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1.
Nature ; 617(7959): 111-117, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37100901

RESUMO

Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, [Formula: see text]50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3-5, little is known about how these vary across Earth's largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters [Formula: see text]50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both [Formula: see text]50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth-mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink.


Assuntos
Carbono , Florestas , Árvores , Clima Tropical , Biomassa , Carbono/metabolismo , Secas , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Xilema/metabolismo , Chuva , Mudança Climática , Sequestro de Carbono , Estresse Fisiológico , Desidratação
2.
Phys Chem Chem Phys ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39086219

RESUMO

In the solvent extraction of rare earth elements, mechanistic aspects remain unclear regarding where and how extractant molecules coordinate metal ions and transport them from the aqueous phase into the organic phase. Molecular dynamics simulations were used to examine how unprotonated di(2-ethylhexyl)phosphoric acid (DEHP-) ligands that coordinate the Gd3+ ion can transfer the ion across the water-organic interface. Using the umbrella sampling technique, potential of mean force profiles were constructed to quantify the relative solubility of the Gd3+ ion coordinated to 0-3 DEHP- ligands in either water, 1-octanol, or hexane solvents and at the water-organic interfaces. The simulations show the Gd-DEHP- complexes, at varying Ln-ligand ratios, preferentially solvate on water-organic interfaces. While the Gd(DEHP-)3 complex will diffuse past the aqueous-organic interface into the octanol solvent, it is thermodynamically preferred for the Gd(DEHP-)3 complex to remain in the water-hexane interface when there is no amphiphilic layer of excess ligand.

3.
Am J Drug Alcohol Abuse ; 50(2): 162-172, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38284925

RESUMO

Background: Phosphatidylethanol (PEth) is a blood-based biomarker for alcohol consumption that can be self-collected and has high sensitivity, specificity, and a longer detection window compared to other alcohol biomarkers.Objectives: We evaluated the feasibility and acceptability of a telehealth-based contingency management (CM) intervention for alcohol use disorder (AUD) using the blood-based biomarker PEth to assess alcohol consumption.Methods: Sixteen adults (7 female, 9 male) with AUD were randomized to Control or CM conditions. Control participants received reinforcers regardless of their PEth levels. CM participants received reinforcers for week-to-week decreases in PEth (Phase 1) or maintenance of PEth consistent with abstinence (<20 ng/mL, Phase 2). Blood samples were self-collected using the TASSO-M20 device. Acceptability was assessed by retention in weeks. Satisfaction was assessed with the Client Satisfaction Questionnaire (CSQ-8) and qualitative interviews. The primary efficacy outcome was PEth-defined abstinence. Secondary outcomes included the proportion of visits with PEth-defined heavy alcohol consumption, negative urine ethyl glucuronide results, and self-reported alcohol use.Results: Retention averaged 18.6 ± 8.8 weeks for CM participants. CM participants reported high levels of satisfaction (CSQ-8, Mean = 30.3 ± 1.5). Interview themes included intervention positives, such as staff support, quality of life improvement, and accountability. 72% of PEth samples from CM participants were consistent with abstinence versus 34% for Control participants (OR = 5.0, p = 0.007). PEth-defined heavy alcohol consumption was detected in 28% of CM samples and 52% of Control samples (OR = 0.36, p = 0.159). CM participants averaged 1.9 ± 1.7 drinks/day versus 4.2 ± 6.3 for Control participants (p = 0.304).Conclusion: Results support the acceptability and satisfaction of a telehealth PEth-based CM intervention, though a larger study is needed to assess its efficacy [NCT04038021].


Assuntos
Alcoolismo , Biomarcadores , Estudos de Viabilidade , Glicerofosfolipídeos , Telemedicina , Humanos , Feminino , Masculino , Telemedicina/métodos , Glicerofosfolipídeos/sangue , Projetos Piloto , Pessoa de Meia-Idade , Adulto , Biomarcadores/sangue , Alcoolismo/terapia , Consumo de Bebidas Alcoólicas/terapia , Satisfação do Paciente , Terapia Comportamental/métodos
4.
Rev Esp Enferm Dig ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345488

RESUMO

We present the case of a 26-year-old male patient with no history of interest who consulted the emergency department due to occlusive symptoms. Urgent CT showed the presence of a transverse colonic volvulus in the context of a heterotopic liver, located in the left hypochondrium. There were no clinical or radiological signs of perforation or ischemia, so urgent endoscopic decompression was performed with subsequent elective surgery with a favorable resolution of the condition. Transverse colonic volvulus is rare (<1%) and wandering liver is an exceptional predisposing factor, with less than a hundred published cases. In these patients, endoscopic decompression carries a risk of perforation with high recurrence rates, and surgical treatment should be considered. However, in this case, in the absence of severity criteria, decompressive colonoscopy was considered an urgent treatment and subsequent elective surgery with favorable results.

5.
Appl Environ Microbiol ; 89(6): e0036723, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37272802

RESUMO

Acetyl-CoA synthetase (ACS) and acetate ligase (ACD) are widespread among microorganisms, including archaea, and play an important role in their carbon metabolism, although only a few of these enzymes have been characterized. Anaerobic methanotrophs (ANMEs) have been reported to convert methane anaerobically into CO2, polyhydroxyalkanoate, and acetate. Furthermore, it has been suggested that they might be able to use acetate for anabolism or aceticlastic methanogenesis. To better understand the potential acetate metabolism of ANMEs, we characterized an ACS from ANME-2a as well as an ACS and an ACD from ANME-2d. The conversion of acetate into acetyl-CoA (Vmax of 8.4 µmol mg-1 min-1 and Km of 0.7 mM acetate) by the monomeric 73.8-kDa ACS enzyme from ANME-2a was more favorable than the formation of acetate from acetyl-CoA (Vmax of 0.4 µmol mg-1 min-1 and Km of 0.2 mM acetyl-CoA). The monomeric 73.4-kDa ACS enzyme from ANME-2d had similar Vmax values for both directions (Vmax,acetate of 0.9 µmol mg-1 min-1 versus Vmax,acetyl-CoA of 0.3 µmol mg-1 min-1). The heterotetrameric ACD enzyme from ANME-2d was active solely in the acetate-producing direction. Batch incubations of an enrichment culture dominated by ANME-2d fed with 13C2-labeled acetate produced 3 µmol of [13C]methane in 7 days, suggesting that this anaerobic methanotroph might have the potential to reverse its metabolism and perform aceticlastic methanogenesis using ACS to activate acetate albeit at low rates (2 nmol g [dry weight]-1 min-1). Together, these results show that ANMEs may have the potential to use acetate for assimilation as well as to use part of the surplus acetate for methane production. IMPORTANCE Acetyl-CoA plays a key role in carbon metabolism and is found at the junction of many anabolic and catabolic reactions. This work describes the biochemical properties of ACS and ACD enzymes from ANME-2 archaea. This adds to our knowledge of archaeal ACS and ACD enzymes, only a few of which have been characterized to date. Furthermore, we validated the in situ activity of ACS in ANME-2d, showing the conversion of acetate into methane by an enrichment culture dominated by ANME-2d.


Assuntos
Acetatos , Archaea , Archaea/metabolismo , Acetilcoenzima A/metabolismo , Anaerobiose , Oxirredução , Acetatos/metabolismo , Carbono/metabolismo , Metano/metabolismo
6.
Blood ; 137(1): 49-60, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-32693406

RESUMO

Patients with multiple myeloma (MM) carrying standard- or high-risk cytogenetic abnormalities (CAs) achieve similar complete response (CR) rates, but the later have inferior progression-free survival (PFS). This questions the legitimacy of CR as a treatment endpoint and represents a biological conundrum regarding the nature of tumor reservoirs that persist after therapy in high-risk MM. We used next-generation flow (NGF) cytometry to evaluate measurable residual disease (MRD) in MM patients with standard- vs high-risk CAs (n = 300 and 90, respectively) enrolled in the PETHEMA/GEM2012MENOS65 trial, and to identify mechanisms that determine MRD resistance in both patient subgroups (n = 40). The 36-month PFS rates were higher than 90% in patients with standard- or high-risk CAs achieving undetectable MRD. Persistent MRD resulted in a median PFS of âˆ¼3 and 2 years in patients with standard- and high-risk CAs, respectively. Further use of NGF to isolate MRD, followed by whole-exome sequencing of paired diagnostic and MRD tumor cells, revealed greater clonal selection in patients with standard-risk CAs, higher genomic instability with acquisition of new mutations in high-risk MM, and no unifying genetic event driving MRD resistance. Conversely, RNA sequencing of diagnostic and MRD tumor cells uncovered the selection of MRD clones with singular transcriptional programs and reactive oxygen species-mediated MRD resistance in high-risk MM. Our study supports undetectable MRD as a treatment endpoint for patients with MM who have high-risk CAs and proposes characterizing MRD clones to understand and overcome MRD resistance. This trial is registered at www.clinicaltrials.gov as #NCT01916252.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Neoplasia Residual/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Compostos de Boro/uso terapêutico , Bortezomib/uso terapêutico , Aberrações Cromossômicas , Dexametasona/uso terapêutico , Feminino , Citometria de Fluxo , Glicina/análogos & derivados , Glicina/uso terapêutico , Humanos , Lenalidomida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Resultado do Tratamento
7.
Pediatr Res ; 94(5): 1754-1763, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37280325

RESUMO

BACKGROUND: This study provides reference values for cardiovascular modulation at rest, during maximal exercise test and recovery after exercise in Caucasian children according to weight status and cardiorespiratory fitness (CRF) level. Additionally, the current study analyzed several correlations between autonomic cardiovascular modulation, cardiorespiratory performance and cardiometabolic risk. The principal goal of this study was to analyze cardiac function at rest, during maximum exercise, and during the recovery phase in children grouped according to weight status and CRF level. METHODS: One hundred and fifty-two healthy children (78 girls) 10-16 years of age were divided into three groups: soccer and basketball players (SBG), endurance group (EG), and sedentary people with overweight and obesity (OOG). A cardiac RR interval monitor recorded the cardiac data and specific software analyzed the cardiac autonomic response through heart rate (HR) and HR variability. The study analyzed resting HR (RHR), HRpeak, and HR recovery (HRR). RESULTS: OOG showed significant poorer performance in the Léger test lower V̇O2 max and higher values of blood pressure at rest and post-exercise than sport groups. The EG presented the best results in CRF and cardiometabolic risk (CMR) in relation to SBG and OOG. The OOG showed higher percentage of HR values, compatible with an unhealthy cardiovascular autonomic modulation than the sport groups, with significant differences in bradycardia, HR reserve, and HRR 5 min. CONCLUSIONS: Aerobic performance, vagal activity, blood pressure, chronotropic competence, and HRR have significant associations with CMR parameters. IMPACT: The current study presents reference values of autonomic cardiac function in Caucasian children according to weight status and cardiorespiratory fitness level. Aerobic performance, vagal activity, blood pressure, chronotropic competence, and heart rate during the recovery period after exercise have significant associations with cardiometabolic risk parameters. Children with overweight and obesity show signs of autonomic dysfunction reflected as low cardiac vagal activity and poor chronotropic competence.


Assuntos
Sobrepeso , Aptidão Física , Feminino , Humanos , Criança , Aptidão Física/fisiologia , Teste de Esforço/métodos , Obesidade , Pressão Sanguínea , Frequência Cardíaca/fisiologia , Bradicardia
8.
Med Mycol ; 61(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37944000

RESUMO

Fusarium species represent an opportunistic fungal pathogen. The data in Mexico about Fusarium infections in humans are scarce. Here, we present a retrospective series of patients with a confirmed diagnosis of fusariosis in eight different hospitals in Mexico from January 2010 to December 2019. The diagnosis of proven fusariosis was made according to the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium (EORT/MSG) criteria. A total of 49 cases were identified in our series. Most patients had burn injuries (49%), and 37% had hematological malignancies. Most patients had fire injuries (40%), followed by electric injuries (8%), febrile neutropenia (10%), and pancytopenia (6%). Patients had skin and soft tissue involvement in 49%, followed by blood culture isolation and biopsies from different sites of the body (lung, sinuses, bone tissue, and eyes). Febrile neutropenia (10%) and fungemia (8%) were the most common clinical syndromes in immunosuppressed patients. Most patients received monotherapy (67%), where voriconazole was used in 30% of the cases, followed by conventional amphotericin B (16%), and lipidic formulations of amphotericin B in 10% (either liposomal amphotericin B or amphotericin B lipid complex). Combination therapy was used in 20% of the cases, and the most common combination therapy was triazole plus any lipidic formulation of amphotericin B (10%). Mortality related to Fusarium infection occurred in 22% of patients. Fusariosis is a serious threat. Burn injuries and hematologic malignancies represent the most common causes of infection in this small series from Mexico.


This study describes the epidemiological characteristics of patients with fusariosis from a multicenter cohort in Mexico. These findings provide information from this invasive fungal disease that threatens different countries in Latin America.


Assuntos
Queimaduras , Neutropenia Febril , Fusariose , Fusarium , Neoplasias Hematológicas , Humanos , Fusariose/tratamento farmacológico , Fusariose/epidemiologia , Fusariose/veterinária , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Estudos Retrospectivos , México/epidemiologia , Voriconazol/uso terapêutico , Neoplasias Hematológicas/veterinária , Queimaduras/complicações , Queimaduras/epidemiologia , Queimaduras/veterinária , Neutropenia Febril/tratamento farmacológico , Neutropenia Febril/veterinária
9.
Environ Res ; 216(Pt 2): 114483, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36209790

RESUMO

Personal exposimeters are currently used in studies assessing human exposure to electromagnetic fields. These devices are usually carried by an individual, but vehicles such as bicycle or car are also used. The aim of the present study was to propose a personal exposimeter attached to a drone to perform environmental radio-frequency measurements. Trials were carried out to determine whether: (i) the wireless communication between the remote controller and the drone affects the downlink mobile telephony bands by a cross-talk effect, and (ii) the structure of the drone alters the measurements of the exposimeter compared to when the meter is on a tripod. To apply this system to a real scenario, a 3D representation of the electric field in a building was obtained, and the attenuation due to the building of radiation from outside was estimated. Measurements of the electromagnetic field with this system will make it possible to monitor without risk the emissions of antennas in their close vicinity, and to validate propagation models experimentally.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Humanos , Dispositivos Aéreos não Tripulados , Exposição Ambiental , Ondas de Rádio
10.
Bull Math Biol ; 85(7): 68, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37310552

RESUMO

Homogeneity across lineages is a general assumption in phylogenetics according to which nucleotide substitution rates are common to all lineages. Many phylogenetic methods relax this hypothesis but keep a simple enough model to make the process of sequence evolution more tractable. On the other hand, dealing successfully with the general case (heterogeneity of rates across lineages) is one of the key features of phylogenetic reconstruction methods based on algebraic tools. The goal of this paper is twofold. First, we present a new weighting system for quartets (ASAQ) based on algebraic and semi-algebraic tools, thus especially indicated to deal with data evolving under heterogeneous rates. This method combines the weights of two previous methods by means of a test based on the positivity of the branch lengths estimated with the paralinear distance. ASAQ is statistically consistent when applied to data generated under the general Markov model, considers rate and base composition heterogeneity among lineages and does not assume stationarity nor time-reversibility. Second, we test and compare the performance of several quartet-based methods for phylogenetic tree reconstruction (namely QFM, wQFM, quartet puzzling, weight optimization and Willson's method) in combination with several systems of weights, including ASAQ weights and other weights based on algebraic and semi-algebraic methods or on the paralinear distance. These tests are applied to both simulated and real data and support weight optimization with ASAQ weights as a reliable and successful reconstruction method that improves upon the accuracy of global methods (such as neighbor-joining or maximum likelihood) in the presence of long branches or on mixtures of distributions on trees.


Assuntos
Conceitos Matemáticos , Modelos Biológicos , Filogenia , Nucleotídeos
11.
BMC Geriatr ; 23(1): 182, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991396

RESUMO

BACKGROUND: Polyphenols have been shown to be effective against many chronic diseases, including neurodegenerative diseases. Specifically, the consumption of raisins, being a food rich in polyphenols, has been attributed with neuroprotective benefits. Therefore, our main objective is to evaluate the effect of including 50 g of raisins in the diet daily for 6 months, on the improvement of cognitive performance, cardiovascular risk factors and markers of inflammation in a population of older adults without cognitive impairment. METHODS: Design and intervention: This study will be a randomized controlled clinical trial of two parallel groups. Each subject included in the study will be randomly assigned to one of two study groups: control group (no supplement), intervention group (50 g of raisins daily during 6 months). STUDY POPULATION: The participants will be selected by consecutive sampling in the Primary Care consultations of urban health centers in Salamanca and Zamora (Spain), taking into account the selection criteria. STUDY VARIABLES: Two visits will be made, baseline and at 6 months. Cognitive performance will be evaluated (Mini-Mental State Examination test, Rey Auditory Verbal Learning Test, verbal fluency and montreal cognitive assessment (Moca)). It will also be analyzed the level of physical activity, quality of life, activities of daily living, energy and nutritional composition of the diet, body composition, blood pressure, heart rate, markers of inflammation and other laboratory tests of clinical relevance (glycaemia, total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides). In addition, sociodemographic data, personal and family history, medication use and alcohol and tobacco consumption will be collected. DISCUSSION: In this project, it is intended to contribute to minimize the problems derived from cognitive deterioration in older people. TRIAL REGISTRATION: ClincalTrials.gov Identifier: NCT04966455 Registration date: July 1, 2021.


Assuntos
Disfunção Cognitiva , Vitis , Humanos , Idoso , Qualidade de Vida , Polifenóis , Atividades Cotidianas , Cognição , Suplementos Nutricionais , Inflamação , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Pediatr Dermatol ; 40(3): 537-539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36394113

RESUMO

We report the case of a neonate presenting with the clinical features of blueberry muffin syndrome caused by ganglioneuroblastoma, a rare variant of neuroblastoma. This syndrome may be the only visible manifestation of a neonatal tumor and highlights the importance of early recognition and initiation of therapy to reduce mortality.


Assuntos
Ganglioneuroblastoma , Recém-Nascido , Lactente , Humanos , Síndrome
13.
Mycopathologia ; 188(1-2): 35-49, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36515766

RESUMO

Invasive infections caused by filamentous fungi have increased considerably due to the alteration of the host's immune response. Aspergillus terreus is considered an emerging pathogen and has shown resistance to amphotericin B treatment, resulting in high mortality. The development of fungal biofilm is a virulence factor, and it has been described in some cases of invasive aspergillosis. In addition, although the general composition of fungal biofilms is known, findings related to biofilms of a lipid nature are rarely reported. In this study, we present the identification of a clinical strain of A. terreus by microbiological and molecular tools, also its in vitro biofilm development capacity: (i) Biofilm formation was quantified by Crystal Violet and reduction of tetrazolium salts assays, and simultaneously the stages of biofilm development were described by Scanning Electron Microscopy in High Resolution (SEM-HR). (ii) Characterization of the organizational structure of the biofilm was performed by SEM-HR. The hyphal networks developed on the surface, the abundant air channels created between the ECM (extracellular matrix) and the hyphae fused in anastomosis were described. Also, the presence of microhyphae is reported. (iii) The chemical composition of the ECM was analyzed by SEM-HR and CLSM (Confocal Laser Scanning Microscopy). Proteins, carbohydrates, nucleic acids and a relevant presence of lipid components were identified. Some structures of apparent waxy appearance were highlighted by SEM-HR and backscatter-electron diffraction, for which CLSM was previously performed. To our knowledge, this work is the first description of a lipid-type biofilm in filamentous fungi, specifically of the species A. terreus from a clinical isolate.


Assuntos
Aspergillus , Biofilmes , Fungos , Encéfalo , Lipídeos
14.
J Dtsch Dermatol Ges ; 21(7): 741-748, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37218533

RESUMO

BACKGROUND AND OBJECTIVES: Melanoma differentiation-associated gene 5 antibody (anti-MDA5) in dermatomyositis (DM) is associated with rapidly progressive interstitial lung disease and poor prognosis. Early diagnosis is key to improving the prognosis of these patients. The aim was to confirm cutaneous characteristics in patients with anti-MDA5 dermatomyositis and to explore new diagnostic markers for the presence of anti-MDA5 (anti-MDA5+ ). PATIENTS AND METHODS: A multicenter cross-sectional retrospective cohort study of 124 patients diagnosed with DM, of which 37 were anti-MDA5+ . Demographic data, laboratory data, and clinical manifestations were collected. RESULTS: Anti-MDA5+ DM is characterized by a distinct mucocutaneous phenotype that includes oral lesions, alopecia, mechanic's hands, palmar and dorsal papules, palmar erythema, vasculopathy, and skin ulceration. We found vasculopathy and digit tip involvement very frequently in anti-MDA5+ patients (p <0.001), being a diagnostic marker of anti-MDA5+ (OR, 12.355; 95% CI 2.850-79.263; p  =  0.012 and OR, 7.447; 95% CI 2.103-46.718; p  =  0.004, respectively). The presence of ulcers deserves special mention, especially in anti-MDA5+ patients, because in our cohort, up to 97% of the anti-MDA5+ patients had ulcers. CONCLUSIONS: In patients with suspected DM with digit tip involvement or vasculopathy, the presence of anti-MDA5 antibodies must be ruled out, as it may be a clinical predictor.


Assuntos
Dermatomiosite , Humanos , Estudos Retrospectivos , Helicase IFIH1 Induzida por Interferon , Úlcera , Estudos Transversais , Autoanticorpos , Prognóstico
15.
Environ Monit Assess ; 195(7): 889, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365432

RESUMO

Mining is one of the principal economic activities in Mexico, which in addition to bringing benefits to the population, causes health and environmental problems. This activity produces a lot of wastes, but the main one is tailings. In Mexico, these wastes are disposed of in the open air, and there is no control over them, so the particles of these wastes are dispersed by wind currents to the surrounding population. In this research, tailings were characterized, finding in them particles smaller than 100 microns; in this way, tailings can enter into the respiratory system and hence can cause diseases. Furthermore, it is important to identify the toxic components. The present work does not have previous research in Mexico, and it shows a qualitative characterization of the tailings from an active mine using different analytical techniques. In addition to the data obtained from the characterization of the tailings, as well as the concentration of the toxic elements found, which were Pb and As, a dispersal model was generated and used to estimate the concentration of particles in the wind generated at the studied area. The air quality model used in this research is AERMOD, where it uses emission factors and available databases provided by Environmental Protection Agency (USEPA); Moreover, the model was coupled with meteorological information from the latest generation WRF model. The modeling results estimated that the dispersion of particles from the tailings dam can contribute up to 10.15 µg/m3 of PM10 to the air quality of the site, which, according to the characterization of the samples obtained, could be dangerous for human health and can be estimated up to a concentration of 0.04 µg/m3 of Pb and 10.90 ng/m3 of As. It is very important to make this kind of research to know the risk which people around this disposal sites are exposed to.


Assuntos
Monitoramento Ambiental , Chumbo , Estados Unidos , Humanos , Monitoramento Ambiental/métodos , Vento , México
16.
Biophys J ; 121(16): 3034-3048, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842753

RESUMO

Ascaphins are cationic antimicrobial peptides that have been shown to have potential in the treatment of infectious diseases caused by multidrug-resistant pathogens (MDR). However, to date, their principal molecular target and mechanism of action are unknown. Results from peptide prediction software and molecular dynamics simulations confirmed that ascaphin-8 is an alpha-helical peptide. For the first time, the peptide was described as membranotrophic using biophysical approaches including calcein liposome leakage, Laurdan general polarization, and dynamic light scattering. Ascaphin-8's activity and selectivity were modulated by rearranging the spatial distribution of lysine (Var-K5), aspartic acid (Var-D4) residues, or substitution of phenylalanine with tyrosine (Var-Y). The parental peptide and its variants presented high affinity toward the bacterial membrane model (≤2 µM), but lost activity in sterol-enriched membranes (mammal and fungal models, with cholesterol and ergosterol, respectively). The peptide-induced pore size was estimated to be >20 nm in the bacterial model, with no difference among peptides. The same pattern was observed in membrane fluidity (general polarization) assays, where all peptides reduced membrane fluidity of the bacterial model but not in the models containing sterols. The peptides also showed high activity toward MDR bacteria. Moreover, peptide sensitivity of the artificial membrane models compared with pathogenic bacterial isolates were in good agreement.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Fluidez de Membrana , Animais , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias , Colesterol/química , Mamíferos , Testes de Sensibilidade Microbiana , Esteróis/química
17.
Eur J Clin Invest ; 52(2): e13684, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34582566

RESUMO

INTRODUCTION: The aim of this work was to analyse the association of the retinal arteriolar calibre and the arteriole/venule index (AV index) with vascular ageing in a general population without previous cardiovascular disease. MATERIALS AND METHODS: Descriptive cross-sectional study. A total of 482 individuals without cardiovascular disease (mean age: 55.6 ± 14.2 years) were selected by random sampling, stratified by age and sex. The retinal arteriolar calibre was measured using digital fundus images of the back of the eye captured with a validated, semiautomatized and computer-assisted software (Index calculator). Vascular ageing was defined using three criteria based on the values of: (1) Carotid-femoral Pulse Wave Velocity (cfPWV), (2) Brachial-ankle Pulse Wave Velocity (baPWV) and (3) Carotid Intima-Media Thickness. RESULTS: The AV index and arteriolar calibre show a negative correlation with age, arterial pressure, cardiovascular risk and parameters of vascular structure and function (p < 0.001 in all cases). We found lower mean values of the AV index and arteriolar calibre in the individuals with early vascular ageing compared to those with healthy vascular ageing. AV index was negatively correlated with cfPWV ((ß=-2.9; 95% CI (-4.7; -1.1)), baPWV ((ß=-3.2; 95% CI (-5.4; -0.9)) and vascular ageing index ((ß=-1.7; 95% CI (-2.7; -0.7)). Arteriolar calibre showed a negative correlation with baPWV (ß=-0.1; 95% CI (-0.2; -0.1)). In the logistic regression analysis, lower values of AV index ((OR=0.01; 95% CI (0.01-0.10), OR=0.03; 95% CI (0.01-0.11) and OR=0.09; 95% CI (0.01-0.67)) were associated with EVA defined with cfPWV, baPWV and vascular ageing index respectively, and lower values of arteriolar calibre ((OR=0.71; 95% CI (0.55-0.91)) were associated with EVA defined with vascular ageing index. CONCLUSIONS: Lower values of AV index and retinal arteriolar calibre were associated with vascular ageing in a general Spanish population without previous cardiovascular disease.


Assuntos
Envelhecimento , Vasos Sanguíneos/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Vasos Retinianos/anatomia & histologia , Adulto , Idoso , Arteríolas/anatomia & histologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Espanha , Vênulas/anatomia & histologia
18.
Ann Hematol ; 101(1): 59-67, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34642787

RESUMO

Despite the effectiveness of plasma exchange (PEX) and immunosuppressants in the treatment of acquired thrombotic thrombocytopenic purpura (aTTP), a number of patients still die as a result of the disease. Whether caplacizumab could rescue these patients remains still unsettled. The objective of this study was to characterise mortality patterns and prognostic factors in the first episode of aTTP.We queried the Spanish TTP Registry for patients with a diagnosis of aTTP in their presenting episode who fulfilled complete clinical and follow-up data (n = 102). The patients were diagnosed between 2004 and 2018, and all were treated with daily PEX and corticosteroids. Clinical and laboratory data were analysed at diagnosis and during the treatment course.Eight patients (7.7%) died between 12 h and 36 days after presentation, and could be classified into three patterns: death before treatment, early death driven by acute cardiac or neurologic events, and late death due to unremitted aTTP. Stupor or coma at diagnosis and platelet count < 20 × 109 /L by the 6th treatment day were independently associated with increased risk of death.Stupor or coma at diagnosis and lack of response to PEX by the 6th day in patients experiencing the first episode of aTTP are strong predictors of mortality. These patients could be rescued by novel agents aimed at halting the microvascular thrombosis until adequate immunosuppression is achieved.


Assuntos
Corticosteroides/uso terapêutico , Troca Plasmática , Púrpura Trombocitopênica Trombótica/mortalidade , Púrpura Trombocitopênica Trombótica/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Púrpura Trombocitopênica Trombótica/diagnóstico , Anticorpos de Domínio Único/uso terapêutico
19.
Pediatr Res ; 92(2): 526-535, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34718350

RESUMO

BACKGROUND: Heart rate (HR) is a biomarker used to measure physiological function, health status and cardiovascular autonomic function. The purpose of this study was to determine sex- and age-specific reference values for cardiac autonomic function at rest, during maximal exercise and the recovery phase in prepubertal children. METHODS: Five hundred and twelve healthy children 7-11 years of age performed a Léger test. A heart RR-interval monitor recorded the heart data and a specific software analysed the cardiac autonomic response through HR and HR variability (HRV). It analysed HR before the test (resting HR, RHR), during the test (HRpeak) and HR recovery (HRR) in the first minute (HRR1) and the fifth minute (HRR5). The values are mean ± SD. RESULTS: Collectively, 91.2% of girls and 92.3% of boys were within the recommended ranges regarding RHR. The average HRpeak was 199 ± 10.83 b.p.m. and 96.8% of girls and 95.3% of boys were within the minimum threshold value recommended (180 b.p.m.). Boys showed lower values of RHR than girls (p < 0.001) and larger values of HRR 1 and HRR5 (p < 0.001). CONCLUSIONS: This study comprehensively provides a reference set of data for the most important HR variables that can be obtained during exercise testing in prepubertal children regarding age and sex and in a field setting. IMPACT: This is the first study to provide reference values of autonomic cardiac function at rest, during maximal exercise and during the recovery period in prepubertal children aged 7-11 years. Despite the early age of participants, cardiorespiratory fitness, RHR and HRR are different according to sex. Aerobic performance and HRpeak have a negative correlation with body mass index and cardiometabolic risk.


Assuntos
Aptidão Cardiorrespiratória , Exercício Físico , Sistema Nervoso Autônomo , Criança , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino
20.
Appetite ; 169: 105821, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808273

RESUMO

Sensory specific satiety refers to a decline in the hedonic value of the sensory properties of a particular food as it is consumed. This phenomenon is characterized by a decrement in responding as a consequence of repeated exposure, is stimulus specific, and recovers after time. All these characteristics are shared with the habituation phenomenon and for this reason, habituation has been proposed as the underlying mechanism that explains this eating regulatory system. However, several studies conducted with human models have yielded mixed results. Using rats as experimental subjects, the present study tested the following three characteristics of habituation within a Sensory Specific Satiety (SSS) framework: spontaneous recovery, dishabituation and the distractor effect. Experiment 1 demonstrated the basic effect of SSS and its spontaneous recovery over time. In Experiment 2 we found that the presentation of a dishabituator after a pre-feeding procedure had no impact on the SSS effect. Finally, in Experiment 3 the presence of a distractor during a pre-feeding procedure did not alter the expression of SSS. These results challenge the idea that SSS constitutes a typical case of habituation, at least with the procedure used here.


Assuntos
Habituação Psicofisiológica , Paladar , Animais , Ratos , Saciação
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