Simultaneous Effect of Temperature and Irradiance on Growth and Okadaic Acid Production from the Marine Dinoflagellate Prorocentrum belizeanum

Benthic marine dioflagellate microalgae belonging to the genus Prorocentrum are a major source of okadaic acid (OA), OA analogues and polyketides. However, dinoflagellates produce these valuable toxins and bioactives in tiny quantities, and they grow slowly compared to other commercially used microalgae. This hinders evaluation in possible large-scale applications. The careful selection of producer species is therefore crucial for success in a hypothetical scale-up of culture, as are appropriate environmental conditions for optimal growth. A clone of the marine toxic dinoflagellate P. belizeanum was studied in vitro to evaluate its capacities to grow and produce OA as an indicator of general polyketide toxin production under the simultaneous influence of temperature (T) and irradiance (I0). Three temperatures and four irradiance levels were tested (18, 25 and 28 °C; 20, 40, 80 and 120 µE·m−2·s−1), and the response variables measured were concentration of cells, maximum photochemical yield of photosystem II (PSII), pigments and OA. Experiments were conducted in T-flasks, since their parallelepipedal geometry proved ideal to ensure optically thin cultures, which are essential for reliable modeling of growth-irradiance curves. The net maximum specific growth rate (µm) was 0.204 day−1 at 25 °C and 40 µE·m−2·s−1. Photo-inhibition was observed at I0 > 40 μEm−2s−1, leading to culture death at 120 µE·m−2·s−1 and 28 °C. Cells at I0 ≥ 80 µE·m−2·s−1 were photoinhibited irrespective of the temperature assayed. A mechanistic model for µm-I0 curves and another empirical model for relating µm-T satisfactorily interpreted the growth kinetics obtained. ANOVA for responses of PSII maximum photochemical yield and pigment profile has demonstrated that P. belizeanum is extremely light sensitive. The pool of photoprotective pigments (diadinoxanthin and dinoxanthin) and peridinin was not able to regulate the excessive light-absorption at high I0-T. OA synthesis in cells was decoupled from optimal growth conditions, as OA overproduction was observed at high temperatures and when both temperature and irradiance were low. T-flask culture observations were consistent with preliminary assays outdoors

La subfamilia Donaciinae (Coleoptera: Chrysomelidae) en México

The subfamily Donaciinae is distinguished from the rest of the leaf beetles by the aquatic larvae and semiaquatic adults. In Mexico, there are records for Donacia Fabricius, Neohaemonia Székessy, and Plateumaris Thomson. The study of this subfamily in Mexico is poor; thus, in the present work, a dichotomic key for the genera distributed in the country, a diagnosis, and photographs for the species are provided, with the objective of providing a tool that facilitates the identification of the Mexican Donaciinae that could be found in collections or in material from recent collects and thus increase the taxonomic and ecological knowledge of this subfamily. In addition, Neohaemonia flohri (Jacoby) is reported for the first time in Tlaxcala.La subfamilia Donaciinae se caracteriza del resto de los crisomélidos porque sus larvas son acuáticas y los adultos semiacuáticos. En México se han registrado los géneros Donacia Fabricius, Neohaemonia Székessy y Plateumaris Thomson. El estudio de esta subfamilia en México es limitado, por lo que en el presente trabajo se presenta una clave para los géneros distribuidos en el país y una diagnosis e ilustraciones de las especies con el objetivo de proveer una herramienta que facilite la identificación de los Donaciinae mexicanos que pudieran encontrarse en colecciones o en material de recientes colectas, y así incrementar el conocimiento taxonómico y ecológico de esta subfamilia. Se reporta a Neohaemonia flohri (Jacoby) por primera vez en Tlaxcala

Heterocycle-Based Multicomponent Reactions in Drug Discovery: From Hit Finding to Rational Design

In the context of the structural complexity necessary for a molecule to selectively display a therapeutical action and the requirements for suitable pharmacokinetics, a robust synthetic approach is essential. Typically, thousands of relatively similar compounds should be prepared along the drug discovery process. In this respect, heterocycle‐based multicomponent reactions offer advantages over traditional stepwise sequences in terms of synthetic economy, as well as the fast access to chemsets to study the structure activity relationships, the fine tuning of properties, and the preparation of larger amounts for preclinical phases. In this account, we briefly summarize the scientific methodology backing the research line followed by the group. We comment on the main results, clustered according to the targets and, finally, in the conclusion section, we offer a general appraisal of the situation and some perspectives regarding future directions in academic and private research

Método para la cuantificación fluoirimétrica de la enzima LDH en disolución

Número de publicación: ES2527796 A1 (29.01.2015) También publicado como: ES2527796 B1 (10.11.2015) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P201300775 (29.07.2013)La invención está dirigida al desarrollo de un método y creación de un kit para la cuantificación del efecto citotóxico y/o viabilidad celular ante agentes químicos (elemento, compuesto, mezcla o fármaco en cualquier de sus estados) y/o físicos (i.e. iluminación, temperatura, turbulencia, fluidodinámica, etc.) que puedan producir rotura de la membrana celular. El kit mide la liberación de la enzima citoplasmática lactato deshidrogenasa (LDH) proveniente de células muertas y/o lisadas. Esta enzima cataliza la oxidación del lactato, presente en el kit, a piruvato. Durante la reacción, el NAD+, también presente en el kit, es reducido a NADH. La concentración de LDH, se cuantifica a través de la fluorescencia del NADH formado. Las mediciones indirectas de la enzima LDH se realizan en el sobrenadante de cultivos celulares. El método es aplicable tanto en medios inorgánicos para microalgas como en medios comerciales para células animales y de insecto.Universidad de Almerí

Amelioration of BPSD-like phenotype and cognitive decline in SAMP8 mice model accompanied by molecular changes after treatment with I2-imidazoline receptor ligand MCR5

Behavioural and Psychological Symptoms of Dementia (BPSD), including fear-anxiety- and depressive-like behaviour, are present in Alzheimer's disease (AD), together with memory decline. I2-imidazoline receptors (I2-IRs) have been associated with neuropsychiatric and neurodegenerative disorders, further, I2-IR ligands have demonstrated a neuroprotective role in the central nervous system (CNS). In this study, we assessed the effect of the I2-IR ligand MCR5 on both cognitive and non-cognitive symptoms in the Senescence accelerated mice prone 8 (SAMP8) mouse model. Oral administration of I2-IR ligand MCR5 (5mg/kg/day for four weeks) in 10-month SAMP8 mice ameliorated both BPSD-like phenotype and cognitive decline by attenuating depressive-like behaviour, reducing fear-anxiety-like behaviour and improving cognitive performance using different tasks. Interaction of I2-IR ligand MCR5 with serotoninergic system did not account for behavioral or cognitive improvement, although changes in molecular pathways underlying depression and anxiety phenotype were observed. MCR5 increased levels of p-AKT, phosphorylated Glycogen synthase kinase 3 β (GSK3β) at Ser9 and phosphorylated mammalian target of rapamycin complex 1 (mTORC1) levels in SAMP8 treated mice compared to SAMP8 control. Moreover, MCR5 treatment altered NMDA2B phosphorylation, and decreased the protein levels of phosphorylated Cyclin-Dependent Kinase 5 (p-CDK5) and dopamine- and cAMP-regulated phosphoprotein of Mr 32 kDa phosphorylated at Thr75 (p-DARPP32), with a parallel increase in PKA and p-CREB levels. Consistent with these changes MCR5 attenuated neuroinflammation by decreasing expression of pro-inflammatory markers such as Tumor necrosis factor-alpha (Tnf-α), Interleukin 1β (Il-1β), Interleukin 6 (Il-6), and promoted synaptic plasticity by increasing levels of Postsynaptic density protein 95 (PSD95) as well as ameliorating Tropomyosin-related kinase B (TrkB) and Nerve growth factor receptor (NGFR) signalling. Collectively, these results increase the potential of highly selective I2-IR ligands as therapeutic agents in age-related BPSD and cognitive alterations

Estado actual de la Colección Coleopterológica de la Facultad de Estudios Superiores Zaragoza (CCFES-Z), UNAM

Se presenta el estado actual de la Colección Coleopterológica de la Facultad de Estudios Superiores Zaragoza (CCFES-Z), UNAM. La CCFES-Z está integrada por 28,189 ejemplares agrupados en 2,596 morfoespecies pertenecientes a los subórdenes Adephaga, Archostemata, Myxophaga y Polyphaga. El total de individuos corresponden a 10 superfamilias, 60 familias, 85 subfamilias, 238 tribus y 78 subtribus. Hasta el momento se han identificado 808 géneros y 1,207 especies. Entre los géneros mejor representados se encuentran Pachybrachis Chevrolat con 57 morfoespecies (Chrysomelidae), Phyllophaga Harris con 41 (Scarabaeidae), Agrilus Curtis con 39 (Brupestidae), Cryptocephalus Geoffroy con 33 (Chrysomelidae) y Systena Chevrolat con 30 (Chrysomelidae). Se cuenta con 60 ejemplares tipo de las especies Brachiacantha angulata Nestor-Arriola & Toledo-Hernández, B. brevicuspidata Nestor-Arriola & Toledo-Hernández, B. truncata Nestor-Arriola & Toledo-Hernández, Cephalocyclus ordonezi Dellacasa, Dellacasa & Gordon, Macrocopturus burserophagus Muñiz & Ordóñez, Mastostethus gracilis Rodríguez-Mirón y Phyllophaga villardoi Morón & Ordóñez-Reséndiz. Polyphaga es el suborden con mayor número de morfoespecies (2,372) y ejemplares (26,375); sin embargo, Adephaga con sólo tres familias tiene una alta representatividad, 8.5% y 6.4% del total de morfoespecies y ejemplares. Archostemata y Myxophaga están representados por un individuo y una especie, cada uno. Chrysomelidae es la familia más diversa con 859 morfoespecies y 11,295 ejemplares, seguida de Curculionidae y Cerambycidae. Los coleópteros que forman parte de la CCFES-Z documentan especies de 20 entidades federativas de México.The Coleopterological Collection of the Facultad de Estudios Superiores Zaragoza (CCFES-Z), UNAM has 28,189 specimens grouped in 2,596 morphospecies belonging to the suborders Adephaga, Archostemata, Myxophaga and Polyphaga. The specimens are classified into 10 superfamilies, 60 families, 85 subfamilies, 238 tribes and 78 subtribes. To date, 808 genera and 1,207 species have been identified. Pachybrachis Chevrolat with 57 morphospecies (Chrysomelidae), is the most diverse genus, following of Phyllophaga Harris with 41 (Scarabaeidae), Agrilus Curtis with 39 (Brupestidae), Cryptocephalus Geoffroy with 33 (Chrysomelidae), and Systena Chevrolat with 30 (Chrysomelidae). The collection housed type specimens of the species: Brachiacantha angulata Nestor-Arriola & Toledo-Hernández, B. brevicuspidata Nestor-Arriola & Toledo-Hernández, B. truncata Nestor-Arriola & Toledo-Hernández, Cephalocyclus ordonezi Dellacasa, Dellacasa & Gordon, Macrocopturus burserophagus Muñiz & Ordóñez, Mastostethus gracilis Rodríguez-Mirón and Phyllophaga villardoi Morón & Ordóñez-Reséndiz. Polyphaga is the suborder most diverse with 2,372 morphospecies and 26,375 specimens. However, Adephaga has only three families, and it has a high representativeness, 8.5% and 6.4% of the total of morphospecies and specimens. Archostemata and Myxophaga has one specimen and one species. Chrysomelidae is the family most diverse with 859 morphospecies and 11,295 specimens, following of Curculionidae and Cerambycidae. Beetles at the CCFES-Z represent species of 20 Mexican states

Synthesis, Characterization and HPLC Analysis of the (1 S,2 S,5 R)-Diastereomer and the Enantiomer of the Clinical Candidate AR-15512

Abstract: AR-15512 (formerly known as AVX-012 and WS-12) is a TRPM8 receptor agonist currently in phase 2b clinical trials for the treatment of dry eye. This bioactive compound with menthol-like cooling activity has three stereogenic centers, and its final structure and absolute configuration, (1R,2S,5R), have been previously solved by cryo-electron microscopy. The route of synthesis of AR-15512 has also been reported, revealing that epimerization processes at the C-1 can occur at specific stages of the synthesis. In order to confirm that the desired configuration of AR-15512 does not change throughout the process and to discard the presence of the enantiomer in the final product due to possible contamination of the initial starting material, both the enantiomer of AR-15512 and the diastereomer at the C-1 were synthesized and fully characterized. In addition, the absolute configuration of the (1S,2S,5R)-diastereomer was determined by X-ray crystallographic analysis, and new HPLC methods were designed and developed for the identification of the two stereoisomers and their comparison with the clinical candidate AR-15512

Phosphoenolpyruvate from Glycolysis and PEPCK Regulate Cancer Cell Fate by Altering Cytosolic Ca2+

Changes in phosphoenolpyruvate (PEP) concentrations secondary to variations in glucose availability can regulate calcium signaling in T cells as this metabolite potently inhibits the sarcoplasmic reticulum Ca2+/ATPase pump (SERCA). This regulation is critical to assert immune activation in the tumor as T cells and cancer cells compete for available nutrients. We examined here whether cytosolic calcium and the activation of downstream effector pathways important for tumor biology are influenced by the presence of glucose and/or cataplerosis through the phosphoenolpyruvate carboxykinase (PEPCK) pathway, as both are hypothesized to feed the PEP pool. Our data demonstrate that cellular PEP parallels extracellular glucose in two human colon carcinoma cell lines, HCT-116 and SW480. PEP correlated with cytosolic calcium and NFAT activity, together with transcriptional up-regulation of canonical targets PTGS2 and IL6 that was fully prevented by CsA pre-treatment. Similarly, loading the metabolite directly into the cell increased cytosolic calcium and NFAT activity. PEP-stirred cytosolic calcium was also responsible for the calmodulin (CaM) dependent phosphorylation of c-Myc at Ser62, resulting in increased activity, probably through enhanced stabilization of the protein. Protein expression of several c-Myc targets also correlated with PEP levels. Finally, the participation of PEPCK in this axis was interrogated as it should directly contribute to PEP through cataplerosis from TCA cycle intermediates, especially in glucose starvation conditions. Inhibition of PEPCK activity showed the expected regulation of PEP and calcium levels and consequential downstream modulation of NFAT and c-Myc activities. Collectively, these results suggest that glucose and PEPCK can regulate NFAT and c-Myc activities through their influence on the PEP/Ca2+ axis, advancing a role for PEP as a second messenger communicating metabolism, calcium cell signaling, and tumor biology

Production of extracts with anaesthetic activity from the culture of Heterosigma akashiwo in pilot-scale photobioreactors

The shear-sensitive microalga Heterosigma akashiwo is known to produce brevetoxin-like compounds that are active in voltage-dependent sodium channels. In this work, we present a study on the production of anaesthetic extracts from H. akashiwo biomass obtained in low-shear bioreactors at different growth phases. The photobioreactors (PBRs) used had specific configurations and were operated in such a way as to avoid cellular damage by hydrodynamic stress. Cultures were developed in small static-control flasks and PBRs with volumes ranging from 1.5 L to 200 L. The bioactivity of the produced extracts was assessed in vitro (Neuro-2a cell-based assay) and in vivo (Zebra fish model). Bioactivity depended slightly on the growth phase and culture system, with greater toxicity with the Neuro-2a model when stationary-phase extracts were used. Interestingly, extracts were not cytotoxic against other human cell lines. Steady production of anaesthetic bioactives was observed. In vivo anaesthetic efficacy, assessed with the Zebra fish model, was similar to that of commercial products, and without any observed mortality at 24-h post exposure

Sublethal effect of the toxic dinoflagellate Karlodinium veneficum on early life stages of zebrafish (Danio rerio)

Dinoflagellates of the genus Karlodinium are ichthyotoxic species that produce toxins including karlotoxins and karmitoxins. Karlotoxins show hemolytic and cytotoxic activities and have been associated with fish mortality. This study evaluated the effect of toxins released into the environment of Karlodinium veneficum strain K10 (Ebro Delta, NW Mediterranean) on the early stages of Danio rerio (zebrafish). Extracts of the supernatant of K10 contained the mono-sulfated KmTx-10, KmTx-11, KmTx-12, KmTx-13, and a di-sulfated form of KmTx-10. Total egg mortality was observed for karlotoxin concentration higher than 2.69 μg L−1. For 1.35 μg L−1, 87% of development anomalies were evidenced (all concentrations were expressed as KmTx-2 equivalent). Larvae of 8 days postfertilization exposed to 1.35 µg L−1 presented epithelial damage with 80% of cells in the early apoptotic stage. Our results indicate that supernatants with low concentration of KmTxs produce both lethal and sublethal effects in early fish stages. Moreover, apoptosis was induced at concentrations as low as 0.01 μg L−1. This is of great relevance since detrimental long-term effects due to exposure to low concentrations of these substances could affect wild and cultured fish