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1.
J Econ Entomol ; 108(1): 157-65, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26470116

RESUMEN

Fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae); corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae); southwestern corn borer, Diatraea grandiosella Dyar (Lepidoptera: Crambidae); sugarcane borer, Diatraea saccharalis F. (Lepidoptera: Crambidae); and lesser cornstalk borer, Elasmopalpus lignosellus Zeller (Lepidoptera: Pyralidae), are lepidopteran pests of corn, Zea mays L., in the southern United States. Blended refuge for transgenic plants expressing the insecticidal protein derivative from Bacillus thuringiensis (Bt) has recently been approved as an alternative resistance management strategy in the northern United States. We conducted a two-year study with 39 experiments across 12 states in the southern United States to evaluate plant injury from these five species of Lepidoptera to corn expressing Cry1F and Cry1Ab, as both single and pyramided traits, a pyramid of Cry1Ab×Vip3Aa20, and a pyramid of Cry1F×Cry1Ab plus non-Bt in a blended refuge. Leaf injury and kernel damage from corn earworm and fall armyworm, and stalking tunneling by southwestern corn borer, were similar in Cry1F×Cry1Ab plants compared with the Cry1F×Cry1Ab plus non-Bt blended refuge averaged across five-plant clusters. When measured on an individual plant basis, leaf injury, kernel damage, stalk tunneling (southwestern corn borer), and dead or injured plants (lesser cornstalk borer) were greater in the blended non-Bt refuge plants compared to Cry1F×Cry1Ab plants in the non-Bt and pyramided Cry1F×Cry1Ab blended refuge treatment. When non-Bt blended refuge plants were compared to a structured refuge of non-Bt plants, no significant difference was detected in leaf injury, kernel damage, or stalk tunneling (southwestern corn borer). Plant stands in the non-Bt and pyramided Cry1F×Cry1Ab blended refuge treatment had more stalk tunneling from sugarcane borer and plant death from lesser cornstalk borer compared to a pyramided Cry1F×Cry1Ab structured refuge treatment. Hybrid plants containing Cry1F×Cry1Ab within the pyramided Cry1F×Cry1Ab blended refuge treatment had significantly less kernel damage than non-Bt structured refuge treatments. Both single and pyramided Bt traits were effective against southwestern corn borer, sugarcane borer, and lesser cornstalk borer.


Asunto(s)
Agricultura/métodos , Proteínas Bacterianas , Endotoxinas , Proteínas Hemolisinas , Herbivoria , Lepidópteros , Animales , Toxinas de Bacillus thuringiensis , Spodoptera
2.
Sci Rep ; 12(1): 13580, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35945334

RESUMEN

The fall armyworm (Spodoptera frugiperda) is a highly polyphagous lepidopteran pest of relevant food and fiber staple crops. In the Americas, transgenic corn and cotton producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have controlled and reduced the damage caused by S. frugiperda. However, cases of field-evolved S. frugiperda resistance to Bt corn producing the Cry1F insecticidal protein have been documented in North and South America. When characterized, field resistance to Cry1F is linked to insertions and mutations resulting in a modified or truncated ABC transporter subfamily C2 (SfABCC2) protein that serves as Cry1F receptor in susceptible S. frugiperda. In this work, we present detection of a large genomic deletion (~ 8 kb) affecting the SfABCC2 and an ABC transporter gene subfamily 3 -like gene (SfABCC3) as linked to resistance to Cry1F corn in a S. frugiperda strain from Florida (FL39). Monitoring for this genomic deletion using a discriminatory PCR reaction in field-collected S. frugiperda moths detected individuals carrying this allele in Florida, but not in surrounding states. This is the first report of a large genomic deletion being involved in resistance to a Bt insecticidal protein.


Asunto(s)
Bacillus thuringiensis , Insecticidas , Transportadoras de Casetes de Unión a ATP/genética , Animales , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Endotoxinas/genética , Florida , Genómica , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacología , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Plantas Modificadas Genéticamente/genética , Spodoptera/metabolismo , Zea mays/genética , Zea mays/metabolismo
3.
J Econ Entomol ; 109(4): 1859-71, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27329627

RESUMEN

Blended refuge for transgenic plants expressing Bacillus thuringiensis (Bt) toxins has been approved in the northern United States as a resistance management strategy alternative to a structured refuge. A three-year study (2012-2014) was conducted with 54 trials across nine states in the southern United States to evaluate plant injury from lepidopteran pests of corn and yield in a corn hybrid expressing Cry1F × Cry1Ab × Vip3Aa20 (Pioneer Brand Optimum Leptra) planted as a pure stand and in refuge blends of 5, 10, and 20% in both early and late plantings. Injury by corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), was generally proportional to the percentage of non-Bt corn within each refuge blend. Across locations, ear injury in plots with 100% Cry1F × Cry1Ab × Vip3Aa20 (Optimum Leptra) corn ranged from no injury to a maximum of 0.42 cm(2) per ear in Mississippi in 2013. Leaf injury ratings in 100% non-Bt plots in early and late planted trials in 2014 were 86- and 70-fold greater than in 100% Cry1F × Cry1Ab × Vip3Aa20 (Optimum Leptra) plots. Plants in plots with blended refuges had significantly greater leaf injury in 2012 (5, 10, and 20% refuge blends), in the early-planted corn in 2013 (10 and 20% only), and in both early- and late-planted corn in 2014 (20% only) as compared with leaf injury in a pure stand of Cry1F × Cry1Ab × Vip3Aa20 (Optimum Leptra) seen during these years. Corn ears in plots with blended refuges also had significantly greater area of kernels injured in 2012 (5, 10, and 20%), in early- and late-planted corn in 2013 (5, 10, and 20%), and in early (10 and 20% only)- and late-planted corn (5, 10, and 20%) in 2014 as compared with ear injury in a pure stand of Cry1F × Cry1Ab × Vip3Aa20 (Optimum Leptra) seen during these years. Infestations of southwestern corn borer, Diatraea grandiosella Dyar (Lepidoptera: Crambidae), were also significantly reduced by Cry1F × Cry1Ab × Vip3Aa20 (Optimum Leptra). Despite these differences in injury, yield averaged across locations varied among refuge blends only in the late-planted trials in 2013, with greater yields in the 0% refuge blend than in the 20% blend; however, when examining yield separately by location, only two of nine locations had higher yields in the 100% Bt plots than in any of the blended refuge plots. As a complement to studying the contribution of blended refuge to delaying resistance, quantifying injury and yield in a range of refuge blends is a necessary step to provide management information on the range of lepidopteran pests that occur in the southern United States.


Asunto(s)
Bacillus thuringiensis/química , Proteínas Bacterianas/farmacología , Toxinas Bacterianas/farmacología , Mariposas Nocturnas/fisiología , Zea mays/fisiología , Animales , Bacillus thuringiensis/genética , Resistencia a los Insecticidas , Control Biológico de Vectores , Estados Unidos , Zea mays/genética , Zea mays/crecimiento & desarrollo
4.
Obstet Gynecol ; 76(4): 656-9, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2216198

RESUMEN

The purpose of this study was to determine the efficacy and safety of 0.5% podofilox solution (Condylox) for the treatment of genital warts in women. Thirty-seven women with anogenital warts applied the solution to the surface of these warts twice daily for 3 days, followed by 4 drug-free days. A minimum of two and a maximum of four treatment cycles were given. The subjects were evaluated weekly for the first 4 weeks and again at 6 and 10 weeks. At the end of 10 weeks, the mean number of warts per patient was reduced from 6.27 to 1.1, and half of the patients were completely cleared of warts. Only eight of 37 subjects (21.6%) developed new warts during the study period. Approximately 15% of patients reported "severe" local reactions to the treatment after the first treatment cycle, but this was reduced to only 5% by the last treatment cycle. During the same period, the patients reporting no side effects increased from 44 to 86%. The only woman who discontinued the study did so because of dizziness and epigastric discomfort, probably unrelated to drug use. Thus, 0.5% podofilox solution appears to be an effective treatment for condylomata acuminata, with acceptable side effects that are local and temporary.


Asunto(s)
Condiloma Acuminado/tratamiento farmacológico , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Podofilotoxina/administración & dosificación , Administración Tópica , Adulto , Animales , Esquema de Medicación , Femenino , Humanos , Podofilotoxina/uso terapéutico , Factores de Tiempo
5.
Am J Ophthalmol ; 98(1): 32-6, 1984 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-6377901

RESUMEN

Of two patients with discoid lupus erythematosus with eyelid involvement, one, a 42-year-old man, had a one-year history of persistent periorbital edema and a violaceous discoloration as the sole manifestation. Although treatment with corticosteroids and antihistamines failed to produce improvement, the patient had an excellent clinical response to systemic hydroxychloroquine therapy. Histologic examination with immunofluorescent staining demonstrated deposition of immunoglobulins at the dermoepidermal junction. The second patient, a 37-year-old woman, had a hyperpigmented lesion on her forearm as the initial symptom but later developed similar lesions elsewhere, including her lower eyelid. Treatment with hydroxychloroquine again produced an excellent response.


Asunto(s)
Enfermedades de los Párpados/patología , Lupus Eritematoso Discoide/patología , Adulto , Edema/patología , Enfermedades de los Párpados/tratamiento farmacológico , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Hidroxicloroquina/uso terapéutico , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Lupus Eritematoso Discoide/tratamiento farmacológico , Linfocitos/patología , Masculino , Piel/patología
6.
Dermatol Clin ; 6(3): 443-56, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3048826

RESUMEN

The dermatologic findings indicative of STDs are invaluable clues to accurate diagnosis. The sexual consorts of confirmed and suspected STD patients must be promptly evaluated and treated of disease spread is to be curtailed. It is important to remember that some patients will present with more than one STD (Fig. 36). Sexually transmitted diseases in black patients may be atypical or exaggerated because of the host's unique tissue response. Every patient should be counseled regarding "safer sex."


Asunto(s)
Población Negra , Enfermedades de Transmisión Sexual/etnología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Enfermedades de Transmisión Sexual/complicaciones , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/terapia , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/etiología , Enfermedades de la Piel/terapia
7.
Dermatol Clin ; 15(2): 221-32, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9098632
8.
Cutis ; 30(4): 536-7, 541, 547, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6216074

RESUMEN

Twenty-eight patients with severe cutaneous infections received cefoperazone, 2 grams intramuscularly twice a day for seven days. A wide range of gram-positive and gram-negative pathogens were isolated from admission cultures. All patients showed rapid clinical improvement. Two patients did not complete the full course of therapy because of intervening medical problems unrelated to the antibiotic. No significant side effects were noted. Relapses or reinfections occurred in two patients. In conclusions, cefoperazone is a safe and effective antibiotic for use in skin infections requiring parenteral therapy.


Asunto(s)
Disuasivos de Alcohol/uso terapéutico , Cefalosporinas/uso terapéutico , Enfermedades Cutáneas Infecciosas/tratamiento farmacológico , Disuasivos de Alcohol/administración & dosificación , Cefoperazona , Celulitis (Flemón)/tratamiento farmacológico , Cefalosporinas/administración & dosificación , Niño , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Dermatosis del Pie/tratamiento farmacológico , Humanos , Inyecciones Intramusculares , Pseudomonas/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/tratamiento farmacológico
9.
Environ Entomol ; 43(6): 1641-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25290163

RESUMEN

Climate variability is expected to have an influence on the population of Hessian fly, Mayetiola destructor Say (Diptera: Cecidomyiidae), a serious insect pest of winter wheat in the southeastern United States. This study had two objectives: 1) to examine the effects of El Niño-Southern Oscillation (ENSO) on Hessian fly infestation and 2) to develop a weather-based Hessian fly infestation model for wheat yield loss prediction. At least 20 years of Hessian fly infestation and wheat yield records from two locations in South Georgia were used for this study. The yearly values of infestation were separated by ENSO phase and tested to assess the infestation differences across ENSO phases. Each year, yield losses from infestation were calculated by subtracting the yields of resistant varieties from those of susceptible ones. The yield losses were then separated by ENSO phase and tested. Multiple regression analyses were conducted to identify the contribution of monthly weather variables and changes in wheat acreage to Hessian fly infestation. Results showed that Hessian fly infestation and yield losses were greatest during the La Niña and least during the El Niño phase. The weather conditions that significantly increased the risk for infestation were those of the August-February period. The risk of infestation was higher during August-September under wetter, cooler conditions and during October-February under drier, warmer conditions. These findings could help wheat growers reduce the risk of infestation in the years that are expected to have more infestation through the adoption of necessary mitigation measures before the crop season.


Asunto(s)
Agricultura/estadística & datos numéricos , Distribución Animal/fisiología , Dípteros/fisiología , El Niño Oscilación del Sur , Modelos Biológicos , Triticum/parasitología , Agricultura/economía , Animales , Georgia , Dinámica Poblacional , Análisis de Regresión , Especificidad de la Especie
13.
Semin Dermatol ; 13(4): 269-74, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7848821

RESUMEN

This article will review the 1993 STD Treatment Guidelines of particular importance to dermatologic clinical practice. Topics include STD/HIV prevention, management of sexual partners, STD in persons with HIV co-infection, genital ulcer disease (GUD) including syphilis, herpes simplex virus (HSV) infection, lymphogranuloma venereum (LGV) and chancroid, therapy of nongonococcal (NGU) and chlamydial urethritis and cervicitis, gonococcal (GC) infections, HPV infection, hepatitis B virus (HBV) infection, pediculosis pubis, and scabies.


Asunto(s)
Enfermedades de Transmisión Sexual/tratamiento farmacológico , Chancroide/tratamiento farmacológico , Infecciones por Chlamydia/tratamiento farmacológico , Gonorrea/tratamiento farmacológico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Herpes Genital/tratamiento farmacológico , Humanos , Infestaciones por Piojos/tratamiento farmacológico , Linfogranuloma Venéreo/tratamiento farmacológico , Papillomaviridae , Infecciones por Papillomavirus/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Escabiosis/tratamiento farmacológico , Enfermedades de Transmisión Sexual/prevención & control , Sífilis/tratamiento farmacológico , Infecciones Tumorales por Virus/tratamiento farmacológico , Uretritis/tratamiento farmacológico , Uretritis/microbiología
14.
Lancet ; 2(8666): 761-5, 1989 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-2571010

RESUMEN

The prevalence of Epstein-Barr virus (EBV) type B, which was previously found mainly in equatorial Africa, was investigated with the polymerase chain reaction in a population of healthy adults in Memphis, Tennessee. EBV was detected in the throat washings of 34 (22%) of 157 randomly selected donors, 14 (41%) of whom had type B virus and 17 (50%) type A; 3 donors (9%) had both strains. 18 additional adults with human immunodeficiency virus (HIV-1) infection and 6 severely immunocompromised children were also investigated. Results indicated that type B EBV is widespread in nature and may be reactivated by immunodeficiency.


Asunto(s)
ADN Viral/análisis , Herpesvirus Humano 4/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico , Adulto , Secuencia de Bases , Línea Celular , Femenino , Genitales Femeninos/microbiología , Genotipo , Herpesvirus Humano 4/clasificación , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiología , Humanos , Tolerancia Inmunológica , Activación de Linfocitos , Masculino , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Orofaringe/microbiología , Factores de Riesgo , Muestreo , Replicación Viral
16.
J Am Acad Dermatol ; 25(2 Pt 1): 287-99, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1918468

RESUMEN

This update reviews the latest diagnostic and therapeutic methods regarding sexually transmitted diseases caused by bacteria. The following mucocutaneous bacterial disorders will be discussed: syphilis, chancroid, lymphogranuloma venereum, granuloma inguinale, and gonorrhea.


Asunto(s)
Enfermedades Bacterianas de Transmisión Sexual/diagnóstico , Enfermedades Bacterianas de Transmisión Sexual/tratamiento farmacológico , Enfermedades Cutáneas Infecciosas/etiología , Femenino , Infecciones por VIH/complicaciones , Humanos , Masculino , Embarazo , Enfermedades Bacterianas de Transmisión Sexual/complicaciones , Enfermedades Cutáneas Infecciosas/microbiología
19.
J Am Acad Dermatol ; 9(2): 276-7, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6886120
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