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1.
Front Plant Sci ; 14: 1270166, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37877090

RESUMEN

Nitrogen (N) limits crop production, yet more than half of N fertilizer inputs are lost to the environment. Developing maize hybrids with improved N use efficiency can help minimize N losses and in turn reduce adverse ecological, economical, and health consequences. This study aimed to identify single nucleotide polymorphisms (SNPs) associated with agronomic traits (plant height, grain yield, and anthesis to silking interval) under high and low N conditions. A genome-wide association study (GWAS) was conducted using 181 doubled haploid (DH) lines derived from crosses between landraces from the Germplasm Enhancement of Maize (BGEM lines) project and two inbreds, PHB47 and PHZ51. These DH lines were genotyped using 62,077 SNP markers. The same lines from the per se trials were used as parental lines for the testcross field trials. Plant height, anthesis to silking interval, and grain yield were collected from high and low N conditions in three environments for both per se and testcross trials. We used three GWAS models, namely, general linear model (GLM), mixed linear model (MLM), and Fixed and Random model Circulating Probability Unification (FarmCPU) model. We observed significant genetic variation among the DH lines and their derived testcrosses. Interestingly, some testcrosses of exotic introgression lines were superior under high and low N conditions compared to the check hybrid, PHB47/PHZ51. We detected multiple SNPs associated with agronomic traits under high and low N, some of which co-localized with gene models associated with stress response and N metabolism. The BGEM panel is, thus, a promising source of allelic diversity for genes controlling agronomic traits under different N conditions.

2.
Cell ; 186(21): 4632-4651.e23, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37776858

RESUMEN

The dynamics of immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in infants and young children by analyzing blood samples and weekly nasal swabs collected before, during, and after infection with Omicron and non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, showed no sign of decay for up to 300 days. Infants mounted a robust mucosal immune response characterized by inflammatory cytokines, interferon (IFN) α, and T helper (Th) 17 and neutrophil markers (interleukin [IL]-17, IL-8, and CXCL1). The immune response in blood was characterized by upregulation of activation markers on innate cells, no inflammatory cytokines, but several chemokines and IFNα. The latter correlated with viral load and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell multi-omics. Together, these data provide a snapshot of immunity to infection during the initial weeks and months of life.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Niño , Lactante , Humanos , Preescolar , SARS-CoV-2/metabolismo , Multiómica , Citocinas/metabolismo , Interferón-alfa , Inmunidad Mucosa
3.
medRxiv ; 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36778389

RESUMEN

The dynamics of innate and adaptive immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to SARS-CoV-2 infection in infants and young children in the first weeks and months of life by analyzing blood samples collected before, during, and after infection with Omicron and Non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, were stably maintained for >300 days. Antigen-specific memory B cell (MCB) responses were durable for 150 days but waned thereafter. Somatic hypermutation of V-genes in MCB accumulated progressively over 9 months. The innate response was characterized by upregulation of activation markers on blood innate cells, and a plasma cytokine profile distinct from that seen in adults, with no inflammatory cytokines, but an early and transient accumulation of chemokines (CXCL10, IL8, IL-18R1, CSF-1, CX3CL1), and type I IFN. The latter was strongly correlated with viral load, and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell transcriptomics. Consistent with this, single-cell ATAC-seq revealed enhanced accessibility of chromatic loci targeted by interferon regulatory factors (IRFs) and reduced accessibility of AP-1 targeted loci, as well as traces of epigenetic imprinting in monocytes, during convalescence. Together, these data provide the first snapshot of immunity to infection during the initial weeks and months of life.

4.
Clin Gastroenterol Hepatol ; 18(8): 1727-1735.e2, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31589979

RESUMEN

BACKGROUND & AIMS: The region of the esophagus 15-17 cm below the incisors, called the sub-upper esophageal sphincter (sub-UES), has not been characterized in adults with eosinophilic esophagitis (EoE) but appears different during endoscopy. We investigated how the sub-UES differs from the remaining esophagus in patients with EoE and aimed to determine whether these differences be used to distinguish patients with EoE from those with lichen planus. METHODS: We performed a prospective study of 14 patients with EoE, 7 patients with lichen planus (based on presence of Civatte bodies, dysphagia, and/or narrow esophagus with thin esophageal mucosa without signs of EoE), and 20 patients undergoing upper endoscopy for upper gastrointestinal or with dysphagia but without features of EoE (controls) at a single medical center from 2015 through 2018. Biopsies from the distal, middle, and sub-UES regions of the esophagus were analyzed by histology, quantitative PCR, and immunohistochemistry. We measured mucosal impedance (MI) in all subjects at the sub-UES and 2 cm, 5 cm, and 10 cm from the gastro-esophageal junction. RESULTS: Patients with EoE had significantly fewer eosinophils (median, 2 eosinophils/high-powered field [HPF]; range, 0-8 eosinophils/HPF) in sub-UES tissues compared with distal esophagus (median, 50 eosinophils/HPF; range, 22.5-60.8 eosinophils/HPF; P < .0001) or middle esophagus (median, 32 eosinophils/HPF; range, 19.3-60; P < .0001). Sub-UES tissues from patients with EoE had significantly less basal cell hyperplasia (P < .01), papillary elongation (P < .01), and dilated intercellular spaces (P < .01) than middle or and distal esophagus. MI in the sub-UES did not differ significantly between patients with EoE vs controls (P = .24), but was significantly lower in patients with lichen planus (median, 1344 ohms; range, 1046-1488) than patients with EoE (median, 2880 ohms; range, 2149-4858) (P < .001). mRNA and protein expression patterns did not differ significantly in the sub-UES of patients with EoE vs controls, except for expression of desmoglein-1, which was increased in sub-UES tissues from patients with EoE. CONCLUSIONS: Sub-UES tissues from patients with EoE differ in numbers of eosinophils, histologic features, and MI compared to controls or patients with lichen planus. These features might help to distinguish these 2 diseases.


Asunto(s)
Esofagitis Eosinofílica , Impedancia Eléctrica , Esofagitis Eosinofílica/diagnóstico , Eosinófilos , Mucosa Esofágica , Esfínter Esofágico Superior , Humanos , Estudios Prospectivos
5.
Plant Genome ; 12(1)2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30951103

RESUMEN

Variation in kernel composition across maize ( L.) germplasm is affected by a combination of the plant's genotype, the environment in which it is grown, and the interaction between these two elements. Adapting exotic germplasm to the US Corn Belt is highly dependent on the plant's genotype, the environment where it is grown, and the interaction between these components. Phenotypic plasticity is ill-defined when specific exotic germplasm is moved over large latitudinal distances and for the adapted variants being created. Reduced plasticity (or stability) is desired for the adapted variants, as it allows for a more rapid implementation into breeding programs throughout the Corn Belt. Here, doubled haploid lines derived from exotic maize and adapted through backcrossing exotic germplasm to elite adapted lines were used in conjunction with genome-wide association studies to explore stability in four kernel composition traits. Genotypes demonstrated a response to environments that paralleled the mean response of all genotypes used across all traits, with protein content and kernel density exhibiting the highest levels of Type II stability. Genes such as , , and were identified as potential candidates within quantitative trait locus regions. The findings within this study aid in validating previously identified genomic regions and identified novel genomic regions affecting kernel quality traits.


Asunto(s)
Zea mays/genética , Grano Comestible/genética , Calidad de los Alimentos , Genoma de Planta , Estudio de Asociación del Genoma Completo , Haploidia , Fenotipo , Fitomejoramiento
6.
Gastroenterol Hepatol (N Y) ; 14(9): 512-520, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30364386

RESUMEN

Laryngopharyngeal reflux (LPR) is an extraesophageal variant of gastroesophageal reflux disease that is associated with chronic cough, hoarseness, dysphonia, recurrent throat clearing, and globus pharyngeus. Due to nonspecific symptoms, laryngoscopy is often performed to rule out malignancy, and the diagnosis of LPR is considered with any signs of laryngeal inflammation. However, laryngoscopic findings have high interobserver variability, and, thus, most patients are tried on an empiric course of acid-suppressive therapy to see whether symptoms resolve. In this article, which focuses on the perspective and common practice of the general gastroenterologist, we review our understanding of the pathophysiology, diagnosis, and treatment of LPR based on important clinical articles in the gastroenterology literature. We also propose new diagnostic criteria for functional laryngeal disorder and review laryngeal hypersensitivity and treatment options for general gastroenterologists.

7.
Plant Genome ; 11(2)2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30025021

RESUMEN

Flowering and height related traits are extensively studied in maize for three main reasons: 1) easily obtained phenotypic measurements, 2) highly heritable, and 3) importance of these traits to adaptation and grain yield. However, variation in flowering and height traits is extensive and findings from previous studies are genotype specific. Herein, a diverse panel of exotic derived doubled haploid lines, in conjunction with genome-wide association analysis, is used to further explore adaptation related trait variation of exotic germplasm for potential use in adapting exotic germplasm to the U.S. Corn-Belt. Phenotypes for the association panel were obtained from six locations across the central-U.S. and genotyping was performed using the genotyping-by-sequencing method. Nineteen flowering time candidate genes were found for three flowering traits. Eighteen candidate genes were found for four height related traits, with the majority of the candidate genes relating to plant hormones auxin and gibberellin. A single gene was discovered for ear height that also had effects on -like flowering gene expression levels. Findings will be used to inform future research efforts of the USDA Germplasm Enhancement of Maize project and eventually aid in the rapid adaptation of exotic germplasm to temperate U.S. environments.


Asunto(s)
Flores/genética , Haploidia , Sitios de Carácter Cuantitativo , Zea mays/fisiología , Adaptación Fisiológica/genética , Estudio de Asociación del Genoma Completo , Fenotipo , Fitomejoramiento , Polimorfismo de Nucleótido Simple , Estados Unidos , Zea mays/genética
8.
Cancer Lett ; 423: 1-8, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29518480

RESUMEN

We evaluated the changes in CTC count and CTC-associated miRNAs during the course of chemotherapy in patients with metastatic colorectal cancer. Blood samples were collected from 9 metastatic colorectal cancer patients prior to chemotherapy and at every other chemotherapy session during the course of treatment. CTCs were isolated and enumerated using a size-exclusion method (CellSievo, Singapore). CTC-associated miRNAs were isolated using a paper-based, partitioning method, and analyzed using reverse transcription quantitative real-time PCR (MiRXES, Singapore). CTC count trends generally correlated with disease progression defined by radiological measurements and trends in carcinoembryonic antigen (CEA) levels; hence CTC counts may be useful in cases where CEA is not elevated. CTC-associated miRNAs identified were miR-15b, miR-16, miR-19a, miR-21, miR-25, miR-30d, miR-126, miR-185, miR-221, miR-222, and miR-324-5p. The expression of CTC-associated miRNAs did not appear to correlate with CTC count and exhibited inter-individual heterogeneity. This pilot study suggests that analysis of CTC changes during the course of treatment may be useful in monitoring response to therapy in metastatic colorectal cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , MicroARNs/genética , Células Neoplásicas Circulantes/efectos de los fármacos , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Recuento de Células , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Estudios Longitudinales , Masculino , MicroARNs/aislamiento & purificación , Persona de Mediana Edad , Metástasis de la Neoplasia , Proyectos Piloto , Estudios Prospectivos , Resultado del Tratamiento
9.
Plant Sci ; 268: 30-38, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29362081

RESUMEN

Root system architecture (RSA) is becoming recognized as important for water and nutrient acquisition in plants. This study focuses on finding single nucleotide polymorphisms (SNPs) associated with seedling RSA traits from 300 doubled haploid (DH) lines derived from crosses between Germplasm Enhancement of Maize (GEM) accessions and inbred lines PHB47 and PHZ51. These DH lines were genotyped using 62,077 SNP markers, while root and shoot phenotype data were collected from 14-day old seedlings. Genome-wide association studies (GWAS) were conducted using three models to offset false positives/negatives. Multiple SNPs associated with seedling root traits were detected, some of which were within or linked to gene models that showed expression in seedling roots. Significant trait associations involving the SNP S5_152926936 on Chromosome 5 were detected in all three models, particularly the trait network area. The SNP is within the gene model GRMZM2G021110, which is expressed in roots at seedling stage. SNPs that were significantly associated with seedling root traits, and closely linked to gene models that encode proteins associated with root development were also detected. This study shows that the GEM-DH panel may be a source of allelic diversity for genes controlling seedling root development.


Asunto(s)
Estudio de Asociación del Genoma Completo , Haploidia , Endogamia , Raíces de Plantas/anatomía & histología , Raíces de Plantas/genética , Carácter Cuantitativo Heredable , Zea mays/anatomía & histología , Zea mays/genética , Desequilibrio de Ligamiento/genética , Modelos Genéticos , Fenotipo , Brotes de la Planta/fisiología , Polimorfismo de Nucleótido Simple/genética , Análisis de Componente Principal
10.
Front Plant Sci ; 8: 1039, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28676808

RESUMEN

Brassinosteroids (BRs) and Gibberellins (GAs) are two classes of plant hormones affecting plant height (PHT). Thus, manipulation of BR and GA levels or signaling enables optimization of crop grain and biomass yields. We established backcross (BC) families, selected for increased PHT, in two elite maize inbred backgrounds. Various exotic accessions used in the germplasm enhancement in maize project served as donors. BC1-derived doubled haploid lines in the same two elite maize inbred backgrounds established without selection for plant height were included for comparison. We conducted genome-wide association studies to explore the genetic control of PHT by BR and GA. In addition, we used BR and GA inhibitors to compare the relationship between PHT, BR, and GA in inbred lines and heterozygotes from a physiological and biological perspective. A total of 73 genomic loci were discovered to be associated with PHT, with seven co-localized with GA, and two co-localized with BR candidate genes. PHT determined in field trials was significantly correlated with seedling stage BR and GA inhibitor responses. However, this observation was only true for maize heterozygotes, not for inbred lines. Path analysis results suggest that heterozygosity increases GA levels, which in turn promote BR levels. Thus, at least part of heterosis for PHT in maize can be explained by increased GA and BR levels, and seedling stage hormone inhibitor response is promising to predict heterosis for PHT.

11.
Carbohydr Polym ; 149: 282-8, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27261752

RESUMEN

The objective of this study was to understand dosage effects of the Waxy gene on the structures of amylose and amylopectin and on the properties of corn starch. Reciprocal crossing of isogenic normal and waxy corn lines was conducted to develop hybrids with different dosages (0, 1, 2, 3) of Waxy gene in the endosperm. The amylose content of starch and proportions of branch chains of DP 17-30 and extra-long branch chains (DP>100) of amylopectin were positively correlated with the Waxy-gene dosage. Proportions of short (DP<17) and long branch-chains (DP 30-80), however, were negatively correlated with the Waxy-gene dosage. The gelatinization conclusion-temperature and temperature-range of the starch were negatively correlated with the Waxy-gene dosage, indicating that amylose facilitated dissociation of the surrounding crystalline regions. These results helped us understand the function of granule-bound starch synthase I in the biosynthesis of amylose and amylopectin and impacts of Waxy-gene dosages on the properties of corn starch.


Asunto(s)
Dosificación de Gen , Proteínas de Plantas/genética , Almidón Sintasa/genética , Almidón/química , Zea mays/química , Zea mays/genética , Amilopectina/química , Amilosa/química , Lípidos/análisis , Peso Molecular , Temperatura
12.
Plant Sci ; 221-222: 69-80, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24656337

RESUMEN

The caffeic acid 3-O-methytransferase (COMT) gene is a prime candidate for cell wall digestibility improvement based on the characterization of brown midrib-3 mutants. We compared the genetic diversity and linkage disequilibrium at this locus between exotic populations sampled within the Germplasm Enhancement of Maize (GEM) project and 70 inbred lines. In total, we investigated 55 exotic COMT alleles and discovered more than 400 polymorphisms in a 2.2 kb region with pairwise nucleotide diversity (π) up to 0.017, much higher than reported π values of various genes in inbred lines. The ratio of non-synonymous to synonymous SNPs was 3:1 in exotic populations, and significantly higher than the 1:1 ratio for inbred lines. Selection tests detected selection signature in this gene in both pools, but with different evolution patterns. The linkage disequilibrium decay in exotic populations was at least four times more rapid than for inbred lines with r²>0.1 persisting only up to 100 bp. In conclusion, the alleles sampled in the GEM Project offer a valuable genetic resource to broaden genetic variation for the COMT gene, and likely other genes, in inbred background. Moreover, the low linkage disequilibrium makes this material suitable for high resolution association analyses.


Asunto(s)
Variación Genética , Desequilibrio de Ligamiento , Metiltransferasas/genética , Proteínas de Plantas/genética , Zea mays/genética , Metiltransferasas/metabolismo , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/metabolismo , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Alineación de Secuencia , Análisis de Secuencia de Proteína , Zea mays/metabolismo
13.
Insect Sci ; 21(5): 541-55, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24318539

RESUMEN

After examining ear-colonizing pest resistance, 20 maize lines from the USDA-ARS Germplasm Enhancement of Maize (GEM) Program were evaluated for whorl-feeding fall armyworm (FAW) (Spodoptera frugiperda) resistance using 4 maize inbred lines as the resistant and susceptible controls. Both FAW injury ratings at 7- and 14-d after infestation, and predator abundance and diversity at whorl stage (V6-V8) were recorded in 2009 and 2010. The survey of the diversity and abundance of predators in each experimental plot were conducted 7 d after the FAW infestation. Of the 20 germplasm lines examined, 3 of them (i.e., entries 9, 15, and 19 that were derived from tropical maize germplasm lines were originated from Uruguay, Cuba, and Thailand, respectively) were identified as the best FAW-resistant germplasm lines using the leaf injury ratings and predator survey data. In addition, the abundance and diversity of the predators were greater in 2010 than in 2009, which might have caused the low level of the FAW injury ratings on all lines examined in 2010. The 2-year data showed that the FAW injury ratings were negatively correlated to the predator abundance and diversity, which is also influence by genotype × environment interactions. The findings suggested that tropical germplasm is an important source of native resistance to the FAW and the corn earworm. At the same time, the maize genotype × environment interaction (e.g., predator attractiveness, and varying weather conditions) should be included in the multiple-year evaluations of insect and disease resistance of maize germplasm lines under field conditions.


Asunto(s)
Herbivoria , Spodoptera/fisiología , Zea mays/fisiología , Animales , Interacción Gen-Ambiente , Larva/fisiología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Spodoptera/crecimiento & desarrollo , Zea mays/genética , Zea mays/crecimiento & desarrollo
14.
J Occup Environ Hyg ; 10(9): D125-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23915295

RESUMEN

Laboratory animal procedures using gas anesthetics may amass elevated waste gas concentrations in operating rooms if controls are not implemented for capturing and removing the vapors. Area sampling using an infrared analyzer indicated isoflurane concentrations likely to exceed occupational exposure guidelines. Our study showed environmental concentrations of oxygen as high as 40% and isoflurane concentrations >100 ppm when no controls or merely passive controls were utilized. These extraneous isoflurane emissions were determined to be originating from the pre-procedural induction process as well as the gas delivery nose cone. A novel waste gas collection cylinder was designed to enclose the gas delivery nose cone and animal head during the administration of anesthetic gases. The vented cylinder utilized a house vacuum to remove the waste anesthetic gases from the surgical field. A commercially available induction chamber designed to be actively and externally exhausted was used to lower concentrations during the induction process. With implementation of local exhaust ventilation controls, waste anesthetic gas concentrations decreased to below recommended occupational exposure levels. In vitro (sham) testing compared favorably to in vivo measurements validating the reduction capability of active ventilation during rodent anesthetic administration. In vivo isoflurane reductions for the induction chamber emissions, the operating room, and the surgeon's breathing zone were 95%, 60%, and 53%, respectively. The same measurements for an in vitro procedure were 98%, 84%, and 87%, respectively.


Asunto(s)
Anestesia/veterinaria , Roedores/cirugía , Ventilación/métodos , Anestesiología/instrumentación , Animales , Monitoreo del Ambiente , Ciencia de los Animales de Laboratorio/instrumentación , National Institute for Occupational Safety and Health, U.S. , Exposición Profesional/prevención & control , Estados Unidos
15.
J Agric Food Chem ; 61(2): 379-86, 2013 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-23241103

RESUMEN

Objectives of this study were to compare ethanol production between normal and waxy corn using a cold fermentation process and to understand effects of starch structures and properties on ethanol production. Ethanol yields positively correlated (p < 0.01) with starch contents of kernels of the normal and waxy corn. The average starch-ethanol conversion efficiency of waxy corn (93.0%) was substantially greater than that of normal corn (88.2%). Waxy corn starch consisted of very little amylose and mostly amylopectin that had a shorter average branch chain length than normal corn amylopectin. Regression analyses showed that average amylopectin branch chain lengths and percentage of long branch chains (DP > 37) of waxy corn starch negatively correlated with the starch hydrolysis rate and the ethanol yield. These results indicated that starch structures and properties of the normal and waxy corn had significant effects on the ethanol yield using a cold fermentation process.


Asunto(s)
Biocombustibles/análisis , Etanol/metabolismo , Almidón/química , Amilopectina/análisis , Amilopectina/química , Fermentación , Cinética , Saccharomyces cerevisiae/metabolismo , Semillas/química , Almidón/metabolismo , Zea mays/química
16.
J Econ Entomol ; 105(4): 1457-64, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22928329

RESUMEN

Ear-colonizing insects and diseases that reduce yield and impose health threats by mycotoxin contaminations in the grain, are critical impediments for corn (Zea mays L.) production in the southern United States. Ten germplasm lines from the Germplasm Enhancement of Maize (GEM) Program in Ames, IA, and Raleigh, NC, and 10 lines (derived from GEM germplasm) from the Texas Agricultural Experiment Station in Lubbock, TX, were examined in 2007 and 2008 with local resistant and susceptible controls. Four types of insect damage and smut disease (Ustilago maydis) infection, as well as gene X environment (G X E) interaction, was assessed on corn ears under field conditions. Insect damage on corn ears was further separated as cob and kernel damage. Cob penetration rating was used to assess corn earworm [Helicoverpa zea (Boddie)] and fall armyworm [Spodoptera frugiperda (J.E. Smith)] feeding on corn cobs, whereas kernel damage was assessed using three parameters: 1) percentage of kernels discolored by stink bugs (i.e., brown stink bug [Euschistus serous (Say)], southern green stink bug [Nezara viridula (L.)], and green stink bug [Chinavia (Acrosternum) hilare (Say)]; 2) percentage of maize weevil (Sitophilus zeamais Motschulsky)-damaged kernels; and 3) percentage of kernels damaged by sap beetle (Carpophilus spp.), "chocolate milkworm" (Moodna spp.), and pink scavenger caterpillar [Pyroderces (Anatrachyntis) rileyi (Walsingham)]. The smut infection rates on ears, tassels, and nodes also were assessed. Ear protection traits (i.e., husk tightness and extension) in relation to insect damage and smut infection also were examined. Significant differences in insect damage, smut infection, and husk protection traits were detected among the germplasm lines. Three of the 20 germplasm lines were identified as being multiple insect and smut resistant. Of the three lines, entries 5 and 7 were derived from DKXL370, which was developed using corn germplasm from Brazil, whereas entry 14 was derived from CUBA117.


Asunto(s)
Resistencia a la Enfermedad/genética , Herbivoria , Interacciones Huésped-Parásitos/genética , Insectos/fisiología , Zea mays/inmunología , Animales , Zea mays/genética , Zea mays/parasitología
17.
Hum Gene Ther ; 21(4): 451-62, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19911974

RESUMEN

Toxicology studies were performed in rats and rhesus macaques to establish a safe starting dose for intratumoral injection of an oncolytic vesicular stomatitis virus expressing human interferon-beta (VSV-hIFNbeta) in patients with hepatocellular carcinoma (HCC). No adverse events were observed after administration of 7.59 x 10(9) TCID(50) (50% tissue culture infective dose) of VSV-hIFNbeta into the left lateral hepatic lobe of Harlan Sprague Dawley rats. Plasma alanine aminotransferase and alkaline phosphatase levels increased and platelet counts decreased in the virus-treated animals on days 1 and 2 but returned to pretreatment levels by day 4. VSV-hIFNbeta was also injected into normal livers or an intrahepatic McA-RH7777 HCC xenograft established in Buffalo rats. Buffalo rats were more sensitive to neurotoxic effects of VSV; the no observable adverse event level (NOAEL) of VSV-hIFNbeta in Buffalo rats was 10(7) TCID(50). Higher doses were associated with fatal neurotoxicity and infectious virus was recovered from tumor and brain. Compared with VSV-hIFNbeta, toxicity of VSV-rIFNbeta (recombinant VSV expressing rat IFN-beta) was greatly diminished in Buffalo rats (NOAEL, >10(10) TCID(50)). Two groups of two adult male rhesus macaques received 10(9) or 10(10) TCID(50) of VSV-hIFNbeta injected directly into the left hepatic lobe under computed tomographic guidance. No neurological signs were observed at any time point. No abnormalities (hematology, clinical chemistry, body weights, behavior) were seen and all macaques developed neutralizing anti-VSV antibodies. Plasma interleukin-6, tumor necrosis factor-alpha, and hIFN-beta remained below detection levels by ELISA. On the basis of these studies, we will be proposing a cautious approach to dose escalation in a phase I clinical trial among patients with HCC.


Asunto(s)
Carcinoma Hepatocelular/virología , Vectores Genéticos/administración & dosificación , Vectores Genéticos/efectos adversos , Interferón beta/metabolismo , Neoplasias Hepáticas Experimentales/virología , Hígado/virología , Virus de la Estomatitis Vesicular Indiana/fisiología , Animales , Carcinoma Hepatocelular/terapia , Chlorocebus aethiops , Vías de Administración de Medicamentos , Femenino , Humanos , Interferón beta/genética , Hígado/patología , Neoplasias Hepáticas Experimentales/terapia , Macaca mulatta , Masculino , Ratones , Ratones Endogámicos BALB C , Ratas , Ratas Sprague-Dawley , Resultado del Tratamiento , Células Vero , Virus de la Estomatitis Vesicular Indiana/genética , Virus de la Estomatitis Vesicular Indiana/metabolismo
18.
Hum Gene Ther ; 19(7): 690-8, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18576918

RESUMEN

Gliomas have a dismal prognosis, with the median survival of patients with the most common histology, glioblastoma multiforme, being only 12-15 months. Development of novel therapeutic agents is urgently needed. We have previously demonstrated that oncolytic measles virus strains derived from the Edmonston vaccine lineage have significant antitumor activity against gliomas [Phuong, L.K., Allen, C., Peng, K.W., Giannini, C., Greiner, S., Teneyck, C.J., Mishra, P.K., Macura, S.I., Russell, S.J., Galanis, E.C. (2003). Cancer. Res. 63, 2462-2469]. MV-CEA is an Edmonston vaccine lineage measles virus strain engineered to express the marker peptide carcinoembryonic antigen (CEA): CEA levels can serve as a correlate of viral gene expression. In support of a phase I clinical trial of intratumoral and resection cavity administration of MV-CEA to patients with recurrent gliomas, we assessed the neurotoxicity of MV-CEA in adult immune male rhesus macaques (Macaca mulatta). The animals ' immune status and administration schedule mimicked the trial population and proposed administration schema. Macaca mulatta represents the prototype animal species for assessment of measles neurotoxicity. The animals were stereotactically administered either vehicle (n = 1) or MV-CEA at 2 x 10(5)or 2 x 10(6) TCID(50) (each, n = 2) in the right frontal lobe in two injections on days 1 and 5. Macaques were closely monitored clinically for neurotoxicity. Body weight, temperature, complete blood count, CEA, clinical chemistries, coagulation, complement levels, immunoglobulin, measles antibody titers, viremia, and shedding (buccal swabs) were tested at multiple time points. Furthermore, cisterna magna spinal taps were performed on day 9 and 1 year after the first viral dose administration, and samples were analyzed for protein, glucose, cell differential, and presence of MV-CEA. Magnetic resonance imaging (MRI) was performed between 4 and 5 months after article administration to assess for subclinical neurotoxicity. To date, 36+ months from study initiation there has been no clinical or biochemical evidence of toxicity, including lack of neurological symptoms, fever, or other systemic symptoms and lack of immunosuppression. Quantitative RT-PCR analysis of blood, buccal swabs, and cerebrospinal fluid (CSF) was negative for MV-CEA at all time points, with the exception of viral genome deletion in the blood of one asymptomatic animal at the 2 x 10(6) TCID(50) dose level on day 85. Vero cell overlays of CSF cells and supernatant were negative for viral recovery. There was no detection of CEA in serum or CSF at any time point. MRI scans were negative for imaging abnormalities and showed no evidence of encephalitis. Our results support the safety of CNS administration of MV-CEA in glioma patients. A clinical trial of intratumoral and resection cavity administration of MV-CEA in patients with recurrent glioblastoma multiforme is currently ongoing.


Asunto(s)
Neoplasias Encefálicas/terapia , Vacunas contra el Cáncer , Antígeno Carcinoembrionario/metabolismo , Vectores Genéticos , Glioma/terapia , Virus del Sarampión , Animales , Encéfalo/virología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/prevención & control , Vacunas contra el Cáncer/administración & dosificación , Vacunas contra el Cáncer/efectos adversos , Vacunas contra el Cáncer/genética , Antígeno Carcinoembrionario/genética , Chlorocebus aethiops , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Efecto Citopatogénico Viral , Vías de Administración de Medicamentos , Vectores Genéticos/administración & dosificación , Vectores Genéticos/efectos adversos , Glioma/genética , Glioma/patología , Glioma/prevención & control , Humanos , Macaca mulatta , Masculino , Virus del Sarampión/genética , Virus del Sarampión/patogenicidad , Recurrencia , Resultado del Tratamiento , Células Vero
19.
Mol Ther ; 12(5): 835-41, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16054438

RESUMEN

The sodium-iodide symporter (NIS) is primarily a thyroid protein, providing for the accumulation of iodide for biosynthesis of thyroid hormones. Native NIS expression has made possible the use of radioactive iodide to image and treat thyroid disease successfully. The current study, using adult male beagle dogs, was carried out in preparation for a Phase I clinical trial of adenovirus-mediated NIS gene (approved symbol SLC5A5) therapy for prostate cancer. Direct intraprostatic injection of virus (Ad5/CMV/NS) was followed by iv injection of 3 mCi 123I and serial image acquisition. The dogs were then given a therapeutic dose of 131I (116 mCi/m2) and observed for 7 days. SPECT/CT fusion imaging revealed clear images of the NIS-transduced prostates. Dosimetry calculations revealed an average absorbed dose to the prostate of 23 +/- 42 cGy/mCi 131I, with acceptably low radiation doses to other organs. This study demonstrated the successful introduction of localized NIS expression in the prostate gland of dogs, with no vector-related toxicity observed. None of the animals experienced any surgical complications, and serum chemistry panels showed no significant change following therapy. The results presented provide further evidence of the safety and efficacy of NIS as a therapeutic gene and support translation of this work into the clinical setting.


Asunto(s)
Adenoviridae/genética , Terapia Genética , Neoplasias de la Próstata/terapia , Simportadores/uso terapéutico , Animales , Modelos Animales de Enfermedad , Perros , Radioisótopos de Yodo/uso terapéutico , Masculino , Neoplasias de la Próstata/diagnóstico por imagen , Radiometría , Cintigrafía , Radiofármacos/uso terapéutico , Simportadores/genética , Transducción Genética , Transfección
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