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2.
Rev. biol. trop ; 64(3): 1057-1065, jul.-sep. 2016. tab, ilus
Article in English | LILACS | ID: biblio-958195

ABSTRACT

Abstract:Community structure and composition are dictated by evolutionary and ecological assembly processes which are manifested in signals of, species diversity, species abundance and species relatedness. Analysis of species coexisting relatedness, has received attention as a tool to identify the processes that influence the composition of a community within a particular habitat. In this study, we tested if microbialite genetic composition is dependent on random events versus biological/abiotical factors. This study was based on a large genetic data set of two hypervariable regions (V5 and V6) from previously generated barcoded 16S rRNA amplicons from nine microbialite communities distributed in Northeastern, Central and Southeastern Mexico collected in May and June of 2009. Genetic data of the most abundant phyla (Proteobacteria, Planctomycetes, Verrucomicrobia, Bacteroidetes, and Cyanobacteria) were investigated in order to state the phylogenetic structure of the complete communities as well as each phylum. For the complete dataset, Webb NTI index showed positive and significant values in the nine communities analysed, where values ranged from 31.5 in Pozas Azules I to 57.2 in Bacalar Pirate Channel; meanwhile, NRI index were positive and significant in six of the nine communities analysed with values ranging from 18.1 in Pozas Azules I to 45.1 in Río Mesquites. On the other hand, when comparing each individual phylum, NTI index were positive and significant in all groups, except in Cyanobacteria for which positive and significant values were only found in three localities; finally, NRI index was significant in only a few of the comparisons performed. The results suggest that habitat filtering is the main process that drives phylogenetic structure in bacterial communities associated to microbialites with the exception of Cyanobacteria where different lineages can contribute to microbialite formation and growth. Rev. Biol. Trop. 64 (3): 10571065. Epub 2016 September 01.


ResumenLa estructura y composición de las comunidades son determinadas por procesos evolutivos y ecológicos que se manifiestan en señales de diversidad, abundancia y la relación de especies. El análisis de la relación de especies que coexisten ha recibido atención como una herramienta para identificar los procesos que influyen en la composición de una comunidad dentro de un hábitat particular. En este estudio, evaluamos si la composición genética de bacterias microbialíticas depende de acontecimientos al azar vs factores biológicos/ abióticos. Este estudio se basa en un conjunto de datos genéticos de dos regiones hipervariables (V5 y V6) de gen 16S rRNA generados previamente de nueve comunidades de microbialitos distribuidos en el Noreste, Centro y Sureste de México, recolectados en mayo y junio 2009. Los datos genéticos de los filos más abundantes (Proteobacteria, Planctomycetes, Verrucomicrobia, Bacteroidetes y Cyanobacteria) fueron analizados para determinar la estructura filogenética de la comunidad y de cada filo por separado. Para el análisis conjunto, el índice NTI de Webb mostró valores positivos y significativos en las nueve comunidades analizadas, en donde los valores oscilaron entre 31.5 en Pozas Azules I y 57.2 en el Canal Pirata en Bacalar; en contraste, los valores del índice NRI fueron positivos y significativos en seis de las nueve comunidades analizadas con valores oscilando desde 18.1 en Pozas Azules I hasta 45.1 en Río Mezquites. Por otro lado, en la comparación de cada filo individual, el índice NTI fue positivo y significativo en todos los grupos excepto en Cyanobacteria, en donde valores positivos y significativos fueron encontrados sólo en tres localidades; finalmente, el índice NRI fue significativo sólo en unas cuantas de las comparaciones realizadas. Los resultados sugieren que el filtrado del hábitat es el proceso principal que determina la estructura filogenética de las comunidades bacterianas asociadas a microbialitos con la excepción de las cianobacterias en donde diferentes linajes pueden contribuir a la formación y crecimiento del microbialito.


Subject(s)
Phylogeny , Bacteria/genetics , Archaea/genetics , Ecosystem , Eukaryota/genetics , Reference Values , Bacteria/growth & development , DNA, Bacterial , RNA, Ribosomal, 16S , Archaea/growth & development , Eukaryota/growth & development , DNA Barcoding, Taxonomic/methods , Phylogeography/methods , Mexico
3.
The Korean Journal of Nutrition ; : 234-245, 2009.
Article in Korean | WPRIM | ID: wpr-655693

ABSTRACT

Nutritional assessment for the elderly can identify health status and morbidity. However, development of Nutritional Risk Index (NRI) remains limited for elderly because of difficulties in understanding physiological mechanism of elderly. This study was performed to analyze and develop Nutritional Risk Index for Korean elderly Women (Geriatric Nutritional Risk Index, GNRI). Based on literature review, factors for NRI were identified and indices were assessed by a cross-sectional survey. The survey involved Korean elderly women (> or = 60, n = 94) in Gwangju area, and sociodemographics, lifestyle characteristics, health conditions, dietary intakes based on 24h- recall, anthropometric measures (wt, ht, BMI, waist, hip, WHR, body protein, body fat, abdominal fat, and triceps skinfold thickness), and clinical biochemistry parameters (systolic blood pressure, diastolic blood pressure, cholesterol, HDL-cholesterol, triglyceride, total protein, albumin, prealbumin, hemoglobin, hematocrit, fasting blood glucose, HbA1c, ferritin, Zn, Ca, Na, K, Vit E, Vit B12, folate, C-reactive protein) were examined relation to nutritional risk index. Based on literature review and data analyses, three NRIs were categorized (NRI I, NRI II, NRI III) and used for further analysis. NRI I was related to having metabolic syndrome, NRI II was related to serum albumin and body weight, and NRI III was related to food habit and health concerns. Abdominal fat (%) of elderly was correlated with each NRIs. NRI II was correlated with nutritional deficiency and higher tendency of inflammatory response, and NRI III was correlated with nutritional status which tend to be lower on aging (protein, folate, Vit B12). NRI can serve as a useful tools in assessing health risk and nutritional status. Some modification of items in NRI and validity study are need to apply to Korean elderly.


Subject(s)
Aged , Female , Humans , Abdominal Fat , Adipose Tissue , Aging , Biochemistry , Blood Glucose , Blood Pressure , Body Weight , Cholesterol , Cross-Sectional Studies , Delivery of Health Care , Fasting , Ferritins , Folic Acid , Feeding Behavior , Hematocrit , Hemoglobins , Hip , Life Style , Malnutrition , Nutrition Assessment , Nutritional Status , Prealbumin , Serum Albumin , Statistics as Topic
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