Simple and sensitive spectrophotometric method for estimating the nitrogen-fixing capacity of bacterial cultures.

Biological nitrogen fixation (BNF) is a process through which a group of microorganisms called diazotrophs convert unassimilable atmospheric nitrogen into ammonia. In aqueous media, ammonia yields ammonium ions that can be assimilated by microorganisms and plants. To reduce the application of nitrogen fertilizers and their environmental effects, an alternative approach toward sustainable agriculture is the induction of artificial associations between diazotrophs and plants. This has led to increased interest in the search for microorganisms capable of supplying nitrogen to crops. This article presents a simple, economical, and sensitive spectrophotometric method for estimating the BNF capacity of bacteria cultured in a liquid NFb medium, based on the variation of absorbance caused by the change in color of bromothymol blue in the culture medium. The structure and color of this indicator are modified by pH shifts, which depend on the concentration of fixed ammonium ions.•The nitrogen concentration (estimated from the ammonium in the culture medium) showed a positive correlation (R 2 = 0.984) with the absorbance measured at 610 nm. The regression equation obtained through the origin was y = 0.009682140x, where y is the absorbance and x is the nitrogen concentration in the culture medium.•The methods used at present to measure the efficiency of BNF require expensive equipment, which may not be affordable for many laboratories or companies working in this field.•This technique can be used for pure bacterial strains and microbial consortia from soil or commercial products.

Body architecture of Holstein Friesian and black frison biotypes used in south Chilean dairy farms / Arquitectura corporal de biotipos bovinos Holstein Friesian y overo negro utilizados en predios lecheros del sur de Chile

The objective of the present work was to characterize the morphostructural architecture of bovine biotypes that are mostly used in milk production in southern Chile. Measurements were carried out in 26 dairy farms located in the provinces of Osorno and Ranco, in Los Lagos and Los Ríos regions, respectively. In each farm, four animals were randomly selected from the herd; 104 four year-old cows were measured. Cows were classified into four biotypes: Holstein Friesian (HD), Overo Negro (OD), hybrid Friesian Holstein (HM) and hybrid Overo Negro (OM), according to the opinion of the owner or administrator. Nine body measurements were taken: head length (HL), head width (HW), withers height (WH), rump height (RH), bicostal diameter (BD), longitudinal diameter (LD), rump width (RW), rump length (RL) and dorso-sternal diameter (DED). Data were analyzed by principal component analysis (PCA) and the Fisher LSD test. The evaluated animals seem to converge around a basic architecture derived from cultural selection patterns regardless of the racial biotype. This architecture could be typical of grazing systems or be influenced by aspects of selection additional to those directly related to production. The data suggest that the body architecture of the dairy cattle evaluated would respond to selection patterns more than to racial biotypes. It was also seen that measures such as DED, RW and LD have a greater incidence than the other variables within the observed common selection patterns. Finally, within the evaluated animal population, two selection patterns coexist, one represented by small size body architecture and another one that, although despite its larger dimensions, also represents a small dairy animal in comparison to the sizes reported for Holstein Friesian breed in other areas.

El objetivo de este trabajo fue caracterizar la arquitectura morfoestructural de los biotipos bovinos que mayoritariamente se utilizan en la producción de leche en el sur de Chile. Para ello se realizaron evaluaciones en 26 predios lecheros ubicados en las provincias de Osorno y Ranco, en las regiones de Los Lagos y Los Ríos, respectivamente. Se midieron 104 animales clasificados en cuatro biotipos según lo declarado por los ganaderos: Holstein Friesian (HD), Overo negro (OD) y cruzamientos de Holstein Friesian (HM) y Overo Negro (OM). En cada animal se determinaron nueve medidas corporales: longitud de la cabeza (HL), ancho de la cabeza (HW), alzada a la cruz (WH), alzada a la grupa (RH), diámetro bicostal (BD), diámetro longitudinal (LD), ancho de la grupa (RW), longitud de la grupa (RL) y diámetro dorso-esternal (DED). Los datos se analizaron mediante análisis de componentes principales (PCA) y el test de Fischer LSD, usando para ello el programa XLstat pro. De acuerdo a los resultados se puede concluir que, independiente del biotipo racial, los animales evaluados parecen converger en torno a una arquitectura básica derivada de patrones de selección fenotípica con un componente cultural que pudiera ser propia de los sistemas de pastoreo, o influenciada por aspectos de selección adicionales a los relacionados directamente a la producción. En este sentido, los datos indican que la arquitectura corporal del ganado lechero respondería más a patrones de selección que a biotipos raciales. También se apreció que la profundidad (DED), el ancho de grupa (RW) y el largo (LD) presentan una mayor incidencia que las demás variables evaluadas dentro de los patrones de selección común observados. Finalmente, fue posible apreciar que al interior de la población animal evaluada coexisten dos patrones de selección. Uno representado por una arquitectura corporal de pequeño tamaño y otro que, si bien exhibe mayores dimensiones, también representa un tipo de animal lechero de menor tamaño en comparación a las dimensiones que alcanzan los biotipos relacionados a la raza Holstein Friesian en otras zonas.

Population differentiation in the body architecture of creole goats in the semi arid region of Chile / Diferenciación poblacional en la arquitectura corporal de cabras criollas en la región semiárida de Chile

The present study aimed to assess the degree of body architecture differentiation between Creole goats, two introduced breeds and their hybrids in semi arid areas of the north of Chile. The study was carried out between 2012 and 2015. One hundred and eighty five adult female goats belonging to 17 herds from the Coquimbo region were used. Ten animals of the Saanen breed and 10 animals of the Anglo nubian breed belonging to two hatcheries and 165 Creole and hybrid goats belonging to small farmers were measured. The animals were categorized into pure breed (20), hybrid (52) and creole (113). Eight body measurements were taken: head length (HL), head width (HW), longitudinal diameter (LD), bicostal diameter (BD), dorsal-sternal diameter (DSD), rump width (RW), rump length (RL) and whithers height (WH). Data were submitted to principal component analysis (PCA) and Fisher LSD test, using the XLSTAT-Pro Statistic software. The analysis indicated the existence of homogeneity subsets within the population, without a common architectural pattern for the entire population. The Creole biotype showed a smaller body architecture than the two breeds and hybrids with which it was compared, which could be an adaptative result. It is possible to assess that the Creole biotype has a differentiated body architecture with respect to the introduced goat breeds and the animals hybridized in different proportions. In addittion, it was observed that Creole goats maintain distinctive characteristics and they are differentiable even of the individuals with different degrees of hybridization.

El presente estudio tuvo por objetivo identificar si existe diferenciación en la arquitectura corporal entre caprinos Criollos, razas introducidas y rebaños hibridados con las mismas. El estudio se llevó a cabo entre 2012 y 2015 en la región de Coquimbo, Chile. Ciento ochenta y cinco cabras fueron estudiadas, pertenecientes a 17 rebaños distintos. Se midieron 10 animales de raza Saanen y 10 animales de raza Anglo nubian presentes en dos criaderos, y 165 animales Criollos e híbridos en predios de productores. Ocho medidas corporales fueron determinadas: longitud de la cabeza (HL), ancho de la cabeza (HW), diámetro longitudinal (LD), diámetro bicostal (BD), diámetro dorso-esternal (DSD), ancho de la grupa (RW), longitud de la grupa (RH) y alzada a la cruz (WH). Los datos de medidas se analizaron mediante análisis de componentes principales (PCA) y test LSD de Fischer con el programa estadístico XLSTAT Pro. Los resultados indican que las diferencias entre variables refllejan la existencia de subcojuntos de homogeneidad dentro de la población, no apreciándose un patron arquitectónico común para toda la población. De esta manera, el biotipo Criollo presenta una arquitectura corporal más reducida que las razas con las que se compara en este estudio, lo cual pudiera ser una respuesta adaptativa. En este sentido, es posible afirmar que el biotipo Criollo presenta una arquitectura corporal diferenciada respecto de las razas introducidas a la región y a los animales hibridados en distintas proporciones con dichas razas, con lo cual es posible observar que mantiene características distintivas y que es diferenciable incluso de distintos grados de hibridaje presente en dicha población.

The current prevalence of asthma, allergic rhinitis, and eczema related symptoms in school-aged children in Costa Rica.

OBJECTIVE: Asthma prevalence in Costa Rica is among the highest worldwide. We aimed to determine the prevalence of asthma among school-age children in the Central Highland Area of Costa Rica. METHODS: Cross-sectional study using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was performed. Parents or guardians of children aged 6-13 years completed written questionnaires. RESULTS: Total of 2817 school-aged children returned these questionnaires (74.1% return rate). The prevalence of asthma, rhinitis, and eczema was 21.9%, 42.6%, and 19.2%, respectively. The co-existence of the 3 diseases was seen in 22.6% of children with asthma. Boys had a slightly higher prevalence of these conditions, and younger children had higher prevalence of asthma and eczema, but lower prevalence of rhinitis than older children. The use of acetaminophen and antibiotics in the first 12 months of life showed a significant association with the prevalence of asthma, rhinitis, and eczema. Wheezing with exercise, dry cough at night, and ever rhinitis was highly associated with asthma symptoms in the last 12 months. In contrast, no association was found between children exposed to smoking at home. Frequent traffic next to the house was reported more frequently by the parents of children with asthma, although no significant association was found. CONCLUSION: The prevalence of asthma showed a significant decrease compared to previous studies. However, there was an unexpected high prevalence of rhinitis. Exposure to acetaminophen and antibiotic during the first year of life was highly associated with asthma symptoms.

Physicochemical characterization of several types of naturally colored cotton fibers from Peru.

Elemental composition, physical dimensions (length and apparent diameter), and crystallinity of different types of naturally colored cotton (NCCs) fibers from Peru were investigated using a CHNS organic elemental analyzer, optical microscopy and X-Ray Diffraction (XRD). Spectroscopic studies involving Fourier Transform Infrared Spectroscopy and X-Ray photoelectron spectroscopy (XPS) were conducted; and the thermal stability of cotton samples were also investigated. Results from organic elemental analyzer and XPS showed that cotton samples contain mainly carbon, oxygen and hydrogen, but darker color samples also presented nitrogen. It was also found that the white cotton sample exhibited the longest fibers whereas the darker color samples showed the shortest values in length. Interestingly, the crystallinity seems also decrease with color intensity of NCCs. Finally, the thermal stability of white cotton fibers was similar to those obtained for the NCCs.

Cultura de seguridad y eventos adversos en una clínica de primer nivel / Culture of safety and adverse events in a first level clinic / Cultura de segurança e eventos adversos em uma clínica de primeiro nível

Objetivo: Identificar la percepción sobre clima y cultura de seguridad, y determinar la prevalencia de eventos adversos en el personal de enfermería de una clínica de primer nivel. Métodos: Estudio descriptivo, transversal y prospectivo, desarrollado en una clínica de medicina familiar del sur de la ciudad de México. Se aplicó el cuestionario Hospital survey on patient safety culture. Se utilizó estadística descriptiva. Los datos se capturaron y analizaron en el programa estadístico SPSS versión 22. Resultados: Aceptaron participar en el estudio 27 profesionales de enfermería. El promedio de edad fue de 44.7 años. Cerca del 15% refirió percibir un clima de seguridad del paciente entre excelente y muy bueno. El 66.7% del personal de enfermería describió no haber notificado ningún evento adverso. La dimensión retroalimentación y comunicación sobre errores con 75.3% aparece globalmente como fortaleza. En las debilidades percibidas, destacan 2 dimensiones: respuesta no punitiva a los errores con 61.7% y dotación de personal con 62%, ambas corresponden al área o rubro de cultura de seguridad en el nivel servicio. Conclusiones: Cerca de la tercera parte de los entrevistados no habían reportado ningún evento adverso en los últimos años, además de que solo un poco más de la mitad refirió percibir un clima de seguridad del paciente entre aceptable y superior.

Objective: To identify the perception on climate and culture of safety and prevalence of adverse events among nurses in a first level clinic. Methods: This is a descriptive, transversal and prospective study conducted in a family medicine clinic located at the south of Mexico City. The questionnaire hospital survey on patient safety culture was used. Descriptive statistics were obtained and analyzed with spss v22. Results: A total of 27 nurses agreed to participate in the study. The average age of the participants was 44.7 years old. Close to 15% said they perceive a patient safety climate between excellent and very good. The 66.7% describe having not noticed any adverse event. The dimension of feedback and communication about errors with 75.3% appears globally as a strength. In the perceived weaknesses, 2 dimensions stand out: non-punitive response to errors with 61.7% and staffing with 62% both correspond to the area or culture of service-level safety culture. Conclusions: Approximately one third of the interviewed had not reported any adverse event during the previous years, while a little more than half perceive a patient safety climate between acceptable and superior.

Objetivo: Identificar a percepção sobre clínica e cultura de segurança, e determinar a prevalência de eventos adversos em enfermeiras/os de uma clínica de primeiro nível. Métodos: Estudo descritivo, transversal e prospetivo, desenvolvido em uma clínica de medicina familiar do sul da Cidade do México. Aplicou-se o questionário hospital survey on patient safety culture: utilizou-se estatística descritiva, os dados capturaram-se e analisaram no programa estatístico spss versão 22. Resultados: Aceitaram participar no estudo vinte e sete enfermeiras/os. A média de idade foi de 44.7 anos. Cerca do 15 % refere perceber um clima de segurança do paciente entre excelente e muito bom. O 66.7% das enfermeiras/os descrevem não ter notificado nenhum evento adverso. A dimensão dos erros de feedback e comunicação com 75,3% aparece globalmente como uma fortaleza. Em debilidades percebidas, existem duas dimensões: nenhuma resposta punitiva a erros com 61,7% e de pessoal com 62%, tanto para a área ou categoria de cultura de segurança no nível de serviço. Conclusões: Cerca da terceira parte 2 entrevistados não tinham reportado algum evento adverso nos últimos anos, além disso que um pouco mais da metade refere perceber um clima de segurança do paciente entre aceitável e superior.

Morphostructural relationships and productive functionality of sheep breeds used for terminal crossbreeding in Chile / Relaciones morfoestructurales y funcionalidad productiva de razas ovinas usadas para cruzamiento terminal en Chile

The body shape of an animal population determines ranges of biological functionality and productive use. In sheep, meat productivity is closely related with the body size of the animal. Some sheep breeds are used in terminal crossbreeding to give the lamb favorable dimensional characteristics, but it is necessary to go deeper on the study of the relationships between morphostructure and productive aptitude of these breeds, since discrepancies could be due to the environmental effects or the degree of differentiation between the original pool of different breeds and the local populations. The study aimed to evaluate the morphostructural characters in four sheep breeds in Chile and discuss their relationship with the productive functionality of the body architecture. Two hundred and seventy-eight sheep belonging to Texel, Dorset, Coopworth and Suffolk Down breeds were used. Eleven body measurements (heart girth circumference, rump width, rump length, width of the cranium, length of the cranium, dorsal-sternal diameter, bicostal diameter, longitudinal diameter, cannon bone circumference, height at rump and height at withers) were taken. Nine zoometric indices (body index, cephalic index, thorax index, thorax depth index, pelvic index, longitudinal pelvic index, transverse pelvic index), metacarpal thorax index and metacarpal costal index) were composed from the individual measurements. The most important morphostructural relationships that contribute to explain the variability of the format of the four breeds of sheep studied were expressed by the metacarpal-thoracic index, the metacarpal-costal index, the thorax index and the bicostal index. Moreover, the breeds showed a high dispersion; the zoometric indices only partially explained the variability of the body format, expressing high format heterogeneity in influential variables as the metacarpal-thoracic index, the metacarpal-costal index and the body index. This could be because these racial populations are subjected to processes of differentiation within each breed.

La forma del cuerpo de una población animal determina rangos de funcionalidad biológica y su uso productivo. En las ovejas, la productividad de la carne está muy relacionada con el tamaño del cuerpo del animal. Algunas razas de ovejas se utilizan en cruzamientos terminales para dar al cordero características dimensionales favorables, pero es necesario profundizar en el estudio de las relaciones entre morfoestructura y aptitud productiva de estas razas, ya que las discrepancias podrían deberse a los efectos del medio ambiente o al grado de la diferenciación entre la piscina original de diferentes razas y las poblaciones locales. Este trabajo tuvo como objetivo evaluar los caracteres morfoestructurales en cuatro razas de ovinos en Chile y la relación de la funcionalidad productiva con la arquitectura del cuerpo. Se utilizaron 278 ovejas, raza Suffolk Down, pertenecientes a Texel, Dorset, Coopworth. Se tomaron 11 mediciones en el cuerpo (circunferencia del corazón, ancho del lomo, rabadilla, ancho del cráneo, longitud del cráneo, diámetro esternaldorsal, diámetro bicostal, diámetro longitudinal, circunferencia de hueso de la caña, altura de cadera y altura a la cruz). Nueve índices zoométricos (índice corporal, índice cefálico, índice de tórax, índice de profundidad del tórax, índice de la pelvis, índice pélvico longitudinal, índice transversal de la pelvis, índice metacarpiano del tórax e índice metacarpiano costal) fueron determinados a partir de mediciones individuales. Las relaciones morfoestructurales más importantes que contribuyen a explicar la variabilidad del formato de las cuatro razas de ovejas estudiadas se expresaron por el índice metacarpiano-torácico, el índice metacarpiano-costal, el índice de tórax y el índice bicostal. Por otra parte, las razas mostraron una alta dispersión de los índices zoométricos que explican sólo parcialmente la variabilidad del formato de cuerpo, la alto heterogeneidad de formato en las variables influyentes como el índice metacarpiano-torácica, el índice metacarpiano-costal y el índice del cuerpo. Esto podría ser debido a que estas poblaciones raciales son sometidos a procesos de diferenciación dentro de cada raza.

Variations in the vestibular cortical bone of permanent canine teeth in orthodontic patients. a comparative study: linear tomography vs. cbct (3d accuitomo).

The aim of this study was to compare the results of measuring the height of the vestibular cortical bone of canine teeth by linear tomography (LT) and 3-D Accuitomo cone beam computed tomography (CBCT) before and after aligning dental arches by orthodontic treatment. LT and CBCT were performed before and after orthodontic alignment on 12 canines in three patients undergoing orthodontic treatment, and the height of the canine vestibular cortical bones measured in mm. Measurements were taken by double-blinded operators. The mean variation in height of the vestibular cortical bone with orthodontic treatment was - 0,33 mm} 0.233 standard error using CBCT and -0,08mm } 0.55 standard error using LT. Analysis of variance (ANOVA) was performed to compare the techniques, the patients and upper and lower canines. No significant difference was found for any of the cases. Using LT to evaluate vestibular crest cortical bone in canines is comparable in efficiency to using CBCT. Height in millimeters is less in LT because image resolution is lower and when it is very thin it is not appreciable by this method.

Variations in the vestibular cortical bone of permanent canine teeth in orthodontic patients. A comparative study: linear tomography vs. CBCT 3D Accuitomo

La finalidad del presente trabajo fue comparar los resultados de la medición de la altura de la cortical vestibular de caninos, por tomografía lineal (TL) y tomografía computada de haz cónico,3D Accuitomo (CBCT, cone beam computed tomography) antes y después de alinear ortodóncicamente las arcadas dentarias. Se realizaron TL y CBCT pre y post alineación ortodóncica de 12 caninos, correspondientes a tres pacientesen tratamiento ortodóncico y se midió en mm la altura de las corticales óseas vestibulares de los caninos. Las medidasfueron tomadas por dos operadores a doble ciego. La variación de la altura promedio de la cortical vestibular con el tratamiento ortodóncico utilizando CBCT fue de -0,33 mm ± 0.233 de error standard y con TL de -0,08mm ± 0.55 de error standard. Se realizó Análisis de varianza (ANOVA) comparando las técnicas, los pacientes y los caninos superiores e inferiores, sin encontrarse diferencia estadísticamente significativa en ninguno de los casos. La evaluación de la cortical de la cresta vestibular de caninos utilizando TL es un método comparable en eficiencia a la CBCT. La medida de la altura en milímetroses menor en la TL debido a que la resolución de las imágenes es menor y no es apreciable por este método cuando ésta es extremadamente delgada...

Morphostructural differentiation and variability of Merino sheep breed under sustained directional selection / Diferenciación y variabilidad morfoestructural de ovinos de raza Merino sometidos a selección direccional sostenida

In this paper, the degree of differentiation and morphostructural variability reached by the type of animal resulting from sustained directional selection, in addition to its implications for the emergence of a new sheep breed are analyzed. Twenty-five rams and 200 ewes from a sheep flock submitted to directional selection since 1987 were measured. Thirteen body measurements were taken in other to evaluate the structural morphology and sexual dimorphism. These measurements were compared with identical measures taken in Australian Merino and Marin Magellan Meat Merino sheep breeds. The intrapopulation homogeneity was assessed using the coefficients of variation of the average percentage of body measurements. It is concluded that sustained directional selection has generated the differentiation of the morphostructural format of the subject population compared to the main Merino-type breeds in the Chilean Patagonia. The population shows a similar (and in some cases lower) morphostructural variability than those found in recognized sheep breeds in Chile, so it is possible to state that this population behaves like a different animal group, with breed characteristics.

En el presente trabajo se analiza el grado de diferenciación y variabilidad morfoestructural alcanzado por el tipo de animal resultante de una selección direccional sostenida y sus implicancias en la emergencia de un nuevo grupo racial ovino. Se midieron 25 machos y 200 ovejas adultas. Se tomaron 13 medidas corporales, evaluando la diferenciación de la morfología estructural y el dimorfismo sexual. Estas mediciones se compararon con las realizadas en animales de raza Merino Australiano y Marin Magellan Meat Merino. La homogeneidad intrapoblacional se evaluó a través de los coeficientes de variación porcentual de las medias de las medidas corporales. Se concluye que la selección direccional realizada de forma sostenida ha generado una diferenciación del formato morfoestructural al comparar a la población sujeta a selección con las principales raza de tipo Merino existentes en la Patagonia Chilena. La población evaluada evidencia una variabilidad morfoestructural similar, y en muchos casos menor a la encontrada en razas ovinas reconocidas como tales en Chile, con lo cual es posible señalar que se comporta como un grupo animal distinguible con caracteres de raza.

First Report of Root Rot of Watermelon Caused by Ceratobasidium sp. in Sonora, Mexico.

Watermelon is one of the major crops grown in Mexico and represents 4% of the total cultivated area with fruits in this country. In 2013, Sonora State was ranked second in the production of watermelon at a national level. Fungal and oomycete diseases are among the main biotic factors affecting watermelon production, particularly those caused by species of the genera Fusarium, Phytophthora, Pythium, and Rhizoctonia. During the spring of 2013, wilting or death symptoms were confirmed in approximately 50% of ungrafted watermelon plants grown in four sampled fields along the coast of Hermosillo and Guaymas Valley in Sonora, Mexico. On both roots and stems of infected plants, localized lesions were found that were 0.2 to 2.0 cm long, reddish brown, and slightly sunken on the stem base. In some cases, the discolorations encompassed nearly 90% of the root system. One-centimeter pieces from the edge of lesions on stems and roots were superficially disinfected with 1% sodium hypochlorite, then rinsed with sterile distilled water, placed onto petri dishes containing potato dextrose agar (PDA), and incubated at 25°C for 3 days. Fungal colonies were white initially, then turned brown, and septate hyphae were 3.7 to 4.3 µm in diameter and branched at right angles with a constriction at the origin of the branch point. These characteristics are typical of the genus Rhizoctonia. Binucleate cells from five isolates were observed using a lactophenol aniline blue solution stain, according to Ceratobasidium morphological descriptions. Mycelia from five isolates grown on PDA was used for DNA extraction. The rDNA-ITS region was amplified using PCR with the universal fungal primers ITS1 and ITS4 (3). The purified products were separately sequenced in both directions using the same primer pair. The sequences obtained were 99% similar to those of Ceratobasidium sp. AG-F and AG-Fa isolates (accessions KC193238.1 on Tagetes erecta, HQ168370.1 on Musa spp., and JX913821.1 on soy-rice-weeds, respectively) from GenBank (2,4). The pathogenicity of the fungus was tested under growth chamber conditions. Sets of seven healthy watermelon seedlings of the Sugar red variety were inoculated with five isolates of Ceratobasidium. Three disks (8 mm in diameter) of mycelia grown on PDA were placed around the roots of each plantlet. The pots were maintained at 27 ± 0.1°C for 14 days with a photoperiod of 12 h. Seven uninoculated seedlings were used as a control. Initial symptoms showing water-soaked lesions developed on all inoculated seedlings within 6 to 7 days, while typical disease symptoms appeared after 10 to 14 days after inoculation. Seedlings without inoculum were free from infection. The fungus was re-isolated from the inoculated seedlings on PDA, and identified as Ceratobasidium sp., confirmed using morphological characteristics. A similar disease has been reported recently in Italy and Arizona (1); however, this report is the first description of a Ceratobasidium sp. causing root rot of watermelon in Sonora, Mexico. Agricultural areas where the study was carried represent 90% of the total area cultivated with watermelon in this state, so it is necessary to evaluate the impact of this pathogen in the crop. References: (1) C. Nischwitz et al. APS joint meeting, 2013. (2) A. Saroj et al. Plant Dis. 97:1251, 2013. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990. (4) J. Yin et al. Plant Dis. 95:490, 2011.

Variations in the vestibular cortical bone of permanent canine teeth in orthodontic patients. a comparative study: linear tomography vs. cbct (3d accuitomo). / Variations in the vestibular cortical bone of permanent canine teeth in orthodontic patients. a comparative study: linear tomography vs. cbct (3d accuitomo).

The aim of this study was to compare the results of measuring the height of the vestibular cortical bone of canine teeth by linear tomography (LT) and 3-D Accuitomo cone beam computed tomography (CBCT) before and after aligning dental arches by orthodontic treatment. LT and CBCT were performed before and after orthodontic alignment on 12 canines in three patients undergoing orthodontic treatment, and the height of the canine vestibular cortical bones measured in mm. Measurements were taken by double-blinded operators. The mean variation in height of the vestibular cortical bone with orthodontic treatment was - 0,33 mmü} 0.233 standard error using CBCT and -0,08mm ü} 0.55 standard error using LT. Analysis of variance (ANOVA) was performed to compare the techniques, the patients and upper and lower canines. No significant difference was found for any of the cases. Using LT to evaluate vestibular crest cortical bone in canines is comparable in efficiency to using CBCT. Height in millimeters is less in LT because image resolution is lower and when it is very thin it is not appreciable by this method.

Intergenerational morphostructural stability and harmony of marin magellan meat merino ewes / Estabilidad y armonía intergeneracional morfoestructural de ovejas marin magellan meat merino

The aim of this study was to evaluate the stability and harmony of the morphostructural format of the Marin Magellan Meat Merino breed in order to contribute to knowledge about the differentiation of sheep populations. In summer 2010, evaluation on a sheep population coming from an incomplete absorbent crossbreeding of Corriedale by Australian Merino breeds was done in Magallanes Region, Chile. All three and five year-old ewes (62 and 50, respectively) were measured. Fourteen body measurements were taken and nine body indexes were calculated. Results show that the evaluated sheep population does not show significant intergenerational differences in most of the morphostructural variables. At the same time, there is a high between-age similarity in the correlations between zoometric indexes. Therefore, it can be stated that the morphostructural model of Marin Magellan Meat Merino ewes shows a high degree of stability and harmony.

El objetivo de este estudio fue evaluar la estabilidad y la armonía del formato morfoestructural de la raza ovina Marin Magellan Meat Merino en la Región de Magallanes (Chile), con el fin de contribuir al conocimiento de la diferenciación de las poblaciones ovinas. En el verano de 2010 se evaluó esta nueva raza, que es producto de un cruzamiento absorbente incompleto de Corriedale por Merino Australiano. Se midieron todas las hembras de tres y cinco años (62 y 50, respectivamente). Se tomaron catorce mediciones corporales y se calcularon nueve índices. Los resultados indican que la población ovina evaluada no muestra diferencias intergeneracionales significativas en la mayor parte de las variables morfoestructurales estudiadas. Al mismo tiempo, hay una gran similitud entre edades respecto a las correlaciones entre índices zoométricos. Por lo tanto, se puede afirmar que el modelo morfoestructural de las ovejas Marin Magellan Meat Merino evidencia un alto grado de estabilidad y armonía.

Biochemical characterization of ecuadorian wild Solanum lycopersicum Mill. plants produced from non-cryopreserved and cryopreserved seeds.

This paper presents some of the effects of cryopreservation of wild Solanum lycopersicum Mill. seeds on the early stages of germination post liquid nitrogen exposure. Percentage of germination, conversion into plantlets and plant fresh mass were evaluated after cryostorage. Levels of chlorophyll pigments (a, b, total), malondialdehyde, other aldehydes, phenolics (cell wall-linked, free, and total) and proteins were determined. Peroxidase and superoxide dismutase activities were recorded. Liquid nitrogen exposure increased the percentage of seed germination at 5 days but at 7 days, the conversion into plantlets and the plant fresh mass were not statistically different between non-cryopreserved and cryopreserved samples. Several significant effects of cryopreservation were recorded at the biochemical level at 7 days of germination under controlled conditions. Highly significant effects due to liquid nitrogen exposure were observed in leaves: increased levels of peroxidase enzymatic and specific activities and cell wall-linked phenolics. Very remarkable effects were also recorded in roots: decreased contents of chlorophylls and cell wall-linked phenolics.

The utility of serologic tests as biomarkers for Helicobacter pylori-associated precancerous lesions and gastric cancer varies between Latin American countries.

PURPOSE: Currently, studies on serologic diagnosis of Helicobacter pylori-associated gastric cancer (GC) in Latin America are scarce. The aim of the present study was to evaluate the association between H. pylori serology tests in patients with early precancerous lesions or GC, when compared with non-atrophic gastritis in Colombia, Paraguay, and Mexico, three countries in Latin America with a high prevalence of H. pylori infection but contrasting rates of GC mortality. METHODS: Gastric biopsies and blood samples were obtained from patients attending the gastroenterology or oncology services of hospitals in the three participating countries. IgG antibodies against H. pylori whole-cell antigens and CagA were tested in 1,117 sera using an enzyme-linked immunoabsorbent assay. RESULTS: Positive and significant associations were shown for H. pylori seropositivity and preneoplastic lesions in Mexico (OR 2.0; 95 % CI 1.1-3.4) but not in Colombia (OR 1.2; 95 % CI 0.6-2.1) or Paraguay (OR 1.5; 95 % CI 0.6-3.2); no significant associations were shown for GC in any country. CagA seropositivity was associated with preneoplasic lesions in all three countries (ORs = 2.1, 3.0, and 3.1 for Mexico, Colombia, and Paraguay, respectively), and with GC only in Colombia (OR 4.3; 95 % CI 2.1-9.2). CONCLUSIONS: In countries of Latin America, the IgG CagA test might be a useful biomarker for patients with gastric preneoplastic lesions and for those at risk of developing gastric cancer.

Intervenciones dirigidas a disminuir/evitar el sedentarismo en los escolares / Interventions Aimed to Lower/Avoid Sedentarism in Scholars

Introducción. La obesidad tiene un origen multifactorial, uno de estos factores es la inactividad física o sedentarismo, que en conjunto con otros y a largo plazo predisponen al deterioro de la salud en general, con lo que la población infantil ya está lidiando. Los hábitos activos o sedentarios adquiridos en la infancia y la adolescencia tienden a persistir en la edad adulta. Objetivo. Identificar publicaciones, en bases de datos especializadas, sobre programas de intervención que han tenido buenos resultados para disminuir o limitar el sedentarismo en escolares. Metodología. Se realizó una búsqueda en las bases de datos Medline y Redalyc de artículos publicados durante los últimos 5 años, relacionados con intervenciones enfocadas a fomentar el ejercicio físico en escolares de 6 a 12 años. Los descriptores utilizados fueron: Sedentary, childrens and sedentary, physical inactivity. De 326 artículos que arrojaron las bases de datos, se eligieron 35 por su estrecha relación con este tema. Resultados. Hay diversas razones por las que los escolares no realizan Ejercicio Físico, entre ellas está la forma de vida que los padres de familia ofrecen a sus hijos. El buen hábito de la vida activa es influenciado por el espacio y ambiente en que los niños se desarrollan. Conclusiones. Se debe prestar mayor atención a los escolares, en todas sus actividades; alimentación, tiempo que pasan fuera de casa o solos, es necesario re ubicar o reafirmar los hábitos de vida que están adquiriendo los escolares durante su desarrollo ya que los seguirán por el resto de su vida.

Introduction: Physical inactivity is one of obesity's factors, and this problem, which in the long term impairs health in general, is already found in infantile populations whose sedentary habits tend to persist through out adulthood. Objective: to address publications on successful intervention programs in lowering or limiting sedentarism in scholars. Methodology; a Medline and Redalyc database search was performed on the last five years using the key words sedentary, children, and physical inactivity. From 326 articles located, 35 were finally kept. Results: there were several reasons to explain children's inactivity including the life-style which their parents teach them, and the space or ambience in which they grow. Conclusions: More attention should be given to scholars in their activities, nutrition, and time spent at home. It is necessary to generate good life habits which children will follow for the rest of their lives.

Development of the Morphostructure and Meat Value in Chilota Lambs / Desarrollo de la Morfoestructura y el Valor Carnicero en Corderos Chilotes

Chilota sheep are typical of the Chiloé archipelago in southern Chile. The objectives of this study were: 1) To describe the development of the morphostructure of Chilota lambs in their first months of life using some variables that determine lamb meat value (zoometric traits and body weight) and 2) To determine the optimum slaughter age. Measurements were taken from 12 male single-born lambs. Body weight, Withers height; Perimeter of thorax, Chest depth, Shoulder point width and Body length were measured in each animal. The first measurements were taken at 7 days old, and the rest at 37, 67, 97, 127, 157 and 187 days old. The body weight variables and zoometric traits developed allometrically throughout the growth phase. The correlation coefficient between all the traits was very high, varying between 0.91 and 0.98. The zoometric variable that best predicted body weight was Perimeter of thorax (r2=0.93), which was fully developed in 90% of the animals at 97 days old. Maximum growth was recorded in all the studied variables during the first control month, days 7-37, but then it decreased gradually. This decrease was moderate until day 127, becoming very low from then on until end of the study. The optimum age for slaughtering fattened lambs is approximately four months, as from day 127 the daily growth rate slows down considerably, to 61.81 g/day, in comparison with the previous stage, which is 220.00 g/day. Therefore, the maintenance of lambs after four months is not productively efficient.

La oveja Chilota es una raza típica del archipiélago de Chiloé en el sur de Chile. Se midieron 12 corderos machos nacidos de parto único. En cada animal se midieronel peso corporal, la alzada a la cruz, el perímetro del tórax, diámetro dorso esternal, diámetro bicostal y la longitud corporal. Las primeras mediciones se tomaron a los 7 días de edad, y el resto a los 37, 67, 97, 127, 157 y 187 días de edad. El peso corporal y los rasgos zoométricos se desarrollaron alométricamente a lo largo de la fase de crecimiento. El coeficiente de correlaciónentre todos los rasgos fue muy elevado, variando entre 0,91 y 0,98. La variable zoométrica mejor predicha por el peso corporal fue el perímetro torácico (r2=0,93), el cual estuvo totalmente desarrollado en el 90% de los animales a los 97 días de edad. El crecimiento máximo fue registrado durante el primer mes de control (días 7-37) para todas las variables estudiadas, pero posteriormente decreció de forma gradual. Este decrecimiento fue moderado hasta el día 127, volviéndose muy lento hacia el final del estudio. La edad óptima para el sacrificio de los corderos es aproximadamente de 4 meses, dado que a partir del día 127 la tasa diaria de crecimiento disminuye considerablemente, a 61,81 g/día, en comparación con la etapa previa, donde esta tasa es de 220,00 g/día.Por lo tanto, el sacrificio de los corderos más allá de los 4 meses de edad no resulta productivamente eficiente.

Phytoremediation and removal mechanisms in Bouteloua curtipendula growing in sterile hydrocarbon spiked cultures.

Tolerance index and phytoremediation factors of side oats grama (Bouteloua curtipendula) with recalcitrant polycyclic aromatic hydrocarbons (PAH) phenanthrene (PHE), pyrene (PYR), and benzo[a]pyrene (BaP) and the resulting impact on phenotypic response, were evaluated in sterile conditions with whole plant growing in test-tube cultures with MS medium with PAH and compared with Tall fescue (Festuca arundinacea), control for this study. PAH mixture of PHE, PYR and BaP (1:1:1 w/w/w) blended with Maya crude oil (1:1 w/w), final concentration of 1500 mg kg(-1) was used. After 40 days, BaP removal, in the presence of Maya crude was superior compared with PHE and PYR removal Although the presence of PAH negatively affects the phenotypic response of the plants; sterile conditions experiments were helpful to evaluate phytoremediation factors to elucidate some important questions regarding phytoremediation mechanisms; in this study, B. curtipendula was able to phytostabilizate BaP associated to a significant hydrocarbon removal (57.4%) with high root accumulation but attenuated transport to stems, here reported as translocation factor. To our knowledge, this is the first time that quantifiable phytoremediation factors were used to evaluate the tolerance and removal capacity of a native semi-arid climate plant which is probably able to phytoremediate hydrocarbon contaminated soils.

Morphology differentiation and structural functionality of ewes due to incomplete crossbreeding / Diferenciación morfológica y funcionalidad estructural de ovejas debido a cruzamiento incompleto

Most Chilean sheep stock comprises different degrees of crossbreeding over Corriedale breed. A common absorbent crossbreeding has been Australian Merino over Corriedale which, in many cases, has not been complete. The aim of this study was to evaluate the process of morphology differentiation and structural functionality of Corriedale ewes undergoing incomplete absorbent crossbreeding which was carried out in order to create an animal with a new morphology. A total of four hundred adult ewes were measured; two hundred belonging to the incomplete crossbreeding, and two hundred from the two original breeds (one hundred Corriedale and one hundred Australian Merino ewes). All measured ewes were randomly selected. Fourteen body measurements were recorded and nine body indexes were calculated for each ewe. Results show that a new biotype has been created from the absorbent crossbreeding of Corriedale by Australian Merino, which produced ewes with a clear morphological and structural functionality differentiation as compared to the two original breeds. The new body format shows morphostructural variability coefficients that are similar to those found on other formally recognized sheep breeds.

La mayor parte del stock ovino chileno comprende diferentes grados de cruzamiento con la raza Corriedale. Un cruzamiento absorbente común ha sido el de Merino Australiano sobre Corriedale, el cual, en muchos casos, no ha sido completo. En este estudio se evaluó el proceso de diferenciación morfológica y funcionalidad estructural de las ovejas Corriedale que fueron previamente sometidas a cruzamiento absorbente incompleto con el fin de crear un animal con una nueva morfología. Se midió un total de cuatrocientas ovejas adultas, doscientas provenientes del cruzamiento incompleto y doscientas de las dos razas originales (cien ejemplares de raza Corriedale y cien de Merino australiano). Todas las ovejas medidas fueron seleccionadas al azar. Para cada animal se registraron catorce mediciones corporales y se calcularon nueve índices. Los resultados de los análisis permiten concluir que el cruzamiento absorbente de Corriedale por Merino Australiano ha generado un nuevo biotipo ovino, con una diferenciación morfológica clara y diferente funcionalidad estructural al ser comparadas con las dos razas originales. Los coeficientes de variabilidad morfoestructural que presenta el nuevo formato corporal fueron similares a los de otras razas ovinas formalmente reconocidas.

Inmunodetección de metaloproteinasas de matriz extracelular (MMPs)-2, -9, -13 y -14 en lesiones apicales asociadas con periodontitis apical asintomática / Immunodetection of matrix metalloproteinases (MMPs)-2, -9, -13 and -14 in periapical lesions associated with asymptomatic apical periodontitis

La periodontitis apical asintomática (PAa) es una patología infecciosa caracterizada por destrucción ósea perirradicular asociada a un proceso inflamatorio crónico y producción de mediadores inflamatorios, entre los cuales se encuentran las metaloproteinasas de matriz extracelular (MMPs). Entre éstas, las MMPs-13, -14, -2 y -9, son producidas por el tejido óseo y degradan sinérgicamente el colágeno tipo I, principal componente de los tejidos periodontales, y gelatina, producto de la degradación y desnaturación del colágeno. El objetivo de este estudio fue determinar el patrón de expresión de las MMPs-2, -9, -13 y -14 en granulomas periapicales (GPAs), quistes radiculares inflamatorios (QRIs) y ligamento periodontal sano (LS). Materiales y Métodos: Se seleccionaron 12 pacientes con diagnóstico clínico de PAa e indicación de exodoncia a partir de los cuales se obtuvieron biopsias de lesiones periapicales (LPAs). Como controles, se seleccionaron 7 individuos con indicación de exodoncia de premolares por ortodoncia, obteniéndose biopsias de LS. Se efectuó el diagnóstico anátomo-patológico de los especímenes y se caracterizó la expresión de las MMPs en estudio mediante inmunohistoquímica. Resultados: Las MMPs en estudio sólo se detectaron en GPAs y QRIs, y se inmunolocalizaron principalmente en el infiltrado inflamatorio de éstos. Adicionalmente, la MMP-2 se identificó en fibroblastos del tejido conectivo. Conclusiones: MMPs-2, -9, -13 y -14 se expresan predominantemente en el infiltrado inflamatorio de las LPAs y no en LS, y por tanto se sugiere la participación de estos mediadores en la patogénesis de la PAa.

Asymptomatic apical periodontitis (aAP) is an infectious disease characterized by perirradicular bone destruction associated with chronic inflammation and release of inflammatory mediators, such as matrix metalloproteinases (MMPs). MMPs-13, -14 and -2, -9 are bone-expressed enzymes that can synergistically degrade collagen I, the main component of periodontal extracellular matrix, and gelatin, the product of degradation and denaturation of collagen. The aim of this study was to characterize the expression pattern of MMPs-2, -9, -13, and -14 in periapical granulomas (PGs), radicular cysts (RCs) and healthy periodontal ligament (PDL). Materials and Methods: Individuals with clinical diagnosis of aAP and indication of extraction were selected (N=12), and biopsies of periapical lesions (PLs) were obtained. For controls, 7 subjects with indication of premolar extraction for orthodontic reasons were selected, and PDL biopsies were obtained. Samples were diagnosed by anatomopathological examination and immunohistochemical staining was carried out to characterize MMPs expression. Results: MMPs-2, -9, -13 and -14 detection was limited to PLs and were localized mainly to inflammatory infiltrate on both, PGs and RCs. Additionally, MMP-2 was immunolocalized to fibroblasts from the connective tissue. Conclusions: Whereas MMPs-2, -9, -13 and -14 were not detected in healthy periodontal ligament, they were highly expressed on inflammatory infiltrate from PGs and RCs, suggesting a role of these mediators in aAP pathogenesis.