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Some effects have been evidenced during several earthquakes around the world. For example, the liquefaction phenomenon, and structural collapse, among others. However, granular soil behaviour during this event has not been completely understood; this is proved by the number of investigations in physical models, constitutive models, and laboratory testing proposals about this topic. A question appears at this point: when do the effects take place? To cope with this issue, it is proposed to create an experimental model composed of a Single Degree of Freedom Oscillator (SDOFO) designed to try to assess the liquefaction. Likewise, the device could transmit cyclic loadings to the soil. This SDOFO was an electromechanical oscillator servo-controlled appropriated to manage the frequency of excitation and amplitude of the oscillatory movement. The measurement methodology was based on computer vision using Open CV by Python, which allowed measuring displacements and times of the SDOFO instead of using LVDT sensors located directly at the actuator; thus, computer vision permitted a “free movement” of the actuator similar to the actual behavior of buildings in seismic events. The samples required for this study were the Guamo sand collected in a natural deposit in Colombia (South America) and the Ottawa sand to compare results. A simple criterion was used to try to determine the possible liquefaction onset. It was defined based on the evolution of displacements relying on the number of cyclical loads. According to the results, it was able to define that the relationship between the excitation frequency, the amplitude of the oscillatory movement, and the number of cycles required to reach the possible liquefaction state was inverse.

El presente trabajo es una recopilación de casos comprobados de actividad biológica de extractos y sustancias de origen vegetal para el control de arvenses, plagas y enfermedades en el sector agrícola. De esta forma, se pone en evidencia que una de las familias con mayor número de reportes en este tipo de actividad biológica es la Piperaceae, esto las convierte en una de las más promisorias para la búsqueda de extractos o compuestos que tengan aplicaciones en la solución de problemas fitosanitarios. Debido a la importancia de Piperaceae y en especial del género Piper, los grupos de investigación BioGuavio/ AgroUDEC de la Universidad de Cundinamarca y Estudio Químico y de Actividad Biológica de Rutaceae y Myristicaceae Colombianas de la Universidad Nacional de Colombia con el apoyo de Colciencias, desarrollan un proyecto titulado Bioprospección participativa de comunidades vegetales asociadas a la familia Piperaceae en la región del Sumapaz medio y bajo occidental” (Código 1101-05-17783) que busca identificar y comprobar en las especies prospectadas aplicaciones de interés en el sector agrícola.

This report describes how postoperative delirium in an elderly man during COVID-19 pandemic led to a serious event involving a central venous catheter. Delirium is a common cause of perioperative morbidity and mortality, and is characterised by an alteration in consciousness and perception and a reduced ability to focus, sustain or shift attention. The event was analysed by a multidisciplinary committee which developed a risk stratification delirium protocol in order to prevent similar events in the future., (Copyright © 2024 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

Oxidative stress (OS) plays an essential role in the pathophysiology of Duchenne muscular dystrophy (DMD). However, the actors that regulate OS need to be better studied. We aimed to evaluate whether NFE2-like bZIP transcription factor 2 (Nrf2), glutathione, malondialdehyde (MDA), and protein carbonyl concentrations change according to the disease severity in DMD patients. Moreover, we assessed whether OS correlated with muscle injury, clinical characteristics, physical activity, and antioxidant food consumption (AFC). A total of 28 DMD patients participated in this study. OS markers, metabolic indicators, and enzymatic markers of muscle injury were measured in circulation. Muscle injury was measured with clinical scales, and physical activity and AFC were evaluated with questionnaires. Nrf2 concentration was lower ( p ≤ 0.01), and malondialdehyde concentration was higher ( p < 0.05) in non-ambulatory patients than in ambulatory patients. Nrf2 correlated with age ( rho = -0.387), Vignos scale ( rho = -0.328), GMFCS scale ( rho = -0.399), and Brooke scale scores ( rho = -0.371) ( p < 0.05). MDA correlated with Vignos ( rho = 0.317) and Brooke scale scores ( rho = 0.414) ( p ≤ 0.05). In conclusion, DMD patients with the worst muscle function had more significant oxidative damage and lower antioxidant function than DMD patients with better muscle function.

Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a potentially lethal condition to be taken into account in pregnant women, where the situation is favored by the characteristic physiological changes of the pregnancy, childbirth and the puerperium. The management of this pathology in this type of patient is based on anticoagulation, with the benefits and drawbacks that this implies. We present the case of a pregnant woman with massive DVT and the issues are discussed, such as the method of delivery (vaginal vs. cesarean section) or the management of treatment (LMWH vs. UFH) in order to obtain the safest situation for the patient., (Copyright © 2021 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.)

Inhibition of tumour promotion in multistage chemical carcinogenesis is considered a promising strategy for cancer chemoprevention. In an ongoing investigation of bioactive secondary metabolites from Celastraceae species, five new dihydro-β-agarofuran sesquiterpenes (1-5), named Chiapens A-E, and seventeen known ones, were isolated from Maytenus chiapensis. Their structures were elucidated by extensive NMR spectroscopic and mass spectrometric techniques, and their absolute configurations were determined by circular dichroism studies, chemical correlations and biogenic means. The isolated compounds, along with twenty known sesquiterpenes, previously isolated from Zinowiewia costaricensis, have been tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorpol-13-acetate (TPA). Thirty three compounds from this series showed stronger effects than that of β-carotene, the reference inhibitor. The structure-activity relationship (SAR) analysis revealed that the type of substituent, in particular at the C-1 position of the sesquiterpene scaffold, was able to modulate the anti-tumour promoting activity. Compounds 3, 6, and 33 showed significant effects in an in vivo two-stage mouse-skin carcinogenesis model., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

The first case of neonatal Chagas was reported in Mexico in 1998, but there have been no studies since then. Therefore, we investigated the rates of congenital infection of Trypanosoma cruzi by examining the seroprevalence among 1448 pregnant women in Oaxaca, Jalisco and Mexico City. We performed ELISAs to screen for recombinant and total antigens in mothers, and examined the frequency of congenital T. cruzi transmission by PCR with cord blood and antibody testing in children when they reached two years old. Our results showed that the prevalence of infection in pregnant women was 7.32% (106/1448) overall, and 4.4% (35/794) in Oaxaca, 12.02% (67/557) in Jalisco and 4.12% (4/97) in the Mexico City. In Oaxaca, T. cruzi infection was detected by PCR in 20% (7/35) of infants born to seroreactive mothers and 11.9% (8/67) in Jalisco. No infections were identified in infants from the Mexico City. From these only eleven serological follow up their children are agree to take blood. Therefore, the maternal-fetal overall transmission rate was 4.08% (4/98) in Oaxaca and 9.1% (3/33) in Jalisco 1.5% (1/65) children with positive serology were given specific treatment Chagas. In conclusion, these are the first reports of the rates of congenital Chagas disease in Mexico. The seroprevalence was higher in mothers from Jalisco, and could be related to that there is not the periodic fumigation of the transmitting vector performed in that state. The high rates of maternal-fetal transmission found in Oaxaca could be related to the differences of pathogenicity of trypanosome. No association between both the rate of congenital transmission and the gynecologic anthropometric data was observed., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Multidrug resistance (MDR) is one of the main challenges in the chemotherapy of cancer, malaria, and other important diseases. Here, we report the inhibitory activity of a series of 76 dihydro-beta-agarofuran sesquiterpenes, tested on NIH-3T3 cells expressing the human P-glycoprotein (Pgp) multidrug transporter, to establish quantitative comparisons of their respective abilities to block the drug transport activity. The screening was performed on the basis of the ability of sesquiterpenes to modulate the intracellular accumulation of the classical Pgp substrate daunorubicin. To understand the structural basis for inhibitory activity and guide the design of more potent Pgp inhibitors, we have performed a three-dimensional quantitative structure-activity relationship model using the comparative molecular similarity indices analysis (CoMSIA). The most salient features of these requirements are in the region of the substituents at the C-2, C-3, and C-8 positions, which seem to be critical for determining the overall effectiveness of sesquiterpenes as Pgp inhibitors.

In an intensive study of South American medicinal plants, herein we report the isolation, structure elucidation and biological activity of fourteen new and five known dihydro-beta-agarofuran sesquiterpenes from the leaves of Zinowiewia costaricensis (1-19). Their structures were determined by means of (1)H and (13)C NMR spectroscopic studies, including homonuclear and heteronuclear correlation experiments. The absolute configurations of the new compounds were determined by CD studies, chemical correlations or biogenetic grounds. All the natural compounds and derivative 20 have been tested on human MDR1-transfected NIH-3T3 cells, to determine their ability to revert the multidrug resistance phenotype due to P-glycoprotein overexpression. Six compounds from this series (1, 8, 11, 12, 13 and 14) showed similar effectiveness to the classical P-glycoprotein modulator verapamil when reversing resistance to daunorubicin, but it is up to sixteen times greater than that of verapamil when reversing resistance to vinblastine. The structure-activity relationships are discussed.

Seven new sesquiterpenes (1-7) with a 'dihydro-beta-agarofuran' (= 5,11-epoxy-5beta,10alpha-eudesmane) skeleton were isolated from Crossopetalum tonduzii. Their structures were elucidated spectroscopically, especially by means of homo- and heteronuclear NMR correlation (COSY, ROESY, HSQC, and HMBC). The absolute configurations of the new compounds were determined by circular dichroism (CD) studies and by chemical correlations via the derivatives 8-11. The new compounds showed moderate antitumor-promoting effects with respect to the activation of the Epstein-Barr virus early antigen (EBV-EA).