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Introduction: Teenage pregnancy is defined as a pregnancy occurring between ages 10 and 19 (Loredo-Abdlá et al., 2017; Belitzky, 1985; Kaplanoglu et al., 2015), and is associated with increased morbidity and mortality for both mother and child. Several factors have been identified with increased risk of a teenage pregnancy, including incomplete sexual education awareness and increased exposure at a young age. In addition, an earlier onset of sexual intercourse, or coitarche, has been linked to a higher risk of teenage pregnancy. Early menarche, defined as first menstruation before the age of 12 has been previously identified as a risk factor for an earlier coitarche, possibly linking an early menarche with a higher incidence of teenage pregnancy. This study aims to compare and determine the relationship between the incidence of teenage pregnancy with early menarche and coitarche in a low income setting. Design Setting Participants Interventions Main Outcome Measures: A cross sectional review of electronic records of women admitted for delivery in a second level center in northeastern Mexico, being a low-income setting, where 814 teenage and 1474 adult mothers were included. Results: Primigravid teenagers had earlier menarche and coitarche than adult counterparts and opted for postpartum contraception more frequently. Linear regression analysis revealed significant unadjusted beta coefficients between age at first pregnancy and coitarche (0.839) and menarche (0.362). Menarche and coitarche had a significant linear regression association of 0.395. Conclusion: We found amongst primigravid patients that teenagers had earlier menarche and coitarche than adults, which in turn correlated to their age at their first pregnancy.
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Agro-industrial wastes such as wheat husk (WH) are renewable sources of organic and inorganic substances, including cellulose, lignin, and aluminosilicates, which can be transformed into advanced materials with high added value. The use of geopolymers is a strategy to take advantage of the inorganic substances by obtaining inorganic polymers, which have been used as additives, e.g., for cement and refractory brick products or ceramic precursors. In this research, the WH native to northern Mexico was used as a source to produce wheat husk ash (WHA) following its calcination at 1050 °C. In addition, geopolymers were synthesized from the WHA by varying the concentrations of the alkaline activator (NaOH) from 16 M to 30 M, namely Geo 16M, Geo 20M, Geo 25M, and Geo 30M. At the same time, a commercial microwave radiation process was employed as the curing source. Furthermore, the geopolymers synthesized with 16 M and 30 M of NaOH were studied for their thermal conductivity as a function of temperature, in particular at 25, 35, 60, and 90 °C. The chemical composition of the WHA, determined by ICP, revealed a SiO2 content close to 81%, which is similar to rice husk. The geopolymers were characterized using various techniques to determine their structure, mechanical properties, and thermal conductivity. The findings showed that the synthesized geopolymers with 16M and 30M of NaOH had significant mechanical properties and thermal conductivity, respectively, compared to the other synthesized materials. Finally, the thermal conductivity regarding the temperature revealed that Geo 30M presented significant performance, especially at 60 °C.
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The structural modification of biopolymers is a current strategy to develop materials with biomedical applications. Silk fibroin is a natural fiber derived from a protein produced by the silkworm (Bombyx mori) with biocompatible characteristics and excellent mechanical properties. This research reports the structural modification of silk fibroin by incorporating polyaniline chain grafts through a one-pot process (esterification reaction/oxidative polymerization). The structural characterization was achieved by 1H-NMR and FT-IR. The morphology was studied by scanning electron microscopy and complemented with thermogravimetric analysis to understand the effect of the thermal stability at each step of the modification. Different fibroin silk (Fib): polyaniline (PAni) mass ratios were evaluated. From this evaluation, it was found that a Fib to PAni ratio of at least 1 to 0.5 is required to produce electroactive polyaniline, as observed by UV-vis and CV. Notably, all the fibroin-g-PAni systems present low cytotoxicity, making them promising systems for developing biocompatible electrochemical sensors.
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INTRODUCTION: There is a high rate of deliveries in adolescents in Mexico. This age group is vulnerable to obstetric complications, including lacerations of the anal sphincter. OBJECTIVE: To determine the prevalence of third and fourth degree perineal tears in adolescents during childbirth, and to evaluate risk factors in comparison with deliveries with lacerations of adult women. METHODS: All obstetric care episodes were reviewed from a public tertiary hospital data in Monterrey, Mexico in 2014. Age, primiparity, delivery instrumentation, episiotomy, body mass index, product weight and tear´s degree were documented at the deliveries with tears of third and fourth degree. RESULTS: The prevalence of third and fourth degree tears of 2.0% was found in the general population, being adolescents the most affected with 2.5%. The unadjusted odds ratio of high-grade tears in adolescent females at delivery, compared to adult females, was 1.36 (95% CI = 0.99-1.86, p= 0.05). No difference was found when comparing risk factors among high-grade tear deliveries in adolescents versus adults. CONCLUSIONS: A higher prevalence than previous reported for high grade tears during delivery was found. The data suggest adolescence as a risk factor for high-grade tears during delivery.
INTRODUCCIÓN: En México hay una elevada tasa de partos en adolescentes. Este grupo es vulnerable para complicaciones obstétricas, entre ellas laceración del esfínter anal. OBJETIVO: Conocer la prevalencia de desgarros perineales de tercer y cuarto grado en adolescentes durante el parto y evaluar factores de riesgo en comparación con partos con laceración de mujeres adultas. MÉTODOS: Se revisaron todas las atenciones obstétricas en un hospital publico de tercer nivel en Monterrey, Nuevo León, México en el año 2014. Se documentó edad, primiparidad, instrumentación del parto, realización de episiotomía, índice de masa corporal, peso del producto y grado del desgarro en los partos que presentaron desgarros de tercer y cuarto grado. RESULTADOS: Se encontró una prevalencia general de 2.0% de desgarros de tercer y cuarto grado y en adolescentes de 2.5%. La razón de momios sin ajustar de desgarros de alto grado en mujeres adolescentes en comparación con mujeres adultas fue de 1.36 (IC 95%= 0.99-1.86, p= 0.05). No se encontró diferencia al comparar factores de riesgo entre los partos con desgarro de alto grado en adolescentes contra adultas. CONCLUSIONES: Se encontró una prevalencia mayor a lo reportado de desgarros de alto grado durante el parto. Los datos sugieren a la adolescencia como factor de riesgo para desgarros de alto grado.
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Canal Anal/lesões , Lacerações/epidemiologia , Complicações do Trabalho de Parto/epidemiologia , Períneo/lesões , Adolescente , Adulto , Episiotomia/estatística & dados numéricos , Feminino , Humanos , Trabalho de Parto , Lacerações/etiologia , México/epidemiologia , Gravidez , Gravidez na Adolescência , Prevalência , Fatores de Risco , Adulto JovemRESUMO
Polyaniline/iota-carrageenan (ι-CGN) biocomposites were synthesized via in situ methodology using ammonium persulfate as the oxidizing agent. Both ionic (band at 1131 cm(-1)) and hydrogen bond (bands at 2500 and 3500 cm(-1)) interactions between polyaniline and ι-CGN were determined by infrared spectroscopy. Such intermolecular interactions provided the biocomposites with a cross-linked structure that provided the materials with hydrogel behavior. Biocomposite electro-conductivity, determined by the 4-probe technique, was in the range of semiconductors (10(-3) to 10(-2) S cm(-1)); whereas electro-activity, assessed by cyclic voltammetry, showed the oxidation-reduction transitions typical of polyaniline. Based on the properties of polyaniline and ι-CGN, some applications for the new materials in the field of biosensor design, electrochemical capacitors, or tissue engineering scaffolds are possible. It is worth saying that both electro-conductive and electro-active properties of polyaniline/ι-CGN biocomposites are reported here for the first time.
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Compostos de Anilina/síntese química , Materiais Biocompatíveis/síntese química , Carragenina/síntese química , Condutividade Elétrica , Compostos de Anilina/metabolismo , Materiais Biocompatíveis/metabolismo , Carragenina/metabolismoRESUMO
Miniemulsion polymerization was used as the synthetic method to produce clay/poly(methyl methacrylate) nanocomposites. Two kinds of interfacial interactions clay-polymer particle were observed by electron microscopy, one where the polymer particles are adhered on the surface of the larger fragments of clay, and another where nanometric fragments of clay are encapsulated by polymer particles. Variations in the glass transition temperature (T(g)) and thermomechanical properties of the matrix, as function of clay content, were observed. In particular, at the highest clay loading (1.0 wt%) depression of T(g) and thermomechanical properties were observed. The increased clay-polymer matrix interfacial area appears to be the conditioning factor that determines such behavior.
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Silicatos de Alumínio/metabolismo , Nanocompostos/efeitos da radiação , Nanocompostos/ultraestrutura , Polimerização/efeitos da radiação , Polimetil Metacrilato/metabolismo , Argila , Microscopia Eletrônica , TemperaturaRESUMO
Anilinium dodecylsulfate was prepared from aniline and sodium dodecylsulfate. The critical micellar concentration of the salt was determined using electrical conductimetry, which revealed that the change of countercation, sodium by anilinium, reduced the critical micellar concentration with respect to the conventional counterpart, sodium dodecylsulfate. The anilinium dodecylsulfate was used as the surfmer in the synthesis of polystyrene/polyaniline core-shell composites, first performing as the surfactant to stabilize the emulsion polymerization of styrene, and later as the monomer to synthesize polyaniline via oxidative polymerization. Here, the surfmer function was directed toward the external phase instead of to the internal phase, as with conventional surfmers with carbon-carbon double bonds. Consequently, the term inverse surfmer is proposed. Analyses of its composite microstructure using electron microscopy and thermogravimetric analysis confirmed the core-shell arrangement.
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Compostos de Anilina/síntese química , Poliestirenos/síntese química , Tensoativos/química , Compostos de Anilina/química , Condutividade Elétrica , Micelas , Tamanho da Partícula , Poliestirenos/química , Dodecilsulfato de Sódio/química , Propriedades de Superfície , Tensoativos/síntese químicaRESUMO
In this study, carbon black/polystyrene electrically conductive composites were obtained by suspension polymerization technique. The composite was characterized using transmission electron microscopy, which indicated two outstanding features concerning to the carbon black; first, that the carbon particles were adsorbed onto the surface of the polystyrene particles, similarly as in the Pickering emulsion phenomenon and second, that the primary aggregate structure of the carbon black was significantly affected by the dispersion process. On the other hand, the composite resistivity was in the order of 200 Ωcm, which was attributed to the direct contact of primary carbon black particles (percolation) and not to the tunneling effect. The obtained composite was evaluated as the electrically conductive element in SBR matrix.
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La profesión médica es un tipo específico de ocupación que da respuesta a los requerimientos económicos, políticos y sociales de la comunidad. Sin embargo, en el ámbito de las profesiones relacionadas con la salud, dicho concepto trasciende este entorno al entrar en juego la perspectiva ética en la que, idealmente, el profesional de la salud antepone los intereses de los demás a los propios. De esta manera, la profesión médica se convierte en una forma de vida regida por principios éticos y guiada por los más altos estándares de profesionalismo, constituyéndose en una vocación y no en una simple ocupación. Para devolver a la profesión médica su vocación distintiva, es esencial analizar las motivaciones intrínsecas y la ética de vida de las nuevas generaciones de médicos y, a partir de ahí, desarrollar a manera de competencias conocimientos, habilidades, actitudes y valores que propicien el desarrollo del profesionalismo, logrando finalmente una mejor relación médico-paciente, situando el bienestar de este último como principal interés.
The medical profession is a specific kind of occupation that responds to the economic, political and social requirements of the community.Nevertheless, in the health care professions, that concept goes even further when the ethical perspective becomes involved. Ideally, health care professionals give priority to the needs of othersindividually or collectively and place their own needs second. In this way, medicine becomes in not just an occupation, but a vocation and a way of life ruled by ethical principles and guided by high professional standards. To restore medicines distinctive vocation, it is essential to analyze the intrinsic motivations and life ethics of new generations of physicians and, on that basis, to begin to develop in the manner of profi ciencies the knowledge, abilities, attitudes and values that enhance professionalism. In the end, this will provide for a better physician-patient relationship, by invariably giving priority to the patients best interests.
A profissão médica é uma ocupação específi ca que responde às demandas econômicas, políticas e sociais da comunidade. No entanto, no domínio das profissões relacionadas com a saúde, o conceito vai além deste ambiente, já que entra em jogo a perspectiva ética, na que idealmente o profissional de saúde põe os interesses dos outros acima dos seus próprios. Por tanto, esta profissão torna-se um modo de vida orientado por princípios éticos e guiado por altos padrões de profissionalismo. Conseqüentemente, é uma vocação enão uma simples ocupação. Se desejamos que a profissão retorne a sua vocação distinta, é essencial analisar as motivações intrínsecase a ética de vida das novas gerações de médicos e, a partir daí, desenvolver conhecimento, habilidades, atitudes e valores semelhantes a competências conducentes ao desenvolvimento do profissionalismo para conseguir uma melhor relação médico-paciente cujo interesse primário seja o bem-estar de este último.
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Educação Médica , Ética , Ocupações em Saúde , MédicosRESUMO
Se revisaron 263 casos de Primigesta Adolescentes en el Hospital de Gineco Obstetricia de Garza García, N. L. de la Subsecretaría Estatal de Salud, de Enero a Diciembre de 1995. Se formaron dos grupos: Uno de 12 a 15 años con 79 (30.1 por ciento) y el segundo de 16 a 18 años con 184 (69.9 por ciento) (P<0.001). En la Unión Libre y Embarazo Pretérmino se encontraron diferencias significativas entre ambos grupos, con una mayor proporción de Primer grupo, (p>0.05), menor control prenatal en las jóvenes con 31.6 por ciento contra 23.3 por ciento, en las complicaciones durante el embarazo más frecuente el primer grupo 36.7 por ciento y 28.8 por ciento, predominando en ambos grupos la Ruptura Prematura de Membranas, seguida por la Anemia, Toxemia y Embarazo Prolongado. En la resolución del embarazo la Cesárea mostró una diferencia significativa entre ambos grupos con mayor frecuencia en el primero con 55.7 por ciento contra 34.4 por ciento (p<0.01) y la principal indicación de ésta fue la desproporción Cefalopélvica con 32.9 por ciento y 16.8 por ciento. En el peso de los productos sólo 5 por ciento y 6.5 por ciento fue subnormal, en el Apgar al minuto fue ligeramente bajo en el primer grupo, con dos óbitos preparto en el grupo dos. La Morbilidad Materna fue mayor en la jóvenes con 5 por ciento con tres 3 por ciento, minguna muerte materna. La morbilidad y mortalidad Perinatal fue 8.8 por ciento y 11.4 por ciento; predominando en ambos grupos el Retardo de Crecimiento intrauterino y en el grupo dos se presentaron dos Malformaciones Congénitas y dos Obitos Preparto. El Método Anticonceptivo usado fue el Dispositivo Intrauterino Post Parto con una frecuencia de 81 por ciento contra 72.2 por ciento. Se concluye que la Primigesta Adolescente se debe considerar de Alto Riesgo, ya que hay un incremento de la Morbilidad Materno Fetal, siendo más acentuada en las más jóvenes y que un control prental adecuado trae disminución de ésta