Disordered eating behaviors and experiences of violence among Mexican youth with different sexual orientations: A population-based study / Conductas alimentarias de riesgo y experiencias de violencia entre jóvenes mexicanos con diferentes orientaciones sexuales: Un estudio de base poblacional

Abstract Introduction In high-income countries, sexual minorities are at a higher risk for disordered eating behaviors. It is not known whether these findings can be extrapolated to Mexico. Objective Determine whether there are any differences in disordered eating behaviors among Mexican youth according to sexual orientation and analyze the potential role of experiences of violence and discrimination as mediators of these differences. Method Data from a representative sample of Mexican youth (12 to 29 years old, n = 27,876) were analyzed. Three groups were identified: young people who were not in love (NIL), who were in love with people of the opposite sex (ILOS), or in love with people of the same sex (ILSS). Restrictive behaviors, secret eating, and self-induced vomiting were identified through a scale created for the survey. Results ILSS men had a higher risk of restrictive thoughts and behaviors (B = .31), secret eating (OR = 2.21), and self-induced vomiting (OR = 3.65) than ILOS youth. Among women, there was only a difference in self-induced vomiting (RM = 2.49). In both sexes, being a young ILSS had an indirect effect on restrictive behaviors through its association with experiences of violence, discrimination at school, and sexual violence. Discussion and conclusion . Mexican sexual minority men are at a higher risk of disordered eating behaviors, whereas sexual minority women are at a higher risk of purging. Part of the differences in restrictive behaviors were explained by the increased risk for experiences of prejudice faced by sexual minority youth.

Resumen Introducción En países de alto ingreso, las minorías sexuales tienen mayor riesgo de conductas alimentarias de riesgo. Se desconoce si esos hallazgos pueden ser extrapolados a México. Objetivo Determinar si existen disparidades en las conductas alimentarias de riesgo entre los jóvenes mexicanos según la orientación sexual y analizar el papel potencial de las experiencias de violencia y discriminación como mediadoras de tales disparidades. Método Se analizaron datos de una muestra representativa de jóvenes mexicanos (12 a 29 años, n = 27,876). Se identificaron tres grupos: jóvenes sin enamoramiento (sE), con enamoramiento por personas del otro sexo (cEOS) o con enamoramiento por personas del mismo sexo (cEMS). Las conductas restrictivas, comer a escondidas e inducirse vómito se identificaron a través de una escala creada para la encuesta. Resultados Los hombres cEMS tuvieron mayor riesgo de pensamientos y comportamientos restrictivos (B = .31), comer a escondidas (RM = 2.21) e inducirse vómito (RM = 3.65) en comparación con los jóvenes cEOS. Entre las mujeres, solo hubo diferencia en inducirse vómito (RM = 2.49). En ambos sexos, ser un joven cEMS tuvo un efecto indirecto sobre las conductas restrictivas a través su asociación con experiencias de violencia y discriminación escolares y violencia sexual. Discusión y conclusión Los hombres de minorías sexuales mexicanas tienen mayor riesgo de conductas alimentarias de riesgo, y las mujeres de minorías sexuales tienen mayor riesgo de una conducta de tipo purgativo. Parte de las disparidades en conductas restrictivas se explicaron por el mayor riesgo de experiencias de prejuicio que enfrentan los jóvenes de minorías sexuales.

Evaluation of mental health and occupational stress in Mexican medical residents / Evaluación de la salud mental y el estrés laboral en médicos residentes mexicanos

Abstract Introduction Since mental health disorders are an emerging problem in medical residents, its detection and attention must be a priority. Objetive To compare the frequency of psychopathology in residents according to sociodemographic and clinical characteristics. Method We conducted a cross-sectional study evaluating the presence of psychopathology, as well as sociodemographic and clinical characteristics in 644 residents through online questionnaires. Results Among participants, 55.7% reported a psychiatric disorder at some point and 29.2% a current one; only 41.5% were under treatment. Additionally, 8.1% had attempted suicide, of which 32.4% attempted it during residency. We found that 6.5% of women and 3.3% of men presented "risk of psychopathology," with a higher percentage of men presenting "severe psychopathology." Individuals with "risk of psychopathology" presented significantly higher scores on all of the questionnaires, compared to those with "absence of psychopathology." Discussion and conclusion Residents with occupational stress also presented higher risks of psychopathology, suicide, and substance use. Being under psychiatric treatment significantly improved the scores on the different scales. Because residency is a period that may increase the probability of suffering psychopathology, interventions should be aimed at reducing occupational stress and bringing specialized care.

Resumen Introducción Dado que los trastornos de salud mental son un problema emergente en los médicos residentes, su detección y atención deben ser una prioridad. Objetivo Comparar la frecuencia de psicopatología en médicos residentes de acuerdo con las características clínicas y sociodemográficas. Método Realizamos un estudio transversal donde evaluamos la presencia de psicopatología, así como características clínicas y sociodemográficas en 644 médicos residentes por medio de cuestionarios en línea. Resultados Entre los participantes, el 55.7% reportó haber tenido un trastorno psiquiátrico en algún momento de su vida y el 29.2% al momento del estudio, de los cuales solo el 41.5% estaba bajo tratamiento psiquiátrico. Asimismo, el 8.1% había intentado suicidarse a lo largo de su vida y el 32.4% lo intentó durante la residencia. Encontramos que el 6.5% de las mujeres y el 3.3% de los hombres presentaban "riesgo de psicopatología", y un mayor porcentaje de hombres presentaron "psicopatología grave". Las personas con "riesgo de psicopatología" contaron con puntuaciones significativamente más altas en todos los cuestionarios, en comparación con los individuos con "ausencia de psicopatología". Discusión y conclusión Los residentes con estrés laboral también presentaron mayor riesgo de psicopatología, suicidio y uso de sustancias. Estar bajo tratamiento psiquiátrico mejoró significativamente los puntajes en las diferentes escalas. Debido a que la residencia es un período que puede aumentar la probabilidad de sufrir psicopatología, las intervenciones deben estar dirigidas a reducir el estrés ocupacional y brindar atención especializada.

Desarrollo embrionario-larval del pez tropical Hemirhamphus brasiliensis (Beloniformes: Hemirhamphidae) a partir de huevos recolectados del medio natural

Embrionary-larval development of the tropical fish Hemirhamphus brasiliensis (Beloniformes: Hemirhamphidae) from eggs collected in the wild. The embryo formation and larval development of Hemirhamphus brasiliensis Linnaeus, 1758 (Pisces: Hemirhamphidae) is described from morula stage eggs collected on Sargassum sp. Thalii in the field (10°50’55.2" N y 64°09’467" W). The eggs were spherical, 1 923.54 ±72.35 µm diameter with several corionic filaments, and are striated. During the first 48 h the embryo developed cephalic vesicle, miomers, and a heart located on the external body surface, beating strongly and circulating colorless blood which became pigmented red later. Before hatching, the larva developed kidney, gut tract, liver and biliar vesicle, pectoral fins, four pairs of gill arches and the mouth. The larva hatched at 114 h, the body was torpedo-shaped, yellow-green, with several dendriform melanophores; the pelvic fin was observed 72 h post hatching. At 240 hours the metamorphoses was completed. When the larvae hatched they could ingest Artemia metanauplii. Rev. Biol. Trop. 56 (3): 1449-1458. Epub 2008 September 30.

Se describe la formación del embrión y el desarrollo larval del pez Hemirhamphus brasiliensis Linnaeus, 1758, a partir de huevos en estado de mórula, recolectados en el alga parda Sargassum sp. Los huevos eran esféricos con un diámetro de 1923.54 ±72.35 µm, con numerosos filamentos coriónicos y estrías en su superficie. Durante las primeras 48 h, el embrión desarrolló la vesícula cefálica, los miomeros y el corazón, el cual se ubicó en el exterior de cuerpo impulsando sangre incolora, la cual se pigmentó de rojo posteriormente. Antes de la eclosión se desarrollaron el riñón, estómago, hígado y la vesícula biliar, las aletas pectorales, cuatro pares de arcos branquiales y la boca. Las larvas eclosionaron a la 114 h, presentando el cuerpo robusto en forma de torpedo, verde-amarillo con melanoforos dendriformes. Al nacer ingirieron metanauplios de Artemia. A las 72 h después de la eclosión se observó el esbozo de la aleta pélvica y a las 240 h se completó la metamorfosis.

[Embrionary-larval development of the tropical fish Hemirhamphus brasiliensis (Beloniformes: Hemirhamphidae) from eggs collected in the wild]. / Desarrollo embrionario-larval del pez tropical Hemirhamphus brasiliensis (Beloniformes: Hemirhamphidae) a partir de huevos recolectados del medio natural.

The embryo formation and larval development of Hemirhamphus brasiliensis Linnaeus, 1758 (Pisces: Hemirhamphidae) is described from morula stage eggs collected on Sargassum sp. Thalii in the field (10 degrees 50'55.2" N y 64 degrees 09'467" W). The eggs were spherical, 1 923.54 +/- 72.35 microm diameter with several corionic filaments, and are striated. During the first 48 h the embryo developed cephalic vesicle, miomers, and a heart located on the external body surface, beating strongly and circulating colorless blood which became pigmented red later. Before hatching, the larva developed kidney, gut tract, liver and biliar vesicle, pectoral fins, four pairs of gill arches and the mouth. The larva hatched at 114 h, the body was torpedo-shaped, yellow-green, with several dendriform melanophores; the pelvic fin was observed 72 h post hatching. At 240 hours the metamorphoses was completed. When the larvae hatched they could ingest Artemia metanauplii.

[Variation of the lipids and fatty acids in marine shrimps consumed in Venezuela]. / Variación de lípidos y ácidos grasos en camarones marinos consumidos en Venezuela.

There are three marine shrimp species in the Venezuelan internal market, two of them are native species, from fisheries, Farfantapenaeus brasiliensis and Litopenaeus schmitti, and one is an exotic species and farmed, L. vannamei. The objectives of this paper were to determine the possible variation of lipid content and fatty acid composition of these species, even under different culture conditions (e.g. feed used). The lipid content in all the species are higher (5 to 10 times) that the data from previous papers deal with marine shrimps, ranged from 4.8 to 10.9%, suggesting that its impact in the human health should be reviewed. At the same time, there were detected differences between the lipid content and fatty acids composition of the species. Wild L. schmitti had the highest lipid content (10.9%), following by wild F. brasiliensis (9.0%), cultured L. schmitti (4.8% to 7.1%) and cultured L. vannamei (5.1% to 6.2%). On the other hand, L. schmitti fed on commercial feed had the highest proportion of EPA and/or DHA, following by L. vannamei fed on the experimental feed, wild L. schmitti and fed with the experimental feed and wild F. brasiliensis.

Desarrollo embrionariolarval y tiempo de metamorfosis del pez tropical Xenomelaniris brasiliensis (Pisces: Atherinidae) / Development of the tropical fish Xenomelaniris brasiliensis (Pisces: Atherinidae) from embryo to larva and time to metamorphosis

Embryoniclarval development, and metamorphosis larval time, were studied in the tropical fish Xenomelaniris brasiliensis. Twenty nine sexually mature specimens were used, 16 females (10.86 ± 1.01 cm and 7.63 ± 2.62 g) and 13 males (10.43 ± 0.57 cm and 6.54 ± 1.44 g) which produced gametes through abdominal massage. Fertilized eggs were spherical (1.18 ± 0.44 mm diameter), greenish, transparent, benthonic and vitelusrich; rugose striated chorion with numerous external filaments randomly distributed and abundant oil globules (0.11 ± 0.07 mm diameter). The embryonic development was finished at 26.36 ± 2.03ºC, 39.67 ± 0.58 PSU and pH 8.30 ± 0.10. Larvae (4.56 ± 0.97 mm total length) hatched at 143 hours and 19 minutes, with vitteline sac vestiges and a single oil globule. The larvae were fed on Brachionus plicatilis and Isochrysis galbana. After the second week Artemia nauplii were added and I. galbana maintained. Flexion started 13 days after larvae hatched (6.10 ± 1.54 mm total length) and was completed 32 days later (11.25 ± 1.87 mm total length) with the hipural complex completely developed. In conclusion, X. brasiliensis showed direct larval development and started larval metamorphosis (13.08 ± 2.07 mm total length) to juvenile 40 days after hatching

Se describe el desarrollo embrionario y larval hasta la metamorfosis de Xenomelaniris brasiliensi. Un total de 29 ejemplares sexualmente maduros, 16 hembras (10.86 ± 1.01 cm y 7.63 ± 2.62 g) y 13 machos (10.43 ± 0.57 cm y 6.54 ± 1.44 g), liberaron sus productos sexuales mediante masaje abdominal. Los huevos fértiles fueron esféricos de 1.18 ± 0.44 mm de diámetro, verdosos, translúcidos, bentónicos, ricos en vitelo, corion rugoso y estriado, con numerosos filamentos coriónicos, distribuidos aleatoriamente por toda la superficie externa y numerosas gotas lipídicas con un diámetro de 0.11 ± 0.07 mm. El desarrollo embrionario se realizó a 26.36 ± 2.03 ºC, 39.67 ± 0.58 PSU y pH 8.30 ± 0.10 eclosionando larvas de 4.56 ± 0.97 mm a las 143 hrs: 19 min, con vestigios del saco vitelino y una gota lipídica interna. Las larvas fueron alimentadas diariamente con Brachionus plicatilis e Isochrysis galbana, a partir de la segunda semana se incorporó nauplios de Artemia, manteniendo la adición diaria de I. galbana. A los 13 días después de la eclosión de larvas (6.10 ± 1.54 mm) se inició la flexión, completándose a los 32 días (11.25 ± 1.87 mm) con un complejo hipural completamente desarrollado. Se concluye que X. brasiliensis presentó desarrollo larval directo, iniciándose la metamorfosis de larva (13.08 ± 2.07) a juvenil a los 40 días de edad

Variación de lípidos y ácidos grasos en camarones marinos consumidos en Venezuela / Variation of the lipids and fatty acids in marine shrimps consumed in Venezuela

En el mercado interno venezolano se consumen, fundamentalmente, tres especies de camarones marinos, dos autóctonas, encontradas en su ambiente natural, Farfantapenaeus brasiliensis y Litopenaeus schmitti, y una introducida y cultivada, L. vannamei. El objetivo del presente trabajo fue el de determinar, si existe variación en la proporción de lípidos y el perfíl de ácidos grasos de estas especies, incluso bajo diferentes condiciones de cultivo (balanceados utilizados). El total de lípidos detectado en todas las especies y condiciones de cultivo es mayor que el indicado en la bibliografía existente, superándolos en 5 a 10 veces, con valores que oscilan entre 4,8 y 10,9 por ciento, por lo que su incidencia en la salud debería ser revisada. Se evidenció una diferencia en el porcentaje de lípidos, así como en el perfíl de ácidos grasos de las especies. El mayor porcentaje de lípidos fue detectado en L. schmitti salvaje (10,9 por ciento) seguido de F. brasiliensis salvaje (9,0 por ciento),L. schmitti cultivado (4,8 por ciento a 7,1 por ciento) y L. vannamei cultivado (5,1 por ciento a 6,2 por ciento). De los camarones estudiados, L. schmitti cultivado con el balanceado comercial aparece con mayor proporción de EPA y/o DHA, seguido de L. vannamei alimentados con el balanceado experimental, L. schmitti salvaje y alimentado con el mismo balanceado y F. brasiliensis salvaje

[Development of the tropical fish Xenomelaniris brasiliensis (Pisces: Atherinidae) from embryo to larva and time to metamorphosis]. / Desarrollo embrionario-larval y tiempo de metamorfosis del pez tropical Xenomelaniris brasiliensis (Pisces: Atherinidae).

Embryonic-larval development, and metamorphosis larval time, were studied in the tropical fish Xenomelaniris brasiliensis. Twenty nine sexually mature specimens were used, 16 females (10.86+/-1.01 cm and 7.63+/-2.62 g) and 13 males (10.43+/-0.57 cm and 6.54+/-1.44 g) which produced gametes through abdominal massage. Fertilized eggs were spherical (1.18 +/-0.44 mm diameter), greenish, transparent, benthonic and vitelus-rich; rugose striated chorion with numerous external filaments randomly distributed and abundant oil globules (0.11 + 0.07 mm diameter). The embryonic development was finished at 26.36+/-2.03 degrees C, 39.67+/-0.58 PSU and pH 8.30+/-0.10. Larvae (4.56+/-0.97 mm total length) hatched at 143 hours and 19 minutes. with vitteline sac vestiges and a single oil globule. The larvae were fed on Brachionus plicatilis and Isochrysis galbana. After the second week .4rtemia nauplii were added and I. galbana maintained. Flexion started 13 days after larvae hatched (6.10+/-1.54 mm total length) and was completed 32 days later (11.25+/-1.87 mm total length) with the hipural complex completely developed. In conclusion, X brasiliensis showed direct larval development and started larval metamorphosis (13.08+/-2.07 mm total length) to juvenile 40 days after hatching.

[Larval survival and growth of Arbacia punctulata (Echinodermata: Echinoidea) fed with five micro-algae at two salinities]. / Supervivencia y crecimiento larval de Arbacia punctulata (Echinodermata: Echinoidea) alimentada con cinco microalgas a dos salinidades.

Fertilized eggs from an spontaneously spawn of thirty sexually mature sea urchins (Arbacia punctulata) were incubated to complete embryonic development. The echinopluteus larvae (3 ind/ml) were distributed into 50 plastic containers (25 containers at 30 psu and 25 containers at 40 psu) and fed on Tetraselmis chuii, Nannochloropsis oculata, Isochrysis galbana, Chaetoceros gracilis and C. calcitrans under a natural photoperiod. The water of the containers was partially renewed (75%) everyday. Larval anatomic development aspects, daily survival and growth were determined. The growth was determined through postoral arms and body length measurement, and body diameter of twelve larvae during metamorphosis. During the planktonic larval phase, only the I. galbana diet produced similar results for both salinities. The relative growth of larvae was isometric (I) for larvae fed on I. galbana at two salinities and positive allometric for those fed on C. gracilis and C. calcitrans at both salinities. In this study A. punctulata started metamorphosis at day 14 and was completed 30 days after fecundation. Significant differences were detected in post-settlement body growth between the two salinities (F = 23.58, p < 0.05): growth was better for larvae at 30 psu (final body diameter was 3.14 +/- 0.44 mm). The final rate of planktonic larvae was highest with I. galbana (58.33%). For juveniles the rate was 6.48% for those fed on C. gracilis (40 psu in both larvae and juveniles). We recommend the use of this diet and 40 psu for survival or 30 psu for growth.

[Larval growth and survival of Echinometra lucunter (Echinoidea: Echinometridae) fed with microalgae Chaetoceros gracilis and Isochrysis galbana]. / Crecimiento y supervivencia de larvas de Echinometra lucunter (Echinoidea: Echinometridae) alimentadas con las microalgas Chaetoceros gracilis e Isochrysis galbana.

Thirty sexually mature sea urchins (Echinometra lucunter; diameter 45.8 +/- 17.5 mm) were collected at Macanao, Margarita Island, Venezuela (11 degrees 48'29" N / 64 degrees 13'10" W). They were injected potassium chloride (50 M) directly into the celomic cavity. After two minutes 90% spawned (17 females and 10 males), the others never spawned. Fertilization was 87.0 +/- 12.6% (1:100 oocytes/sperm) at 29 +/- 2 degrees C. The fertile eggs were placed in three treatment gropsu with nine containers (18 liters; 2 eggs/ml) each, all with bottom aeration. Treatments were: Chaetoceros gracilis; Isochrysis galbana, and a mixture of both microalgae (respectively: 20 000 and 60,000 cell/ml for each microalgae, 1:1 for the mixture). Salinity, pH, temperature and larval survival were determinated daily. The study ended when the post-metamorphic phase was completed. The embryonic development time was 16.3 +/- 0.2 h until the prism stage at pH 8.4 +/- 0.1; 38 +/- 1 psu and 28 +/- 1.4 degrees C. The two-arms larval stage was reached at 24 h: 33 min, with a total length of 190 +/- 16.3 microm fed on C. gracilis, 152 +/- 19.0 microm with I. galbana and 182.4 +/- 14.1 microm with the mixture. The larvae next to metamorphosis reabsorbed the arms and had the characteristic shape of juvenile urchins at 12 days with 670.2 +/- 22.2 microm fed on C. gracilis, 665 +/- 12.1 microm fed on I. galbana and 670 +/- 14.1 microm fed on the mixture. The accumulated survival to the juvenile stage was 14.7 +/- 3.8% when fed on C. gracilis, higher than the other treatments (5.4 +/- 1.2; 14.0 +/- 2.6). E. lucunter is an excellent prospect to be commercially cultured because of its short embryonic (16 hours) and larval development time (12 days) and good survival rate when fed on monoculture (C. gracilis and I. galbana) or mixed diet (we recommend C. gracilis).

Condiciones sedimentológicas de la laguna La Restinga, Isla de Margarita, Venezuela / Sedimentology conditions of the La Restinga lagoon, Margarita Island, Venezuela

La laguna La Restinga, en el sureste del Mar Caribe, es una laguna costera que comprende pequeñas lagunas rodeadas de manglares, conformando el sistema lagunar más importante de la Isla de Margarita. Se comunica con el mar, al sur, a través de una boca de 800m de largo, 80-100m de ancho y profundidad promedio de 6m. Está separada del mar, al norte, por un istmo o restinga de 23,5km, y sus drenajes naturales se evidencian solamente en la época de lluvia. Se estudiaron algunos aspectos de la sedimentología de este sistema lagunar determinándose la distribución espacial de sedimentos y algunas de sus características químicas. En febrero de 1994 se extrajeron 31 muestras de sedimentos superficiales, 25 en la laguna y 6 en el mar adyacente a la boca, mediante una draga Ekman, y se preservaron a 10ºC, realizándoseles análisis granulométrico y químico. Se determinó un fondo lagunar areno limoso. La materia orgánica y el contenido hídrico, en la laguna, estuvieron asociados al sedimento de textura fina y se localizaron en las áreas más amplias, someras y protegidas por cinturones de manglares, donde las corrientes de fondo fueron escasas o nulas (baja energía cinética media). El alto porcentaje de carbonato de calcio estuvo asociado con la fracción gruesa del sedimento y se localizó en la boca y los caños que interconectan las sublagunas internas, donde las corrientes de fondo son rápidas (alta energía cinética media). El grado de escogimiento del sedimento fue muy pobre y la distribución de la agudeza gráfica fue generalmente aguda y muy aguda, dependiendo de las diferentes fracciones encontradas en el sedimento