Acute and sub-acute toxicity study of ethanol extract from Nectandra leucantha Nees & Mart. (Lauraceae) barks.

Nectandra leucantha has been used in traditional medicine. Several metabolites isolated from N. leucantha extracts displayed immunomodulatory, antileishmanial properties, but the determination of the toxicological profile in mammals has not previously been performed. In this study, the ethanol extract from N. leucantha barks (EENl) was characterized by HPLC/HRESIMS. To study acute toxicity, female mice received EENl in a single dose of 100, 300, 1000, or 2000 mg/kg bw. Later, sub-acute toxicity was introduced in female and male mice by oral gavage at 100, 500 or 1000 mg/kg bw for 28 consecutive days. Hematological and biochemical profiles from the blood as well as histological analysis from the liver and kidney were performed. The HPLC/HRESIMS analysis of the EENl revealed the presence of six neolignans chemically related to dehydrodieugenol B. In the oral acute and sub-chronic studies, EENl did not produce in all doses evaluated any alteration in behavior, biochemical, hematological, body weight gain and food intake or sudden death in Swiss mice. In addition, histopathological data did not reveal any disturbance in liver and kidney morphology after 28 days of EENl treatment. Our results indicate that EENl at dosage levels up to 2000 mg/kg bw is non-toxic and can be considered safe for mammals.

Experimental evidence of masculinization by continuous illumination in a temperature sex determination teleost (Atherinopsidae) model: is oxidative stress involved?

The present study evaluates the influence of continuous light on phenotypic sex ratios in Chirostoma estor, a temperature sex determination animal model. Relative gene expression levels of 5 day old larvae were performed on two early gonad differentiation genes (sox9 and foxl2), two stress axis activation genes (gcr1 and crf) and four reactive oxygen species (ROS) antagonist effector genes (sod2, ucp2, gsr and cat). Two light treatments were applied from fertilization; control (12L:12D) simulated natural photoperiod and a continuous illumination photoperiod. By the end of the trial (12 weeks after hatching), differentiated and normal gonads were clearly identifiable in both treatments by histological observations. Regarding sex ratio, 73% of phenotypic males were found in continuous illumination compared with 40% in controls. Consistently, the sox9 gene (involved in early testis differentiation) showed an over expression in 64% of the individual larvae analysed compared with foxl2 (ovarian differentiation) suggesting a masculinization tendency in continuous illumination. On the other hand, only 36% of individuals showed the same tendency in the control treatment consistent with phenotypic sex ratios found under normal culture conditions. Relative gene expression results did not show significant difference in sod2, ucp2 and gcr1 levels, but cat, gsr and crf showed significantly higher expression levels in the continuous illumination treatment suggesting that both, the stress axis and ROS response mechanisms were activated at this time. This study suggests, a link between continuous light, oxidative stress and environmental sex determination in vertebrates. However, further research is necessary to describe this possible upstream mechanism that may drive some aspects of sexual plasticity in vertebrates.

3,5-Diiodothyronine (T2) is on a role. A new hormone in search of recognition.

Thyroid hormone (TH) actions are mediated by triiodothyronine (T3), which acts by binding to the TH receptors (TRs). Since TH exert pleiotropic effects, interest has grown in identifying other possible bioactive thyronines that could explain their diversity of functions. Accordingly, 3,5-diiodothyronine (T2) has been shown to be bioactive. In mammals, T2 regulates mRNA expression of several T3-regulated genes, but doses up to 100-fold greater than those of T3 were required to generate comparable effects. In teleosts, T2 and T3 regulate gene expression in vivo with equivalent potency. Furthermore, in vivo and in vitro studies support the notion that T2 binds to and activates a specific, long TRß1 isoform that contains a nine amino acid insert at the beginning of the ligand binding domain, whereas T3 can interact also with a different TRß1 isoform that lacks this insert. Similarly, T2 and T3 differentially regulate long- and short-TRß1 expression, respectively, strongly suggesting a different signaling pathway for each hormone, at least in the species that express both receptors. In vivo, T2 effectively triggers a burst of body growth in tilapia by interacting with the long TRß1 isoform, supporting the notion that T2 is physiologically relevant in this species. Current knowledge of T2 effects and action mechanisms lead us to propose that there is an extra level in the thyroid hormone signaling cascade, and that T2 is produced and regulated specifically for this purpose.

Shining light on the transcriptome: Molecular regulatory networks leading to a fast-growth phenotype by continuous light in an environmentally sensitive teleost (Atherinopsidae).

Photoperiod can profoundly affect the physiology of teleost fish, including accelerated growth here defined as "fast growth phenotypes". However, molecular regulatory networks (MRNs) and biological processes being affected by continuous illumination and which allow some teleost species evident plasticity to thrive under this condition are not yet clear. Therefore, to provide a broad perspective of such mechanisms, Chirostoma estor fish were raised and sampled for growth under a simulated control (LD) 12 h Light: 12 h Dark or a continuous illumination (LL) 24 h Light: 0 h Dark since fertilization. The experiment lasted 12 weeks after hatching (wah), the time at which fish were sampled for growth, length, and whole-body cortisol levels. Additionally, 3 heads of fish from each treatment were used to perform a de novo transcriptome analysis using Next-Generation Sequencing. Fish in LL developed the fast growth phenotype with significant differences visible at 4 wah and gained 66% more mass by 12 wah than LD fish. Cortisol levels under LL were below basal levels at all times compared to fish in LD, suggesting circadian dysregulation effects. A strong effect of LL was observed in samples with a generalized down-regulation of genes except for Reactive Oxygen Species responses, genome stability, and growth biological processes. To our knowledge, this work is the first study using a transcriptomic approach to understand environmentally sensitive MRNs that mediate phenotypic plasticity in fish submitted to continuous illumination. This study gives new insights into the plasticity mechanisms of teleost fish under constant illumination.

Loss of gut microbial diversity in the cultured, agastric fish, Mexican pike silverside (Chirostoma estor: Atherinopsidae).

Teleost fish are the most diverse group of extant vertebrates and have varied digestive anatomical structures and strategies, suggesting they also possess an array of different host-microbiota interactions. Differences in fish gut microbiota have been shown to affect host development, the process of gut colonization, and the outcomes of gene-environment or immune system-microbiota interactions. There is generally a lack of studies on the digestive mechanisms and microbiota of agastric short-intestine fish however, meaning that we do not understand how changes in gut microbial diversity might influence the health of these types of fish. To help fill these gaps in knowledge, we decided to study the Mexican pike silverside (Chirostoma estor) which has a simplified alimentary canal (agastric, short-intestine, 0.7 gut relative length) to observe the diversity and metabolic potential of its intestinal microbiota. We characterized gut microbial populations using high-throughput sequencing of the V3 region in bacterial 16S rRNA genes while searching for population shifts resulting associated with fish development in different environments and cultivation methods. Microbiota samples were taken from the digesta, anterior and posterior intestine (the three different intestinal components) of fish that grew wild in a lake, that were cultivated in indoor tanks, or that were raised in outdoor ponds. Gut microbial diversity was significantly higher in wild fish than in cultivated fish, suggesting a loss of diversity when fish are raised in controlled environments. The most abundant phyla observed in these experiments were Firmicutes and Proteobacteria, particularly of the genera Mycoplasma, Staphylococcus, Spiroplasma, and Aeromonas. Of the 14,161 OTUs observed in this experiment, 133 were found in all groups, and 17 of these, belonging to Acinetobacter, Aeromonas, Pseudomonas, and Spiroplasma genera, were found in all samples suggesting the existence of a core C. estor microbiome. Functional metagenomic prediction of bacterial ecological functions using PICRUSt2 suggested that different intestinal components select for functionally distinct microbial populations with variation in pathways related to the metabolism of amino acids, vitamins, cofactors, and energy. Our results provide, for the first time, information on the bacterial populations present in an agastric, short-gut teleost with commercial potential and show that controlled cultivation of this fish reduces the diversity of its intestinal microbiota.

A segmental osteotomy with 3D virtual planning to move a malpositioned dental implant.

BACKGROUND: Correct positioning and alignment of dental implants are crucial to successfully meet the aesthetic and functional criteria in implant-prosthetic rehabilitation. When an implant is in the wrong position, especially in the esthetical zone, there are limited options to solve it. Some techniques have been described to reposition implants, such as reverse torque, trephine drills, and segmental osteotomies; current approaches aim to reduce the damage of the periimplant tissues. CASE PRESENTATION: A 20-year-old man with good general health was referred to the oral and maxillofacial surgery department of the CES University, Medellin Colombia in 2017, He had undergone a previous camouflage orthodontic therapy for a dental Class III, which finished in 2014, posteriorly a dental implant was placed in 2015 to replace upper right lateral incisor (1.2) before vertical growth of maxilla was complete; therefore, the implant was retained in a coronal position. A segmental osteotomy was suggested to reposition the implant in a more caudal position, a 3D surgical cut guide obtained by virtual planning was used to increase osteotomy accuracy and lower human error, to avoid the risk of damaging the adjacent tissues and to achieve a predictable result. CONCLUSIONS: The segmental alveolar osteotomy is an effective alternative to reposition an implant; however, it must be carefully planned because human error remains a possibility that may affect the final result. Therefore, 3D planning is a better way to minimize these mistakes during the surgical procedure and the final position of the implant.

Myopericarditis Complicated With Cardiac Tamponade Due to Campylobacter fetus Infection.

About 90% of cases of acute pericarditis have an idiopathic or viral etiology. In some cases, it is possible to identify high-risk patients for whom hospital admission and specific etiology research are mandatory for adequate treatment. Bacterial pericarditis is uncommon and responsible for less than 1% of cases. Only 10 cases of pericarditis due to Campylobacter fetus have been documented worldwide. This case highlights the importance of good cardiac imaging, with the right clinical and microbiology-integrated approach in high-risk cases of pericardial disease.

Environ 90 % des cas de péricardite aiguë sont d'étiologie idiopathique ou virale. Dans certains cas, il est possible de déterminer les patients exposés à un risque élevé pour qui l'admission à l'hôpital et la recherche d'une étiologie précise sont indispensables pour offrir le bon traitement. La péricardite bactérienne est rare et représente moins de 1 % des cas. Seuls 10 cas de péricardite à Campylobacter fetus ont été consignés dans le monde. Ce cas illustre l'importance d'une bonne imagerie cardiaque selon une bonne approche clinique et microbiologique intégrée chez les cas exposés à un risque élevé de maladies péricardiques.

Drop-off in positivity rate of stress echocardiography based on regional wall motion abnormalities over the last three decades.

Previous studies have suggested a decline in positivity of stress cardiac imaging based on regional wall motion abnormalities (RWMA). To assess the rate of RWMA positivity of stress echocardiography (SE) over 3 decades in the same primary care SE lab. We retrospectively assessed the rate of SE positivity in 7626 SE tests (dipyridamole in 5053, dobutamine in 2496, exercise in 77) in consecutive patients with known or suspected coronary artery disease and /or heart failure who performed SE in a primary care referral center from April 1991 to May 2018. Starting April 2005, SE based on RWMA was complemented by assessment of coronary flow velocity reserve (CFVR) of the left anterior descending coronary artery. Starting October 2016, we added left ventricular contractile reserve (LVCR). Starting October 2016, we also added B-lines by lung ultrasound. There was a progressive decline over time in the rate of SE positivity based on RWMA from 24% (1991-1999) to 10% (2000-2009) down to 4% (2010-2018) (p < 0.0001). Positivity rate was 29% with CFVR, 16% with LVCR, and 12% with B-lines. Over three decades, we observed a dramatic decline in SE positivity rate based on classical RWMA. In the last decade, the positivity rate rose sharply thanks to the stepwise introduction of CFVR, LVCR and B-lines as additional positivity criteria in integrated quadruple SE.

Revisión sistemática del compromiso escolar en educación secundaria / A systematic review of methodological aspects of student engagement research in secondary students

Resumen La investigación sobre el compromiso escolar de los estudiantes ha crecido significativamente en la última década y su medición es de gran interés en la investigación educativa. Esto se podría explicar por su potencial para comprender problemas educativos importantes con respecto a las trayectorias académicas de los estudiantes, incluida la adaptación a la escuela, el rendimiento y los logros académicos, las tasas de finalización y la deserción escolar. Se ha evidenciado que los estudiantes que se sienten más comprometidos con su escuela experimentan una trayectoria escolar más positiva y tienen una vida más exitosa, por lo que se considera que el compromiso escolar es una variable protectora vinculada a tasas más bajas de delincuencia, abuso de sustancias y depresión. Para obtener una comprensión más profunda del cuerpo de investigación actual sobre el compromiso escolar de los estudiantes, esta revisión de la literatura tuvo por objetivo analizar las características metodológicas de la investigación empírica cuantitativa sobre ese compromiso de los estudiantes en la escuela secundaria. Como método se realizó una revisión sistemática de la literatura en las bases de datos Web of Science, Scopus y SciELO del período 2013 a 2020. Cuarenta y siete artículos cumplieron los criterios de inclusión establecidos. Los resultados evidenciaron que casi todos los estudios se realizaron en Estados Unidos, mientras que ninguno de los artículos analizados fue desarrollado en América Latina. Con respecto al tamaño de la muestra, se identificó que la mayoría de los estudios revisados ​​tenían un tamaño de muestra entre 501 y 5000 participantes. En cuanto a los diseños de investigación utilizados en estos estudios, la mayoría utilizó un diseño correlacional, pero solo unos pocos implementaron diseños longitudinales o cuasi experimentales. Se identificó la coexistencia de diferentes marcos conceptuales sobre el compromiso escolar; sin embargo, la investigación concuerda en comprenderlo como un constructo multidimensional que implica el involucramiento del estudiante en actividades relacionadas con la escuela y su estudio. La diversidad conceptual del constructo de compromiso escolar se refleja en los numerosos instrumentos identificados en esta revisión, en los que las dimensiones más prevalentes del compromiso escolar fueron la dimensión conductual, cognitiva y emocional. Respecto de los tipos de variables incluidas en los estudios de compromiso escolar, se observó que se han incluido un gran número que cubren diferentes aspectos y temas relacionados con las experiencias académicas de los estudiantes, como las relacionadas con los propios estudiantes, así como las relacionadas con los padres, compañeros, profesores y escuelas. En conclusión, dado que el compromiso escolar de los estudiantes es una variable que se ha considerado crítica en contextos académicos, a medida que se realicen estudios futuros en este campo, será importante examinar la correlación de diferentes tipos de variables con el compromiso escolar de los estudiantes. Se podrían examinar las potenciales variables moderadoras que podrían surgir al realizar estudios en nuevos entornos educativos o culturalmente diversos, por ejemplo, con estudiantes con necesidades especiales. Esto es especialmente importante cuando se considera a la región Latinoamericana. Dado que la mayoría de los estudios se han realizado en Estados Unidos, se requiere considerar aspectos importantes antes de su implementación, como la validez de los instrumentos de medida, los que podrían estar sesgados si no se adaptan a la cultura Latinoamericana. Además, los estudios futuros deberían definir con precisión el constructo de compromiso escolar de los estudiantes y lograr un consenso en la investigación.

Abstract Student engagement research has grown significantly in the past decade and measuring it is of high interest in educational research. To gain a deeper understanding of the current body of research on student engagement, this review aims to analyze the design characteristics of empirical quantitative research on student engagement in secondary school. A systematic review was performed in the Web of Science, Scopus, and SciELO databases from the period 2013 to 2020. Forty-seven articles met the inclusion criteria. The results revealed that most studies were performed in North America and none in Latin America; the designs were mainly measuring variable associations. Teacher-related variables are the least examined variables. The instruments used to measure the student engagement and the constructs employed, shows there is substantial theoretical heterogeneity among studies. Future studies need to accurately define student engagement; give further attention to variables related to teachers, peers, families, and institutional conditions.

Effect of dietary protein: lipid ratio on growth and body composition in bullfrog (Lithobates catesbeianus)

A feeding trial was performed to assess dietary protein:lipid ratios for the grow-out phase of the bullfrog (Lithobates catesbeianus). Nine balanced isoenergetic diets were formulated, combining three different protein levels (300, 400, and 500 g kg−1) with three different lipid levels (50, 100, and 200 g kg−1), designated as P300/50L, P300/100L, P300/200L, P400/50L, P400/100L, P400/200L, P500/50L, P500/100L, and P500/200L. Additionally, a commercial fish feed, commonly used in Mexico to feed bullfrogs, was also tested during the experiment. Growth performance, animal performance parameters, carcass composition, and fatty acid profiles in muscle and liver were evaluated. The feeding trial results showed that all the experimental diets enhanced growth, feed conversion ratio, and frog-leg weight compared with the commercial diet. Bullfrogs had higher growth with 400 and 500 g kg−1 of dietary protein regardless of dietary lipid content. It was also notable that with the P500/200L diet, frogs doubled the weight of those fed the commercial diet. DHA, EPA, and total omega-3 fatty acids were double in muscle and two to eight times higher in the liver compared with the commercial diet. In all cases, the final proximal composition of carcass reflected the diet composition. It is suggested that a diet containing 400 g kg−1 of protein and 50 g kg−1 lipids (protein/lipid ratio: 7.4; gross energy: 18.2 MJ kg−1) is adequate for bullfrog performance during the grow-out phase to achieve market size in a shorter period, thus, reducing farming risks and production costs.

Assurance of Myeloid Growth Factor Administration in an Infusion Center: Pilot Quality Improvement Initiative.

PURPOSE: Four incident reports involving missed doses of myeloid growth factors (MGFs) triggered the need for an outcome-driven initiative. From March 1, 2015, to February 29, 2016, at University of California Irvine Health Chao Infusion Center, 116 of 3,300 MGF doses were missed (3.52%), including pegfilgrastim, filgrastim, and sargramostim. We hypothesized that with the application of Lean Six Sigma methodology, we would achieve our primary objective of reducing the number of missed MGF doses to < 0.5%. METHODS: This quality improvement initiative was conducted at Chao Infusion Center as part of a Lean Six Sigma Green Belt Certification Program. Therefore, Lean Six Sigma principles and tools were used throughout each phase of the project. Retrospective and prospective medical record reviews and data analyses were performed to evaluate the extent of the identified problem and impact of the process changes. Improvements included systems applications, practice changes, process modifications, and safety-net procedures. RESULTS: Preintervention, 24 missed doses (20.7%) required patient supportive care measures, resulting in increased hospital costs and decreased quality of care. Postintervention, from June 8, 2016, to August 7, 2016, zero of 489 MGF doses were missed after 2 months of intervention ( P < .001). Chao Infusion Center reduced missed doses from 3.52% to 0%, reaching the goal of < 0.5%. CONCLUSION: The establishment of simplified and standardized processes with safety checks for error prevention increased quality of care. Lean Six Sigma methodology can be applied by other institutions to produce positive outcomes and implement similar practice changes.

Effects of continuous light and light intensity on the growth performance and gonadal development of Nile tilapia

Continuous illumination has been known to exert positive effects by stimulating growth and delaying unwanted maturation in seasonal-temperate farmed fish species like salmonids. However, in tropical fish like Nile tilapia (Oreochromis niloticus), some studies exist showing inconsistent results and even fewer data is available regarding the effects of light intensity. To clarify some of the inconsistent results in literature and evaluate the effect of different light intensity levels on growth and sexual maturation in Nile tilapia (Oreochromis niloticus), we reared twenty days post-hatch Nile tilapia larvae under continuous illumination at three different light intensities and compared against a control photoperiod (12L:12D) up to 118 days post-hatch. A total of 600 fry were used using 75 fry per experimental unit in a previously tested experimental aquarium setup. Fish exposed to high and medium intensity continuous illumination treatments were significantly heavier (13-20%) and longer (6-8%) than fish exposed to the control photoperiod. Importantly, however, the degree of growth enhancement did not vary significantly according to the light intensity used. Feed intake was also higher in all continuous illumination treatments than in the control photoperiod, suggesting that growth benefits might be due to an increase in feed intake, which is not affected by the light intensities used. Gonadal development on the other hand, presented differences between sexes with a delay in spermatogenesis, while an advancement towards ovarian maturation occurred compared with the control fish. These results suggest that continuous illumination can influence both growth and gonadal development in Nile tilapia with no apparent differences between the light intensities tested in this study.

3,5-Diiodothyronine-mediated transrepression of the thyroid hormone receptor beta gene in tilapia. Insights on cross-talk between the thyroid hormone and cortisol signaling pathways.

T3 and cortisol activate or repress gene expression in virtually every vertebrate cell mainly by interacting with their nuclear hormone receptors. In contrast to the mechanisms for hormone gene activation, the mechanisms involved in gene repression remain elusive. In teleosts, the thyroid hormone receptor beta gene or thrb produces two isoforms of TRß1 that differ by nine amino acids in the ligand-binding domain of the long-TRß1, whereas the short-TRß1 lacks the insert. Previous reports have shown that the genomic effects exerted by 3,5-T2, a product of T3 outer-ring deiodination, are mediated by the long-TRß1. Furthermore, 3,5-T2 and T3 down-regulate the expression of long-TRß1 and short-TRß1, respectively. In contrast, cortisol has been shown to up-regulate the expression of thrb. To understand the molecular mechanisms for thrb modulation by thyroid hormones and cortisol, we used an in silico approach to identify thyroid- and cortisol-response elements within the proximal promoter of thrb from tilapia. We then characterized the identified response elements by EMSA and correlated our observations with the effects of THs and cortisol upon expression of thrb in tilapia. Our data show that 3,5-T2 represses thrb expression and impairs its up-regulation by cortisol possibly through a transrepression mechanism. We propose that for thrb down-regulation, ligands other than T3 are required to orchestrate the pleiotropic effects of thyroid hormones in vertebrates.

High levels of docosahexaenoic acid are present in eight New World silversides (Pisces: Atherinopsidae)

Docosahexaenoic acid (DHA) is the most critical and least available omega-3 fatty acid in the Western human diet. Currently, the source of omega-3 long chain polyunsaturated fatty acids (LC-PUFA) is mainly dependent on wild fisheries, making this resource unsustainable in the foreseeable future. In recent years, a high rate of biosynthesis and accumulation of DHA has been discovered in a freshwater species (Chirostoma estor) belonging to the Atherinopsidae family. Interest in evaluating fatty acid composition in other members of the family has emerged, so this study compiles original data of flesh composition of eight atherinopsid species from freshwater and brackish environments, either wild or cultured. High levels of DHA (16 to 31%) were found in all analyzed members of the family, except in C. grandocule, independently of their habitat or origin. The analyzed species of the Jordani group (C. estor, C. promelas and C. humboldtianum) showed high DHA and low EPA levels (<0.5%) as previously reported for cultured C. estor. The low trophic niche of these atherinopsids and their fatty acid accumulation capabilities are factors that make these species noteworthy candidates for sustainable aquaculture.(AU)

O ácido docosahexaenóico (DHA) é o ácido graxo ômega-3 mais importante e menos disponível na dieta humana ocidental. Atualmente, a fonte de ácidos graxos poliinsaturados de cadeia longa ômega-3 (LC-PUFA) depende principalmente da pesca extrativista, tornando esse recurso insustentável em um futuro próximo. Nos últimos anos, uma alta taxa de biossíntese e acúmulo de DHA foi descoberta em uma espécie de água doce (Chirostoma estor) pertencente à família Atherinopsidae. Deste modo, surgiu o interesse em avaliar a composição de ácidos graxos em outros membros da família. Portanto, este estudo compila dados originais da composição de carne de oito espécies de aterinopsídeos de ambientes de água doce e salobra, selvagens ou cultivadas. Altos níveis de DHA (16 a 31%) foram encontrados em todos os membros da família analisados, exceto em C. grandocule, independentemente de seu habitat ou origem. As espécies analisadas do grupo Jordani (C. estor, C. promelas e C. humboldtianum) apresentaram altos níveis de DHA e EPA baixos (<0,5%), como relatado anteriormente para C. estor cultivado. O baixo nicho trófico desses aterinopsídeos e sua capacidade de acumulação de ácidos graxos são fatores que tornam essas espécies notáveis candidatas à aquicultura sustentável.(AU)

High levels of docosahexaenoic acid are present in eight New World silversides (Pisces: Atherinopsidae)

ABSTRACT Docosahexaenoic acid (DHA) is the most critical and least available omega-3 fatty acid in the Western human diet. Currently, the source of omega-3 long chain polyunsaturated fatty acids (LC-PUFA) is mainly dependent on wild fisheries, making this resource unsustainable in the foreseeable future. In recent years, a high rate of biosynthesis and accumulation of DHA has been discovered in a freshwater species (Chirostoma estor) belonging to the Atherinopsidae family. Interest in evaluating fatty acid composition in other members of the family has emerged, so this study compiles original data of flesh composition of eight atherinopsid species from freshwater and brackish environments, either wild or cultured. High levels of DHA (16 to 31%) were found in all analyzed members of the family, except in C. grandocule, independently of their habitat or origin. The analyzed species of the Jordani group (C. estor, C. promelas and C. humboldtianum) showed high DHA and low EPA levels ( 0.5%) as previously reported for cultured C. estor. The low trophic niche of these atherinopsids and their fatty acid accumulation capabilities are factors that make these species noteworthy candidates for sustainable aquaculture.

RESUMO O ácido docosahexaenóico (DHA) é o ácido graxo ômega-3 mais importante e menos disponível na dieta humana ocidental. Atualmente, a fonte de ácidos graxos poliinsaturados de cadeia longa ômega-3 (LC-PUFA) depende principalmente da pesca extrativista, tornando esse recurso insustentável em um futuro próximo. Nos últimos anos, uma alta taxa de biossíntese e acúmulo de DHA foi descoberta em uma espécie de água doce (Chirostoma estor) pertencente à família Atherinopsidae. Deste modo, surgiu o interesse em avaliar a composição de ácidos graxos em outros membros da família. Portanto, este estudo compila dados originais da composição de carne de oito espécies de aterinopsídeos de ambientes de água doce e salobra, selvagens ou cultivadas. Altos níveis de DHA (16 a 31%) foram encontrados em todos os membros da família analisados, exceto em C. grandocule, independentemente de seu habitat ou origem. As espécies analisadas do grupo Jordani (C. estor, C. promelas e C. humboldtianum) apresentaram altos níveis de DHA e EPA baixos ( 0,5%), como relatado anteriormente para C. estor cultivado. O baixo nicho trófico desses aterinopsídeos e sua capacidade de acumulação de ácidos graxos são fatores que tornam essas espécies notáveis candidatas à aquicultura sustentável.

3,5-di-iodothyronine stimulates tilapia growth through an alternate isoform of thyroid hormone receptor ß1.

Recent studies in our laboratory have shown that in some teleosts, 3,5-di-iodothyronine (T2 or 3,5-T2) is as bioactive as 3,5,3'-tri-iodothyronine (T3) and that its effects are in part mediated by a TRß1 (THRB) isoform that contains a 9-amino acid insert in its ligand-binding domain (long TRß1 (L-TRß1)), whereas T3 binds preferentially to a short TRß1 (S-TRß1) isoform that lacks this insert. To further understand the functional relevance of T2 bioactivity and its mechanism of action, we used in vivo and ex vivo (organotypic liver cultures) approaches and analyzed whether T3 and T2 differentially regulate the S-TRß1 and L-TRß1s during a physiological demand such as growth. In vivo, T3 and T2 treatment induced body weight gain in tilapia. The expression of L-TRß1 and S-TRß1 was specifically regulated by T2 and T3 respectively both in vivo and ex vivo. The TR antagonist 1-850 effectively blocked thyroid hormone-dependent gene expression; however, T3 or T2 reversed 1-850 effects only on S-TRß1 or L-TRß1 expression, respectively. Together, our results support the notion that both T3 and T2 participate in the growth process; however, their effects are mediated by different, specific TRß1 isoforms.

Identidad sexual en jóvenes gay del norte de Chile / The sexual identity of gay youths in Northern Chile / Identidade sexual em jovens gay do norte do Chile

Resumen La investigación en la que se funda este artículo tuvo como objetivo comprender cómo se construye la identidad sexual en hombres gay jóvenes, entre 18 y 29 años de edad, de la ciudad de Antofagasta, en el norte de Chile. El enfoque de la investigación fue cualitativo y la selección de los participantes fue de carácter intencional. La técnica de producción de información fue la entrevista semi-estructurada. Se identificaron tres categorías que inciden en la construcción de la identidad sexual de los jóvenes entrevistados: a) la socialización de género; b) la discriminación; y c) la "salida del armario" (revelación de la orientación sexual a otros). Los ejes mencionados son importantes en cómo los entrevistados perciben, viven y aceptan (o no) su orientación sexual. Igualmente, un hallazgo importante es la significación otorgada por los jóvenes entrevistados a la homofobia internalizada, proceso que se sustenta en la construcción e internalización de rígidos roles de género, siendo este tipo de homofobia una de las causas de la discriminación y auto-discriminación que existe entre homosexuales.

Abstract This study discusses how sexual identity is constructed among young gay men of 18-29 years-old from Antofagasta in northern Chile. The study uses a qualitative approach and the selection of participants was intentional. Data was collected via semi-structured interviews. Three categories influencing youth's sexual identity were identified: a) gender socialization, b) discrimination; and c) "coming out of the closet" (revealing sexual orientation to others). Those indicators are important in relation to how interviewees perceive, experience, and accept or not their sexual orientation. In addition, an important finding is the significance given by participants to internalized homophobia. This process is based on the construction and internalization of rigid gender roles. This type of homophobia is one of the causes of discrimination and self-discrimination among homosexuals.

Resumo A investigação em que se baseia este artigo teve como objetivo compreender como se constrói a identidade sexual em homens gay jovens, entre 18 e 29 anos de idade, da cidade da Antofagasta, no norte do Chile. O enfoque da investigação foi qualitativo e a seleção dos participantes foi de caráter intencional. A técnica de produção de informação foi a entrevista semiestruturada. Identificaram-se três categorias que incidem na construção da identidade sexual dos jovens entrevistados: a) a socialização de gênero; b) a discriminação; c) a "saída do armário" (revelação da orientação sexual a outros). Os eixos acima mencionados são importantes em relação a como os entrevistados percebem, vivem e aceitam (ou não) sua orientação sexual. Igualmente, um achado importante é a significação outorgada pelos jovens entrevistados à homofobia internalizada, processo que se sustenta na construção e na internalização de rígidos papéis de gênero, sendo este tipo de homofobia uma das causas da discriminação e da autodiscriminação que existem entre homossexuais.

Esporotricosisliinfaggitica / Lymphangitic Sporotrichosis

La esporotricosis es una infección micótica de evolución subaguda o crónica que puede afectar a humanos y animales, la cual está caracterizada por presentar lesiones nodulares cutáneas y subcutáneas, su incidencia varia en las distintas regiones de sudamerica. Se presenta el caso de un paciente varón de 28 años de edad con el diagnóstico de esporotricosis linfangítica, que tardó alrededor de tres meses en ser diagnosticado; se realiza un análisis y seguimiento de la evolución haciendo especial mención en los aspectos clínicos, diagnósticos y terapéuticos de esta enfermedad con la finalidad de alertar un diagnóstico precoz y tratamiento oportuno.

The esporotricosis is a mycotic infection of subacute or chronic evolution that can concern human beings and animáis, which is characterized for presenting nodular cutaneous and subcutaneous injuries, its incidente is different regions of sudamerica. There appears the case of a 28-year-old patient male of age with the diagnosis of esporotricosis linfangítica, that was late about three month in being diagnosed; there is realized an analysis and follow-up of the evolution doing special mention on the clinical, diagnostic and therapeutic aspects of this disease with the purpose of real a precocious diagnosis and opportune treatment.

Cardiotocografí en el diagnóstico de distocia unicular: hospital materno infaantil "germán urquidi"

Se realiza un estudio prospectivo, longitudinal, en el Hospital Materno Infantil "Germán Urquidi", en el período comprendido entre el 1 de enero al 31 de diciembre de 2007, para determinar la utilidad de la cardiotocografía en el diagnóstico de distocia funicular, realizándose 178 estudios cardiotocográficos en gestantes que cumplían los criterios de inclusión del presente trabajo, con el fin de identificar la existencia de signos cardiotocográficos sugestivos de compresión funicular y luego del parto comprobar su existencia. Evidenciando que el estudio cardiotocográfico tiene un valor predictivo negativo y la sensibilidad de 95, 74 y 91,3% respectivamente, demostrando con el estudio que la cardiotocografía intraparto posee una mayor capacidad de identificar fetos comprometidos y en menor proporción a los sanos; así mismo es confiable para descartar la presencia de distocia funicular en los casos donde no existieron signos sugestivos de compresión funicular en el trazado cardiotocográfico.

A prospective longitudinal study, was done in the Hospital Materno Infantil "German Urquidi", between january 1st and december 31st of 2007, to determine the usefulness of the cardiotocography in the diagnostic of funicular distocia, 178 cardiotocographics studies were done in pregnant women that metthe criteria of inclusion ofthe present work, with the end to identify the existence of cardiotocographics signs suggesting the funicular compression and after the birth prove its existence. Confirming that the cardiotocography study has a negative predictive value and a sensibility of 95, 74 and 91,3 % respectively.The study further proves that the intra parto cardiotocography has a major capacity of correctly identifying foetuses compromised and in minor proportion to the healthy ones; this way is trustable to distinguish the presence of funicular disctocia in the cases where no signs existed suggesting the funicular compression in the cardiotocography trace.