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1.
Nature ; 589(7843): 527-531, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33505036

RESUMO

The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include the electron spin, the relativistic and quantum field effects, and tiny energy shifts related to the complex structure of the nucleus. These energy shifts caused by the nuclear structure are vastly magnified in hydrogen-like systems formed by a negative muon and a nucleus, so spectroscopy of these muonic ions can be used to investigate the nuclear structure with high precision. Here we present the measurement of two 2S-2P transitions in the muonic helium-4 ion that yields a precise determination of the root-mean-square charge radius of the α particle of 1.67824(83) femtometres. This determination from atomic spectroscopy is in excellent agreement with the value from electron scattering1, but a factor of 4.8 more precise, providing a benchmark for few-nucleon theories, lattice quantum chromodynamics and electron scattering. This agreement also constrains several beyond-standard-model theories proposed to explain the proton-radius puzzle2-5, in line with recent determinations of the proton charge radius6-9, and establishes spectroscopy of light muonic atoms and ions as a precise tool for studies of nuclear properties.

2.
Eur J Appl Physiol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138688

RESUMO

PURPOSE: To investigate the impact of voluntary hypoventilation at low lung volumes (VHL) during upper body repeated sprints (RS) on performance, metabolic markers and muscle oxygenation in Brazilian Jiu-Jitsu (BJJ) athletes. METHODS: Eighteen male well-trained athletes performed two randomized RS sessions, one with normal breathing (RSN) and another with VHL (RS-VHL), on an arm cycle ergometer, consisting of two sets of eight all-out 6-s sprints performed every 30 s. Peak (PPO), mean power output (MPO), and RS percentage decrement score were calculated. Arterial oxygen saturation (SpO2), heart rate (HR), gas exchange, and muscle oxygenation of the long head of the triceps brachii were continuously recorded. Blood lactate concentration ([La]) was measured at the end of each set. Bench press throw peak power (BPPP) was recorded before and after the RS protocol. RESULTS: Although SpO2 was not different between conditions, PPO and MPO were significantly lower in RS-VHL. V ˙ E, HR, [La], and RER were lower in RS-VHL, and VO2 was higher in RS-VLH than in RSN. Muscle oxygenation was not different between conditions nor was its pattern of change across the RS protocol influenced by condition. [La] was lower in RS-VHL than in RSN after both sets. CONCLUSION: Performance was significantly lower in RS-VHL, even though SPO2 was not consistent with hypoxemia. However, the fatigue index was not significantly affected by VHL, nor was the neuromuscular upper body power after the RS-VHL protocol. Additionally, [La] was lower, and oxygen consumption was higher in RS-VHL, suggesting a higher aerobic contribution in this condition.

4.
Microb Pathog ; 132: 282-292, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082527

RESUMO

Cutaneous fungal infections include onychomycosis, an infection of the nail that affects both healthy and immunocompromised patients. This study investigated the in vitro hydrolytic enzymes production, adhesion and biofilm formation capacity of Candida parapsilosis complex species and Kodamaea ohmeri isolates from onychomycoses of HIV/AIDS patients and also established the antifungal sensitivity profiles of these isolates. Onychomycosis in HIV/AIDS patients showed a high prevalence of emerging yeasts, among which C. parapsilosis complex species and K. ohmeri were the most frequent. Three C. parapsilosis sensu stricto and two C. orthopsilosis isolates were resistant to amphotericin B and 83% of isolates were resistant to terbinafine. All three different species evaluated were proteinase and hemolysin producers. All isolates adhered to stainless steel and siliconized latex surfaces, and carbohydrates intensified adhesion of all isolates. Isolates adhered to keratinous nail and 50% formed biofilms with strong intensity. In multispecies or polymicrobial biofilms, C. albicans and Staphylococcus aureus regulated the biofilm formation of the analyzed species, decreasing the number of their cells in biofilms. The isolation of emerging yeast species from onychomycosis which are great producers of hydrolytic enzymes and with high adhesion and biofilm formation capacity is a result that should be considered relevant in clinical practice. In addition, half of the isolates was resistant to at least one of the tested antifungals. Taken together these data corroborate the infectious capacity and viability of these isolates under favorable conditions.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Candida parapsilosis/isolamento & purificação , Onicomicose/microbiologia , Saccharomycetales/isolamento & purificação , Adulto , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida parapsilosis/efeitos dos fármacos , DNA Fúngico , Farmacorresistência Fúngica , Feminino , HIV , Humanos , Látex , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Onicomicose/epidemiologia , Saccharomycetales/efeitos dos fármacos , Aço Inoxidável , Terbinafina/farmacologia , Virulência , Adulto Jovem
5.
J Appl Toxicol ; 39(7): 1057-1065, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30883852

RESUMO

Occupational environments are major exposure routes to Cr(VI). However, Cr(VI) may also establish in bone tissues by ingestion or through Cr containing orthopaedic prostheses that, due to wear and corrosion, may release metal particles and ions potentially affecting bone tissue. The aim of this work was to evaluate the effects of clinically relevant concentrations of Cr(VI) in human osteoblasts, by integrating genotoxic effects, evaluated by the comet assay and cytokinesis-blocked micronucleus assay (scoring the presence of micronucleus, nucleoplasmic bridges and nuclear division index), with the effects on cell cycle and cell viability. Human osteoblasts MG-63 were in vitro exposed to Cr(VI) at concentrations ranging from 0.1 to 5 µm, for 24 and 48 hours. Results pointed out to a decrease of cell viability for both time exposures in a time- and dose-dependent manner, which was related to cell cycle arrest and DNA damage. Chromosome abnormalities were also observed. Hence, these data suggest that cells arrested in the cell division with DNA damage may have followed cell death pathways, while some surviving ones still revealed DNA damage at chromosome level indicating abnormal cell division progression. In conclusion, Cr(VI) induced cytotoxic and genotoxic effects in human bone cells at concentrations that could be found in patients with metal-on-metal prostheses. In addition, the early onset of genotoxic damage induced by Cr(VI) at low concentrations after 24 hours of cell exposure alert to the relevance of periodic monitoring of patients for genotoxicity diagnosis after implantation of prostheses before clinical symptoms appear.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cromo/toxicidade , Dano ao DNA , Poluentes Ambientais/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Osteoblastos/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Humanos , Testes para Micronúcleos , Osteoblastos/patologia
6.
J Sports Sci ; 37(17): 2037-2044, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31079555

RESUMO

Leucine metabolites may reduce training-induced inflammation; however, there is scant evidence for this assertion. We conducted a double-blind randomized controlled pragmatic trial where 40 male participants were allocated into 4 groups: α-hydroxyisocaproic acid group ([α-HICA], n = 10, Fat-free mass [FFM] = 62.0 ± 7.1 kg), ß-hydroxy-ß-methylbutyrate free acid group ([HMB-FA], n = 11, FFM = 62.7 ± 10.5 kg), calcium ß-hydroxy-ß-methylbutyrate group ([HMB-Ca], n = 9, FFM = 65.6 ± 10.1 kg) or placebo group ([PLA]; n = 10, FFM = 64.2 ± 5.7 kg). An 8-week whole-body resistance training routine (3 training sessions per week) was employed to induce gains in skeletal-muscle thickness. Skeletal muscle thickness (MT), one repetition maximum (1RM), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP) and tumour necrosis factor alpha (TNF-α) were assessed at baseline and at the end of weeks 4 and 8. Time-dependent increases were detected from baseline to week 8 for MT (vastus lateralis: p = 0.009; rectus femoris: p = 0.018), 1RM (back squat: α-HICA, 18.5% ± 18.9%; HMB-FA, 23.2% ± 16%; HMB-Ca, 10.5% ± 13.8%; PLA, 19.7% ± 9% and bench press: α-HICA, 13.8% ± 19.1%; HMB-FA, 15.5% ± 9.3%; HMB-Ca, 10% ± 10.4%; PLA, 14.4 ± 11.3%, both p < 0.001), IL-6, hsCRP (both p < 0.001) and TNF-α (p = 0.045). No differences were found between groups at any time point. No leucine metabolite attenuated inflammation during training. Additionally, backwards elimination regressions showed that no circulating inflammatory marker consistently shared variance with the change in any outcome. Using leucine metabolites to modulate inflammation cannot be recommended from the results obtained herein. Furthermore, increases in inflammatory markers, from training, do not correlate with any outcome variable and are likely the result of training adaptations.


Assuntos
Caproatos/administração & dosagem , Inflamação/sangue , Leucina/metabolismo , Treinamento Resistido , Fenômenos Fisiológicos da Nutrição Esportiva , Valeratos/administração & dosagem , Adulto , Biomarcadores/sangue , Composição Corporal , Proteína C-Reativa/análise , Cálcio , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Interleucina-6/sangue , Masculino , Força Muscular , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/fisiologia , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
7.
Molecules ; 24(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067626

RESUMO

The occurrence of damage on bacterial DNA (mediated by antibiotics, for example) is intimately associated with the activation of the SOS system. This pathway is related to the development of mutations that might result in the acquisition and spread of resistance and virulence factors. The inhibition of the SOS response has been highlighted as an emerging resource, in order to reduce the emergence of drug resistance and tolerance. Herein, we evaluated the ability of betulinic acid (BA), a plant-derived triterpenoid, to reduce the activation of the SOS response and its associated phenotypic alterations, induced by ciprofloxacin in Staphylococcus aureus. BA did not show antimicrobial activity against S. aureus (MIC > 5000 µg/mL), however, it (at 100 and 200 µg/mL) was able to reduce the expression of recA induced by ciprofloxacin. This effect was accompanied by an enhancement of the ciprofloxacin antimicrobial action and reduction of S. aureus cell volume (as seen by flow cytometry and fluorescence microscopy). BA could also increase the hyperpolarization of the S. aureus membrane, related to the ciprofloxacin action. Furthermore, BA inhibited the progress of tolerance and the mutagenesis induced by this drug. Taken together, these findings indicate that the betulinic acid is a promising lead molecule in the development helper drugs. These compounds may be able to reduce the S. aureus mutagenicity associated with antibiotic therapies.


Assuntos
Farmacorresistência Bacteriana/efeitos dos fármacos , Recombinases Rec A/genética , Staphylococcus aureus/genética , Triterpenos/farmacologia , Ciprofloxacina/efeitos adversos , Ciprofloxacina/farmacologia , DNA Bacteriano/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Mutagênese/efeitos dos fármacos , Mutagênese/genética , Triterpenos Pentacíclicos , Resposta SOS em Genética/efeitos dos fármacos , Resposta SOS em Genética/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Fatores de Virulência/genética , Ácido Betulínico
8.
J Toxicol Environ Health A ; 81(15): 705-717, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29913117

RESUMO

Cadmium (Cd) accumulation is known to occur predominantly in kidney and liver; however, low-level long-term exposure to Cd may also result in bone damage. Few studies have addressed Cd-induced toxicity in osteoblasts, particularly upon cell mitochondrial energy processing and putative associations with oxidative stress in bone. To assess the influence of Cd treatment on mitochondrial function and oxidative status in osteoblast cells, human MG-63 cells were treated with Cd (up to 65 µM) for 24 or 48 h. Intracellular reactive oxygen species (ROS), lipid and protein oxidation and antioxidant defense mechanisms such as total antioxidant activity (TAA) and gene expression of antioxidant enzymes were analyzed. In addition, Cd-induced effects on mitochondrial function were assessed by analyzing the activity of enzymes involved in mitochondrial respiration, membrane potential (ΔΨm), mitochondrial morphology and adenylate energy charge. Treatment with Cd increased oxidative stress, concomitantly with lipid and protein oxidation. Real-time polymerase chain reaction (qRT-PCR) analyses of antioxidant genes catalase (CAT), glutathione peroxidase 1 (GPX1), glutathione S-reductase (GSR), and superoxide dismutase (SOD1 and SOD2) exhibited a trend toward decrease in transcripts in Cd-stressed cells, particularly a downregulation of GSR. Longer treatment with Cd (48 h) resulted in energy charge states significantly below those commonly observed in living cells. Mitochondrial function was affected by ΔΨm reduction. Inhibition of mitochondrial respiratory chain enzymes and citrate synthase also occurred following Cd treatment. In conclusion, Cd induced mitochondrial dysfunction which appeared to be associated with oxidative stress in human osteoblasts.


Assuntos
Antioxidantes/metabolismo , Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Mitocôndrias/enzimologia , Mitocôndrias/fisiologia , Osteoblastos , Oxirredução , Proteínas/metabolismo
9.
Eur J Appl Physiol ; 118(3): 573-583, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29313111

RESUMO

PURPOSE: Long-term training influence on athletes' immune cell response to acute exercise has been poorly studied, despite the complexity of both chronic and acute adaptations induced by training. The purpose of the study is to study the influence of a 4-month swimming training cycle on the immune cell response to a high-intensity training session, during 24 h of recovery, considering sex, maturity, and age group. METHODS: Forty-three swimmers (16 females, 14.4 ± 1.1 years; 27 males, 16.2 ± 2.0) performed a standardized high-intensity session, after the main competition of the first (M1), and second (M2) macrocycles. Blood samples were collected before (Pre), immediately after (Post), 2 h after (Post2h) and 24 h after (Post24h) exercise. Haemogram and lymphocytes subsets were assessed by an automatic cell counter and by flow cytometry, respectively. Subjects were grouped according to sex, competitive age groups, or pubertal Tanner stages. Results express the percentage of relative differences from Pre to Post, Post2h and Post24h. Upper respiratory symptoms (URS) and training load were quantified. RESULTS: At M2, we observed smaller increases of leukocytes (M1: 14.0 ± 36.3/M2: 2.33 ± 23.0%) and neutrophils (M1: 57.1 ± 71.6/M2: 38.9 ± 49.9%) at Post; and less efficient recoveries of total lymphocytes (M1: - 22.0 ± 20.1/M2: - 30.0 ± 18.6%) and CD19+ (M1: 4.09 ± 31.1/M2: - 19.1 ± 24.4%) at Post2h. At Post2h, the increment of CD4+/CD8+ was smaller in youth (M1: 21.5 ± 16.0/M2: 9.23 ± 21.4%), and bigger in seniors (M1: 3.68 ± 9.21/M2: 23.2 ± 15.0%); and at Post24h late pubertal swimmers' CD16+56+ recovered less efficiently (M1: - 0.66 ± 34.6/M2: - 20.5 ± 34.2%). CONCLUSIONS: The training cycle induced an attenuated immune change immediately after exercise and a less efficient recovery of total lymphocytes, involving an accentuated CD19+ decrease. The concomitant higher URS frequency suggests a potential immune depression and a longer interval of susceptibility to infection.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Subpopulações de Linfócitos , Natação/fisiologia , Adolescente , Feminino , Humanos , Masculino
10.
Yale J Biol Med ; 91(2): 161-171, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29962922

RESUMO

Research involving dietary supplement interventions for sarcopenia and osteopenia in type 1 diabetes patients is scarce. Here we present a case study of a type 1 diabetic patient that was treated with supplemental alpha-hydroxy-isocaproic acid (α-HICA) for 120 days. Several measures of body composition by dual x-ray absorptiometry, blood markers, and maximum voluntary contraction parameters were assessed at baseline and after 120 days. The patient's baseline weight was 73.2 kg, which increased to 75.2 kg by the 120-day assessment. Salient mass distribution changes included increases of trunk fat mass (+0.4 kg), trunk fat free mass (+0.2 kg), total trunk mass (+0.2 kg), and a decrease of 8 percent in trunk fat mass contribution. Handgrip strength increased by 58.84 N, whereas isometric force in the leg press decreased by 347.15 N. Amelioration of BMD Z-scores from -0.7 to 0.5 and T-scores from -1.0 to -0.9 were noted. Importantly, full hematologic measures and weekly nutritional counselling assessments revealed no signs of adverse effects with α-HICA supplementation. Due to the imperative of maintaining FFM, strength and bone mass in these patients, additional research is necessary to confirm these promising results and to clarify whether leucine and/or one of its derivatives might be clinically useful.


Assuntos
Composição Corporal/efeitos dos fármacos , Caproatos/química , Caproatos/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Atrofia Muscular/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/metabolismo
11.
Medicina (Kaunas) ; 54(3)2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30344272

RESUMO

Background and objective: For a high level athlete, it is essential to ensure optimal energy as well as macro- and micro-nutrient and fluid intakes, in order to improve their performance during training and competition. Protein intake should be 1.2⁻2.1 g/kg/d, whereas the requirements for carbohydrate and fat intakes should be >5g/kg/d and 20⁻35% of energy, respectively. The micronutrient and fluid intakes in athletes were compared to the Dietary Reference Intake (DRI) and European Food Safety Authority (EFSA) recommendations, respectively. This study aimed to characterize and compare the nutritional habits of athletes at the preparatory and competitive phase, and to test if their nutritional intakes were in accordance with the recommendations. Materials and methods: A total of 276 professional athletes were assessed. To evaluate their nutritional intake, the athletes completed a 7 days food record. Under reporting was defined using a ratio of energy intake to basal metabolic rate (BMR) of 1.1. Body composition was assessed using dual energy X-ray absorptiometry (DXA). Results: Almost half (49%) of the athletes from the final sample reported lower measured intakes of carbohydrates and 27% reported a higher consumption of proteins than what was recommended. In both the preparatory and competitive phases, the micronutrients with a higher mismatch between the actual and recommended intakes were vitamins D and E, magnesium, folate, calcium, and zinc for both sexes, and iron intake for females. A large proportion of athletes reported a lower water intake. Compared to the recommendations, males reported a higher intake of carbohydrates, lipids, vitamins E, calcium, and magnesium (p <0.05) in the competitive phase, while females reported a lower ingestion of water, vitamins A and D, and calcium (p <0.05) in the preparatory phase. Conclusions: Overall, in the preparatory and competitive phases of the season, athletes reported a macro- and micro-nutrient intake below the recommendations, especially in the female athletic population. Dietary intakes in athletes need to be optimized and adjusted to their requirements, according to sex and sport, so as to avoid compromising health and performance.


Assuntos
Atletas/estatística & dados numéricos , Dieta/métodos , Ingestão de Energia , Estado Nutricional , Esportes/fisiologia , Adolescente , Composição Corporal , Inquéritos sobre Dietas , Feminino , Humanos , Masculino , Micronutrientes/análise , Fatores Sexuais , Adulto Jovem
12.
Water Sci Technol ; 76(5-6): 1081-1089, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28876249

RESUMO

Green roof technology has evolved in recent years as a potential solution to promote vegetation in urban areas. Green roof studies for Mediterranean climates, where extended drought periods in summer contrast with cold and rainy periods in winter, are still scarce. The present research study assesses the use of substrates with different compositions for the growth of six aromatic plant species - Lavandula dentata, Pelargonium odoratissimum, Helichrysum italicum, Satureja montana, Thymus caespititius and T. pseudolanuginosus, during a 2-year period, and the monitoring of water runoff quality. Growing substrates encompassed expanded clay and granulated cork, in combination with organic matter and crushed eggshell. These combinations were adequate for the establishment of all aromatic plants, allowing their propagation in the extensive system located on the 5th storey. The substrate composed of 70% expanded clay and 30% organic matter was the most suitable, and crushed eggshell incorporation improved the initial plant establishment. Water runoff quality parameters - turbidity, pH, conductivity, NH4+, NO3-, PO43- and chemical oxygen demand - showed that it could be reused for non-potable uses in buildings. The present study shows that selected aromatic plant species could be successfully used in green roofs in a Mediterranean climate.


Assuntos
Conservação dos Recursos Naturais , Habitação , Plantas/classificação , Qualidade da Água , Clima , Materiais de Construção , Região do Mediterrâneo , Chuva
13.
J Environ Sci (China) ; 53: 122-131, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28372736

RESUMO

In summer 2010, twenty eight (14 PM2.5 samples plus 14 samples PM2.5-10) smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse (PM2.5-10) and fine (PM2.5) smoke samples. The carbonaceous content (elemental and organic carbon) of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatography into three different classes of organic compounds (aliphatics, polycyclic aromatic hydrocarbons (PAHs) and carbonyl compounds). The organic speciation was performed by gas chromatography-mass spectrometry (GC-MS). Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon (OC/EC) ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic compounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Incêndios , Hidrocarbonetos/análise , Material Particulado/análise , Aerossóis/análise , Hidrocarbonetos Policíclicos Aromáticos , Portugal , Estações do Ano
14.
Nature ; 466(7303): 213-6, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20613837

RESUMO

The proton is the primary building block of the visible Universe, but many of its properties-such as its charge radius and its anomalous magnetic moment-are not well understood. The root-mean-square charge radius, r(p), has been determined with an accuracy of 2 per cent (at best) by electron-proton scattering experiments. The present most accurate value of r(p) (with an uncertainty of 1 per cent) is given by the CODATA compilation of physical constants. This value is based mainly on precision spectroscopy of atomic hydrogen and calculations of bound-state quantum electrodynamics (QED; refs 8, 9). The accuracy of r(p) as deduced from electron-proton scattering limits the testing of bound-state QED in atomic hydrogen as well as the determination of the Rydberg constant (currently the most accurately measured fundamental physical constant). An attractive means to improve the accuracy in the measurement of r(p) is provided by muonic hydrogen (a proton orbited by a negative muon); its much smaller Bohr radius compared to ordinary atomic hydrogen causes enhancement of effects related to the finite size of the proton. In particular, the Lamb shift (the energy difference between the 2S(1/2) and 2P(1/2) states) is affected by as much as 2 per cent. Here we use pulsed laser spectroscopy to measure a muonic Lamb shift of 49,881.88(76) GHz. On the basis of present calculations of fine and hyperfine splittings and QED terms, we find r(p) = 0.84184(67) fm, which differs by 5.0 standard deviations from the CODATA value of 0.8768(69) fm. Our result implies that either the Rydberg constant has to be shifted by -110 kHz/c (4.9 standard deviations), or the calculations of the QED effects in atomic hydrogen or muonic hydrogen atoms are insufficient.

15.
Water Sci Technol ; 73(8): 1842-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27120638

RESUMO

Green roofs (GRs) are becoming a trend in urban areas, favouring thermal performance of buildings, promoting removal of atmospheric pollutants, and acting as possible water collection spots. Rainwater harvesting systems in buildings can also contribute to the management of stormwater runoff reducing flood peaks. These technologies should be enhanced in Mediterranean countries where water scarcity is increasing and the occurrence of extreme events is becoming very significant, as a result of climate change. An extensive pilot GR with three aromatic plant species, Satureja montana, Thymus caespititius and Thymus pseudolanuginosus, designed to study several parameters affecting rainwater runoff, has been in operation for 12 months. Physico-chemical analyses of roof water runoff (turbidity, pH, conductivity, NH4(+), NO3(-), PO4(3-), chemical oxygen demand) have shown that water was of sufficient quality for non-potable uses in buildings, such as toilet flushing. An innovative approach allowed for the development of an expression to predict a 'monthly runoff coefficient' of the GR system. This parameter is essential when planning and designing GRs combined with rainwater harvesting systems in a Mediterranean climate. This study is a contribution to improving the basis for the design of rainwater harvesting systems in buildings with extensive GRs under a Mediterranean climate.


Assuntos
Clima , Conservação dos Recursos Naturais/métodos , Materiais de Construção , Chuva , Arquitetura de Instituições de Saúde , Região do Mediterrâneo , Poluentes Químicos da Água , Qualidade da Água
16.
J Sports Sci Med ; 13(3): 708-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25177203

RESUMO

Studies examining the immune response to acute intensive swimming have shown increased leukocytosis and lymphocyte populations. However, studies concerning mucosal immunity and sex differences remain controversial. The objective of the study was to examine sex differences on the immune response to maximal incremental swimming exercise in well trained swimmers. Participants (11 females, controlled for menstrual cycle phase effects; 10 males) performed a maximal incremental 7x200 m front crawl set. Fingertip capillary blood samples were obtained after each 200 m swim for lactate assessment. Venous blood and saliva samples were collected before and 5 minutes after the swimming test to determine total numbers of leukocytes, lymphocytes and subpopulations, and serum and salivary immunoglobulin A (IgA) levels. IgA secretion rate was calculated. Menstrual cycle phase did not influence the immune response to exercise. As for sex differences, exercise induced an increase in leukocytes, total lymphocytes, CD3(+), CD4(+), CD8(+), and CD16(+)/56(+) in males. In females, only leukocytosis, of a lower magnitude than was observed in males, occurred. CD19(+) increased and CD4(+)/CD8(+) ratio decreased in both groups following exercise whilst IgA, SIgA concentrations, and srIgA did not change. Both males and females finished the incremental exercise very close to the targeted race velocity, attaining peak blood lactate concentrations of 14.6±2.25 and 10.4±1.99 mmol.L(-1), respectively. The effect of a maximal incremental swimming task on immunity is sex dependent and more noticeable in men. Males, as a consequence of higher levels of immunosurveillance may therefore be at a lower risk of infection than females. Key PointsMaximal exercise induces an immune response.This study investigated the influence of sex over the leukocytes subpopulations and mucosal immune responses to maximal swimming.Male swimmers showed a stronger increase of T helper, T cytotoxic and NK lymphocytes than females, suggesting they may be at a lower risk of infection, due to a higher immunosurveillance.Mucosal immunity remained unchanged in both sexes.

17.
Pharmacol Res Perspect ; 12(5): e1235, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39291726

RESUMO

Cardiovascular diseases are the leading cause of death globally, making the use of oral anticoagulants for prevention increasingly important. Historically, warfarin has played a significant role in this context. In recent years, introduction of new oral anticoagulants, such as rivaroxaban, apixaban, dabigatran, and edoxaban, has been seen. This study evaluates the risk associated with the use of oral anticoagulants by analyzing spontaneous adverse drug reactions reported to the Portuguese Pharmacovigilance System from 2012 to 2021. The study includes 951 adverse drug reactions reports, with the majority (n = 770; 80.97%) classified as serious. Of the 770 serious adverse drug reactions reports, the most commonly reported seriousness criterion was "Clinically Important" (n = 350; 45.45%). In terms of demographics, there was a higher reporting rate among the elderly population, with a greater prevalence of females. The System Organ Class group with the highest number of adverse drug reactions was "Gastrointestinal disorders," with the most commonly reported Preferred Term being "Gastrointestinal hemorrhage," and dabigatran was the most frequently reported drug. In summary, oral anticoagulants have adverse drug reactions that require continuous monitoring. Accurate identification and monitorization of adverse drug reactions is an important starting point to improve drug safety in population.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Anticoagulantes , Farmacovigilância , Humanos , Anticoagulantes/efeitos adversos , Anticoagulantes/administração & dosagem , Idoso , Feminino , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Masculino , Administração Oral , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Portugal/epidemiologia , Adulto , Adolescente , Adulto Jovem , Criança , Pré-Escolar , Lactente , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Recém-Nascido
18.
J Clin Med ; 13(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38337477

RESUMO

Postmenopausal abnormal uterine bleeding is a common clinical problem addressed in gynaecological practice and should prompt clinical investigation due to the significant prevalence of malignant and premalignant lesions of the endometrium in this age group. Nevertheless, other causes should be considered, since its diagnostic and therapeutic management may differ considerably. Here, we present a case of a colouterine fistula due to chronic diverticulitis presenting with postmenopausal abnormal uterine bleeding. This is an infrequent occurrence and is caused by the rupture of a diverticular abscess into the uterine wall, resulting in an inflammatory adhesion of the colon and uterus, with necrosis and subsequent fistula formation. The clinical presentation is variable and may include abdominal pain, gastrointestinal tract symptoms, vaginal discharge, and abnormal uterine bleeding. The laboratory and imaging techniques may be not completely conclusive and definitive diagnosis can be made intraoperatively. There are different treatment options, with en bloc resection and primary anastomosis being used most often, allowing complete treatment. The prognosis for a colouterine fistula secondary to diverticulitis is excellent after surgery. This case highlights the importance of clinical suspicion of an unusual cause of uterine bleeding and an effective and multidisciplinary approach that allowed complete surgical treatment and patient recovery.

19.
Int J Biol Macromol ; 271(Pt 1): 132577, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795887

RESUMO

Staphylococcus aureus is a pathogen widely involved in wound infection due to its ability to release several virulence factors that impair the skin healing process, as well as its mechanism of drug resistance. Herein, sodium alginate and chitosan were combined to produce a hydrogel for topical delivery of neomycin to combat S. aureus associated with skin complications. The hydrogel was formulated by combining sodium alginate (50 mg/mL) and chitosan (50 mg/mL) solutions in a ratio of 9:1 (HBase). Neomycin was added to HBase to achieve a concentration of 0.4 mg/mL (HNeo). The incorporation of neomycin into the product was confirmed by scanning electron microscopy, FTIR and TGA analysis. The hydrogels produced are homogeneous, have a high swelling capacity, and show biocompatibility using erythrocytes and fibroblasts as models. The formulations showed physicochemical and pharmacological stability for 60 days at 4 ± 2 °C. HNeo totally inhibited the growth of S. aureus after 4 h. The antimicrobial effects were confirmed using ex vivo (porcine skin) and in vivo (murine) wound infection models. Furthermore, the HNeo-treated mice showed lower severity scores than those treated with HBase. Taken together, the obtained results present a new low-cost bioproduct with promising applications in treating infected wounds.


Assuntos
Alginatos , Antibacterianos , Quitosana , Hidrogéis , Neomicina , Staphylococcus aureus , Quitosana/química , Quitosana/farmacologia , Alginatos/química , Alginatos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Camundongos , Neomicina/farmacologia , Neomicina/química , Neomicina/administração & dosagem , Antibacterianos/farmacologia , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/microbiologia , Infecções Cutâneas Estafilocócicas/patologia , Portadores de Fármacos/química , Pele/efeitos dos fármacos , Pele/microbiologia
20.
Biomed Pharmacother ; 173: 116389, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461682

RESUMO

Staphylococcus aureus is one of the most common bacterial isolates found in wounds. Thus, innovative dressings, such as hydrogels, are interesting vehicles for incorporating bioactive compounds like those from Melaleuca alternifolia essential oil (MaEO). In this study, we evaluated the antimicrobial and anti-inflammatory potential of MaEO incorporated into an alginate and chitosan hydrogel for treating wounds infected by S. aureus. The hydrogel incorporated with MaEO 1% (HMa 1%) was homogeneous with a bright pale-yellow color and the characteristic smell of Melaleuca. The incorporation of MaEO 1% does not affect the stability of the hydrogel, which was stable up to 90 days of storage. The Scanning electron microscopy analysis revealed that hydrogels showed irregular surfaces and interconnected porous structures with accumulations of oil crystals distributed throughout the formulation. HMa 1% has a high moisture content (95.1%) and can absorb simulated wound fluid. Regarding the antimicrobial effects, HMa 1% reduced the growth of S. aureus ATCC 6538 in both in vitro conditions and in an ex vivo model of wounds using porcine skin. In addition, the dairy topical treatment of murine skin lesions with HMa 1% induced a significant reduction of the wound area, inflammation score, and bacterial load, as well as tissue re-epithelialization and modulation of inflammatory mediators. Therefore, hydrogel incorporated with MaEO 1% has excellent potential to be used in the pharmacotherapy of infected wounds.


Assuntos
Anti-Infecciosos , Melaleuca , Óleos Voláteis , Infecções Estafilocócicas , Óleo de Melaleuca , Suínos , Animais , Camundongos , Staphylococcus aureus , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Óleos Voláteis/química , Melaleuca/química , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Anti-Infecciosos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Óleo de Melaleuca/farmacologia , Óleo de Melaleuca/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
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