PM2.5, component cause of severe metabolically abnormal obesity: An in silico, observational and analytical study.

Obesity is currently one of the most alarming pathological conditions due to the progressive increase in its prevalence. In the last decade, it has been associated with fine particulate matter suspended in the air (PM2.5). The purpose of this study was to explore the mechanistic interaction of PM2.5 with a high-fat diet (HFD) through the differential regulation of transcriptional signatures, aiming to identify the association of these particles with metabolically abnormal obesity. The research design was observational, using bioinformatic methods and an explanatory approach based on Rothman's causal model. We propose three new transcriptional signatures in murine adipose tissue. The sum of transcriptional differences between the group exposed to an HFD and PM2.5, compared to the control group, were 0.851, 0.265, and -0.047 (p > 0.05). The HFD group increased body mass by 20% with two positive biomarkers of metabolic impact. The group exposed to PM2.5 maintained a similar weight to the control group but exhibited three positive biomarkers. Enriched biological pathways (p < 0.05) included PPAR signaling, small molecule transport, adipogenesis genes, cytokine-cytokine receptor interaction, and HIF-1 signaling. Transcriptional regulation predictions revealed CpG islands and common transcription factors. We propose three new transcriptional signatures: FAT-PM2.5-CEJUS, FAT-PM2.5-UP, and FAT-PM2.5-DN, whose transcriptional regulation profile in adipocytes was statistically similar by dietary intake and HFD and exposure to PM2.5 in mice; suggesting a mechanistic interaction between both factors. However, HFD-exposed murines developed moderate metabolically abnormal obesity, and PM2.5-exposed murines developed severe abnormal metabolism without obesity. Therefore, in Rothman's terms, it is concluded that HFD is a sufficient cause of the development of obesity, and PM2.5 is a component cause of severe abnormal metabolism of obesity. These signatures would be integrated into a systemic biological process that would induce transcriptional regulation in trans, activating obesogenic biological pathways, restricting lipid mobilization pathways, decreasing adaptive thermogenesis and angiogenesis, and altering vascular tone thus inducing a severe metabolically abnormal obesity.

[Translated article] The role of minimally invasive spine surgery in the treatment of vertebral metastasis: A narrative review.

BACKGROUND: Spinal metastases are a very common problem which dramatically affects the quality of life of cancer patients. The objective of this review is to address the issue of how minimally invasive surgery can play an important role in treating this pathology. METHODS: A literature review was performed, searching in the Google Scholar, PubMed, Scopus and Cochrane databases. Relevant and quality papers published within the last 10 years were included in the review. RESULTS: After screening the 2184 initially identified registers, a total of 24 articles were included for review. CONCLUSION: Minimally invasive spine surgery is specially convenient for fragile cancer patients with spinal metastases, because of its reduced comorbidity compared to conventional open surgery. Technological advances in surgery, such as navigation and robotics, improve accuracy and safety in this technique.

The role of minimally invasive spine surgery in the treatment of vertebral metastasis: A narrative review. / El papel de la cirugía mínimamente invasiva de columna en el tratamiento de las metástasis vertebrales: una revisión narrativa.

BACKGROUND: Spinal metastases are a very common problem which dramatically affects the quality of life of cancer patients. The objective of this review is to address the issue of how minimally invasive surgery can play an important role in treating this pathology. METHODS: A literature review was performed, searching in the Google Scholar, PubMed, Scopus and Cochrane databases. Relevant and quality papers published within the last 10 years were included in the review. RESULTS: After screening the 2184 initially identified registers, a total of 24 articles were included for review. CONCLUSION: Minimally invasive spine surgery is specially convenient for fragile cancer patients with spinal metastases, because of its reduced comorbidity compared to conventional open surgery. Technological advances in surgery, such as navigation and robotics, improve accuracy and safety in this technique.

The role of minimally invasive spine surgery in the treatment of vertebral metastasis (part 1): A clinical review. / El papel de la cirugía mínimamente invasiva de columna en el tratamiento de las metástasis vertebrales (parte 1): una revisión clínica.

Spinal metastases represent a significant burden on the quality of life in patients affected by active oncological disease due to the high incidence of pain syndromes, spinal deformity, and neurological impairment. Surgery plays a decisive role in improving quality of life by controlling pain, restoring neurological function and maintaining spinal stability, as well as contributing to the response to medical therapy. Minimally invasive surgery (MIS) is a treatment option in certain patients with high surgical risk since it has a low rate of complications, intraoperative bleeding, hospital stay, and offers similar results to open surgery. In this review, we present the role of MIS in this pathology and some cases treated in our hospital.

[Translated article] The role of minimally invasive spine surgery in the treatment of vertebral metastasis (Part 1): A clinical review.

Spinal metastases represent a significant burden on the quality of life in patients affected by active oncological disease due to the high incidence of pain syndromes, spinal deformity, and neurological impairment. Surgery plays a decisive role in improving quality of life by controlling pain, restoring neurological function and maintaining spinal stability, as well as contributing to the response to medical therapy. Minimally invasive surgery (MIS) is a treatment option in certain patients with high surgical risk since it has a low rate of complications, intraoperative bleeding, hospital stay, and offers similar results to open surgery. In this review, we present the role of MIS in this pathology and some cases treated in our hospital.

Time-Dependent Mechanical Properties in Polyetherimide 3D-Printed Parts Are Dictated by Isotropic Performance Being Accurately Predicted by the Generalized Time Hardening Model.

The Fused-Deposition Modelling (FDM) technique has transformed the manufacturing discipline by simplifying operational processes and costs associated with conventional technologies, with polymeric materials being indispensable for the development of this technology. A lack of quantification of viscoelastic/plastic behavior has been noted when addressing FDM parts with Polyetherimide (PEI), which is currently being investigated as a potential material to produce functional end-products for the aerospace and health industry. Primary and secondary creep along with stress relaxation tests have been conducted on FDM PEI specimens by applying stresses from 10 to 40 MPa for 100 to 1000 min. Specimens were 3D printed by varying the part build orientation, namely XY, YZ, and XZ. Creep results were fitted to the Generalized Time Hardening equation (GTH), and then this model was used to predict stress relaxation behavior. FDM PEI parts presented an isotropic creep and stress relaxation performance. The GTH model was proven to have a significant capacity to fit viscoelastic/plastic performances for each single build orientation (r > 0.907, p < 0.001), as well as a tight prediction of the stress relaxation behavior (r > 0.998, p < 0.001). Averaged-orientation coefficients for GTH were also closely correlated with experimental creep data (r > 0.958, p < 0.001) and relaxation results data (r > 0.999, p < 0.001). FDM PEI parts showed an isotropic time-dependent behavior, which contrasts with previous publications arguing the significant effect of part build orientation on the mechanical properties of FDM parts. These findings are strengthened by the high correlation obtained between the experimental data and the averaged-coefficient GTH model, which has been proven to be a reliable tool to predict time-dependent performance in FDM parts.

Arterial pulse attenuation prediction using the decaying rate of a pressure wave in a viscoelastic material model.

The present study examines the possibility of attenuating blood pulses by means of introducing prosthetic viscoelastic materials able to absorb energy and damp such pulses. Vascular prostheses made of polymeric materials modify the mechanical properties of blood vessels. The effect of these materials on the blood pulse propagation remains to be fully understood. Several materials for medical applications, such as medical polydimethylsiloxane or polytetrafluoroethylene, show viscoelastic behavior, modifying the original vessel stiffness and affecting the propagation of blood pulses. This study focuses on the propagation of pressure waves along a pipe with viscoelastic materials using the Maxwell and the Zener models. An expression of exponential decay has been obtained for the Maxwell material model and also for low viscous coefficient values in the Zener model. For relatively high values of the viscous term in the Zener model, the steepest part of the pulse can be damped quickly, leaving a smooth, slowly decaying wave. These mathematical models are critical to tailor those materials used in cardiovascular implants to the mechanical environment they are confronted with to repair or improve blood vessel function.

Organochlorine pesticides in placentas from Southern Spain and some related factors.

During pregnancy, lipophilic xenobiotics stored in maternal adipose tissue can be mobilized and enter her blood circulation and reach the placenta. This study measured residues of oestrogen-mimicking organochlorine pesticides (OCs) in 150 placenta samples from women in Southern Spain. OCs were extracted from placenta by solid-liquid technique and purified by preparative liquid chromatography. Gas chromatography/electron-capture detection and mass spectrometry were used to identify and quantify p,p'-DDT and congeners/metabolites, endosulphan and congeners/metabolites, lindane, aldrin/dieldrin/endrin, hexachlorobenzene, methoxychlor and mirex. A mean of eight pesticides per placenta were detected (range, 3-15 pesticides). Endosulphan-ether, endosulphan-diol, endosulphan-I, p,p'-DDE, o,p'-DDD, p,p'-DDT, o,p'-DDT and lindane were detected in >or=50% of samples; p,p'-DDE was the most frequent (96.03%), followed by endosulphan-diol (76.86%) and lindane (74.17%). Presence of more pesticides was significantly associated with lower birth weight. Mean concentration of p,p'-DDE was 2.37+/-2.80 ng/g of placenta or 76.62+/-104.85 ng/g of lipid. Higher maternal body mass index was significantly associated with higher endosulphan concentrations in placenta, and greater maternal weight gain was significantly associated with higher p,p'-DDE concentrations. Prenatal exposure to OC xenoestrogens may be a causative factor in adverse reproductive health trends, and further studies are required to identify and describe pathways of this exposure to enhance preventive measures.

Genetic redundancy strengthens the circadian clock leading to a narrow entrainment range.

Circadian clocks are internal timekeepers present in almost all organisms. Driven by a genetic network of highly conserved structure, they generate self-sustained oscillations that entrain to periodic external signals such as the 24 h light-dark cycle. Vertebrates possess multiple, functionally overlapping homologues of the core clock genes. Furthermore, vertebrate clocks entrain to a range of periods three times as narrow as that of other organisms. We asked whether genetic redundancies play a role in governing entrainment properties and analysed locomotor activity rhythms of genetically modified mice lacking one set of clock homologues. Exposing them to non-24 h light-dark cycles, we found that the mutant mice have a wider entrainment range than the wild types. Spectral analysis furthermore revealed nonlinear phenomena of periodically forced self-sustained oscillators for which the entrainment range relates inversely to oscillator amplitude. Using the forced oscillator model to explain the observed differences in entrainment range between mutant and wild-type mice, we sought to quantify the overall oscillator amplitude of their clocks from the activity rhythms and found that mutant mice have weaker circadian clocks than wild types. Our results suggest that genetic redundancy strengthens the circadian clock leading to a narrow entrainment range in vertebrates.

Discurso narrativo en preescolares con trastorno específico del lenguaje y con desarrollo típico / Narrative discourse in preschool children with specific language impairment and typically developing children

En esta investigación se realizó un análisis de la producción y comprensión del discurso en preescolares de la comuna de Talca, Séptima región de Chile. El objetivo fue comparar el desempeño en la producción y comprensión del discurso narrativo de pre escolares con Trastorno Específico de Lenguaje con el desempeño de preescolares que presentan desarrollo típico. Para ello, se evaluó a niñas y niños que se encontraban cursando primer nivel de transición en una escuela de lenguaje y párvulos de la comuna de Talca. Este estudio presenta un enfoque cuantitativo con un diseño descriptivo - explicativo. La muestra contó con 40 estudiantes, 20 con Trastorno específico del lenguaje y 20 con desarrollo típico. Al comparar ambos grupos, los resultados indican que no se apreciandiferencias significativas en la producción narrativa entre ambos grupos de niños, sin embargo, sí se presentan diferencias significativas en la comprensión del discurso, a favor de los niños con desarrollo típico de lenguaje

This study considered the analysis of the production and comprehension of narrative discourse by a group of preschool children in Talca, Chile. The main objective was to compare the production and comprehension of narrative discourse by preschool children with SLI and typically developing children. All children were assessed on both skills. The study adopted a descriptive-comparative design. The sample comprised 40 children: 20 children with SLI and 20 with TLD. After comparing both groups, results showed no significant differences on narrative discourse production. However, significant differences were found in narrative comprehension: children with TLD performed higher than children with SLI

Organochlorine pesticides in umbilical cord blood serum of women from Southern Spain and adherence to the Mediterranean diet.

Exposure of pregnant women to organochlorine (OC) pesticides largely derives from contaminated food, but environmental, occupational, and domestic factors have also been implicated. We investigated the presence of nine OC residues in the umbilical cord blood of newborns in Southern Spain and analyzed the relationship of this exposure with maternal and pregnancy variables, including maternal adherence to the Mediterranean Diet (MD). OCs were detected in 95% of umbilical cord blood samples from the 318 mothers, who had a mean degree of adherence to the MD of 56.77 (SD: 16.35) (range, 0-100). The MD prioritizes consumption of vegetable and fruit over meat and dairy products, and OCs are generally lipophilic molecules that accumulate in foods of animal origin. Consumption of meat, fish, and dairy products was associated with dichlorodiphenyldichloroethylene (DDE) in umbilical cord serum, and dairy product intake with lindane. Vegetable consumption was also associated with lindane and fruit intake with endosulfan I. We found no significant association between MD adherence and the presence of OC residues in serum. However, closer adherence to the MD may offer greater protection against OC exposure because of its reduced content in meat and dairy products.

Phase response curves elucidating the dynamics of coupled oscillators.

Phase response curves (PRCs) are widely used in circadian clocks, neuroscience, and heart physiology. They quantify the response of an oscillator to pulse-like perturbations. Phase response curves provide valuable information on the properties of oscillators and their synchronization. This chapter discusses biological self-sustained oscillators (circadian clock, physiological rhythms, etc.) in the context of nonlinear dynamics theory. Coupled oscillators can synchronize with different frequency ratios, can generate toroidal dynamics (superposition of independent frequencies), and may lead to deterministic chaos. These nonlinear phenomena can be analyzed with the aid of a phase transition curve, which is intimately related to the phase response curve. For illustration purposes, this chapter discusses a model of circadian oscillations based on a delayed negative feedback. In a second part, the chapter provides a step-by-step recipe to measure phase response curves. It discusses specifications of this recipe for circadian rhythms, heart rhythms, neuronal spikes, central pattern generators, and insect communication. Finally, it stresses the predictive power of measured phase response curves. PRCs can be used to quantify the coupling strength of oscillations, to classify oscillator types, and to predict the complex dynamics of periodically driven oscillations.

Dietary exposure assessment of pregnant women to bisphenol-A from cans and microwave containers in Southern Spain.

Bisphenol-A (BPA), material for polycarbonate and epoxy resin synthesis, has been detected in canned food, among other food containers. In mammal studies, BPA transferred from mother to fetus, caused abnormality of reproductive organs, and advanced female puberty. BPA from canned food and microwave containers was analyzed using high performance liquid chromatography and gas chromatography-mass spectrometry. Population was cohort of mother-son pairs established at Granada University Hospital. Frequency of food consumption (including canned food) was studied with a semi-quantitative questionnaire. The most frequently consumed products were fish and juice cans, consumed 1-3 times/week by 34.7% and 22.3% of the study population, respectively. The women made little use of polymer microwave containers, 52.8% never using them and 45.9% using them <3 times/month. Estimated mean (standard deviation) intake of BPA was 1.1(0.839) microgram/day. No relationship was found between BPA exposure and maternal socio-demographic variables or newborn characteristics. This study offers the first estimate of BPA dietary intake by pregnant women in Southern Spain. The consumption of canned foods and drinks by these women means that their exposure was lower than EFSA estimates for the European population. Nevertheless it remains of concern, given the proven undesirable effects of low-level exposure and higher susceptibility of pregnant women.

Oestrogenicity of paper and cardboard extracts used as food containers.

Bisphenol-A (BPA), dibutyl phthalate (DBP), and di-2-ethylhexyl phthalate (DEHP), which are common chemical residues in food-packaging materials, were investigated in paper and cardboard containers used for take-away food. The oestrogenicity of aqueous extracts was tested in E-Screen bioassay and analysis carried out by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC/MS). Oestrogenicity was demonstrated in 90% of extracts (geometric mean [GM] = 11.97 pM oestradiol equivalents g(-1)). DEHP, DBP, and BPA (GM = 341.74, 37.59, and 2.38 ng g(-1) of material) were present in 77.50, 67.50, and 47.50% of samples, respectively. In bivariate analyses, no significant association was found between the levels of these chemicals and oestrogenicity in cardboard/paper extracts. A close-to-significant association was found between oestrogenicity and DBP (beta = 1.25; p = 0.06) in paper extracts, which reached statistical significance in multivariate analysis (beta = 1.61; p = 0.03). Paper and cardboard used in food packaging may contribute to the inadvertent exposure of consumers to endocrine-disrupting chemicals.

O emprego de sistemas de liberação como estratégia para melhorar as propriedades terapêuticas de fármacos de origem natural: o exemplo da camptotecina e seus derivados / Drug delivery systems as a way to improve the therapeutic properties of natural drugs: the example of camptothecin and its derivatives

As plantas têm sido utilizadas para a obtenção de um grande número de substâncias biologicamente ativas. Entretanto, muitos compostos naturais quando empregados sem qualquer modificação química não resultaram em medicamentos eficazes, por não apresentarem as características desejáveis para administração. Neste sentido, a melhoria das propriedades terapêuticas de compostos isolados de plantas por meio da sua incorporação em sistemas de liberação de fármacos consiste em uma importante estratégia na obtenção de novos medicamentos, na qual ainda existe muito a ser explorado. Tais sistemas são caracterizados por apresentar a capacidade de prolongar e controlar a liberação de substâncias ativas, proteger as moléculas frente à degradação no meio biológico, veicular fármacos hidrofóbicos e reduzir os efeitos colaterais indesejáveis. A camptotecina, um alcalóide proveniente do arbusto Camptotheca acuminata (Descaisne, Nyssaceae), é um fármaco que apresenta elevada atividade antitumoral, cujo mecanismo envolve a inibição da topoisomerase I, uma enzima altamente expressa nos tumores. Entretanto, a utilização deste fármaco na terapêutica foi limitada, durante anos, em virtude de suas características de baixa solubilidade aquosa, elevada instabilidade em meio fisiológico e elevada toxicidade. Neste artigo é realizada uma revisão sobre o potencial terapêutico da camptotecinae seus análogos no tratamento do câncer, dando ênfase aos estudos conduzidos com o intuito de contornar as limitações da administração destes fármacos e que resultaram na melhoria das propriedades terapêuticas. Estratégias como a microencapsulação, nanoencapsulação e solubilização em micelas poliméricas, entre outras, são discutidas e os principais resultados de atividade antitumoral in vitro e in vivo são apresentados.