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Breakthrough methods in machine learning (ML), protein structure prediction, and novel ultrafast structural aligners are revolutionizing structural biology. Obtaining accurate models of proteins and annotating their functions on a large scale is no longer limited by time and resources. The most recent method to be top ranked by the Critical Assessment of Structure Prediction (CASP) assessment, AlphaFold 2 (AF2), is capable of building structural models with an accuracy comparable to that of experimental structures. Annotations of 3D models are keeping pace with the deposition of the structures due to advancements in protein language models (pLMs) and structural aligners that help validate these transferred annotations. In this review we describe how recent developments in ML for protein science are making large-scale structural bioinformatics available to the general scientific community.
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Aprendizado de Máquina , Proteínas , Proteínas/química , Biologia Computacional/métodos , Conformação ProteicaRESUMO
The adult nervous system has a limited capacity to regenerate after accidental damage. Post-injury functional restoration requires proper targeting of the injured axon to its postsynaptic cell. Although the initial response to axonal injury has been studied in great detail, it is rather unclear what controls the re-establishment of a functional connection. Using the posterior lateral microtubule neuron in Caenorhabditis elegans, we found that after axotomy, the regrowth from the proximal stump towards the ventral side and accumulation of presynaptic machinery along the ventral nerve cord correlated to the functional recovery. We found that the loss of insulin receptor DAF-2 promoted 'ventral targeting' in a DAF-16-dependent manner. We further showed that coordinated activities of DAF-16 in neuron and muscle promoted 'ventral targeting'. In response to axotomy, expression of the Netrin receptor UNC-40 was upregulated in the injured neuron in a DAF-16-dependent manner. In contrast, the DAF-2-DAF-16 axis contributed to the age-related decline in Netrin expression in muscle. Therefore, our study revealed an important role for insulin signaling in regulating the axon guidance molecules during the functional rewiring process.
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Axônios/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Moléculas de Adesão Celular/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Netrinas/metabolismo , Animais , Orientação de Axônios , Proteínas de Caenorhabditis elegans/genética , Moléculas de Adesão Celular/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica , Microtúbulos/metabolismo , Fatores de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Netrina/metabolismo , Netrinas/genética , Neurônios/metabolismo , Transdução de SinaisRESUMO
Early diagnosis of post-traumatic osteoarthritis (PTOA) is critical for designing better treatments before the degradation becomes irreversible. We utilized multimodal high-resolution imaging to investigate early-stage deterioration in articular cartilage and the subchondral bone plate from a sub-critical impact to the knee joint, which initiates PTOA. The knee joints of 12 adult rabbits were mechanically impacted once on the femoral articular surface to initiate deterioration. At 2- and 14-week post-impact surgery, cartilage-bone blocks were harvested from the impact region in the animals (N = 6 each). These blocks were assessed for deterioration using polarized light microscopy (PLM), microcomputed tomography (µCT), and biochemical analysis. Statistically significant changes were noted in the impact tissues across the calcified zone (CZ) at 14 weeks post-impact: the optical retardation values in the CZ of impact cartilage had a drop of 29.0% at 14 weeks, while the calcium concentration in the CZ of impact cartilage also had a significant drop at 14 weeks. A significant reduction of 6.3% in bone mineral density (BMD) was noted in the subchondral bone plate of the impact samples at 14 weeks. At 2 weeks post-impact, only minor, non-significant changes were measured. Furthermore, the impact knees after 14 weeks had greater structural changes compared with the 2-week impact knees, indicating progressive degradation over time. The findings of this study facilitated a connection between mineralization alterations and the early deterioration of knee cartilage after a mechanical injury. In a broader context, these findings can be beneficial in improving clinical strategies to manage joint injuries.
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High-stakes non-cognitive tests frequently employ forced-choice (FC) scales to deter faking. To mitigate the issue of score ipsativity derived, many scoring models have been devised. Among them, the multi-unidimensional pairwise preference (MUPP) framework is a highly flexible and commonly used framework. However, the original MUPP model was developed for unfolding response process and can only handle paired comparisons. The present study proposes the 2PLM-RANK as a generalization of the MUPP model to accommodate dominance RANK format response. In addition, an improved stochastic EM (iStEM) algorithm is devised for more stable and efficient parameter estimation. Simulation results generally supported the efficiency and utility of the new algorithm in estimating the 2PLM-RANK when applied to both triplets and tetrads across various conditions. An empirical illustration with responses to a 24-dimensional personality test further supported the practicality of the proposed model. To further aid in the application of the new model, a user-friendly R package is also provided.
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Elongate mineral particles, including asbestos, have long been screened in talc and other mineral powders. In recent years, there has been a renewed scrutiny of talc containing asbestos due to allegations in civil litigation in the United States as well as reports, proposals, and white papers by international laboratories and government bodies related to this subject. This study demonstrates the importance of the fundamental understanding of both mineralogy and its application, using microscopy with empirical examples from conflicting analyses of the same talc powders by two independent laboratories in civil litigation in the United States. Methods include polarized light microscopy (PLM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) in the accurate measurement of morphological, optical, compositional, and structural data to characterize mineral-based samples. Discussions in this study include: 1) contrasting the interlaboratory findings of amphibole and amphibole asbestos by PLM and TEM using various preparation techniques, 2) the use of multiple analytical tools on a singular particle for identification, 3) the misidentification of anthophyllite asbestos by inexpert use of electron diffraction using TEM, and 4) the misidentification of chrysotile in talc by PLM. These examples emphasize the importance of not only maintaining the existing requirements, but of the need for even more rigorous analytical requirements in routine monitoring of elongate mineral particles that may occur in mineral-based powders.
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Amiantos Anfibólicos , Amianto , Amiantos Anfibólicos/toxicidade , Talco/toxicidade , Pós , Laboratórios , Minerais/toxicidadeRESUMO
NEW FINDINGS: What is the central question of this study? Use of the passive leg movement (PLM) test, a non-invasive assessment of microvascular function, is on the rise. However, PLM reliability in men has not been adequately investigated, nor has such reliability data, in men, been compared to the most commonly employed vascular function assessment, flow-mediated vasodilation (FMD). What is the main finding and its importance? PLM is a reliable method to assess vascular function in men, and is comparable to values previously reported for PLM in women, and for FMD. Given the importance of vascular function as a predictor of cardiovascular disease risk, these data support the utility of PLM as a clinically relevant measurement. ABSTRACT: Although vascular function is an independent predictor of cardiovascular disease risk, and therefore has significant prognostic value, there is currently not a single clinically accepted method of assessment. The passive leg movement (PLM) assessment predominantly reflects microvascular endothelium-dependent vasodilation and can identify decrements in vascular function with advancing age and pathology. Reliability of the PLM model was only recently determined in women, and has not been adequately investigated in men. Twenty healthy men (age: 27 ± 2 year) were studied on three separate experimental days, resulting in three within-day and three between-day trials. The hyperemic response to PLM was assessed with Doppler ultrasound, and expressed as the absolute peak in leg blood flow (LBFpeak ), change from baseline to peak (ΔLBFpeak ), absolute area under the curve (LBFAUC ), and change in AUC from baseline (ΔLBFAUC ). PLM-induced hyperemia yielded within-day coefficients of variation (CV) from 10.9 to 22.9%, intraclass correlation coefficients (ICC) from 0.82 to 0.90, standard error of the measurement (SEM) from 8.3 to 17.2%, and Pearson's correlation coefficients (r) from 0.56 to 0.81. Between-day assessments of PLM hyperemia resulted in CV from 14.4 to 25%, ICC from 0.75 to 0.87, SEM from 9.8 to 19.8%, and r from 0.46 to 0.75. Similar to previous reports in women, the hyperemic responses to PLM in men display moderate-to-high reliability, and are comparable to reliability data for brachial artery flow mediated vasodilation. These positive reliability findings further support the utility of PLM as a clinical measurement of vascular function and cardiovascular disease risk.
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Doenças Cardiovasculares , Hiperemia , Adulto , Artéria Braquial , Endotélio Vascular , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Movimento/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Reprodutibilidade dos Testes , Vasodilatação/fisiologiaRESUMO
In this case study, distress mechanism(s) of a concrete structure in the saturated and unsaturated zones of the foundation were investigated. This research was performed using a stereomicroscope, polarised light microscopy (PLM), and a limited study using a scanning electron microscope (SEM) with backscattered electron (BSE). Results of this study showed that concrete cores extracted from both the saturated and unsaturated zones of the foundation exhibited severe to moderate concrete distress, but the cause of the distress/cracking in the concrete was not related to Alkali-Carbonate Reaction (ACR) as was initially suspected. While the damage to the concrete extracted from the structure above the saturated zone of the foundation was caused by a combination of Alkali-Silica Reaction (ASR) and freeze-thaw deterioration, concrete distress in the saturated zone of the foundation was caused primarily by ASR of shale particles in the natural sand fine aggregate. The sand also contained traces of chert particles with ASR. Limited ASR was seen in the crushed gravel coarse aggregate siliceous limestone, dolomitic limestone, and chert particles. Results of this case study showed that siliceous shale particles in the fine aggregate caused detrimental ASR damage to the concrete, and thus caution needs to be exercised when aggregate containing shale is used in concrete.
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Carbonato de Cálcio , Areia , Álcalis , Dióxido de SilícioRESUMO
In order to identify peripheral biomarkers of impaired oxidative metabolism during exercise following a 10-day bed rest, 10 males performed an incremental exercise (to determine peak pulmonary VÌO2 (VÌO2 p)) and moderate-intensity exercises, before (PRE) and after (POST) bed rest. Blood flow response was evaluated in the common femoral artery by Eco-Doppler during 1 min of passive leg movements (PLM). The intramuscular matching between O2 delivery and O2 utilization was evaluated by near-infrared spectroscopy (NIRS). Mitochondrial respiration was evaluated ex vivo by high-resolution respirometry in isolated muscle fibres, and in vivo by NIRS by the evaluation of skeletal muscle VÌO2 (VÌO2 m) recovery kinetics. Resting VÌO2 m was estimated by NIRS. Peak VÌO2 p was lower in POST vs. PRE. The area under the blood flow vs. time curve during PLM was smaller (P = 0.03) in POST (274 ± 233 mL) vs. PRE (427 ± 291). An increased (P = 0.03) overshoot of muscle deoxygenation during a metabolic transition was identified in POST. Skeletal muscle citrate synthase activity was not different (P = 0.11) in POST (131 ± 16 nmol min-1 mg-1 ) vs. PRE (138 ± 19). Maximal ADP-stimulated mitochondrial respiration (66 ± 18 pmol s-1 mg-1 (POST) vs. 72 ± 14 (PRE), P = 0.41) was not affected by bed rest. Apparent Km for ADP sensitivity of mitochondrial respiration was reduced in POST vs. PRE (P = 0.04). The VÌO2 m recovery time constant was not different (P = 0.79) in POST (22 ± 6 s) vs. PRE (22 ± 6). Resting VÌO2 m was reduced by 25% in POST vs. PRE (P = 0.006). Microvascular-endothelial function was impaired following a 10-day bed rest, whereas mitochondrial mass and function (both in vivo and ex vivo) were unaffected or slightly enhanced. KEY POINTS: Ten days of horizontal bed rest impaired in vivo oxidative function during exercise. Microvascular impairments were identified by different methods. Mitochondrial mass and mitochondrial function (evaluated both in vivo and ex vivo) were unchanged or even improved (i.e. enhanced mitochondrial sensitivity to submaximal [ADP]). Resting muscle oxygen uptake was significantly lower following bed rest, suggesting that muscle catabolic processes induced by bed rest/inactivity are less energy-consuming than anabolic ones.
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Repouso em Cama , Consumo de Oxigênio , Humanos , Masculino , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo , RespiraçãoRESUMO
Two-photon Phosphorescence Lifetime Microscopy (2PLM) is an emerging nonlinear optical technique that has great potential to improve our understanding of the basic biology underlying human health and disease. Although analogous to 2-photon Fluorescence Lifetime Imaging Microscopy (2P-FLIM), the contrast in 2PLM is fundamentally different from various intensity-based forms of imaging since it is based on the lifetime of an excited state and can be regarded as a "functional imaging" technique. 2PLM signal originates from the deactivation of the excited triplet state (phosphorescence) [1, 2]. Typically, this triplet state is a much longer-lived excited state than the singlet excited state resulting in phosphorescence emission times of microseconds to milliseconds at room temperature as opposed to nanoseconds for fluorescence emission [3]. The long-lived nature of the triplet state makes it highly sensitive to quenching molecules in the surrounding environment such as biomolecular oxygen (O2). Therefore, 2PLM can provide not only information on the distribution pattern of the probe in the sample (via intensity) but also determine the local oxygen tension (via phosphorescence lifetime quenching) [1]. The ability to create three-dimensional optical sections in the plane of focus within a thick biological specimen while maintaining relatively low phototoxicity due to the use of near-infrared wavelengths for two-photon excitation gives 2PLM powerful advantages over other techniques for longitudinal imaging and monitoring of oxygen within living organisms [4]. In this chapter, we will provide background on the development of 2PLM, discuss the most common oxygen sensing measurement methods and concepts, and explain the general principles and optical configuration of a 2PLM system. We also discuss the key characteristics and strategies for improvement of the technique. Finally, we will present an overview of the current primary scientific literature of how 2PLM has been used for oxygen sensing in biological applications and how this technique is improving our understanding of the basic biology underlying several areas of human health.
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Oxigênio , Fótons , Humanos , Microscopia de FluorescênciaRESUMO
Lisofylline (LSF) is an anti-inflammatory molecule with high aqueous solubility and rapid metabolic interconversion to its parent drug, pentoxifylline (PTX) resulting in very poor pharmacokinetic (PK) parameters, necessitating high dose and dosing frequency. In the present study, we resolved the physicochemical and pharmacokinetic limitations associated with LSF and designed its oral dosage form as a tablet for effective treatment in type 1 diabetes (T1D). Self-assembling polymeric micelles of LSF (lisofylline-linoleic acid polymeric micelles (LSF-LA PLM)) were optimized for scale-up (6 g batch size) and lyophilized followed by compression into tablets. Powder blend and tablets were evaluated as per USP. LSF-LA PLM tablet so formed was evaluated for in vitro release in simulated biological fluids (with enzymes) and for cell viability in MIN-6 cells. LSF-LA PLM in tablet formulation was further evaluated for intestinal permeability (in situ) along with LSF and LSF-LA self-assembled micelles (SM) as controls in a rat model using single-pass intestinal perfusion (SPIP) study. SPIP studies revealed 1.8-fold higher oral absorption of LSF-LA from LSF-LA PLM as compared to LSF-LA SM and ~5.9-fold higher than LSF (alone) solution. Pharmacokinetic studies of LSF-LA PLM tablet showed greater Cmax than LSF, LSF-LA, and LSF-LA PLM. Designed facile LSF-LA PLM tablet dosage form has potential for an immediate decrease in the postprandial glucose levels in patients of T1D.
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Diabetes Mellitus Tipo 1/metabolismo , Jejuno/metabolismo , Ácido Linoleico/farmacocinética , Nanopartículas/metabolismo , Pentoxifilina/análogos & derivados , Perfusão/métodos , Administração Oral , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Formas de Dosagem , Jejuno/efeitos dos fármacos , Ácido Linoleico/administração & dosagem , Ácido Linoleico/síntese química , Masculino , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Pentoxifilina/administração & dosagem , Pentoxifilina/síntese química , Pentoxifilina/farmacocinética , Ratos , Ratos Wistar , ComprimidosRESUMO
PURPOSE: To evaluate whole knee joint tractography, including articular cartilage, ligaments, meniscus, and growth plate using diffusion tensor imaging (DTI) at microscopic resolution. METHODS: Three rat knee joints were scanned using a modified 3D diffusion-weighted spin echo pulse sequence with 90- and 45-µm isotropic spatial resolution at 9.4T. The b values varied from 250 to 1250 s/mm2 with 4 times undersampling in phase directions. Fractional anisotropy (FA) and mean diffusivity (MD) were compared at different spatial resolution and b values. Tractography was evaluated at multiple b values and angular resolutions in different connective tissues, and compared with conventional histology. The mean tract length and tract volume in various types of tissues were also quantified. RESULTS: DTI metrics (FA and MD) showed consistent quantitative results at 90- and 45-µm isotropic spatial resolutions. Tractography of various connective tissues was found to be sensitive to the spatial resolution, angular resolution, and diffusion weightings. Higher spatial resolution (45 µm) supported tracking the cartilage collagen fiber tracts from the superficial zone to the deep zone, in a continuous and smooth progression in the transitional zone. Fiber length and fiber volume in the growth plate were strongly dependent on angular resolution and b values, whereas tractography in ligaments was found to be less dependent on spatial resolution. CONCLUSION: High spatial and angular resolution DTI and diffusion tractography can be valuable for knee joint research because of its visualization capacity for collagen fiber orientations and quantitative evaluation of tissue's microscopic properties.
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Ligamento Cruzado Anterior/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Processamento de Imagem Assistida por Computador/métodos , Joelho de Quadrúpedes/diagnóstico por imagem , Animais , Anisotropia , RatosRESUMO
PURPOSE: Recent studies found that the non-contact screening device SleepMinder (ResMed Sensor Technologies, Dublin, Ireland) detects sleep-disordered breathing (SDB) with high diagnostic accuracy in cohorts suspected of this disorder. However, it was reported that in patients with periodic limb movement in sleep (PLMS), this non-contact device overestimates the apnea-hypopnea index (AHI). We aimed to overcome this limitation by introducing the novel sleep disorder index (SDI) which is sum of the AHI and the period limb movement index (PLMI). METHODS: Between January 2011 and December 2013, we studied a mixed cohort of 57 patients (31 OSA, 19 PLMS). The easy-to-use non-contact device emits a very weak electromagnetic radiation and detects body movement by measuring the Doppler effect. We interpreted the device-generated movement index as the SDI and validated the diagnostic accuracy against simultaneous application of the gold-standard polysomnography (PSG). RESULTS: We found that the SDI of the non-contact device correlated well with the sum of AHI and PLMI derived from PSG (r = 0.79, p = 0.01). For PSG-derived SDI cutoff ≥ 15/h, we obtained a sensitivity of 92.2% and a specificity of 95.8%. Positive likelihood ratio was 23.3 and negative likelihood ratio 0.03. CONCLUSIONS: The studied non-contact screening device detects accurately the combination of the sleep disorders SDB and/or PLM. However, further testing is required in order to specify the nature of the underlying sleep disorder. At the current stage of algorithm development, the clinical strength is that the studied non-contact device can be used as a rule-out screening device for SDB and PLM.
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Síndrome da Mioclonia Noturna/complicações , Síndrome da Mioclonia Noturna/diagnóstico , Síndromes da Apneia do Sono/complicações , Síndromes da Apneia do Sono/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Reprodutibilidade dos Testes , SonoRESUMO
Restless legs syndrome is a frequent neurological disorder with potentially serious and highly distressing treatment complications. The role and potential implications of periodic leg movements during sleep range from being a genetic risk marker for restless legs syndrome to being a cardiovascular risk factor. The diagnosis of restless legs syndrome in patients with daytime movement disorders is challenging and restless legs syndrome needs to be differentiated from other sleep-related movement disorders. This article provides an update on the diagnosis of restless legs syndrome as an independent disorder and the role of periodic leg movements and reviews the association of restless legs syndrome with Parkinson's disease and other movement disorders. © 2017 International Parkinson and Movement Disorder Society.
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Transtornos dos Movimentos/fisiopatologia , Síndrome da Mioclonia Noturna/diagnóstico , Síndrome das Pernas Inquietas/diagnóstico , Diagnóstico Diferencial , Distonia/complicações , Distonia/fisiopatologia , Tremor Essencial/complicações , Tremor Essencial/fisiopatologia , Ataxia de Friedreich/complicações , Ataxia de Friedreich/fisiopatologia , Humanos , Doença de Huntington/complicações , Doença de Huntington/fisiopatologia , Transtornos dos Movimentos/complicações , Síndrome da Mioclonia Noturna/complicações , Síndrome da Mioclonia Noturna/fisiopatologia , Doença de Parkinson/complicações , Doença de Parkinson/fisiopatologia , Polissonografia , Qualidade de Vida , Síndrome das Pernas Inquietas/complicações , Síndrome das Pernas Inquietas/fisiopatologia , Índice de Gravidade de Doença , Ataxias Espinocerebelares/complicações , Ataxias Espinocerebelares/fisiopatologia , Síndrome de Tourette/complicações , Síndrome de Tourette/fisiopatologiaRESUMO
BACKGROUND: Periodic leg movements (PLM) during sleep (PLMS) are considered strongly related to restless legs syndrome (RLS), and are associated with polymorphisms in RLS risk genes. Various software for automatic analysis of PLMS are available, but only few of them have been validated. Aim of this study was to validate a leg movements count and analysis integrated in a commercially available polysomnography (PSG) system against manual scoring. METHODS: Twenty RLS patients with a PLMS index > 20/h and 20 controls with a PLMS index < 5/h were included. Manual and computerized scoring of leg movements (LM) and PLM was performed according to the standard American Academy of Sleep Medicine (AASM) criteria. LM and PLM indices during sleep and wakefulness, the rate of PLMS associated with respiratory events, intermovement interval and periodicity indices were manually and automatically scored. RESULTS: The correlation between manual and computerized scoring was high for all investigated parameters (Spearman correlation coefficients 0.751-0.996, p < 0.001; intraclass correlation coefficients 0.775-0.999, p < 0.001). Bland-Altman plots showed high agreement between manual and automatic analysis. CONCLUSIONS: This study validated an automatic LM count and PLM analysis against the gold standard manual scoring according to AASM criteria. The data demonstrate that the software used in this study has an outstanding performance for computerized LM and PLM scoring, and LM and PLM indices generated with this software can be reliably integrated in the routine PSG report. This automatic analysis is also an excellent tool for research purposes.
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Algoritmos , Perna (Membro)/fisiopatologia , Polissonografia/métodos , Síndrome das Pernas Inquietas/fisiopatologia , Índice de Gravidade de Doença , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Key to the understanding of the principles of physiological and structural acclimatization to changes in the balance between energy supply (represented by substrate and oxygen delivery, and mitochondrial oxidative phosphorylation) and energy demand (initiated by neuronal activity) is to determine the controlling variables, how they are sensed and the mechanisms initiated to maintain the balance. The mammalian brain depends completely on continuous delivery of oxygen to maintain its function. We hypothesized that tissue oxygen is the primary sensed variable. In this study two-photon phosphorescence lifetime microscopy (2PLM) was used to determine and define the tissue oxygen tension field within the cerebral cortex of mice to a cortical depth of between 200-250 µm under normoxia and acute hypoxia (FiO2 = 0.10). High-resolution images can provide quantitative distributions of oxygen and intercapillary oxygen gradients. The data are best appreciated by quantifying the distribution histogram that can then be used for analysis. For example, in the brain cortex of a mouse, at a depth of 200 µm, tissue oxygen tension was mapped and the distribution histogram was compared under normoxic and mild hypoxic conditions. This powerful method can provide for the first time a description of the delivery and availability of brain oxygen in vivo.
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Encéfalo/metabolismo , Hipóxia/metabolismo , Medições Luminescentes/métodos , Oxigênio/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Química Encefálica , Mapeamento Encefálico/métodos , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Hipóxia/diagnóstico por imagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia/métodos , Oxigênio/análise , Pressão ParcialRESUMO
BACKGROUND: Restless legs syndrome (RLS) has been associated with insomnia, decreased quality of life, and increased morbidity and mortality in end-stage renal disease. This randomized controlled trial investigated effects of rotigotine in patients with RLS and end-stage renal disease. STUDY DESIGN: Double-blind placebo-controlled study. SETTING & PARTICIPANTS: Adults with moderate to severe RLS (International RLS Study Group Rating Scale [IRLS] ≥ 15) and Periodic Limb Movement Index (PLMI) ≥ 15 who were receiving thrice-weekly hemodialysis enrolled from sites in the United States and Europe. INTERVENTION: Following randomization and titration (≤21 + 3 days) to optimal-dose rotigotine (1-3mg/24 h) or placebo, patients entered a 2-week maintenance period. Polysomnography was performed at baseline and the end of maintenance. OUTCOMES & MEASUREMENTS: Primary efficacy outcome: reduction in PLMI, assessed by ratio of PLMI at end of maintenance to baseline. Secondary/other outcomes (P values exploratory) included mean changes from baseline in PLMI, IRLS, and Clinical Global Impression item 1 (CGI-1 [severity of illness]) score. RESULTS: 30 patients were randomly assigned (rotigotine, 20; placebo, 10); 25 (15; 10) completed the study with evaluable data. Mean (SD) PLMI ratio (end of maintenance to baseline) was 0.7±0.4 for rotigotine and 1.3±0.7 for placebo (analysis of covariance treatment ratio, 0.44; 95% CI, 0.22 to 0.88; P=0.02). Numerical improvements were observed with rotigotine versus placebo in IRLS and CGI-1 (least squares mean treatment differences of -6.08 [95% CI, -12.18 to 0.02; P=0.05] and -0.81 [95% CI, -1.94 to 0.33; P=0.2]). 10 of 15 rotigotine and 2 of 10 placebo patients were CGI-1 responders (≥50% improvement). Hemodialysis did not affect unconjugated rotigotine concentrations. The most common adverse events (≥2 patients) were nausea (rotigotine, 4 [20%]; placebo, 0); vomiting (3 [15%]; 0); diarrhea (1 [5%]; 2 [20%]); headache (2 [10%]; 0); dyspnea (2 [10%]; 0); and hypertension (2 [10%]; 0). LIMITATIONS: Small sample size and short duration. CONCLUSIONS: Rotigotine improved periodic limb movements and RLS symptoms in the short term among ESRD patients requiring hemodialysis in a small-scale study. No dose adjustments are necessary for hemodialysis patients.
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Agonistas de Dopamina/uso terapêutico , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Diálise Renal , Síndrome das Pernas Inquietas/tratamento farmacológico , Síndrome das Pernas Inquietas/etiologia , Adolescente , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tetra-Hidronaftalenos , Tiofenos , Adulto JovemRESUMO
OBJECTIVES: Dental peri-implantitis is characterized by a multifactorial etiology. The role of metal elements as an etiological factor for peri-implantitis is still unclear. The aim of this study was to investigate the incidence of metal elements in bone and mucosal tissues around dental Grade 4 CP titanium implants with signs of peri-implantitis in human patients. METHODS: In this prospective pilot study, all patients were enrolled consecutively in two study centers. Bone and soft tissue samples of patients with peri-implantitis with indication for explantation were analyzed for the incidence of different elements (Ca, P, Ti, Fe) by means of synchrotron radiation X-ray fluorescence spectroscopy (SRXRF) and polarized light microscopy (PLM). The existence of macrophages and lymphocytes in the histologic specimens was analyzed. RESULTS: Biopsies of 12 patients (seven bone samples, five mucosal samples) were included and analyzed. In nine of the 12 samples (75%), the SRXRF examination revealed the existence of titanium (Ti) and an associated occurrence with Iron (Fe). Metal particles were detected in peri-implant soft tissue using PLM. In samples with increased titanium concentration, lymphocytes were detected, whereas M1 macrophages were predominantly seen in samples with metal particles. CONCLUSION: Titanium and Iron elements were found in soft and hard tissue biopsies retrieved from peri-implantitis sites. Further histologic and immunohistochemical studies need to clarify which specific immune reaction metal elements/particles induce in dental peri-implant tissue.
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Implantes Dentários/efeitos adversos , Peri-Implantite/etiologia , Titânio/efeitos adversos , Idoso , Processo Alveolar/química , Feminino , Gengiva/química , Humanos , Ferro/efeitos adversos , Ferro/análise , Masculino , Microscopia de Polarização , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Espectrometria por Raios X , Titânio/análiseRESUMO
This paper describes our conceptual framework of closed-loop lifecycle information sharing for product-service in the Internet of Things (IoT). The framework is based on the ontology model of product-service and a type of IoT message standard, Open Messaging Interface (O-MI) and Open Data Format (O-DF), which ensures data communication. (1) BACKGROUND: Based on an existing product lifecycle management (PLM) methodology, we enhanced the ontology model for the purpose of integrating efficiently the product-service ontology model that was newly developed; (2) METHODS: The IoT message transfer layer is vertically integrated into a semantic knowledge framework inside which a Semantic Info-Node Agent (SINA) uses the message format as a common protocol of product-service lifecycle data transfer; (3) RESULTS: The product-service ontology model facilitates information retrieval and knowledge extraction during the product lifecycle, while making more information available for the sake of service business creation. The vertical integration of IoT message transfer, encompassing all semantic layers, helps achieve a more flexible and modular approach to knowledge sharing in an IoT environment; (4) Contribution: A semantic data annotation applied to IoT can contribute to enhancing collected data types, which entails a richer knowledge extraction. The ontology-based PLM model enables as well the horizontal integration of heterogeneous PLM data while breaking traditional vertical information silos; (5) CONCLUSION: The framework was applied to a fictive case study with an electric car service for the purpose of demonstration. For the purpose of demonstrating the feasibility of the approach, the semantic model is implemented in Sesame APIs, which play the role of an Internet-connected Resource Description Framework (RDF) database.
RESUMO
Runx1 is a transcription factor essential for definitive hematopoiesis. In all vertebrates, the Runx1 gene is transcribed from two promoters: a proximal promoter (P2), and a distal promoter (P1). We previously found that runx1 expression in a specific hematopoietic cell population in zebrafish embryos depends on cohesin. Here we show that zebrafish runx1 is directly bound by cohesin and CCCTC binding factor (CTCF) at the P1 and P2 promoters, and within the intron between P1 and P2. Cohesin initiates expression of runx1 in the posterior lateral mesoderm and influences promoter use, while CTCF represses its expression in the newly emerging cells of the tail bud. The intronic binding sites for cohesin and CTCF coincide with histone modifications that confer enhancer-like properties, and two of the cohesin/CTCF sites behaved as insulators in an in vivo assay. The identified cohesin and CTCF binding sites are likely to be cis-regulatory elements (CREs) for runx1 since they also recruit RNA polymerase II (RNAPII). CTCF depletion excluded RNAPII from two intronic CREs but not the promoters of runx1. We propose that cohesin and CTCF have distinct functions in the regulation of runx1 during zebrafish embryogenesis, and that these regulatory functions are likely to involve runx1 intronic CREs. Cohesin (but not CTCF) depletion enhanced RUNX1 expression in a human leukemia cell line, suggesting conservation of RUNX1 regulation through evolution.
Assuntos
Proteínas de Ciclo Celular/genética , Proteínas Cromossômicas não Histona/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Proteínas Repressoras/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Animais , Fator de Ligação a CCCTC , Linhagem Celular Tumoral , Embrião não Mamífero , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Mesoderma , Regiões Promotoras Genéticas , Peixe-Zebra/genética , CoesinasRESUMO
Reasonable suspicion has accumulated that inhaled nano-scale particulate matter influences the biophysical function of the pulmonary surfactant system. Hence, it is evident to provide novel insights into the extent and mechanisms of nanoparticle-surfactant interactions in order to facilitate the fabrication of safe nanomedicines suitable for pulmonary applications. Negatively- and positively-charged poly(styrene) nanoparticles (diameters of ~100nm) served as model carriers. Nanoparticles were incubated with several synthetic and naturally-derived pulmonary surfactants to characterize the sensitivity of each preparation to biophysical inactivation. Changes in surface properties (i.e. adsorption and dynamic surface tension behavior) were monitored in a pulsating bubble surfactometer. Both nanoparticle formulations revealed a dose-dependent influence on the biophysical behavior of all investigated pulmonary surfactants. However, the surfactant sensitivity towards inhibition depended on both the carrier type, where negatively-charged nanoparticles showed increased inactivation potency compared to their positively-charged counterparts, and surfactant composition. Among the surfactants tested, synthetic mixtures (i.e. phospholipids, phospholipids supplemented with surfactant protein B, and Venticute®) were more susceptible to surface-activity inhibition as the more complex naturally-derived preparations (i.e. Alveofact® and large surfactant aggregates isolated from rabbit bronchoalveolar lavage fluid). Overall, nanoparticle characteristics and surfactant constitution both influence the extent of biophysical inhibition of pulmonary surfactants.