M2 receptors are required for spatiotemporal sequence learning in mouse primary visual cortex.

Acetylcholine is a neurotransmitter that plays a variety of roles in the central nervous system. It was previously shown that blocking muscarinic receptors with a nonselective antagonist prevents a form of experience-dependent plasticity termed "spatiotemporal sequence learning" in the mouse primary visual cortex (V1). Muscarinic signaling is a complex process involving the combined activities of five different G protein-coupled receptors, M1-M5, all of which are expressed in the murine brain but differ from each other functionally and in anatomical localization. Here we present electrophysiological evidence that M2, but not M1, receptors are required for spatiotemporal sequence learning in mouse V1. We show in male mice that M2 is highly expressed in the neuropil in V1, especially in thalamorecipient layer 4, and colocalizes with the soma in a subset of somatostatin-expressing neurons in deep layers. We also show that expression of M2 receptors is higher in the monocular region of V1 than it is in the binocular region but that the amount of experience-dependent sequence potentiation is similar in both regions and that blocking muscarinic signaling after visual stimulation does not prevent plasticity. This work establishes a new functional role for M2-type receptors in processing temporal information and demonstrates that monocular circuits are modified by experience in a manner similar to binocular circuits.NEW & NOTEWORTHY Muscarinic acetylcholine receptors are required for multiple forms of plasticity in the brain and support perceptual functions, but the precise role of the five subtypes (M1-M5) are unclear. Here we show that the M2 receptor is specifically required to encode experience-dependent representations of spatiotemporal relationships in both monocular and binocular regions of mouse V1. This work identifies a novel functional role for M2 receptors in coding temporal information into cortical circuits.

Memoria de trabajo y planificación como predictores de las competencias matemáticas tempranas

Introducción: La relación entre funciones ejecutivas y habilidades matemáticas ha sido ampliamente estudiada. Sin embargo, no existe consenso respecto de la contribución específica de la memoria de trabajo y la planificación en el desarrollo de competencias matemáticas tempranas. El objetivo de este estudio fue determinar la capacidad predictiva de estos dos dominios ejecutivos sobre las competencias matemáticas de preescolares. Método: Se implementó un diseño no experimental ex post facto, con una muestra de 104 niños/as chilenos/as. La evaluación de sus funciones ejecutivas se realizó con la tarea "inversión de números" de la Batería IV Woodcock-Muñoz para evaluar la memoria de trabajo verbal, la subprueba "Torpo, el topo torpe" del Test de Evaluación Neuropsicológica Infantil (TENI) para evaluar la memoria de trabajo visoespacial y el Test de Laberintos de Porteus para evaluar la planificación. Con el fin de evaluar las habilidades matemáticas se utilizó el Test de Evaluación Matemática Temprana Utrecht (TEMT-U), versión chilena. Se realizaron análisis descriptivos, correlaciones y modelos de regresión múltiple. Resultados: La memoria de trabajo verbal seguida por la memoria de trabajo visoespacial y la planificación fueron los mejores predictores de las competencias matemáticas de los/as niños/as. Conclusiones: Estos resultados sugieren que estas funciones ejecutivas desempeñan un papel clave en el aprendizaje de las matemáticas y aportan información específica a las/os educadoras/es para que puedan planificar sus estrategias de enseñanza en función de las demandas cognitivas que requiere cada habilidad matemática, lo que puede ser una vía potencial para promover mejores logros de aprendizaje en esta importante disciplina.

Introduction: The relationship between executive functions and mathematical skills has been extensively studied. However, there is no consensus regarding the specific contribution of working memory and planning in the development of early mathematical skills. The aim of this study was to determine the predictive capacity of these two executive domains on preschoolers' mathematical skills. Method: A non-experimental ex post facto design was implemented with a sample of 104 Chilean children. The evaluation of their executive functions was performed with the "number inversion" task of the Woodcock-Muñoz IV Battery to assess verbal working memory, the "Clumsy Mole the Clumsy Mole" subtest of the TENI Child Neuropsychological Evaluation Test to assess visuospatial working memory, and the Porteus Maze Test to assess planning. To assess mathematical skills, the Test de Evaluación Matemática Temprana Utretch TEMT-U, Chilean version, was used. Descriptive analyses, correlations and multiple regression models were performed. Results: Verbal working memory followed by visuospatial working memory and planning were the best predictors of children's mathematical skills. Conclusions: These results suggest that these executive functions play a key role in mathematics learning and provide specific information to educators so that they can plan their teaching strategies according to the cognitive demands required by each mathematical skill, which may be a potential way to promote better learning achievements in this important discipline.

Evaluación de sesgos de género en las Guías de Práctica Clínica en Chile / Gender biases in Chilean clinical guidelines

BACKGROUND: Diseases and treatments have different presentations and impact in men and women due to sex and gender differences. This issue justifies a gender differentiated approach in clinical practice guidelines. AIM: To evaluate gender biases in the Clinical Practice Guidelines (CPG) of the Explicit Health Guarantees program (GES) in Chile. MATERIAL AND METHODS: GES CPGs documents published between 2005 and 2019 were reviewed. A keyword search was carried out in the CPGs, and they were classified into five groups according to their degree of incorporation of the sex / gender variables, following the methodology by Tannenbaum et al. Also, the correct use of the concepts about sex and gender was evaluated. RESULTS: Eighty five CPGs were evaluated and 25% have specific recommendations by sex (group 1 and 2). Two percent of guides determined specific parameters by sex in diagnostic tests (group 3). Sixty one percent mention the keywords superficially or only in the section of epidemiology and risk factors, without proposing a sex differentiated management (group 4 and 5). Sixty two percent of guides have an appropriate use of concepts, 22% a wrong usage, and 17% do not refer to sex or gender. CONCLUSIONS: Gender biases are evidenced in most of the GES guidelines.

[Gender biases in Chilean clinical guidelines]. / Evaluación de sesgos de género en las Guías de Práctica Clínica en Chile.

BACKGROUND: Diseases and treatments have different presentations and impact in men and women due to sex and gender differences. This issue justifies a gender differentiated approach in clinical practice guidelines. AIM: To evaluate gender biases in the Clinical Practice Guidelines (CPG) of the Explicit Health Guarantees program (GES) in Chile. MATERIAL AND METHODS: GES CPGs documents published between 2005 and 2019 were reviewed. A keyword search was carried out in the CPGs, and they were classified into five groups according to their degree of incorporation of the sex / gender variables, following the methodology by Tannenbaum et al. Also, the correct use of the concepts about sex and gender was evaluated. RESULTS: Eighty five CPGs were evaluated and 25% have specific recommendations by sex (group 1 and 2). Two percent of guides determined specific parameters by sex in diagnostic tests (group 3). Sixty one percent mention the keywords superficially or only in the section of epidemiology and risk factors, without proposing a sex differentiated management (group 4 and 5). Sixty two percent of guides have an appropriate use of concepts, 22% a wrong usage, and 17% do not refer to sex or gender. CONCLUSIONS: Gender biases are evidenced in most of the GES guidelines.

Calidad de vida y sobrecarga en cuidadores de escolares con discapacidad intelectual / Quality of life and overload in caregivers of school children with intellectual disabilities

Existe escasa evidencia sobre calidad de vida y sobrecarga emocional de cuidadores de estudiantes con discapacidad intelectual. Las investigaciones de los últimos años abordan esta problemática desde la persona adulta con discapacidad grave, ya sea física y neurológica, por ende existe la necesidad de identificar la calidad de vida y nivel de sobrecarga del cuidador a cargo de un estudiante con discapacidad intelectual o retos múltiples. El objetivo de este estudio consistió en evaluar la sobrecarga y calidad de vida de cuidadores de escolares con discapacidad intelectual y retos múltiples de Curicó, Chile. Se realizó un diseño transversal, con una muestra de 137 cuidadores de escolares con discapacidad intelectual leve, moderada y discapacidades múltiples de escuelas municipales, y se aplicaron el Cuestionario de Sobrecarga del Cuidador de Zarit y el Cuestionario de Salud de Calidad de Vida SF36. Los resultados mostraron que el mayor número de escolares se encontró en el nivel de discapacidad intelectual leve con un 62.9%, luego un 19.3% para retos múltiples y un 17.9% para discapacidad moderada. Los cuidadores de niños con discapacidades múltiples presentaron un mayor nivel de sobrecarga emocional y menor calidad de vida en la función, dolor corporal y salud general. Se concluye que es necesario el desarrollo de propuestas, tanto en el ámbito de salud como de educación, que integre a la familia en el proceso formativo y que vele por la calidad de vida de los cuidadores principales de estudiantes con discapacidades, con el fin de fortalecer los procesos de inclusión social y educativa de los escolares.

There is little evidence on the quality of life and emotional overload of caregivers of students with intellectual disabilities. Research of recent years address this problem from the adult with severe disability, whether physical or neurological, therefore there is a need to identify the quality of life and overburden level of the caregiver in charge of a student with intellectual disability or multiple challenges. The objective was to evaluate the overload and quality of life of caregivers of students with intellectual and multiple disabilities of Curicó, Chile. We did across-sectional design, with a sample of 137 caregivers of school children with mild, moderate intellectual disability and multiple disabilities of municipal schools, we applied the Zarit Burden Interview scale for caregivers and the SF36 Health Survey. The average age of caregivers of people with disabilities (n = 140) was 40 years(SD = 12), with a minimum age of 18 and a maximum of 66 years. Regarding the marital status of the caregivers (Table 1), 48.6% corresponded to married, 23.6% single, 13.6% cohabiting, 4.3% widowed and 10% separated. With regard to kinship, 73.6% corresponds to the mother of the scholar with a disability. A greater percentage of the caregivers attended the complete secondary education (32.1%), followed by the basic complete with 20.0%, and without studies with 1.4%. The majority of the respondents were primary caregivers of children in the first cycle of education (56.0%) and 72.0% reported living with 4 or more people in the home. The results showed that the highest number of school children was found at the level of mild intellectual disability with 62.9% following multiple challenges (19.3%) and moderate disability with 17.9%. The 48.1% of the total caregivers of children with multiple challenges presented an intense level of overload. This relationship is statistically significant (χ²= 12.4, p = .015) which indicates that caregivers of students with multiple disabilities present a greater burden. Caregivers of children with multiple disabilities presented a higher level of emotional overload and lower quality of life in the body pain function. The final model of multiple linear regression for the dependent variable overload of the caregiver that presents the best goodness of fit presented an association between multiple challenges and greater overload of the caregiver adjusted by the kinship of the caregiver with the scholar. The data indicate that there is a difference of up to 5.8 points in the overload among caregivers of students with mild, moderate intellectual disability and multiple challenges. We concluded that it is necessary to develop proposals in both health and education that integrates the family in the training process and that ensures the quality of life of the main caregivers of students with disabilities, in order to strengthen the processes of social and educational inclusion of the schoolchildren. At the same time, the results obtained provide key background for future research, in terms of support and information that is required to improve the quality of life of caregivers of students with disabilities, while allowing optimal development for children and thus reduce the level of stress and overload of the family. In the same way, it addresses a paradigm of school inclusion that goes beyond curricular adaptations, allows to propose a comprehensive view among all involved, recognizing that the higher the level of disability, the greater the perception of emotional overload and physical discomfort, being necessary incorporate other support networks for caregivers and their family in general, however, it is considered key that the financing of these activities and intervention be intersectoral, involving entities inthe area of health, education, social-community and work among the most important.

Subtyping of Clostridium difficile PCR ribotypes 591, 106 and 002, the dominant strain types circulating in Medellin, Colombia.

We aimed to achieve a higher typing resolution within the three dominant Clostridium difficile ribotypes (591,106 and 002) circulating in Colombia. A total of 50 C. difficile isolates we had previously typed by PCR-ribotyping, representing the major three ribotypes circulating in Colombia, were analyzed. Twenty-seven isolates of ribotype 591, 12 of ribotype 106 and 11 of ribotype 002 were subtyped by multiple locus variable-number tandem-repeat analysis (MLVA). The presence of the PaLoc genes (tcdA/tcdB), toxin production in culture and antimicrobial susceptibility were also determined. From the total C. difficile ribotypes analyzed, 20 isolates (74%) of ribotype 591, nine (75%) of ribotype 106 and five (45.5%) of ribotype 002 were recovered from patients with Clostridium difficile infection (CDI). MLVA allowed us to recognize four and two different clonal complexes for ribotypes 591 and 002, respectively, having a summed tandem-repeat difference (STRD) <2, whereas none of the ribotype 106 isolates were grouped in a cluster or clonal complex having a STRD >10. Six ribotype 591 and three ribotype 002 isolates belonging to a defined clonal complex were isolated on the same week in two different hospitals. All ribotypes harbored either tcdA+/tcdB+ or tcdA-/tcdB+ PaLoc genes. Moreover, 94% of the isolates were positive for toxin in culture. All isolates were susceptible to vancomycin and metronidazole, while 75% to 100% of the isolates were resistant to clindamycin, and less than 14.8% of ribotype 591 isolates were resistant to moxifloxacina. No significant differences were found among ribotypes with respect to demographic and clinical patients' data; however, our results demonstrated a high molecular heterogeneity of C. difficile strains circulating in Colombia.

Molecular, microbiological and clinical characterization of Clostridium difficile isolates from tertiary care hospitals in Colombia.

In Colombia, the epidemiology and circulating genotypes of Clostridium difficile have not yet been described. Therefore, we molecularly characterized clinical isolates of C.difficile from patients with suspicion of C.difficile infection (CDI) in three tertiary care hospitals. C.difficile was isolated from stool samples by culture, the presence of A/B toxins were detected by enzyme immunoassay, cytotoxicity was tested by cell culture and the antimicrobial susceptibility determined. After DNA extraction, tcdA, tcdB and binary toxin (CDTa/CDTb) genes were detected by PCR, and PCR-ribotyping performed. From a total of 913 stool samples collected during 2013-2014, 775 were included in the study. The frequency of A/B toxins-positive samples was 9.7% (75/775). A total of 143 isolates of C.difficile were recovered from culture, 110 (76.9%) produced cytotoxic effect in cell culture, 100 (69.9%) were tcdA+/tcdB+, 11 (7.7%) tcdA-/tcdB+, 32 (22.4%) tcdA-/tcdB- and 25 (17.5%) CDTa+/CDTb+. From 37 ribotypes identified, ribotypes 591 (20%), 106 (9%) and 002 (7.9%) were the most prevalent; only one isolate corresponded to ribotype 027, four to ribotype 078 and four were new ribotypes (794,795, 804,805). All isolates were susceptible to vancomycin and metronidazole, while 85% and 7.7% were resistant to clindamycin and moxifloxacin, respectively. By multivariate analysis, significant risk factors associated to CDI were, staying in orthopedic service, exposure to third-generation cephalosporins and staying in an ICU before CDI symptoms; moreover, steroids showed to be a protector factor. These results revealed new C. difficile ribotypes and a high diversity profile circulating in Colombia different from those reported in America and European countries.

Proprioceptive assessment battery for patients with below-knee amputation (BEPAT in Spanish) / Batería de evaluación propioceptiva en personas con amputación transtibial, ya protetizadas-BEPAT

Abstract Introduction: Amputation generates various biomechanical and structural changes, creating deficiencies in balance, equilibrium and proprioception. Altered proprioception affects the bodily-space component, as well as postural control and other physical qualities, which require a specific management with physiotherapy intervention. This research was conducted considering that proprioceptive assessment is an adequate and effective tool in physiotherapy but is poorly documented in the literature regarding this population. Objective: To propose and validate a proprioceptive assessment battery in transtibial amputees with prostheses. Materials and methods: Descriptive-purposeful study in which information was gathered to propose a battery test based on scientific evidence available. Results: The propioceptive assessment battery for people with transtibial amputation with prostheses (BEPAT, for its acronym in Spanish), has a high validity of content and construct, according to Palisano criteria, considering that the results for all the items in the battery were above 70%. Conclusions: By means of the BEPAT it will possible to obtain objective and quantitative information on functional alterations, which will improve prosthesis prescription and rehabilitative treatment, as well as strengthen investigative processes in this field.

Resumen Introducción. La amputación trae diversos cambios biomecánicos y estructurales que generan deficiencias en el balance, el equilibrio y la propiocepción. Asimismo, la alteración de la propiocepción afecta el componente corpóreo-espacial, el control postural y demás cualidades físicas, lo cual requiere un manejo específico desde la Fisioterapia. Esta investigación se realizó teniendo en cuenta su función como herramienta adecuada y eficaz dentro de la Fisioterapia, debido a la poca documentación en la literatura de la evaluación propioceptiva en la población escogida. Objetivo. Proponer y validar una batería de evaluación propioceptiva para personas con amputación transtibial, ya protetizadas. Materiales y métodos. Estudio de tipo descriptivo-propositivo que requirió un proceso de recolección de información para proponer una batería de evaluación, basada en la evidencia científica disponible. Resultados. La batería de evaluación de la propiocepción para personas con amputación transtibial ya protetizada (BEPAT), cuenta con alta validez de contenido y constructo según los criterios de Palisano, considerando que los resultados para todos los ítems en la batería se encontraron por encima del 70%. Conclusiones. La creación de la BEPAT permitirá la obtención de información objetiva y cuantitativa sobre las alteraciones funcionales, lo que mejorará la prescripción de prótesis y el tratamiento rehabilitador y fortalecerá los procesos investigativos en el tema.

Effect of variations in the nitrogen loading rate and seasonality on the operation of a free water surface constructed wetland for treatment of swine wastewater.

The aim of this study was to evaluate the effects of variations in the nitrogen loading rate (NLR) and seasonality on the operational efficiency of a free-water surface constructed wetland (FWS) and on the processes involved in total nitrogen (TN) removal in treating swine wastewater. The system, which operated for 550 days, consisted of a FWS mesocosm inoculated with Typha angustifolia L., using swine wastewater from a storage lagoon as an influent. After operating with nitrogen loading rates (NLRs) of 2.0 to 30.2 kg TN ha(-1)·d(-1), the FWS reduced total nitrogen (TN) concentration by between 21.6 and 51.0%, achieving maximum removal (48.2 ± 3.0%) when the system operated at a NLR below 15.0 kg TN ha(-1)·d(-1). Moreover, operations over 25.0 kg TN ha(-1)·d(-1) resulted in a 50.6% decrease in the maximum FWS efficiency, which may have been related to increased anoxic conditions (< 0.5 mg O2 L(-1); -169.8 ± 70.3 mV) resulting from the high concentration of organic matter in the system (12.3 ± 10.5 g TCOD L(-1)), which hindered nitrification. Ammonia volatilization is considered the main method to remove TN, with an average value of 14.4 ± 6.5% (3.1-26.2%). Maximum volatilization occurred during the summer (21.5 ± 2.4°C) at an NLR higher than 25 kg TN ha(-1)·d(-1) (26.6%), favored by higher temperatures (17.3-19.7°C), and high NH4(+)-N (>600.0 9 mg NH4(+)-N L(-1)) and pH levels (7.1-7.9). Uptake by plants accounted for 14.9% of the TN removed, with the vegetative peak in summer (height: 105.3 cm; diameter: 2.1 cm) at an NLR of 25.3 ± 0.3 kg TN ha(-1)·d(-1). However, growth decreased to 94.4% at an NLR of over 25.3 ± 0.3 kg TN ha(-1)·d(-1) (>379.9 mg NH4(+)-N L(-1)) in autumn (17.4 ± 2.4°C). This was associated with the period of plant senescence and the effects of ammonium phytotoxicity (379.9-624.2 mg NH4(+)-N L(-1)) and continued to the end of the study with the complete loss of macrophyte species. Finally, 1.5% of the TN removed was incorporated into the sediments where NH4(+)-N is the main form of nitrogen, with an accumulative value of 2.6 g m(-2).

Distribution and innervation of putative peripheral arterial chemoreceptors in the red-eared slider (Trachemys scripta elegans).

Peripheral arterial chemoreceptors have been isolated to the common carotid artery, aorta, and pulmonary artery of turtles. However, the putative neurotransmitters associated with these chemoreceptors have not yet been described. The goal of the present study was to determine the neurochemical content, innervations, and distribution of putative oxygen-sensing cells in the central vasculature of turtles and to derive homologies with peripheral arterial chemoreceptors of other vertebrates. We used tract tracing together with immunohistochemical markers for cholinergic cells (vesicular acetylcholine transporter [VAChT]), tyrosine hydroxylase (TH; the rate-limiting enzyme in catecholamine synthesis), and serotonin (5HT) to identify putative oxygen-sensing cells and to determine their anatomical relation to branches of the vagus nerve (Xth cranial nerve). We found potential oxygen-sensing cells in all three chemosensory areas innervated by branches of the Xth cranial nerve. Cells containing either 5HT or VAChT were found in all three sites. The morphology and size of these cells resemble glomus cells found in amphibians, mammals, tortoises, and lizards. Furthermore, we found populations of cholinergic cells located at the base of the aorta and pulmonary artery that are likely involved in efferent regulation of vessel resistance. Catecholamine-containing cells were not found in any of the putative chemosensitive areas. The presence of 5HT- and VAChT-immunoreactive cells in segments of the common carotid artery, aorta, and pulmonary artery appears to reflect a transition between cells containing the major neurotransmitters seen in fish (5HT) and mammals (ACh and adenosine).

Distribution and innervation of putative arterial chemoreceptors in the bullfrog (Rana catesbeiana).

Peripheral arterial chemoreceptors have been located previously in the carotid labyrinth, the aortic arch, and the pulmocutaneous artery of frogs. In the present study we used cholera toxin B neuronal tract tracing and immunohistochemical markers for cholinergic cells (vesicular acetylcholine transporter [VAChT]), tyrosine hydroxylase (TH), and serotonin (5HT) to identify putative O2-sensing cells in Rana catesbeiana. We found potential O2-sensing cells in all three vascular areas innervated by branches of the vagus nerve, whereas only cells in the carotid labyrinth were innervated by the glossopharyngeal nerve. Cells containing either 5HT or TH were found in all three sites, whereas cells containing both neurotransmitters were found only in the carotid labyrinth. Cell bodies containing VAChT were not found at any site. The morphology and innervation of putative O2-sensing cells were similar to those of glomus cells found in other vertebrates. The presence of 5HT- and TH-immunoreactive cells in the aorta, pulmocutaneous artery, and carotid labyrinth appears to reflect a phylogenetic transition between the major neurotransmitter seen in the putative O2-sensing cells of fish (5HT) and those found in the glomus cells of mammals (acetylcholine, adenosine, and catecholamines).

Nitrogen behavior in a free water surface constructed wetland used as posttreatment for anaerobically treated swine wastewater effluent.

The aim of this study was to evaluate the behavior of total nitrogen (TN) in its different forms in a Free Water Surface constructed wetland (FWS) used as posttreatment for anaerobically treated swine wastewater. The experiment was conducted in a glasshouse from July 2010 to November 2011. The system consists in a FWS mesocosm inoculated with Typha angustifolia L. using as pretreatment an UASB reactor (upflow anaerobic sludge blanket). The operation are based on the progressive increase of the nitrogen loading rate (NLR) (2.0-30.2 kg TN/ha·d) distributed in 12 loads, with an operational time of 20 d. The results indicate that the behavior of the TN in the FWS, mainly depends on the NLR applied, the amount of dissolved oxygen available and the seasonality. The FWS operated with an NLR between 2.0-30.2 kg TN/ha·d, presents average removal efficiency for TN of 54.8%, with a maximum removal (71.7%) between spring-summer seasons (17.3-21.7°C). The availability of dissolved oxygen hinders the nitrification/denitrification processes in the FWS representing a 0.3-5.6% of TN removed.The main route of TN removal is associated with ammonia volatilization processes (2.6-40.7%), mainly to NLR over 25.8 kg TN/ha· d and with temperatures higher than 18°C. In a smaller proportion, the incorporation of nitrogen via plant uptake was 10.8% whereas the TN accumulated in the sediments was a 5.0% of the TN applied during the entire operation (550 d). An appropriate control of the NLR applied, can reduce the ammonia volatilization processes and the phytotoxicity effects expressed as growth inhibition in 80.0% from 496.0 mg NH(+) 4-N/L (25.8 kg TN/ha·d).

Behavior of Typha angustifolia L. in a free water surface constructed wetlands for the treatment of swine wastewater.

The objective of this study was to evaluate the behavior of Typha angustifolia L. in nitrogen retention in a Free Water Surface Constructed Wetland (FWS) for the swine wastewater treatment over a three-year operating period. Results show that the behavior of Typha angustifolia L. in a FWS for treatment of swine wastewater is affected by nitrogen concentration, seasonal variation and plant establishment in the system. Indeed, the application of Nitrogen Loading Rates (NLR) between 7.1-14.3 kg TN/ha·d removes 40% of Total Nitrogen (TN), where the maximum removal (20-40%) takes place in the spring-summer seasons. However, concentrations higher than 120.3 mg NH4 (+)-N/L significantly decrease (P = 0.004) diametrical growth by 55%. However, it was possible to estimate that NLR >14.3 kg TN/ha·d increased biomass production and plant uptake in Typha angustifolia L. during the period analyzed. Additionally, aboveground biomass values were between 1.509.6-2.874.0 g/m(2) and nitrogen uptake 27.4-40.8 g/m(2), where this last value represents 29% of the TN applied during the study. Finally, the TN accumulation in sediments represents less than 2% of the TN incorporated during this period. These results show that an increase of 50% of the TN in sediments increases plant abundance in 73%, which is related to the mineralization processes favored in the system during the last year of operation.

Circadian and circannual rhythms in the metabolism and ventilation of red-eared sliders (Trachemys scripta elegans).

Endogenous circadian and circannual rhythms may exist in the metabolism, ventilation, and breathing pattern of turtles that could further prolong dive times during daily and seasonal periods of reduced activity. To test this hypothesis, turtles were held under seasonal or constant environmental conditions over a 1-yr period, and in each season, V(O)(2) and respiratory variables were measured in all animals under both the prevailing seasonal conditions and the constant conditions for 24 h. Endogenous circadian and circannual rhythms in metabolism and ventilation occurred independent of ambient temperature, photoperiod, and activity, although long-term entrainment to daily and seasonal changes in temperature and photoperiod were required for them to be expressed. Metabolism and ventilation were always higher during the photophase, and the day-night difference was greater at any given temperature when the photoperiod was provided. When corrected for temperature, turtles had elevated metabolic and ventilation rates in the fall and spring (corresponding to the reproductive seasons) and suppressed metabolism and ventilation during winter. The strength of the circadian rhythm varied seasonally, with proportionately larger day-night differences in colder seasons. Daily and seasonal cycles in ventilation largely followed metabolism, although daily and seasonal changes did occur in the breathing pattern independent of levels of total ventilation. These endogenous circadian and circannual changes in metabolism, ventilation, and breathing pattern prolonged dive times at night and in winter and may serve to reduce the costs of breathing and transport and risk of predation.

Daily and seasonal rhythms in the respiratory sensitivity of red-eared sliders (Trachemys scripta elegans).

The purpose of the present study was to determine whether the daily and seasonal changes in ventilation and breathing pattern previously documented in red-eared sliders resulted solely from daily and seasonal oscillations in metabolism or also from changes in chemoreflex sensitivity. Turtles were exposed to natural environmental conditions over a one year period. In each season, oxygen consumption, ventilation and breathing pattern were measured continuously for 24 h while turtles were breathing air and for 24 h while they were breathing a hypoxic-hypercapnic gas mixture (H-H). We found that oxygen consumption was reduced equally during the day and night under H-H in all seasons except spring. Ventilation was stimulated by H-H but the magnitude of the response was always less at night. On average, it was also less in the winter and greater in the reproductive season. The data indicate that the day-night differences in ventilation and breathing pattern seen previously resulted from daily changes in chemoreflex sensitivity whereas the seasonal changes were strictly due to changes in metabolism. Regardless of mechanism, the changes resulted in longer apneas at night and in the winter at any given level of total ventilation, facilitating longer submergence at times of the day and year when turtles are most vulnerable.

Autocuidado de mujeres en etapa de menopausia en Toluca, México / Autocuidado de Mulheres na Etapa da Menopausa em Toluca, México / Self care of women in the menopause stage in Toluca, Mexico

La mujer en etapa de menopausia está expuesta a factores de riesgo que disminuyen con prácticas de autocuidado. El objetivo fue identificar prácticas de autocuidado en la menopausia. Estudio cuantitativo, exploratorio, con muestra probabilística aleatória simple, utilizando EPI INFO 2000, con 95 por cento de confianza, 5 por cento máximo de error, con 354 mujeres...

Anemia ferropriva: respuestas clínica y de laboratorio a dos presentaciones de hierro oral / Iron fediciency anemia: clinic and laboratory responses to two oral intake of iton preparation

Se estudiaron 457 niños en un periodo de 21 meses que llegaron al Instituto Nacional de Pediatría (INP) con posible anemia ferropriva. Solamente 191 la tuvieron; de ellos, 57 forman parte del análisis final. Se formaron dos grupos para analizar la respuesta a la administración oral de dos presentaciones de hierro. Uno en la forma de complejo orgánico de hieroo hidróxido férrico polimaltosado (Grupo 1) y otro en la forma de complejo divalente slfato ferroso (Grupo 2) a la dosis de 5 mg de hierro elemental Kg/día, después de cada uno de los alimentos. La respuesta al tratamiento se consideró como positiva o negativa tomando en cuenta el número de parámetros que se modificaron al término de cuatro semanas de tratamiento. Se aceptó como positiva la elevación de los niveles de Hb, Ht, capacidad de fijación de hierro (CFT) e índice de saturación (IS). Las respuestas favorables en todos los parámetros, obvservadas en los pacientes del Grupo 2 en el plazo fijado, permiten considerar al sulfato ferroso como de elección en el tratamiento de la anemia ferropénica

Síndrome hemorrágico en el recién nacido / Hemorragic syndrome in the newborn infant

En el período de 1979 a 1983 ingresaron al Servicio de Neonatología 1485 recién nacidos de los cuales se estudiaron 214 pacientes. El objetivo de este estudio fue determinar las causas más frecuentes de síndrome hemorrágico en el recién nacido. El 63% de los pacientes tuvieron hemorragia intracraneana, el 20% enfermedad hemorrágica del recién nacido, 10% coagulación intravascular disemanada., 5% hemorragía pulmonar y 1% hemofilia. La causa más frecuente de este síndrome fue la hemorragia intracraneana no asociada a un defecto en la hemostasis propiamente dicha. La enfermedad hemorragica del recién nacido fue la segunda causa, por lo que se recomienda la utilización profiláctica de vitaminas K en todos los neonatos (1 mg/kg peso I.M.). Los recién nacidos de pretérmino infectados con hipoxia severa deben considerarse de alto riesgo a desarrollar coagulación intravascular disemanada. La mortalidad en muestra serie fue de 63% por lo que se recomienda una vigilancia periódica con pruebas de tendencia hemorrágicas completas, corrección de factores predisponentes y manejo específico en caso necesario