RESUMEN
Parapanteles Ashmead (Braconidae: Microgastrinae) is a medium-sized genus of microgastrine wasps that was erected over a century ago and lacks a unique synapomorphic character, and its monophyly has not been tested by any means. Parapanteles usually are parasitoids of large, unconcealed caterpillars (macrolepidoptera) and have been reared from an unusually large diversity of hosts for a relatively small microgastrine genus. We used Cytochrome Oxidase I sequences ("DNA barcodes") available for Parapanteles and other microgastrines to sample the generic diversity of described and undescribed species currently placed in Parapanteles, and then sequenced four additional genes for this subsample (wingless, elongation factor 1-alpha, ribosomal subunit 28s, and NADH dehydrogenase subunit 1). We constructed individual gene trees and concatenated Bayesian and maximum-likelihood phylogenies for this 5-gene subsample. In these phylogenies, most Parapanteles species formed a monophyletic clade within another genus, Dolichogenidea, while the remaining Parapanteles species were recovered polyphyletically within several other genera. The latter likely represent misidentified members of other morphologically similar genera. Species in the monophyletic clade containing most Parapanteles parasitized caterpillars from only five families - Erebidae (Arctiinae), Geometridae, Saturniidae, Notodontidae, and Crambidae. We do not make any formal taxonomic decisions here because we were not able to include representatives of type species for Parapanteles or other relevant genera, and because we feel such decisions should be reserved until a comprehensive morphological analysis of the boundaries of these genera is accomplished.
Asunto(s)
Himenópteros/clasificación , Animales , Teorema de Bayes , Complejo IV de Transporte de Electrones/clasificación , Complejo IV de Transporte de Electrones/genética , Himenópteros/genética , Proteínas de Insectos/clasificación , Proteínas de Insectos/genética , NADH Deshidrogenasa/clasificación , NADH Deshidrogenasa/genética , Filogenia , ARN Ribosómico 28S/clasificación , ARN Ribosómico 28S/genéticaRESUMEN
This Article has been retracted; see accompanying Retraction Note.
RESUMEN
Antisense oligonucleotide (ASO) silencing of the expression of disease-associated genes is an attractive novel therapeutic approach, but treatments are limited by the ability to deliver ASOs to cells and tissues. Following systemic administration, ASOs preferentially accumulate in liver and kidney. Among the cell types refractory to ASO uptake is the pancreatic insulin-secreting ß-cell. Here, we show that conjugation of ASOs to a ligand of the glucagon-like peptide-1 receptor (GLP1R) can productively deliver ASO cargo to pancreatic ß-cells both in vitro and in vivo. Ligand-conjugated ASOs silenced target genes in pancreatic islets at doses that did not affect target gene expression in liver or other tissues, indicating enhanced tissue and cell type specificity. This finding has potential to broaden the use of ASO technology, opening up novel therapeutic opportunities, and presents an innovative approach for targeted delivery of ASOs to additional cell types.
Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Oligonucleótidos Antisentido/administración & dosificación , Animales , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Silenciador del Gen , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/genética , Células HEK293 , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Oligonucleótidos Antisentido/química , Oligonucleótidos Antisentido/farmacocinética , ARN Largo no Codificante/genéticaRESUMEN
Platinum drugs are the frontline therapy in many carcinomas, including high-grade serous ovarian cancers. Clinically, high-grade serous carcinomas have an apparent complete response to carboplatin, but tumors invariably recur and response to platinum drugs diminishes over time. Standard of care prohibits re-administration of platinum drugs to these patients who are labeled as having platinum-resistant disease. In this stage patients are treated with non-platinum agents and outcomes are often poor. In vivo and in vitro data presented here demonstrate that this clinical dogma should be challenged. Platinum drugs can be an effective therapy even for platinum-resistant carcinomas as long as they are combined with an agent that specifically targets mechanisms of platinum resistance exploited by the therapy-resistant tumor subpopulations. High levels of cellular inhibitor of apoptosis proteins cIAP1 and 2 (cIAP) were detected in up to 50% of high-grade serous and non-high-grade serous platinum-resistant carcinomas. cIAP proteins can induce platinum resistance and they are effectively degraded with the drug birinapant. In platinum-resistant tumors with ≥22.4 ng of cIAP per 20 µg of tumor lysate, the combination of birinapant with carboplatin was effective in eliminating the cancer. Our findings provide a new personalized therapeutic option for patients with platinum-resistant carcinomas. The efficacy of birinapant in combination with carboplatin should be tested in high-grade serous carcinoma patients in a clinical trial.
RESUMEN
High-grade serous ovarian cancers (HGSCs) are deadly malignancies that relapse despite carboplatin chemotherapy. Here we show that 16 independent primary HGSC samples contain a CA125-negative population enriched for carboplatin-resistant cancer initiating cells. Transcriptome analysis reveals upregulation of homologous recombination DNA repair and anti-apoptotic signals in this population. While treatment with carboplatin enriches for CA125-negative cells, co-treatment with carboplatin and birinapant eliminates these cells in HGSCs expressing high levels of the inhibitor of apoptosis protein cIAP in the CA125-negative population. Birinapant sensitizes CA125-negative cells to carboplatin by mediating degradation of cIAP causing cleavage of caspase 8 and restoration of apoptosis. This co-therapy significantly improves disease-free survival in vivo compared with either therapy alone in tumour-bearing mice. These findings suggest that therapeutic strategies that target CA125-negative cells may be useful in the treatment of HGSC.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Carboplatino/farmacología , Dipéptidos/farmacología , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/genética , Indoles/farmacología , Proteínas Inhibidoras de la Apoptosis/efectos de los fármacos , Neoplasias Quísticas, Mucinosas y Serosas/genética , Neoplasias Ováricas/genética , Animales , Apoptosis/genética , Antígeno Ca-125/metabolismo , Caspasa 8/efectos de los fármacos , Caspasa 8/metabolismo , Femenino , Perfilación de la Expresión Génica , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Trasplante de Neoplasias , Neoplasias Quísticas, Mucinosas y Serosas/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Reparación del ADN por Recombinación/genética , Regulación hacia ArribaRESUMEN
Recent studies on the molecular determinants important for glycine receptor biogenesis and function mechanisms indicate an important role of basic residues within the intracellular loop between transmembrane domains (TM) 3 and 4. We investigate the role of loop length and loop exchange in combination with the presence or absence of basic stretches (318)RRKRR and (385)KKIDK of the human glycine receptor α1 using expression in transfected cell lines. Exchanges of the large intracellular loop between members of the Cys-loop receptor family have been shown to keep functionality of the host receptor. Here, constructs were generated with deletion of the intracellular loop of the glycine receptor α1, insertion of the loop from the prokaryotic Cys-loop receptor of Gloeobacter violaceus both with and without leaving the basic stretches at the N-terminal and C-terminal part of the intracellular domain. All receptor constructs were expressed at the cell surface with the significantly lowest expression of the construct with a deletion of the glycine receptor α1 TM3-4 loop, except the two basic stretches adjoined. Functionality of the inhibitory glycine receptor chimeras was demonstrated with whole cell recordings from transfected cells. Chimeras lacking the basic stretches result in non-functionality. An analysis of receptor desensitization demonstrated that close proximity of both basic stretches resulted in large fractions of desensitizing currents. We conclude that the TM3-4 loop length is critical for glycine receptor α1 desensitization and a direct neighborhood of both basic stretches changes receptor properties from non-desensitizing to desensitizing.
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Receptores de Glicina/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Cianobacterias/metabolismo , Células HEK293 , Humanos , Datos de Secuencia Molecular , Mutación , Receptores de Glicina/química , Receptores de Glicina/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
Reaction of [9]aneS3 (1,4,7-trithiacyclononane) with KAuCl4 in nitromethane yields the complex [Au([9]aneS3)Cl2][AuCl4]. Heating of this salt yields the bicyclic sulfonium [9]aneS3(+) (4,7-dithia-1-thioniabicyclo[4,3,0]nonane) as a racemic [AuCl4](-) salt. Further reaction produces [[9]aneS3(+)][AuCl2], which undergoes spontaneous resolution upon crystallization. Each enantiomer of [[9]aneS3(+)][AuCl2] was crystallographically characterized as well as the racemic [AuCl4](-) salt.
RESUMEN
Microgastrine wasps are among the most species-rich and numerous parasitoids of caterpillars (Lepidoptera). They are often host-specific and thus are extensively used in biological control efforts and figure prominently in trophic webs. However, their extraordinary diversity coupled with the occurrence of many cryptic species produces a significant taxonomic impediment. We present and release the results of 8 years (2004-2011) of DNA barcoding microgastrine wasps. Currently they are the best represented group of parasitoid Hymenoptera in the Barcode of Life Data System (BOLD), a massive barcode storage and analysis data management site for the International Barcoding of Life (iBOL) program. There are records from more than 20 000 specimens from 75 countries, including 50 genera (90% of the known total) and more than 1700 species (as indicated by Barcode Index Numbers and 2% MOTU). We briefly discuss the importance of this DNA data set and its collateral information for future research in: (1) discovery of cryptic species and description of new taxa; (2) estimating species numbers in biodiversity inventories; (3) clarification of generic boundaries; (4) biological control programmes; (5) molecular studies of host-parasitoid biology and ecology; (6) evaluation of shifts in species distribution and phenology; and (7) fostering collaboration at national, regional and world levels. The integration of DNA barcoding with traditional morphology-based taxonomy, host records, and other data has substantially improved the accuracy of microgastrine wasp identifications and will significantly accelerate further studies on this group of parasitoids.
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Código de Barras del ADN Taxonómico , Filogenia , Avispas/clasificación , Avispas/genética , Animales , Secuencia de Bases , Datos de Secuencia Molecular , Análisis de Secuencia de ADNRESUMEN
Within butterflies and moths, adult hematophagy is limited to species within the vampire moth genus Calyptra. These moths are placed within the subfamily Calpinae, whose other members are known to exhibit a broad range of feeding behaviors including those that can be considered 'piercers' of fruits or other hosts and 'tear feeders'. Here, we reconstruct a phylogenetic hypothesis of Calpinae using molecular data to test whether hematophagy in Calyptra arose from plant or animal-related behaviors. We use a Bayesian method of ancestral state reconstruction to determine the most likely feeding behaviors for the subtribes and genera within this lineage.
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Conducta Alimentaria , Mariposas Nocturnas/clasificación , Filogenia , Animales , Teorema de Bayes , Núcleo Celular/genética , ADN Mitocondrial/genética , Frutas , Genes de Insecto , Funciones de Verosimilitud , Modelos Genéticos , Mariposas Nocturnas/genéticaRESUMEN
Insect outbreaks are expected to increase in frequency and intensity with projected changes in global climate through direct effects of climate change on insect populations and through disruption of community interactions. Although there is much concern about mean changes in global climate, the impact of climatic variability itself on species interactions has been little explored. Here, we compare caterpillar-parasitoid interactions across a broad gradient of climatic variability and find that the combined data in 15 geographically dispersed databases show a decrease in levels of parasitism as climatic variability increases. The dominant contribution to this pattern by relatively specialized parasitoid wasps suggests that climatic variability impairs the ability of parasitoids to track host populations. Given the important role of parasitoids in regulating insect herbivore populations in natural and managed systems, we predict an increase in the frequency and intensity of herbivore outbreaks through a disruption of enemy-herbivore dynamics as climates become more variable.
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Efecto Invernadero , Lepidópteros/parasitología , Avispas/fisiología , Animales , Geografía , Interacciones Huésped-Parásitos , Larva/parasitología , Larva/fisiología , Lepidópteros/fisiología , Dinámica Poblacional , Análisis de RegresiónRESUMEN
We report a convenient synthesis of K(2)[Ru(bpy)(NO(2))(4)] via the thermal displacement of benzene from [(Bz)Ru(bpy)Cl]Cl (Bz = eta(6)-C(6)H(6); bpy = 2,2'-bipyridine) by nitrite ion in methanol solution. K(2)[Ru(bpy)(NO(2))(4)] has been fully characterized by elemental analysis, X-ray crystallography, and (1)H NMR, IR, UV-vis, and emission spectroscopy. Reaction of K(2)[Ru(bpy)(NO(2))(4)] with pyridine under mild or forcing conditions produces fac-K[Ru(bpy)(NO(2))(3)(py)] and cis-[Ru(NO(2))(2)(bpy)(py)(2)] (py = pyridine), respectively. We report full characterization data for these compounds, including crystal structures. The d pi(Ru) --> pi*(bpy) charge-transfer band in the electronic spectra of K(2)[Ru(bpy)(NO(2))(4)] and fac-[Ru(bpy)(NO(2))(3)(py)] displays a significant solvent dependence. The energy of the absorption band correlates linearly with the Gutmann solvent acceptor number. The solvatochromic response of these nitro complexes is essentially identical to that of the analogous cyanide complexes, indicating that the mechanism previously proposed to explain the solvatochromism of the cyanide complexes may need to be reexamined.
RESUMEN
OBJECTIVE: To quantify image artifact reduction using a new technique (MARS--metal artifact reduction sequence) in vitro. DESIGN: Coronal T1-weighted MR images were obtained through two metal phantoms (titanium/chromium-cobalt and stainless steel femoral prostheses) immersed in water. Comparison of artifact volume was made with images obtained using conventional and modified (MARS) T1-weighted sequences. Signal intensity values outside a range of +/-40% the average signal intensity for water were considered artifact and segmented into low or high signal artifact categories. Considering the arbitrary selection of this threshold value, volumetric calculations of artifact were also evaluated at +/-50%, 60%, 70%, and 80% the mean signal for water. RESULTS: Conventional T1-weighted images produced 87% more low signal artifact and 212% more high signal artifact compared with the MARS modified T1-weighted images of the stainless steel prosthesis. Conventional T1-weighted images of the titanium prosthesis produced 84% more low signal artifact and 211% more high signal artifact than the MARS modified sequence. The level of artifact reduction was essentially uniform for the various threshold levels tested and was greatest at +/-20% the global signal intensity average for water. CONCLUSION: The MARS technique reduces the volume of image signal artifact produced by stainless steel and titanium/chromium-cobalt femoral prostheses on T1-weighted spin-echo images in a tissue phantom model.
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Artefactos , Imagen por Resonancia Magnética/métodos , Metales , Cromo , Cobalto , Prótesis de Cadera , Humanos , Imagen por Resonancia Magnética/instrumentación , Fantasmas de Imagen , Prótesis e Implantes , Acero Inoxidable , TitanioRESUMEN
OBJECTIVE: This study was designed to compare diagnostic quality of MR images of patients with spinal hardware acquired using a conventional T1-weighted spin-echo sequence and a new metal artifact reduction sequence (MARS). CONCLUSION: The new MARS sequence effectively reduces the degree of tissue-obscuring artifact produced by spinal fixation hardware and subjectively improves image quality compared with the conventional T1-weighted spin-echo sequence.
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Artefactos , Fijadores Internos , Imagen por Resonancia Magnética/métodos , Columna Vertebral/patología , Columna Vertebral/cirugía , Adulto , Anciano , Humanos , Masculino , Metales , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Three new asexual yeast species were isolated from various floricolous insects. Candida cleridarum sp. nov. was the dominant species in clerid beetles collected in flowers of various cacti in Arizona and Southern California. The sequence of the D1D2 domains of the large-subunit rDNA showed that it is a sister species to Candida fragi (0.9% base difference), a yeast isolated once from fermenting strawberries. Candida tilneyi sp. nov. and Candida powellii sp. nov. were recovered from bees and from nitidulid beetles in flowers of two species of morning glory (Ipomoea) in north-western Costa Rica. C. tilneyi sp. nov. is most closely related to Candida geochares, but differs in the D1D2 sequence by 4.7% base substitutions. C. powellii sp. nov. is a relative of Candida batistae and Candida floricola, showing sequence differences of 5.9 and 6.9%, respectively. In all cases, the new species are phenotypically similar to their nearest relatives, but are sufficiently different to allow conventional identification. The type strains are C. cleridarum strain UWO(PS) 99-101.1T ( = CBS 8793T), C. tilneyi strain UWO(PS) 99-325.1T ( = CBS 8794T) and C. powellii strain UWO(PS) 99-325.3T ( = CBS 8795T).
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Candida/clasificación , Insectos/microbiología , Filogenia , Animales , Asteraceae/parasitología , Candida/genética , Candida/aislamiento & purificación , Escarabajos/microbiología , Costa Rica , ADN Ribosómico/genética , Ecosistema , Fermentación , Frutas/microbiología , Datos de Secuencia Molecular , Tallos de la Planta/parasitologíaRESUMEN
Two new haplontic heterothallic species of Metschnikowia were isolated from floricolous insects and flowers. Metschnikowia lochheadii was recovered from insects found in various flowers on the Hawaiian Islands of Kauai and Maui, and from Conotelus sp. (Coleoptera: Nitidulidae) in northwestern Guanacaste Province, Costa Rica. The morphology, physiology, and sexual cycle are typical of the large-spored Metschnikowia species, and the partial ribosomal DNA large subunit (D1D2) sequences suggest that the new species is most closely related to Candida ipomoeae. Metschnikowia lochheadii is nearly indistinguishable from its ascogenous relatives and conjugates freely with Metschnikowia continentalis, forming sterile asci. It also exhibits asymmetric mating with Metschnikowia hawaiiensis. Metschnikowia drosophilae was found in morning glory (Ipomoea sp.) flowers and associated Drosophila bromeliae on Grand Cayman Island. Its nutritional profile is atypical of the genus, being the only species that does not utilize sucrose or maltose as carbon sources, and one of the few that does not utilize melezitose. D1D2 sequences show that Metschnikowia drosophilae is a sister species to Candida torresii, to which it bears considerable similarity in nutritional profile. The type cultures are: Metschnikowia lochheadii, strains UWO(PS)00-133.2 = CBS 8807 (h+, holotype) UWO(PS)99-661.1 = CBS 8808 (h-, isotype); and Metschnikowia drosophilae, strains UWO(PS)83-1135.3 = CBS 8809 (h+, holotype) and UWO(PS)83-1143.1 = CBS 8810 (h-, isotype).
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Insectos/microbiología , Plantas/microbiología , Levaduras/clasificación , Animales , Costa Rica , Genoma Fúngico , Hawaii , Datos de Secuencia Molecular , Filogenia , Levaduras/genéticaRESUMEN
Sensory nerve potential area measurements may reflect the properties of underlying nerve fibres better than amplitude or conduction velocity measures. The terminal segment of the sensory curve may contain activity of regenerating nerve fibres. The reliability of area measurements of sensory potentials obtained with surface recording techniques is unknown. We scanned sural nerve sensory potential curves and measured the areas under different parts of the curve in 52 reference and 73 diabetic polyneuropathy (DPN) patients. The variability of repeat testing in reference subjects for total area was 12% and for the terminal segmental area (TSA) was 19%. In DPN patients, the total area variability was 17% and TSA variability was 24%. This compares to amplitude variability of 8% in reference subjects and 10% in patients with DPN. These results demonstrate that sensory potential area measurements are feasible, but highly variable. We conclude that current clinical trials do not include sufficient numbers of patients to show change in area measurements, particularly the area under the terminal segment of the curve.