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Neoscytalidium dimidiatum is a plant pathogen, but can also cause onychomycosis. We compared clinical and epidemiological data of cases of onychomycosis caused by N. dimidiatum and Trichophyton rubrum. We also evaluated the in vitro antifungal susceptibility of N. dimidiatum clinical isolates. It was not possible to establish any statistical differences between groups, except the place of residence and the number of affected nails. The results suggest that onychomycosis caused by N. dimidiatum is clinically similar to that caused by T. rubrum; besides, N. dimidiatum has been shown to have low sensitivity to itraconazole, but high to terbinafine. LAY SUMMARY: Cases of onychomycosis caused by Neoscytalidium dimidiatum were studied and compared to cases of onychomycosis caused by T. rubrum. The individuals affected were adults, and the clinical characteristics were not different between groups; accordingly, mycological diagnosis is mandatory.
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Identification of filamentous fungi by conventional phenotypic methods are time-consuming, and a correct identification at the species level is prone to errors. Therefore, a more accurate and faster time-to-results, and cost-effective technique, is required, such as the Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). In this study, we describe the development of an in-house spectra library for the identification of filamentous fungi frequently isolated from patients with infections. An in-house spectra library was constructed using 14 reference strains grown in solid medium. Clinical isolates were identified either by the in-house spectra library or the Biotyper commercial library from Bruker Daltonics. Fungal identification was carried following the Biotyper's established scores: ≤1.699: not reliably identified (NRI); 1.700-1.999: genus-level; ≥2.000: species-level. Clinical isolates were identified, with the in-house library, at species- and genus-level at 88.70% (55) and 3.22% (2), respectively. While 4.80% (3) was NRI and 3.22% (2) was discrepant concerning sequencing. On the contrary, identification up to species and genus-level with the commercial library was 44.44% (16) and 22.22% (8), respectively. NRI and the discrepancy was 30.55% (11) and 2.77% (1), respectively. For the reaming 26 isolates, 16 from Neoscytalidium dimidiatum and 10 from Sporothrix spp., respectively, the absence of spectrum and the specific spectra within the Sporothrix complex in the commercial library resulted in the inability to obtain an identification. In conclusion, the current results advocate the importance that each clinical microbiological laboratory needs to develop an ad hoc library associated with the MALDI-TOF MS fungal identification to overcome the limitations of the available commercial libraries.
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Within the Neoscytalidium genus, N. dimidiatum, N. oculus, N. orchidacearum, and N. novaehollandiae have been recognized. Although these species are frequently found in soil, N. dimidiatum has been identified as an etiologic agent of onychomycosis or dermatomycosis, and N. oculus has been identified as an etiologic agent of an ocular lesion. All these species can be cultured in vitro, but their morphological identification by macroscopic and microscopic traits is difficult and imprecise due to their similarity. In this study, 34 isolates of Neoscytalidium spp. from 32 onychomycosis and two dermatomycosis cases in Medellin (Colombia) were identified at the species level using sequencing of the ITS1+5.8S+ITS2 nuclear rDNA region and MALDI-TOF mass spectrometry (MS). Neoscytalidium dimidiatum strain MUM 17.21 was used to construct the reference spectrum in the in-house library to identify the clinical isolates by MALDI-TOF MS. Additionally, N. dimidiatum PPC-216 and PLAB-055 strains were used to validate the in-house constructed reference spectra. Although four groups were observed in the dendrogram obtained from the proteins of each isolate profile, MALDI-TOF MS and sequencing results are in accordance, since all isolates were identified as N. dimidiatum.
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Human epidemiological and animal-model studies suggest that separate exposure to stress or serotonin-selective reuptake inhibitor (SSRI) antidepressants during pregnancy increases risks for neurodevelopmental disorders in offspring. Yet, little is known about the combined effects of maternal stress and SSRIs with regard to brain development in utero. We found that the placenta is highly permeable to the commonly prescribed SSRI (±)-citalopram (CIT) in humans and mice, allowing rapid exposure of the fetal brain to this drug. We investigated the effects of maternal chronic unpredictable stress in mice with or without maternal oral administration of CIT from embryonic day (E)8 to E17. We assessed fetal brain development using magnetic resonance imaging and quantified changes in serotonergic, thalamocortical, and cortical development. In utero exposure to maternal stress did not affect overall fetal brain growth. However, serotonin tissue content in the fetal forebrain was increased in association with maternal stress; this increase was reversed by maternal CIT. In utero exposure to stress increased the numbers of deep-layer neurons in specific cortical regions, whereas CIT increased overall cell numbers without changing the proportions of layer-specific neurons to offset the effects of stress on deep-layer cortical development. These findings suggest that stress and SSRI exposure in utero differentially impact serotonin-dependent fetal neurodevelopment such that CIT reverses key effects of maternal gestational stress on offspring brain development.
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Encéfalo/efectos de los fármacos , Citalopram/farmacología , Desarrollo Fetal/efectos de los fármacos , Exposición Materna , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Estrés Psicológico , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Femenino , Desarrollo Fetal/fisiología , Imagen por Resonancia Magnética , Ratones , Neurogénesis/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Embarazo , Serotonina/metabolismoRESUMEN
We report two cases of acute aseptic meningitis associated to mumps in middle-aged women, one pregnant. Both presented shortly after parotid gland enlargement. Neurological complications were suspected by headache, fever and meningeal signs and confirmed by CSF findings (mononuclear predominant pleocytosis) with negative results for alternative causes. Mumps were confirmed by positive IgM and IgG serology. Both patients were discharged with a favorable evolution and complete disappearance of symptoms. Cases were concurrent with a regional mumps outbreak. Conclusions: Aseptic meningitis is a rare mumps-associated neurological complication. Its diagnostic can be achieved by precedent parotid enlargement, mononuclear pleocytosis in the CSF and positive IgM and IgG serology or viral detection by PCR in urine or salivary samples. This complication would be more probably observed during mumps outbreaks.
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Meningitis Aséptica/virología , Paperas/complicaciones , Adulto , Distribución por Edad , Chile/epidemiología , Epidemias , Femenino , Humanos , Incidencia , Meningitis Aséptica/epidemiología , Meningitis Aséptica/patología , Paperas/epidemiología , Paperas/patología , Factores de Riesgo , Estaciones del Año , Factores de TiempoRESUMEN
Resumen Comunicamos dos casos de meningitis aséptica asociadas a parotiditis viral en mujeres de edad mediana, una de ellas embarazada. Ambas se presentaron pocos días después del aumento de volumen parotídeo, con cefalea, fiebre y signos meníngeos, pleocitosis de predominio mononuclear en el LCR y resultados negativos para otras causas. La parotiditis fue confirmada por serología IgG e IgM positiva. Las pacientes tuvieron una evolución favorable con desaparición total de sus síntomas. Ambos casos ocurrieron durante un brote regional de parotiditis. La meningitis aséptica es una complicación frecuente de las parotiditis. Su diagnóstico puede lograrse por el aumento de volumen glandular precedente, la pleocitosis de predominio mononuclear en el LCR y una serología IgM e IgG positiva o detección genómica por RPC en muestra urinaria o salival. Esta complicación es más probable que sea observada durante brotes de parotiditis viral.
We report two cases of acute aseptic meningitis associated to mumps in middle-aged women, one pregnant. Both presented shortly after parotid gland enlargement. Neurological complications were suspected by headache, fever and meningeal signs and confirmed by CSF findings (mononuclear predominant pleocytosis) with negative results for alternative causes. Mumps were confirmed by positive IgM and IgG serology. Both patients were discharged with a favorable evolution and complete disappearance of symptoms. Cases were concurrent with a regional mumps outbreak. Conclusions: Aseptic meningitis is a rare mumps-associated neurological complication. Its diagnostic can be achieved by precedent parotid enlargement, mononuclear pleocytosis in the CSF and positive IgM and IgG serology or viral detection by PCR in urine or salivary samples. This complication would be more probably observed during mumps outbreaks.
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Humanos , Femenino , Adulto , Meningitis Aséptica/virología , Paperas/complicaciones , Estaciones del Año , Factores de Tiempo , Chile/epidemiología , Incidencia , Factores de Riesgo , Distribución por Edad , Epidemias , Meningitis Aséptica/patología , Meningitis Aséptica/epidemiología , Paperas/epidemiologíaRESUMEN
Fetal exposure to selective serotonin reuptake inhibitors (SSRI) has been associated with increased risk of adverse neurodevelopmental outcomes. In the adult brain, SSRI therapy regulates p11 (s100a10) expression and alters neurogenesis. The protein p11 indirectly regulates 5-HT signaling through 5-HT1B/D receptors. In the fetal brain, signaling through these receptors modulates axonal circuit formation. We determined whether p11 is expressed in the fetal mouse brain, and whether maternal SSRI exposure affects fetal p11 expression and neurogenesis. The SSRI ± citalopram was administered to pregnant mice from gestational day 8 to 17. Results show that p11 is expressed in fetal thalamic neurons and thalamocortical axons. Furthermore, p11 protein expression is significantly decreased in the fetal thalamus after in utero ±citalopram exposure compared to untreated controls, and neurogenesis is significantly decreased in specific fetal brain regions. These findings reveal differential regulation of p11 expression and altered neurogenesis in the fetal brain as a result of maternal SSRI exposure.
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Citalopram/farmacología , Neurogénesis/efectos de los fármacos , Neuronas/efectos de los fármacos , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Tálamo/efectos de los fármacos , Animales , Axones/efectos de los fármacos , Femenino , Exposición Materna , Ratones , EmbarazoRESUMEN
The genomic island 9 (SPI-9) from Salmonella enterica serovar Typhi (S. Typhi) carries three ORFs (STY2876, STY2877, STY2878) presenting 98 % identity with a type 1 secretory apparatus (T1SS), and a single ORF (STY2875) similar to a large RTX-like protein exhibiting repeated Ig domains. BapA, the Salmonella enterica serovar Enteritidis orthologous to S. Typhi STY2875, has been associated with biofilm formation, and is described as a virulence factor in mice. Preliminary in silico analyses revealed that S. Typhi STY2875 ORF has a 600 bp deletion compared with S. Enteritidis bapA, suggesting that S. Typhi STY2875 might be non-functional. At present, SPI-9 has not been studied in S. Typhi. We found that the genes constituting SPI-9 are arranged in an operon whose promoter was up-regulated in high osmolarity and low pH in a RpoS-dependent manner. All the proteins encoded by S. Typhi SPI-9 were located at the membrane fraction, consistent with their putative role as T1SS. Furthermore, SPI-9 contributed to adherence of S. Typhi to epithelial cells when bacteria were grown under high osmolarity or low pH. Under the test conditions, S. Typhi SPI-9 did not participate in biofilm formation. SPI-9 is functional in S. Typhi and encodes an adhesin induced under conditions normally found in the intestine, such as high osmolarity. Hence, this is an example of a locus that might be designated a pseudogene by computational approaches but not by direct biological assays.
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Adhesión Bacteriana/genética , Proteínas Bacterianas/genética , Células Epiteliales/microbiología , Islas Genómicas/genética , Salmonella typhi/genética , Salmonella typhi/patogenicidad , Factor sigma/genética , Sistemas de Secreción Tipo I/genética , Adhesinas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Células CACO-2 , Línea Celular Tumoral , Escherichia coli/genética , Humanos , Salmonella enteritidis/genética , Salmonella enteritidis/patogenicidad , Factores de Virulencia/genéticaRESUMEN
While selective-serotonin reuptake inhibitor (SSRI) antidepressants are commonly prescribed in the treatment of depression, their use during pregnancy leads to fetal drug exposures. According to recent reports, such exposures could affect fetal development and long-term offspring health. A central question is how pregnancy-induced physical and physiological changes in mothers, fetuses, and the placenta influence fetal SSRI exposures during gestation. In this study, we examined the effects of gestational stage on the maternal pharmacokinetics and fetal disposition of the SSRI (±)-citalopram (CIT) in a mouse model. We determined the maternal and fetal CIT serum concentration-time profiles following acute maternal administration on gestational days (GD)14 and GD18, as well as the fetal brain drug disposition. The results show that pregnancy affects the pharmacokinetics of CIT and that maternal drug clearance increases as gestation progresses. The data further show that CIT and its primary metabolite desmethylcitalopram (DCIT) readily cross the placenta into the fetal compartment, and fetal exposure to CIT exceeds that of the mother during gestation 2 h after maternal administration. Enzymatic activity assays revealed that fetal drug metabolic capacity develops in late gestation, resulting in elevated circulating and brain concentrations of DCIT at embryonic day (E)18. Fetal exposure to the SSRI CIT in murine pregnancy is therefore influenced by both maternal gestational stage and embryonic development, suggesting potential time-dependent effects on fetal brain development.
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Citalopram/farmacocinética , Feto/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal , Inhibidores Selectivos de la Recaptación de Serotonina/farmacocinética , Animales , Cromatografía Líquida de Alta Presión , Citalopram/toxicidad , Femenino , Ratones , Embarazo , Inhibidores Selectivos de la Recaptación de Serotonina/toxicidadRESUMEN
Introducción: La frecuencia cardíaca es un indicador que se usa con frecuencia para la estimación del consumo de oxígeno. Ha sido empleado para evaluar la carga física global sin embargo su uso para evaluar el trabajo que no involucra todo el cuerpo no ha sido lo suficientemente comprobado. Objetivo: Determinar la relación entre el consumo de oxígeno por segmentos corporales y la frecuencia cardíaca. Métodos: Se estableció la relación entre frecuencia cardíaca, el consumo de oxígeno y el porcentaje de consumo máximo de oxígeno mediante ergoespirometria y pulsometría en 30 individuos expuestos a cargas máximas ejecutadas con todo el cuerpo, miembros inferiores y miembros superiores. Resultados: Se encontraron diferencias estadísticamente significativas entre el consumo de máximo oxígeno por género y por segmentos corporales. No hubo diferencias representativas entre las proporciones de consumo de oxígeno por géneros. La relación entre frecuencia cardíaca y consumo de oxígeno por segmentos y por género fue lineal, con un coeficiente de correlación mayor de 0.9. Conclusiones: Es posible predecir el consumo de oxígeno de miembros superiores y de miembros inferiores y el VO2 máximo a partir de los valores de la frecuencia cardíaca, la cual puede ser usada como estimador del consumo de oxígeno para los segmentos corporales.
Introduction: The Heart rate is an indicator that can be used to estimate oxygen consumption. It has been used to assess physical work load. However its use to assess the work that does not involve the whole body has not been sufficiently proved. Objective: To determine the relationship between oxygen consumption by body segments and heart rates. Methods: The relationship between heart rate, oxygen consumption and percentage of maximum oxygen consumption by ergospirometry and pulsometry in 30 individuals exposed to maximum loads executed with the whole body, legs and upper limbs was established. Results: Statistically significant differences between maximal oxygen consumption by gender and body segments were found. No significant differences between the proportion of oxygen consumption by genres was found. The relationship between heart rate and oxygen uptake by segment and by gender was linear with a correlation coefficient greater than 0.9. Conclusion: It's possible to predict the arms and legs oxygen consumption and oxygen uptake from the heart rate values, the heart rate can be used as an estimate of the oxygen consumption by body segments.
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Humanos , Adulto , Consumo de Oxígeno , Frecuencia Cardíaca , Fisiología , Salud LaboralRESUMEN
In addition to its role in the pathophysiology of numerous psychiatric disorders, increasing evidence points to serotonin (5-HT) as a crucial molecule for the modulation of neurodevelopmental processes. Recent evidence indicates that the placenta is involved in the synthesis of 5-HT from maternally derived tryptophan (TRP). This gives rise to the possibility that genetic and environmental perturbations directly affecting placental TRP metabolism may lead to abnormal brain circuit wiring in the developing embryo, and therefore contribute to the developmental origin of psychiatric disorders. In this review, we discuss how perturbations of the placental TRP metabolic pathway may lead to abnormal brain development and function throughout life. Of particular interest is prenatal exposure to maternal depression and antidepressants, both known to alter fetal development. We review existing evidence on how antidepressants can alter placental physiology in its key function of maintaining fetal homeostasis and have long-term effects on fetal forebrain development.
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Las Encefalopatías Espongiformes Transmisibles, también llamadas enfermedades priónicas, sonun grupo de enfermedades neurodegenerativas, que afectan una gran variedad de mamíferos. El agenteresponsable de estas patologías se ha identificado como una isoforma anormal de una proteína celular, lacual luego de sufrir un cambio conformacional (prion), adquiere la capacidad de comportarse como unagente infeccioso. Se ha demostrado la capacidad de los priones para cruzar la barrera de especies entreel ganado y los seres humanos; lo cual se ha reflejado en un problema de salud pública que ha afectadogravemente a los países donde se han presentado brotes de estas enfermedades. Las EncefalopatíasEspongiformes Transmisibles se han reportado en una gran cantidad de países y Colombia no ha sido ajenaa la presencia de casos esporádicos humanos, no relacionados con el consumo de material contaminadoprocedente de animales enfermos. Con el presente artículo se pretende dar una visión de la historia y elestado actual de Colombia frente a estas enfermedades, las cuales representan una grave amenaza para lasalud pública y la agrocadena ganadera del país.
Transmissible Spongiform Encephalopaties, also called prion diseases, are a group of neurodegenerativediseases affecting a variety of mammals. The responsible agent consists of an abnormal isoform of a cellularprotein that suffers a conformational change (prion), acquiring the ability of being transmissible. It hasbeen demonstrated prions capacity to cross the species barrier between the cattle and humans; affectingpublic health in countries with reported cases of bovine spongiform encephalopathy. The transmissiblespongiform encephalitis have been reported in a number of countries and Colombia is not the exceptionwith some human sporadic cases, not related with the intake of contaminated material from sick animals.With this manuscript we pretend to give a view of the history and the current state of prion diseases inColombia, which represent a serious threat for the public health and the cattle industry of the country.
As doenças encefalopatias espongiformes transmissíveis, são do grupo de doenças neurodegenerativas,que afetam uma grande variedade de mamíferos. O agente responsável de estas patologias estáidentificado como uma isoforma anormal de uma proteína celular, a qual logo de apresentar umamudança de conformação (prião), adquire a capacidade de comportar-se como um agente infeccioso.Tem-se demonstrado a capacidade que tem o prião para ultrapassar a barreira de espécies entre o gadoe o ser humano; o qual está refletido gravemente aos países onde tem-se apresentado estas doenças.As encefalopatias espongiformes transmissíveis estão reportadas em uma grande quantidade de países.Na Colômbia tem-se apresentado casos esporádicos em humanos, não relacionados com o consumo dematerial contaminado procedente de animais doentes. O presente artigo, busca dar uma visão da historiae o estado atual da Colômbia frente as doenças, as quais representam uma grave ameaça para a saúdepública e da pecuária do pais.
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Animales , Encefalopatía Espongiforme Bovina/epidemiología , PrionesRESUMEN
Veinte vacas cebú comerciales de descarte con edades entre 42 y 72 meses, procedentes del PiedemonteLlanero se utilizaron para realizar un estudio de predicción del peso de la canal utilizando ultrasonidoen tiempo real (UTR). Las vacas cebadas en pastoreo, fueron pesadas y enviadas al frigorífico para sufaenado. Doce horas pre-sacrificio, a cada vaca se tomaron por ecografía las medidas de: área de ojo delomo (AOL), espesor de grasa dorsal (EGD) a nivel de la 12-13 costilla, espesor de glúteo medio (EGM)y espesor de grasa a nivel del anca (GA). Además, se tomaron, el puntaje de condición corporal (PC) yel puntaje de temperamento (PT). Posterior al sacrificio, se recolectó la información de peso de la canalcaliente y fría (PCC y PCF). El análisis estadístico incluyó: estadística descriptiva, correlaciones dePearson, análisis de regresión múltiple entre medidas in vivo, posmortem y para la predicción del pesode la canal. Las vacas tuvieron un promedio de peso vivo (PV) de 408.70 kg. Los promedios de AOL,EGD, EGM, GA, de las vacas fueron 48.87 cm2, 4.16 mm, 69.86 mm y 7.60 mm, respectivamente. El PCpromedio fue de 5.5. Las medidas de PCC y PCF promediaron 208.19 kg y 198.55 kg, respectivamente. Seencontraron correlaciones moderadas (p<0.05) entre AOL y PC y postmortem entre AOL y PCC, lo cualpodría ser indicador cuantitativo para producción. Las medidas de AOL y EG a nivel de la costilla nopresentaron correlación con el peso de la canal. También se encontró una correlación moderada (p<0.05)entre el PC y PCC, que podría ser una herramienta visual útil para estimar el espesor de grasa en vacas antes del faenado. Medidas como AOL y el PV podrían ser usados para predecir aceptablemente el PCCen vacas Cebú de descarte.
Twenty Zebu culling commercial cows aged between 42 and 72 months, from Piedemonte Llanero usedfor a study of prediction of carcass weight using realtime ultrasound (RTU). Cows fattened on pasture,were weighed and sent to the slaugtherhouse for dressing. Twelve hours of pre-slaughter each cow weretaken by ultrasound measures: rib eye area (REA), back fat thickness (BFT) at the 12-13 rib site, depthof gluteus medius (DGM) and thickness fat at the rump (TFR). Furthermore, it was the body conditionscore (BCS) and temperament scores (TS). Post-slaughter, the information was collected from the weightof hot and cold carcasses (WHC and WCC). Statistical analysis included: descriptive statistics, Pearsoncorrelations, multiple regression analysis between measurements in vivo and postmortem for the predictionof carcass weight. The cows had an average weight live (WL) of 408.70 kg. REA, BFT, DGM and TFRaverages for the cows were 48.87 cm2, 4.16 mm, 69.86 mm and 7.60 mm, respectively. BCS average was5.5. WHC and WCC averages were 208.19 kg and 198.55 kg, respectively. We found moderate correlations(p<0.05) between REA with BCS and REA with PCC postmortem, which could be quantitative indicatorfor production. REA and EG measures at the rib site showed no correlation with the carcass weight. Wealso found a moderate correlation (p <0.05) between the BSC and WHC, which could be a useful visualtool to estimate the fat thickness in cows before dressing. Measures such as REA and WL could be used toreasonably predict the WHC Zebu cows culling.
Vinte vacas Zebu comercial de descarte com idade entre 42 e 72 meses, provenientes do PiedemonteLlanero foram utilizadas para um estudo de predição do peso da carcaça com ultra-som em tempo real(RTU). Doze horas de pré-abate, foram tomadas as mensurações por ultra-som: área de olho de lombo(LOA), espessura de gordura dorsal (EGD) na costela 12/13, profundidade de glúteo medius (PGM) eespessura gordura na garupa (EGG). Também foram tomadas as mensurações: escore de condiçãocorporal (ECC) e temperamento (PT). Pós-abate, a informação foi recolhida a partir da peso de carcaçaquente e fria (PCQ e PCF). A análise estatística incluiu: estatística descritiva, correlações Pearson, análisede regressão múltipla entre as medições in vivo e depois da morte para a predição de peso de carcaça. Asvacas apresentaram uma média de peso vivo (PV) de 408.70 kg. A média de LOA, EGD, PGM, EGG foram48.87 cm2, 4.16 mm, 69.86 mm e 7.60 mm, respectivamente. A média foi de 5.5 ECC. As medidas do PCQe PCF média 208.19 kg e 198.55 kg, respectivamente. Encontro-se correlações moderada (p <0.05) entreLOA e ECC postmortem e entre LOA e PCQ, o que poderia ser indicador quantitativo para a produção.As medidas de LOA e EGD na costela mostrou nenhuma correlação com o peso da carcaça. Encontramostambém uma correlação moderada (p <0.05) entre o ECC e o PCQ, o que poderia ser uma útil ferramentavisual para estimar a espessura de gordura de vacas antes do abate. Medidas como LOA e PV poderiam serusadas para prever razoavelmente o PCQ vacas Zebu.
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Animales , Composición Corporal , BovinosRESUMEN
Breeding programs for acid-soil tolerance are desirable as a relatively inexpensive and permanent way for increasing maize (Zea mays L.) yield on these soils. Our objective was to compare the genetic effects controlling the expression of maize traits in acid and non-acid soils. Seven related and one unrelated inbred lines, with different levels of tolerance to acid soil, and their F1, F2, BC1, and BC2 generations were evaluated in four acid and two non-acid soils. Estimates of additive, dominance, and epistatic effects were computed for grain yield, plant height, days to mid-silk, and prolificacy, using the generation means analysis procedure. For all traits the major part of the variation was accounted for by additive and dominance effects, with dominance effects being more important than additive and epistatic effects for both acid and non-acid soils. Epistatic effects were significant for some crosses only, being more pronounced for plant height than for the other traits. Furthermore, epistatic effects were randomly distributed among the crosses and were not related to the grain yield of the single-crosses (F1's) and to the genetic relationships of the inbreds in either type of soil. The results suggest that similar pooled gene effects control the expression of the traits assessed in both acid and non-acid soils.
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Acidez del Suelo/análisis , Zea mays/genética , Análisis de Varianza , Variación Genética , HerenciaRESUMEN
Introducción: En estados avanzados de la EPOC pueden demostrarse alteraciones neurohormonales significativas, que se correlacionan con la aparición de hipercapnia y retención de sodio y agua. No se conoce si hay activación del eje renina-angiotensina-aldosterona en etapas tempranas de la enfermedad, como se ha detectado que ocurre en la enfermedad ventricular izquierda. Objetivo: evaluar la actividad de renina plasmática, un índice de la función del eje renina-angiotensión-aldosterona, en pacientes con EPOC que no han presenta edemas ni descompensación clínica. Pacientes y Métodos: Diez y seis pacientes fueron estudiados con pruebas de función pulmonar (espirometría, curvo flujo-volumen), gasimetría arterial, radiografía del tórax y ecocardiograma transtorácico. En sangre venosa y en condiciones de reposo se determinó actividad de renina plasmática por radioinmunoensayo. Resultados: Se estudiaron 16 pacientes, 14 hombres y 2 mujeres, edad promedio de 61 años con EPOC moderado a severo (promedio del VEF 1 predicho 50 por ciento, relación VEF1/CVF 51 por ciento), PaO2 promedio 52 mm Hg y PaCO2 promedio 34,3 mm Hg, con hipertensión pulmonar moderada a severa (presión sistólica pulmonar promedio 61 mmHg y media pulmonar 41,7) y alteración de la función sistólica del ventriculo derecho. La función ventrícular izquierda presentaba alteración diastólica en 87 por ciento de los sujetos, mientras que la función sistólica era completamente normal, con una fracción de eyección normal (promedio 59,7 por ciento) todos los sujetos estudiados tuvieron actividad de renina plasmática normal. Conclusión: No se detectó alteración en la actividad de renina plasmática en este grupo de pacientes con EPOC estable y sin antecedentes de edemas o disfunción ventricular izquierda. Para alcanzar el verdadero papel de las alteraciones neurohormonales en la fisiopatología de la EPOC es necesario estudiar sujetos con mayor grado de hipercapnia o con diferente función ventricular izquierda.