Synergism in Two-Component Insecticides with Dillapiole against Fall Armyworm.

The fall armyworm (Spodoptera frugiperda), a polyphagous insect pest, is a major threat to food production, rapidly spreading through all the tropical areas in the world. Resistance has developed to the control protocols used so far (pyrethroids, organophosphorus, and genetically modified plants), and alternative strategies must be found. The bioactivity in essential oils is usually associated with the major constituents, but synergistic interactions among the constituents (even minor ones) can improve the levels of activity considerably. Herein, we tested the insecticidal activity of several constituents of the essential oil from Piper aduncum, an Amazonian Piperaceae, both separately and as binary mixtures, through their application on the dorsal side of the larva pronotum. Dillapiole proved to be, isolated, the most active compound in this oil (LD50 = 0.35 ppm). In binary mixtures, a strong synergistic effect was observed for the pairs of dillapiole with ß-caryophyllene (LD50 = 0.03 ppm), methyl eugenol (LD50 = 0.05 ppm), and α-humulene (LD50 = 0.05 ppm). In some cases, however, antagonism was recorded, as for dillapiole + ß-pinene (LD50 = 0.44 ppm). The use of binary mixtures of essential oil constituents as low-environmental-toxicity insecticides allows a fine tuning of the insecticidal activity, and the exploitation of synergy effects.

Acute toxicity and antitumor potential of 1,3,4-trisubstituted-1,2,3-triazole dhmtAc-loaded liposomes on a triple-negative breast cancer model.

For the first time, compounds developed from the 1,2,3-triazole scaffold were evaluated as novel drugs to treat triple-negative breast cancer (TNBC). Four organic salts were idealized as nonclassical bioisosteres of miltefosine, which is used in the topical treatment for skin metastasizing breast carcinoma. Among them, derivative dhmtAc displayed better solubility and higher cytotoxicity against the human breast adenocarcinoma cell line and mouse 4T1 cell lines, which are representatives of TNBC. In vitro assays revealed that dhmtAc interferes with cell integrity, confirmed by lactate dehydogenase leakage. Due to its human peripheral blood mononuclear cell (PBMC) toxicity, dhmtAc in vivo studies were carried out with the drug incorporated in a long-circulating and pH-sensitive liposome (SpHL-dhmtAc), and the acute toxicity in BALB/c mice was determined. Free dhmtAc displayed cardiac and pulmonary toxicity after the systemic administration of 5 mg/kg doses. On the other hand, SpHL-dhmtAc displayed no toxicity at 20 mg/kg. The in vivo antitumor effect of SpHL-dhmtAc was investigated using the 4T1 heterotopic murine model. Intravenous administration of SpHL-dhmtAc reduced the tumor volume and weight, without interfering with the body weight, compared with the control group and the dhmtAc free form. The incorporation of the triazole compound in the liposome allowed the demonstration of its anticancer potential. These findings evidenced 1,3,4-trisubstituted-1,2,3-triazole as a promising scaffold for the development of novel drugs with applicability for the treatment of patients with TNBC.

NO mediates the effect of the synthetic natriuretic peptide NPCdc on kidney and aorta in nephrectomised rats.

NPCdc is a synthetic natriuretic peptide that was originally derived from another peptide, the NP2_Casca, isolated from Crotalus durissus cascavella venom. These molecules share 70% structural homology with natriuretic peptides obtained from different species, including humans. NP2_Casca induces vasorelaxation and increases nitric oxide levels independently of natriuretic peptide receptors A and B. This study aimed to investigate whether NPCdc-induced hypotension in control rats and rats with a reduced kidney mass is associated with effects on the glomerular filtration rate, NADPH oxidase activity and components downstream of natriuretic peptide receptor C (NPR-C). Anaesthetized Wistar rats that were subjected to a sham operation and 5/6 nephrectomy (5/6Nx) were infused with saline (vehicle) or NPCdc (7.5 µg/kg/min) for 70 min. The NPCdc treatment decreased the mean arterial pressure and NADPH oxidase activity while simultaneously increasing the glomerular filtration rate, fractional Na+ excretion and nitric oxide level. After 70 min, the levels of p-AKT Ser-473, p-eNOS Ser-1177, p-nNOS Ser-1417 and p-iNOSTyr-151 were not affected. However, p-ERK1/2 Thr-202/Tyr-204 levels were altered. Thus, nitric oxide and components of NPR-C signalling mediate the effects of NPCdc. The results suggest a potential therapeutic application of this peptide for cardiorenal syndrome.

LyeTxI-b, a Synthetic Peptide Derived From Lycosa erythrognatha Spider Venom, Shows Potent Antibiotic Activity in Vitro and in Vivo.

The antimicrobial peptide LyeTxI isolated from the venom of the spider Lycosa erythrognatha is a potential model to develop new antibiotics against bacteria and fungi. In this work, we studied a peptide derived from LyeTxI, named LyeTxI-b, and characterized its structural profile and its in vitro and in vivo antimicrobial activities. Compared to LyeTxI, LyeTxI-b has an acetylated N-terminal and a deletion of a His residue, as structural modifications. The secondary structure of LyeTxI-b is a well-defined helical segment, from the second amino acid to the amidated C-terminal, with no clear partition between hydrophobic and hydrophilic faces. Moreover, LyeTxI-b shows a potent antimicrobial activity against Gram-positive and Gram-negative planktonic bacteria, being 10-fold more active than the native peptide against Escherichia coli. LyeTxI-b was also active in an in vivo model of septic arthritis, reducing the number of bacteria load, the migration of immune cells, the level of IL-1ß cytokine and CXCL1 chemokine, as well as preventing cartilage damage. Our results show that LyeTxI-b is a potential therapeutic model for the development of new antibiotics against Gram-positive and Gram-negative bacteria.

The Peptide PnPP-19, a Spider Toxin Derivative, Activates µ-Opioid Receptors and Modulates Calcium Channels.

The synthetic peptide PnPP-19 comprehends 19 amino acid residues and it represents part of the primary structure of the toxin δ-CNTX-Pn1c (PnTx2-6), isolated from the venom of the spider Phoneutria nigriventer. Behavioural tests suggest that PnPP-19 induces antinociception by activation of CB1, µ and δ opioid receptors. Since the peripheral and central antinociception induced by PnPP-19 involves opioid activation, the aim of this work was to identify whether this synthetic peptide could directly activate opioid receptors and investigate the subtype selectivity for µ-, δ- and/or κ-opioid receptors. Furthermore, we also studied the modulation of calcium influx driven by PnPP-19 in dorsal root ganglion neurons, and analyzed whether this modulation was opioid-mediated. PnPP-19 selectively activates µ-opioid receptors inducing indirectly inhibition of calcium channels and hereby impairing calcium influx in dorsal root ganglion (DRG) neurons. Interestingly, notwithstanding the activation of opioid receptors, PnPP-19 does not induce ß-arrestin2 recruitment. PnPP-19 is the first spider toxin derivative that, among opioid receptors, selectively activates µ-opioid receptors. The lack of ß-arrestin2 recruitment highlights its potential for the design of new improved opioid agonists.

Electrophysiological Characterization of the Antarease Metalloprotease from Tityus serrulatus Venom.

Scorpions are among the oldest venomous living organisms and the family Buthidae is the largest and most medically relevant one. Scorpion venoms include many toxic peptides, but recently, a metalloprotease from Tityus serrulatus called antarease was reported to be capable of cleaving VAMP2, a protein involved in the neuroparalytic syndromes of tetanus and botulism. We have produced antarease and an inactive metalloprotease mutant in a recombinant form and analyzed their enzymatic activity on recombinant VAMP2 in vitro and on mammalian and insect neuromuscular junction. The purified recombinant antarease paralyzed the neuromuscular junctions of mice and of Drosophila melanogaster whilst the mutant was inactive. We were unable to demonstrate any cleavage of VAMP2 under conditions which leads to VAMP proteolysis by botulinum neurotoxin type B. Antarease caused a reduced release probability, mainly due to defects upstream of the synaptic vesicles fusion process. Paired pulse experiments indicate that antarease might proteolytically inactivate a voltage-gated calcium channel.

Brain Magnetic Stimulation in Animal Models: A Valuable Lesson for Clinical Applications.

Transcranial magnetic stimulation (TMS) is more than a mere tool for clinical non-invasive approaches to stimulate and synchronize the neuronal activity in the brain. Electromagnetic stimulation through TMS has recently emerged as a therapeutic alternative for the treatment of different neurological disorders. Among the many properties recently discovered for TMS, its action as an accounting factor for neuroplasticity and neurogenesis is among its most promising features. Translational studies in animal models offer various advantages and also bridge this knowledge gap due to their direct assessment of the brain stimulation impact at the neural level. These profiles have been obtained through the study of animal models, which, in turn, have served for the establishment of the action mechanisms of this method. In this review, we revise and discuss evidence collected on the promising properties of TMS after visiting the different animal models developed so far, and provide a practical perspective of its possible application for clinical purposes.

Expressed sequence tags in venomous tissue of Scorpaena plumieri (Scorpaeniformes: Scorpaenidae)

Species of the family Scorpaenidae are responsible for accidents and sporadic casualties by the shore they inhabit. The species Scorpaena plumieri from this family populate the Northeastern and Eastern coast of Brazil causing human envenomation characterized by local and systemic symptoms. In experimental animals the venom induces cardiotoxic, hypotensive, and airway respiratory effects. As first step to identify the venom components we isolated gland mRNA to produce a cDNA library from the fish gland. This report describes the partial sequencing of 356 gland transcripts from S. plumieri. BLAST analysis of transcripts showed that 30% were unknown sequences, 17% hypothetical proteins, 17% related to metabolic enzymes, 14% belonged to signal transducing functions and the remaining groups (7-8%) composed by gene related with expressing proteins, regulatory proteins and structural proteins. A considerable number of these EST were not found in available databases suggesting the existence of new proteins and/or functions yet to be discovered. By screening the library with antibodies against a lectin fraction from S. plumieri venom we identified several clones whose DNA sequence showed similarities with lectins found in fish. In silico analysis of these clones confirm the identity of these molecules in the venom gland of S. plumieri. .

Espécies da família Scorpaenidae são responsáveis por acidentes e mortes esporádicas ao longo da costa que habitam. A espécie Scorpaena plumieri desta família povoam a costa Leste e Nordeste do Brasil, causando envenenamento humano caracterizado por sintomas locais e sistêmicos. Em modelos experimentais animais a peçonha induz cardiotoxicidade, efeitos hipotensivos e alterações nas vias aéreas respiratórias. Como primeiro passo para identificar os componentes da peçonha foram isolados os mRNA das glândulas do peixe para produzir uma biblioteca de cDNAs. Esse artigo descreve o sequenciamento parcial de 356 transcritos das glândulas de S. plumieri. Análises em bancos de dados (BLAST) dos transcritos demonstraram que 30% eram sequências desconhecidas, 17% proteínas hipotéticas, 17% relacionadas às enzimas do metabolismo, 14% pertenciam a funções de transdução de sinais e os demais grupos (7-8%) formados por genes relacionados com a expressão de proteínas, proteínas regulatórias e estruturais. Um número considerável destes EST não foi encontrado em bases de dados disponíveis, sugerindo a existência de novas proteínas e/ou funções ainda a serem descobertas. Ao fazer um barrido da biblioteca com anticorpos produzidos contra uma fração das lectinas do veneno de S. plumieri, identificamos vários clones, cuja sequência de DNA mostram semelhanças com lectinas encontradas em peixes. A análise in silico destes clones confirmam a identidade destas moléculas na glândula de peçonha de S. plumieri.

Ilex paraguariensis Extract Increases Lifespan and Protects Against the Toxic Effects Caused by Paraquat in Caenorhabditis elegans.

Recent studies have shown that phenolic compounds present in yerba mate have antioxidant defense properties. To verify whether Ilex paraguariensis extracts are capable of increasing the lifespan of an organism, we have used the free-living nematode Caenorhabditis elegans. Notably, this is the first study that analyzes the effects of the extracts of yerba mate obtained from an extraction method that mimics the manner that the plant is consumed by the population by using a live organism. Yerba mate was purchased from commercial markets from Argentina, Brazil, and Uruguay. Ilex paraguariensis extracts significantly increased the life span of C. elegans. Moreover, the extracts reduced the ROS levels per se, and protected from the reduced survival and reproduction rate induced by paraquat exposure. Considering molecular aspects, we observed that the worms pretreated with the extracts depicted higher translocation of the transcription factor DAF-16::GFP to the nucleus. However, there was no increase in the levels of the DAF-16 target genes, SOD-3 and catalase. Our results suggest that the increase of lifespan caused by the different extracts is associated to the antioxidant potential of yerba mate, however this effect is not completely mediated by daf-16.

Asma na gravidez: atualização no manejo / Asthma in pregnancy: current management

A asma é doença crônica frequente na gestação, cujo descontrole encontra-se associado a desfechos maternos e perinatais desfavoráveis. O manejo da doença apresenta desafios, tais como a resistência das pacientes em utilizar medicações durante a gravidez, além de queixas frequentes de dispneia associada ao estado gravídico, não relacionada à asma. O objetivo do presente trabalho foi revisar os conhecimentos atuais sobre asma na gravidez. As fontes de dados foram revisões e artigos originais publicados nos últimos 12 anos e indexados nas bases de dados PubMed, SciELO e Lilacs. As conclusões deste artigo de revisão indicam que o controle adequado da asma juntamente com a vigilância obstétrica cuidadosa devem ser integrados e constituir objetivo global do tratamento de gestantes asmáticas. O tratamento medicamentoso permite o uso de algumas medicações utilizadas em pacientes não gestantes.

Asthma is a common chronic disease during pregnancy, and inappropriate control of this conditionis associated with unfavorable maternal and perinatal outcomes. Management of asthma duringpregnancy presents challenges, including the patients’ resistance to use medications duringpregnancy and frequent complaints of dyspnea associated with pregnancy but not related toasthma. The objective of the present study was to review the current knowledge about asthmain pregnancy. Data sources included reviews and original articles published in the past 12 yearsand indexed in PubMed, SciELO, and Lilacs databases. Our findings indicate that adequate controlof asthma and careful obstetric follow-up should be integrated and constitute a global goal intreating pregnant women with asthma. Pharmacologic treatment allows for the use of somemedications that are used in non-pregnant patients.

New insights on arthropod toxins that potentiate erectile function.

The use of natural substances for the treatment of diseases or injuries is an ancient practice of many cultures. According to folklore, natural aphrodisiacs may help to raise libido and increase desire. The supposed aphrodisiacs mainly include a plethora of preparations of plants, among other substances. However, the real boundary between myth and reality has not been established yet in most cases and such boundaries must be drawn by scientific methods. A growing interest of the scientific community has been focused on animal venoms, especially those from arthropods, i.e. spiders and scorpions, which cause priapism, a prolonged and painful erection. This review highlights the studies that have been performed with venoms and toxins from arthropods known to cause priapism, among other toxic symptoms, pointing out some pharmacological approaches for better understanding this effect. To date, the venom of some spiders, mainly Phoneutria nigriventer, and scorpions, such as the yellow South American scorpion Tityus serrulatus, among others, have been known to cause priapism. Since erectile dysfunction (ED) is a growing health problem in the world, more common in patients with vascular diseases as diabetes and hypertension, the use of animal venoms and toxins as pharmacological tools could not only shed light to the mechanisms involved in erectile function, but also represent a possible model for new drugs to treat ED. Unfortunately, attempts to correlate the structure of those priapism-related toxins were unfruitful. Such difficulties lie firstly on the poor data concerning purified priapism-related toxins, instead of whole venoms and/or semi-purified fractions, and secondly, on the scarce available primary sequences and structural data, mainly from spider toxins. It has been shown that all these toxins modify the sodium (Na(+)) channel activity, mostly slowing down its inactivation current. Improving the knowledge on the tertiary structure of these toxins could provide a key in the search of a new drug for ED treatment.

Purification of a lectin from the marine red alga Gracilaria cornea and its effects on the cattle tick Boophilus microplus (Acari: Ixodidae).

A lectin was purified from the seaweed Gracilaria cornea by hydrophobic interaction chromatography on phenyl-Sepharose CL-4B followed by affinity chromatography on immobilized mucin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of G. cornea lectin (GCL) revealed a single protein band of approximately 60 kDa, whereas by gel filtration on Sephadex G-100 its native molecular mass was 66 kDa. GCL exhibited a single isoeletric point of 4.3 and a 52.5% content of neutral sugars. Furthermore, the EDTA-treated lectin did not show any significant decrease in its ability to agglutinate trypsin-treated chicken erythrocytes. These data suggest that GCL is an acidic, monomeric glycoprotein that probably does not require divalent metal ions for its hemagglutinating activity. GCL hemagglutinating activity was not inhibited by any of the mono-, di-, and trisaccharides tested but was by the complex glycoproteins fetuin and porcine stomach mucin. Exposure of engorged females of the cattle tick (Boophilus microplus) to 0.1 mg mL(-1) GCL significantly (P < 0.05) reduced the female weight after the oviposition period, the egg mass weight, the hatching period, and the mean larvae survival time.

Implementación de un programa de control y seguimiento de las embarazadas desde el servicio de medicina transfusional. Primera etapa / First step in implementation of a control and follow-up programme of pregnant women performed by a transfusional medicine service

Nuestro programa de control y seguimiento de la mujer embarazada se basó en el diagnóstico previo realizado desde el SMT. Los objetivos fueron: disminuir el índice transfusional, uso adecuado de hemocomponentes, EIH de la embarazada, control de anemias, aumentar las interconsultas con nuestro Servicio, cubrir la mayor parte de los ingresos a cesárea o parto con EIH mínimo, que brindará una mayor seguridad transfusional. Desde enero de 1999 a diciembre de 2001 ingresaron a la institución 9.065 pacientes ginecoobstétricas, de las cuales 2.722 (31,80 por ciento) fueron estudiadas por el SMT antes de ingresar a parto o cesárea. Se les realizó HC, EIH (grupo, factor Rh, detección e identificación de anticuerpos irregulares, compatibilidad). Se detectaron: 16,33 por ciento de pacientes con antecedentes de riesgo de sensibilización; de éstas, el 4,99 por ciento presentaba uno o más anticuerpos de importancia clínica; discrepancias ABO 3,93 por ciento y Rh 1,47 por ciento. El porcentaje de interconsultas con el SMT fue del 3,40 por ciento durante el embarazo para EIH, control y tratamiento de anemias. Al implementar formularios de solicitud de transfusión encontramos que el 52,15 por ciento de las solicitudes de transfusiones (no generadas como interconsulta con el SMT) eran con carácter de urgencia o emergencia. Del 100 por ciento de las transfusiones realizadas, el 62,64 por ciento fue por interconsulta con el SMT; esto, junto con la presencia permanente del Servicio, permitió lograr un uso adecuado de hemocomponentes en el 100 por ciento de los casos. El porcentaje de pacientes transfundidas disminuyó del 8,56 por ciento al 6,17 por ciento. (AU)

Implementación de un programa de control y seguimiento de las embarazadas desde el servicio de medicina transfusional. Primera etapa / First step in implementation of a control and follow-up programme of pregnant women performed by a transfusional medicine service

Nuestro programa de control y seguimiento de la mujer embarazada se basó en el diagnóstico previo realizado desde el SMT. Los objetivos fueron: disminuir el índice transfusional, uso adecuado de hemocomponentes, EIH de la embarazada, control de anemias, aumentar las interconsultas con nuestro Servicio, cubrir la mayor parte de los ingresos a cesárea o parto con EIH mínimo, que brindará una mayor seguridad transfusional. Desde enero de 1999 a diciembre de 2001 ingresaron a la institución 9.065 pacientes ginecoobstétricas, de las cuales 2.722 (31,80 por ciento) fueron estudiadas por el SMT antes de ingresar a parto o cesárea. Se les realizó HC, EIH (grupo, factor Rh, detección e identificación de anticuerpos irregulares, compatibilidad). Se detectaron: 16,33 por ciento de pacientes con antecedentes de riesgo de sensibilización; de éstas, el 4,99 por ciento presentaba uno o más anticuerpos de importancia clínica; discrepancias ABO 3,93 por ciento y Rh 1,47 por ciento. El porcentaje de interconsultas con el SMT fue del 3,40 por ciento durante el embarazo para EIH, control y tratamiento de anemias. Al implementar formularios de solicitud de transfusión encontramos que el 52,15 por ciento de las solicitudes de transfusiones (no generadas como interconsulta con el SMT) eran con carácter de urgencia o emergencia. Del 100 por ciento de las transfusiones realizadas, el 62,64 por ciento fue por interconsulta con el SMT; esto, junto con la presencia permanente del Servicio, permitió lograr un uso adecuado de hemocomponentes en el 100 por ciento de los casos. El porcentaje de pacientes transfundidas disminuyó del 8,56 por ciento al 6,17 por ciento.

Disgenesia multiquística renal: presentación de un caso / Renal polycystic dysgenesis: report of a case

Se presentan los resultados del estudio necrópsico realizado a un recién nacido del sexo masculino, con una enfermedad quística renal diagnosticada como disgenesia multiquística. Se expone la descripción anatómica de los riñones y malformaciones congénitas asociadas al nivel del corazón, tronco arterial aortopulmonar, pulmones, tracto gastrointestinal, bazo, testículo y pene. Para ello nos auxiliamos de los resultados del estudio histológico de las vísceras. Realizamos una breve discusión a manera de comentario de la patogénesis multiquística renal y las malformaciones congénitas asociadas

Disgenesia multiquística renal: presentación de un caso / Renal polycystic dysgenesis: report of a case

Se presentan los resultados del estudio necrópsico realizado a un recién nacido del sexo masculino, con una enfermedad quística renal diagnosticada como disgenesia multiquística. Se expone la descripción anatómica de los riñones y malformaciones congénitas asociadas al nivel del corazón, tronco arterial aortopulmonar, pulmones, tracto gastrointestinal, bazo, testículo y pene. Para ello nos auxiliamos de los resultados del estudio histológico de las vísceras. Realizamos una breve discusión a manera de comentario de la patogénesis multiquística renal y las malformaciones congénitas asociadas