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1.
Insect Mol Biol ; 24(2): 191-202, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25528896

RESUMEN

Evidence is emerging that some proteins secreted by gall-forming parasites of plants act as effectors responsible for systemic changes in the host plant, such as galling and nutrient tissue formation. A large number of secreted salivary gland proteins (SSGPs) that are the putative effectors responsible for the physiological changes elicited in susceptible seedling wheat by Hessian fly, Mayetiola destructor (Say), larvae have been documented. However, how the genes encoding these candidate effectors might respond under field conditions is unknown. The goal of this study was to use microarray analysis to investigate variation in SSGP transcript abundance amongst field collections from different geographical regions (southeastern USA, central USA, and the Middle East). Results revealed significant variation in SSGP transcript abundance amongst the field collections studied. The field collections separated into three distinct groups that corresponded to the wheat classes grown in the different geographical regions as well as to recently described Hessian fly populations. These data support previous reports correlating Hessian fly population structure with micropopulation differences owing to agro-ecosystem parameters such as cultivation of regionally adapted wheat varieties, deployment of resistance genes and variation in climatic conditions.


Asunto(s)
Dípteros/genética , Proteínas de Insectos/genética , Proteínas y Péptidos Salivales/genética , Animales , Dípteros/metabolismo , Etiquetas de Secuencia Expresada , Expresión Génica , Interacciones Huésped-Parásitos , Israel , Larva/genética , Larva/metabolismo , Datos de Secuencia Molecular , Filogenia , Glándulas Salivales/metabolismo , Triticum/parasitología , Estados Unidos
2.
Arthropod Struct Dev ; 43(2): 183-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24291672

RESUMEN

Obligate bacterial endosymbionts are common, influential associates of arthropods, and are often found in specific organs termed bacteriomes. Three dimensional images of bacteriomes of the leafhopper Orosius albicinctus (Hemiptera: Cicadellidae) were reconstructed from synchrotron-based X-ray micro-computed tomography (CT). Results show that bilateral bacteriomes are located between the first and second abdominal tergites, are mushroom-shaped and consist two different types of tissue. Fluorescence in situ hybridization reveals that the primary bacterial symbiont Sulcia muelleri is in the 'cap' part of the of organ. The technique allows a noninvasive, in situ, means of visualizing bacteriomes and will facilitate understanding their form and function.


Asunto(s)
Hemípteros/microbiología , Sincrotrones , Microtomografía por Rayos X/métodos , Animales , Microbiota
3.
Bull Entomol Res ; 102(6): 632-43, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22564785

RESUMEN

Samples of a dipteran pest of wheat were tested to confirm identity, describe local populations and suggest the use of deploying resistance (R) genes in wheat cultivars for control of Mayetiola destructor, Hessian fly (HF). Morphological evaluation of adults and a free-choice oviposition preference test documenting that females overwhelmingly preferred to oviposit on wheat instead of barley supported they were HF. Using the cytochrome c oxidase subunit I (coxI), the Barcoding Region, nine haplotypes were revealed. Two were found only in the Israeli collections and averaged 3% sequence divergence compared to the other seven haplotypes found in the United States, Israel and Syria. In evaluations of virulence, the Israeli HF in culture was virulent to 11 of the 19 (R) genes tested, and complementation analysis documented that, for four of the R genes tested, the Israeli HF shared loci for virulence with HF from the United States. Levels of HF infestation at seven Israeli fields were at least at the 5-8% level, which historically has indicated a significant yield loss. Microsatellite genotyping of the five HF collections from Israel revealed mixed populations in Israel that are distinctly separate from the single population in Syria.


Asunto(s)
Dípteros/fisiología , Triticum/genética , Animales , Código de Barras del ADN Taxonómico , Dípteros/anatomía & histología , Dípteros/patogenicidad , Femenino , Prueba de Complementación Genética , Técnicas de Genotipaje , Herbivoria , Masculino , Repeticiones de Microsatélite , Oviposición , Densidad de Población , Virulencia
4.
Exp Appl Acarol ; 45(1-2): 29-37, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18584132

RESUMEN

The efficacy of Neoseiulus californicus (a generalist predatory mite) for the biological control of Tetranychus urticae, was compared to release of Phytoseiulus persimilis (a specialist predatory mite) and an acaricide treatment in sweet pepper plants grown in greenhouse tunnels in a hot and arid climate. To ensure uniform pest populations, spider mites were spread on pepper plants in two seasons; a natural infestation occurred in one season. Predators were released prophylactically and curatively in separate tunnels when plants were artificially infested with spider mites, and at low and moderate spider mite populations when infestations occurred naturally. Although spider mite populations did not establish well the first year, fewer spider mites were recovered with release of N. californicus than with all other treatments. In the second year, spider mites established and the prophylactic release of N. californicus compared favorably with the acaricide-treated plants. In the course of monitoring arthropod populations, we observed a significant reduction in western flower thrips (Frankliniella occidentalis) populations in tunnels treated with N. californicus as compared with non-treated control tunnels. Our field trials validate results obtained from potted-plant experiments and confirm that N. californicus is a superior spider mite predator at high temperatures and low humidities.


Asunto(s)
Capsicum , Calor , Ácaros/fisiología , Control Biológico de Vectores , Tetranychidae/fisiología , Animales , Humedad , Conducta Predatoria
5.
J Econ Entomol ; 97(5): 1581-6, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15568346

RESUMEN

Aqueous extracts from two plants, Urginea maritima L. (Liliaceae) and Euphorbia myrsinites L. (Euphorbiaceae), were tested for their insecticidal activity against the leafminer Liriomyza trifolii (Burgess) on infested tomato, Lycopersicon esculentum Mill., plants in the laboratory and field. Two grams of plant material was extracted with 100 ml of water and then diluted 1:100, 1:50, and 1:25 with distilled water. Diluted plant extract was either applied to the infested tomato leaves or by soil drench and was compared with foliar application of cyromazine. All dilutions of both plant extracts caused significant control of the leafminer larvae and maintained populations below those of the nontreated control plants in all trials. Only at the most concentrated dilutions (1:25) were the plant extracts statistically similar to the cyromazine treatment. Furthermore, greenhouse yields from all of the foliar treatments were statistically similar to the cyromazine treatment and significantly better than the nontreated control. Four species of leafminer parasitoids were found in the greenhouse; however, the percentage of parasitism was significantly less in all treated replicates than in the nontreated control replicates. Aqueous extracts from these two plant extracts exhibited both translaminar and systemic activity and are potential candidates as new organic insecticides.


Asunto(s)
Dípteros/efectos de los fármacos , Extractos Vegetales/farmacología , Solanum lycopersicum/parasitología , Animales , Drimia , Euphorbia , Larva/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Hojas de la Planta , Suelo
6.
Nucleosides Nucleotides Nucleic Acids ; 20(4-7): 1067-78, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11562960

RESUMEN

Cyclin-dependent kinases (CDKs) belong to a class of enzymes that control the ability of a cell to enter into and proceed through the cell division cycle. Using purine as a scaffold, we have synthesized a number of nanomolar inhibitors of CDK-2/cyclin E. In this report, the synthesis of a series of piperidine-substituted purine analogs will be presented, as well as some of their in vitro and in vivo biological effects.


Asunto(s)
Adenina/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Quinasas CDC2-CDC28 , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Piperidinas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Purinas/síntesis química , Purinas/farmacología , Adenina/análogos & derivados , Adenina/síntesis química , Animales , Quinasa 2 Dependiente de la Ciclina , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células HT29/efectos de los fármacos , Humanos , Ratones , Ratones Desnudos , Piperidinas/síntesis química , Relación Estructura-Actividad , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Exp Appl Acarol ; 25(3): 217-24, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11523917

RESUMEN

Broad mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), is a serious plant pest in tropical and subtropical regions. Phoretic associations between broad mite and two genera of whiteflies (Insecta: Homoptera: Aleyrodidae). namely Bemisia and Trialeurodes, have been reported from different parts of the world. Our purpose was to determine the specificity of the association between the mite and its phoretic hosts. Two host plants, potatoes and cucumbers, were used to study these relationships in the laboratory. Insects frozen for 24 h were used as potential phoretic hosts in all experiments. Attachment levels were monitored by counting the number of mites attached to each insect. All tests were conducted for 4-6 h. as attachment to Bemisia tabaci on potato shoots leveled off after 4 h, increasing only marginally after 8 h. Attachment levels to thrips (the western flower thrips, Frankliniella occidentalis) and to allate aphids (Myzus persicae) was negligible relative to the attachment to B. tabaci. Broad mite also attached to the whiteflies Dialeurodes citri, Aleyrodes singularis and Trialeurodes lauri, the latter being the least attractive species (including B. tabaci). Washing B. tabaci with pentane greatly reduced attachment. Using cucumbers as hosts did not substantially change the general trend, but attachment levels were lower. The phoretic relationship between broad mite and its insect hosts appears to be specific to whiteflies, with some whiteflies having a higher potential as phoretic hosts.


Asunto(s)
Hemípteros , Ácaros , Animales , Femenino
8.
J Pediatr Surg ; 36(7): 1054-6, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11431776

RESUMEN

Intraabdominal coccidioidomycosis is a very rare entity and usually responds to medical therapy. Operative intervention is reserved for diagnosis or drainage of localized collections. With biliary coccidioidomycosis, medical treatment appears to be ineffective, and biliary tract drainage is necessary for optimal management. A case of coccidioidomycosis in the gallbladder and biliary tree is described and the literature reviewed.


Asunto(s)
Enfermedades de las Vías Biliares/diagnóstico , Coccidioidomicosis/diagnóstico , Conductos Biliares Extrahepáticos/diagnóstico por imagen , Conductos Biliares Extrahepáticos/patología , Enfermedades de las Vías Biliares/cirugía , Niño , Colangiopancreatografia Retrógrada Endoscópica , Colecistectomía , Colecistografía , Coccidioidomicosis/cirugía , Vesícula Biliar/patología , Humanos , Enfermedades Pulmonares Fúngicas/diagnóstico , Masculino , Stents , Tomografía Computarizada por Rayos X
9.
Nucleosides Nucleotides ; 18(10): 2175-91, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10616724

RESUMEN

Three novel nucleosides 1, 2, and 3 were prepared that contained side chains at the 2-position of adenosine. Compound 1 was shown to be the most selective A2a receptor agonist reported to date having an A1/A2 ratio of 2400. In addition, compound 1 was shown to reduce blood pressure in rats and dogs with only minimal effects on heart rate.


Asunto(s)
Adenosina/análogos & derivados , Nucleósidos de Purina/síntesis química , Agonistas del Receptor Purinérgico P1 , Adenosina/síntesis química , Adenosina/química , Adenosina/metabolismo , Adenosina/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Perros , Frecuencia Cardíaca/efectos de los fármacos , Hipertensión/fisiopatología , Técnicas In Vitro , Nucleósidos de Purina/química , Nucleósidos de Purina/metabolismo , Nucleósidos de Purina/farmacología , Ratas , Receptor de Adenosina A2A
10.
J Am Acad Child Adolesc Psychiatry ; 35(8): 1042-9, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8755801

RESUMEN

OBJECTIVE: To examine the hypothesis that an association exists between severe asthma and familial affective and anxiety disorders. METHOD: A parent, usually the mother, of 62 adolescents admitted to a tertiary care asthma center was administered the Family History-Research Diagnostic Criteria Interview. Lifetime prevalence rates of psychiatric disorders in first-degree relatives were compared with previously reported rates. RESULTS: In relatives of asthmatic adolescents, rates for depression, mania (females only), substance abuse (males only), and antisocial personality disorder were significantly higher than the rates in the non-ill comparison sample. Rates for substance abuse (males only) and antisocial personality disorder were higher than the rates for relatives of the depressed comparison sample. Rates for anxiety disorders were not higher than rates in epidemiological samples. Rates of attention-deficit hyperactivity disorder (females only) and posttraumatic stress disorder in relatives were higher than in community samples. CONCLUSIONS: These results support the presence of a link between severe asthma and familial affective disorders, posttraumatic stress disorder, antisocial personality disorder, and substance abuse. Whether these disorders are genetically associated with asthma or represent an association with severe asthma because of environmental effects on the growing child is discussed.


Asunto(s)
Asma/psicología , Familia/psicología , Trastornos Mentales/psicología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Padres/psicología
11.
Acad Psychiatry ; 15(3): 132-6, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24449111

RESUMEN

Part of child psychiatry's recruitment problem stems from defections among medical students who were planning careers in child psychiatry when they entered medical school The authors present data showing that between 1974 and 1984 University of Maryland Medical School graduates specializing in psychiatry were more than twice as likely to enter fellowships in child and adolescent psychiatry if they were participants in the Combined Accelerated Program in Psychiatry (CAPP) as medical students. The CAPP, a 4-year medical school track that contains a strong child psychiatry component, appears to prevent the erosion of students' interest in child psychiatry.

12.
Steroids ; 55(9): 378-82, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2281513

RESUMEN

Increased mineralocorticoid activity has been associated with elevated urinary levels of 19-nordeoxycorticosterone in several forms of experimental and human hypertension. Biosynthesis of 19-norsteroids involves hydroxylation of the C-19 methyl group. We synthesized the 4-hydroxy analogs of deoxycorticosterone, deoxycorticosterone acetate, progesterone, and androstenedione and evaluated them as inhibitors of deoxycorticosterone 11 beta/19-hydroxylase using hamster adrenal mitochondrial preparations. These 4-hydroxy analogs were inhibitors of this P 450 hydroxylase, with approximately 10 times weaker affinity than their respective natural substrates. 4-Hydroxydeoxycorticosterone was the most potent inhibitor evaluated in this study. The half-maximal inhibitory concentration of deoxycorticosterone hydroxylation was 5 microM, 15 microM, more than 50 microM, and 14 microM, respectively, for the above compounds.


Asunto(s)
Glándulas Suprarrenales/enzimología , Esteroide Hidroxilasas/antagonistas & inhibidores , Animales , Cricetinae , Técnicas In Vitro , Masculino , Mesocricetus , Mitocondrias/enzimología , Estructura Molecular , Esteroides/farmacología
13.
Pharmacology ; 40(5): 271-6, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2177202

RESUMEN

[(Octahydro-2-oxo-7-tetradecylidene-2H-1-benzopyran-8-yl)thio]acet ic acid (MDL 43,291) is a novel leukotriene (LT) receptor antagonist. It is a competitive antagonist of LTD4 (pA2 = 6.7) and LTE4 (pA2 = 6.7) and an apparent noncompetitive inhibitor of LTC4 ('pseudo' pA2 = 6.8) in the longitudinal muscle of the guinea pig ileum. At concentrations that effectively antagonize peptidoleukotriene-induced contractions, MDL 43,291 does not antagonize histamine, carbachol or substance P. In vivo, 10-30 mg/kg MDL 43,291, given intravenously, effectively inhibits increases in insufflation pressure induced by 100 ng/kg i.v. LTD4. This compound is a prototype of a novel class of leukotriene receptor antagonists that may be useful in the treatment of bronchial asthma and related disorders.


Asunto(s)
Lactonas/farmacología , Receptores Inmunológicos/antagonistas & inhibidores , Sulfuros/farmacología , Animales , Cromonas/farmacología , Relación Dosis-Respuesta a Droga , Cobayas , Íleon/efectos de los fármacos , Íleon/fisiología , Inyecciones Intravenosas , Leucotrieno E4 , Masculino , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Receptores de Leucotrienos , SRS-A/administración & dosificación , SRS-A/análogos & derivados , SRS-A/antagonistas & inhibidores , SRS-A/farmacología
14.
J Pharm Sci ; 78(11): 937-43, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2559964

RESUMEN

A series of substituted 3,4-dihydro-2H-1,4-thiazines inhibit 5-lipoxygenase from rat leukocytes and exhibit submicromolar IC50 values. A novel synthesis of these compounds was developed based on the formation of hydroxymethyleneamine 13 and its cyclization to the title compounds. The dihydrothiazines have low oxidation potentials, typically E1/2 is near 0.3 V, and a representative compound reduces Fe(III)(phen)3, with k = 10(5) M-1s-1. We propose that these lipophilic compounds bind to 5-lipoxygenase and reduce the iron in the active site, thus inactivating the enzyme.


Asunto(s)
Inhibidores de la Lipooxigenasa , Tiazinas/farmacología , Animales , Fenómenos Químicos , Química , Técnicas In Vitro , Leucotrieno B4/metabolismo , Peróxidos Lipídicos/farmacología , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Ratas
15.
J Urol ; 142(1): 52-5, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2733109

RESUMEN

A technique is described that has successfully permitted prompt atraumatic urethral realignment and stenting after prostatomembranous urethral disruption in 7 patients.


Asunto(s)
Uretra/lesiones , Cateterismo Urinario/métodos , Heridas no Penetrantes/terapia , Adulto , Catéteres de Permanencia , Cistoscopía , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Rotura
16.
J Urol ; 140(6): 1397-9, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3143017

RESUMEN

Historically, survival of patients with adult pelvic sarcoma of the bladder and prostate has been poor. Between November 1974 and November 1984 we treated 11 patients with leiomyosarcoma: 7 with primary bladder and 4 with prostate tumors. Patients with nonbulky disease underwent surgical resection and were observed if the margins and nodes were negative. Patients with positive surgical margins or nodes were treated adjunctively with external beam radiotherapy, 4,500 to 5,000 rad, and chemotherapy. Patients with bulky disease were treated with preoperative chemotherapy with or without radiotherapy followed by an exenterative operation. Of the 11 patients 9 are without evidence of disease with a mean followup of 61 months (range 35 to 96 months). One patient was lost to followup after 4 months and 1 died of disease after 11 months. Three patients with rhabdomyosarcoma were treated and 1 had no evidence of disease 24 months after therapy. Two patients died at 4 and 18 months.


Asunto(s)
Leiomiosarcoma/terapia , Rabdomiosarcoma/terapia , Neoplasias de la Vejiga Urinaria/terapia , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Dosificación Radioterapéutica , Radioterapia de Alta Energía , Vejiga Urinaria/cirugía
17.
Endocrinology ; 119(3): 959-66, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3732173

RESUMEN

(5 alpha, 20S)-4-Diazo-21-hydroxy-20-methylpregnan-3-one, a mechanism-based inhibitor of testosterone 5 alpha-reductase, produced pronounced and long lasting inhibition of the enzyme in the prostate and preputial glands when administered orally to rats. Administration of the inhibitor to castrate rats bearing testosterone implants produced inhibition of growth of the prostate, seminal vesicles,and preputial glands, but had no effect on growth of the levator ani muscle. (5 alpha-20S)-4-Diazo-21-hydroxy-20-methylpregnan-3-one did not antagonize growth of the accessory sex organs induced by 5 alpha-dihydrotestosterone (5 alpha-DHT). The inhibitor thus produced a pure 5 alpha-reductase deficiency in the rat without detectable receptor-level antagonism, and with consequences similar to those occurring at puberty in the 5 alpha-reductase-deficient human male: reduction of 5 alpha-DHT-mediated processes and maintenance of those mediated by testosterone. The results emphasize the importance of the enzymatic profiles of individual organs in determining selective response to testosterone or 5 alpha-DHT. Evidence is presented which indicates that the testes are the source of circulating 5 alpha-DHT in the immature rat.


Asunto(s)
3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/deficiencia , Dihidrotestosterona/sangre , Testosterona/sangre , Inhibidores de 5-alfa-Reductasa , Animales , Dihidrotestosterona/metabolismo , Estradiol/metabolismo , Genitales Masculinos/efectos de los fármacos , Genitales Masculinos/enzimología , Masculino , Orquiectomía , Pregnanolona/análogos & derivados , Pregnanolona/farmacología , Progesterona/metabolismo , Ratas , Ratas Endogámicas , Receptores Androgénicos/metabolismo
18.
J Med Chem ; 28(6): 831-3, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4009607

RESUMEN

20-(Hydroxymethyl)-4-methyl-4-aza-2-oxa-5 alpha-pregnan-3-one and the corresponding 3-thione were synthesized with use of 20-(hydroxymethyl)-4-methyl-4-aza-5 alpha-pregnan-3-one as the starting material. The compounds were tested in vitro for inhibition of testosterone 5 alpha-reductase and found to be weak inhibitors with Ki's in the 10(-7) range.


Asunto(s)
Inhibidores de 5-alfa-Reductasa , Oxidorreductasas/antagonistas & inhibidores , Pregnanos/síntesis química , Esteroides Heterocíclicos/síntesis química , Animales , Inhibidores Enzimáticos/síntesis química , Técnicas In Vitro , Cinética , Masculino , Pregnanos/farmacología , Próstata/enzimología , Ratas , Esteroides Heterocíclicos/farmacología
19.
Steroids ; 45(3-4): 357-74, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3834657

RESUMEN

Androst-4-en-3-one analogs incorporating a trimethylsilyl or a trimethylsilylmethyl group at C-1, C-2 or C-19 were prepared and evaluated as inhibitors of aromatase. Only 10-[1-hydroxy-2-(trimethylsilyl)ethyl]estr-4-ene-3,17-dione inhibited human placental aromatase. Enzyme kinetic analysis revealed competitive inhibition [apparent dissociation constant (Ki) of 562 +/- 12 nM] associated with marginal time-dependent inhibition.


Asunto(s)
Androstenoles/síntesis química , Inhibidores de la Aromatasa , Placenta/enzimología , Silicio/síntesis química , Compuestos de Trimetilsililo/síntesis química , Androstenoles/farmacología , Unión Competitiva , Fenómenos Químicos , Química , Femenino , Humanos , Indicadores y Reactivos , Cinética , Espectroscopía de Resonancia Magnética , Embarazo , Relación Estructura-Actividad , Compuestos de Trimetilsililo/farmacología
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