Yield of white clover and orchard grass cultivated in mining passives adding black earth and compost as a substrate.

Mining environmental liabilities generate environmental pollution. The objective of the present study was to determine the yield of white clover (Trifolium repens) and orchard grass (Dactylis glomerata) cultivated in mining environmental passives adding black earth and compost as a substrate in the Buenaventura Julcani Huancavelica Company. The treatments were the combinations: 4: 3.1: 3.1: 3:1.1 kg of RP: RP, TN: RP, C: RP, TN, C respectively. They were distributed in four treatments with twelve experimental units for each species of leguminous and gramineous grass, we worked according to the completely randomized design (DCA) with a 2 x 4 factorial arrangement, the experimental unit being a treatment with twelve repetitions. The variables evaluated were: germination percentage (TG) and stem survival percentage (TST). For the statistical analysis, the SPSS software was used.

Characterization of the trypsin-III from Monterey sardine (Sardinops caeruleus): Insights on the cold-adaptation from the A236N mutant.

Trypsins (E.C. 3.4.21.4) are digestive enzymes that catalyze the hydrolysis of peptide bonds containing arginine and lysine residues. Some trypsins from fish species are active at temperatures just above freezing, and for that are called cold-adapted enzymes, having many biotechnological applications. In this work, we characterized a recombinant trypsin-III from Monterey sardine (Sardinops caeruleus) and studied the role of a single residue on its cold-adapted features. The A236N mutant from sardine trypsin-III showed higher activation energy for the enzyme-catalyzed reaction, it was more active at higher temperatures, and exhibited a higher thermal stability than the wild-type enzyme, suggesting a key role of this residue. The thermodynamic activation parameters revealed an increase in the activation enthalpy for the A236N mutant, suggesting the existence of more intramolecular contacts during the activation step. Molecular models for both enzymes suggest that a hydrogen-bond involving N236 may contact the C-terminal α-helix to the vicinity of the active site, thus affecting the biochemical and thermodynamic properties of the enzyme.

Refolding and Activation from Bacterial Inclusion Bodies of Trypsin I from Sardine (Sardinops sagax caerulea).

BACKGROUND: Trypsin from fish species is considered as a cold-adapted enzyme that may find potential biotechnological applications. In this work, the recombinant expression, refolding and activation of Trypsin I (TryI) from Monterey sardine (Sardinops sagax caerulea) are reported. METHODS: TryI was overexpressed in Escherichia coli BL21 as a fusion protein of trypsinogen with thioredoxin. Refolding of trypsinogen I was achieved by dialysis of bacterial inclusion bodies with a recovery of 16.32 mg per liter of Luria broth medium. RESULTS: Before activation, the trypsinogen fusion protein did not show trypsin activity. Trypsinogen I was activated by adding 0.002 U of native TryI purified from the sardine pyloric caeca (nonrecombinant). The activated recombinant trypsin showed three times more activity than the nonrecombinant trypsin alone. CONCLUSION: The described protocol allowed obtaining sufficient amounts of recombinant TryI from Monterey sardine fish for further biochemical and biophysical characterization of its coldadaptation parameters.

White shrimp Litopenaeus vannamei recombinant lactate dehydrogenase: Biochemical and kinetic characterization.

Shrimp lactate dehydrogenase (LDH) is induced in response to environmental hypoxia. Two protein subunits deduced from different transcripts of the LDH gene from the shrimp Litopenaeus vannamei (LDHvan-1 and LDHvan-2) were identified. These subunits are expressed by alternative splicing. Since both subunits are expressed in most tissues, the purification of the enzyme from the shrimp will likely produce hetero LDH containing both subunits. Therefore, the aim of this study was to overexpress, purify and characterize only one subunit as a recombinant protein, the LDHvan-2. For this, the cDNA from muscle was cloned and overexpressed in E. coli as a fusion protein containing an intein and a chitin binding protein domain (CBD). The recombinant protein was purified by chitin affinity chromatography column that retained the CBD and released solely the full and active LDH. The active protein appears to be a tetramer with molecular mass of approximately 140 kDa and can use pyruvate or lactate as substrates, but has higher specific activity with pyruvate. The enzyme is stable between pH 7.0 to 8.5, and between 20 and 50 °C with an optimal temperature of 50 °C. Two pKa of 9.3 and 6.6, and activation energy of 44.8 kJ/mol°K were found. The kinetic constants Km for NADH was 23.4 ± 1.8 µM, and for pyruvate was 203 ± 25 µM, while Vmax was 7.45 µmol/min/mg protein. The shrimp LDH that is mainly expressed in shrimp muscle preferentially converts pyruvate to lactate and is an important enzyme for the response to hypoxia.

Prevalence of temporomandibular joint disorders in a mexican elderly group / Prevalencia de trastornos temporomandibulares en un grupo de adultos mayores mexicanos

Abstract: Aim: to determine frequency and distribution of temporomandibulardisorders (TMD) by age and sex in a group of elderly adults in Mexico City. Material and methods: One hundred and fifty-four older adults in Mexico City were examined in a cross-sectional study. Subjects who had big edentulous gaps (absence of two or more teeth) or those who were fully edentulous, as well as those who refused to participate, were excluded from the study. For the epidemiological survey, diagnostic criteria for Temporomandibular Disorders (DC/TMD), after standardization by a dentist (kappa=0.892), were considered. Results. A 33.1 percent had some type of TMD, being more common in people between 60 and 69 years old, variable with which it was related (Likelihood Ratio=21.553, p=0.006, X2 MH=08.389, p=0.021). A 14.3 percent reported some type of facial trauma history, behavior that also was statistically significant (X2 MH=13.566, p= 0.0001). Disorders that occurred most frequently were: disc displacement with reduction (62.8 percent) and disc displacement without reduction (9.8 percent). Conclusions. TMD occurred in one of every three subjects examined, showing a relationship with age and trauma history.

Resumen: Objetivo. determinar la frecuencia y distribución de los trastornos temporomandibulares (TTM) por edad y sexo en un grupo de adultos mayores de la Ciudad de México. Material y métodos. Estudio de corte transversal. Se examinaron 154 adultos mayores de la Ciudad de México. Fueron excluidos del estudio a todos aquellos que presentaron brechas edéntulas amplias (ausencia de dos ó más dientes) o edentulismo total, así como aquellos que no aceptaron participar en el estudio. Para la encuesta epidemiológica se tomaron en cuenta los Criterios Diagnósticos de los Trastornos Temporomandibulares (CD/TTM), previa estandarización de una Cirujana Dentista (kappa=0.892). Resultados. El 33.1 por ciento presentó algún tipo de TTM, siendo más frecuente en personas entre 60 y 69 años variable con la cual estuvo relacionada (Razón de verosimilitud=21,553, p=0,006, X2 MH=08,389, p=0,021). El 14,3 por ciento refirió algún tipo de antecedente traumático facial, comportamiento que también resultó ser estadísticamente significativo (X2 MH=13,566, p=0,0001). Los trastornos que se presentaron con mayor frecuencia fueron: el desplazamiento del disco con reducción (62,8 por ciento) y el desplazamiento del disco sin reducción (9,8 por ciento). Conclusiones. Los TTM se presentaron en uno de cada tres adultos mayores examinados, existiendo una relación con la edad y los antecedentes traumáticos.

Prospective randomized controlled study comparing low-cost LED and conventional phototherapy for treatment of neonatal hyperbilirubinemia.

Our objective was to carry out a prospective, randomized, single-blind study to evaluate whether light emitting diode (LED) phototherapy using a low-cost set of lights is as effective as conventional phototherapy in treating hyperbilirubinemia in neonates. The study included 45 pre-term neonates requiring phototherapy as per American Academy of Pediatrics guidelines; participants were randomized to receive phototherapy using LED-based lights, conventional fluorescent blue lights or conventional halogen lights. There were no statistically significant differences in the average bilirubin levels at the onset, at the maximum and at the end of treatment, nor in the duration of phototherapy treatment and the rate of decrease in bilirubin levels in the neonates receiving conventional fluorescent blue light, conventional halogen light and LED phototherapy. (Differences were considered significant at p < 0.05). The average rate of decrease of bilirubin levels was 0.047 ± 0.037 mg dl(-1) h(-1), 0.055 ± 0.056 mg dl(-1) h(-1) and 0.057 ± 0.045 mg dl(-1) h(-1) in the groups receiving conventional fluorescent blue light, conventional halogen light and LED phototherapy, respectively. The average duration of phototherapy treatment in the three groups was 108.8 ± 85.9 h, 92.8 ± 38.1 h, 110.4 ± 42.6 h, respectively. In this pilot study, LED phototherapy using a simple, low-cost set of lights was as effective as conventional phototherapy in the treatment of neonatal hyperbilirubinemia. LED phototherapy lights that deliver 30-40 µW cm(-2 )nm(-1) can be assembled in small quantities for

Correlaciones fenotípicas entre características productivas en alpacas Huacaya / Phenotypic correlations between production characteristics in the Huacaya alpaca

El presente estudio tuvo como objetivo determinar correlaciones fenotípicas entre peso corporal de la alpaca a la esquila (PCE), peso de vellón sucio (PVS), peso de vellón limpio (PVL), rendimiento de la fibra al lavado (RFL), diámetro medio de las fibras (DMF), longitud de fibra (LF), número de rizos (NR), incidencia de fibras meduladas (IM), peso corporal de la alpaca al parto (PCP) y peso de la cría al nacimiento (PCC). Se trabajó con 185 alpacas Huacaya, blancas, de 1 a 7 años de edad, del Centro Experimental de Camélidos Sudamericanos Lachocc de la Universidad Nacional de Huancavelica, durante los años 2007 y 2008. Las correlaciones fenotípicas fueron: PVS-PVL = 0.99, PVS-LF = 0.55, PVS-DMF = 0.52, PVS-PCE = 0.41, PVL-LF = 0.57, PVL-DMF = 0.54, PVL-PCE = 0.43 (p<0.01). El peso de vellón no presentó antagonismo con las principales características relacionadas a la producción de fibra, y por la alta interrelación entre el peso de vellón sucio y el diámetro de fibra se puede usar como criterio de selección en un programa de mejoramiento genético que esté orientado a la producción de fibra.

The aim of the present study was to determine phenotypic correlations between body weight of the alpaca at shearing (PCE), greasy fleece weight (PVS), clean fleece weight (PVL), performance of the fibre Andalusia wash (RFL), mean diameter of the fibre (DMF), fibre length (LF), number of loops (NR), incidence of spinal cord fibres (IM), body weight at parturition (PCP) and body weight of calf at birth (PCC). The study considered 185 white Huacaya alpacas, 1 to 7 years old, from the Lachocc Experimental Center of South American Camelids, Universidad Nacional de Huancavelica, in 2007 and 2008. The phenotypic correlations were: PVS-PVL = 0.99, PVS-LF = 0.55, PVS-DMF = 0.52, PVS-PCE = 0.41, PVL-LF = 0.57, PVL-DMF = 0.54, PVL-PCE = 0.43 (p<0.01). Fleece weight does not show any interference with main characteristics related to fibre production, and due to the high interrelation between dirty fleece weight and diameter of fibre, it can beused as a valid criterion for selection in a genetic improvement programme aimed at fibre production.

Análisis de las causas de ausentismo injustificado con un grupo focal de enfermeras / Causes of unjustified absence analysis with a focal group of nurses

Introducción: El ausentismo laboral es una interacción de diversos factores y de distintas fuerzas que interactúan entre sí, por ello es considerado una medida muy cercana al grado de bienestar alcanzado por una persona, tanto en el área laboral como en la personal. Ha sido analizado desde otras perspectivas, pero no a través de grupos focales. Objetivo: Explorar e identificar las percepciones de las enfermeras sobre las causas de ausentismo injustificado en un grupo de discusión. Metodología: Se integró un grupo de discusión con cinco enfermeras que presentaron ausentismo injustificado. En una sesión de dos horas y con base en una guía se disertó sobre las causas de ausentismo (doble empleo, trabajador foráneo, responsabilidad familiar, relaciones interpersonales y motivación para con la institución y profesión). Resultados: Las puntos de vista expresados como causas de ausentismo fueron, el autoritarismo de los directivos, el clima laboral adverso, la atención a familiar enfermo y otro empleo mejor remunerado. Conclusiones: La principal causa de ausentismo manifestada en el grupo focal, fue el ambiente laboral adverso y maltrato por parte del jefe inmediato. En este sentido, se deben buscar alternativas para mejorar el clima laboral en que el personal se desempeña e incidir en el ausentismo generado por esta causa.

Introduction: Absence from work is an interaction of different factors and forces that interact each other; so that, it is considered as a close grade of well-being that is achieved by a person in both, working and personal areas. It has been analyzed from other perspectives, but not through focal groups. Objective: To explore and identify the perceptions of nurses about the causes of unjustified absence in a group of discussion. Methodology: A discussion group of five nurses who had unjustified absence was integrated. During a two hours session and over the base of a guideline, causes of absence were discussed (double employment, foreign worker, family responsibility, interpersonal relationships, and professional or institutional motivation). Results: The expressed points of view as causes of absence were, managers over authorities, adverse working dimate, assistance to an ill family member, and another better paid employment. Conclusions: The main cause of absence manifested in the focal group was the adverse working environment and mistreat from immediate boss. In this sense, it is necessary to look for alternatives to improve the working environment where the staff works, and diminish the absence rate generated for this reason.

Sexo seguro entre adolescentes / Safe sex among adolescents

Introducción: los cambios en el estilo de vida tradicional de los adolescentes, influenciados por la excesiva información recibida respecto al inicio temprano de la actividad sexual les generan un mayor riesgo para adquirir enfermedades de transmisión sexual; por tanto, el objetivo de este estudio es establecer los factores relacionados con la adopción de medidas para la práctica del sexo seguro entre adolescentes de 15 a 19 años de edad. Material y métodos: estudio transversal descriptivo a 83 adolescentes de ambos géneros, de 15 a 19años de edad, con vida sexual activa y adscritos a la Unidad de Medicina Familiar N° 57 del Instituto Mexicano del Seguro Social quienes fueron divididos en dos grupos: el primero con 47 jóvenes que usaron condón durante las relaciones sexuales (sexo seguro) y el segundo grupo con 36 adolescentes que no lo utilizaron, las variables se analizaron con X2 y razón de momios, cuando se obtuvo significancia. Resultados: se detectó uso de condón en la primera y última relación sexual, así como método de planificación familiar los cuales se relacionan con la práctica del sexo seguro. Discusión: los resultados difieren de otros estudios en una proporción mayor, respecto a la adopción de sexo seguro y a la edad de inicio de las relaciones sexuales. El uso de condón, durante la primera relación sexual, favorece que los adolescentes continúen utilizándolo en forma posterior.

Objective: to establish the factors associated with taking up the safe sex among teenagers of 15-19 years old at the responsability area of the Family Medicine Unit number 57. Material and methods: transversal, comparativa study in 83 teenagers with both sex, of 15-19 years with sexual activity. They were divided in 2 groups: group A with 47 teenagers who use condom during their sexual relations (safe sex) and group B with 36 teenagers who no use it, the variables were analyzed by X2 and with odds ratio when were significativa. Results: this study showed that the use of condom in their first sexual experience, in their last sexual experience and the use of a family planification method were relationed with taking up of safe sex, and the other variables no have relation. Conclusions: taking up the safe sex of condom during the first sexual experience favors its use in future events among teenagers.