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2.
Int J Biometeorol ; 61(9): 1667-1673, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28382376

RESUMEN

Although the responses of living organisms to climate change are being widely investigated, little attention has been given to such effects late in the growing season. We studied the late-season flight times of 20 species of butterflies in a geographically limited region, the state of Massachusetts in the USA, by examining change in dates of flight over a 22-year period and in response to average monthly temperature and precipitation. By analyzing the last 10% of each year's observations reported by observers of the Massachusetts Butterfly Club, we found that seven species remain in flight significantly later into the fall than they did two decades earlier, while two species show reduced late-season flight. Life history characteristics of the species, particularly voltinism and average fall flight dates, influenced whether warmer fall months led to increases or decreases in fall flight. Warmer Novembers often led to later fall flight, and wetter Augusts usually extended fall flight. These results document the effects of climate on late-season flight times of butterflies, add to an understanding of how warmer autumn conditions alter the phenology of different butterfly species, and show the usefulness of citizen science data.


Asunto(s)
Mariposas Diurnas/fisiología , Cambio Climático , Vuelo Animal , Estaciones del Año , Animales , Massachusetts , Tiempo (Meteorología)
3.
AJNR Am J Neuroradiol ; 33(2): 203-10, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21527571

RESUMEN

High-resolution MRN is becoming increasingly available due to recent technical advancements, including higher magnetic field strengths (eg, 3T), 3D image acquisition, evolution of novel fat-suppression methods, and improved coil design. This review describes the MRN techniques for obtaining high-quality images of the peripheral nerves and their small branches and imaging findings in normal as well as injured nerves with relevant intraoperative correlations. Various microsurgical techniques in peripheral nerves, such as neurolysis, nerve repairs by using nerve grafts, and conduits are discussed, and MRN findings of surgically treated nerves are demonstrated.


Asunto(s)
Nervios Periféricos/diagnóstico por imagen , Nervios Periféricos/cirugía , Humanos , Imagen por Resonancia Magnética , Neurorradiografía/métodos , Procedimientos Neuroquirúrgicos/métodos
4.
AJNR Am J Neuroradiol ; 31(8): 1363-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20133388

RESUMEN

MR imaging of peripheral nerves has been described in relation to abnormalities such as nerve injury, entrapment, and neoplasm. Neuroma formation is a known response to peripheral nerve injury, and here we correlate the MRN appearance of postinjury neuroma formation with intraoperative findings. We also present the MR imaging features of surgical treatment with a synthetic nerve tube and nerve wrap on postoperative follow-up imaging.


Asunto(s)
Imagen por Resonancia Magnética , Neuroma/patología , Neuroma/cirugía , Neoplasias del Sistema Nervioso Periférico/patología , Neoplasias del Sistema Nervioso Periférico/cirugía , Humanos , Síndromes de Compresión Nerviosa/patología , Síndromes de Compresión Nerviosa/cirugía , Traumatismos de los Nervios Periféricos , Nervios Periféricos/patología , Nervios Periféricos/cirugía
6.
J Comb Chem ; 2(2): 151-71, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10757095

RESUMEN

A new tool for analyzing compound libraries by NMR has been developed. Aliquots of solution-state samples (between 120 and 350 microL) are directly injected, using a standard liquids handler, into an NMR (LC-NMR) flow probe. Automated NMR software tracks--and suppresses--intense signals arising from the nondeuterated solvents used (if any) and acquires high-sensitivity one-dimensional 1H NMR spectra. An 88-member combinatorial library, dissolved in DMSO and stored in a 96-well microtiter plate, has been analyzed a number of ways using this technique. This nondestructive technique, which we call direct-injection NMR (DI-NMR) and which is embodied in our versatile automated sample changer (VAST) hardware, has proven to be both routine and robust. Our success in automatically acquiring the NMR data for entire plates of library compounds (within 4-8 h) has caused us to develop new ways to display and analyze the resulting NMR data, as will be shown here.


Asunto(s)
Química Orgánica/métodos , Espectroscopía de Resonancia Magnética/métodos , Cromatografía Liquida , Cromatografía en Capa Delgada , Recolección de Datos , Bases de Datos Factuales , Dimetilsulfóxido/química , Espectroscopía de Resonancia Magnética/instrumentación , Espectrometría de Masas , Programas Informáticos , Solventes
7.
Genetics ; 154(3): 999-1012, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10757749

RESUMEN

Translation of mitochondrially coded mRNAs in Saccharomyces cerevisiae depends on membrane-bound mRNA-specific activator proteins, whose targets lie in the mRNA 5'-untranslated leaders (5'-UTLs). In at least some cases, the activators function to localize translation of hydrophobic proteins on the inner membrane and are rate limiting for gene expression. We searched unsuccessfully in divergent budding yeasts for orthologs of the COX2- and COX3-specific translational activator genes, PET111, PET54, PET122, and PET494, by direct complementation. However, by screening for complementation of mutations in genes adjacent to the PET genes in S. cerevisiae, we obtained chromosomal segments containing highly diverged homologs of PET111 and PET122 from Saccharomyces kluyveri and of PET111 from Kluyveromyces lactis. All three of these genes failed to function in S. cerevisiae. We also found that the 5'-UTLs of the COX2 and COX3 mRNAs of S. kluyveri and K. lactis have little similarity to each other or to those of S. cerevisiae. To determine whether the PET111 and PET122 homologs carry out orthologous functions, we deleted them from the S. kluyveri genome and deleted PET111 from the K. lactis genome. The pet111 mutations in both species prevented COX2 translation, and the S. kluyveri pet122 mutation prevented COX3 translation. Thus, while the sequences of these translational activator proteins and their 5'-UTL targets are highly diverged, their mRNA-specific functions are orthologous.


Asunto(s)
Regiones no Traducidas 5' , Complejo IV de Transporte de Electrones/genética , Proteínas Fúngicas/genética , Isoenzimas/genética , Proteínas de la Membrana/genética , Proteínas Nucleares/fisiología , Prostaglandina-Endoperóxido Sintasas/genética , Biosíntesis de Proteínas , ARN de Hongos , ARN , Proteínas de Saccharomyces cerevisiae , Secuencia de Aminoácidos , Animales , Ciclooxigenasa 2 , Genes Fúngicos , Prueba de Complementación Genética , Kluyveromyces/clasificación , Kluyveromyces/genética , Proteínas Mitocondriales , Datos de Secuencia Molecular , Mutagénesis , Proteínas Nucleares/genética , Factores de Iniciación de Péptidos , Fenotipo , ARN Mitocondrial , Saccharomyces/clasificación , Saccharomyces/genética , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/genética , Homología de Secuencia de Ácido Nucleico
8.
J Parasitol ; 85(6): 1036-40, Dec. 1999.
Artículo en Inglés | MedCarib | ID: med-758

RESUMEN

Nerocila benrosei n. sp. is described from the hogfish, Lachnolaimus maximus (Walbaum), the Spanish hogfish, Bodianus rufus (Linnaeus), (Perciformes: Labridae) from the Northern Bahamas. Nerocila benrosei differs from all species of Nerocila by having the body of females 1.4 to 1.9 times as wide, as long, instead of 2.0 - 3.0 times) and pleopods 1 and 2 lacking accessory lamellae. It differs from the only species of Nerocila with which it overlaps geographically, N. lanceolata (Say, 1818), by having the lateral margins of pleonites 1-5 strongly produced ventrally, coxae 5-7 manifestly shorter than the posterolateral projection of the respective pereonite, and a vaulted dorsal surface. The species of Nerocila in the northwestern Atlantic have almost mutually exclusive geographic ranges: New England to Panama, including Bermuda and the northern coast of Cuba (Nerocila lanceolata); Brazil to Trinidad and Tobago (Nerocila fluviatilis Schiodte and Meinert, 1881); and the northern Bahamas and Bermuda (Nerocila benrosei). No species of Nerocila have been reported from the insular Caribbean. Nerocila benrosei appears to be highly host and site specific. (AU)


Asunto(s)
21003 , Femenino , Masculino , Crustáceos , Enfermedades de los Peces/parasitología , Perciformes/parasitología , Infestaciones Ectoparasitarias/veterinaria , Bahamas , Crustáceos/anatomía & histología , Crustáceos/clasificación , Infestaciones Ectoparasitarias/parasitología
9.
Proc Natl Acad Sci U S A ; 96(7): 4198-203, 1999 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-10097187

RESUMEN

Vitamin C (L-ascorbic acid; AsA) acts as a potent antioxidant and cellular reductant in plants and animals. AsA has long been known to have many critical physiological roles in plants, yet its biosynthesis is only currently being defined. A pathway for AsA biosynthesis that features GDP-mannose and L-galactose has recently been proposed for plants. We have isolated a collection of AsA-deficient mutants of Arabidopsis thaliana that are valuable tools for testing of an AsA biosynthetic pathway. The best-characterized of these mutants (vtc1) contains approximately 25% of wild-type AsA and is defective in AsA biosynthesis. By using a combination of biochemical, molecular, and genetic techniques, we have demonstrated that the VTC1 locus encodes a GDP-mannose pyrophosphorylase (mannose-1-P guanyltransferase). This enzyme provides GDP-mannose, which is used for cell wall carbohydrate biosynthesis and protein glycosylation as well as for AsA biosynthesis. In addition to genetically defining the first locus involved in AsA biosynthesis, this work highlights the power of using traditional mutagenesis techniques coupled with the Arabidopsis Genome Initiative to rapidly clone physiologically important genes.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Ácido Ascórbico/biosíntesis , Guanosina Difosfato Manosa/metabolismo , Manosa/metabolismo , Nucleotidiltransferasas/genética , Secuencia de Aminoácidos , Arabidopsis/efectos de los fármacos , Secuencia de Bases , Radioisótopos de Carbono , ADN Complementario , Prueba de Complementación Genética , Metilnitronitrosoguanidina/farmacología , Datos de Secuencia Molecular , Mutagénesis , Mutágenos/farmacología , Nucleotidiltransferasas/química , Nucleotidiltransferasas/metabolismo , Plantas Modificadas Genéticamente , Técnica de Dilución de Radioisótopos , Alineación de Secuencia , Homología de Secuencia de Aminoácido
10.
Vet Parasitol ; 81(1): 69-71, 1999 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9950330

RESUMEN

Endangered West Indian manatees (Trichechus manatus) are known to be parasitized by a number of helminths and ectoparasites. Records of parasitic associations exist for Florida, Mexico, Guyana, Brazil, Cuba and recently for Puerto Rico. Parasites of manatees in other Caribbean areas have not been documented, particularly from Hispaniola. We report on the occurrence of a species of nematode and of two trematodes from a 238-cm male manatee from Portillo (19 degrees 20' N, 69 degrees 35' W), Las Terrenas, in the Dominican Republic. Three species of helminths were collected, including the opisthotrematid Cochleotrema cochleotrema, the ascarid Heterocheilus tunicatus, and the paramphistomid trematode Chiorchis fabaceus. The documentation of these helminths constitutes the first record of these parasites and host relationships for Hispaniola and the second for the northeastern Caribbean.


Asunto(s)
Helmintiasis Animal/parasitología , Nematodos/aislamiento & purificación , Trematodos/aislamiento & purificación , Trichechus manatus/parasitología , Animales , República Dominicana , Masculino
11.
J Parasitol ; 85(6): 1036-40, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10647034

RESUMEN

Nerocila benrosei n. sp. is described from the hogfish, Lachnolaimus maximus (Walbaum), and the Spanish hogfish, Bodianus rufus (Linnaeus), (Perciformes: Labridae) from the northern Bahamas. Nerocila benrosei differs from all species of Nerocila by having the body of females 1.4-1.9 times as wide as long, instead of 2.0-3.0 times, and pleopods 1 and 2 lacking accessory lamellae. It differs from the only species of Nerocila with which it overlaps geographically, N. lanceolata (Say, 1818), by having the lateral margins of pleonites 1-5 strongly produced ventrally, coxae 5-7 manifestly shorter than the posterolateral projection of the respective pereonite, and a vaulted dorsal surface. The species of Nerocila in the northwestern Atlantic have almost mutually exclusive geographic ranges: New England to Panama, including Bermuda and the northern coast of Cuba (Nerocila lanceolata); Brazil to Trinidad and Tobago (Nerocila fluviatilis Schiödte and Meinert, 1881); and the northern Bahamas and Bermuda (Nerocila benrosei). No species of Nerocila have been reported from the insular Caribbean. Nerocila benrosei appears to be highly host and site specific.


Asunto(s)
Crustáceos , Infestaciones Ectoparasitarias/veterinaria , Enfermedades de los Peces/parasitología , Perciformes/parasitología , Animales , Bahamas , Crustáceos/anatomía & histología , Crustáceos/clasificación , Infestaciones Ectoparasitarias/parasitología , Femenino , Masculino
12.
J Hand Surg Am ; 23(5): 805-10, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9763253

RESUMEN

The volar plate (VP) is critical to the stability of the proximal interphalangeal joint. This study clarifies the macro- and micro-architectural structure of the VP and correlates these findings with its functional properties. Microscopic evaluation of cadaver specimens revealed a trilaminar structure of the VP with differential orientation and organization of collagen fibers in the volar, central core, and dorsal check rein sections of the plate. This description differs from the existing literature and adds to the understanding of the functional properties of the VP. The most important finding is a dense "basket weave" of collagen fibers oriented in 2 perpendicular planes within the central core of the VP. This orientation may contribute primarily to the resistance of the VP to both longitudinal and torsional stress. This study adds to the understanding of the histologic basis for the function of the VP and the mechanisms involved in its injury.


Asunto(s)
Cartílago Articular/anatomía & histología , Cartílago Articular/patología , Articulaciones de los Dedos/anatomía & histología , Articulaciones de los Dedos/patología , Cadáver , Técnicas de Cultivo , Humanos , Ligamentos Articulares/anatomía & histología , Fotomicrografía , Propiedades de Superficie
14.
J Parasitol ; 84(5): 939-46, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9794635

RESUMEN

The parasite fauna in cetaceans from Puerto Rico, the Virgin Islands, and the larger Caribbean region is poorly known. We provide the first records for parasite biodiversity among a diverse assemblage of cetaceans from the Caribbean Sea. Internal and external parasites and commensals were collected from stranded whales and dolphins salvaged in Puerto Rico, the United States and British Virgin Islands, Jamaica, and Venezuela between 1989 and 1997. A total of 47 individuals of 16 species of whales and dolphins (15 odontocetes and 1 mysticete) was examined. Overall, parasites and commensals were found in 34 (72.3%) animals, representing 13 species of odontocetes and 1 mysticete. Eighteen species of endoparasitic helminths were found, including 8 species of nematodes, 2 digeneans, 6 cestodes, and 2 acanthocephalans. Three species of whale-lice and 2 species of barnacles were also collected.


Asunto(s)
Crustáceos/clasificación , Delfines/parasitología , Infestaciones Ectoparasitarias/veterinaria , Helmintiasis Animal/parasitología , Helmintos/clasificación , Ballenas/parasitología , Animales , Región del Caribe , Delfines/clasificación , Infestaciones Ectoparasitarias/parasitología , Femenino , Masculino , Simbiosis , Ballenas/clasificación
15.
Proc Natl Acad Sci U S A ; 93(18): 9970-4, 1996 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-8790441

RESUMEN

L-ascorbic acid (vitamin C) is a powerful reducing agent found in millimolar concentrations in plants, and is proposed to play an important role in scavenging free radicals in plants and animals. However, surprisingly little is known about the role of this antioxidant in plant environmental stress adaptation or ascorbate biosynthesis. We report the isolation of soz1, a semi-dominant ozone-sensitive mutant that accumulates only 30% of the normal ascorbate concentration. The results of genetic approaches and feeding studies show that the ascorbate concentration affects foliar resistance to the oxidizing gas ozone. Consistent with the proposed role for ascorbate in reactive oxygen species detoxification, lipid peroxides are elevated in soz1, but not in wild type following ozone fumigation. We show that the soz1 mutant is hypersensitive to both sulfur dioxide and ultraviolet B irradiation, thus implicating ascorbate in defense against varied environmental stresses. In addition to defining the first ascorbate deficient mutant in plants, these results indicate that screening for ozone-sensitive mutants is a powerful method for identifying physiologically important antioxidant mechanisms and signal transduction pathways. Analysis of soz1 should lead to more information about the physiological roles and metabolism of ascorbate.


Asunto(s)
Arabidopsis/genética , Ácido Ascórbico/metabolismo , Arabidopsis/metabolismo , Mutación , Ozono/farmacología
16.
J Chem Ecol ; 22(12): 2341-57, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24227308

RESUMEN

Ovipositing black swallowtail butterflies,Papilio polyxenes, make their final host-selection decisions on the basis of compounds present on the leaf surface. Little information is available, however, on the chemistry of leaf surfaces. The purpose of this study was to develop a technique to extract and quantify the concentrations of compounds from the leaf surfaces ofDaucus carota, one of the main host species forP. polyxenes, with particular reference to compounds already identified as contact oviposition stimulants, namelytrans-chlorogenic acid (CA) and luteolin-7-O-(6″-O-malonyl)-ß-D-glucopyranoside (L7MG), as well as its degradation product luteolin-7-glucoside (L7G). Plant surfaces were extracted by dipping leaves sequentially in pairs of solvents: (1) CHCl3-MeOH, (2) near-boiling H2O, (3) CHCl3-near-boiling H2O, and (4) CH2Cl2-CH2Cl2. The resulting extracts were fractionated and analyzed using high-performance liquid chromatography. The leaf-surface concentrations of each compound were calculated using regressions relating leaf surface area to leaf weight that were obtained from measurements of field-collected carrot plants. All four methods removed the three compounds from carrot leaf surfaces, but the solvent systems differed in effectiveness. The chloroform-near-boiling water solvent system performed better than the other solvent combinations, but not significantly so. This system also extracted the highest number of polar, UV-absorbing compounds. Methylene chloride was significantly less efficient than the other methods. An additional test confirmed that the chloroform-near-boiling water method removed compounds from the surface alone and probably not from the apoplast or symplast. Surface concentrations of CA (up to 600 ng/cm(2) leaf surface) were substantially greater than those of the two flavonoid compounds. No clear seasonal trend in concentrations was evident from the limited number of sampling dates.

19.
J Invertebr Pathol ; 61(2): 206-10, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8463711

RESUMEN

The stock of Nasonia vitripennis marked by the nuclear eye color mutation "tinged" (ti) shows nonreciprocal cytoplasmic incompatibility with wild-type (+) strains. Homogenates prepared from ti female pupae and injected into + female pupae caused 39% of the recipients to acquire the incompatibility characteristics of the ti donors. When eggs obtained from ti females were fragmented and injected into + female pupae, or when the ti egg cytoplasm was injected into chick eggs and yolk sac homogenates were subsequently injected into + female pupae, 28% of the recipients acquired ti-type incompatibility characteristics. Results from passage of the egg cytoplasm through 0.23-microns millipore filters showed successful transfer of the incompatibility and suggest that the incompatibility system in N. vitripennis has two components: a bacterium and a smaller agent.


Asunto(s)
Herencia Extracromosómica , Avispas/genética , Avispas/microbiología , Animales , Femenino
20.
J Parasitol ; 78(3): 399-401, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1597779

RESUMEN

Neobenedenia pargueraensis n. sp. from Epinephelus guttatus of Puerto Rico differs from all known species in possessing scoop-shaped accessory sclerites with pointed tips. It is most similar to Neobenedenia melleni and Neobenedenia longiprostata but differs from the former in having a fenestrate ovary and from the latter in that the ducts of the accessory glands are short, terminating just anterior to the vitelline reservoir rather than reaching the caudal end of the body. It differs from both species in having smooth rather than lobate testes. Neobenedenia melleni occurs throughout the tropical and subtropical western North Atlantic including Bermuda. It kills aquarium and aquaculture fishes with massive infestations and is a severe restraint on the culture of tilapia in sea water in the Caribbean.


Asunto(s)
Lubina/parasitología , Enfermedades de los Peces/parasitología , Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Animales , Branquias/parasitología , Trematodos/anatomía & histología , Infecciones por Trematodos/parasitología
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