Effects of some food additives on some biochemical parameters in young male albino rats and the ameliorative role of royal jelly

Background: the use of food additives is one of the most important problems in the human health nutrition field. Food additives are widely used for various purposes; including preservation, coloring, and sweetening, however, the physiological and biochemical changes may be produced

Aim of the work: was to investigate the protective role of royal jelly [RJ] against abnormalities in metabolic biochemical parameters that induced by these food additives in male albino rats

Materials and Methods: thirty young male albino rats with an average body weight 120-140 g were divided into three groups [10/cage]; Group I: served as normal control group, Group II: rats orally administrated with the mixture which consists of sodium nitrite [NaNO2 0.1 mg/kg b.wt./ day], annatto [0.065 mg/kg b.wt./day] and monosodium glutamate [MSG 15 mg/kg b.wt./day] and Group III: rats orally administrated with the previous mixture and then orally administrated with royal jelly [14.28 mg/kg b.wt./day soluble in maize oil]. At the end of the experiment, blood samples were collected for biochemical estimations which including levels of serum glucose, creatinine, urea, testosterone, thyroid hormones [T3 and T4], activities of AST and ALT, total protein [TP], albumin, total cholesterol, triglycerides, high-density lipoprotein [HDL-c] and low-density lipoprotein [LDL-c]

Results: the present study showed marked elevation in levels of fasting blood glucose, activities of AST, ALT, levels of serum urea, creatinine, TC, TG, LDL-c, VLDLand ratios of TC/HDL-c and LDL-c/HDL-c [risk factors] as well as albumin /globulin ratio and serum thyroid hormones [T3andT4] accompanied with significant reduction in the body weight, serum total proteins, albumin, globulin, albumin/creatinine, testosterone and HDL-C concentrations in the group that administrated with the mixture which consists of [NaNO2, MSG and annatto] as compared to control rats. While administration with royal jelly significantly ameliorated the disturbed biochemical parameters and showed significant improvement in most of these parameters

Conclusion: it could be concluded that royal jelly offers a therapeutic advantage that minimizes the metabolic abnormalities and biochemical changes which induced by these food additives

Un primer análisis de la investigación en México sobre los determinantes sociales de la salud: 2005-2012 / A first analysis of research on social determinants of health in Mexico: 2005-2012

Objetivo. Examinar la investigación hecha en México sobre los determinantes sociales de la salud (DSS) durante el periodo 2005-2012 con base en la caracterización del sistema nacional de investigación en salud y la producción científica sobre este tema. Material y métodos. Análisis en dos etapas: revisión documental de fuentes oficiales sobre investigación en salud en México y búsqueda sistemática de literatura sobre DSS. Resultados. Los DSS fueron mencionados en el Programa de Acción Específico de Investigación en Salud 2007-2012, pero no figuran en las estrategias y objetivos; en su lugar, se enfatizan primordialmente aspectos de infraestructura y administrativos. En el periodo se publicaron 145 artículos sobre DSS, cuyas temáticas más abordadas fueron "condiciones de salud", "sistemas de salud" y "nutrición y obesidad". Conclusiones. A pesar de que existe investigación en México sobre DSS, la instrumentación de esos hallazgos en políticas de salud no se ha implementado. El Programa Sectorial de Salud 2013-2018 representa una ventana de oportunidad para posicionar resultados de investigación que promuevan políticas de equidad en salud.

Objective. To examine the research on social determinants of health (SDH) produced in Mexico during the period 2005-2012, based on the characterization of the national health research system and the scientific production on this topic. Materials and methods. Two-stage analyses: Review of Mexican documents and official sources on health research and systematic bibliographic review of the literature on SDH. Results. Although SDH were mentioned in the Specific Action Plan for Health Research 2007-2012, they are not implemented in strategies and goals, as the emphasis is put mostly in infrastructure and administrative aspects of research. In the period studied, 145 articles were published on SDH topics such as health conditions, health systems and nutrition and obesity. Conclusions. In spite of the availability of research on SDH in Mexico, the operationalization of such findings into health policies has not been possible. The current Sectorial Program on Health 2013-2018 represents a window of opportunity to position research findings that promote health equity policies.

Egg-laying rhythm in Drosophila melanogaster.

Extensive research has been carried out to understand how circadian clocks regulate various physiological processes in organisms. The discovery of clock genes and the molecular clockwork has helped researchers to understand the possible role of these genes in regulating various metabolic processes. In Drosophila melanogaster, many studies have shown that the basic architecture of circadian clocks is multi-oscillatory. In nature, different neuronal subgroups in the brain of D. melanogaster have been demonstrated to control different circadian behavioural rhythms or different aspects of the same circadian rhythm. Among the circadian phenomena that have been studied so far in Drosophila, the egg-laying rhythm is unique, and relatively less explored. Unlike most other circadian rhythms, the egg-laying rhythm is rhythmic under constant light conditions, and the endogenous or free-running period of the rhythm is greater than those of most other rhythms. Although the clock genes and neurons required for the persistence of adult emergence and activity/rest rhythms have been studied extensively, those underlying the circadian egg-laying rhythm still remain largely unknown. In this review, we discuss our current understanding of the circadian egg-laying rhythm in D. melanogaster, and the possible molecular and physiological mechanisms that control the rhythmic output of the egg-laying process.

Rhodnius prolixus Malpighian tubules and control of diuresis by neurohormones

Rhodnius prolixus Malpighian tubules (MTs) are a good model for fluid and ion secretion studies in view of the dramatic postprandial diuresis, which follows its massive blood meals. Ingestion of a blood meal equals to 10-12 times their initial body mass, leads to rapid activation of high output by excretory system, which eliminates 40-50 percent of the fluid mass. Secretion of ions and water is stimulated 1000-fold by serotonin and diuretic hormone. These hormones cooperate synergistically to activate adenylate cyclase activity from MTs cells, which increase the level of intracellular cAMP. The anti-diuretic hormones have also an important role in the fluid maintenance of Rhodnius prolixus. Several hours after insect feeding occurs a reduction in urine flow, that has been thought to result from a decreased diuretic hormone release or from a novel mechanism of anti-diuresis involving insect cardioacceleratory peptide 2b (CAP2b) and cyclic GMP. In this article it is discussed how the hormone regulation of fluid transport is done in Rhodnius prolixus MTs.

Os túbulos de Malpighi (TMs) de Rhodnius prolixus são reconhecidos por serem excelentes modelos para o estudo da secreção de fluidos e íons devido a grande diurese que ocorre quando esses animais se alimentam de sangue. O inseto, após alimentação, pode aumentar seu peso corporal inicial em até 10-12 vezes, o que leva a rápida ativação do sistema excretor, que elimina 40-50 por cento do fluido corporal. A secreção de íons e água é estimulada 1000 vezes pela serotonina e pelos hormônios diuréticos. Esses hormônios agem sinergicamente ativando a adenil ciclase das células dos TMs, aumentando os níveis intracelulares de AMPc. Os hormônios anti-diuréticos também têm um importante papel na manutenção dos fluídos corporais do Rhodnius prolixus. Várias horas após a alimentação do inseto ocorre uma redução do fluxo urinário, o que foi sugerido ser decorrente da diminuição da liberação dos hormônios diuréticos ou da anti-diurese envolvendo o peptídeo cardioaceleratório 2b (CAP2b) e o GMPc. Neste artigo é discutida a regulação hormonal do transporte de fluido nos MTs de Rhodnius prolixus.

Effect of juvenile hormone III on the ultrastructure of the corpora allata in Melipona quadrifasciata (Hymenoptera,. Apidae, Meliponýný)

Changes in hormonal levels can produce alternative phenotypes. Juvenile hormone III plays an importantrole in the regulation of metamorphosis, caste determination and age in bees. In this work, we examined theultrastructure of corpora allata cells from stingless bees (Melipona quadrifasciata) treated with juvenilehormone during development. The corpora allata cells of M. quadrifasciata queens showed greater activitythan those of workers. The topical application of juvenile hormone III altered the cellular ultrastructureand either delayed development (as shown by fewer mitochondria and greater chromatin condensation) orenhanced development (looser chromatin and numerous mitochondria) when compared to untreated (control)bees. Our results show that corpora allata cells differ in their ultrastructural characteristics and that thecessation of juvenile hormone production by these cells in M. quadrifasciata is not synchronous.

Cell death in the Germline: mechanisms and consequences for reproductive plasticity in social bees

Its serial architecture makes the insect ovary an interesting playground to study the regulation of cell death and identify critical check points along the apical-basal axis of the ovarioles. In Drosophila melanogaster, cell death is observed at two points: (1) in the germarium, where entire germ cell clusters may die in response to environmental conditions, and (2) as an obligatory event at the end of oogenesis, when nurse cells dump their cytoplasm into the oocyte and, subsequently, when the follicle epithelial cells form a chorion. The social organization of bees, wasps and ants depends on the monopolization of reproduction by a queen. This has marked consequences on the ovary phenotype of queens and workers. The role of programmed cell death in larval ovary development and in adult ovary function is best studied in honey bees. During larval development, workers loose over 90% of the ovariole primordia. This cell death is induced by a low juvenile hormone titer causing breakdown of the actin cytoskeleton in germ cell clusters. The actin cytoskeleton also plays a major role in the control of cell death in the ovary of adult bees, where many TUNEL-labeled and pycnotic nuclei are detected in a germarial region rich in actin agglomerates. This suggests that common mechanisms may regulate cell death in the ovaries of bees, both during the shaping of the caste-specific ovary phenotypes during larval development, and during the tuning of reproductive activity in adult bees.

Desenvolvimento de um modelo para previsão de ocorrência do bicho-furão-dos-citros, Ecdytolopha aurantiana (Lima) (Lepidoptera: Tortricidae / Development of a model to predict the occurrence of citrus fruit borer, Ecdytolopha aurantiana (Lima) (Lepidoptera: Tortricidae)

O presente trabalho teve como objetivo desenvolver um modelo para previsão de ocorrência do bicho-furão-dos-citros, Ecdytolopha aurantiana (Lima). Para tanto, 553 áreas localizadas em 17 fazendas do estado de São Paulo foram monitoradas por meio de armadilhas com feromônio sexual de E. aurantiana durante um ano. O tipo de solo, temperatura mensal média do local, variedade de citros, idade das plantas e uso de agroquímicos para o controle de E. aurantiana, foram utilizados como variáveis para cada área mencionada. A maior influência sobre a flutuação populacional do bicho-furão-dos-citros foi exercida pelo tipo de solo, seguido pela temperatura mensal média do local, variedade de citros, idade das plantas e uso de agroquímicos. A ocorrência de E. aurantiana em função da temperatura foi diferente para cada combinação de tipo de solo, variedade de citros, idade das plantas e uso de agroquímicos. O modelo desenvolvido pode prever o potencial de ocorrência de E. aurantiana em função da temperatura ou dos meses do ano, levando-se em consideração o tipo de solo, variedade de citros, idade das plantas e aplicação de agroquímicos. O programa (BF) elaborado na linguagem R conta com equações para simular as diversas situações de ocorrência de E. aurantiana. O modelo de previsão de ocorrência de bicho-furão pode ser aperfeiçoado com a coleta de dados mais regulares e de forma contínua.

The goal of this work was to develop a model to predict the occurrence of Ecdytolopha aurantiana (Lima), based on monitoring data collected through sexual pheromone traps. Soil type, site temperature, citrus variety, age of plants and use of chemicals to control E. aurantiana influenced the population dynamics of the insect. The highest influence was exerted by the soil type, followed by site temperature, citrus variety, age of plants and the use of chemicals for E. aurantiana control. The occurrence of E. aurantiana according to temperature is different for each combination of soil type, citrus variety, age of plants and use of chemicals. The model developed can predict the occurrence potential of E. aurantiana according to temperature or months of the year, taking into account soil type, citrus variety, age of plants and chemicals spraying. The elaborated software (BF), designed in R language, includes equations that simulate the various situations of E. aurantiana occurrence. The predicting model of citrus fruit borer occurrence can be improved with more frequent and continuous data collecting.

PTTH--a potential growth activator in silkworm, Bombyx mori L. for enhancing silk production.

In silkworm, prothoracicotropic hormone (PTTH), directly or indirectly controls silk production and spinning activity along with juvenile hormone (JH). An effort was made to exploit the potential of PTTH by indirectly activating silk gland for increasing silk productivity using short chain synthetic analogues of PTTH. The analogy in action was also established using PTTH extracted from the silkmoth. Different doses of 42 synthetic PTTH analogues, viz., 2.5, 5, 10 and 20ppm and 3.3 mg/ml of PTTH extracted from silkmoth heads were administered orally to V instar silkworm larvae (Race:KAxNB4D2 and PMxNB4D2) at 0-144 hr at an interval of 24 hr. The analysed data showed an improvement of about 14 - 23% in KA x NB4D2 and about 10-14% in PMxNB4D2 in respect of cocoon shell weight on administration of some of the synthetic PTTH analogues. The PTTH extracted from the adult brain also showed similar effect. The structural analogy of synthetic PTTHs (which improved the shell weight) with original PTTH and its probable mode of action in silkworm are discussed.

Construction of a gene enconding the insect bactericidal protein attacin. Studies on its expression in Escherichia coli

Attacin, a bactericidal small protein is produced by the giant silk moth Hyalophora cecropia. This paper deals with our efforts to clone the attacin cDNA in a bacterial vector to express it in Escherichia coli and produce the protein in sufficient amount, for further studies. We chose two inducible expression vector/bacterial cell systems: pPL-lambda/N99cI+ cells which is able to be induced by nalidixic acid, and pET3d/BL21(DE3) cells carrying a T7 RNA polymerase gene which is IPTG-inducible. After cloning in the pPL-lambda system and under no addition of the inducer, isolated transformants carried this plasmid with at least 2 concurrent deletions that drastically affected attacin expression, even though attacin gene seems to be intact as deduced by its PCR amplification. It was concluded that basal attacin expression occurred in this system and bacterial growth was limited. Plasmid deletions may have emerged by selection pressure as a way to avoid bactericidal expression and allow bacteria survival. The second cloning attempt was done in pET3d vector/BL21 cells, that should not express the cloned sequence (they lack T7 RNA polymerase gene). Transformed BL21 cells gave 3 recombinant plasmids, 2 of them presented a C deletion that generated an early stop signal in the attacin coding region. The third clone, pET-ATT18, carrying an intact gene, was transferred to BL21(DE3)-IPTG inducible cells in order to be expressed. Attacin was undetectable in stained gels or by Western blot analysis. However, expression was visualized in grown cells after 30 min of IPTG induction and 5 min of [35S]-methionine labeling, as a 22.5 kDa protein band by using gel electrophoresis and fluorography. This low level of expression drastically affected bacterial growth. Considering that attacin has no lytic activity, these results suggest that this molecule should block bacterial growth directly at the cytoplasm by an unknown mechanism, since no signal peptide coding sequence was incorporated in this gene construction, precluding periplasmic or external destination of this protein

Los insecticidas actuales y las perspectivas de los nuevos para el futuro / Prospective and opportunistic analysis on insecticides for the future

La importancia de los pesticidas sintéticos orgánicos continuará creciendo acompañando al aumento de la población mundial y en tanto la proporción de tierra cultivable se mantenga relativamente constante. Los pesticidas permiten salvar el 10 por ciento de los cultivos pero todavía un 37 por ciento se pierden anualmente debido a la acción de las plagas. Se pueden tomar a los insecticidas como modelo para ilustrar la necesidad y posibilidades futuras de agroquímicos más eficaces y seguros para el hombre y su medio. Los insecticidas más importantes en ventas constituyen el 88 por ciento del total y actúan a nivel de sólo cuatro blancos moleculares (targets) nerviosos: Acetilcolinesterasa (AChE) el 62 por ciento; Canales de Sodio-dependientes de voltaje el 18 por ciento; Canales de Cloruro-dependientes de GABA (ácido gama aminobutírico) el 6 por ciento y Receptor Nicotínico para la acetilcolina el 2 por ciento. La utilidad de los tres "targets" primeros, será gradualmente comprometida debido a problemas de resistencia de insectos, en tanto que el receptor nicotínico para acetilcolina se espera que crezca significativamente. Los compuestos que actúan sobre targets No-Nerviosos se convertirán progresivamente en mucho más importantes. Dentro de éstos se incluyen a los desacoplantes de la fosforilación oxidativa, a los inhibidores de la NADH/Ubiquinona óxido-reductasa y a los inhibidores de la ATP-asa, a los reguladores del crecimiento (juvenoides, ecdisona) y a los pesticidas microbianos que actúan en varios nuevos targets. Con un panorama de 300 insecticidas comerciales disponibles en la actualidad y la prospectiva de introducción de no más de 2 ó 3 nuevos compuestos por año en promedio, sería esencial que se hiciera un uso lo más efectivo posible de los insecticidas corrientes. Los compuestos químicos más nuevos son en general más complejos y más costosos comparados con los anteriores, pero se los usa en general a dosis mucho menores resultando una relación costo/efectividad que resulta favorable a la economía minimizando además el impacto ambiental. Los nuevos compuestos son en general activos en contra de las cepas resistentes, integrales además a los programas de M.I.P. (manejo integrado de plagas) y suelen poseer una mínima toxicidad en los mamíferos

Curso internacional de entrenamiento de post-grado en Bioquínmica y toxicología de insectos / International course of training of post-grade in insect biochemis try and toxicology

Resume los contenidos de un cursos teórico-práctico dictado en la ciudad de Buenos Aires, sobre diversos aspectos de la bioquímica y toxicología de insectos: mecanismos hormonales, hormonas juveniles y ecdisona; metabolismo de lípidos y transporte de ecdisona en el Triatoma infestans; acción de insecticiadas; embriogénesis; biosítesis de componentes cuticulares (quitina) y metabólicos (trehalosa); y, cultivos de tejido de insectos

Mecanismos endocrinos en la regulación del desarrollo de triatominos / Endocrine mechanisms in the regulation of the development of triatominae

Se estudian los mecanismos endocrinos que intervienen en la regulación del desarrollo del Triatoma infestans y otros triatominos, analizándose el rol fisiológico que cumplen las hormonas juveniles (en la diferenciación al estadio adulto, como hormonas gonadotróficas en las hembras; y como estimulantes de la síntesis de feromonas en adultos), su concentración y metabolismo; así como la estructura, biosíntesis, transporte en la hemolinfa, concentración y metabolismo de la ecdisons (ecdisteroide)