RESUMEN
OBJECTIVE: To understand the impact of Na reduction on the nutrient content of Child and Adult Care Food Program (CACFP) meals served through At-Risk Afterschool Meals (ARASM) without compromising the nutritional quality of the meals served. DESIGN: Sodium Reduction in Communities Program (SRCP) partnered with a CACFP ARASM programme from October 2016 to September 2021. We assessed changes in Healthy Eating Index 2015 (HEI-2015) food component scores and macro- and micronutrients using cross-sectional nutrient analyses of October 2016 and 2020 menus. SETTING: ARASM programme sites in Indianapolis, IN, USA. PARTICIPANTS: October 2016 and 2020 menus from one CACFP ARASM programme. INTERVENTION: Na reduction strategies included implementing food service guidelines, modifying meal components, changing procurement practices and facilitating environmental changes to promote lower Na items. RESULTS: From baseline in 2016 to 2020, fifteen meal components were impacted by the intervention, which impacted 17 (85 %) meals included in the analysis. Average Na per meal reduced significantly between 2016 (837·9 mg) and 2020 (627·9 mg) (P = 0·002). Between 2016 and 2020, there were significant increases in whole grains (P = 0·003) and total vegetables (P < 0·001) and significant reductions in refined grains (P = 0·001) and Na (P = 0·02), all per 1000 kcal served. CONCLUSIONS: This study demonstrates that Na content can be reduced in CACFP meals without compromising the nutritional quality of meals served. Future studies are needed to identify feasible best practices and policies to reduce Na content in the CACFP meal pattern.
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Servicios de Alimentación , Comidas , Humanos , Niño , Adulto , Estudios Transversales , Verduras , Nutrientes , Sodio , Cuidado del Niño , Política NutricionalRESUMEN
To improve the nitrogen fixation, legume crops are often inoculated with selected effective rhizobia. However, there is large variation in how well the inoculant strains compete with the indigenous microflora in soil. To assess the success of the inoculant, it is necessary to distinguish it from other, closely related strains. Methods used until now have generally been based either on fingerprinting methods or on the use of reporter genes. Nevertheless, these methods have their shortcomings, either because they do not provide sufficiently specific information on the identity of the inoculant strain, or because they use genetically modified organisms that need prior authorization to be applied in the field or other uncontained environments. Another possibility is to target a gene that is naturally present in the bacterial genomes. Here we have developed a method that is based on amplicon sequencing of the bacterial housekeeping gene rpoB, encoding the beta-subunit of the RNA polymerase, which has been proposed as an alternative to the 16S rRNA gene to study the diversity of rhizobial populations in soils. We evaluated the method under laboratory and field conditions. Peanut seeds were inoculated with various Bradyrhizobium strains. After nodule development, DNA was extracted from selected nodules and the nodulating rhizobia were analysed by amplicon sequencing of the rpoB gene. The analyses of the sequence data showed that the method reliably identified bradyrhizobial strains in nodules, at least at the species level, and could be used to assess the competitiveness of the inoculant compared to other bradyrhizobia.
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Bradyrhizobium , Fabaceae , Rhizobium , Arachis , Bradyrhizobium/genética , ADN Bacteriano/genética , Filogenia , ARN Ribosómico 16S/genética , Rhizobium/genética , Nódulos de las Raíces de las Plantas , SimbiosisRESUMEN
PURPOSE AND OBJECTIVES: Through the Centers for Disease Control and Prevention's Sodium Reduction in Communities Program, the Marion County Public Health Department and partners implemented sodium reduction strategies in distributive meal programs (ie, low- or no-cost meals available to under-resourced populations) to meet the long-term goal of reducing the burden of sodium-related chronic disease among adults aged 60 or older. The purpose of our study was to evaluate results from the first 2 years of the program, which modified recipes to reduce overall sodium levels through speed-scratch cooking (combining prepared food products with those made from scratch). INTERVENTION APPROACH: We modified recipes to reduce sodium content in 2 potato products served frequently as side dishes in distributive programs for older adults for congregate meals - those provided to groups in a community setting - and home-delivered meals. EVALUATION METHODS: We compared average sodium content of a 3-month menu cycle between 2 program years, the costs and consumer acceptance of recipe modifications, and consumer perceptions of product changes. Primary data included a nutrient analysis and key informant interviews. RESULTS: Approximately 2,000 distributive meal clients of CICOA Aging and In-Home Solutions were served reduced-sodium potato dishes over the 2 years of the intervention. From year 1 to year 2, the sodium content of scalloped potatoes was reduced by 65%, and the sodium content of mashed potatoes was reduced by 87%. Client acceptance of the modified recipes met the target threshold of a mean Likert-scale score of 3.75 out of 5.0, and the combined cost savings for both potato dishes was 45 cents per serving. Key informants noted the themes of economics of cost and labor, knowledge of how to identify reduced sodium options, and quality of the replacement food as essential factors for recipe modification. IMPLICATIONS FOR PUBLIC HEALTH: Using speed-scratch recipe modification for 2 potato dishes significantly reduced the sodium content of distributive meals for older adults. Speed-scratch recipe modification can be used as a tool to improve the nutritional value of meals and reduce the chronic disease burden of high-risk populations.
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Servicios de Alimentación , Comidas , Anciano , Culinaria , Humanos , Valor Nutritivo , SodioRESUMEN
PURPOSE: Developmental and epileptic encephalopathies (DEEs) are severe clinical conditions characterized by stagnation or decline of cognitive and behavioral abilities preceded, accompanied or followed by seizures. Because DEEs are clinically and genetically heterogeneous, next-generation sequencing, especially exome sequencing (ES), is becoming a first-tier strategy to identify the molecular etiologies of these disorders. METHODS: We combined ES analysis and international data sharing. RESULTS: We identified 11 unrelated individuals with DEE and de novo heterozygous truncating variants in the interferon regulatory factor 2-binding protein-like gene (IRF2BPL). The 11 individuals allowed for delineation of a consistent neurodevelopmental disorder characterized by mostly normal initial psychomotor development followed by severe global neurological regression and epilepsy with nonspecific electroencephalogram (EEG) abnormalities and variable central nervous system (CNS) anomalies. IRF2BPL, also known as enhanced at puberty protein 1 (EAP1), encodes a transcriptional regulator containing a C-terminal RING-finger domain common to E3 ubiquitin ligases. This domain is required for its repressive and transactivating transcriptional properties. The variants identified are expected to encode a protein lacking the C-terminal RING-finger domain. CONCLUSIONS: These data support the causative role of truncating IRF2BPL variants in pediatric neurodegeneration and expand the spectrum of transcriptional regulators identified as molecular factors implicated in genetic developmental and epileptic encephalopathies.
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Proteínas Portadoras/genética , Epilepsia/genética , Trastornos del Neurodesarrollo/genética , Proteínas Nucleares/genética , Convulsiones/genética , Adolescente , Adulto , Sistema Nervioso Central/diagnóstico por imagen , Sistema Nervioso Central/patología , Niño , Electroencefalografía , Epilepsia/diagnóstico por imagen , Epilepsia/fisiopatología , Femenino , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación , Trastornos del Neurodesarrollo/diagnóstico por imagen , Trastornos del Neurodesarrollo/fisiopatología , Fenotipo , Convulsiones/diagnóstico por imagen , Convulsiones/fisiopatología , Secuenciación del Exoma , Adulto JovenRESUMEN
BACKGROUND: Managing modern diabetes treatment requires efficient executive functions. Patients with attention-deficit/hyperactivity disorder (ADHD) and type 1 diabetes have poor metabolic control and present with ketoacidosis more often than patients without ADHD. OBJECTIVE: To assess whether patients with type 1 diabetes and with indications of executive problems met criteria for ADHD, and to investigate whether these patients had difficulties achieving metabolic control. METHODS: In a hospital-based study, including 3 pediatric departments at hospitals in Stockholm and Uppsala, Sweden, questionnaires regarding executive problems had been filled out by 12- to 18-year-old patients with type 1 diabetes and their parents. Out of 166 patients with completed questionnaires, 49 were selected for a clinical study due to reported executive problems/ADHD symptoms. However, 7 already had a diagnosis of ADHD, 21 denied follow-up, 8 did not respond, leaving 13 adolescents for the clinical assessment. RESULTS: Of the clinically assessed adolescents, 9 (6 girls) met criteria for ADHD. Patients who did not respond to the follow-up and patients who were diagnosed with ADHD within the study, showed to a larger extent than the other study groups high HbA1c levels (>70 mmol/mol, 8,6%). HbA1c >70 mmol/mol (8.6%) was associated with diagnosed ADHD (prior to or within the study), odds ratio 2.96 (95% confidence interval 1.02-8.60). CONCLUSION: Patients with type 1 diabetes and poor metabolic control should be assessed with regard to ADHD. There is a need for paying special attention to girls with poor metabolic control.
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Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/sangre , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Niño , Diabetes Mellitus Tipo 1/epidemiología , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Sistema de Registros , Encuestas y Cuestionarios , Suecia/epidemiologíaRESUMEN
The eyes of two glacial-relict populations of opossum shrimp Mysis relicta inhabiting the different photic environments of a deep, dark-brown freshwater lake and a variably lit bay of the Baltic Sea differ in their susceptibility to functional depression from strong light exposures. The lake population is much more vulnerable than the sea population. We hypothesized that the difference reflects physiological adaptation mechanisms operating on long time scales rather than genetically fixed differences between the populations. To test this, we studied how acclimation to ultra-slowly increased illumination (on time scales of several weeks to months) affected the resilience of the eyes to bright-light exposures. Light responses of whole eyes were measured by electroretinography, the visual-pigment content of single rhabdoms by microspectrophotometry and the structural integrity of photoreceptor cells by electron microscopy (EM). Slow acclimation mitigated and even abolished the depression of photoresponsiveness caused by strong light exposures, making a dramatic difference especially in the lake animals. Still, acclimation in the sea animals was faster and the EM studies suggested intrinsic differences in the dynamics of microvillar membrane cycling. In conclusion, we report a novel form of physiological adaptation to general light levels, effective on the time scale of seasonal changes. It explains part but not all of the differences in light tolerance between the lake and sea populations.
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Crustáceos/fisiología , Luz , Fenómenos Fisiológicos Oculares , Células Fotorreceptoras de Invertebrados/fisiología , Animales , Bahías , Electrorretinografía , Finlandia , Lagos , Microscopía Electrónica de Transmisión , Microespectrofotometría , Estimulación Luminosa , Factores de TiempoRESUMEN
Legume plants can obtain combined nitrogen for their growth in an efficient way through symbiosis with specific bacteria. The symbiosis between Rhizobium galegae and its host plant Galega is an interesting case where the plant species G. orientalis and G. officinalis form effective, nitrogen-fixing, symbioses only with the appropriate rhizobial counterpart, R. galegae bv. orientalis and R. galegae bv. officinalis, respectively. The symbiotic properties of nitrogen-fixing rhizobia are well studied, but more information is needed on the properties of the host plants. The Caucasus region in Eurasia has been identified as the gene centre (centre of origin) of G. orientalis, although both G. orientalis and G. officinalis can be found in this region. In this study, the diversity of these two Galega species in Caucasus was investigated to test the hypothesis that in this region G. orientalis is more diverse than G. officinalis. The amplified fragment length polymorphism fingerprinting performed here showed that the populations of G. orientalis and R. galegae bv. orientalis are more diverse than those of G. officinalis and R. galegae bv. officinalis, respectively. These results support the centre of origin status of Caucasus for G. orientalis at a genetic level. Analysis of the symbiosis-related plant genes NORK and Nfr5 reveals remarkable diversity within the Nfr5 sequence, although no evidence of adaptive evolution could be found.
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Galega/genética , Variación Genética , Genoma de Planta , Filogenia , Simbiosis/genética , Secuencia de Aminoácidos , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , ADN de Plantas/genética , Galega/microbiología , Datos de Secuencia Molecular , Rhizobium/fisiología , Federación de Rusia , Análisis de Secuencia de ADNRESUMEN
In viviparous species, a conflict over maternal resource allocation may arise between mothers and embryos, between siblings, and between maternal and paternal genes within an embryo due to relatedness asymmetries. We performed two experiments to study the effects of polyandry and brood relatedness on offspring growth in a placental fish (Heterandria formosa). Polyandry was beneficial as it increased the probability of pregnancy, possibly to avoid genetic incompatibility. However, females mated to four males produced offspring that had a longer maturation time than those of monandrous females. When within-brood relatedness was manipulated, the size of the newborn offspring decreased with time in low-relatedness treatment, whereas in highly related broods, offspring size was constant. Low within-brood relatedness may lead to less cooperative offspring in terms of resource extraction from the mother, which may lead to impaired development during gestation. Offspring conflict may thus reduce the benefits of polyandry in viviparous species.
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Ciprinodontiformes/fisiología , Placentación , Conducta Sexual Animal/fisiología , Viviparidad de Animales no Mamíferos , Alelos , Animales , Tamaño Corporal , Cruzamientos Genéticos , Ciprinodontiformes/genética , Femenino , Genotipo , Masculino , EmbarazoRESUMEN
Extracting DNA directly from micro-organisms living in soil is a crucial step for the molecular analysis of soil microbial communities. However, the use of a plethora of different soil DNA extraction protocols, each with its own bias, makes accurate data comparison difficult. To overcome this problem, a method for soil DNA extraction was proposed to the International Organization for Standardization (ISO) in 2006. This method was evaluated by 13 independent European laboratories actively participating in national and international ring tests. The reproducibility of the standardized method for molecular analyses was evaluated by comparing the amount of DNA extracted, as well as the abundance and genetic structure of the total bacterial community in the DNA extracted from 12 different soils by the 13 laboratories. High quality DNA was successfully extracted from all 12 soils, despite different physical and chemical characteristics and a range of origins from arable soils, through forests to industrial sites. Quantification of the 16S rRNA gene abundances by real time PCR and analysis of the total bacterial community structure by automated ribosomal intergenic spacer analysis (A-RISA) showed acceptable to good levels of reproducibility. Based on the results of both ring-tests, the method was unanimously approved by the ISO as an international standard method and the normative protocol will now be disseminated within the scientific community. Standardization of a soil DNA extraction method will improve data comparison, facilitating our understanding of soil microbial diversity and soil quality monitoring.
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ADN/aislamiento & purificación , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Microbiología del Suelo , Técnicas de Tipificación Bacteriana/métodos , Dermatoglifia del ADN/métodos , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , ADN Ribosómico/genética , ADN Ribosómico/aislamiento & purificación , ARN Ribosómico 16S/genética , Reproducibilidad de los ResultadosRESUMEN
INTRODUCTION: Cold ischemia time (CIT) influences long-term graft survival after deceased donor (DD) kidney transplantation. The aim of the present study was to identify factors that influenced CIT at our institution, seeking to lay ground for improvement. PATIENTS AND METHODS: Patients who underwent DD kidney transplantations from November 2008 to April 2009 were included in the study. In a prospective protocol the times for various events were registered. The 40 DD kidney transplantations included 26 "paired" kidneys from the same donor and 14 "single" kidneys. RESULTS: The mean CIT was 15.2 hours ± 4.2 hours (range, 7.0-23.9). "First kidney" was 13.3 hours ± 3.4 versus 19.2 ± 2.8 hours for the "second kidney" (P < .001). The waiting time for the operating room (OR) was 2.4 hours (range, 0-12 hours). Twenty-five percent of the patients waited more than 4 hours. Patients arriving at the hospital at the same time as or before the kidney retrieval showed a CIT of 13.4 ± 3.9 hours compared with 17.4 ± 3.4 hours for patients that arrived after the retrieved kidney (P < .01). CONCLUSION: We identified factors influencing CIT that could lay the foundation for improvement. An extended cooperation and exchange with another transplantation unit for the "second kidney" could reduce the CIT. To reduce the waiting time for OR at the hospital to less than 2 hours and to get the recipient into the hospital before the kidney arrives are efforts that could reduce CIT.
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Frío , Isquemia , Trasplante de Riñón , Riñón/irrigación sanguínea , Humanos , Suecia , Estudios de Tiempo y MovimientoRESUMEN
The magnitude of inbreeding depression is often larger in traits closely related to fitness, such as survival and fecundity, compared to morphological traits. Reproductive behaviour is also closely associated with fitness, and therefore expected to show strong inbreeding depression. Despite this, little is known about how reproductive behaviour is affected by inbreeding. Here we show that one generation of full-sib mating results in a decrease in male reproductive performance in the least killifish (Heterandria formosa). Inbred males performed less gonopodial thrusts and thrust attempts than outbred males (delta = 0.38). We show that this behaviour is closely linked with fitness as gonopodial performance correlates with paternity success. Other traits that show inbreeding depression are offspring viability (delta = 0.06) and maturation time of males (delta = 0.19) and females (delta = 0.14). Outbred matings produced a female biased sex ratio whereas inbred matings produced an even sex ratio.
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Endogamia , Peces Killi/genética , Conducta Sexual Animal , Animales , Femenino , MasculinoRESUMEN
OBJECTIVE: To study the diversity and phylogeny of Rhizobia strains from Sesbania cannabina in Jinshajiang arid river valley in Sichuan province, China. METHODS: We used numerical taxonomy, 16S rDNA PCR-Restriction fragment length polymorphism(RFLP), sequences analysis of 16S rDNA and Glutamine synthetaseII(GS II)genes. RESULTS: Based on the dendrograms generated from numerical taxonomy, the strains were clustered into 6 groups at the similarity of 93%. Four groups were closely related to type strains of R .tropici, R.etli, S. saheli, A .rubi respectively, and two groups were separated with type strains. The results of 16S rDNA PCR-RFLP were in good agreement with that of numerical taxonomy, only two separated groups showed some differences. SCAU176 and SCAU144 representing the strains of two separated groups were selected for sequence analysis .The results of 16S rDNA sequence indicated that SCAU176 and SCAU144 were related to type strains R. huautlense, and the homology coefficient with R. huautlense was 100% and 98.9% respectively. GS II sequence analysis revealed that SCAU176 and SCAU144 were clustered together, and the homology coefficient with the nearest type strains R. tropici was below 90%. CONCLUSION: Rhizobia of Sesbania cannabina in Jinshajiang arid river valley are highly diverse, they are closely related to Rhizobium, Sinorhizobium and Agrobacterium.
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Biodiversidad , Filogenia , Rhizobium/clasificación , Rhizobium/aislamiento & purificación , Ríos/microbiología , Nódulos de las Raíces de las Plantas/microbiología , Sesbania/microbiología , China , ADN Bacteriano/genética , ADN Ribosómico/genética , Sequías , Glutamato-Amoníaco Ligasa/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Rhizobium/genética , Análisis de Secuencia de ADNRESUMEN
Pomatoschistus minutus show paternal care in a resource defence mating system. We investigated the effect of nest-site availability on parasitic spawning. Each experimental pool contained four potentially nest-building males, four females and nests-sites in shortage (2) or excess (6). Both treatments were conducted in two populations; one with natural nest-sites in excess, one with a nest-site shortage. Microsatellite-DNA revealed that all nest-holders had fertilized most of the eggs they tended. Yet, 35% of the nests contained eggs fertilized by another male and 14.4% of the males had performed parasitic spawning. There was no site or treatment effect. Several females spawned in two nests, which coincided with parasitic spawnings, suggesting a cost to the nest-holder in terms of lost mating success. Nest-holders with and without eggs and non-nesting males all spawned parasitically, generating a significantly lower opportunity for sexual selection compared to if there had been no parasitic spawning.
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Ambiente , Comportamiento de Nidificación , Perciformes/fisiología , Conducta Sexual Animal , Animales , Conducta Competitiva , Femenino , Fertilización , Masculino , Modelos Biológicos , Perciformes/genética , Selección GenéticaRESUMEN
PREFACE: Normal childbirth has become jeopardized by inexorably rising interventions around the world. In many countries and settings, cesarean surgery, labor induction, and epidural analgesia continue to increase beyond all precedent, and without convincing evidence that these actions result in improved outcomes (1,2). Use of electronic fetal monitoring is endemic, despite evidence of its ineffectiveness and consequences for most parturients (1,3); ultrasound examinations are too often done unnecessarily, redundantly, or for frivolous rather than indicated reasons (4); episiotomies are still routine in many settings despite clear evidence that this surgery results in more harm than good (5); and medical procedures, unphysiological positions, pubic shaving and enemas, intravenous lines, enforced fasting, drugs, and early mother-infant separation are used unnecessarily (1). Clinicians write and talk about the ideal of evidence-based obstetrics, but do not practice it consistently, if at all. Why do women go along with this stuff? In this Roundtable Discussion, Part 1, we asked some maternity care professionals and advocates to discuss this question.
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Parto Obstétrico/métodos , Medicina Basada en la Evidencia , Aceptación de la Atención de Salud , Defensa del Paciente , Calidad de la Atención de Salud , Analgesia Epidural/estadística & datos numéricos , Cesárea/estadística & datos numéricos , Parto Obstétrico/efectos adversos , Episiotomía/efectos adversos , Episiotomía/estadística & datos numéricos , Femenino , Monitoreo Fetal/estadística & datos numéricos , Humanos , Trabajo de Parto Inducido/estadística & datos numéricos , Relaciones Médico-Paciente , EmbarazoRESUMEN
Within administrative surveying work in Sweden, a transition to a client-centered team-based organization was made during 1998. The aim of this study was to describe the employees' perceptions and expectations of job and organizational practices when working as a generalist in a client-centered team-based organization; job and organizational practices and well-being and effectiveness measures were examined when introducing a team-based organization. Interventions such as courses in how to cope with the role of a generalist, how to increase service to clients, education in technology, law and economics, as well as computer information support, were ongoing at the time of the study. The Team Work Profile and QPS Nordic questionnaires were used. All the surveyors in five regions in Sweden participated, in total 640 surveyors. The transition to a client-centered team-based organization was expected to improve job control and job content but at the same time lead to impairments in job climate and group cohesion. Distress was associated with negative future expectations of the organization. High job control and group cohesion were the central contributors towards growth in personal competence and social effectiveness of teamwork. Both internal and external client-related activities of team and organization were in focus during the transition.
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Equipos de Administración Institucional , Aprendizaje , Trabajo/psicología , Conducta Cooperativa , Humanos , Relaciones Interpersonales , Satisfacción en el Trabajo , Estrés Psicológico , Encuestas y Cuestionarios , SueciaRESUMEN
This paper explores the relationship between the genetic diversity of rhizobia and the morphological diversity of their plant hosts. Rhizobium galegae strains were isolated from nodules of wild Galega orientalis and Galega officinalis in the Caucasus, the center of origin for G. orientalis. All 101 isolates were characterized by genomic amplified fragment length polymorphism fingerprinting and by PCR-restriction fragment length polymorphism (RFLP) of the rRNA intergenic spacer and of five parts of the symbiotic region adjacent to nod box sequences. By all criteria, the R. galegae bv. officinalis and R. galegae bv. orientalis strains form distinct clusters. The nod box regions are highly conserved among strains belonging to each of the two biovars but differ structurally to various degrees between the biovars. The findings suggest varying evolutionary pressures in different parts of the symbiotic genome of closely related R. galegae biovars. Sixteen R. galegae bv. orientalis strains harbored copies of the same insertion sequence element; all were isolated from a particular site and belonged to a limited range of chromosomal genotypes. In all analyses, the Caucasian R. galegae bv. orientalis strains were more diverse than R. galegae bv. officinalis strains, in accordance with the gene center theory.
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Galega/microbiología , Variación Genética , Rhizobium/clasificación , Simbiosis , Dermatoglifia del ADN/métodos , ADN Bacteriano/análisis , ADN Espaciador Ribosómico/análisis , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Rhizobium/genética , Rhizobium/aislamiento & purificación , Federación de RusiaRESUMEN
The genetic diversity among 95 isolates from Astragalus adsurgens was investigated using molecular biological methods. All of the isolates and 24 reference strains could be differentiated by AFLP, REP-, ERIC- and BOX-PCR fingerprinting analysis. By cluster analysis of the data, 31 AFLP and 38 Rep-PCR genomic groups were delineated, indicating considerable genetic diversity among the isolates. Fifty-four representative strains were further analyzed by RFLP of PCR-amplified 16S and 23S rDNA, revealing 26 rDNA genotypes among the isolates. The phylogenetic relationship of the isolates was determined by partial sequencing of 16S rRNA genes of 16 strains. The results suggest that the A. adsurgens rhizobia belong to the genera Agrobacterium, Mesorhizobium, Rhizobium and Sinorhizobium.
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Planta del Astrágalo/microbiología , Variación Genética , Rhizobiaceae/genética , China , Dermatoglifia del ADN , ADN Ribosómico , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
AFLP fingerprints of Rhizobium galegae strains that infect Galega orientalis and Galega officinalis obtained from different geographical sources, and of taxonomically diverse rhizobia representing the recognized species, were generated. Comparisons of the fingerprints from fluorescent labeled AFLP products using capillary electrophoresis on ABI prism 310, slab gel electrophoresis on ABI prism 377 genetic analyzers and silver staining were in good agreement. All methods delineated the G. orientalis strains from G. officinalis strains, the G. orientalis strains formed a tight cluster whereas the G. officinalis strains seem to show a greater level of genetic diversity. Comparison of fluorescent AFLP with other detection methods revealed that fluorescent labeling is more sensitive and practical, in addition, the deleterious effect of radioactivity associated with 32P-labeling, the delicate process of blotting polyacrylamide gels or the tedious procedure of silver staining can be avoided. The automated system facilitated a large number of runs at a time and the subsequent analysis of the data by generating exportable raw data. The congruency of the experiments was analyzed using the Bionumerics software.
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Dermatoglifia del ADN/métodos , Galega/microbiología , Variación Genética , Rhizobiaceae/genética , Dermatoglifia del ADN/instrumentación , Filogenia , Rhizobiaceae/aislamiento & purificación , SimbiosisRESUMEN
Alternative mating strategies are common in nature and are generally thought to increase the intensity of sexual selection. However, cuckoldry can theoretically decrease the opportunity for sexual selection, particularly in highly polygamous species. We address here the influence of sneaking (fertilization thievery) on the opportunity for sexual selection in the sand goby Pomatoschistus minutus, a marine fish species in which males build and defend nests. Our microsatellite-based analysis of the mating system in a natural sand goby population shows high rates of sneaking and multiple mating by males. Sneaker males had fertilized eggs in approximately 50% of the assayed nests, and multiple sneakers sometimes fertilized eggs from a single female. Successful males had received eggs from 2 to 6 females per nest (mean = 3.4). We developed a simple mathematical model showing that sneaking in this polygynous sand goby population almost certainly decreases the opportunity for sexual selection, an outcome that contrasts with the usual effects of cuckoldry in socially monogamous animals. These results highlight a more complex and interesting relationship between cuckoldry rates and the intensity of sexual selection than previously assumed in much of the literature on animal mating systems.
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Peces/genética , Peces/fisiología , Selección Genética , Conducta Sexual Animal , Animales , Femenino , Marcadores Genéticos , Masculino , Repeticiones de Microsatélite/genéticaRESUMEN
Twenty-six Rhizobium galegae strains, representing the center of origin of the host plants Galega orientalis and G. officinalis as well as other geographic regions, were used in a polyphasic analysis of the relationships of R. galegae strains. Phage typing, lipopolysaccharide (LPS) profiling, pulsed field gel electrophoresis (PFGE) profiling and rep-PCR (use of repetitive sequences as PCR primers for genomic fingerprinting) with REP and ERIC primers investigated nonsymbiotic properties, whereas plasmid profiling and hybridisation with a nif gene probe, and with nodB, nodD, nod box and an IS sequence from the symbiotic region as probes, were used to reveal the relationships of symbiotic genes. The results were used in pairwise calculations of distances between the strains, and the distances were visualised as a dendrogram. Indexes of association were compared for all tests pooled, and for chromosomal tests and symbiotic markers separately, to display the input of the different categories of tests on the grouping of the strains. Our study shows that symbiosis related genetic traits in R. galegae divide strains belonging to the species into two groups, which correspond to strains forming an effective symbioses with G. orientalis and G. officinalis respectively. We therefore propose that Rhizobium galegae strains forming an effective symbiosis with Galega orientalis are called R. galegae bv. orientalis and strains forming an effective symbiosis with Galega officinalis are called R. galegae bv. officinalis.