226 research outputs found
Conservación del patrimonio farmacéutico de herencia española en Puerto Rico, 100 años después
En este trabajo se examina el patrimonio farmacéutico español que subiste en Puerto Rico, después de más de 100 años de terminada la soberanía española. A la luz de la legislación existente y de las colecciones que se exhiben en tres museos, se hace evidente que los 405 años de las Institucionalidad española en la Isla dejó una huella que sigue formando parte de la vida cotidiana de los puertorriqueños del siglo XXI
Double-Stranded RNA Technology to Control Insect Pests: Current Status and Challenges
Exploiting the RNA interference (RNAi) gene mechanism to silence essential genes in pest insects, leading to toxic effects, has surfaced as a promising new control strategy in the past decade. While the first commercial RNAi-based products are currently coming to market, the application against a wide range of insect species is still hindered by a number of challenges. In this review, we discuss the current status of these RNAi- based products and the different delivery strategies by which insects can be targeted by the RNAi-triggering double-stranded RNA (dsRNA) molecules. Furthermore, this review also addresses a number of physiological and cellular barriers, which can lead to decreased RNAi efficacy in insects. Finally, novel non-transgenic delivery technologies, such as polymer or liposomic nanoparticles, peptide-based delivery vehicles and viral- like particles, are also discussed, as these could overcome these barriers and lead to effective RNAi-based pest control
Draft genome sequence of Xanthomonas arboricola pv. pruni strain Xap33, causal agent of bacterial spot disease on almond
We report the annotated genome sequence of Xanthomonas arboricola pv. pruni strain Xap33, isolated from almond leaves showing bacterial spot disease symptoms in Spain. The availability of this genome sequence will aid our understanding of the infection mechanism of this bacterium as well as its relationship to other species of the same genus.Publishe
Diabrotica undecimpunctata virus 2, a Novel Small RNA Virus Discovered from Southern Corn Rootworm, Diabrotica undecimpunctata howardi Barber (Coleoptera: Chrysomelidae)
The genome of Diabrotica undecimpunctata virus 2 (DuV2), a positive-sense, single-stranded RNA virus identified from the southern corn root- worm transcriptome, comprises 5,313 nucleotides, including a short poly(A) tail. The two open reading frames encode a nonstructural polyprotein (p156) and a putative capsid protein (p25)
Pyrethroid Exposure Reduces Growth and Development of Monarch Butterfly (Lepidoptera: Nymphalidae) Caterpillars
Insecticide exposure has been identified as a contributing stressor to the decline in the North American monarch butterfly Danaus plexippus L. (Lepidoptera: Nymphalidae) population. Monarch toxicity data are currently limited and available data focuses on lethal endpoints. This study examined the 72-h toxicity of two pyrethroid insecticides, bifenthrin and β-cyfluthrin, and their effects on growth and diet consumption. The toxicity of bifenthrin to caterpillars was lower than β-cyfluthrin after 72 h. Survival was the most sensitive endpoint for bifenthrin, but diet consumption and caterpillar growth were significantly reduced at sublethal levels of β-cyfluthrin. Using AgDRIFT spray drift assessment, the aerial application of bifenthrin or β-cyfluthrin is predicted to pose the greatest risk to fifth-instar caterpillars, with lethal insecticide deposition up to 28 m for bifenthrin and up to 23 m for β-cyfluthrin from treated edges of fields. Low boom ground applications are predicted to reduce distances of lethal insecticide exposure to 2 m from the treated field edge for bifenthrin and β-cyfluthrin. Growth and survival of fifth-instar monarch caterpillars developing within the margins of a treated field may be significantly impacted following foliar applications of bifenthrin or β-cyfluthrin. These findings provide evidence that pyrethroid insecticides commonly used for soybean pest control are a potential risk to monarch caterpillars in agricultural landscapes
Genome Sequence of a Small RNA Virus of the Southern Corn Rootworm, Diabrotica undecimpunctata howardi Barber (Coleoptera: Chrysomelidae)
The genome sequence of a novel small RNA virus, tentatively named Diabrotica undecimpunctata virus 1 (DuV1), was discovered from the transcriptome of the southern corn rootworm, Diabrotica undecimpunctata howardi Barber. DuV1 has a positive-sense, single-stranded RNA genome that encodes a single polyprotein of 3,401 amino acids with limited similarity to other viruses
Cardenolide, Potassium, and Pyrethroid Insecticide Combinations Reduce Growth and Survival of Monarch Butterfly Caterpillars (Lepidoptera: Nymphalidae)
The monarch butterfly, Danaus plexippus L., has evolved to be insensitive to milkweed cardenolides via genetic modifications of Na+/K+-ATPase. There is concern for insecticide exposures near agriculture, with little information on monarch caterpillar toxicology. It is unclear how cardenolide insensitivity may affect the sensitivity of monarch caterpillars to pyrethroid insecticides. Additionally, potassium fertilizers may affect monarch caterpillar physiology and cardenolide sequestration. Here, we investigated the growth, survival, and development of caterpillars exposed to the cardenolide ouabain, bifenthrin, and potassium chloride (KCl) alone and in combination. Caterpillars were either exposed to (1) ouabain from third- to fifth-instar stage, (2) KCl at fifth-instar stage, (3) KCl and bifenthrin at fifth-instar stage, or (4) combinations of ouabain at third-instar stage + KCl + bifenthrin at fifth-instar stage. Caterpillar weight, diet consumption, frass, and survival were recorded for the duration of the experiments. It was observed that 1–3 mg ouabain/g diet increased body weight and diet consumption, whereas 50 mg KCl/g diet decreased body weight and diet consumption. Caterpillars feeding on KCl and treated with 0.2 μg/μl bifenthrin consumed significantly less diet compared to individuals provided untreated diet. However, there was no effect on survival or body weight. Combinations of KCl + ouabain did not significantly affect caterpillar survival or body weight following treatment with 0.1 μg/μl bifenthrin. At the concentrations tested, there were no effects observed for bifenthrin sensitivity with increasing cardenolide or KCl concentrations. Further studies are warranted to understand how milkweed-specific cardenolides, at increasing concentrations, and agrochemical inputs can affect monarch caterpillar physiology near agricultural landscapes
Sequela fibrótica na paracoccidioidomicose pulmonar: aspectos histopatológicos em camundongos BALB/c infectados com propágulos viáveis e não viáveis do Paracoccidioides brasiliensis
Patients with paracoccidioidomycosis often present pulmonary fibrosis and exhibit important respiratory limitations. Based on an already established animal model, the contribution of viable and non-viable P. brasiliensis propagules to the development of fibrosis was investigated. BALB/c male mice, 4-6 weeks old were inoculated intranasally either with 4x10(6 )viable conidia (Group I), or 6.5x10(6) fragmented yeast cells (Group II). Control animals received PBS. Six mice per period were sacrificed at 24, 48, 72h (initial) and 1, 2, 4, 8, 12 and 16 weeks post-challenge (late). Paraffin embedded lungs were sectioned and stained with H&E, trichromic (Masson), reticulin and Grocott´s. During the initial period PMNs influx was important in both groups and acute inflammation involving 34% to 45% of the lungs was noticed. Later on, mononuclear cells predominated. In group I, the inflammation progressed and granulomas were formed and by the 12th week they fussed and became loose. Thick collagen I fibers were observed in 66.6% and 83.3% of the animals at 8 and 12 weeks, respectively. Collagen III, thick fibers became apparent in some animals at 4weeks and by 12 weeks, 83% of them exhibited alterations in the organization and thickness of these elements. In group II mice, this pattern was different with stepwise decrease in the number of inflammatory foci and lack of granulomas. Although initially most animals in this group had minor alterations in thin collagen I fibers, they disappeared by the 4th week. Results indicate that tissue response to fragmented yeast cells was transitory while viable conidia evoked a progressive inflammatory reaction leading to granuloma formation and to excess production and/or disarrangement of collagens I and III; the latter led to fibrosis.Pacientes com paracoccidioidomicose apresentam, algumas vezes, fibrose pulmonar e exibem limitações respiratórias importantes. Baseados num modelo animal já estabelecido da micose, estudamos a possível contribuição de propágulos viáveis e não viáveis do Paracoccidioides brasiliensis ao desenvolvimento da fibrose. Assim, camundongos BALB/c, machos de 4 a 6 semanas de idade, foram inoculados intranasalmente com 4 x 10(6) conídios viáveis (Grupo I), ou com 6,5 x 10(6) fragmentos não viáveis de células leveduriformes (Grupo II). Animais controles (Grupo III) receberam unicamente PBS. Seis camundongos por período foram sacrificados 24, 48, 72h (inicial) e 1, 2, 4, 8, 12 e 16 semanas pós-inoculação (tardio). Os pulmões dos animais foram fixados, incluidos em parafina, cortados e corados com H & E, Tricrômico (Masson), reticulina e Grocott. Durante o período inicial houve afluxo importante de PMNs em ambos os grupos I e II, e a inflamação aguda comprometeu entre 34 a 45% dos pulmões. Depois, foram as células mononucleares as que predominaram. No grupo I, a inflamação progrediu e formaram-se granulomas os quais, às 12 semanas, ficaram confluentes e frouxos. Adicionalmente, se observaram fibras de colágeno tipo I muito densas em 66,6% e 83,3% dos animais após 8 e 12 semanas, respectivamente. As fibras do colágeno tipo III foram observadas nos animais a partir das 4 semanas pós-infecção, e 83% deles exibiram, às 12 semanas, alterações na sua distribuição e organização. Nos animais do grupo II o padrão foi diferente, pois mostraram diminuição gradual no número de focos inflamatórios e não houve formação dos granulomas. Embora animais deste grupo tivessem no período inicial pequenas alterações nas fibras de colágeno tipo I, estas desapareceram por volta da 4a semana. Os resultados indicam que a resposta tissular aos fragmentos de leveduras foi transitória, enquanto que os conídios induzem resposta inflamatória progressiva permitindo a formação de granuloma e um excesso na produção e desorganização dos colágenos I e III, permitindo finalmente a fibrose
Diseño y control de filtros activos mediante simulación HIL
La implementación de los filtros activos es una de las soluciones más eficientes a la
problemática que plantea el creciente uso de cargas no lineales en la red eléctrica
y la proliferación de cargas distribuidas provenientes de energías renovables
conectadas a la misma. El diseño de un filtro activo y del algoritmo para su control
pueden realizarse mediante la simulación “Hardware in the loop” (HIL) en tiempo
real. Estas simulaciones sirven de interfaz entre el modelo matemático de todos los
elementos dinámicos relacionados con el sistema eléctrico bajo control (simulación
de la planta) y el sistema integrado bajo prueba. En este trabajo se ha desarrollado
la simulación en la máquina virtual de Typhoon HIL, tanto del modelo del filtro
activo como de su algoritmo de control. Tras la comprobación de los modelos se
ha implementado el algoritmo en una tarjeta de procesamiento digital (DSP). Para
la elaboración del código de programación necesario en este sistema de control de
prueba se incorporan las herramientas Simulink de Matlab y Code Composer Studio
(CCS). Los resultados han sido satisfactorios en general y ofrecen la posibilidad de la
implementación física del sistema propuesto con un coste reducido.Active Power Filter implementation is one of the most efficient solutions for problems
which raises non-linear loads in the electric net and proliferation of the distributed
charges which are coming from the connection of renewable energy sources. The
active filter design and its control algorithm can do with the real time simulation
“Hardware in the loop” (HIL). These simulations work as interface between the
mathematician model of all dynamic elements, which relate to the under control
electric system, and the integrated system which is under test. In this project, the
simulation in the virtual machine of Typhoon HIL has been developed, including the
filter active model and its control algorithm. After checking the model, the algorithm
has been implanted in a digital signal processor card. To write the necessary
programming code in this embedded system under test, Simulink of Matlab and
Code Composer Studio tools are used. In general, results have been satisfactory, so
the designed model give us the chance of implementing physically the system with
a reduced price
Reconstitution of respiratory complex I on a biomimetic membrane supported on gold electrodes
For the first time, respiratory complex I has been reconstituted on an electrode preserving its structure and activity. Respiratory complex I is a membrane-bound enzyme that has an essential function in cellular energy production. It couples NADH:quinone oxidoreduction to translocation of ions across the cellular (in prokaryotes) or mitochondrial membranes. Therefore, complex I contributes to the establishment and maintenance of the transmembrane difference of electrochemical potential required for adenosine triphosphate synthesis, transport, and motility. Our new strategy has been applied for reconstituting the bacterial complex I from Rhodothermus marinus onto a biomimetic membrane supported on gold electrodes modified with a thiol self-assembled monolayer (SAM). Atomic force microscopy and faradaic impedance measurements give evidence of the biomimetic construction, whereas electrochemical measurements show its functionality. Both electron transfer and proton translocation by respiratory complex I were monitored, simulating in vivo conditions. © 2014 American Chemical Society.This work was funded by the Spanish MINECO (project CTQ2012-32448) and by Fundação para a Ciência e a Tecnologia (PTDC/BBB-BQB/2294/2012 to M.M.P.). The work was also supported by Fundação para a Ciência e a Tecnologia through grant # PEst-OE/EQB/LA0004/2011. M.P. and O.G.-S. acknowledge the Ramon y Cajal and the FPI programs respectively from the Spanish MINECO. A.P.B. is recipient of a grant from Fundação para a Ciência e a Tecnologia (SFRH/BPD/80741/2011).Peer Reviewe
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