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Introducción: Actualmente la función de la telefonía celular conecta al usuario con el mundo a través del internet dándole acceso a un cúmulo de información. A pesar de todos los beneficios, existen problemas en salud a consecuencia del uso prolongado, se manifiestan en ansiedad, irritabilidad, inquietud y malestar general; alteraciones de la sensibilidad, lesiones cervicales, problemas visuales y cefalea. Objetivos: Analizar la existencia de problemas de salud asociados al uso del teléfono celular en estudiantes de enfermería universitarios. Analizar la relación entre el uso del teléfono celular y los problemas de salud físicos y psicoemocionales de estudiantes de enfermería universitarios. Metodología: Estudio cuantitativo no experimental, de corte transversal, descriptivo, prolectivo y correlacional. Se aplicó la encuesta "Escala de Uso Problemático del Teléfono Celular Modificada" a 265 estudiantes de enfermería de FES Iztacala. Resultados: El 57% de la población usa su teléfono celular para redes sociales. En los problemas físicos, 32% de estudiantes inician con problemas leves, 5% moderados y 1% graves. En los problemas psicoemocionales, 25% inician con problemas leves, 4% moderados y 2% graves. Hay asociación entre el uso y problemas de salud psicoemocionales (rp=0.659, p=0.000), al igual que con problemas de salud físicos (rp=0.541, p=0.000). Discusión: De acuerdo con Alonso-Fernández los síntomas se desarrollan más profundamente en la mente que en el cuerpo pues el tiempo de exposición afecta órganos y sistemas, principalmente el sistema nervioso implicando la psique. Conclusiones: El uso frecuente del teléfono celular está vinculado al acceso a internet, haciendo que el usuario pase más tiempo utilizando el dispositivo. Aunque son pocos los casos que presentan problemas, es indispensable que enfermería se involucre en estos tópicos, para el desarrollo de estrategias preventivas en la aparición de los problemas de salud asociados.

Introduction: Currently cellphones connect the users with the world through internet, giving them access to lots of information. In spite of all the benefits, there are health problems caused by the prolonged usage of it, they're manifested as anxiety, irritability, restlessness and physical discomfort; sensibility alterations, cervical injuries, visual problems and headache. Objectives: To analyze the existence of health problems associated to the cellphone usage among college nursing students. To analyze the relationship between the cellphone usage and physical and phycho-emotional health issues among college nursing students. Methodology: Prolective, correlational, descriptive, cross-sectional and non-experimental quantitative study. The survey "Escala de Uso Problemático del Teléfono Celular Modificada" was applied to 265 nursing students from FES Iztacala. Results: 57% of the population uses its phone for social networks. About physical problems, 32% of students are beginning to experience subtle problems, 5% moderate problems and 1% severe problems. About psycho-emotional issues, 25% are beginning to experience subtle issues, 4% moderate issues, and 2% severe issues. There's an association between cellphone usage and psycho-emotional health issues (rp=0.659, p=0.000) as well as with physical problems (rp=0.541, p=0.000). Discussion: According to Alonso-Fernández the symptoms are developed deeper on the mind than on the body due to exposition time the affects organs and systems, mainly the nervous system implying the psyche. Conclusions: The frequent usage of mobile phones is linked to the internet access, so the user spends more time using the device. Although the cases that present problems are few, it is essential for nursing to get involved in these topics in order to develop precautionary strategies in the appearance of related health issues.

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The study of genes associated with host defense mechanisms, such as the A2M gene, plays a critical role in preventing diseases that reduce milk yield and its constituents. The aim of this study was to identify polymorphisms in the A2M gene in Murrah buffaloes (Bubalus bubalis), and investigate their associations with milk yield, fat and protein production, fat and protein percentages, and somatic cell count. Hair follicle samples of 136 animals were collected for DNA extraction, and polymorphisms were identified by polymerase chain reactions and sequencing. Statistical analyses were performed to ascertain the allelic and genotypic frequencies, the Hardy-Weinberg equilibrium, and association analysis was conducted between the polymorphisms and the traits studied. Comparative analysis between buffalo and bovine sequences revealed seven nucleotide substitutions. Alignments among the buffalo sequences identified three single nucleotide polymorphisms (SNPs), including one in exon 29, g.241A>G, which was used in subsequent statistical analyses. A Hardy-Weinberg test indicated that this SNP was in equilibrium in this population, and was significantly associated (P < 0.05) with fat production and fat and protein percentages. Therefore, this SNP can be used as a molecular marker for these traits.

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Because of the importance of reproduction in stock breeding systems, it is necessary to find selection criteria that increase reproductive efficiency. The aim of this study was to estimate genetic parameters for the probability of conception on first service (PROB) in Murrah heifers, and its association with other traits of economic interest [age at first calving (AFC), service period, calving interval and milk yield at 270 days], with the purpose of evaluating their use as selection criteria. Reproductive information and first lactation records of 1200 Murrah heifers were used to perform two-trait analyses between PROB and the other characteristics. Bayesian inference was used to estimate the variance components, considering PROB as threshold and the other as linear factors. The results demonstrate that this trait has heritability of 0.15, indicating the possibility of a genetic gain by using it for selection. With respect to the genetic correlation estimates, the only high-magnitude association was with AFC (-0.899), which is the current criterion indicating sexual precocity of females. In the light of the parameters estimated, the first-service pregnancy rate is an alternative for indication of sexual precocity, although presenting a smaller genetic gain than the current standard AFC. Nevertheless, additional research should be conducted regarding this trait to assess the economic importance of its use in dairy buffalo production systems.

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The diacylglycerol-O-transferase 1 gene is a positional and functional candidate for milk composition traits. The objective of this study was to evaluate the segregation of the variable number of tandem repeat polymorphisms in the regulatory region of diacylglycerol-O-transferase 1 gene in a water buffalo herd, and to assess the association of this mutation with milk production traits. For this purpose, 196 Murrah buffalo cows were genotyped by PCR. The association of the marker with total milk, fat, and protein yields at 305 d of lactation, milk fat and protein percentage, and somatic cell scores were evaluated by single-trait analyses using a generalized mixed model. Two segregating alleles were identified in the population. The allele with 2 repeats affected fat percentage favorably. The present results suggest that this polymorphism is an interesting marker to include in the genetic evaluation of buffaloes.

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The objective of this study was to compare the multi-trait model using pedigree information and a model using genomic information in addition to pedigree information. We used data from 5896 lactations of 2021 buffalo cows, of which 384 were genotyped using the Illumina Infinium(®) bovine HD BeadChip, considering seven traits related to milk yield (MY305), fat (FY305), protein (PY305), and lactose (LY305), percentages of fat (%F) and protein (%P), and somatic cell score (SCS). We carried out two analyses, one using phenotype and pedigree information (matrix A) and the other using the relationship matrix based on pedigree and genomics information (a single step, matrix H). The (co)variance components were estimated using multiple-trait analysis by the Bayesian inference method. The model included the fixed effects of contemporary groups (herd-year and calving season), and the age of cow at calving as (co)variables (quadratic and linear effect). The additive genetic, permanent environmental, and residual effects were included as random effects in the model. The estimates of heritability using matrix A were 0.25, 0.22, 0.26, 0.25, 0.37, 0.42, and 0.17, while using matrix H the heritability values were 0.25, 0.24, 0.26, 0.26, 0.38, 0.47, and 0.18 for MY305, FY305, PY305, LY305, %F, %P, and SCS, respectively. The estimates of breeding values in the two analyses were similar for the traits studied, but the accuracies were greater when using matrix H (higher than 8% in the traits studied). Therefore, the use of genomic information in the analyses improved the accuracy.

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To define the best strategies for genomic association studies and genomic selection, it is necessary to determine the extent of linkage disequilibrium (LD) and the genetic structure of the study population. The current study evaluated the transference of genomic information contained in the Illumina BovineHD BeadChip from cattle to buffaloes, and assessed the extent of the LD in buffaloes. Of the 688,593 bovine single nucleotide polymorphism (SNP) that were successfully genotyped from the 384 buffalo samples, only 16,580 markers were polymorphic, and had minor allele frequencies greater than 0.05. A total of 16,580 polymorphic SNPs were identified, which were uniformly distributed throughout the autosomes, because the density and mean distance between markers were similar for all autosomes. The average minor allele frequency for the 16,580 SNPs was 0.23. The overall mean LD for pairs of adjacent markers was 0.29 and 0.71, when measured as for r2 and |D'|, respectively. The 16,580 polymorphic SNPs were matched to Bos taurus chromosome in the current bovine genome assembly (Btau 4.2), and could be utilized in association studies. In conclusion, the Illumina BovineHD BeadChip contains approximately 16,580 polymorphic markers for the water buffalo, which are broadly distributed across the genome. These data could be used in genomic association and genomic selection studies; however, it might be necessary to develop a panel with specific SNP markers for water buffaloes.

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The objective of this study was to estimate variance components and genetic parameters for accumulated 305-day milk yield (MY305) over multiple ages, from 24 to 120 months of age, applying random regression (RRM), repeatability (REP) and multi-trait (MT) models. A total of 4472 lactation records from 1882 buffaloes of the Murrah breed were utilized. The contemporary group (herd-year-calving season) and number of milkings (two levels) were considered as fixed effects in all models. For REP and RRM, additive genetic, permanent environmental and residual effects were included as random effects. MT considered the same random effects as did REP and RRM with the exception of permanent environmental effect. Residual variances were modeled by a step function with 1, 4, and 6 classes. The heritabilities estimated with RRM increased with age, ranging from 0.19 to 0.34, and were slightly higher than that obtained with the REP model. For the MT model, heritability estimates ranged from 0.20 (37 months of age) to 0.32 (94 months of age). The genetic correlation estimates for MY305 obtained by RRM (L23.res4) and MT models were very similar, and varied from 0.77 to 0.99 and from 0.77 to 0.99, respectively. The rank correlation between breeding values for MY305 at different ages predicted by REP, MT, and RRM were high. It seems that a linear and quadratic Legendre polynomial to model the additive genetic and animal permanent environmental effects, respectively, may be sufficient to explain more parsimoniously the changes in MY305 genetic variation with age.

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Mucociliary activity is an important clearance mechanism in the respiratory system of air breathing vertebrates. Substance P (SP) and acetylcholine play a key role in the stimulation of the mucociliary transport in the frog palate. In this study, retrograde neuronal tracing was combined with immunocytochemistry for SP and choline acetyl transferase (ChAT) in the trigeminal ganglion and for neurokinin-1 receptor (NK1R) in the palate of Rana pipiens. The cells of origin of the palatine nerve were identified in the trigeminal ganglion using the retrograde tracer Fluorogold (FG). Optimal labeling of FG cells in the trigeminal ganglion was obtained at 96 h of exposure. Immunoflorescent shows that SP and acetylcholine are co-localized in 92% of the cells labeled with FG in the trigeminal ganglion. NK1 receptors were found in the membrane of epithelial and goblet cells of the palate. Ultrastructural study of the palate showed axonal-like endings with vesicles in connection with epithelial and goblet cells. These results further support the concerted action of both neurotransmitters in the regulation of mucociliary activity in the frog palate.

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La autora presenta, derivado de su experiencia nacional e internacional, la potencialidad de la mercadotecnia como una herramienta en función de la gestión sanitaria, ya que ofrece la posibilidad de detectar y dar respuesta a las necesidades de salud a partir de la investigación, la evaluación y análisis de la demanda sanitaria, la satisfacción de trabajadores y pacientes, así como realizar esta identificación para anticipar y satisfacer ambos requerimientos, demostrando que es un instrumento de utilidad para el cambio de la organización en función del cumplimiento cabal de los objetivos sanitarios a la luz de los paradigmas que actualmente sustentan las políticas de salud.

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The morphology and distribution of TH-like immunoreactive (TH-IR) cells in the retina of Rana pipiens were studied in retinal whole mounts and in radial and horizontal sections. A large majority (96%) of the immunoreactive cells were found in the inner nuclear layer while a few cells were found in the ganglion cell layer. All TH-IR cells had round to oval somata with average diameter of 10 microm. The 2-4 primary processes of these cells distributed extensively to sublamina 1 of the inner plexiform layer (IPL) and sparsely to sublamina 5. Two groups of TH-IR cells were distinguished: one, designated thin cells, had only thin (<2 microm diameter) primary processes; the second, designated thick cells, had one or more primary processes with diameter(s) exceeding 2 microm for a distance of 5 microm or more from the soma. The thin cells did not significantly differ from the thick cells in soma diameter, number of primary processes, horizontal spread of processes or vertical lamination of processes. Nearest neighbor analyses of the two types revealed that the population of TH-IR cells (thick and thin together) have an orderly distribution while the thick cells alone are more randomly distributed, indicating that the thick cells do not comprise a functional population. The total number of TH-IR cells varied between retinas; the variability was due principally to variation of thin cell density. It is hypothesized that the thick cells are a subpopulation of the TH-IR cells which are in a particular physiological state at the time of fixation.

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Immunocytochemical techniques were employed to locate somatostatin (SS)-containing cells in the retina of the 13-lined ground squirrel (Spermophilus tridecemlineatus). In normal retinas immunostain was limited to neuronal processes, yet distinctly labeled somata were detected in retinas of animals pretreated with colchicine. Labeled cell bodies were located in the outermost and innermost portions of the inner nuclear layer (INL) and in the ganglion cell layer (GCL). The largest population of SS-like immunoreactive neurons was found in the innermost INL. These cells were identified as small and medium sized amacrine cells whose soma diameters ranged from 4 to 14 microns. A smaller population of immunoreactive cells was observed in the outermost region of the INL. These cells, presumptive horizontal cells, were found mainly in peripheral regions of the retina. Immunoreactive cells in the GCL were of two types: displaced amacrines, and retinal ganglion cells. SS-positive axons in the optic fiber layer suggest that some of the immunoreactive GCL neurons were ganglion cells, and it is our opinion that these cells belong to a class of associational ganglion cells previously identified in other species.

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