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1.
J Econ Entomol ; 115(4): 1069-1075, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35766382

RESUMEN

Aboveground and belowground herbivory can alter host quality and trophic interactions. However, little research has explored the impacts of belowground herbivory on plant virus epidemiology. To understand this interaction in sweetpotato, Ipomoea batatas L. (Lam), we studied the impact of herbivory by sweetpotato weevil, Cylas formicarius elegantulus (Summers), to storage roots on vector herbivore, Myzus persicae (Sulzer), the green peach aphid, and Aphis gossypii Glover, the cotton aphid, feeding behavior (M. persicae and A. gossypii) and population dynamics (M. persicae only as A. gossypii does not colonize sweetpotato). In addition, a nonvector herbivore, Chrysodeixis includens (Walker), the soybean looper, weight gain was included for comparison. Infestations of sweetpotato weevil in storage roots reduced C. includens weight gain and M. persicae intrinsic rate of increase (rm), net reproductive rate (Ro), and finite rate of increase (λ) on aboveground portions of the plant. In probing behaviors related to nonpersistent virus spread (30 min trials), M. persicae probed less often, took longer to reach the first pd (potential drop), had shorter II-3 (intracellular subphase sap ingestion) durations, and had fewer archlets on plants infested with C. formicarius elegantulus. Total phloem duration did not differ between treatments, indicating that the lowered performance of M. persicae on infested plants was not due to discrepancies in probing duration. Results were less clear for A. gossypii. Thus, in sweetpotato, belowground herbivory can alter plant virus vector abundance and behavior. Understanding the mechanisms underlying these changes in behavior could improve plant virus vector integrated pest management.


Asunto(s)
Áfidos , Escarabajos , Ipomoea batatas , Virus de Plantas , Gorgojos , Animales , Herbivoria , Dinámica Poblacional , Aumento de Peso
2.
Osteoarthritis Cartilage ; 29(9): 1346-1350, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33984464

RESUMEN

OBJECTIVE: 'Carbon stress' is a newly found mechanism that links obesity and dysregulated metabolism. It is defined as the cellular accumulation of metabolites during obesity post-translationally modifying metabolic proteins and decreasing their enzymatic activity. The objective of this study was to investigate if 'carbon stress' also occurs in cartilage and contributes to obesity associated OA development. METHODS: We histologically evaluated for OA pathology in wild-type (WT) and hyperphagic mice (Pomc-neuron specific enhancer one deficient, PomcΔ1) that were subjected to standard chow (Chow, n = 6 for both genotypes) or high-fat feeding (HFD, n = 7 for both genotypes). Joints were stained and quantified for 'carbon stress' markers, including succinyl-lysine (SCK), malonyl-lysine (MAK), and acetyl-lysine (ACK). Lastly, we used a mouse model with deletion of Sirt5 (n = 7), which is an enzyme that removes SCK and MAK, to test if changing the abundance of 'carbon stress' would affect OA pathogenesis. RESULTS: Both HFD and Pomc deficiency associated obesity induced cartilage degeneration as well as greater abundance of SCK and MAK in the cartilage. PomcΔ1-HFD mice did not have exacerbated OA pathology as compared to PomcΔ1-Chow mice. ACK was mildly increased in the obese groups comparing to WT-Chow. Sirt5-/- mice developed early-OA like phenotype at 40 weeks of age as characterized by cartilage fibrillation and more hypertrophic chondrocytes. Cartilage from Sirt5-/- mice also had increased SCK and MAK, while ACK remained unchanged comparing to WT mice. CONCLUSION: Our data suggests that carbon stress also occurs in cartilage tissue during obesity and can potentially contribute to obesity-associated OA.


Asunto(s)
Enfermedades de los Cartílagos/etiología , Cartílago/metabolismo , Enfermedades Metabólicas/complicaciones , Enfermedades Metabólicas/metabolismo , Obesidad/complicaciones , Obesidad/metabolismo , Osteoartritis/etiología , Animales , Ratones , Ratones Endogámicos C57BL
3.
J Econ Entomol ; 114(3): 1159-1165, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-33822082

RESUMEN

The rice water weevil, Lissorhoptrus oryzophilus Kuschel, is the most important economic pest of rice in the United States with the ability to substantially reduce rice yields. Stem borers, including the Mexican rice borer, Eoreuma loftini (Dyar), are emerging as more consistent pests in Louisiana and Texas, but the relationship between blanked panicles (whiteheads) caused by stem borer feeding and yield loss is not well understood. A series of field trials was conducted in Louisiana from 2019 to 2020 to determine the relative yield loss by manipulating infestations of both pests with selective insecticides. Results indicate losses from L. oryzophilus infestations are greater than those for E. loftini in early planted rice. In contrast, relative yield losses were approximately equal in later planted rice in 2019, in which E. loftini infestations were high. Additive impacts of the root-feeding L. oryzophilus and the stem-feeding E. loftini were not observed in our study. Linear regression revealed that each increase of one whitehead per square meter is associated with a 1.7% loss in yield. Results from ratoon rice suggest that protection from L. oryzophilus in the main crop also improves yield in the second crop. Collectively, results demonstrate the continued need for effective L. oryzophilus management programs to prevent economic losses. Conversely, findings suggest that benefits of E. loftini control may be minimal in many instances. Control of E. loftini is most likely to be economical under conditions where high populations are anticipated such as in late-planted fields or regions that previously had high infestations.


Asunto(s)
Escarabajos , Oryza , Gorgojos , Animales , Louisiana , México , Texas , Agua
4.
BJOG ; 127(2): 208-216, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31529767

RESUMEN

OBJECTIVE: The objective of this study was to use high-throughput sequencing to describe the vaginal eukaryotic DNA virome in patients undergoing in vitro fertilisation (IVF) to examine associations between the vaginal virome, antibiotic exposure and IVF outcomes. DESIGN: Prospective exploratory study. SETTING: Single academic fertility centre. POPULATION: Subfertile women age 18-43 years undergoing their first IVF cycle with a fresh embryo transfer. METHODS: The primary exposure was prophylactic azithromycin or no azithromycin before IVF. A mid-vaginal swab was obtained at the time of embryo transfer for virome analysis. MAIN OUTCOME MEASURES: The primary outcomes compared between exposure groups were characteristics of vaginal virome and clinical pregnancy rates. Secondary outcomes were virome associations with number of oocytes retrieved, number of blastocysts and implantation rate. RESULTS: Twenty-six women contributed a vaginal swab before embryo transfer. There were no significant differences in IVF outcomes between azithromycin groups. There was no association between viral diversity and clinical pregnancy overall. A higher diversity of herpesviruses and α-papillomaviruses was observed in samples from the azithromycin-treated group compared with the no azithromycin group (P = 0.04). In women that received azithromycin, viral diversity was higher in the group that did not achieve clinical pregnancy compared with those who did (P = 0.06). CONCLUSIONS: We demonstrate that the vaginal eukaryotic virome in women undergoing IVF is associated with antibiotic exposure. Additionally, we demonstrate an inverse trend between viral diversity and pregnancy, with a higher number of viruses detected associated with failure to achieve clinical pregnancy in the azithromycin group. TWEETABLE ABSTRACT: Higher viral diversity is associated with prophylactic antibiotic exposure in subfertile women undergoing IVF.


Asunto(s)
Eucariontes/fisiología , Fertilización In Vitro , Infertilidad/terapia , Microbiota , Vagina/virología , Adulto , Antibacterianos/uso terapéutico , ADN Viral/fisiología , Transferencia de Embrión , Femenino , Herpesviridae , Humanos , Microbiota/genética , Microbiota/inmunología , Papillomaviridae , Embarazo , Estudios Prospectivos , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/inmunología , Análisis de Secuencia de ADN , Vagina/microbiología
5.
Ultrasound Obstet Gynecol ; 56(1): 61-66, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31520557

RESUMEN

OBJECTIVE: Recently, a Delphi procedure was used to establish new criteria for defining fetal growth restriction (FGR). These criteria require clinical validation. We sought to validate the Delphi consensus criteria by comparing their performance with that of our current definition (estimated fetal weight (EFW) < 10th percentile) in predicting adverse neonatal outcome (ANO). METHODS: This was a secondary analysis of data from a prospective cohort study of women referred for fetal growth assessment between 26 and 36 weeks' gestation. The current standard definition of FGR used in our clinical practice is EFW < 10th percentile using Hadlock's fetal growth standard. The Delphi consensus criteria for FGR include either a very small fetus (abdominal circumference (AC) or EFW < 3rd percentile) or a small fetus (AC or EFW < 10th percentile) with additional abnormal Doppler findings or a decrease in AC or EFW by two quartiles or more. The primary outcome was the prediction of a composite of ANO including one or more of: admission to the neonatal intensive care unit, cord pH < 7.1, 5-min Apgar score < 7, respiratory distress syndrome, intraventricular hemorrhage, neonatal seizures or neonatal death. The discriminatory capacities of the two definitions of FGR for composite ANO and delivery of a small-for-gestational-age (SGA) neonate, defined as birth weight < 10th percentile, were compared using area under the receiver-operating-characteristics curve (AUC). The sensitivity, specificity and predictive values of the methods were also compared. RESULTS: Of 1055 pregnancies included in the study, composite ANO occurred in 139 (13.2%). There were only two cases of early FGR (before 32 weeks); therefore, the study focused on late FGR. Our current FGR diagnostic criterion of EFW < 10th percentile was not associated significantly with composite ANO (relative risk (RR), 1.1 (95% CI, 0.6-1.8)), while the Delphi FGR criteria were (RR, 2.0 (95% CI, 1.2-3.3)). Our current definition of FGR showed higher discriminatory ability in the prediction of a SGA neonate (AUC, 0.69 (95% CI, 0.65-0.73)) than did the Delphi definition (AUC, 0.64 (95% CI, 0.60-0.67)) (P = 0.001). The AUCs of both definitions were poor for the prediction of composite ANO, despite slightly improved performance using the Delphi consensus definition of FGR (AUC, 0.53 (95% CI, 0.50-0.55)) compared with that of our current definition (AUC, 0.50 (95% CI, 0.48-0.53)) (P = 0.02). CONCLUSION: The newly postulated criteria for defining FGR based on a Delphi procedure detects fewer cases of neonatal SGA than does our current definition of EFW < 10th percentile, but is associated with a slight improvement in predicting ANO. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Retardo del Crecimiento Fetal/diagnóstico , Recién Nacido Pequeño para la Edad Gestacional , Diagnóstico Prenatal , Adulto , Área Bajo la Curva , Técnica Delphi , Femenino , Humanos , Recién Nacido , Embarazo , Tercer Trimestre del Embarazo , Reproducibilidad de los Resultados
6.
Rev Sci Instrum ; 89(8): 085114, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30184671

RESUMEN

A laboratory-scale device to obtain forming-limit diagram data was designed to utilize the Marciniak and Kuczynski (MK) sample geometry. The design uses a high-resolution photographic camera, automatic trigger, and light-emitting diode (LED) lighting to record the time history of deformation calculated with the digital-image correlation technique. Because the testing device was miniaturized, it was possible to halt the forming experiments at intermediate strains and recrystallize the MK carrier blank. This permits large formability strains to be obtained without cracks developing at the carrier blank's central hole, an advantage over full-size specimens and conventional testing rates. A number of initial experiments were performed on a zinc alloy sheet (Zn-Cu-Ti) over the entire forming-limit range (-0.5 ≤ ε2/ε1 ≤ 1), and the strain fields reduced employing the Bragard criterion to obtain limit strains. These results are compared favorably to previous data of this material obtained with a hemispherical, Nakazima, punch and a circle-grid pattern.

7.
J Dairy Sci ; 101(6): 4906-4913, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29525312

RESUMEN

Concentrations of retinol, α-tocopherol, and major carotenoids in dairy products are often determined simultaneously by liquid chromatography. These compounds have different polarity and solubility; thus, extracting them simultaneously can be difficult and inefficient. In milks with low carotenoid concentrations, the xanthophylls lutein and zeaxanthin may not be completely resolved using common extraction techniques. A simplified method was developed to optimize extraction efficiency and the limit of detection and limit of quantification (LoQ) of lutein and zeaxanthin in bovine milk without decreasing sensitivity to other vitamins or carotenoids. The developed method evaluates lutein, zeaxanthin, ß-carotene, retinol, and α-tocopherol simultaneously by ultra-high performance liquid chromatography-photodiode array detection. Common saponification temperatures (40-60°C) and concentrations of KOH in water (10-50% KOH wt/vol) were evaluated. Multiple solvents were evaluated for optimal xanthophyll extraction (diethyl ether, dichloromethane, hexane, and tetrahydrofuran) following saponification. The limit of detection and LoQ were defined as 3:1 and 10:1 signal-to-noise ratio, respectively. All experiments were performed in triplicate. The optimal saponification procedure was a concentration of 25% KOH at either 40 or 50°C. Saponified extracts solubilized in solutions containing diethyl ether had greater concentrations of lutein- than hexane- or tetrahydrofuran-based solutions, with peak areas above LoQ values. The solution containing diethyl ether solubilized similar concentrations of retinol, α-tocopherol, and ß-carotene when compared with other solutions. The proposed optimized method allows for the simultaneous determination of carotenoids from milk with increased lutein and zeaxanthin sensitivity without sacrificing recovery of retinol, α-tocopherol, and ß-carotene.


Asunto(s)
Alimentación Animal/análisis , Carotenoides/análisis , Cromatografía Líquida de Alta Presión/métodos , Leche/química , Vitaminas/análisis , Xantófilas/análisis , Animales , Bovinos , Luteína/análisis , Vitamina A/análisis , Zeaxantinas/análisis , alfa-Tocoferol/análisis , beta Caroteno/análisis
8.
J Dairy Sci ; 100(10): 7922-7932, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28780108

RESUMEN

Previous research has shown that bleaching affects flavor and functionality of whey proteins. The role of different bleaching agents on vitamin and carotenoid degradation is unknown. The objective of this study was to determine the effects of bleaching whey with traditional annatto (norbixin) by hydrogen peroxide (HP), benzoyl peroxide (BP), or native lactoperoxidase (LP) on vitamin and carotenoid degradation in spray-dried whey protein concentrate 80% protein (WPC80). An alternative colorant was also evaluated. Cheddar whey colored with annatto (15 mL/454 L of milk) was manufactured, pasteurized, and fat separated and then assigned to bleaching treatments of 250 mg/kg HP, 50 mg/kg BP, or 20 mg/kg HP (LP system) at 50°C for 1 h. In addition to a control (whey with norbixin, whey from cheese milk with an alternative colorant (AltC) was evaluated. The control and AltC wheys were also heated to 50°C for 1 h. Wheys were concentrated to 80% protein by ultrafiltration and spray dried. The experiment was replicated in triplicate. Samples were taken after initial milk pasteurization, initial whey formation, after fat separation, after whey pasteurization, after bleaching, and after spray drying for vitamin and carotenoid analyses. Concentrations of retinol, a-tocopherol, water-soluble vitamins, norbixin, and other carotenoids were determined by HPLC, and volatile compounds were measured by gas chromatography-mass spectrometry. Sensory attributes of the rehydrated WPC80 were documented by a trained panel. After chemical or enzymatic bleaching, WPC80 displayed 7.0 to 33.3% reductions in retinol, ß-carotene, ascorbic acid, thiamin, α-carotene, and α-tocopherol. The WPC80 bleached with BP contained significantly less of these compounds than the HP- or LP-bleached WPC80. Riboflavin, pantothenic acid, pyridoxine, nicotinic acid, and cobalamin concentrations in fluid whey were not affected by bleaching. Fat-soluble vitamins were reduced in all wheys by more than 90% following curd formation and fat separation. With the exception of cobalamin and ascorbic acid, water-soluble vitamins were reduced by less than 20% throughout processing. Norbixin destruction, volatile compound, and sensory results were consistent with previous studies on bleached WPC80. The WPC80 colored with AltC had a similar sensory profile, volatile compound profile, and vitamin concentration as the control WPC80.


Asunto(s)
Blanqueadores/farmacología , Carotenoides/farmacología , Colorantes de Alimentos/farmacología , Proteínas de la Leche/efectos de los fármacos , Extractos Vegetales/farmacología , Vitaminas , Proteína de Suero de Leche/efectos de los fármacos , Animales , Bixaceae , Carotenoides/análisis , Queso , Color , Peróxido de Hidrógeno/farmacología , Gusto , Vitaminas/análisis
9.
J Econ Entomol ; 110(2): 479-486, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334296

RESUMEN

Neonicotinoid seed treatments are widely used in agriculture. In rice, Oryza sativa L., in the southern United States, neonicotinoid seed treatments are used to manage early-season populations of the rice water weevil, Lissorhoptrus oryzophilus Kuschel. In addition to their effects on pests, neonicotinoid seed treatments may benefit crop plants directly by increasing plant growth or altering plant responses to stresses. As part of an effort to assess the overall benefits of thiamethoxam seed treatment in rice, rice emergence, growth, and yield were evaluated. In a growth chamber, rice emergence from the soil was 1-2 d more rapid from treated than untreated seeds. These laboratory results were supported by field experiments that revealed higher stand counts from thiamethoxam-treated plots than from untreated plots. Yields from thiamethoxam treatments were no higher than those from untreated plots under conditions in which weevil larvae were absent, a result inconsistent with the hypothesis that thiamethoxam imparts direct yield benefits. In a series of field experiments conducted to compare the relationship between weevil larval densities and rice yields in plots treated with several rates of thiamethoxam or chlorantraniliprole (another widely used seed treatment insecticide), the relationship between weevil density and yield did not differ markedly among both seed treatments. Overall yields from both seed treatments did not differ significantly, despite more effective control in chlorantraniliprole-treated plots. These results provide strong support for effect of thiamethoxam on early-season growth of rice, but only weak support for its direct effect on rice yields.


Asunto(s)
Control de Insectos , Insecticidas , Nitrocompuestos , Oryza/crecimiento & desarrollo , Oxazinas , Tiazoles , Gorgojos , ortoaminobenzoatos , Animales , Control de Insectos/métodos , Larva/crecimiento & desarrollo , Neonicotinoides , Densidad de Población , Semillas/crecimiento & desarrollo , Tiametoxam , Gorgojos/crecimiento & desarrollo
10.
Echo Res Pract ; 2016 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-27686556

RESUMEN

INTRODUCTION: Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is an inherited pathology that can increase the risk of sudden death. Current Task Force Criteria for echocardiographic diagnosis do not include new, regional assessment tools which may be relevant in a phenotypically diverse disease. We adopted a systematic review and meta-analysis approach to highlight echocardiographic indices that differentiated ARVC patients and healthy controls. METHODS: Data was extracted and analysed from prospective trials that employed a case-control design meeting strict inclusion and exclusion as well as a-priori quality criteria. Structural indices included proximal RV outflow tract(RVOT1) and RV diastolic area(RVDarea). Functional indices included RV fractional area change (RVFAC), Tricuspid Annular Systolic Excursion(TAPSE), peak systolic and early diastolic myocardial velocities (S' and E' respectively) and myocardial strain. RESULTS: Patients with ARVC had larger RVOT1 (mean  SD; 34 vs. 28 mm P<0.001) and RVDarea (23 vs. 18 cm2 P<0.001) compared to healthy controls. ARVC patients also had lower RVFAC (38 vs. 46 % P<0.001), TAPSE(17 vs. 23 mm P<0.001), S' (9 vs. 12 cm.s-1 P<0.001), E' (9 vs. 13 cm.s-1 P<0.001) and myocardial strain (-17 vs. -30% P<0.001). CONCLUSION: The data from this meta-analysis support current Task Force criteria for the diagnosis of ARVC. In addition, other RV measures that reflect the complex geometry and function in ARVC clearly differentiated between ARVC and healthy controls and may provide additional diagnostic and management value. We recommend that future working groups consider this data when proposing new / revised criteria for the echocardiographic diagnosis of ARVC.

11.
J Perinatol ; 36(5): 342-6, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26796129

RESUMEN

OBJECTIVE: To determine whether a threshold of a 1-h glucose challenge test (GCT) eliminates the need for a 3-h glucose tolerance test (GTT). STUDY DESIGN: A retrospective cohort of patients undergoing GTT after GCT was ⩾140 mg dl(-1). Gestational diabetes mellitus (GDM) was diagnosed using National Diabetes Data Group (NDDG) and Carpenter-Coustan (CC) criteria. Sensitivity, specificity and predictive values were calculated for 1-h GCT values of 160 to 220 mg dl(-1). RESULT: Of 6218 patients, 988 (15.9%) had an elevated GCT and 753 (12.1%) underwent a GTT. In all, 165 (2.7%) were diagnosed with GDM using NDDG criteria, and 250 (4.0%) by CC criteria. The positive predictive value of a 1-h of GCT ⩾200 mg dl(-1) for GDM was 68.6% by NDDG and 80.0% for GDM by CC criteria. CONCLUSION: Although the predictive value of an elevated 1-h ⩽200 mg dl(-1) for GDM was high, 1 in 3 to 1 in 5 women would be overdiagnosed with GDM if the 3-h GTT was omitted.


Asunto(s)
Diabetes Gestacional/diagnóstico , Prueba de Tolerancia a la Glucosa/métodos , Adulto , Glucemia/análisis , Estudios de Cohortes , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Estados Unidos
12.
J Integr Pest Manag ; 7(1): 7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28670487

RESUMEN

The Mexican rice borer, Eoreuma loftini (Dyar), is an invasive pest of rice, Oryza sativa L., in the Gulf Coast region of the United States. This pest also damages sugarcane, Saccharum spp. hybrids; corn, Zea mays L.; and sorghum, Sorghum bicolor (L.) Moench, and feeds on weedy noncrop grasses. Multiple aspects of integrated pest management including use of pheromone traps, manipulation of planting dates, harvest cutting height, stubble management, noncrop host management, soil fertility management, host plant resistance, use of insecticides, and biological control have been studied for Mexican rice borer management. However, the current management strategy in rice primarily relies on the use of chlorantraniliprole insecticide seed treatments. This profile addresses Mexican rice borer biology and management in rice in the United States.


El barrenador mexicano del arroz [Eoreuma loftini (Dyar)] es una plaga invasora de arroz (Oryza sativa L.) en la región de la Costa del Golfo de Estados Unidos. Esta plaga también afecta híbridos de caña de azúcar (Saccharum spp.), maíz (Zea mays L.), sorgo [Sorghum bicolor (L.) Moench), y se alimenta de malezas gramíneas. Múltiples aspectos del manejo integrado de plagas incluyendo el uso de trampas con feromonas, la manipulación de las fechas de siembra, la altura del corte durante la cosecha, el manejo de rastrojos, el manejo de hospederos alternos, el manejo de la fertilidad del suelo, la resistencia de la plantas, el uso de insecticidas y el control biológico han sido estudiados para el manejo del barrenador mexicano del arroz. Sin embargo, la estrategia de actual de manejo en arroz se basa principalmente en el tratamiento químico de la semilla con el uso del insecticida clorantraniliprol. Esta revisión se enfoca en la biología y manejo del barrenador mexicano del arroz en arroz en los Estados Unidos.

13.
Environ Entomol ; 44(3): 757-66, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26313982

RESUMEN

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), is an invasive pest of sugarcane, Saccharum spp., rice, Oryza sativa L., and other graminaceous crops in the Gulf Coast region of the United States. Traps baited with E. loftini female sex pheromones were used to document establishment and distribution of E. loftini near sugarcane, rice, and noncrop hosts in seven southwest Louisiana parishes from 2009 to 2013. Additional field surveys documented larval infestations in commercial sugarcane and rice. After its initial detection in 2008, no E. loftini were detected in Louisiana in 2009 and only two adults were captured in 2010. Trapping documented range expansion into Cameron, Beauregard, and Jefferson Davis parishes in 2011 and Allen, Acadia, and Vermilion parishes in 2013. During the course of this study, E. loftini expanded its range eastward into Louisiana 120 km from the Texas border (≈22 km/yr). Surveys of larval infestations provided the first record of E. loftini attacking rice and sugarcane in Louisiana. Infestations of E. loftini in rice planted without insecticidal seed treatments in Calcasieu Parish reached damaging levels.


Asunto(s)
Distribución Animal , Mariposas Nocturnas/fisiología , Oryza , Saccharum , Animales , Control de Insectos , Especies Introducidas , Louisiana , Masculino , Mariposas Nocturnas/efectos de los fármacos , Oryza/crecimiento & desarrollo , Feromonas/farmacología , Saccharum/crecimiento & desarrollo , Atractivos Sexuales/farmacología
14.
BJOG ; 122(4): 545-51, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25515321

RESUMEN

OBJECTIVE: To investigate the risk for preterm birth associated with vaginal infections in pregnancies after a loop electrosurgical excision procedure (LEEP), compared with women with no prior LEEP. DESIGN: Multicentre retrospective cohort study. SETTING: USA. POPULATION: Women with LEEP between 1996 and 2006 were compared with two unexposed groups who had cervical biopsy or Pap test, without any other cervical procedure, in the same calendar year. METHODS: The first pregnancy progressing beyond 20 weeks of gestation in women with prior LEEP was compared with pregnancy in women without LEEP. Stratified analysis according to the presence or the absence of vaginal infection during pregnancy was used to investigate whether the risk for preterm birth differed according to the presence or the absence of infection. The interaction between LEEP and vaginal infection was investigated using multivariable logistic regression with interaction terms, as well as the Mantel-Haenszel test for homogeneity. MAIN OUTCOME MEASURES: Spontaneous preterm birth (<37 and <34 weeks of gestation). RESULTS: Of 1727 patients who met the inclusion criteria, 34.4% (n = 598) underwent LEEP prior to an index pregnancy. There was no increased risk for vaginal infections among women with LEEP compared with women without LEEP. Chlamydia infection and LEEP demonstrated significant interaction, suggesting that the presence of chlamydia infection in women with a history of LEEP augments the risk for preterm birth, compared with women with no history of LEEP. CONCLUSIONS: Vaginal infections during pregnancy in women with a history of LEEP may be associated with an increased risk for preterm birth, compared with women with no history of LEEP.


Asunto(s)
Electrocirugia/efectos adversos , Complicaciones Infecciosas del Embarazo/etiología , Complicaciones Neoplásicas del Embarazo/cirugía , Nacimiento Prematuro/etiología , Displasia del Cuello del Útero/cirugía , Neoplasias del Cuello Uterino/cirugía , Adulto , Femenino , Humanos , Recién Nacido , Prueba de Papanicolaou , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Neoplásicas del Embarazo/epidemiología , Resultado del Embarazo , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología , Displasia del Cuello del Útero/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Frotis Vaginal
15.
Bull Entomol Res ; 103(6): 656-64, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23830057

RESUMEN

The sugarcane borer, Diatraea saccharalis (F.), is a pest of graminaceous crops in the southern USA, including sugarcane, maize, and rice. This study was conducted to investigate the effect of silicon (Si) soil amendments on performance of sugarcane borer, D. saccharalis, on two rice cultivars, Cocodrie and XL723. There was a significant increase in the Si content of rice plants supplemented with calcium silicate as compared to non-treated plants. Soil Si amendment led to lower relative growth rates (RGRs) and reduced boring success of sugarcane borer larvae. Effects of soil Si amendments on borer success and RGR appeared to be more pronounced in 'Cocodrie', the cultivar relatively susceptible to borers, than in the moderately resistant cultivar, XL723. Soil Si amendment may contribute to the management of D. saccharalis through reduced feeding injury and increased exposure to adverse environmental conditions and natural enemies arising from reduced boring success.


Asunto(s)
Fertilizantes/toxicidad , Mariposas Nocturnas/efectos de los fármacos , Oryza , Silicio/toxicidad , Animales , Femenino , Herbivoria/efectos de los fármacos , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Mariposas Nocturnas/crecimiento & desarrollo , Oryza/metabolismo , Silicio/metabolismo
16.
J Econ Entomol ; 106(1): 181-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23448030

RESUMEN

Effects of treatment of rice seeds with an anthranilic diamide, chlorantraniliprole, and a neonicotinoid, thiamethoxam, on egg laying and first instar survival in rice water weevil, Lissorhoptrus oryzophilus Kuschel, were examined under greenhouse conditions. Exposure of adult weevils to rice (6-7 leaf stage) grown from seeds treated with chlorantraniliprole and thiamethoxam resulted in reduction in numbers of eggs and first instars. The low egg numbers by adults exposed to chlorantraniliprole-treated plants was confirmed as a sublethal effect on adults: adult survival was not impacted after 4 d of feeding on foliage from chlorantraniliprole-treated plants but the number of eggs laid by these weevils was reduced when released on untreated plants. Furthermore, a comparison of first instar emergence from chlorantraniliprole-treated plants and from untreated plants infested with weevils previously exposed to this chemical suggested that chlorantraniliprole was also reducing egg or first instar survival. In contrast, adults that fed on foliage from thiamethoxam-treated plants showed increased mortality. Possible sublethal effects of thiamethoxam on the number of eggs laid by adults were investigated by infesting untreated plants with weevils that survived exposure to thiamethoxam via foliar feeding (7 microg active ingredient/seed). Prior exposure to thiamethoxam through adult feeding reduced egg numbers. However, potential larvicidal or ovicidal effects of thiamethoxam seed treatments could not be detected in this study because of low first instar emergence from both thiamethoxam-treated plants and from untreated plants infested with weevils previously exposed to this chemical. These experiments revealed that the two seed treatments accomplish weevil control in different ways.


Asunto(s)
Insecticidas/toxicidad , Nitrocompuestos/toxicidad , Oviparidad/efectos de los fármacos , Oxazinas/toxicidad , Tiazoles/toxicidad , Gorgojos/efectos de los fármacos , ortoaminobenzoatos/toxicidad , Animales , Conducta Alimentaria/efectos de los fármacos , Femenino , Insecticidas/administración & dosificación , Larva , Masculino , Neonicotinoides , Nitrocompuestos/administración & dosificación , Oryza , Oxazinas/administración & dosificación , Tiametoxam , Tiazoles/administración & dosificación , ortoaminobenzoatos/administración & dosificación
17.
Placenta ; 34(1): 14-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23199792

RESUMEN

INTRODUCTION: Markers of placental dysfunction are used for risk prediction of adverse obstetric outcomes including preeclampsia and growth restriction. Although medically indicated preterm birth is often distinguished from spontaneous preterm birth, we hypothesize that similar placental dysfunction may underlay all preterm birth. We aimed to investigate whether first trimester placental protein 13 (PP-13), pregnancy associated plasma protein A (PAPP-A) and uterine artery pulsatility index, with maternal characteristics could be used to predict all preterm birth. METHODS: Prospective cohort study of singleton gestations between 11 and 14 weeks who underwent serum measurement of PP-13, PAPP-A, and measurement of uterine artery Doppler pulsatility index. Primary outcomes were preterm birth (PTB) at less than 37 and 33 weeks. Analysis performed both including and excluding preeclampsia to assess the utility of the predictors for all types of preterm birth. Predictive models assembled using logistic regression with each predictor alone and in combination, along with maternal characteristics. Predictive utility of models was assessed using receiver operating curve (ROC) analysis and sensitivities for fixed false positive values. RESULTS: Of 471 women, PTB occurred in 12.5% and early PTB (<33 weeks) occurred in 4.7%. PP-13 was decreased in PTB <37 weeks. PAPP-A was decreased in a dose-response pattern for PTB at <37 weeks and <33 weeks. Uterine artery pulsatility index was increased in early PTB. All patterns of predictors remained the same whether patients with preeclampsia were excluded or included suggesting predictive utility for all causes of PTB. Predictive models all demonstrated good predictive ability with ROC ≥ 0.90. CONCLUSIONS: PP-13, PAPP-A, and uterine artery Doppler pulsatility index obtained in the first trimester are good predictors of all types of preterm birth, both indicated and spontaneous. Models including first trimester markers combined with maternal characteristics demonstrated good predictive ability and could be investigated for application of targeted prophylactic strategies.


Asunto(s)
Biomarcadores/análisis , Análisis Químico de la Sangre , Primer Trimestre del Embarazo/sangre , Nacimiento Prematuro/sangre , Nacimiento Prematuro/diagnóstico por imagen , Ultrasonografía Prenatal , Adulto , Biomarcadores/sangre , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Embarazo , Pronóstico , Factores de Riesgo , Adulto Joven
18.
J Econ Entomol ; 102(5): 1837-45, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19886448

RESUMEN

The rice water weevil, Lissorhoptrus oryzophilus Kuschel, is the most widely distributed and destructive early season insect pest of rice, Oryza sativa L., in the United States. Economic losses result primarily from feeding by the larval stage of this insect on the roots of flooded rice plants. Prior studies suggest that infestations of rice water weevil larvae are more severe at low plant densities. Moreover, because feeding by the rice water weevil reduces rice plant tillering, a process particularly important to yield at low seeding rates, infestations by weevil larvae may have a greater impact on rice yields when rice is seeded at low rates. In total, six experiments were conducted over a 3-yr period in Louisiana and Missouri to investigate the impacts of rice seeding rate on levels of infestations by, and yield losses from, the rice water weevil. An inverse relationship between seeding rate and densities of rice water weevil larvae and pupae on a per area basis was found in two of the six experiments. Furthermore, in two of the three experiments conducted with 'Bengal' (a susceptible cultivar) in Louisiana, percentages of yield loss were significantly higher at lower seeding rates than at higher seeding rates. Overall, these results indicate that rice sown at low rates is more vulnerable to infestation by rice water weevils and more susceptible to yield losses from weevil injury. The significance of these findings in light of recent trends toward the use of lower seeding rates in drill-seeded rice is discussed.


Asunto(s)
Productos Agrícolas/economía , Productos Agrícolas/parasitología , Oryza/fisiología , Oryza/parasitología , Semillas/fisiología , Gorgojos/fisiología , Animales , Insecticidas/farmacología , Larva , Pupa , Estaciones del Año , Estados Unidos , Gorgojos/efectos de los fármacos , Gorgojos/crecimiento & desarrollo
19.
Environ Entomol ; 38(4): 1174-81, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19689897

RESUMEN

Rice, Oryza sativa, is the most important staple food for a significant portion of the world's population. Despite the importance of rice, however, induced resistance to insects has not been thoroughly studied in rice; in fact, to our knowledge, direct induced resistance after injury by chewing insects has not been shown in rice. We conducted a series of experiments designed to characterize direct induced resistance in rice after feeding by larvae of the fall armyworm (Spodoptera frugiperda J. E. Smith) and application of jasmonic acid. Weight gains and relative growth rates of fall armyworm larvae were lower when fed leaves from plants previously damaged by armyworms than when fed leaves from undamaged plants. This response was stronger at a systemic spatial scale; that is, the induced resistance was stronger in newly emerged leaves not present at the time plants were damaged than in damaged leaves themselves. Armyworm growth rates were also reduced on foliage from plants treated with jasmonic acid, a hormone known to mediate plant responses to wounding. The response to injury by armyworm larvae and to exogenous jasmonic acid was stronger in transgenic rice plants in which levels of salicylic acid (a signaling molecule that inhibits jasmonic acid) were suppressed. These results show the existence of a direct induced resistance response in rice and suggest that this response to injury by a chewing insect may be mediated by jasmonic acid.


Asunto(s)
Ciclopentanos/metabolismo , Interacciones Huésped-Parásitos , Oryza/inmunología , Oxilipinas/metabolismo , Ácido Salicílico/metabolismo , Spodoptera/fisiología , Animales , Larva/fisiología , Oryza/genética , Oryza/metabolismo , Plantas Modificadas Genéticamente/inmunología , Plantas Modificadas Genéticamente/metabolismo
20.
Cryobiology ; 59(2): 164-70, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19545558

RESUMEN

There are very few experimental reports on the comparative water transport (membrane permeability) characteristics of ejaculated and epididymal mammalian spermatozoa during freezing. In the present study, we report the effects of cooling ejaculated and epididymal bovine sperm from the same males with and without the presence of a cryoprotective agent, glycerol. Water transport data during freezing of ejaculated and epididymal bovine sperm suspensions were obtained at a cooling rate of 20 degrees C/min under two different conditions: (1) in the absence of any cryoprotective agents, CPAs and, (2) in the presence of 0.7 M glycerol. Using values published in the literature, we modeled the spermatozoa as a cylinder of length 39.8 microm and a radius of 0.4 microm with an osmotically inactive cell volume, V(b), of 0.61 V(o), where V(o) is the isotonic cell volume. The subzero water transport response is analyzed to determine the variables governing the rate of water loss during cooling of bovine spermatozoa, i.e. the membrane permeability parameters (reference membrane permeability, L(pg) and activation energy, E(Lp)). The predicted best-fit permeability parameters ranged from, L(pg)=0.021-0.038 microm/min-atm and E(Lp)=27.8-41.1 kcal/mol. The subzero water transport response and consequently the subzero water transport parameters are not significantly different between the ejaculated and epididymal bovine spermatozoa under corresponding cooling conditions. If this observation is found to be more generally valid for other mammalian species as well, then in the future the sperm extracted from the testes of a postmortem male could be optimally cryopreserved using procedures similar to those derived for ejaculated sperm.


Asunto(s)
Permeabilidad de la Membrana Celular/efectos de los fármacos , Criopreservación/veterinaria , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides/fisiología , Animales , Rastreo Diferencial de Calorimetría , Bovinos , Criopreservación/métodos , Crioprotectores/farmacología , Eyaculación , Epidídimo/citología , Epidídimo/metabolismo , Congelación , Glicerol/farmacología , Masculino , Preservación de Semen/métodos , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Agua/metabolismo
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