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The light reflected by the dorsal side of butterfly wings often functions as a signal for, e.g., mate choice, thermoregulation, and/or predator deterrence, while the ventral wing reflections are generally used for crypsis and camouflage. Here, we propose that transmitted light can also have an important role in visual signaling because, in many butterfly species, the dorsal and ventral wing sides are similarly patterned and locally more or less translucent. Extreme examples are the Japanese yellow swallowtail (Papilio xuthus Linnaeus, 1758) and the Yellow glassy tiger (Parantica aspasia Fabricius, 1787). Their wings exhibit a similar color pattern in reflected and transmitted light, which allows enhanced visual signaling, especially in flight. Contrasting cases in which the coloration and patterning of dorsal and ventral wings strongly differ are the papilionid Papilio nireus Linnaeus, 1758, and the pierid Delias nigrina Fabricius, 1775. The wings observed in reflected or transmitted light then show very different color patterns. Wing translucence thus will strongly affect a butterfly's visual signal.
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BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease with a multifactorial genesis including genetic predispositions and environmental risk and trigger factors. One of the latter possibly is smoking, indicated by an increased prevalence of AD in adults and children that are actively or passively exposed to cigarette smoke. OBJECTIVES: In this study, AD characteristics and its atopic comorbidities are compared in smoking and non-smoking AD patients. METHODS: TREATgermany is a non-interventional clinical registry which includes patients with moderate to severe AD in Germany. Baseline data of patients included in TREATgermany from inception in June 2016 to April 2020 in 39 sites across Germany was analysed comparing AD disease characteristics and comorbidities in smokers vs. non-smokers. RESULTS: Of 921 patients, 908 (male: 58.7%) with a mean age of 41.9 ± 14.4 reported their smoking status. The objective Scoring of Atopic Dermatitis (oSCORAD) did not differ between smokers (n = 352; 38.8%) and non-smokers, however, lesions' intensity of oozing/crusts and excoriations as well as patient global assessment scores (PGA) of AD severity were higher in smoking as opposed to non-smoking patients. Smokers reported a lower number of weeks with well-controlled AD and more severe pruritus than non-smokers. Total IgE levels were more elevated in smokers and they displayed a younger age at the initial diagnosis of bronchial asthma. After adjustment for potential confounders, the increased intensity of oozing/crusts, the reduced number of weeks with well-controlled AD and the greater pruritus remained different in smokers compared to non-smokers. In addition, smoking patients with adult-onset AD showed a 2.5 times higher chance of involvement of the feet. CONCLUSIONS: German registry data indicate that AD patients who smoke have a higher disease burden with a different distribution pattern of lesions in adult-onset AD.
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Dermatite Atópica , Eczema , Adulto , Criança , Dermatite Atópica/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prurido , Sistema de Registros , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Outdoor workers are occupationally exposed to significantly higher ultraviolet (UV) doses than the rest of the population. Recent data show a doubling of basal cell carcinoma (BCC) risk in outdoor workers with high occupational UV exposure. OBJECTIVES: To examine the stability and robustness of BCC risk estimators. METHODS: Sensitivity analyses to test model assumptions considering socioeconomic status, influence of matching procedure, gender and latency, regional differences (east/west), urban/rural cases/controls, and dual diagnoses (squamous cell carcinoma [SCC]/actinic keratoses grade III [AKIII]/Bowen disease [BD] and BCC) were performed. RESULTS: BCC risk was consistently higher for high occupationally UV-exposed individuals than for intermediate UV-exposed individuals, regardless of matching procedure, latency, regional differences (east/west), urban/rural recruitment of cases/controls, and dual diagnoses (SCC/AKIII/BD and BCC), sex, and socioeconomic status. CONCLUSION: The risk estimator for the association between exposure to solar UV radiation at work and the risk of developing BCC showed a high degree of stability and robustness for all variables investigated. The analyses support the recently published findings on the doubling of BCC risk in outdoor workers with high occupational UV exposure.
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Carcinoma Basocelular , Ceratose Actínica , Doenças Profissionais , Exposição Ocupacional , Neoplasias Cutâneas , Carcinoma Basocelular/diagnóstico , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/etiologia , Humanos , Exposição Ocupacional/efeitos adversos , Fatores de Risco , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Raios Ultravioleta/efeitos adversosRESUMO
BACKGROUND: A two-fold risk increase to develop basal cell carcinoma was seen in outdoor workers exposed to high solar UV radiation compared to controls. However, there is an ongoing discussion whether histopathological subtype, tumor localization and Fitzpatrick phototype may influence the risk estimates. OBJECTIVES: To evaluate the influence of histological subtype, tumor localization and Fitzpatrick phototype on the risk to develop basal cell carcinoma in highly UV-exposed cases and controls compared to those with moderate or low solar UV exposure. METHODS: Six hundred forty-three participants suffering from incident basal cell carcinoma in commonly sun-exposed anatomic sites (capillitium, face, lip, neck, dorsum of the hands, forearms outside, décolleté) of a population-based, case-control, multicenter study performed from 2013 to 2015 in Germany were matched to controls without skin cancer. Multivariate logistic regression analysis was conducted stratified for histological subtype, phototype 1/2 and 3/4. Dose-response curves adjusted for age, age2, sex, phototype and non-occupational UV exposure were calculated. RESULTS: Participants with high versus no (OR 2.08; 95% CI 1.24-3.50; p = 0.006) or versus moderate (OR 2.05; 95% CI 1.15-3.65; p = 0.015) occupational UV exposure showed a more than two-fold significantly increased risk to develop BCC in commonly UV-exposed body sites. Multivariate regression analysis did not show an influence of phototype or histological subtype on risk estimates. The restriction of the analysis to BCC cases in commonly sun-exposed body sites did not influence the risk estimates. The occupational UV dosage leading to a 2-fold increased basal cell carcinoma risk was 6126 standard erythema doses. CONCLUSION: The risk to develop basal cell carcinoma in highly occupationally UV-exposed skin was doubled consistently, independent of histological subtype, tumor localization and Fitzpatrick phototype.
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BACKGROUND: The Atopic Dermatitis (AD) TREATgermany registry was initiated by the German Society for Dermatology (DDG) in 2011 to evaluate the 'real-life' situation of health care for patients with AD. OBJECTIVES: Interim data analysis on baseline characteristics as well as current and prescribed systemic treatments of the TREATgermany registry patients. METHODS: Patients (≥18 years) with moderate-to-severe AD [objective (o)SCORAD > 20], or with current or previous anti-inflammatory systemic treatment for AD within 24 months, were included and are followed up over at least 24 months. To assess clinical signs, the eczema area severity index (EASI, 0-72), the oSCORAD (0-83) and the Investigator Global Assessment (IGA; 6-point scale) were used. The disease severity was globally scored by the patients [Patient Global Assessment (PGA); six-step Likert scale]. Disease symptoms were assessed by the patient-oriented eczema measure (POEM, 0-28) and numeric rating scales (NRS, 0-10). Health-related quality of life was measured using the dermatological life quality index (DLQI, 0-30). RESULTS: A total of 612 patients were recruited across 32 sites between 06/2016 and 01/2019 (mean age: 42.6 ± 14.2 years; mean oSCORAD: 40.8 ± 16.3). The mean POEM score was 16.3 ± 7.5. Pruritus was rated highest among subjective symptoms (NRS: 5.4 ± 2.7). The mean DLQI value was 11.3 ± 7.5. The frequency of arterial hypertension was lower (20.8%) compared with the general population, whilst this was higher for depression (10%). More than 60% of the patients had received systemic glucocorticosteroids, and 36.8% had received cyclosporine A prior to inclusion. Dupilumab was the leading substance documented as either 'current' (12.1%) or 'prescribed' (31.4%) at baseline. CONCLUSIONS: These 'real-life' data clearly demonstrate the substantial disease burden. Most of TREATgermany patients were already treated with or prescribed dupilumab at baseline. Moreover, current findings indicate the urgent need for further alternative agents in order to achieve a perceptible improvement of quality of life of patients with moderate-to-severe AD.
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Dermatite Atópica , Eczema , Adulto , Dermatite Atópica/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Qualidade de Vida , Sistema de Registros , Índice de Gravidade de DoençaRESUMO
Obesity and type 2 diabetes lead to dramatically increased risks of atherosclerosis and CHD. Multiple mechanisms converge to promote atherosclerosis by increasing endothelial oxidative stress and up-regulating expression of pro-inflammatory molecules. Microvesicles (MV) are small ( < 1 µm) circulating particles that transport proteins and genetic material, through which they are able to mediate cell-cell communication and influence gene expression. Since MV are increased in plasma of obese, insulin-resistant and diabetic individuals, who often exhibit chronic vascular inflammation, and long-term feeding of a high-fat diet (HFD) to rats is a well-described model of obesity and insulin resistance, we hypothesised that this may be a useful model to study the impact of MV on endothelial inflammation. The number and cellular origin of MV from HFD-fed obese rats were characterised by flow cytometry. Total MV were significantly increased after feeding HFD compared to feeding chow (P< 0·001), with significantly elevated numbers of MV derived from leucocyte, endothelial and platelet compartments (P< 0·01 for each cell type). MV were isolated from plasma and their ability to induce reactive oxygen species (ROS) formation and vascular cell adhesion molecule (VCAM)-1 expression was measured in primary rat cardiac endothelial cells in vitro. MV from HFD-fed rats induced significant ROS (P< 0·001) and VCAM-1 expression (P= 0·0275), indicative of a pro-inflammatory MV phenotype in this model of obesity. These findings confirm that this is a useful model to further study the mechanisms by which diet can influence MV release and subsequent effects on cardio-metabolic health.
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Micropartículas Derivadas de Células/metabolismo , Dieta Hiperlipídica/efeitos adversos , Gorduras na Dieta/efeitos adversos , Células Endoteliais/efeitos dos fármacos , Animais , Gorduras na Dieta/administração & dosagem , Células Endoteliais/metabolismo , Inflamação/patologia , Resistência à Insulina , Masculino , Miocárdio/citologia , Miocárdio/metabolismo , Obesidade/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Tyrosine kinase inhibitors (TKI) have changed the natural course of chronic myeloid leukemia (CML). With the advent of second-generation TKI safety and efficacy issues have gained interest. The randomized CMLâ-âStudy IV was used for a long-term evaluation of imatinib (IM). 1503 patients have received IM, 1379 IM monotherapy. After a median observation of 7.1 years, 965 patients (64%) still received IM. At 10 years, progression-free survival was 82%, overall survival 84%, 59% achieved MR(5), 72% MR(4.5), 81% MR(4), 89% major molecular remission and 92% MR(2) (molecular equivalent to complete cytogenetic remission). All response levels were reached faster with IM800 mg except MR(5). Eight-year probabilities of adverse drug reactions (ADR) were 76%, of grades 3-4 22%, of non-hematologic 73%, and of hematologic 28%. More ADR were observed with IM800 mg and IM400 mg plus interferon α (IFN). Most patients had their first ADR early with decreasing frequency later on. No new late toxicity was observed. ADR to IM are frequent, but mostly mild and manageable, also with IM 800 mg and IM 400 mg+IFN. The deep molecular response rates indicate that most patients are candidates for IM discontinuation. After 10 years, IM continues to be an excellent initial choice for most patients with CML.
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Antineoplásicos/administração & dosagem , Benzamidas/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Idoso , Antineoplásicos/efeitos adversos , Benzamidas/efeitos adversos , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Mesilato de Imatinib , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Piperazinas/efeitos adversos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Indução de Remissão , Resultado do TratamentoRESUMO
Positron emission tomography/computer tomography (PET/CT) is an established method in preclinical research in small animal disease models and the clinical diagnosis of cancer. It combines functional information of the positron-emitting biomarker with the anatomical data obtained from the CT image. Thus, it allows for 4D in vivo investigation of biological processes. Recently, PET/CT was used to monitor bone growth of chicken embryos using (18)F-fluoride as a bone-seeking tracer. We are interested in investigating the adequacy of additional PET/CT tracers in chicken embryos as an in vivo model system. For this reason, we evaluated several positron emitting compounds typically used in clinical tests or if these were not commercially available, we synthesised them. We studied the properties of these (18)F- and (68)Ga-labelled tracers and of (64)Cu-chloride in catheterised eggs via small animal microPET/CT. 2-Deoxy-2-[(18)F]fluoroglucose ([(18)F]FDG) was primarily absorbed at the sites of bone growth. (64)Cu chloride and a (68)Ga-labelled amyloid-fibril-binding antibody accumulated in the liver, while the (68)Ga-albumin desferrioxamine conjugate signal in liver decreased over time. These results indicate that these biomarkers can potentially be used for the monitoring of biological processes in chicken eggs as an animal model.
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Embrião de Galinha/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Animais , Fatores de Tempo , Tomografia Computadorizada por Raios XRESUMO
Meningitis in adults due to infection with Mycoplasma hominis is rarely reported. Here, we document the third case of M. hominis meningitis in an adult individual, developed upon neurosurgery following a subarachnoid haemorrhage. Our findings are noteworthy, because the presence of M. hominis in cerebrospinal fluid cannot be identified by standard culturing, Gram-staining, or matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Importantly, however, 16S rDNA sequencing did lead to an unambiguous diagnosis and guided successful antimicrobial therapy. Based on our present findings and a review of the respective literature, we conclude that M. hominis should be considered as a candidate causative agent of infections of the central nervous system following neurosurgical procedures, especially if there is no response to standard antimicrobial therapy, and routine culturing yields negative results.
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Meningites Bacterianas/diagnóstico , Meningites Bacterianas/tratamento farmacológico , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/tratamento farmacológico , Mycoplasma hominis/isolamento & purificação , Adolescente , Adulto , Técnicas Bacteriológicas/métodos , Líquido Cefalorraquidiano/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Meningites Bacterianas/microbiologia , Pessoa de Meia-Idade , Infecções por Mycoplasma/microbiologia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Adulto JovemRESUMO
For over 25 years zero kinetic energy (ZEKE) spectroscopy has yielded a rich foundation of high-resolution results of molecular ions. This was based on the discovery in the late 60's of long-lived ion states throughout the ionization continuum of molecular ions. Here, an example is chosen from another fundamental system pioneered at this university. The mass-analyzed threshold ionization (MATI) spectra of jet-cooled chromium bisarene complexes (η(6)-RPh)(2)Cr (R = Me (1), Et (2), i-Pr (3), and t-Bu (4)) have been measured and interpreted on the basis of DFT calculations. The MATI spectra of complexes 1 and 2 appear to reveal features arising from ionizations of the isomers formed by the rotation of one arene ring relative to the other. The 1 and 2 MATI spectra show two intense peaks corresponding to the 0(0)(0) ionizations with inverse intensity ratios. As indicated by the DFT calculations, the intensity ratio change on going from 1 to 2 results from different isomers contributing to each MATI peak. The ionization energies corresponding to the 0(0)(0) peaks are 42746 ± 5 and 42809 ± 5 cm(-1) for compound 1 and 42379 ± 5 and 42463 ± 5 cm(-1) for complex 2. The 1 and 2 spectra show also the weaker features representing transitions to the vibrationally excited cationic levels, the signals of individual rotamers being detected and assigned on the basis of calculated vibrational frequencies. The MATI spectra of compounds 3 and 4 reveal only one strong peak because of close ionization potentials of the isomers contributing to the MATI signal. The 3 and 4 ionization energies are 42104 ± 5 and 41917 ± 5 cm(-1), respectively. The precise values of ionization energies obtained from the MATI spectra reveal a nonlinear dependence of the IE on the number of Me groups in the alkyl substituents of (η(6)-RPh)(2)Cr. This can be explained by an increase in the molecular zero point energies on methylation of the substituents.
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Derivados de Benzeno/química , Cromo/química , Compostos Organometálicos/química , Simulação de Dinâmica Molecular , Compostos Organometálicos/síntese química , Espectroscopia Fotoeletrônica , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Leucocyte transendothelial migration is strictly regulated to prevent undesired inflammation and collateral damage of endothelial cells by activated neutrophils/monocytes. We hypothesized that in anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAV) patients' dysregulation of this process might underlie vascular inflammation. Peripheral blood mononuclear cells (PBMC) and neutrophils from AAV patients (n = 12) and healthy controls (HC, n = 12) were isolated. The influence of human umbilical vein endothelial cells (HUVEC) on neutrophil/monocytes function was tested by N-formyl-methionyl-leucyl-phenyl-alanine (fMLP)- and phorbol 12-myristate 13-acetate (PMA)-mediated ROS production, degranulation and interleukin (IL)-8 production. In addition, the ability of lipopolysaccharide (LPS)-stimulated PBMC to produce tumour necrosis factor (TNF)-alpha in the presence or absence of HUVEC was tested. HUVEC inhibited ROS production dose-dependently by fMLP-stimulated neutrophils but did not influence degranulation. No differences between neutrophils from HC and AAV were found. However, in only one active patient was degranulation inhibited significantly by HUVEC only before cyclophosphamide treatment, but not 6 weeks later. Co-cultures of HUVEC with LPS-stimulated neutrophils/monocytes increased IL-8 production while TNF-alpha production was inhibited significantly. There was no apparent difference between AAV patients and HC in this respect. Our findings demonstrate that HUVEC are able to inhibit ROS and modulate cytokine production upon stimulation of neutrophils or monocytes. Our data do not support the hypothesis that endothelial cells inhibit ROS production of neutrophils from AAV patients inadequately. Impaired neutrophil degranulation may exist in active patients, but this finding needs to be confirmed.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/metabolismo , Células Endoteliais/metabolismo , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adenosina Desaminase/farmacologia , Adenosina-5'-(N-etilcarboxamida)/farmacologia , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/imunologia , Degranulação Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Humanos , Interleucina-8/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Peroxidase/metabolismo , Explosão Respiratória/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Hydrogen bonds are essential tie points inside protein structures. They undergo dynamic rupture and rebonding processes on the time scale of tens of picoseconds. Proteins can partially rearrange during such ruptures. In previous work, we performed molecular dynamics simulations of these fluctuating hydrogen bonds. This indicated long-range entropy and energy contributions extending far into the liquid environment. The results showed that the binding of a given hydrogen bond is much reduced as a result of these interactions in water, as is required for biological activity and in very good confirmation of known experimental results. The larger water environment directly interacts with the hydrogen bond essentially due to long-range molecular interactions. Such a substantial lowering of the energy of the hydrogen bond in water brings it into the range of activation by many biological processes ( Sheu et al. Chem. Phys. Lett. 2008 , 462 , 1 - 5 ). Thus, the water medium profoundly increases the rate. Furthermore, very large entropic changes are associated with the rupture of hydrogen bonds in water, whereas no such effects are seen for the isolated molecule. Interestingly, such an increase in rates in water is still accompanied by a large negative change in entropy in the extended solvent environment, and this reduces the rate by some 2 orders of magnitude. Recent molecular dynamics experiments in D(2)O substantiate this model and show a large solvent isotope effect. In this work, we used lipids as the environment for the hydrogen bond and discovered that the energy is also reduced from that found in the isolated molecule, but not as far as in water. On the other hand, we found that no entropy penalty exists for breaking the hydrogen bond in lipids, as seen for water. These two effects compensate, even though the energy is some 2 times larger. The entropic penalty is reduced such that the rate is higher than in water despite the higher energy. This is a significant result for understanding the reactivity and dynamics of proteins in lipids. It should be noted that these are very important solvent effects on entropies and free energies that are not usually reflected in statistical thermodynamic computations for reactants and products. The very long-range effect of the solvent makes substantial contributions to kinetic rate constants and is readily evaluated in this kinetic method. To ignore these long-range environmental effects on the entropy can lead to very spurious results when calculating rates of protein mobilities. Hence, the results not only agree very well with the known hydrogen-bond energies directly as a result of various environmental factors, but even correctly predict a phase transition in the lipid.
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Proteínas de Membrana/química , Ligação de Hidrogênio , Cinética , Modelos Químicos , Modelos Moleculares , Temperatura , Termodinâmica , Fatores de Tempo , Água/químicaRESUMO
The aim of the study was to report the relationship between cadence and power developed by professional cyclists during high mountain ascents of the Tour de France. From the 10 cyclists (30 +/- 4 years, 178 +/- 8 cm, 69 +/- 6 kg) involved in the study, 108 ascents were recorded and analyzed using a mobile power measurement device (SRM Training Systems, Jülich, Germany). Based on topographic characteristics, the ascents were categorized into 1st and Hors Category (HC) climbs. During the ascents of the 1st Category climbs, power output averaged 312 +/- 43 W (4.5 +/- 0.6 W/kg) with a mean cadence of 73 +/- 6 rpm and a mean duration of 37 : 41 +/- 16 : 16 min. Power output averaged 294 +/- 36 W (4.3 +/- 0.6 W/kg) at a mean cadence of 70 +/- 6 rpm during 57 : 40 +/- 10 : 32 min on HC climbs. The maximal mean power for long durations (1800 s) showed a mean power output of 327 W and 346 W for the 1st and HC climbs, respectively. The evaluation of the cadence-power output and the distance per pedaling cycle-power output relationship shows that high power outputs are mainly yielded by higher pedaling cadences and higher gears.
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Ciclismo/fisiologia , Músculo Esquelético/fisiologia , Resistência Física/fisiologia , Adulto , Desempenho Atlético/fisiologia , HumanosRESUMO
The aim of this study was to evaluate the demands of riding a "Grand Tour" by monitoring both heart rate and power output in 15 professional cyclists. SRM power output profiles (SRM Trainingsystem, Jülich, Germany) were collected during 148 mass start stages during the 2005 Tour de France and analyzed to establish average power, heart rate (HR) and cadence produced in different terrain categories (flat [FLT]; semi-mountainous [SMT]; mountainous [MT]). The maximal mean power (MMP) for progressively longer durations was quantified. Average HR was similar between FLT (133 +/- 10 bpm) and SMT (134 +/- 8 bpm) but higher during MT (140 +/- 3 bpm). Average power output revealed a similar trend (FLT 218 +/- 21 W [3.1 +/- 0.3 W/kg], SMT 228 +/- 22 W [3.3 +/- 0.3 W/kg], and MT 234 +/- 13 W [3.3 +/- 0.2 W/kg]). Cadence during MT was approximately 6 - 7 rpm lower (81 +/- 15 rpm) compared to FLT or SMT. During MT stages, the MMP for 1800 sec. was highest (394 W vs. 342 W) but the MMP 15 was lower (836 W vs. 895 W) compared to FLT. The data document comprehensively the power output demands during the Tour de France.
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Limiar Anaeróbio/fisiologia , Ciclismo/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Adulto , Comportamento Competitivo , França , Frequência Cardíaca/fisiologia , Humanos , Masculino , Esforço Físico , Estudos Prospectivos , TempoRESUMO
Biological systems often transport charges and reactive processes over substantial distances. Traditional models of chemical kinetics generally do not describe such extreme distal processes. In this Review, an atomistic model for a distal transport of information, which was specifically developed for peptides, is considered. Chemical reactivity is taken as the result of distal effects based on two-step bifunctional kinetics involving unique, very rapid motional properties of peptides in the subpicosecond regime. The bifunctional model suggests highly efficient transport of charge and reactivity in an isolated peptide over a substantial distance; conversely, a very low efficiency in a water environment was found. The model suggests ultrafast transport of charge and reactivity over substantial molecular distances in a peptide environment. Many such domains can be active in a protein.
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Algoritmos , Íons/química , Peptídeos/química , Proteínas/química , Aminoácidos/química , Aminoácidos/metabolismo , Transporte Biológico , Membrana Celular/química , Membrana Celular/metabolismo , Cinética , Espectrometria de Massas , Potenciais da Membrana , Modelos Moleculares , Peptídeos/metabolismo , Proteínas/metabolismoRESUMO
In the last years, the interest in sport nutrition has increased. The purpose of this study was to quantify the nutritional status of eleven cyclists of a professional team (age: 28.7+/-4.2 yr; height: 181.0+/-4.2 cm; weight: 71.0+/-5.2 kg; body fat: 10.2+/-2.4%), during basic pre-season training. The athletes trained on five days (160 km per day) and respected one rest-day (33 km). The food of the cyclists, which was chosen by the riders themselves, was weighed and recorded for six days, the protocols were analysed through the PRODI 4.3 EXPERT database. The daily energy intake which averaged 13.5 MJ (59% carbohydrates, 19% proteins, and 21% fat), was compared to the mean daily consumption of energy (19.1 MJ), which was calculated from the basal metabolic rate and the energy turnover while training (directly measured through the SRM Training system). The daily energy expenditure was 30% higher than the daily energy intake. The analysis of the food diary showed that these experienced riders composed a carbohydrate-rich and low-fat diet by themselves as recommended for high-performance endurance athletes. When compared to nutritional guidelines, the composition of the diet in the present study can be considered as adequate.