ABSTRACT
OBJECTIVE@#Campylobacter jejuni NCTC11168 is commonly used as a standard strain for flagellar biosynthesis research. In this report, two distinguished phenotypic isolates (CJ1Z, flhA mutant strain, lawn; CJ2S, flhA complemented strain, normal colony) appeared during laboratory passages for NCTC11168.@*METHODS@#Phenotypic assessments, including motility plates, transmission electron microscopy, biofilm formation assay, autoagglutination assay, and genome re-sequencing for these two isolates (CJ1Z, flhA mutant strain; CJ2S, flhA complemented strain) were carried out in this study.@*RESULTS@#Transmission electron microscopy revealed that the flagellum was lost in CJ1Z. Phenotypic assessments and genome sequencing of the two isolates were performed in this study. The capacity for biofilm formation, colony auto-agglutination, and isolate motility was reduced in the mutant CJ1Z. Comparative genomic analysis indicated a unique native nucleotide insertion in flhA (nt, 2154) that caused the I719Y and I720Y mutations and early truncation in flhA.@*CONCLUSION@#FlhA has been found to influence the expression of flagella in C. jejuni. To the best of our knowledge, this is the first study to describe the function of the C-terminal of this protein.
Subject(s)
Campylobacter jejuni/genetics , Bacterial Proteins/metabolism , Mutation , Biological Variation, PopulationABSTRACT
Introduction: Huntington's disease (HD) is a neurodegenerative disorder caused by CAG expansion repeats in the HTT gene. Usually, the symptoms start to manifest in mid-adulthood. In about 5% of cases, however, the signs begin before the age of 20 years. These cases are known as juvenile HD (JHD). Objective: here we report a case series of JHD from Amazonas, a state where data are scarce due to the restricted access to specialized medical assistance for diagnosis and care. Case series: the patients were attended by neurologists specialized in movement disorders at Manaus. Two cases manifested the disease in childhood (6 and 7 years old) and two cases, in adolescence (12 and 16 years old). All cases showed dystonia and parkinsonism as predominant motor disorders. Moreover, signs of cognitive decline, depression, and psychosis were observed in all patients. Conversely, cerebellar signs, gait disturbances, seizures, and some psychiatric symptoms were variable among the cases. Expansion size varied from 66 to 84 to CAG repeats and the difference in age at onset between parent and child varied from 23 to 43 years. Conclusion: to our knowledge, these are the first clinical reports of JHD in northern Brazil. These cases illustrate the variability in clinical phenotypes and genetic features of JHD cases. Furthermore, they can contribute to the awareness of HD here, both by professionals and the public in general.
Introdução: a doença de Huntington (DH) é um distúrbio neurodegenerativo causado pela expansão de repetições CAG no gene HTT. Geralmente, os sintomas começam a se manifestar na vida adulta tardia. Em cerca de 5% dos casos, no entanto, os sinais começam antes da idade de 20 anos. Esses casos são conhecidos como DH juvenil (DHJ). Objetivo: neste estudo, nós reportamos uma série de casos de DHJ do Amazonas, um estado onde os dados ainda são escassos devido ao acesso restrito à assistência médica especializada para o diagnóstico e cuidado. Série de casos: os pacientes foram atendidos por neurologistas especializados em transtornos do movimento em Manaus. Dois casos manifestaram a doença na infância (6 e 7 anos) e dois casos, na adolescência (12 e 16 anos). Todos os casos apresentaram distonia e parkinsonismo como sintomas motores predominantes. Sinais de declínio cognitivo, depressão e psicose também foram observados em todos os pacientes. Por outro lado, sinais cerebelares, distúrbios da marcha, convulsões e alguns sintomas psiquiátricos foram variáveis entre os casos. O tamanho da expansão CAG variou de 66 a 84 repetições e a diferença na idade de início dos sintomas entre pais e filhos variou de 23 a 43 anos. Conclusão: ao nosso conhecimento, estes são os primeiros relatos clínicos da DHJ na região Norte. Esses casos ilustram a variabilidade nos fenótipos clínicos e nas características genéticas dos casos de DHJ. Além disso, eles podem contribuir para a conscientização da DH na região, tanto pelos profissionais quanto pelo público geral.
Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Huntington Disease , Trinucleotide Repeat Expansion , Anticipation, Genetic , Heredodegenerative Disorders, Nervous System , Biological Variation, PopulationABSTRACT
RESUMEN El haba es una leguminosa asociada a sistemas campesinos de clima frío. En Colombia, se cultiva, principalmente, en el departamento de Nariño, donde se ha visto reducida el área y el número de materiales sembrados, debido a la disminución en los niveles de rendimiento del cultivo y la agresividad de los problemas fitosanitarios. Este estudio evaluó la diversidad de esta leguminosa, a partir de la forma y color de la semilla, en una colección de 60 accesiones de haba, discriminadas en siete variedades. Mediante el procesamiento de imágenes digitales y medición manual, se determinó la longitud polar (LP), longitud ecuatorial (LE), relación LP/LE, área (AR), grosor (GR) y peso de cien semillas (P100); además, se calcularon los parámetros de color, basados en la escala CIELab (L*, a* y b*). Las variables, se analizaron con estadística descriptiva, correlación de Pearson y el método multivariado de componentes principales (ACP). Los resultados identificaron alta diversidad de fenotipos, caracterizando, cuantitativamente, las siete variedades. Se presentó correlación alta entre las variables LP, LE y AR, igualmente, entre L* y b*. Con el biplot de los resultados de ACP, se ratificó la variabilidad de la colección y posibilitó generar una agrupación preliminar. La investigación, se puede tomar en cuenta como base para el desarrollo de trabajos de conservación y de evaluación agronómica de esta leguminosa.
ABSTRACT Fava bean is a legume associated with cold climate farming systems. In Colombia, it is grown mainly in the department of Nariño, where the area and number of planted materials have been reduced due to the decrease in crop yield levels and the aggressiveness of phytosanitary problems. This study evaluated the diversity of this legume based on seed shape and color in a collection of 60 bean materials divided into seven varieties. Through digital image processing and manual measurement, polar length (LP), equatorial length (LE), LP/LE ratio, area (AR), thickness (GR) and hundred seed weight (P100) were determined, and color parameters based on the CIELab scale (L*, a* and b*) were calculated. The variables were analyzed with descriptive statistics, Pearson's correlation and the multivariate principal component method (PCA). The results identified a high diversity of phenotypes, quantitatively characterizing the seven varieties. There was a high correlation between the variables LP, LE and AR, as well as between L* and b*. The biplot of the PCA results confirmed the variability of the collection and made it possible to generate a preliminary grouping. The research can be taken into account as a basis for the development of conservation and agronomic evaluation of this legume.
ABSTRACT
Resumen Introducción: A pesar de su importancia en el rendimiento de la natación y la eficacia biológica individual, la forma del cuerpo y las variaciones de tamaño en respuesta a la velocidad del flujo de agua siguen siendo desconocidas para la mayoría de los peces migratorios de agua dulce en el Neotrópico. Objetivo: Contrastar la hipótesis de variación fenotípica en el tamaño y la conformación del cuerpo de dos especies de peces dulceacuícolas que enfrentan cambios de velocidad a través de sus migraciones en dos ríos pertenecientes a una cuenca neotropical. Métodos: Se utilizó la morfometría geométrica basada en hitos para estudiar las variaciones en el tamaño y la conformación del cuerpo para dos especies de peces Curimata mivartii y Pimelodus grosskopfii en hábitats lóticos y lénticos de la cuenca Colombiana del Magdalena-Cauca. Resultados: Los individuos de C. mivartii de dos hábitats lóticos fueron similares en tamaño y significativamente más grandes que los del hábitat léntico, mientras que los individuos de P. grosskopfii fueron similares en ambos hábitats. Ambas especies mostraron cuerpos más hidrodinámicos en hábitats lóticos y formas corporales más robustas en hábitats lénticos. Conclusión: Ambas especies exhiben cambios fenotípicos en la forma del cuerpo concordantes con las predicciones previas sobre las variaciones morfológicas de los peces. Esta información es relevante para predecir cambios en respuesta a la heterogeneidad ambiental, especialmente inducidos por actividades antropogénicas que cambian las velocidades del agua en el río.
Abstract Introduction: Despite their importance in swimming performance and individual fitness, body shape and size variations in response to water flow velocity remain unknown for most migratory freshwater fishes in the Neotropics. Objective: Test the hypothesis of phenotypic variation in the size and body shape of two species of freshwater fishes that encounter changes in water velocity across their migrations in two rivers that belong to a single Neotropical basin. Methods: Landmark-based geometric morphometrics was used to study variations in body size and shape for the fish species Curimata mivartii and Pimelodus grosskopfii in lotic and lentic habitats of the Colombian Magdalena-Cauca Basin. Results: Individuals of C. mivartii from two lotic habitats were similar in size and both were significantly bigger than those from lentic habitats, whereas individuals of P. grosskopfii were similar in size in both habitats. Both species showed more streamlined bodies in lotic habitats and deeper body shapes in lentic habitats. Conclusions: Both species exhibit phenotypic changes in body shape concordant with previous predictions on morphological variations of fishes. This information is relevant to predict changes in response to environmental heterogeneity, especially those induced by anthropogenic activities that change the water velocity in the river.
Subject(s)
Animals , Catfishes/anatomy & histology , Fishes , ColombiaABSTRACT
The paper aimed at studying the morphometric variation in eight natural populations of two rare Sideritis species occurring in Bulgaria. Thirteen measured traits and four ratios were used to reveal the degree and distribution of variation. Most traits exhibited moderate to high variation and the most differentiating one was the length of the acumen. Cluster analysis and Principal component analysis revealed that the two taxa, S. scardica and S. syriaca are well distinguished but the population Chervenata stena, classified as S. scardica differed significantly from the remaining ones of the same species. Results of the morphometric study indicate the necessity of further studies for revealing the taxonomic relationships among the taxa.
El manuscrito teniÌa como objetivo estudiar la variacioÌn morfomeÌtrica en ocho poblaciones naturales de dos especies raras de Sideritis que crecen en Bulgaria. Se utilizaron trece rasgos medidos y cuatro relaciones para revelar el grado y la distribucioÌn de la variacioÌn. La mayoriÌa de los rasgos mostraron una variacioÌn de moderada a alta y la maÌs diferenciadora fue la longitud del acumen. El anaÌlisis de conglomerados y el anaÌlisis de componentes principales revelaron que los dos taxas, S. scardica y S. syriaca estaÌn bien diferenciados, pero la poblacioÌn de Chervenata stena, clasificada como S. scardica, diferiÌa significativamente de las restantes de la misma especie. Los resultados del estudio morfomeÌtrico indican la necesidad de estudios adicionales para revelar las relaciones taxonoÌmicas entre los taxones.
Subject(s)
Phenotype , Sideritis/anatomy & histology , Anatomic Variation , Bulgaria , Analysis of Variance , Principal Component AnalysisABSTRACT
This article reviews the production of different phenotypes from the same genotype in the same environment by stochastic cellular events, nonlinear mechanisms during patterning and morphogenesis, and probabilistic self-reinforcing circuitries in the adult life. These aspects of phenotypic variation are summarized under the term‘stochastic developmental variation’ (SDV) in the following. In the past, SDV has been viewed primarily as a nuisance, impairing laboratory experiments, pharmaceutical testing, and true-to-type breeding. This article also emphasizes the positive biological effects of SDV and discusses implications for genotype-to-phenotype mapping, biological individuation, ecology, evolution, and applied biology. There is strong evidence from experiments with genetically identical organisms performed in narrowly standardized laboratory set-ups that SDV is a source of phenotypic variation in its own right aside from genetic variation and environmental variation. It is obviouslymediated bymolecular and higher-order epigeneticmechanisms. Comparison of SDV in animals, plants, fungi, protists, bacteria, archaeans, and viruses suggests that it is a ubiquitous and phylogenetically old phenomenon. In animals, it is usually smallest for morphometric traits and highest for life history traits and behaviour. SDV is thought to contribute to phenotypic diversity in all populations but is particularly relevant for asexually reproducing and genetically impoverished populations, where it generates individuality despite genetic uniformity. In each generation, SDV produces a range of phenotypes around a well-adapted target phenotype, which is interpreted as a bet-hedging strategy to cope with the unpredictability of dynamic environments. At least some manifestations of SDV are heritable, adaptable, selectable, and evolvable, and therefore, SDV may be seen as a hitherto overlooked evolution factor. SDV is also relevant for husbandry, agriculture, and medicine because most pathogens are asexuals that exploit this third source of phenotypic variation tomodify infectivity and resistance to antibiotics. Since SDV affects all types of organisms and almost all aspects of life, it urgently requires more intense research and a better integration into biological thinking.