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1.
Pest Manag Sci ; 80(1): 149-155, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37139834

RESUMEN

Witchweed (Striga hermonthica), also called striga, is a parasitic weed that causes high yield losses in maize on more than 200 000 ha in Kenya alone. A new commercial, biological herbicide developed in Kenya is able to control striga effectively. The product was approved for use by the Pest Control Products Board in Kenya in September, 2021. It is self-produced in villages using a secondary inoculum provided by a commercial company. The formulated product has some disadvantages, which are a complicated production process, a very short shelf life and high application rate. Additionally, the product has to be applied manually and therefore can only be used in manual production, leaving out the opportunity for farmers using mechanization. For this reason, efforts have been made to formulate the active ingredient Fusarium oxysporum f. sp. strigae strain DSM 33471, as a powder and to use it as a seed coating agent. This article deals with the production of the Fusarium spore powder, its properties, its application to the seed, and its herbicidal effect demonstrated in the first two field trials. The F. oxysporum strain was originally isolated from a wilting striga plant in Kenya. The strain was virulence enhanced to over produce the amino acids leucine, methionine and tyrosine. These amino acids are responsible for a second mode of action apart from the wilting causing effect of the fungus on striga. Whereas leucine and tyrosine have a herbicidal effect, ethylene from methionine triggers the germination of striga seeds in the soil. Additionally, the strain has been improved to be resistant to the fungicide captan, which is commonly used to treat maize seed in Kenya. Seed coating tests conducted on 25 striga-infested small holder farms spread out in six counties of western Kenya reported yield increases of up to 88%. A second trial carried out by the Kenyan Agricultural and Livestock Research Organization showed a 93% reduction of emerged striga plants. © 2023 Society of Chemical Industry.


Asunto(s)
Striga , Kenia , Leucina , Polvos/farmacología , Semillas , Tirosina/farmacología , Metionina
2.
Pest Manag Sci ; 80(1): 65-71, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37682845

RESUMEN

The high-level view of global food systems identifies three all-encompassing barriers to the adoption of food systems solutions: knowledge, policy, and finance. These barriers, and the siloed characteristics of each of these, have hindered the development and adoption of microbial herbicides. How knowledge, policy, and finance are related to the Toothpick Project's path of commercializing a new bioherbicide, early in the scope of the industry, is discussed here. The Toothpick Project's innovation, developed over four decades and commercialized in 2021, uses strains of Fusarium oxysporum f.sp. strigae selected for overproduction and excretion of specific amino acids, killing the parasitic weed Striga hermonthica (Striga or witchweed), Africa's worst pest threat to food security. Historically, bioherbicides have not been a sufficient alternative to the dominant use of synthetic chemical herbicides. To be used safely as bioherbicides, plant pathogens need to be host specific, non-toxic, and yet sufficiently virulent to control a specific weed. For commercialization, bioherbicides must be affordable and require a sufficient shelf life for distribution. Given the current triple storm encountered by the chemical herbicide industry (herbicide-resistant weeds, lawsuits, and consumer pushback), there exists an opportunity to use certain plant pathogens as bioherbicides by enhancing their virulence. By discussing barriers in the scope of knowledge, policy, and finance in the development of the Toothpick Project's new microbial bioherbicide, we hope to help others to anticipate the challenges and provide change-leaders, particularly in policy and finance, a ground level perspective of bioherbicide development. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Herbicidas , Striga , Kenia , Virulencia , Malezas , Herbicidas/farmacología
3.
PLoS One ; 18(5): e0255764, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37216356

RESUMEN

Potatoes are a dietary staple consumed by a significant portion of the world, providing valuable carbohydrates and vitamins. However, most commercially produced potatoes have a high content of highly branched amylopectin starch, which generally results in a high glycemic index (GI). Consumption of foods with high levels of amylopectin elicit a rapid spike in blood glucose levels, which is undesirable for individuals who are pre-diabetic, diabetic, or obese. Some cultivars of potatoes with lower amylopectin levels have previously been identified and are commercially available in niche markets in some countries, but they are relatively unavailable in the United States and Latin America. The high glycemic index of widely available potatoes presents a problematic "consumer's dilemma" for individuals and families that may not be able to afford a better-balanced, more favorable diet. Some native communities in the Andes (Bolivia, Chile, and Peru) reportedly embrace a tradition of providing low glycemic tubers to people with obesity or diabetes to help people mitigate what is now understood as the negative effects of high blood sugar and obesity. These cultivars are not widely available on a global market. This study examines 60 potato cultivars to identify potatoes with low amylopectin. Three independent analyses of potato starch were used: microscopic examination of granule structure, water absorption, and spectrophotometric analysis of iodine complexes to identify potato cultivars with low amylopectin Differences among cultivars tested were detected by all three types of analyses. The most promising cultivars are Huckleberry Gold, Muru, Multa, Green Mountain, and an October Blue x Colorado Rose cross. Further work is necessary to document the ability of these low amylopectin cultivars to reduce blood glucose spike levels in human subjects.


Asunto(s)
Solanum tuberosum , Almidón , Humanos , Almidón/química , Amilopectina/química , Solanum tuberosum/química , Glucemia , Obesidad
4.
Urol Pract ; 9(4): 294-305, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37145778

RESUMEN

INTRODUCTION: Same-day discharge (SDD) following robot-assisted radical prostatectomy (RARP) is emerging as the standard of care. We conducted a systematic review and meta-analysis to evaluate the differences in perioperative characteristics, complication/readmissions rates and satisfaction/cost data between inpatient (IP) RARP and SDD RARP. METHODS: This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was prospectively registered with PROSPERO (CRD42021258848). A comprehensive search of PubMed®, Embase®, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov and conference abstract publications was performed. A leave-one-out sensitivity analysis was performed to control for heterogeneity and risk of bias. RESULTS: A total of 14 studies were included with a pooled population of 3,795 patients, including 2,348 (61.9%) IP RARPs and 1,447 (38.1%) SDD RARPs. SDD pathways varied, though many commonalities were present in patient selection, perioperative recommendations and postoperative management. When compared to IP RARP, SDD RARP had no differences in ≥grade 3 Clavien-Dindo complications (RR: 0.4, 95% CI 0.2, 1.1, p=0.07), 90-day readmission rates (RR: 0.6, 95% CI 0.3, 1.1, p=0.10) or unscheduled emergency department visits (RR: 1.0, 95% CI 0.3, 3.1, p=0.97). Cost savings per patient ranged between $367 and $2,109, and overall satisfaction was high at 87.5%-100%. CONCLUSIONS: SDD following RARP is both feasible and safe, while potentially offering health care cost savings with high patient satisfaction rates. Data from this study will inform the uptake and development of future SDD pathways in contemporary urological care such that it may be offered to a broader patient population.

5.
Urol Pract ; 9(4): 304-305, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37145792
6.
Entropy (Basel) ; 23(7)2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34202081

RESUMEN

The Carnot cycle and the attendant notions of reversibility and entropy are examined. It is shown how the modern view of these concepts still corresponds to the ideas Clausius laid down in the nineteenth century. As such, they reflect the outmoded idea, current at the time, that heat is motion. It is shown how this view of heat led Clausius to develop the entropy of a body based on the work that could be performed in a reversible process rather than the work that is actually performed in an irreversible process. In consequence, Clausius built into entropy a conflict with energy conservation, which is concerned with actual changes in energy. In this paper, reversibility and irreversibility are investigated by means of a macroscopic formulation of internal mechanisms of damping based on rate equations for the distribution of energy within a gas. It is shown that work processes involving a step change in external pressure, however small, are intrinsically irreversible. However, under idealised conditions of zero damping the gas inside a piston expands and traces out a trajectory through the space of equilibrium states. Therefore, the entropy change due to heat flow from the reservoir matches the entropy change of the equilibrium states. This trajectory can be traced out in reverse as the piston reverses direction, but if the external conditions are adjusted appropriately, the gas can be made to trace out a Carnot cycle in P-V space. The cycle is dynamic as opposed to quasi-static as the piston has kinetic energy equal in difference to the work performed internally and externally.

7.
J Urol ; 206(2): 346-353, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33818139

RESUMEN

PURPOSE: Oncologic, urinary, and sexual outcomes are important to patients receiving prostate cancer surgery. The objective of this study was to determine if providing surgical report cards (SuReps) to surgeons resulted in improved patient outcomes. MATERIALS AND METHODS: A prospective before-and-after study was conducted at The Ottawa Hospital. A total of 422 consecutive patients undergoing radical prostatectomy were enrolled. The intervention was provision of report cards to surgeons. The control cohort was patients treated before report card feedback (pre-SuRep), and the intervention cohort was patients treated after report card feedback (post-SuRep). The primary outcomes were postoperative erectile function, urinary continence, and positive surgical margins. RESULTS: Baseline characteristics were similar between groups. Almost all patients (99%) were continent and the majority (59%) were potent prior to surgery. Complete 1-year followup was available for 400 patients (95%). Nerve sparing surgery increased from 70% pre-SuRep to 82% post-SuRep (p=0.01). There was a nonstatistically significant increase in the proportion of patients with a positive surgical margin post-SuRep (31% pre-SuRep vs 39% post-SuRep, p=0.08). There was no difference in postoperative erectile function (17% vs 18%, p=0.7) and a decrease in continence (75% vs 65%, p=0.02) at 1 year postoperatively. CONCLUSIONS: The SuRep platform allows accurate reporting of surgical outcomes that can be used for patient counseling. However, the provision of surgical report cards did not improve functional or oncologic outcomes. Longer durations of feedback, report card modifications, or targeted interventions are likely necessary to improve outcomes.


Asunto(s)
Competencia Clínica , Retroalimentación , Prostatectomía/normas , Mejoramiento de la Calidad , Cirujanos , Auditoría Clínica , Estudios Controlados Antes y Después , Disfunción Eréctil/prevención & control , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Ontario , Complicaciones Posoperatorias , Estudios Prospectivos , Neoplasias de la Próstata/cirugía , Calidad de Vida , Incontinencia Urinaria/prevención & control
8.
Can J Ophthalmol ; 53(4): 349-353, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30119788

RESUMEN

OBJECTIVE: To assess corticosteroid-sparing and inflammation control in patients with noninfectious scleritis treated with methotrexate. DESIGN: Retrospective review. PARTICIPANTS: Patients who received methotrexate treatment for noninfectious scleritis and who had 12 months of follow-up after treatment initiation were included in this review. METHODS: The clinical records of noninfectious scleritis patients presenting at the University of Ottawa Eye Institute between September 1, 2010 and December 31, 2014 treated with methotrexate were retrospectively reviewed. Seventeen patients (21 eyes) were included in the study. Main outcome included inflammation control and corticosteroid-sparing success. Secondary outcomes were reduction of immunosuppression load and best-corrected visual acuity. RESULTS: The proportion of eyes with corticosteroid-sparing success was 69.2% at 3 months and 92.3% at 12 months. The proportion of eyes that achieved inflammation control was 61.9% at 3 months and 90.5% at 12 months. The corticosteroid immunosuppression load at treatment start was 1.9 ± 2.07 and at 12 months was 0.48 ± 1.03 (p < 0.01). There was no statistically significant difference in best-corrected visual acuity. CONCLUSIONS: The treatment of noninfectious scleritis with methotrexate appears to be effective at both achieving steroid-sparing success and controlling inflammation during 12 months of therapy. Immunosuppression load decreased significantly over 12 months of therapy while best corrected visual acuity was stable.


Asunto(s)
Metotrexato/administración & dosificación , Esclerótica/patología , Escleritis/tratamiento farmacológico , Agudeza Visual , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Inmunosupresores/administración & dosificación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Escleritis/diagnóstico , Resultado del Tratamiento
9.
J Immigr Minor Health ; 20(4): 763-765, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28735454

RESUMEN

The number of Internally Displaced People is growing globally with a significant number travelling to countries such as Canada. These individuals have unique health care needs that are significantly impacted by several social determinants of health, which provides a challenge to the physician as they must address the biological, psychological and social factors in order to effectively improve the health of this population. The physician must work at the individual, national, and international levels and collaborate with other health care workers in order to effectively address these complex health care issues. Some recent strategies that show promise in targeting these complex care issues include knowledge sharing among medical professionals, specialized treatment approaches including treatment through telemedicine as well as political advocacy. The application of strategies such as these, along with increased awareness and commitment from physicians, will work to improve health care and prevent negative health outcomes in this growing population.


Asunto(s)
Atención a la Salud/organización & administración , Emigrantes e Inmigrantes , Estado de Salud , Salud Mental/etnología , Rol del Médico , Canadá , Conducta Cooperativa , Humanos , Difusión de la Información , Política , Salud Poblacional , Trauma Psicológico/etnología , Determinantes Sociales de la Salud/etnología , Estrés Psicológico/etnología , Telemedicina/organización & administración , Poblaciones Vulnerables/etnología
10.
Front Plant Sci ; 8: 842, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28588599

RESUMEN

Certain amino acids induce inhibitory effects in plant growth due to feedback inhibition of metabolic pathways. The inhibition patterns depend on plant species and the plant developmental stage. Those amino acids with inhibitory action on specific weeds could be utilized as herbicides, however, their use for weed control has not been put into practice. Orobanche minor is a weed that parasitizes red clover. O. minor germination is stimulated by clover root exudates. The subsequent seedling is an obligated parasite that must attach quickly to the clover root to withdraw its nutrients. Early development of O. minor is vulnerable to amino acid inhibition and therefore, a series of in vitro, rhizotron, and field experiments were conducted to investigate the potential of amino acids to inhibit O. minor parasitism. In in vitro experiments it was found that among a collection of 20 protein amino acids, lysine, methionine and tryptophan strongly interfere with O. minor early development. Field research confirmed their inhibitory effect but revealed that methionine was more effective than lysine and tryptophan, and that two successive methionine applications at 308 and 543 growing degree days inhibited O. minor emergence in red clover up to 67%. We investigated additional effects with potential to influence the practical use of amino acids against broomrape weeds, whether the herbicidal effect may be reversible by other amino acids exuded by host plants or may be amplified by inducing host resistance barriers against O. minor penetration. This paper suggests that amino acids may have the potential to be integrated into biorational programs of broomrape management.

11.
HSS J ; 13(1): 2-6, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28167866

RESUMEN

BACKGROUND: The current role of metal-on-metal (MoM) bearings in hip arthroplasty remains controversial. The low wear offered by MoM bearings compared to metal-on-polyethylene and the possibility of a lower risk of dislocation with larger head sizes, encouraged a trend towards the re-introduction of the MoM bearing couple. However, recent evidence has shown that not all designs of the MoM bearing have been successful. QUESTIONS/PURPOSES: The purpose of this paper is to provide an update on the use of MoM bearings and address the following issues: (1) the reintroduction of metal-on-metal bearings in total hip arthroplasty, (2) the failure of metal-on-metal bearings in stemmed total hip arthroplasty, (3) the role of metal-on-metal hip resurfacing in modern orthopaedics and (4) metal-on-metal hip resurfacing versus total hip arthroplasty. METHODS: A literature search strategy was conducted using various search terms in MEDLINE and Embase. The highest quality articles that met the inclusion criteria and best answered the topics of focus of this review were selected. Key search terms included 'metal-on-metal', 'total hip arthroplasty' and 'hip resurfacing'. RESULTS: The initial search retrieved 1240 articles. Twenty-two articles were selected and used in the review. CONCLUSION: Metal-on-metal hip resurfacing is still a suitable treatment option in specific patient populations with the appropriate implant design and surgical skill, while stemmed metal-on-metal total hip arthroplasty should be avoided in all patient populations. Continued follow-up of patients undergoing metal-on-metal hip resurfacing is critical in order to further understand the long-term outcomes of these patients and why certain complications tend to occur with this procedure.

12.
Front Plant Sci ; 7: 1121, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27551284

RESUMEN

Striga hermonthica (witchweed) is a parasitic weed that attacks and significantly reduces the yields of maize, sorghum, millet, and sugarcane throughout sub-Saharan Africa. Low cost management methods such as hand weeding, short crop rotations, trap cropping, or conventional biocontrol have not been effective. Likewise, Striga-tolerant or herbicide-resistant maize cultivars are higher yielding, but are often beyond the economic means of sustenance farmers. The fungal pathogen, Fusarium oxysporum f.sp. strigae, has been the object of numerous studies to develop Striga biocontrol. Under experimental conditions this pathogen can reduce the incidence of Striga infestation but field use is not extensive, perhaps because it has not been sufficiently effective in restoring crop yield and reducing the soil Striga seed bank. Here we brought together Kenyan and US crop scientists with smallholder farmers to develop and validate an effective biocontrol strategy for management of Striga on smallholder farms. Key components of this research project were the following: (1) Development of a two-step method of fungal delivery, including laboratory coating of primary inoculum on toothpicks, followed by on-farm production of secondary field inoculum in boiled rice enabling delivery of vigorous, fresh inoculum directly to the seedbed; (2) Training of smallholder farmers (85% women), to produce the biocontrol agent and incorporate it into their maize plantings in Striga-infested soils and collect agronomic data. The field tests expanded from 30 smallholder farmers to a two-season, 500-farmer plot trial including paired plus and minus biocontrol plots with fertilizer and hybrid seed in both plots and; (3) Concerted selection of variants of the pathogen identified for enhanced virulence, as has been demonstrated in other host parasite systems were employed here on Striga via pathogen excretion of the amino acids L-leucine and L-tyrosine that are toxic to Striga but innocuous to maize. This overall strategy resulted in an average of >50% increased maize yield in the March to June rains season and >40% in the September to December rains season. Integration of this enhanced plant pathogen to Striga management in maize can significantly increase the maize yield of smallholder farmers in Kenya.

13.
PLoS One ; 9(9): e105547, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25184292

RESUMEN

The Pseudomonas syringae complex is composed of numerous genetic lineages of strains from both agricultural and environmental habitats including habitats closely linked to the water cycle. The new insights from the discovery of this bacterial species in habitats outside of agricultural contexts per se have led to the revelation of a wide diversity of strains in this complex beyond what was known from agricultural contexts. Here, through Multi Locus Sequence Typing (MLST) of 216 strains, we identified 23 clades within 13 phylogroups among which the seven previously described P. syringae phylogroups were included. The phylogeny of the core genome of 29 strains representing nine phylogroups was similar to the phylogeny obtained with MLST thereby confirming the robustness of MLST-phylogroups. We show that phenotypic traits rarely provide a satisfactory means for classification of strains even if some combinations are highly probable in some phylogroups. We demonstrate that the citrate synthase (cts) housekeeping gene can accurately predict the phylogenetic affiliation for more than 97% of strains tested. We propose a list of cts sequences to be used as a simple tool for quickly and precisely classifying new strains. Finally, our analysis leads to predictions about the diversity of P. syringae that is yet to be discovered. We present here an expandable framework mainly based on cts genetic analysis into which more diversity can be integrated.


Asunto(s)
Citrato (si)-Sintasa/genética , Genes Bacterianos , Genoma Bacteriano , Filogenia , Pseudomonas syringae , Secuencia de Bases , Bases de Datos Genéticas , Ecosistema , Genes Esenciales , Variación Genética , Genotipo , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Fenotipo , Pseudomonas syringae/clasificación , Pseudomonas syringae/genética
14.
Environ Microbiol ; 16(7): 2301-15, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24612372

RESUMEN

As a species complex, Pseudomonas syringae exists in both agriculture and natural aquatic habitats. P.viridiflava, a member of this complex, has been reported to be phenotypically largely homogenous. We characterized strains from different habitats, selected based on their genetic similarity to previously described P.viridiflava strains. We revealed two distinct phylogroups and two different kinds of variability in phenotypic traits and genomic content. The strains exhibited phase variation in phenotypes including pathogenicity and soft rot on potato. We showed that the presence of two configurations of the Type III Secretion System [single (S-PAI) and tripartite (T-PAI) pathogenicity islands] are not correlated with pathogenicity or with the capacity to induce soft rot in contrast to previous reports. The presence/absence of the avrE effector gene was the only trait we found to be correlated with pathogenicity of P.viridiflava. Other Type III secretion effector genes were not correlated with pathogenicity. A genomic region resembling an exchangeable effector locus (EEL) was found in S-PAI strains, and a probable recombination between the two PAIs is described. The ensemble of the variability observed in these phylogroups of P.syringae likely contributes to their adaptability to alternating opportunities for pathogenicity or saprophytic survival.


Asunto(s)
Regulación Bacteriana de la Expresión Génica , Variación Genética , Genoma Bacteriano , Pseudomonas syringae/patogenicidad , Pseudomonas/patogenicidad , Solanum tuberosum/microbiología , Adaptación Biológica , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sistemas de Secreción Bacterianos/genética , Sitios Genéticos , Islas Genómicas , Genotipo , Fenotipo , Filogenia , Enfermedades de las Plantas/microbiología , Pseudomonas/clasificación , Pseudomonas/genética , Pseudomonas/metabolismo , Pseudomonas syringae/genética , Pseudomonas syringae/metabolismo , Virulencia
15.
Glob Chang Biol ; 20(2): 341-51, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24399753

RESUMEN

Landscapes influence precipitation via the water vapor and energy fluxes they generate. Biologically active landscapes also generate aerosols containing microorganisms, some being capable of catalyzing ice formation and crystal growth in clouds at temperatures near 0 °C. The resulting precipitation is beneficial for the growth of plants and microorganisms. Mounting evidence from observations and numerical simulations support the plausibility of a bioprecipitation feedback cycle involving vegetated landscapes and the microorganisms they host. Furthermore, the evolutionary history of ice nucleation-active bacteria such as Pseudomonas syringae supports that they have been part of this process on geological time scales since the emergence of land plants. Elucidation of bioprecipitation feedbacks involving landscapes and their microflora could contribute to appraising the impact that modified landscapes have on regional weather and biodiversity, and to avoiding inadvertent, negative consequences of landscape management.


Asunto(s)
Bacterias/metabolismo , Planeta Tierra , Ecosistema , Hielo , Lluvia , Atmósfera , Bacterias/clasificación
16.
Genome Announc ; 2(1)2014 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-24459267

RESUMEN

Here, we report the draft genome sequences for 7 phylogenetically diverse isolates of Pseudomonas syringae, obtained from numerous environmental sources and geographically proximate crop species. Overall, these sequences provide a wealth of information about the differences (or lack thereof) between isolates from disease outbreaks and those from other sources.

17.
J Diabetes ; 2(1): 28-35, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20923472

RESUMEN

BACKGROUND: Energy intake from snacks has been increasing in the American diet, but insulin and glucose responses to foods are generally reported for meal-sized portions (800-1200 kJ). Established methods for insulin determination routinely use indwelling catheters and radioimmunoassay (RIA). The aim of the present study was to develop a more facile method, collecting fingerstick blood samples and measuring insulin with precise ELISA, and then applying this method to determine responses to snack-sized food portions. METHODS: Six healthy, fasting adult volunteers consumed seven different snack foods on separate days, containing approximately 400 kJ/portion. Insulin was measured by ELISA and glucose was measured with the hexokinase procedure in samples collected by fingerstick at 0, 30, and 60 min after consumption of the snack food. RESULTS: A portion of doughnut (half a glazed doughnut) led to marked changes in insulin and glucose; skim milk, an apple, and oatmeal changed insulin significantly; wrinkled peas resulted in a lower glucose response than smooth peas; and walnuts led to non-significant changes in both insulin and glucose over a 60-min period. CONCLUSIONS: The fingerstick sampling and insulin measurement procedure is simple, economical, and more precise than established RIA. The method can be applied to children and adults to monitor insulin responses following food consumption, as well as during therapeutic assessments or intervention trials. Public health advisories regarding snacks that minimize increases in insulin are desirable for individuals trying to reduce or maintain their weight, because elevated insulin stimulates carbohydrate conversion to fat and suppresses the mobilization of stored triglycerides for energy generation.


Asunto(s)
Glucemia/análisis , Ingestión de Alimentos/fisiología , Dedos/irrigación sanguínea , Insulina/sangre , Agujas , Periodo Posprandial/fisiología , Adulto , Capilares , Niño , Ensayo de Inmunoadsorción Enzimática/métodos , Índice Glucémico , Humanos
19.
Pest Manag Sci ; 65(5): 581-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19288472

RESUMEN

A considerable number of plant pathogens have been studied for their possible use in weed control. Some have proven virulent enough to control weed species and to compete commercially with chemical herbicides. However, most pathogens of weeds are not useful in their wild form because they are not sufficiently host-specific and/or virulent. The authors believe that these barriers can be overcome. The present research has focused on the inhibitory effects of certain amino acids on the growth and development of specific plants. Pathogens that overproduce these selected amino acids can be easily selected from a pool of spontaneous mutants. Such mutants can have increased pathogenicity to their target weed and enhanced field performance as biocontrol agents. Enhancement of biocontrol efficacy in three separate pathogen-host systems, two with Fusarium and one with Pseudomonas, has already been reported. It is proposed to use the same technology to enhance the biocontrol efficacy of the two species of Fusarium that are host-specific pathogens of the broomrape group of parasitic weeds. The stepwise approach outlined can lead to obtaining enhanced biocontrol agents capable of producing inhibitory levels of selected amino acids in situ. It is proposed that these approaches, in combination with other methods of virulence enhancement, will lead to sustainable systems of biological control of parasitic weeds.


Asunto(s)
Fusarium/patogenicidad , Técnicas Genéticas , Técnicas Microbiológicas , Orobanche/microbiología , Enfermedades de las Plantas/microbiología , Pseudomonas/patogenicidad , Aminoácidos/metabolismo , Aminoácidos/farmacología , Fusarium/metabolismo , Interacciones Huésped-Patógeno , Orobanche/efectos de los fármacos , Orobanche/metabolismo , Control Biológico de Vectores , Pseudomonas/metabolismo , Virulencia
20.
Plant Sci ; 177(5): 377-89, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20467463

RESUMEN

High-yielding cereals and other staples have produced adequate calories to ward off starvation for much of the world over several decades. However, deficiencies in certain amino acids, minerals, vitamins and fatty acids in staple crops, and animal diets derived from them, have aggravated the problem of malnutrition and the increasing incidence of certain chronic diseases in nominally well-nourished people (the so-called diseases of civilization). Enhanced global nutrition has great potential to reduce acute and chronic disease, the need for health care, the cost of health care, and to increase educational attainment, economic productivity and the quality of life. However, nutrition is currently not an important driver of most plant breeding efforts, and there are only a few well-known efforts to breed crops that are adapted to the needs of optimal human nutrition. Technological tools are available to greatly enhance the nutritional value of our staple crops. However, enhanced nutrition in major crops might only be achieved if nutritional traits are introduced in tandem with important agronomic yield drivers, such as resistance to emerging pests or diseases, to drought and salinity, to herbicides, parasitic plants, frost or heat. In this way we might circumvent a natural tendency for high yield and low production cost to effectively select against the best human nutrition. Here we discuss the need and means for agriculture, food processing, food transport, sociology, nutrition and medicine to be integrated into new approaches to food production with optimal human nutrition as a principle goal.


Asunto(s)
Agricultura , Productos Agrícolas/genética , Trastornos Nutricionales/prevención & control , Plantas Comestibles/genética , Biotecnología , Cruzamiento , Productos Agrícolas/química , Productos Agrícolas/normas , Abastecimiento de Alimentos , Tecnología de Alimentos , Alimentos Fortificados , Humanos , Valor Nutritivo , Plantas Comestibles/química
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