to make PTN an internationally recognised ACP. IMPLICATIONS FOR NURSING PRACTICE: Psychotherapeutic nurses could contribute to improving mental health outcomes, client satisfaction and health system efficiency, and their formal recognition is an opportunity to enhance their professional identity, competence and autonomy. IMPLICATIONS FOR NURSING POLICY: Nursing policy needs to be reoriented towards strengthening psychotherapy as an ACP. Synergies and alliances between international nursing associations and the ICN can promote its development and implementation, while research, education and leadership are essential to achieving official regulation and accreditation.


Assuntos
Enfermagem Psiquiátrica , Psicoterapia , Humanos , Espanha , Prática Avançada de Enfermagem , Papel do Profissional de Enfermagem , Promoção da Saúde , Transtornos Mentais/enfermagem , Transtornos Mentais/terapia , Serviços de Saúde Mental/organização & administração , Saúde Mental
6.
Crit Care Med ; 51(8): 992-1000, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36975308

RESUMO

OBJECTIVES: Patients with COVID-19-associated acute respiratory distress syndrome (ARDS) have a high risk for developing acute kidney injury (AKI) which is associated with an increased risk of death and persistent renal failure. Early prediction of AKI is crucial in order to implement preventive strategies. The purpose of this study was to investigate the predictive performance of tissue inhibitor of metalloproteinases 2 and insulin like growth factor binding protein 7 (TIMP-2) × (IGFBP7) in critically ill patients with COVID-19-associated ARDS. DESIGN: Multicenter, prospective, observational study. SETTING: Twelve centers across Europe and United Kingdom. PATIENTS: Patients with moderate or severe COVID-19-associated ARDS were included and serial measurements of (TIMP-2) × (IGFBP7) were performed. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was the development of moderate or severe AKI according to the Kidney Disease: Improving Global Outcomes definition. Three hundred patients were available for the primary analysis, and 39 met the primary endpoint. At enrollment, urinary (TIMP-2) × (IGFBP7) had high predictive value for the primary endpoint with an area under the receiver operating characteristic curve of 0.89 (95% CI, 0.84-0.93). (TIMP-2) × (IGFBP7) was significantly higher in endpoint-positive patients at enrollment and at 12 hours. CONCLUSIONS: Urinary (TIMP-2) × (IGFBP7) predicts the occurrence of AKI in critically ill patients with COVID-19-associated ARDS.


Assuntos
Injúria Renal Aguda , COVID-19 , Humanos , Inibidor Tecidual de Metaloproteinase-2 , Estudos Prospectivos , Estado Terminal , COVID-19/complicações , Biomarcadores , Pontos de Checagem do Ciclo Celular , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina
7.
Environ Sci Technol ; 57(25): 9342-9352, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37294896

RESUMO

Persistent organic pollutants (POPs) are recognized as pollutants of global concern, but so far, information on the trends of legacy POPs in the waters of the world has been missing due to logistical, analytical, and financial reasons. Passive samplers have emerged as an attractive alternative to active water sampling methods as they accumulate POPs, represent time-weighted average concentrations, and can easily be shipped and deployed. As part of the AQUA-GAPS/MONET, passive samplers were deployed at 40 globally distributed sites between 2016 and 2020, for a total of 21 freshwater and 40 marine deployments. Results from silicone passive samplers showed α-hexachlorocyclohexane (HCH) and γ-HCH displaying the greatest concentrations in the northern latitudes/Arctic Ocean, in stark contrast to the more persistent penta (PeCB)- and hexachlorobenzene (HCB), which approached equilibrium across sampling sites. Geospatial patterns of polychlorinated biphenyl (PCB) aqueous concentrations closely matched original estimates of production and use, implying limited global transport. Positive correlations between log-transformed concentrations of Σ7PCB, ΣDDTs, Σendosulfan, and Σchlordane, but not ΣHCH, and the log of population density (p < 0.05) within 5 and 10 km of the sampling sites also supported limited transport from used sites. These results help to understand the extent of global distribution, and eventually time-trends, of organic pollutants in aquatic systems, such as across freshwaters and oceans. Future deployments will aim to establish time-trends at selected sites while adding to the geographical coverage.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Bifenilos Policlorados/análise , Monitoramento Ambiental/métodos , Hexaclorobenzeno/análise , Água Doce , Poluentes Atmosféricos/análise , Praguicidas/análise , Hidrocarbonetos Clorados/análise
8.
Sensors (Basel) ; 23(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37112186

RESUMO

Currently, in many data landscapes, the information is distributed across various sources and presented in diverse formats. This fragmentation can pose a significant challenge to the efficient application of analytical methods. In this sense, distributed data mining is mainly based on clustering or classification techniques, which are easier to implement in distributed environments. However, the solution to some problems is based on the usage of mathematical equations or stochastic models, which are more difficult to implement in distributed environments. Usually, these types of problems need to centralize the required information, and then a modelling technique is applied. In some environments, this centralization may cause an overloading of the communication channels due to massive data transmission and may also cause privacy issues when sending sensitive data. To mitigate this problem, this paper describes a general-purpose distributed analytic platform based on edge computing for distributed networks. Through the distributed analytical engine (DAE), the calculation process of the expressions (that requires data from diverse sources) is decomposed and distributed between the existing nodes, and this allows sending partial results without exchanging the original information. In this way, the master node ultimately obtains the result of the expressions. The proposed solution is examined using three different computational intelligence algorithms, i.e., genetic algorithm, genetic algorithm with evolution control, and particle swarm optimization, to decompose the expression to be calculated and to distribute the calculation tasks between the existing nodes. This engine has been successfully applied in a case study focused on the calculation of key performance indicators of a smart grid, achieving a reduction in the number of communication messages by more than 91% compared to the traditional approach.

9.
Int J Mol Sci ; 24(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37958517

RESUMO

Fibromyalgia (FM) is a multifactorial syndrome, mainly characterized by chronic widespread pain, whose physiopathology is yet to be determined. Reliable biomarkers for FM and how they are associated with the symptomatology have not yet been identified. We aimed to examine the relationships among serum vascular endothelial growth factor (VEGF) and calcitonin gene-related peptide (CGRP) levels with clinical manifestations and pain-related variables in women with FM. We conducted an observational case study with forty-seven women diagnosed with FM. Serum VEGF and CGRP levels were spectrophotometrically analyzed. We used questionnaires to measure the impact of FM and the degree of central sensitization, fatigue, and anxiety. We also assessed pain intensity, electric pain threshold and magnitude, and pressure pain threshold (PPT) in tender points. The linear regression analysis adjusting for age, menopause status, and body mass index showed that serum VEGF levels were significantly associated with the PPTs of non-dominant trapezius (ß = 153.418; p = 0.033), non-dominant second metacarpal (ß = 174.676; p = 0.008) and dominant tibialis anterior (ß = 115.080; p = 0.049) in women with FM. We found no association between serum CGRP levels and the variables measured (p ≥ 0.152). Our results suggest that VEGF may be related to pain processing in patients with FM.


Assuntos
Dor Crônica , Fibromialgia , Humanos , Feminino , Limiar da Dor , Medição da Dor/métodos , Fibromialgia/diagnóstico , Fator A de Crescimento do Endotélio Vascular , Peptídeo Relacionado com Gene de Calcitonina , Dor Crônica/complicações
10.
Int J Mol Sci ; 24(4)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36835205

RESUMO

Myotonic dystrophy type 1 (DM1), the most common form of adult muscular dystrophy, is caused by an abnormal expansion of CTG repeats in the 3' untranslated region of the dystrophia myotonica protein kinase (DMPK) gene. The expanded repeats of the DMPK mRNA form hairpin structures in vitro, which cause misregulation and/or sequestration of proteins including the splicing regulator muscleblind-like 1 (MBNL1). In turn, misregulation and sequestration of such proteins result in the aberrant alternative splicing of diverse mRNAs and underlie, at least in part, DM1 pathogenesis. It has been previously shown that disaggregating RNA foci repletes free MBNL1, rescues DM1 spliceopathy, and alleviates associated symptoms such as myotonia. Using an FDA-approved drug library, we have screened for a reduction of CUG foci in patient muscle cells and identified the HDAC inhibitor, vorinostat, as an inhibitor of foci formation; SERCA1 (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase) spliceopathy was also improved by vorinostat treatment. Vorinostat treatment in a mouse model of DM1 (human skeletal actin-long repeat; HSALR) improved several spliceopathies, reduced muscle central nucleation, and restored chloride channel levels at the sarcolemma. Our in vitro and in vivo evidence showing amelioration of several DM1 disease markers marks vorinostat as a promising novel DM1 therapy.


Assuntos
Distrofia Miotônica , Splicing de RNA , Vorinostat , Adulto , Animais , Humanos , Camundongos , Processamento Alternativo/efeitos dos fármacos , Células Musculares/metabolismo , Músculo Esquelético/metabolismo , Distrofia Miotônica/genética , Splicing de RNA/efeitos dos fármacos , RNA Mensageiro/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Expansão das Repetições de Trinucleotídeos , Vorinostat/metabolismo
11.
J Am Chem Soc ; 144(51): 23275-23279, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36512728

RESUMO

Control of the regioselectivity in the functionalization of C-H bonds of linear alkanes C2H2n+2 via carbene transfer from diazo compounds is restricted to the use of rhodium-based catalysts, which govern the reaction outcome employing donor-acceptor diazo reagents. At variance with that catalyst-controlled strategy, we present an alternative approach in which employing the appropriate silver complexes containing trispyrazolylborate ligands as catalysts with large differences in their steric and electronic properties, the regioselection is mainly governed by the diazo reagent, which leads to the functionalization of primary or secondary sites of linear alkanes (lacking any activating or directing groups). Donor-acceptor aryl diazoacetates exclusively provide the functionalization of the secondary sites of hexane or pentane, whereas acceptor ethyl diazoacetate leads to an unprecedented level of primary functionalization.

12.
J Am Chem Soc ; 144(23): 10608-10614, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35648453

RESUMO

The direct functionalization of Si-H bonds by the nitrene insertion methodology is described. A copper(I) complex bearing a trispyrazolylborate ligand catalyzes the transfer of a nitrene group from PhI═NTs to the Si-H bond of silanes, disilanes, and siloxanes, leading to the exclusive formation of Si-NH moieties in the first example of this transformation. The process tolerates other functionalities in the substrate such as several C-H bonds and alkyne and alkene moieties directly bonded to the silicon center. Density functional theory (DFT) calculations provide a mechanistic interpretation consisting of a Si-H homolytic cleavage and subsequent rebound to the Si-centered radical.


Assuntos
Iminas , Silanos , Aminação , Catálise , Iminas/química , Silanos/química
13.
Crit Care ; 26(1): 130, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534867

RESUMO

BACKGROUND: The detection of coinfections is important to initiate appropriate antimicrobial therapy. Molecular diagnostic testing identifies pathogens at a greater rate than conventional microbiology. We assessed both bacterial coinfections identified via culture or the BioFire® FilmArray® Pneumonia Panel (FA-PNEU) in patients infected with SARS-CoV-2 in the ICU and the concordance between these techniques. METHODS: This was a prospective study of patients with SARS-CoV-2 who were hospitalized for no more than 48 h and on mechanical ventilation for no longer than 24 h in 8 ICUs in Medellín, Colombia. We studied mini-bronchoalveolar lavage or endotracheal aspirate samples processed via conventional culture and the FA-PNEU. Coinfection was defined as the identification of a respiratory pathogen using the FA-PNEU or cultures. Serum samples of leukocytes, C-reactive protein, and procalcitonin were taken on the first day of intubation. We analyzed the empirical antibiotics and the changes in antibiotic management according to the results of the FA-PNEUM and cultures. RESULTS: Of 110 patients whose samples underwent both methods, FA-PNEU- and culture-positive samples comprised 24.54% versus 17.27%, respectively. Eighteen samples were positive in both techniques, 82 were negative, 1 was culture-positive with a negative FA-PNEU result, and 9 were FA-PNEU-positive with negative culture. The two bacteria most frequently detected by the FA-PNEU were Staphylococcus aureus (37.5%) and Streptococcus agalactiae (20%), and those detected by culture were Staphylococcus aureus (34.78%) and Klebsiella pneumoniae (26.08%). The overall concordance was 90.1%, and when stratified by microorganism, it was between 92.7 and 100%. The positive predictive value (PPV) was between 50 and 100% and were lower for Enterobacter cloacae and Staphylococcus aureus. The negative predictive value (NPV) was high (between 99.1 and 100%); MecA/C/MREJ had a specificity of 94.55% and an NPV of 100%. The inflammatory response tests showed no significant differences between patients whose samples were positive and negative for both techniques. Sixty-one patients (55.45%) received at least one dose of empirical antibiotics. CONCLUSIONS: The overall concordance was 90.1%, and it was between 92.7% and 100% when stratified by microorganisms. The positive predictive value was between 50 and 100%, with a very high NPV.


Assuntos
COVID-19 , Coinfecção , Pneumonia , Antibacterianos/uso terapêutico , Bactérias , COVID-19/diagnóstico , Colômbia , Hospitais , Humanos , Unidades de Terapia Intensiva , Reação em Cadeia da Polimerase Multiplex/métodos , Pneumonia/tratamento farmacológico , Estudos Prospectivos , SARS-CoV-2
14.
Molecules ; 27(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35630619

RESUMO

Tyrosinase is the enzyme involved in melanization and is also responsible for the browning of fruits and vegetables. Control of its activity can be carried out using inhibitors, which is interesting in terms of quantitatively understanding the action of these regulators. In the study of the inhibition of the diphenolase activity of tyrosinase, it is intriguing to know the strength and type of inhibition. The strength is indicated by the value of the inhibition constant(s), and the type can be, in a first approximation: competitive, non-competitive, uncompetitive and mixed. In this work, it is proposed to calculate the degree of inhibition (iD), varying the concentration of inhibitor to a fixed concentration of substrate, L-dopa (D). The non-linear regression adjustment of iD with respect to the initial inhibitor concentration [I]0 allows for the calculation of the inhibitor concentration necessary to inhibit the activity by 50%, at a given substrate concentration (IC50), thus avoiding making interpolations between different values of iD. The analytical expression of the IC50, for the different types of inhibition, are related to the apparent inhibition constant (KIapp). Therefore, this parameter can be used: (a) To classify a series of inhibitors of an enzyme by their power. Determining these values at a fixed substrate concentration, the lower IC50, the more potent the inhibitor. (b) Checking an inhibitor for which the type and the inhibition constant have been determined (using the usual methods), must confirm the IC50 value according to the corresponding analytical expression. (c) The type and strength of an inhibitor can be analysed from the study of the variation in iD and IC50 with substrate concentration. The dependence of IC50 on the substrate concentration allows us to distinguish between non-competitive inhibition (iD does not depend on [D]0) and the rest. In the case of competitive inhibition, this dependence of iD on [D]0 leads to an ambiguity between competitive inhibition and type 1 mixed inhibition. This is solved by adjusting the data to the possible equations; in the case of a competitive inhibitor, the calculation of KI1app is carried out from the IC50 expression. The same occurs with uncompetitive inhibition and type 2 mixed inhibition. The representation of iD vs. n, with n=[D]0/KmD, allows us to distinguish between them. A hyperbolic iD vs. n representation that passes through the origin of coordinates is a characteristic of uncompetitive inhibition; the calculation of KI2app is immediate from the IC50 value. In the case of mixed inhibitors, the values of the apparent inhibition constant of meta-tyrosinase (Em) and oxy-tyrosinase (Eox), KI1app and the apparent inhibition constant of metatyrosinase/Dopa complexes (EmD) and oxytyrosinase/Dopa (EoxD), KI2app are obtained from the dependence of iD vs. n, and the results obtained must comply with the IC50 value.


Assuntos
Inibidores Enzimáticos , Monofenol Mono-Oxigenase , Inibidores Enzimáticos/química , Levodopa
15.
J Am Chem Soc ; 143(12): 4837-4843, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33733762

RESUMO

Many transition-metal complexes MLn decompose diazo compounds N2═CR1R2 generating metal-carbenes LnM═CR1R2 which transfer the carbene group to other substrates, constituting an important tool in organic synthesis. All previous reports have shown that the CR1R2 fragment at the metal-carbene remains intact from the parent diazo compound. Herein we report the detection and isolation of a monosubstituted copper carbene where the CR1R2 ligand has undergone a modification from the initial diazo reagent. When TpMsCu(THF) (TpMs = hydrotris(3-mesityl)pyrazolylborate ligand) was reacted with N,N-diethyl diazoacetamide [N2═C(H)(CONEt2)], the stable copper carbene TpMsCu═C(H)(NEt2) was isolated, resulting from a decarbonylation process, with carbon monoxide being trapped as TpMsCu(CO). The simultaneous observation of products derived from the intramolecular carbene insertion reaction into C-H bonds demonstrates that the expected TpMsCu═C(H)(CONEt2) complex is also formed. Experimental data, DFT calculations, and microkinetic models allow us to propose that the latter undergoes CO loss en route to the former.

16.
Crit Care ; 25(1): 63, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588914

RESUMO

BACKGROUND: The identification of factors associated with Intensive Care Unit (ICU) mortality and derived clinical phenotypes in COVID-19 patients could help for a more tailored approach to clinical decision-making that improves prognostic outcomes. METHODS: Prospective, multicenter, observational study of critically ill patients with confirmed COVID-19 disease and acute respiratory failure admitted from 63 ICUs in Spain. The objective was to utilize an unsupervised clustering analysis to derive clinical COVID-19 phenotypes and to analyze patient's factors associated with mortality risk. Patient features including demographics and clinical data at ICU admission were analyzed. Generalized linear models were used to determine ICU morality risk factors. The prognostic models were validated and their performance was measured using accuracy test, sensitivity, specificity and ROC curves. RESULTS: The database included a total of 2022 patients (mean age 64 [IQR 5-71] years, 1423 (70.4%) male, median APACHE II score (13 [IQR 10-17]) and SOFA score (5 [IQR 3-7]) points. The ICU mortality rate was 32.6%. Of the 3 derived phenotypes, the A (mild) phenotype (537; 26.7%) included older age (< 65 years), fewer abnormal laboratory values and less development of complications, B (moderate) phenotype (623, 30.8%) had similar characteristics of A phenotype but were more likely to present shock. The C (severe) phenotype was the most common (857; 42.5%) and was characterized by the interplay of older age (> 65 years), high severity of illness and a higher likelihood of development shock. Crude ICU mortality was 20.3%, 25% and 45.4% for A, B and C phenotype respectively. The ICU mortality risk factors and model performance differed between whole population and phenotype classifications. CONCLUSION: The presented machine learning model identified three clinical phenotypes that significantly correlated with host-response patterns and ICU mortality. Different risk factors across the whole population and clinical phenotypes were observed which may limit the application of a "one-size-fits-all" model in practice.


Assuntos
COVID-19/mortalidade , COVID-19/terapia , Idoso , Análise por Conglomerados , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Medição de Risco , Fatores de Risco , Espanha/epidemiologia
17.
Biotechnol Appl Biochem ; 68(4): 823-831, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32776353

RESUMO

Tyrosinase starts melanogenesis and determines its course, catalyzing the oxidation by molecular oxygen of tyrosine to dopa, and that of dopa to dopaquinone. Then, nonenzymatic coupling reactions lead to dopachrome, which evolves toward melanin. Recently, it has been reported that d-tyrosine acts as tyrosinase inhibitor and depigmenting agent. The action of tyrosinase on the enantiomers of tyrosine (l-tyrosine and d-tyrosine) and dopa (l-dopa and d-dopa) was studied for the first time focusing on quantitative transient phase kinetics. Post-steady-state transient phase studies revealed that l-dopachrome is formed more rapidly than d-dopachrome. This is due to the lower values of Michaelis constants for l-enantiomers than for d-enantiomers, although the maximum rates are equal for both enantiomers. A deeper analysis of the inter-steady-state transient phase of monophenols demonstrated that the enantiomer d-tyrosine causes a longer lag period and a lower steady-state rate, than l-tyrosine at the same concentration. Therefore, d-melanogenesis from d-tyrosine occurs more slowly than does l-melanogenesis from l-tyrosine, which suggests the apparent inhibition of melanin biosynthesis by d-tyrosine. As conclusion, d-tyrosine acts as a real substrate of tyrosinase, with low catalytic efficiency and, therefore, delays the formation of d-melanin.


Assuntos
Di-Hidroxifenilalanina/química , Proteínas Fúngicas/química , Melaninas/síntese química , Monofenol Mono-Oxigenase/química , Tirosina/química , Catálise , Cinética , Melaninas/química , Oxirredução , Estereoisomerismo
18.
Biochem J ; 477(23): 4491-4513, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33146386

RESUMO

Poly(ADP-ribose) polymerase 1 (PARP-1) is a nuclear enzyme that catalyze the transfer of ADP-ribose units from NAD+ to several target proteins involved in cellular stress responses. Using WRL68 (HeLa derivate) cells, we previously showed that PARP-1 activation induced by oxidative stress after H2O2 treatment lead to depletion of cellular NAD+ and ATP, which promoted cell death. In this work, LC-MS/MS-based phosphoproteomics in WRL68 cells showed that the oxidative damage induced by H2O2 increased the phosphorylation of YAP1, a transcriptional co-activator involved in cell survival, and modified the phosphorylation of other proteins involved in transcription. Genetic or pharmacological inhibition of PARP-1 in H2O2-treated cells reduced YAP1 phosphorylation and degradation and increased cell viability. YAP1 silencing abrogated the protective effect of PARP-1 inhibition, indicating that YAP1 is important for the survival of WRL68 cells exposed to oxidative damage. Supplementation of NAD+ also reduced YAP1 phosphorylation, suggesting that the loss of cellular NAD+ caused by PARP-1 activation after oxidative treatment is responsible for the phosphorylation of YAP1. Finally, PARP-1 silencing after oxidative treatment diminished the activation of the metabolic sensor AMPK. Since NAD+ supplementation reduced the phosphorylation of some AMPK substrates, we hypothesized that the loss of cellular NAD+ after PARP-1 activation may induce an energy stress that activates AMPK. In summary, we showed a new crucial role of PARP-1 in the response to oxidative stress in which PARP-1 activation reduced cell viability by promoting the phosphorylation and degradation of YAP1 through a mechanism that involves the depletion of NAD+.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Estresse Oxidativo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células HeLa , Humanos , Peróxido de Hidrogênio/farmacologia , NAD/genética , NAD/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Poli(ADP-Ribose) Polimerase-1/genética , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
19.
Nurs Res ; 70(2): E11-E20, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33630539

RESUMO

BACKGROUND: Fibromyalgia (FM) is a complex syndrome of uncertain etiology, characterized by the presence of widespread pain. Both nitric oxide and enkephalinases modulate pain perception. OBJECTIVES: The aim of this study was to evaluate the relationships among serum nitric oxide levels, oxytocinase activity, and enkephalin-degrading aminopeptidase (EDA) activity with pain-related clinical manifestations in women with FM. METHODS: We performed an observational case study in a population of 58 women diagnosed with FM. Serum nitric oxide levels were analyzed by an ozone chemiluminescence-based assay. Both serum oxytocinase and EDA activities were fluorometrically determined. Pain threshold and pain magnitude were evaluated using the PainMatcher. The pressure pain thresholds were measured using a digital pressure algometer. We used a visual analog scale, the Central Sensitization Inventory, the Revised Fibromyalgia Impact Questionnaire, and the Beck Anxiety Inventory to assess the global level of pain, the symptoms associated with the central sensitization syndrome, the severity of FM, and the anxiety level, respectively. RESULTS: Multiple linear regression analysis adjusted by age, body mass index, and menopause status revealed significant associations between nitric oxide levels and dominant occiput pressure pain thresholds, nondominant occiput pressure pain thresholds, and FM effects. Significant associations of oxytocinase activity with the visual analog scale and dominant knee pressure pain thresholds were also found. Moreover, results showed a significant association between high EDA activity levels and dominant second-rib pressure pain thresholds. DISCUSSION: Our data have shown significant relationships of serum nitric oxide levels and oxytocinase and EDA activities with some body pressure pain thresholds, the daily activity level, and the global intensity of pain in women with FM. These results suggest that pain, which is the main symptom of this syndrome, may be related to alterations in nitric oxide levels and in oxytocinase and EDA activities in patients with FM.


Assuntos
Aminopeptidases/sangue , Fibromialgia/sangue , Óxido Nítrico/sangue , Dor/diagnóstico , Adulto , Feminino , Fibromialgia/complicações , Fibromialgia/fisiopatologia , Humanos , Pessoa de Meia-Idade , Dor/sangue , Dor/etiologia , Medição da Dor , Limiar da Dor , Índice de Gravidade de Doença
20.
J Therm Biol ; 95: 102813, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33454042

RESUMO

BACKGROUND: Fibromyalgia syndrome is defined as a complex disease, characterized by chronic widespread musculoskeletal pain and other symptoms. The factors underlying physiopathology of fibromyalgia are not well understood, complicating its diagnosis and management. OBJECTIVES: To evaluate the peripheral vascular blood flow of the skin of the hands and the core body temperature as indirect measures of sympathetic adrenergic activity of the nervous system and its relationship to nitric oxide levels (NO) in women with fibromyalgia compared with healthy controls. METHODS: Forty-two women with fibromyalgia and 52 healthy women were enrolled in this observational pilot study. We used infrared thermography of the hands and an infrared dermal thermometer to evaluate the peripheral vascular blood flow and tympanic and axillary core body temperature, respectively. We measured NO levels using the ozone chemiluminescence-based method. RESULTS: Two-way analysis of covariance (ANCOVA) showed that the tympanic (P=0.002) and hand temperatures were significantly higher in the patients with fibromyalgia than in the controls (P≤0.001). Significant associations were also found between serum NO levels and minimum temperatures at the dorsal center of the dominant hand (ß=-3.501; 95% confidence interval [CI] -6.805, ­0.198; P= 0.038), maximum temperature (ß=-5.594; 95% CI ­10.106, ­1.081; P=0.016), minimum temperature (ß=-4.090; 95% CI ­7.905, ­0.275; P=0.036), and mean temperature (ß=-5.519; 95% CI ­9.933, ­1.106; P=0.015) of the center of the palm of the non-dominant hand, maximum temperature at the thenar eminence of the dominant hand (ß=-5.800; 95% CI ­10.508, ­1.092; P=0.017), and tympanic temperature (ß=-9.321; 95% CI ­17.974, ­0.669; P=0.035) in the controls. CONCLUSIONS: Our findings indicate that the women with fibromyalgia showed higher tympanic core body and hand temperature than the healthy controls. Moreover, there were negative associations between hand peripheral vasodilation and NO in the healthy women but not in those with fibromyalgia, suggesting a dysfunction of sympathetic cutaneous neural control.


Assuntos
Fibras Adrenérgicas/fisiologia , Temperatura Corporal , Fibromialgia/fisiopatologia , Óxido Nítrico/metabolismo , Pele/irrigação sanguínea , Sistema Nervoso Simpático/fisiopatologia , Idoso , Feminino , Fibromialgia/metabolismo , Mãos/irrigação sanguínea , Mãos/inervação , Humanos , Microvasos/inervação , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Pele/inervação , Termografia
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