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1.
Ultrasound Obstet Gynecol ; 62(1): 75-87, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37099500

RESUMEN

OBJECTIVE: Fetuses with congenital heart disease (CHD) are at increased risk of pregnancy loss compared with the general population. We aimed to assess the incidence, timing and risk factors of pregnancy loss in cases with major fetal CHD, overall and according to cardiac diagnosis. METHODS: This was a retrospective, population-level cohort study of fetuses and infants diagnosed with major CHD between 1997 and 2018 identified by the Utah Birth Defect Network (UBDN), excluding cases with termination of pregnancy and minor cardiovascular diagnoses (e.g. isolated aortic/pulmonary pathology and isolated septal defects). The incidence and timing of pregnancy loss were recorded, overall and according to CHD diagnosis, with further stratification based on presence of isolated CHD vs additional fetal diagnosis (genetic diagnosis and/or extracardiac malformation). Adjusted risk of pregnancy loss was calculated and risk factors were assessed using multivariable models for the overall cohort and prenatal diagnosis subgroup. RESULTS: Of 9351 UBDN cases with a cardiovascular code, 3251 cases with major CHD were identified, resulting in a study cohort of 3120 following exclusion of cases with pregnancy termination (n = 131). There were 2956 (94.7%) live births and 164 (5.3%) cases of pregnancy loss, which occurred at a median gestational age of 27.3 weeks. Of study cases, 1848 (59.2%) had isolated CHD and 1272 (40.8%) had an additional fetal diagnosis, including 736 (57.9%) with a genetic diagnosis and 536 (42.1%) with an extracardiac malformation. The observed incidence of pregnancy loss was highest in the presence of mitral stenosis (< 13.5%), hypoplastic left heart syndrome (HLHS) (10.7%), double-outlet right ventricle with normally related great vessels or not otherwise specified (10.5%) and Ebstein's anomaly (9.9%). The adjusted risk of pregnancy loss was 5.3% (95% CI, 3.7-7.6%) in the overall CHD population and 1.4% (95% CI, 0.9-2.3%) in cases with isolated CHD (adjusted risk ratio, 9.0 (95% CI, 6.0-13.0) and 2.0 (95% CI, 1.0-6.0), respectively, based on the general population risk of 0.6%). On multivariable analysis, variables associated with pregnancy loss in the overall CHD population included female fetal sex (adjusted odds ratio (aOR), 1.6 (95% CI, 1.1-2.3)), Hispanic ethnicity (aOR, 1.6 (95% CI, 1.0-2.5)), hydrops (aOR, 6.7 (95% CI, 4.3-10.5)) and additional fetal diagnosis (aOR, 6.3 (95% CI, 4.1-10)). On multivariable analysis of the prenatal diagnosis subgroup, years of maternal education (aOR, 1.2 (95% CI, 1.0-1.4)), presence of an additional fetal diagnosis (aOR, 2.7 (95% CI, 1.4-5.6)), atrioventricular valve regurgitation ≥ moderate (aOR, 3.6 (95% CI, 1.3-8.8)) and ventricular dysfunction (aOR, 3.8 (95% CI, 1.2-11.1)) were associated with pregnancy loss. Diagnostic groups associated with pregnancy loss were HLHS and variants (aOR, 3.0 (95% CI, 1.7-5.3)), other single ventricles (aOR, 2.4 (95% CI, 1.1-4.9)) and other (aOR, 0.1 (95% CI, 0-0.97)). Time-to-pregnancy-loss analysis demonstrated a steeper survival curve for cases with an additional fetal diagnosis, indicating a higher rate of pregnancy loss compared to cases with isolated CHD (P < 0.0001). CONCLUSIONS: The risk of pregnancy loss is higher in cases with major fetal CHD compared with the general population and varies according to CHD type and presence of additional fetal diagnoses. Improved understanding of the incidence, risk factors and timing of pregnancy loss in CHD cases should inform patient counseling, antenatal surveillance and delivery planning. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Aborto Inducido , Aborto Espontáneo , Corazón Fetal , Cardiopatías Congénitas , Femenino , Humanos , Lactante , Embarazo , Aborto Espontáneo/epidemiología , Estudios de Cohortes , Enfermedades Fetales , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Incidencia , Estudios Retrospectivos , Factores de Riesgo , Ultrasonografía Prenatal
2.
Can Prosthet Orthot J ; 4(2): 35958, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-37614996

RESUMEN

The goal of health economics and outcomes research is to improve healthcare decision making. In the absence of high-value clinical data, the availability and quality of administrative healthcare data could be vital in the generation of evidence for orthotics and prosthetics services. The purpose of this article is to provide a stronger understanding of administrative healthcare data analysis, an area that has been scarcely examined within prosthetics and orthotics despite the wealth of information available within such data. Examples of common datasets in this arena currently available are provided, as well as an overview of the limitations and advantages of studies utilizing such datasets.

3.
Can Prosthet Orthot J ; 4(2): 35959, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-37615002

RESUMEN

The demand has increased for evidence regarding the effectiveness and value of prosthetic and orthotic rehabilitation interventions. Clinicians and managers are under pressure to provide treatment recommendations and demonstrate effectiveness through outcomes. It is often assumed that rehabilitation interventions, including the provision of custom-made and custom-fit orthotic and prosthetic devices, are beneficial to patients. Assessing the value of orthotic and prosthetic services has become more critical to continue to ensure equitable access to needed services. Health economics and outcomes research methods serve as tools to gauge the value of prosthetic and orthotic rehabilitation interventions. The purpose of this article is to provide an overview of the current need of health economics and outcomes research in orthotics and prosthetics, to introduce common economic methods that assist to generate real-world evidence, and to discusses the potential value of economic methods for clinicians and clinical practice.

4.
Phys Chem Chem Phys ; 21(24): 13374, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31169272

RESUMEN

Correction for 'Sub-Doppler infrared spectroscopy of resonance-stabilized hydrocarbon intermediates: ν3/ν4 CH stretch modes and CH2 internal rotor dynamics of benzyl radical' by A. Kortyna et al., Phys. Chem. Chem. Phys., 2017, 19, 29812-29821.

5.
Phys Chem Chem Phys ; 19(44): 29812-29821, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29099133

RESUMEN

Highly reactive benzyl radicals are generated by electron dissociative attachment to benzyl chloride doped into a neon-hydrogen-helium discharge and immediately cooled to Trot = 15 K in a high density, supersonic slit expansion environment. The sub-Doppler spectra are fit to an asymmetric-top rotational Hamiltonian, thereby yielding spectroscopic constants for the ground (v = 0) and first excited (v = 1, ν3, ν4) vibrational levels of the ground electronic state. The rotational constants obtained for the ground state are in good agreement with previous laser induced fluorescence measurements (LIF), with vibrational band origins (ν3 = 3073.2350 ± 0.0006 cm-1, ν4 = 3067.0576 ± 0.0006 cm-1) in agreement with anharmonically corrected density functional theory calculations. To assist in detection of benzyl radical in the interstellar medium, we have also significantly improved the precision of the ground state rotational constants through combined analysis of the ground state IR and LIF combination differences. Of dynamical interest, there is no evidence in the sub-Doppler spectra for tunneling splittings due to internal rotation of the CH2 methylene subunit, which implies a significant rotational barrier consistent with partial double bond character in the CC bond. This is further confirmed with high level ab initio calculations at the CCSD(T)-f12b/ccpVdZ-f12 level, which predict a zero-point energy corrected barrier to internal rotation of ΔEtun ≈ 11.45 kcal mol-1 or 4005 cm-1. In summary, the high-resolution infrared spectra are in excellent agreement with simple physical organic chemistry pictures of a strongly resonance-stabilized benzyl radical with a nearly rigid planar structure due to electron delocalization around the aromatic ring.

6.
Phys Rev Lett ; 115(26): 264801, 2015 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-26764995

RESUMEN

Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. To date, the implemented compensation scheme approximately doubled the peak and average luminosities.

7.
Struct Dyn ; 1(3): 034301, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-26798776

RESUMEN

We report measurements of the transient structural response of weakly photo-excited thin films of BiFeO3, Pb(Zr,Ti)O3, and Bi and time-scales for interfacial thermal transport. Utilizing picosecond x-ray diffraction at a 1.28 MHz repetition rate with time resolution extending down to 15 ps, transient changes in the diffraction angle are recorded. These changes are associated with photo-induced lattice strains within nanolayer thin films, resolved at the part-per-million level, corresponding to a shift in the scattering angle three orders of magnitude smaller than the rocking curve width and changes in the interlayer lattice spacing of fractions of a femtometer. The combination of high brightness, repetition rate, and stability of the synchrotron, in conjunction with high time resolution, represents a novel means to probe atomic-scale, near-equilibrium dynamics.

8.
Nat Commun ; 4: 1369, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23340409

RESUMEN

Superionic materials are multi-component solids with simultaneous characteristics of both a solid and a liquid. Above a critical temperature associated with a structural phase transition, they exhibit liquid-like ionic conductivities and dynamic disorder within a rigid crystalline structure. Broad applications as electrochemical storage materials and resistive switching devices follow from this abrupt change in ionic mobility, but the microscopic pathways and speed limits associated with this switching process are largely unknown. Here we use ultrafast X-ray spectroscopy and scattering techniques to obtain an atomic-level, real-time view of the transition state in copper sulphide nanocrystals. We observe the transformation to occur on a twenty picosecond timescale and show that this is determined by the ionic hopping time.

9.
Can J Neurol Sci ; 39(5): 577-83, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22931697

RESUMEN

Piriformis Syndrome (PS) is an uncommon, controversial neuromuscular disorder that is presumed to be a compression neuropathy of the sciatic nerve at the level of the piriformis muscle (PM). The diagnosis is hampered by a lack of agreed upon clinical criteria and a lack of definitive investigations such as imaging or electrodiagnostic testing. Treatment has focused on stretching, physical therapies, local injections, including botulinum toxin, and surgical management. This article explores the various sources of controversy surrounding piriformis syndrome including diagnosis, investigation and management. We conclude with a proposal for diagnostic criteria which include signs and symptoms, imaging, and response to therapeutic injections.


Asunto(s)
Síndrome del Músculo Piriforme/diagnóstico , Síndrome del Músculo Piriforme/terapia , Diagnóstico por Imagen , Electrodiagnóstico , Humanos
10.
Am J Rhinol Allergy ; 25(5): 369, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29021069

RESUMEN

INTRODUCTION: To establish the efficacy of bepotastine besilate ophthalmic solution (bepotastine) 1.5%, a dual acting histamine H1 receptor antagonist approved for treatment of ocular itching associated with allergic conjunctivitis, compared to placebo in relieving ocular itching and redness for subjects with active allergic rhinoconjunctivitis. METHODS: A randomized, double-masked, placebo-controlled, confirmatory natural exposure study of bepotastine 1.5% and placebo was conducted during allergy season at 12 clinical sites throughout the U.S. Following a 7-day screening period, eligible subjects ≥12 years old were assigned in a 1:1 ratio to dosing OU b.i.d. either bepotastine 1.5% (n = 123) or placebo (n = 122). Subjects recorded instantaneous grades for their ocular symptoms prior to their next dose for 14 consecutive days. Clinically significant reduction in ocular sign or symptom grades between treatment groups required p ≤ 0.05 as determined by ANCOVA analysis. RESULTS: Significant clinical effectiveness with bepotastine 1.5% was demonstrated over the 2-week treatment period in comparison to placebo in the intent-to-treat population for reducing mean instantaneous grades for both ocular itching (p = 0.007) and redness (p = 0.001). Investigator rating of efficacy over the 2-week treatment period across response categories was also superior for bepotastine 1.5% compared to placebo (p = 0.024). Only one subject discontinued participation in the study due to an adverse event. CONCLUSIONS: These data support bepotastine 1.5% as an effective treatment for allergen-induced signs and symptoms in a clinical study designed to closely resemble the conditions under which patients with allergic rhinoconjunctivitis would require treatment.

11.
Exp Brain Res ; 204(1): 139-44, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20490783

RESUMEN

During prolonged contractions, few studies have reported rotation among low threshold motoneurons. The question arises whether a motoneuron stops firing due to an increase in firing threshold or whether it is due to regional switching of activity among muscle fascicles. We postulated that if the rest period resulted from an increase in firing threshold, a progressive recovery in the excitability of the motoneuron would be observed during the rest period. The excitability of soleus or tibialis anterior motoneurons was tested during the rest periods. The results showed that a previously tonic motoneuron that had dropped off during rotation, rarely responded to Ia or TMS inputs in the initial parts of the rest period; however, its response probability increased significantly in the second half. Based on these data, we suggest that the observed rotation is due to changes in firing thresholds of motoneurons during prolonged firing.


Asunto(s)
Potenciales de Acción/fisiología , Neuronas Motoras/fisiología , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiología , Adulto , Anciano , Electromiografía , Femenino , Humanos , Pierna/fisiología , Masculino , Persona de Mediana Edad , Modelos Biológicos , Probabilidad , Descanso , Rotación , Factores de Tiempo , Adulto Joven
12.
Insect Mol Biol ; 19(2): 177-84, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20017756

RESUMEN

A transgenic line of the pink bollworm, Pectinophora gossypiella, a key lepidopteran cotton pest, was generated previously using the piggyBac transposon IFP2 from Trichoplusia ni. Here we identified an endogenous piggyBac-like element (PLE), designated as PgPLE1, in the pink bollworm. A putatively intact copy of PgPLE1 (PgPLE1.1) presents the canonical features of PLE: inverted terminal repeats with three C/G residues at the extreme ends, inverted subterminal repeats, TTAA target site and an open reading frame encoding transposase with 68% similarity to IFP2. Vectorette PCR revealed large variation in the insertion sites of PgPLE1 amongst worldwide populations, indicating the potential mobility of PgPLE1. The PgPLE1 was undetectable in the genome of Pectinophora endema, implying the recent invasion of PgPLE1 after the divergence of these two closely related species.


Asunto(s)
Elementos Transponibles de ADN/genética , Lepidópteros/genética , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Cartilla de ADN/genética , Genes de Insecto , Proteínas de Insectos/genética , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Secuencias Repetidas Terminales , Transposasas/genética
13.
J Nanosci Nanotechnol ; 9(12): 6834-43, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19908687

RESUMEN

Superparamagnetic iron oxide nanoparticles are used in diverse applications, such as targeted drug delivery, magnetic resonance imaging and hyperthermic malignant cell therapy. In the current work, superparamagnetic iron oxide nanoparticles were produced by flame synthesis, which has improved nanoparticle property control and is capable of commercial production rates with minimal post-processing. The iron oxide nanoparticle material characteristics were analyzed by electron microscopy and Raman spectroscopy. Finally, flame synthesized iron oxide nanoparticle interaction with endothelial cells was compared to commercially available iron oxide nanoparticles. Flame synthesis produced a heterogeneous mixture of 6-12 nm diameter hematite and magnetite nanoparticles with superparamagnetic properties. Endothelial cell scanning electron microscopy, confirmed by energy dispersive spectroscopy, demonstrated that flame synthesized nanoparticles are ingested into cells in a similar manner to commercially available nanoparticles. The flame synthesized particles showed no statistically significant toxicity difference from commercially available nanoparticles, as measured by Live/Dead assay, Alamar blue, and lactase dehydrogenase release. Neither type of nanoparticle affected cell proliferation induced by fibroblast growth factor-2. These data suggest that combustion synthesized iron oxide nanoparticles are comparable to commercially available nanoparticles for biological applications, yet flame synthesis is a simpler process with higher purity products and lower manufacturing costs. Future work will include functionalizing nanoparticles for specific cell targeting and bioactive factor delivery.


Asunto(s)
Cristalización/métodos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Compuestos Férricos/farmacología , Compuestos Férricos/farmacocinética , Nanoestructuras/administración & dosificación , Nanoestructuras/química , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales/patología , Calor , Sustancias Macromoleculares/química , Magnetismo , Ensayo de Materiales , Conformación Molecular , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Tamaño de la Partícula , Propiedades de Superficie , Porcinos
14.
Insect Mol Biol ; 17(1): 9-18, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18237280

RESUMEN

Two piggyBac-like elements (PLEs) were identified in the cotton bollworm, Helicoverpa armigera, and were designated as HaPLE1 and HaPLE2. HaPLE1 is flanked by 16 bp inverted terminal repeats (ITRs) and the duplicated TTAA tetranucleotide, and contains an open reading frame (ORF) of 1794 bp with the presumed DDD domain, indicating that this element may be an active autonomously mobile element. HaPLE2 was found with the same ITRs, but lacks the majority of an ORF-encoding transposase. Thus, this element was thought to be a non-autonomous element. Transposable element displays and distribution of the two PLEs in individuals from three different H. armigera populations suggest that transmobilization of HaPLE2 by the transposase of HaPLE1 may be likely, and mobilization of HaPLE1 might occur not only within the same individual, but also among different individuals. In addition, horizontal transfer was probably involved in the evolution of PLEs between H. armigera and Trichoplusia ni.


Asunto(s)
Elementos Transponibles de ADN , Lepidópteros/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN/química , ADN/genética , Lepidópteros/enzimología , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Secuencias Repetidas Terminales , Transposasas/genética
15.
Insect Mol Biol ; 15(4): 435-43, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16907830

RESUMEN

We identified two different groups of piggyBac-like elements (PLE) in the tobacco budworm, Heliothis virescens, and named them HvPLE1 and HvPLE2. An intact copy of HvPLE1 revealed the characteristics of PLE: inverted terminal repeats, inverted subterminal repeats, and an open reading frame encoding transposase, whereas other HvPLE1 copies and all the HvPLE2 copies carried disruptive mutations in the region encoding transposase. We also identified none to two bands per genome hybridized to a probe of Trichoplusia ni piggyBac in genomic Southern blotting, which are different from HvPLE1 or HvPLE2. Analysis of the sequences of multiple copies of HvPLE1 and HvPLE2 suggests that the PLEs are closely related to the T. ni piggyBac, of relatively young age, and independently entered the H. virescens genome.


Asunto(s)
Elementos Transponibles de ADN/genética , Mariposas Nocturnas/enzimología , Filogenia , Transposasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Southern Blotting , Análisis por Conglomerados , Cartilla de ADN , Componentes del Gen , Datos de Secuencia Molecular , Mariposas Nocturnas/genética , Análisis de Secuencia de ADN
16.
Lett Appl Microbiol ; 42(5): 514-20, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16620212

RESUMEN

AIMS: The objective of this study was to evaluate the effectiveness of antibiotics and antimicrobial peptides against 10 strains of Xylella fastidiosa. METHODS AND RESULTS: The minimal inhibitory concentration (MIC) of 12 antibiotics and 18 antimicrobial peptides were determined by agar dilution tests and growth inhibition assays. Antibiotics with the lowest MIC for X. fastidiosa strains were gentamicin, tetracycline, ampicillin, kanamycin, and novobiocin, chloramphenicol, and rifampin. Plate growth inhibition assays showed that four of the antimicrobial peptides (Magainin 2, Indolicidin, PGQ, and Dermaseptin) were toxic to all X. fastidiosa strains. CONCLUSION: All X. fastidiosa strains were sensitive to several groups of antibiotics, and minor differences in sensitivity to several antimicrobial peptides were observed among strains. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that antibiotics and antimicrobial peptides have some activity against the pathogen, X. fastidiosa and may have application in protecting plants from developing Pierce's disease.


Asunto(s)
Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Xylella/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Xylella/crecimiento & desarrollo
17.
J Photochem Photobiol B ; 84(1): 64-9, 2006 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-16540336

RESUMEN

The polar methanolic fraction (PMF) of the Hypericum perforatum L. extract has recently been developed and tested as a novel, natural photosensitizer for use in the photodynamic therapy (PDT), and photodynamic diagnosis (PDD). PMF has been tested on HL-60 leukemic cells and cord blood hemopoietic progenitors. In the present study, the efficacy of PMF as a phototoxic agent against urinary bladder carcinoma has been studied using the T24 (high grade metastatic cancer), and RT4 (primary low grade papillary transitional cell carcinoma) human bladder cancer cells. Following cell culture incubation, PMF was excited using 630 nm laser light. The photosensitizer exhibited significant photocytotoxicity in both cell lines at a concentration of 60microg/ml, with 4-8 J/cm(2) light dose, resulting in cell destruction from 80% to 86%. At the concentration of 20microg/ml PMF was not active in either cell line. These results were compared with the results obtained in the same cell lines, under the same conditions with a clinically approved photosensitizer, Photofrin. Photofrin was used in the maximum clinically tolerable dose of 4microg/ml, and it was also excited with 630 nm laser light. In the T24 cell Photofrin exhibited slightly less photocytotocixity, compared with PMF, resulting in 77% cell death with 8J/cm(2) light dose. However, against the RT4 cells Photofrin resulted in minimal cell death (9%) with even 8J/cm(2) light dose. Finally, the type of cell death induced by PMF photoactivation was studied using flow cytometry and DNA laddering. Cell death by PMF photodynamic action in these two bladder cell lines is caused predominently by apoptosis. The reported significant photocytotoxicity, selective localization, natural abundance, easy, and inexpensive preparation, underscore that the PMF extract hold the promise of being a novel, effective PDT photosensitizer.


Asunto(s)
Apoptosis/efectos de los fármacos , Fragmentación del ADN , Hypericum/química , Metanol/química , Fármacos Fotosensibilizantes/farmacología , Fitoterapia , Extractos Vegetales/farmacología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Relación Dosis-Respuesta en la Radiación , Humanos , Rayos Láser , Luz , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Extractos Vegetales/química
18.
Insect Mol Biol ; 15(6): 743-8, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17201767

RESUMEN

An intact mariner-like element was isolated from the genome of tobacco budworm, Heliothis virescens. This is the first report of an intact mariner element after the initial identification of Mos1 from Drosophila mauritiana. The full-length Hvmar1 has 30 bp inverted terminal repeats and a complete 1065 bp open reading frame (ORF) encoding the transposase with a 'D,D(34)D' motif in the catalytic domain. Polymerase chain reaction results show that at least one insertion of the Hvmar1 element is conserved in this Heliothis strain. Phylogenetic analysis demonstrated that Hvmar1 belongs to the irritans subfamily.


Asunto(s)
Elementos Transponibles de ADN/genética , Lepidópteros/genética , Nicotiana/parasitología , Secuencias Repetidas Terminales/genética , Secuencia de Aminoácidos , Animales , Southern Blotting , Dosificación de Gen , Genoma de los Insectos/genética , Proteínas de Insectos/química , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Transposasas/química , Transposasas/genética
19.
Insect Mol Biol ; 14(5): 547-53, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16164610

RESUMEN

We isolated multiple copies of mariner-like element (MLE) from the pink bollworm (PBW), Pectinophora gossypiella, a key lepidopteran cotton pest. Although all the MLE sequences contain multiple mutations accumulated in their transposase coding region, the consensus sequence revealed a putative ancestral transposase encoding 339 amino acid residues with a D,D(34)D motif, and 36 bp inverted terminal repeats, belonging to the cecropia subfamily, and most similar to the MLE found in Antheraea species. Examining six different pink bollworm populations, we conclude that the MLE in PBW described in this study are ancient and are undergoing the process of accumulating inactivating mutations. This conclusion is supported by the patterns of polymorphisms revealed by genomic Southern hybridization, transposable element displays, and sequences from multiple MLE.


Asunto(s)
Proteínas de Insectos/genética , Mariposas Nocturnas/genética , Transposasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Secuencia de Consenso , Elementos Transponibles de ADN/genética , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido
20.
J Econ Entomol ; 97(3): 757-63, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15279249

RESUMEN

The recent spread of the plant pathogenic bacterium Xylclla fastidiosa Wells et al. by an invasive vector species, Homalodisca coagulata Say, in southern California has resulted in new epidemics of Pierce's disease of grapevine. Our goal is to develop an efficient method to detect low titers of X. fastidiosa in H. coagulata that is amenable to large sample sizes for epidemiological studies. Detection of the plant pathogenic bacterium X. fastidiosa in its insect vector is complicated by low titers of bacteria, difficulty in releasing it from the insect mouthparts and foregut, and the presence of substances in the insect that inhibit polymerase chain reaction (PCr). To select the optimal protocol for DNA extraction to be used with PCR, we compared three standard methods and 11 commercially available kits for relative efficiency of X. fastidiosa DNA extraction in the presence of insect tissue. All of the protocols tested were proficient at extracting DNA from pure bacterial culture (1 x 10(5) cells), and all but one protocol successfully extracted sufficient bacterial DNA in the presence of insect tissue. Three DNA extraction techniques, immunomagnetic separation, the DNeasy Tissue kit (Qiagen, Hercules, CA), and Genomic DNA Purification kit (Fermentus, Hanover, MD), were compared more closely using a dilution series of X. fastidiosa (5000-0 cells) with and without insect tissue present. The DNeasy Tissue kit was the best kit tested, allowing detection of 5 x 10(3) X. fastidiosa cells with an insect head background.


Asunto(s)
ADN Bacteriano/aislamiento & purificación , Hemípteros/microbiología , Xylella/genética , Animales , Insectos Vectores/microbiología , Reacción en Cadena de la Polimerasa/métodos , Vitis/microbiología
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