New insights into the domain of unknown function (DUF) of EccC5, the pivotal ATPase providing the secretion driving force to the ESX-5 secretion system.

Type VII secretion (T7S) systems, also referred to as ESAT-6 secretion (ESX) systems, are molecular machines that have gained great attention due to their implications in cell homeostasis and in host-pathogen interactions in mycobacteria. The latter include important human pathogens such as Mycobacterium tuberculosis (Mtb), the etiological cause of human tuberculosis, which constitutes a pandemic accounting for more than one million deaths every year. The ESX-5 system is exclusively found in slow-growing pathogenic mycobacteria, where it mediates the secretion of a large family of virulence factors: the PE and PPE proteins. The secretion driving force is provided by EccC5, a multidomain ATPase that operates using four globular cytosolic domains: an N-terminal domain of unknown function (EccC5DUF) and three FtsK/SpoIIIE ATPase domains. Recent structural and functional studies of ESX-3 and ESX-5 systems have revealed EccCDUF to be an ATPase-like fold domain with potential ATPase activity, the functionality of which is essential for secretion. Here, the crystal structure of the MtbEccC5DUF domain is reported at 2.05 Šresolution, which reveals a nucleotide-free structure with degenerated cis-acting and trans-acting elements involved in ATP binding and hydrolysis. This crystallographic study, together with a biophysical assessment of the interaction of MtbEccC5DUF with ATP/Mg2+, supports the absence of ATPase activity proposed for this domain. It is shown that this degeneration is also present in DUF domains from other ESX and ESX-like systems, which are likely to exhibit poor or null ATPase activity. Moreover, based on an in silico model of the N-terminal region of MtbEccC5DUF, it is hypothesized that MtbEccC5DUF is a degenerated ATPase domain that may have retained the ability to hexamerize. These observations draw attention to DUF domains as structural elements with potential implications in the opening and closure of the membrane pore during the secretion process via their involvement in inter-protomer interactions.

Colombian Scorpion Centruroides margaritatus: Purification and Characterization of a Gamma Potassium Toxin with Full-Block Activity on the hERG1 Channel.

The Colombian scorpion Centruroides margaritatus produces a venom considered of low toxicity. Nevertheless, there are known cases of envenomation resulting in cardiovascular disorders, probably due to venom components that target ion channels. Among them, the humanether-à-go-go-Related gene (hERG1) potassium channels are critical for cardiac action potential repolarization and alteration in its functionality are associated with cardiac disorders. This work describes the purification and electrophysiological characterization of a Centruroides margaritatus venom component acting on hERG1 channels, the CmERG1 toxin. This novel peptide is composed of 42 amino acids with a MW of 4792.88 Da, folded by four disulfide bonds and it is classified as member number 10 of the γ-KTx1 toxin family. CmERG1 inhibits hERG1 currents with an IC50 of 3.4 ± 0.2 nM. Despite its 90.5% identity with toxin É£-KTx1.1, isolated from Centruroides noxius, CmERG1 completely blocks hERG1 current, suggesting a more stable plug of the hERG channel, compared to that formed by other É£-KTx.

Antiseizure potential of peptides from the venom of social wasp Chartergellus communis against chemically-induced seizures.

Epilepsy is one of the most common neurological diseases in the world. The objective of this research was to investigate a new peptide from the venom of the social wasp Chartergellus communis useful to the study or pharmacotherapy of epilepsy. The wasps were collected, and their venom was extracted. Afterward, the steps of fractionation, sequencing, and identification were carried out to obtain four peptides. These molecules were synthesized for behavioral evaluation tests and electroencephalographic assays to determine their antiseizure potential (induction of acute seizures using the chemical compounds, pentylenetetrazole - PTZ, and pilocarpine - PILO) and analysis of neuropharmacological profile (general spontaneous activity and alteration in motor coordination). Chartergellus-CP1 (i.c.v. - 3.0 µg/animal) caused beneficial alterations in some of the parameters evaluated in both models: PTZ (latency and duration of maximum seizures) and PILO (latency and duration of, and protection against, maximum seizures, and reduction of the median of the seizure scores. When evaluated in 3 doses in the seizure model induced by PILO, the dose of 3.0 µg/animal protected the animals against seizures, with an estimated ED50 of 1.49 µg/animal. Electroencephalographic evaluation of Chartergellus-CP1 showed an improvement in latency, quantity, and percentage of protection against generalized electroencephalographic seizures in the PILO model. Further, Chartergellus-CP1 did not cause adverse effects on general spontaneous activity and motor coordination of animals. This study demonstrated how compounds isolated from wasps' venom may be important resources in the search for new drugs. Such compounds can be considered valuable therapeutic and biotechnological tools for the study and future treatment of epileptic disorders. In this context, a peptide that is potentially useful for epilepsy pharmacotherapy was identified in the venom of C. communis.

Structural and functional characterization of toxic peptides purified from the venom of the Colombian scorpion Tityus macrochirus.

The soluble venom of the scorpion Tityus macrochirus was separated by chromatographic procedures and three homogeneous peptides were obtained and their primary structures were determined. They were called: Tma1-Tma3, from the abbreviated name of the scorpion. Tma1 is a peptide containing 65 amino acids with four disulfide linkages and a molecular weight of 7386.2 Da. It is a mammalian toxin, shown to affect human sodium-channels sub-types hNav1.6 and hNav1.4. Tma2 and Tma3 are peptides containing 69 amino acids linked by four disulfide bonds, molecular weights 7819.7 and 7830.0 Da, respectively. They do not affect human sodium-channels but are lethal to insects (crickets). A phylogenic analysis of the three peptides and those of other toxic peptides isolated from the genus Tityus and Centruroides were grouped together and analyzed, permitting to obtain a topology with two main clades, one includes most sodium-channel anti-insect scorpion toxins and others includes mostly sodium-channel scorpion toxins anti-mammalian. Tma1 segregates among a group of well-studied ß-class toxins of other Tityus species such as T. discrepans, T. obscurus and T. pachyurus. Tma2 and Tma3 are associated with anti-insect toxins, particularly with one of T. obscurus. This phylogenetic analysis confirms and enforces our experimental results obtained with these three new sodium-channel scorpion toxins.

An Alkaloid from Scorpion Venom: Chemical Structure and Synthesis.

While most scorpion venom components identified in the past are peptidic or proteinic in nature, we report here a new alkaloid isolated from the venom of the Mexican scorpion Megacormus gertschi. Nuclear magnetic resonance and mass spectrometric investigations elucidate the structure of the alkaloid as ( Z)- N-(2-(1 H-imidazol-4-yl)ethyl)-3-(4-hydroxy-3-methoxyphenyl)-2-methoxyacrylamide (1). A chemical method of synthesizing this alkaloid is also described. Although abundant in venom, the above alkaloid was not found to have insecticidal activity. Structural analysis suggests that this venom alkaloid might be of potential interest for evaluating its medicinal effect.

Spodoptera frugiperda (J. E. Smith) Aminopeptidase N1 Is a Functional Receptor of the Bacillus thuringiensis Cry1Ca Toxin.

Bacillus thuringiensis Cry1Ca is toxic to different Spodoptera species. The aims of this work were to identify the Cry1Ca-binding proteins in S. frugiperda, to provide evidence on their participation in toxicity, and to identify the Cry1Ca amino acid residues involved in receptor binding. Pulldown assays using Spodoptera frugiperda brush border membrane vesicles (BBMV) identified aminopeptidase N (APN), APN1, and APN2 isoforms as Cry1Ca-binding proteins. Cry1Ca alanine substitutions in all residues of domain III ß16 were characterized. Two ß16 nontoxic mutants (V505A and S506A) showed a correlative defect on binding to the recombinant S. frugiperda APN1 (SfAPN1). Finally, silencing the expression of APN1 transcript, by double-stranded RNA (dsRNA) feeding, showed that silenced larvae are more tolerant of the Cry1Ca toxin, which induced less than 40% mortality in silenced larvae whereas nonsilenced larvae had 100% mortality. Overall, our results show that Cry1Ca relies on APN1 binding through domain III ß16 to impart toxicity to S. frugiperdaIMPORTANCEBacillus thuringiensis Cry toxins rely on receptor binding to exert toxicity. Cry1Ca is toxic to different populations of S. frugiperda, a major corn pest in America. Nevertheless, the S. frugiperda midgut proteins that are involved in Cry1Ca toxicity have not been identified. Here we identified aminopeptidase N1 (APN1) as a functional receptor of Cry1Ca. Moreover, we showed that Cry1Ca domain III ß16 is involved in APN1 binding. These results give insights on potential target sites for improving Cry1Ca toxicity to S. frugiperda.

Characterization of two peptides isolated from the venom of social wasp Chartergellus communis (Hymenoptera: Vespidae): Influence of multiple alanine residues and C-terminal amidation on biological effects.

Chatergellus communis is a wasp species endemic to the neotropical region and its venom constituents have never been described. In this study, two peptides from C. communis venom, denominated Communis and Communis-AAAA, were chemically and biologically characterized. In respect to the chemical characterization, the following amino acid sequences and molecular masses were identified: Communis: Ile-Asn-Trp-Lys-Ala-Ile-Leu-Gly-Lys-Ile-Gly-Lys-COOH (1340.9Da) Communis-AAAA: Ile-Asn-Trp-Lys-Ala-Ile-Leu-Gly-Lys-Ile-Gly-Lys-Ala-Ala-Ala-Ala-Val-Xle-NH2 (1836.3Da). Furthermore, their biological effects were compared, accounting for the differences in structural characteristics between the two peptides. To this end, three biological assays were performed in order to evaluate the hyperalgesic, edematogenic and hemolytic effects of these molecules. Communis-AAAA, unlike Communis, showed a potent hemolytic activity with EC50=142.6µM. Moreover, the highest dose of Communis-AAAA (2nmol/animal) induced hyperalgesia in mice. On the other hand, Communis (10nmol/animal) was able to induce edema but did not present hemolytic or hyperalgesic activity. Although both peptides have similarities in linear structures, we demonstrated the distinct biological effects of Communis and Communis-AAAA. This is the first study with Chartegellus communis venom, and both Communis and Communis-AAAA are unpublished peptides.

[Urinary lithiasis as a systemic disease.] / La litiasis urinaria como enfermedad sistémica.

Urinary lithiasis is a prevalent disorder of uncertain origin which provokes health problems through potential harm to the urinary system, renal parenchyma or the body as a whole, with a frequent trend to relapse. Historically urinary calculi have been studied and treated as an isolated disease but nowadays we know more about their connection with other pathological entities. In a small percentage of patients, diseases like primary hyperparathyroidism, tubular renal acidosis, inflammatory bowel disease or bariatric surgery have a fairly well studied physiopathological link with kidney stones. However, papers have been published recently describing connections between prevalent diseases such as bone disease or metabolic syndrome and nephrolithiasis. Attempts to prevent or treat these affections can possibly influence the other's prevalence since their trend to increase is clear in western countries.

La litiasis urinaria como enfermedad sistémica / Urinary lithiasis as a systemic disease

La litiasis urinaria es una patología prevalente de origen desconocido, que acarrea problemas al paciente tanto por el potencial daño a la vía urinaria, parénquima renal y organismo en su conjunto como por la tendencia frecuente de esta enfermedad a la recidiva. Historicamente se ha estudiado y tratado como una alteración aislada pero hoy en día cada vez conocemos mas sus conexiones con un conjunto de entidades patológicas con las que frecuentemente concurre. En un pequeño porcentaje de pacientes, enfermedades como el hiperparatiroidismo primario y la acidosis tubular renal tienen una clara correlación etiológica con la litiasis así como enfermedades inflamatorias digestivas y cirugía bariatrica. Sin embargo la conexión entre enfermedades frecuentes en la población, como la osteoporosis, el síndrome metabólico y la nefrolitiasis está en estudio, por si su prevención puede contribuir a frenar la tendencia al aumento de la incidencia y prevalencia de estas patologías en la sociedad occidental en las últimas décadas

Urinary lithiasis is a prevalent disorder of uncertain origin which provokes health problems through potential harm to the urinary system, renal parenchyma or the body as a whole, with a frequent trend to relapse. Historically urinary calculi have been studied and treated as an isolated disease but nowadays we know more about their connection with other pathological entities. In a small percentage of patients, diseases like primary hyperparathyroidism, tubular renal acidosis, inflammatory bowel disease or bariatric surgery have a fairly well studied physiopathological link with kidney stones. However, papers have been published recently describing connections between prevalent diseases such as bone disease or metabolic syndrome and nephrolithiasis. Attempts to prevent or treat these affections can possibly influence the other´s prevalence since their trend to increase is clear in western countries

Comparative proteomic analysis of female and male venoms from the Mexican scorpion Centruroides limpidus: Novel components found.

Venom from male and female scorpions of the species Centruroides limpidus were separated by HPLC and their molecular masses determined by mass spectrometry. The relative concentration of components eluting in equivalent retention times from the HPLC column shows some differences. A new peptide with 29 amino acids, cross-linked by three disulfide bonds was found in male scorpions and its structure determined. Another unknown peptide present in female venom, with sequence identity similar to K+-channel blocking peptide was isolated. This peptide contains 39 amino acid residues linked by three disulfide bonds. Due to sequence similarities, a systematic number (αKTx2.18) was assigned. Venom from male and female scorpions was separated by Sephadex G-50 gel filtration. Components of fraction I of this chromatogram were analyzed by two-dimensional gel electrophoresis and 41 spots were selected (20 from female and 21 from male). The spots were excised from the gel, enzymatically digested and sequenced by LC-MS/MS. This procedure allowed the identification of several proteins containing similar amino acid sequence of other known proteins registered on UniProt database. Among these proteins the presence of metalloproteinases (proteolytic enzymes), hyaluronidases and phosphatases were experimentally determined and shown to be present in both venom samples. The results shown here should help further work aimed at fully identification of the structure and function of venom components form C. limpidus male and female scorpions.

Isolation, chemical and functional characterization of several new K(+)-channel blocking peptides from the venom of the scorpion Centruroides tecomanus.

Six new peptides were isolated from the venom of the Mexican scorpion Centruroides tecomanus; their primary structures were determined and the effects on ion channels were verified by patch-clamp experiments. Four are K(+)-channel blockers of the α-KTx family, containing 32 to 39 amino acid residues, cross-linked by three disulfide bonds. They all block Kv1.2 in nanomolar concentrations and show various degree of selectivity over Kv1.1, Kv1.3, Shaker and KCa3.1 channels. One peptide has 42 amino acids cross-linked by four disulfides; it blocks ERG-channels and belongs to the γ-KTx family. The sixth peptide has only 32 amino acid residues, three disulfide bonds and has no effect on the ion-channels assayed. It also does not have antimicrobial activity. Systematic numbers were assigned (time of elution on HPLC): α-KTx 10.4 (time 24.1); α-KTx 2.15 (time 26.2); α-KTx 2.16 (time 23.8); α-KTx 2.17 (time 26.7) and γ-KTx 1.9 (elution time 29.6). A partial proteomic analysis of the short chain basic peptides of this venom, which elutes on carboxy-methyl-cellulose column fractionation, is included. The pharmacological properties of the peptides described in this study may provide valuable tools for understanding the structure-function relationship of K(+) channel blocking scorpion toxins.

Swan song: el advenimiento del núcleo psicótico / Swan song: the advent of the psychotic nucleus

Introducción: Diversas formas de expresión artística, como la literatura y el cine, constituyen fuentes inagotables para el estudio de la enfermedad mental. La aplicación de modelos psicodinámicos puede contribuir al entendimiento del espectro entre los trastornos de personalidad y la psicosis, enriqueciendo su abordaje fenomenológico en la práctica clínica psiquiátrica. Objetivo: Examinar, desde puntos de vista psicodinámicos, al personaje central de la película estadounidense Black Swan, así como la naturaleza de sus síntomas psicóticos. Métodos: Revisión de fuentes y corrientes teóricas relevantes. Resultados y conclusiones: El análisis resalta la utilidad de considerar un modelo dimensional psicodinámicamente orientado en el entendimiento de las llamadas incursiones psicóticas; así como la aplicabilidad de teorías psicoanalíticas de la psicosis a la práctica psiquiátrica general, buscando un abordaje clínico más flexible, y, quizá, más cercano a la experiencia subjetiva del paciente…

Introduction: Different forms of artistic expression, such as literature and cinema, constitute an inexhaustible source for the study of mental illness. The use of psychodynamic models may contribute to a better understanding of the spectrum between personality disorders and the psychosis spectrum, thus enriching the phenomenological approach in the psychiatric clinical practice. Objective: To examine from psychodynamic standpoints the main character of the American film Black Swan, and the nature of her psychotic symptoms. Methods: Re-viewing of sources and relevant theoretical currents. Results and conclusions: Analysis shows the usefulness of a psychodynamically- oriented dimensional model for understanding the so-called psychotic breaks as well as the applicability of psychoanalytic psychosis theories in general psychiatric practice, as they may provide a more flexible clinical approach, closer to the patient’s subjective experience…

[Swan Song: The Advent of the Psychotic Nucleus]. / Swan song: el advenimiento del núcleo psicótico.

INTRODUCTION: Different forms of artistic expression, such as literature and cinema, constitute an inexhaustible source for the study of mental illness. The use of psychodynamic models may contribute to a better understanding of the spectrum between personality disorders and the psychosis spectrum, thus enriching the phenomenological approach in the psychiatric clinical practice. OBJECTIVE: To examine from psychodynamic standpoints the main character of the American film Black Swan, and the nature of her psychotic symptoms. METHODS: Reviewing of sources and relevant theoretical currents. RESULTS AND CONCLUSIONS: Analysis shows the usefulness of a psychodynamically- oriented dimensional model for understanding the so-called psychotic breaks as well as the applicability of psychoanalytic psychosis theories in general psychiatric practice, as they may provide a more flexible clinical approach, closer to the patient's subjective experience.

Sistemas de información, centro de control y GMAO en centros sanitarios / Information system, control center and health centers CMMS

En edificios complejos y sobre todo en hospitalaes, los sistemas y equipos que requieren de vigilancia, conrol y análisis de datos son múltiples y complejos y como cada uno pertenece a un periodo tecnológico distitno se hace realmente difícil extraer la inforación necesaria de los mismos. Si además, a este cóctel peligrosos le smamos que las instalaciones cuentan con más de 30 años y los sistemas de información del mantenimiento eran de poca utilidad, teníamos un problema o como se suele decir en elmundo de la calidad existe una oportunidad de mejora. Lo que este artículo plantea es algomuynormal en la industria, por la estandarización en sistemas y equipos, pero muy poco visto en el mundo sanitario , por la miscelánea de productos y el sobrecoste my pocas veces asumido; trat de cómo la inforamción procedent de equios, instalaciones y mantenimiento puede confluir en un solo punto. La información dispersa para su análisis requiere de un gran esfuerzo, sin embargo, si fusionamos las distintas fuentes en un solo elemento obtendremos el máximo rendimiento del uso de las tecnologías. La propuesta queen este caso presentamos reúne la mayor información que sobre este tema existe actualmente en el mercado (AU)

Here arises how the information from equipment, facilities and maintenance can converge at one point The scatted information for analysis requires a great effort, however, if fusion different sources into a single element gets the full benefits of technology (AU)

Novel antimicrobial peptides isolated from skin secretions of the Mexican frog Hyla eximia.

In this work, we describe the original characterization of peptides and proteins present in the skin secretions of the Mexican amphibian Hyla eximia. To this purpose, a novel water/dark extraction method, as well as the classic electrical stimulation procedure, was applied in order to extract the skin secretion. Two novel antimicrobial peptides He-1 and He-2 were sequenced. In addition, a molecular mass fingerprint revealed more than one hundred different molecules. Eight peptides in homogeneous form were assayed against five species of bacteria. Thereafter, the peptide He-2 demonstrated high antiparasitic activity against ookinete forms of malaria parasites at low concentration.