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The statistical analysis of omics data poses a great computational challenge given their ultra-high-dimensional nature and frequent between-features correlation. In this work, we extended the iterative sure independence screening (ISIS) algorithm by pairing ISIS with elastic-net (Enet) and 2 versions of adaptive elastic-net (adaptive elastic-net (AEnet) and multistep adaptive elastic-net (MSAEnet)) to efficiently improve feature selection and effect estimation in omics research. We subsequently used genome-wide human blood DNA methylation data from American Indian participants in the Strong Heart Study (n = 2235 participants; measured in 1989-1991) to compare the performance (predictive accuracy, coefficient estimation, and computational efficiency) of ISIS-paired regularization methods with that of a bayesian shrinkage and traditional linear regression to identify an epigenomic multimarker of body mass index (BMI). ISIS-AEnet outperformed the other methods in prediction. In biological pathway enrichment analysis of genes annotated to BMI-related differentially methylated positions, ISIS-AEnet captured most of the enriched pathways in common for at least 2 of all the evaluated methods. ISIS-AEnet can favor biological discovery because it identifies the most robust biological pathways while achieving an optimal balance between bias and efficient feature selection. In the extended SIS R package, we also implemented ISIS paired with Cox and logistic regression for time-to-event and binary endpoints, respectively, and a bootstrap approach for the estimation of regression coefficients.
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Algoritmos , Índice de Massa Corporal , Metilação de DNA , Epigenômica , Humanos , Epigenômica/métodos , Feminino , Masculino , Teorema de Bayes , Pessoa de Meia-Idade , Epigênese Genética , Idoso , Biomarcadores/sangueRESUMO
BACKGROUND: In response to emergencies, such as wildfires, donations of pharmaceuticals often occur. These donations can be given directly by governments, to non-governmental organizations as corporate donations, or by private entities that donate to individual health institutions. OBJECTIVE: This paper aimed to collect, review and analyze pharmaceutical product donations received during the natural disaster caused by wildfires in the San Luis province, Argentina, in September and October 2020. METHODS: A descriptive, cross-sectional, and retrospective study was performed. An introductory approach to good donation practices was also carried out. Medicines were classified and in the case of products that were not suitable for administration, these were discarded. RESULTS: A total of 15,593 units were segregated, of which 52.8% were over-the-counter products and 47.2% were prescription drugs. 86.3% (13,467 units) were accepted, while 13.7% (2126 units) had to be destroyed. The value of donations totaled USD 16,544. The analysis of the results showed that an important part of the donations was irrelevant in the emergency context. Donations were also received in incorrect amounts, which generated a large stock of medicines that couldn't be used. In emergencies, inappropriate donations create additional work during sorting, storage, and distribution, increasing the time professionals need to complete tasks. This extra work can easily overwhelm limited human and logistical resources. CONCLUSIONS: It is important to previously evaluate the real need for donations. In addition, the distribution of donations must be done through pre-established systems and policies. Otherwise, unsolicited and unnecessary drug donations become wasteful and should therefore be avoided.
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Desastres Naturais , Medicamentos sob Prescrição , Humanos , Estudos Transversais , Emergências , Estudos RetrospectivosRESUMO
PURPOSE: 3D printing (3DP) makes it possible to obtain systems that are not achievable with current conventional methods, one of them, sustained release floating systems. Floating systems using ricobendazole (RBZ) as a model drug and a combination of polymers were designed and obtained by melt solidification printing technique (MESO-PP). METHODS: Four different MESO-PP inks were formulated based on combinations of the polymers Gelucire 43/01 and Gelucire 50/13 in different ratios. For each of the formulated inks, physicochemical characterization was performed by thermal analysis (thermogravimetric analysis [TGA] and differential scanning calorimetry [DSC]), fourier transform infrared spectrophotometer (FTIR) and X-ray diffraction (XRD). Pharmaceutical characterization was performed by in vitro assays to determine pharmaceutically relevant parameters. These parameters were calculated by applying mathematical models developed to evaluate in vitro drug release profiles. On the other hand, a physiologically based pharmacokinetic (PBPK) model was developed to predict the in vivo performance of RBZ loaded in the different inks by determining the Cmax, and the AUC0-∞. RESULTS: By increasing the proportion of Gelucire 50/13 co-surfactant in the mixtures (the proportion in Ink 1 was 33%, while the proportion in Ink 4 was 80%), the dissolution capacity of RBZ increases substantially, decreasing flotation times. CONCLUSION: MESO-PP produced ink 1 (50% Gelucire 43/01, 25% Gelucire 50/13 and 25% RBZ), which has a zero-order release (RR = 0.180%/min) and the longest flotation time (545 ± 23 min), and in turn would produce a significant increase in oral absorption of the drug, with an AUC0-∞ 2.16-fold higher than that obtained in animals treated with RBZ loaded in conventional tablets.
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Excipientes , Tinta , Albendazol/análogos & derivados , Animais , Preparações de Ação Retardada/química , Excipientes/química , Polímeros , Impressão Tridimensional , Tensoativos , ComprimidosRESUMO
Frames and framing make one dimension of a decision problem particularly salient. In the simplest case, frames <i>prime</i> responses (as in, e.g., the Asian disease paradigm, where the gain frame primes risk-aversion and the loss frame primes risk-seeking). But in more complicated situations frames can function reflectively, by making salient particular reason-giving aspects of a thing, outcome, or action. For Shakespeare's Macbeth, for example, his feudal commitments are salient in one frame, while downplayed in another in favor of his personal ambition. The role of frames in reasoning can give rise to <i>rational framing effects</i>. Macbeth can prefer fulfilling his feudal duty to murdering the king, while also preferring bravely taking the throne to fulfilling his feudal duty, knowing full well that bravely taking the throne just is murdering the king. Such patterns of <i>quasi-cyclical</i> preferences can be correct and appropriate from the normative perspective of how one ought to reason. The paper explores three less dramatic types of rational framing effects: (1) Consciously framing and reframing long-term goals and short-term temptations can be important tools for self-control. (2) In the prototypical social interactions modeled by game theory, allowing for rational framing effects solves longstanding problems, such as the equilibrium selection problem and explaining the appeal of non-equilibrium solutions (e.g., the cooperative solution in the Prisoner's Dilemma). (3) Processes for resolving interpersonal conflicts and breaking discursive deadlock, because they involve internalizing multiple and incompatible ways of framing actions and outcomes, in effect create rational framing effects.
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Tomada de Decisões , Teoria dos Jogos , Humanos , Tomada de Decisões/fisiologia , Motivação , Relações Interpessoais , Estudos InterdisciplinaresRESUMO
The thoughtful and rewarding peer commentaries on my target article come from a broad range of disciplinary perspectives. I engage with the commentaries in three groups. First, I discuss the commentaries that apply my basic approach to new cases not considered in the target article. Second, I explore those that helpfully extend and refine my arguments. Finally, I offer replies to those that object either to the overall framework or to specific arguments.
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Pensamento , HumanosRESUMO
Against Clarke and Beck's proposal that the approximate number system (ANS) represents natural and rational numbers, I suggest that the experimental evidence is better accommodated by the (much weaker) thesis that the ANS represents cardinality comparisons. Cardinality comparisons do not stand in arithmetical relations and being able to apply them does not involve basic arithmetical concepts and operations.
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Cognição , Idioma , Humanos , MatemáticaRESUMO
Accurately measuring epigenetic marks such as 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) at the single-nucleotide level, requires combining data from DNA processing methods including traditional (BS), oxidative (oxBS) or Tet-Assisted (TAB) bisulfite conversion. We introduce the R package MLML2R, which provides maximum likelihood estimates (MLE) of 5-mC and 5-hmC proportions. While all other available R packages provide 5-mC and 5-hmC MLEs only for the oxBS+BS combination, MLML2R also provides MLE for TAB combinations. For combinations of any two of the methods, we derived the pool-adjacent-violators algorithm (PAVA) exact constrained MLE in analytical form. For the three methods combination, we implemented both the iterative method by Qu et al. [Qu, J., M. Zhou, Q. Song, E. E. Hong and A. D. Smith (2013): "Mlml: consistent simultaneous estimates of dna methylation and hydroxymethylation," Bioinformatics, 29, 2645-2646.], and also a novel non iterative approximation using Lagrange multipliers. The newly proposed non iterative solutions greatly decrease computational time, common bottlenecks when processing high-throughput data. The MLML2R package is flexible as it takes as input both, preprocessed intensities from Infinium Methylation arrays and counts from Next Generation Sequencing technologies. The MLML2R package is freely available at https://CRAN.R-project.org/package=MLML2R.
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Metilação de DNA/genética , Epigenômica/estatística & dados numéricos , Funções Verossimilhança , Biologia Computacional/estatística & dados numéricos , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , HumanosRESUMO
Alveolar echinococcosis is a neglected parasitic zoonosis caused by Echinococcus multilocularis. The pharmacological treatment is based on albendazole (ABZ). However, the low water solubility of the drug produces a limited dissolution rate, with the consequent failure in the treatment of the disease. Solid dispersions are a successful pharmacotechnical strategy to improve the dissolution profile of poorly water-soluble drugs. The aim of this work was to determine the in vivo efficacy of ABZ solid dispersions using poloxamer 407 as a carrier (ABZ:P407 solid dispersions (SDs)) in the murine intraperitoneal infection model for secondary alveolar echinococcosis. In the chemoprophylactic efficacy study, the ABZ suspension, the ABZ:P407 SDs and the physical mixture of ABZ and poloxamer 407 showed a tendency to decrease the development of murine cysts, causing damage to the germinal layer. In the clinical efficacy study, the ABZ:P407 SDs produced a significant decrease in the weight of murine cysts. In addition, the SDs produced extensive damage to the germinal layer. The increase in the efficacy of ABZ could be due to the improvement of water solubility and wettability of the drug due to the surfactant nature of poloxamer 407. In conclusion, this study is the basis for further research. This pharmacotechnical strategy might in the future offer novel treatment alternatives for human alveolar echinococcosis.
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Albendazol/farmacologia , Antiprotozoários/farmacologia , Portadores de Fármacos/farmacologia , Equinococose/prevenção & controle , Echinococcus multilocularis/efeitos dos fármacos , Poloxâmero/farmacologia , Animais , Feminino , CamundongosRESUMO
Controlled drug delivery aims to achieve an effective drug concentration in the action site for a desired period of time, while minimizing side effects. In this contribution, biodegradable poly(3-hydroxybutyrate) films were evaluated as a reservoir platform for dexamethasone controlled release. These systems were morphological and physicochemically characterized. In vitro release assays were performed for five different percentages of drug in the films and data were fitted by a mathematical model developed and validated by our research group. When the profiles were normalized, a single curve properly fitted all the experimental data. Using this unique curve, the dissolution efficiency (DE), the time to release a given amount of drug (tX% ), and the mean dissolution time were calculated. Furthermore, the dissolution rate, the initial dissolution rate (a%) and the intrinsic dissolution rate were determined. The a% mean value was 1.968â¯×â¯10-2% released/min, t80% was about 14â¯days, and the DE was 59.6% at 14â¯days and 66.5% at 20â¯days. After 2â¯days, when approximately 40% of the drug was released, the dissolution rate decreased about 60% respect to the initial value. The poly(3-hydroxybutyrate) platforms behaved as an appropriate system to release and control the dexamethasone delivery, suggesting that they could be an alternative to improve drug therapy.
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BACKGROUND: Environmental, economic and safety challenges motivate shift towards safer materials for food packaging. New bioactive packaging techniques, i.e. addition of essential plant oils (EOs), are gaining attention by creating barriers to protect products from spoilage. Analytical pyrolysis gas chromatography-mass spectrometry (Py-GC-MS) was used to fingerprint a bioactive polylactic acid (PLA) with polybutylene succinate (PBS) (950 g kg(-1) :50 g kg(-1) ) film extruded with variable quantities (0, 20, 50 and 100 g kg(-1) ) of Origanum vulgare EO. RESULTS: Main PLA:PBS pyrolysis products were lactide enantiomers and monomer units from the major PLA fraction and succinic acid anhydride from the PBS fraction. Oregano EO pyrolysis released cymene, terpinene and thymol/carvacrol peaks as diagnostic peaks for EO. In fact, linear correlation coefficients better than 0.950R(2) value (P < 0.001) were found between the chromatographic area of the diagnostic peaks and the amount of oregano EO in the bioplastic. CONCLUSION: The pyrolytic behaviour of a bio-based active package polymer including EO is studied in detail. Identified diagnostic compounds provide a tool to monitor the quantity of EO incorporated into the PLA:PBS polymeric matrix. Analytical pyrolysis is proposed as a rapid technique for the identification and quantification of additives within bio-based plastic matrices. © 2015 Society of Chemical Industry.
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Embalagem de Alimentos , Óleos Voláteis/química , Origanum/química , Butileno Glicóis/química , Cimenos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monoterpenos/química , Extratos Vegetais/química , Poliésteres/química , Polímeros/química , Ácido Succínico/química , Timol/químicaRESUMO
Poly(3-hydroxybutyrate) (PHB) biodegradable polymeric membranes were evaluated as platform for progesterone (Prg)-controlled release. In the design of new drug delivery systems, it is important to understand the mass transport mechanism involved, as well as predict the process kinetics. Drug release experiments were conducted and the experimental results were evaluated using engineering approaches that were extrapolated to the pharmaceutical field by our research group. Membranes were loaded with different Prg concentrations and characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). SEM images showed that membranes have a dense structure before and after the progesterone addition. DSC and FTIR allowed determining the influence of the therapeutic agent in the membrane properties. The in vitro experiments were performed using two different techniques: (A) returning the sample to the receptor solution (constant volume of the delivery medium) and (B) extracting total volume of the receptor solution. In this work, we present a simple and accurate "lumped" second-order kinetic model. This lumped model considers the different mass transport steps involved in drug release systems. The model fits very well the experimental data using any of the two experimental procedures, in the range 0 ≤ t ≤ ∞ or 0 ≤ M t ≤ M ∞. The drug release analysis using our proposed approaches is relevant for establishing in vitro-in vivo correlations in future tests in animals.
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Ácido 3-Hidroxibutírico/química , Hidroxibutiratos/química , Poliésteres/química , Progesterona/química , Varredura Diferencial de Calorimetria/métodos , Sistemas de Liberação de Medicamentos/métodos , Cinética , Microscopia Eletrônica de Varredura/métodos , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodosRESUMO
Preclinical studies show that estradiol enhances sensitization to cocaine in females by mechanisms not fully understood. These studies consistently show that ovariectomized (OVX) rats exhibit little or no sensitization to cocaine compared to OVX rats administered estradiol. In this study we varied the dose of cocaine (10, 15, and 30mg/kg), the length of cocaine treatment (from 5 to 10days) and the context of cocaine injections to determine if these factors play a role on estradiol's effects on cocaine sensitization. Because OVX rats are hormonally compromised, they are not representative of the natural state of the animal, and thus the physiological context of these studies remains unclear. To address this issue, we blocked ERs in gonadally intact females by icv administration of the antiestrogen ICI-182,780. Varying the dose or length of exposure to cocaine does not alter estradiol's effect on cocaine sensitization. In contrast, a highly context-dependent sensitization protocol results in robust sensitization even in OVX rats. Interestingly, using this protocol, sensitization in OVX rats diminished with time, suggesting that estradiol is necessary for the maintenance of cocaine sensitization. Blocking brain ERs with ICI completely abolishes the development and expression of cocaine sensitization in gonadally intact female rats, even when tested in a highly context-dependent sensitization protocol. Given these findings, we propose that activation of brain ERs is required for the development and maintenance of sensitization and CPP.
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Cocaína/farmacologia , Condicionamento Operante/efeitos dos fármacos , Sinais (Psicologia) , Inibidores da Captação de Dopamina/farmacologia , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Receptores de Estrogênio/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Condicionamento Operante/fisiologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Estradiol/análogos & derivados , Estradiol/metabolismo , Feminino , Fulvestranto , Atividade Motora/efeitos dos fármacos , Ovariectomia , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/antagonistas & inibidoresRESUMO
Objective: The study of the potential intermediate effect of several variables on the association between an exposure and a time-to-event outcome is a question of interest in epidemiologic research. However, to our knowledge, no tools have been developed for the evaluation of multiple correlated mediators in a survival setting. Methods: In this work, we extended the multimediate algorithm, which conducts mediation analysis in the context of multiple uncausally correlated mediators, to a time-to-event setting using the semiparametric additive hazards model. We theoretically demonstrated that, under certain assumptions, indirect, direct and total effects can be calculated using the counterfactual framework with collapsible survival models. We also adapted the algorithm to accommodate exposure-mediator interactions. Results and conclusions: Using simulations, we demonstrated that our algorithm performs better than the product of coefficients method, even for uncorrelated mediators. The additive hazards model quantifies the effects as rate differences, which constitute a measure of impact, with applications that can be highly informative for public health. Our algorithm can be found in the R package multimediate, which is available in Github.
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Sepsis is a major health problem in the United States with high incidence and elevated patient care cost. Using an animal model of sepsis, cecum ligation, and puncture, we observed that mice became rapidly hypothermic reaching a threshold temperature of 28 °C within 5-10 h after initiation of the insult, resulting in a reliable predictor of mortality, which occurred within 30-72 h of the initial procedure. We also observed that the inflammatory gene expression in lung and liver developed early within 1-2 h of the insult, reaching maximum levels at 6 h, followed by a decline, approaching basal conditions within 20 h. This decrease in inflammatory gene expression at 20 h after cecal ligation and puncture was not due to resolution of the insult but rather was an immune dysfunction stage that was demonstrated by the inability of the animal to respond to a secondary external inflammatory stimulus. Removal of the injury source, ligated cecum, within 6 h of the initial insult resulted in increased survival, but not after 20 h of cecal ligation and puncture. We concluded that the therapeutic window for resolving sepsis is early after the initial insult and coincides with a stage of hyperinflammation that is followed by a condition of innate immune dysfunction in which reversion of the outcome is no longer possible.
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Regulação da Expressão Gênica/imunologia , Imunidade Inata , Sepse/imunologia , Sepse/terapia , Animais , Humanos , Inflamação/imunologia , Inflamação/patologia , Masculino , Camundongos , Sepse/economia , Sepse/epidemiologia , Sepse/patologia , Fatores de Tempo , Estados Unidos/epidemiologiaRESUMO
Altered DNA methylation (DNAm) might be a biological intermediary in the pathway from smoking to lung cancer. In this study, we investigated the contribution of differential blood DNAm to explain the association between smoking and lung cancer incidence. Blood DNAm was measured in 2321 Strong Heart Study (SHS) participants. Incident lung cancer was assessed as time to event diagnoses. We conducted mediation analysis, including validation with DNAm and paired gene expression data from the Framingham Heart Study (FHS). In the SHS, current versus never smoking and pack-years single-mediator models showed, respectively, 29 and 21 differentially methylated positions (DMPs) for lung cancer with statistically significant mediated effects (14 of 20 available, and five of 14 available, positions, replicated, respectively, in FHS). In FHS, replicated DMPs showed gene expression downregulation largely in trans, and were related to biological pathways in cancer. The multimediator model identified that DMPs annotated to the genes AHRR and IER3 jointly explained a substantial proportion of lung cancer. Thus, the association of smoking with lung cancer was partly explained by differences in baseline blood DNAm at few relevant sites. Experimental studies are needed to confirm the biological role of identified eQTMs and to evaluate potential implications for early detection and control of lung cancer.
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Metilação de DNA , Neoplasias Pulmonares , Humanos , Fumar/epidemiologia , Fumar Tabaco/genética , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Sequência de Bases , Epigênese GenéticaRESUMO
The increment in water pollution due to the massive development in the industrial sector is a worldwide concern due to its impact on the environment and human health. Therefore, the development of new and sustainable alternatives for water remediation is needed. In this context, aerogels present high porosity, low density, and a remarkable adsorption capacity, making them candidates for remediation applications demonstrating high efficiency in removing pollutants from the air, soil, and water. Specifically, polymer-based aerogels could be modified in their high surface area to integrate functional groups, decrease their hydrophilicity, or increase their lipophilicity, among other variations, expanding and enhancing their efficiency as adsorbents for the removal of various pollutants in water. The aerogels based on natural polymers such as cellulose, chitosan, or alginate processed by different techniques presented high adsorption capacities, efficacy in oil/water separation and dye removal, and excellent recyclability after several cycles. Although there are different reviews based on aerogels, this work gives an overview of just the natural biopolymers employed to elaborate aerogels as an eco-friendly and renewable alternative. In addition, here we show the synthesis methods and applications in water cleaning from pollutants such as dyes, oil, and pharmaceuticals, providing novel information for the future development of biopolymeric-based aerogel.
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Borderline personality disorder (BPD) is characterized by instability in relationships, mood fluctuations, and erratic behavior. This study investigates the relationship between pathological personality traits and functional disability, the status of perceived social support in BPD, as well as its mediating role in this relationship. In this cross-sectional study, 192 Spanish women (BPD group, N = 97; healthy control group, N = 95) completed, through two online platforms, a battery of tests including: the Personality Inventory for DSM-5 Brief Form (PID-5-BF), the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) and the Perceived Social Support subscale of the Quality of Life Questionnaire (QLQ). The results show that perceived social support was significantly lower in the BPD group, which also presented a significantly higher disability score than the control group. Pathological personality traits affected functionality both directly and indirectly through perceived social support, as this variable was a significant mediator in both groups. We conclude that perceived social support is impaired in BPD patients, and enhancing it as a complementary therapy to evidence-based treatments could help preserve the functionality of patients while pathological traits are regulated. This study also encourages future research to delve into the relevance of other psychosocial variables on the functionality of subjects with BPD, and the need of enhancing them in therapy.
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A new force field for 1-propanol, in the united and all atom models, has been obtained by combining two different empirical methodologies. The first was developed by scaling atom charges and Lennard-Jones parameters to fit the dielectric constant, surface tension, and density; this methodology is named three steps systematic parameterization procedure (3SSPP), as reported by Pérez de la Luz et al. (J Chem Theory Comput 14:5949-5958, 2018). The second methodology consists of moving these parameters and together with the bond distance to obtain the liquid-vapor phase diagram of the CO2 molecule as discussed by Harris and Yung (J Phys Chem 99:12021-12024, 1995). The last methodology is used to obtain the self-diffusion coefficient, which was not consider in the 3SSPP. The 3SSPP/bond methodology is the 3SSPP plus the bond distance scaling. With this new methodology, the experimental density, dielectric constant, surface tension, and self-diffusion coefficient at ambient temperature could be achieved. Furthermore, we show the temperature dependence of the aforementioned properties. The static structure factors are in accordance with the experimental spectrum. Solubility is increased to the experimental value for the united atom (UA) model after applying this methodology and for all atom (AA) scheme, the experimental solubility value is maintained. Graphical abstract The reduction in bond distance of the 1-propanol molecule does not modify the structure factor.
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The use of proteins such as human serum albumin (HSA) to form nanometric systems seems very promising since they are non-toxic, biodegradable and have no antigenic activity. This molecule is ideal to transport insoluble drugs such as melatonin (Mel), which has antiapoptotic and antioxidant properties and appears promising for the treatment of neurodegenerative eye diseases. The objective of this study was to obtain nanoparticulate systems loaded with Mel, improving the conventional desolvation method. Systems were stabilised using two different strategies: one through the use of Eudragit S100 as a cross-linking agent and the other through thermal stabilisation. The systems thus obtained (Np-HSA-Eu-Mel and Np-HSA-Mel, respectively) were characterised and compared in terms of physicochemical and pharmacotechnical parameters. Whitish colloidal dispersions of nanometric size (≈170 nm), spherical shape, and monodisperse population were obtained. Besides, the pH was close to neutrality reaching 20 % drug encapsulation whereas the process performance was higher than 80 %. In FT-IR studies, thermal analysis and X-ray diffraction (XRD), the incorporation of the drug in the cavities of the nanoparticles could be evidenced. Regarding the physical stability of nanoparticles, for Np-HSA-Eu-Mel instability was observed at pH > 7. However, Np-HSA-Mel was able to remain stable at different pH levels. Mel release from these systems was consequently affected, where the former released faster than the active compared to the last. On the other hand, it was observed that the drying process (lyophilization in this case) applied to the nanoparticles suspensions does not affect their original properties after redispersion over a three months period. Likewise, the formulation did not produce irritation when administered topically, whereas when administered subconjunctivally, only slight irritation was observed 24 h after administration. According to the result of this study, the Np-HSA-Mel formulation could achieve advantageous properties as a vehicle for the transport of insoluble drugs for the treatment of neurodegenerative diseases at the ocular level.
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Melatonina , Nanopartículas , Humanos , Albumina Sérica Humana/química , Administração Oftálmica , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química , Portadores de Fármacos/química , Tamanho da PartículaRESUMO
Background: To assess whether expectant observation of infants ≤ 90 days old with small suprarenal masses (sSRMs) could avoid unnecessary surgery without impacting outcome. Methods: Infants ≤ 90 days with a ≤ 5 cm mass, without midline extension or lymph node or distant spread were registered (ClinicalTrials.org:NCT01728155). Once staging was completed, they were followed with ultrasound, MRI and urinary catecholamines. Surgical resection was only planned if there was a ≥40% mass volume increase or for a mass persisting after 48 weeks of the planned observation. Results: Over a 5-year period, 128 infants were registered. No infant had detectable MYCN amplification in the peripheral blood. Surgery was performed in 39 (30.5%) patients, in 18 during and in 21 after the planned 48-week observation, and 74% were confirmed to be neuroblastomas. Non-life-threatening surgical complications occurred in two cases. The 3-year overall survival and event-free survival were 100% and 87.1%, respectively. The 16 events observed were volume increase (N = 11) and progression to neuroblastoma stage MS (N = 5). Patients with solid masses or MIBG-positive masses had lower EFS. Conclusions: Expectant observation for infants with sSRMs with clinical follow-up and timely imaging (including MRI scan) is safe and effective, allowing surgery to be avoided in the majority of them.