Epoxide of diosgenin acetate synthesis: DoE for diastereoselective yield optimization, antimicroibial, antioxidant and antiproliferative effects.

Diosgenin and its derivatives have proved a huge importance in diverse biological activities. The optimized production of the diastereoisomers of the epoxide of diosgenin acetate by means of mCPBA is reported herein. This transformation had a previous design of experiments using the application of a statistical factorial DoE of 4 parameters (nk), where one variable is varied at a time, while others stay constant. The temperature showed the greatest effect on the reaction yield; so, at 298 K the diastereomeric ratio 3:1 of α and ß-epoxides, normally found, was raised to 1:1. Time was the second significant variable, but due to its high correlation with temperature, 30 min were required for a global 90% conversion at least. These diastereoisomers were characterized both isolated and in the mixtures obtained, to determine their antioxidant, antimicrobial and antiproliferative activity, finding a low antioxidant capacity by DPPH, but antimicrobial activity at the level of penicillin in gram negative bacteria by 1ß better to 1α. The antiproliferative capacity was higher for diastereoisomer ß, agreeing with the proportion of the mixture obtained by different conditions, increasing this in relation to the amount of this diastereoisomer present in hormone-dependent cancer cell lines such as Hela, PC-3 and MCF-7, with 10.0 µM obtained values of viability at 21.8 %, 35.8 % and 12.3 % respectively. DoE optimization allows to manipulate the ratio between diastereoisomers with the minimum number of experiments, extending the analysis of the effect of the ratio between diastereoisomers and the in silico potential as well as the biological activity.

Impacto de la rehabilitación pulmonar en pacientes con enfermedad pulmonar restrictiva / Impact of pulmonary rehabilitation in patients with restrictive pulmonary disease

Introducción: Las enfermedades pulmonares restrictivas presentan alteraciones en la mecánica toracopulmonar, reducción de la capacidad funcional y de la función pulmonar. Se pueden encontrar las alteraciones intrínsecas y extrínsecas donde se ven alterados el intersticio, la expansibilidad torácica e incluso afecciones del parénquima pulmonar. La rehabilitación pulmonar podría beneficiar a pacientes con la condición restrictiva y mejorar su condición funcional. Objetivo Establecer el impacto de la rehabilitación pulmonar en pacientes con compromiso respiratorio restrictivo intrínseco y extrínseco en la disnea, capacidad funcional, ansiedad/depresión y calidad de vida relacionada con la salud. Métodos Estudio descriptivo longitudinal con 50 pacientes con enfermedad pulmonar restrictiva y quienes realizaron rehabilitación pulmonar en una clínica de la ciudad de Cali, Colombia. Los participantes vinculados al estudio fueron separados en dos grupos: el primero con enfermedad restrictiva intrapulmonar (ERI) y el segundo grupo con enfermedad restrictiva extrapulmonar (ERE). Resultados La edad media de los pacientes fue de 53,3años. Entre las enfermedades restrictivas intrapulmonares se presentaron: enfermedad intersticial pulmonar difusa (EPID), postcondición de neumonías o síndrome de dificultad respiratoria aguda (SDRA) y secuelas de tuberculosis pulmonar. Y entre las enfermedades respiratorias extrapulmonares: resección pulmonar, resección de lóbulo pulmonar y resección en cuña. Al finalizar la rehabilitación pulmonar el grupo ERI presentó mejorías estadísticamente significativas en la distancia recorrida, consumo de oxígeno estimado (VO2e), disnea, ansiedad y calidad de vida. El grupo ERE presentó incremento significativo en la distancia recorrida y VO2e (AU)

Introduction: Restrictive lung diseases present alterations in thoracic-pulmonary mechanics, reduced functional capacity and lung function. Intrinsic and extrinsic alterations can be found where the interstitium, thoracic expandability and even lung parenchymal conditions are altered. Pulmonary rehabilitation could benefit patients with the restrictive condition and improve their functional condition. Objective Establish the impact of pulmonary rehabilitation in patients with intrinsic and extrinsic restrictive respiratory compromise on dyspnea, functional capacity, anxiety/depression and health-related quality of life. Methods Longitudinal descriptive study with 50 patients with restrictive lung disease who performed pulmonary rehabilitation in a clinic in the city of Cali, Colombia. The participants linked to the study were separated into two groups, the first with intrapulmonary restrictive disease (IRD) and the second group with extrapulmonary restrictive disease (ERD). Results The mean age of the patients was 53.3years. Among the restrictive intrapulmonary diseases there were: diffuse interstitial lung disease (ILD), post-condition pneumonia and/or acute respiratory distress syndrome (ARDS) and sequelae of pulmonary tuberculosis. Extrapulmonary respiratory diseases: lung resection, pulmonary lobe resection, and wedge resection. At the end of pulmonary rehabilitation, the IRD group presented statistically significant improvements in distance covered, estimated oxygen consumption (VO2e), dyspnea, anxiety, and quality of life. The ERD group presented a significant increase in the distance traveled and VO2e. Conclusion Patients with restrictive lung disease improve the distance traveled, VO2e, dyspnea, anxiety and quality of life; patients with extrapulmonary respiratory disease show improvements in functional capacity (AU)

Decay and renormalization of a longitudinal mode in a quasi-two-dimensional antiferromagnet.

An ongoing challenge in the study of quantum materials, is to reveal and explain collective quantum effects in spin systems where interactions between different modes types are important. Here we approach this problem through a combined experimental and theoretical study of interacting transverse and longitudinal modes in an easy-plane quantum magnet near a continuous quantum phase transition. Our inelastic neutron scattering measurements of Ba2FeSi2O7 reveal the emergence, decay, and renormalization of a longitudinal mode throughout the Brillouin zone. The decay of the longitudinal mode is particularly pronounced at the zone center. To account for the many-body effects of the interacting low-energy modes in anisotropic magnets, we generalize the standard spin-wave theory. The measured mode decay and renormalization is reproduced by including all one-loop corrections. The theoretical framework developed here is broadly applicable to quantum magnets with more than one type of low energy mode.

Magnetic properties of the Ising-like rare earth pyrosilicate: D-Er2Si2O7.

Ising-like spin-1/2 magnetic materials are of interest for their ready connection to theory, particularly in the context of quantum critical behavior. In this work we report detailed studies of the magnetic properties of a member of the rare earth pyrosilicate family, D-Er2Si2O7, which is known to display a highly anisotropic Ising-likeg-tensor and effective spin-1/2 magnetic moments. We used powder neutron diffraction, powder inelastic neutron spectroscopy (INS), and single crystal AC susceptibility to characterize its magnetic properties. Neutron diffraction enabled us to determine the magnetic structure below the known transition temperature (TN= 1.9 K) in zero field, confirming that the magnetic state is a four-sublattice antiferromagnetic structure with two non-collinear Ising axes, as was previously hypothesized. Our powder INS data revealed a gapped excitation at zero field, consistent with anisotropic (possibly Ising) exchange. An applied field of 1 T produces a mode softening, which is consistent with a field-induced second order phase transition. To assess the relevance of D-Er2Si2O7to the transverse field Ising model, we performed AC susceptibility measurements on a single crystal with the magnetic field oriented in the direction transverse to the Ising axes. This revealed a transition at 2.65 T at 0.1 K, a field significantly higher than the mode-softening field observed by powder INS, showing that the field-induced phase transitions are highly field-direction dependent as expected. These measurements suggest that D-Er2Si2O7may be a candidate for further exploration related to the transverse field Ising model.

From One- to Two-Magnon Excitations in the S=3/2 Magnet ß-CaCr_{2}O_{4}.

We apply neutron spectroscopy to measure the magnetic dynamics in the S=3/2 magnet ß-CaCr_{2}O_{4} (T_{N}=21 K). The low-energy fluctuations, in the ordered state, resemble large-S linear spin waves from the incommensurate ground state. However, at higher energy transfers, these semiclassical and harmonic dynamics are replaced by an energy and momentum broadened continuum of excitations. Applying kinematic constraints required for energy and momentum conservation, sum rules of neutron scattering, and comparison against exact diagonalization calculations, we show that the dynamics at high-energy transfers resemble low-S one-dimensional quantum fluctuations. ß-CaCr_{2}O_{4} represents an example of a magnet at the border between classical Néel and quantum phases, displaying dual characteristics.

Intertwined density waves in a metallic nickelate.

Nickelates are a rich class of materials, ranging from insulating magnets to superconductors. But for stoichiometric materials, insulating behavior is the norm, as for most late transition metal oxides. Notable exceptions are the 3D perovskite LaNiO3, an unconventional paramagnetic metal, and the layered Ruddlesden-Popper phases R4Ni3O10, (R = La, Pr, Nd). The latter are particularly intriguing because they exhibit an unusual metal-to-metal transition. Here, we demonstrate that this transition results from an incommensurate density wave with both charge and magnetic character that lies closer in its behavior to the metallic density wave seen in chromium metal than the insulating stripes typically found in single-layer nickelates like La2-xSrxNiO4. We identify these intertwined density waves as being Fermi surface-driven, revealing a novel ordering mechanism in this nickelate that reflects a coupling among charge, spin, and lattice degrees of freedom that differs not only from the single-layer materials, but from the 3D perovskites as well.

Overweight and obesity status from the prenatal period to adolescence and its association with non-alcoholic fatty liver disease in young adults: cohort study.

OBJECTIVE: To examine the associations of maternal and child overweight status across multiple time-points with liver fat content in the offspring during young adulthood. DESIGN: Cohort study. SETTING: ELEMENT Cohort in Mexico City. POPULATION: Pregnant women with singleton births (n = 97). METHODS: We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2-weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log-transformed) in young adulthood. MAIN OUTCOME: Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood. RESULTS: Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (ß = 1.97, 95% CI 1.28-3.05), and OWOB status in the offspring at young adulthood (ß = 3.17, 95% CI 2.10-4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status. CONCLUSION: We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring. TWEETABLE ABSTRACT: There was an association between pre-pregnancy overweight and the development of NAFLD in adult offspring.

Low-energy magnons in the chiral ferrimagnet Cu2OSeO3: A coarse-grained approach.

We report a comprehensive neutron scattering study of low energy magnetic excitations in the breathing pyrochlore helimagnetic Cu2OSeO3. Fully documenting the four lowest energy magnetic modes that leave the ferrimagnetic configuration of the "strong tetrahedra" intact ( | ℏ ω | < 13 meV), we find gapless quadratic dispersion at the point for energies above 0.2 meV, two doublets separated by 1.6(2) meV at the R point, and a bounded continuum at the X point. Our constrained rigid spin cluster model relates these features to Dzyaloshinskii-Moriya (DM) interactions and the incommensurate helical ground state. Combining conventional spin wave theory with a spin cluster form factor accurately reproduces the measured equal time structure factor through multiple Brillouin zones. An effective spin Hamiltonian describing complex anisotropic intercluster interactions is obtained.

Anharmonic Magnon Excitations in Noncollinear and Charge-Ordered RbFe

RbFe^{2+}Fe^{3+}F_{6} is an example of a charge ordered antiferromagnet where iron sites, with differing valences, are structurally separated into two interpenetrating sublattices. The low temperature magnetically ordered Fe^{2+} (S=2) and Fe^{3+} (S=5/2) moments form a noncollinear orthogonal structure with the Fe^{3+} site displaying a reduced static ordered moment. Neutron spectroscopy on single crystals finds two distinct spin wave branches with a dominant coupling along the Fe^{3+} chain axis (b axis). High resolution spectroscopic measurements find an intense energy and momentum broadened magnetic band of scattering bracketing a momentum-energy region where two magnon processes are kinematically allowed. These anharmonic excitations are enhanced in this noncollinear magnet owing to the orthogonal spin arrangement.

From Ising Resonant Fluctuations to Static Uniaxial Order in Antiferromagnetic and Weakly Superconducting CeCo(In_{1-x}Hg_{x})_{5}(x=0.01).

CeCo(In_{0.990}Hg_{0.010})_{5} is a charge doped variant of the d-wave CoCoIn_{5} superconductor with coexistent antiferromagnetic and superconducting transitions occurring at T_{N}=3.4 and T_{c}=1.4 K, respectively. We use neutron diffraction and spectroscopy to show that the magnetic resonant fluctuations present in the parent superconducting phase are replaced by collinear c-axis magnetic order with three-dimensional Ising critical fluctuations. No low-energy transverse spin fluctuations are observable in this doping-induced antiferromagnetic phase and the dynamic resonant spectral weight predominately shifts to the elastic channel. Static (τ>0.2 ns) collinear Ising order is proximate to superconductivity in CeCoIn_{5} and is stabilized through hole doping with Hg.

Local quantum phase transition in YFe2Al10.

A phase transition occurs when correlated regions of a new phase grow to span the system and the fluctuations within the correlated regions become long lived. Here, we present neutron scattering measurements showing that this conventional picture must be replaced in YFe2Al10, a compound that forms naturally very close to a [Formula: see text] quantum phase transition. Fully quantum mechanical fluctuations of localized moments are found to diverge at low energies and temperatures; however, the fluctuating moments are entirely without spatial correlations. Zero temperature order in YFe2Al10 is achieved by an entirely local type of quantum phase transition that may originate with the creation of the moments themselves.

Expanding indication of padeliporfin (WST11) vascular-targeted photodynamic therapy: results of prostate cancer Latin-American multicenter study. / Extensión de la indicación de terapia fotodinámica dirigida vascular con padeliporfina (WST11): resultados de un estudio multicéntrico latinoamericano del cáncer de próstata.

OBJECTIVES: To explore the proportion of patients with higher risk localized prostate cancer (PCa) that would become safely biopsy negative 12 months after non-thermal focal therapy with padeliporfin vascular-targeted photodynamic therapy (VTP). METHODS: Multicenter study in a scenario of prostate-specific antigen (PSA) ≤20ng/ml and variable PCa target volumes Gleason pattern 3 or low-volume secondary Gleason pattern 4, all patients received VTP, consisting of intravenous 4mg/kg padeliporfin activated by light-diffusing fibers in the prostate. The prostate was biopsied at baseline, months 6 and 12, PSA, patient-reported functional outcomes and quality of life (QoL) questionnaires were recorded at baseline, months 3, 6, and 12 and adverse events (AE) throughout the study. RESULTS: In the intention-to-treat population (n=81), the proportion of patients with negative biopsies at month 12 was 74% (60/81 patients; 95% CI: 63.1%,83.2%). In the per-protocol population, the proportion was 79% (58/73 patients; 95% CI: 68.4%,88.0%). Questionnaire results indicated a slight improvement in urinary function and limited deterioration in sexual function. No difference in QoL was observed over time. A total of 42/81 (52%) patients reported mild or moderate and 4 of 81 (4.9%) experienced serious AE, all resolved without sequelae. No phototoxicity, cardiovascular event, fistula or prolonged urinary incontinence, secondary cancer or death was reported. CONCLUSIONS: Results support the efficacy, safety, and QoL associated with padeliporfin focal treatment for low/intermediate risk localized PCa.

Screened moments and extrinsic in-gap states in samarium hexaboride.

Samarium hexaboride (SmB6) is a Kondo insulator, with a narrow gap due to hybridization between localized and conduction electrons. Despite being an insulator, many samples show metal-like properties. Rare-earth purification is exceedingly difficult, and nominally pure samples may contain 2% or more of impurities. Here to determine the effects of rare-earth doping on SmB6, we synthesized and probed a series of gadolinium-doped samples. We found a relationship between specific heat and impurity moment screening which scales systematically. Consistent with this finding, our neutron scattering experiments of a high purity sample of doubly isotopic 154Sm11B6 show no intrinsic excitations below the well-established 13 meV spin-exciton. The result of introducing impurities into a Kondo insulator is incompletely understood, but it is clear from our measurements that there is a systematic relationship between rare-earth impurities and metal-like properties in SmB6.

Dysphagia secondary to focal inflammatory myopathy and consequent dorsiflexion of the tongue in a dog.

A 14-month-old female pitbull terrier mix was presented for evaluation of dysphagia of 8 months' duration secondary to intermittent dorsiflexion of the tongue apex. Physical and neurological examinations were unremarkable with the exception of the dorsiflexed tongue. Serum creatine kinase activity was increased (703 IU/L, reference interval: 55 to 257 IU/L), and electromyography of the tongue demonstrated areas of fibrillation potentials. Histopathology of the tongue showed myopathic changes with excessive variability in myofibre size and endomysial fibrosis. Cytochemical stains verified mixed mononuclear cells throughout the endomysium and perimysium consistent with a chronic inflammatory myopathy. No improvement was reported following prednisone administration; although the dog was able to prehend kibble, it needed assistance when drinking water. This is the first report documenting a focal lingual myopathy in a non-corgi breed and highlights the utility of determining creatine kinase activity and obtaining tongue biopsies when warranted in dysphagic animals.

Prevention of childhood obesity and food policies in Latin America: from research to practice.

BACKGROUND: Addressing childhood obesity in Latin America requires a package of multisectoral, evidence-based policies that enable environments conducive to healthy lifestyles. OBJECTIVE: Identify and examine key elements to translating research into effective obesity policies in Latin America. METHODS: We examined obesity prevention policies through case studies developed with an expert in the specific policy. Policies were selected based on their level of implementation, visibility and potential impact to reduce childhood obesity. They include: (i) excise taxes on sugar sweetened beverages and energy-dense foods; (ii) front-of-package food label legislation; (iii) trans fatty acids removal from processed foods; and (iv) Ciclovías recreativas or 'open streets'. Case studies were coded to identify components that explained successful implementation and sustainability using the Complex Adaptive Health Systems framework. RESULTS: The analysis identified key elements for effective and sustainable policy, including evidence justifying policy; evidence-based advocacy by civil society; political will; and legislation and skillful negotiations across government, academia, the private sector and civil society. Scientific evidence and evaluation played an important role in achieving tipping points for policies' launch and sustain effective implementation. CONCLUSIONS: Well-coordinated, intersectoral partnerships are needed to successfully implement evidence-based anti-obesity policies. Prospective policy research may be useful for advancing knowledge translation.

Preventing childhood obesity in Latin America: an agenda for regional research and strategic partnerships.

The increasing prevalence of childhood obesity in Latin America poses a major public health challenge to the region. In response, many countries are implementing obesity prevention programmes aimed at modifying known risk factors. However, the limited scientific evidence inhibits the development and implementation of novel, effective interventions across the region. To address these gaps, the NIH Fogarty International Center convened a workshop of researchers, policymakers, programme implementers and public health advocates who are actively engaged in the region to prevent childhood obesity. Major aims of the meeting were to define the current status of childhood obesity, identify the scientific gaps in our understanding of the epidemic, point out the barriers and opportunities for research and outline a plan for capacity building in the region in the area of childhood obesity. This series of articles reflects the key outcome of the meeting and offers an analysis of the knowledge translation needed for evidence-based policy initiatives, a review of the research agenda and an evaluation of research capacity in the region. The goal of the papers is to inform the development of multidisciplinary and multisector research collaborations, which are essential to the implementation of successful childhood obesity prevention strategies in the region.

A research agenda to guide progress on childhood obesity prevention in Latin America.

Childhood obesity rates in Latin America are among the highest in the world. This paper examines and evaluates the many efforts underway in the region to reduce and prevent further increases in obesity, identifies and discusses unique research challenges and opportunities in Latin America, and proposes a research agenda in Latin America for the prevention of childhood obesity and concomitant non-communicable diseases. Identified research gaps include biological challenges to healthy growth across the life cycle, diet and physical activity dynamics, community interventions promoting healthy child growth, and rigorous evaluation of national food and activity programs and regulatory actions. Addressing these research gaps is critical to advance the evidence-based policy and practice in childhood obesity tailored to the Latin American context that will be effective in addressing obesity.

Pitfalls of the self-regulation of advertisements directed at children on Mexican television.

BACKGROUND: There are no academic studies that characterize advertisements directed at children from the companies that signed the self-regulation. OBJECTIVE: The aim of this paper was to assess the extent and nature of food advertisements and the persuasive techniques used to market unhealthy food and beverages (UFB) to children, by signatory companies of self-regulation. METHODS: From December 2012 to April 2013, 600 h of programming were recorded on the four broadcast public television channels in Mexico with the highest rating nationwide. Marketing aimed at children directly (broadcast on children's programmes or advertisements with a specific appeal to children) or indirectly (aimed at other target audiences with messages or scenes that link children to the product) were considered. RESULTS: About 74.9% (2148) of the total food and beverage advertisements tried to influence children directly and indirectly. Companies, which had signed the self-regulation, focused 92.7% of their advertisements on UFB. Of the total number, 23.9% were aimed at children, 7.1% at adolescents, 12.5% at parents and 56.2% at the general public. Most of these advertisements were broadcast on movies (29.8%), cartoons (18%), soap operas (17.6%), entertainment shows (17.2%) and sports programs (6.4%). CONCLUSION: Despite the self-regulation of television marketing, children were surrounded by UFB advertisements. Signatory companies influence children indirectly by targeting other audiences and by marketing during family television programs, which are also watched by children.

Orphan Spins in the S=5/2 Antiferromagnet CaFe_{2}O_{4}.

CaFe_{2}O_{4} is an anisotropic S=5/2 antiferromagnet with two competing A (↑↑↓↓) and B (↑↓↑↓) magnetic order parameters separated by static antiphase boundaries at low temperatures. Neutron diffraction and bulk susceptibility measurements, show that the spins near these boundaries are weakly correlated and a carry an uncompensated ferromagnetic moment that can be tuned with a magnetic field. Spectroscopic measurements find these spins are bound with excitation energies less than the bulk magnetic spin waves and resemble the spectra from isolated spin clusters. Localized bound orphaned spins separate the two competing magnetic order parameters in CaFe_{2}O_{4}.

Solitary Magnons in the S=5/2 Antiferromagnet CaFe_{2}O_{4}.

CaFe_{2}O_{4} is a S=5/2 anisotropic antiferromagnet based upon zig-zag chains having two competing magnetic structures, denoted as the A (↑↑↓↓) and B (↑↓↑↓) phases, which differ by the c-axis stacking of ferromagnetic stripes. We apply neutron scattering to demonstrate that the competing A and B phase order parameters result in magnetic antiphase boundaries along c which freeze on the time scale of ∼1 ns at the onset of magnetic order at 200 K. Using high resolution neutron spectroscopy, we find quantized spin wave levels and measure 9 such excitations localized in regions ∼1-2 c-axis lattice constants in size. We discuss these in the context of solitary magnons predicted to exist in anisotropic systems. The magnetic anisotropy affords both competing A+B orders as well as localization of spin excitations in a classical magnet.