RESUMEN
Iodine is essential for normal thyroid function, supporting healthy fetal and child development. Iodine requirements increase in pregnancy, but many women in regions without salt iodization have insufficient intakes. We explored associations between iodide intake and urinary iodine concentration (UIC), urinary iodine/creatinine ratio (I/Cr), thyroid stimulating hormone, thyroglobulin, free triiodothyronine, free thyroxine and palpable goiter in a region of mild-to-moderate iodine insufficiency. A total of 246 pregnant women aged 18-40 in Bradford, UK, joined the Health and Iodine in Babies (Hiba) study. They provided detailed information on diet and supplement use, urine and serum samples and were assessed for goiter at around 12, 26 and 36 weeks' gestation, and 6, 18 and 30 weeks postpartum. Dietary iodide intake from food and drink was estimated using six 24 h recalls. During pregnancy, median (IQR) dietary iodide intake was 101 µg/day (54, 142), with 42% from dairy and 9% from white fish. Including supplements, intake was 143 µg/day (94, 196), with 49% < UK reference nutrient intake (140 µg/day). Women with Pakistani heritage had 129 µg/day (87, 190) median total intake. Total intake during pregnancy was associated with 4% (95% CI: 1%, 7%) higher UIC, 5% (3%, 7%) higher I/Cr, 4% (2%, 6%) lower thyroglobulin and 21% (9%, 32%) lower odds of palpable goiter per 50 µg/day. This cohort consumed less iodide in pregnancy than UK and World Health Organization dietary recommendations. UIC, I/Cr and thyroglobulin were associated with intake. Higher intake was associated with fewer goiters. Because dairy was the dominant source of iodide, women following plant-based or low-dairy diets may be at particular risk of iodine insufficiency.
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Enfermedades Carenciales , Yoduros/análisis , Yodo , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Hormonas Tiroideas/sangre , Adolescente , Adulto , Enfermedades Carenciales/sangre , Enfermedades Carenciales/epidemiología , Enfermedades Carenciales/orina , Dieta/estadística & datos numéricos , Suplementos Dietéticos/estadística & datos numéricos , Femenino , Humanos , Yodo/deficiencia , Yodo/orina , Periodo Posparto/fisiología , Embarazo/estadística & datos numéricos , Reino Unido , Adulto JovenRESUMEN
BACKGROUND: Maternal iodine requirements increase during pregnancy to supply thyroid hormones critical for fetal neurodevelopment. Iodine insufficiency may result in poorer cognitive or child educational outcomes but current evidence is sparse and inconsistent. OBJECTIVES: To quantify the association between maternal iodine status and child educational outcomes. METHODS: Urinary iodine concentrations (UIC) and iodine/creatinine ratios (I:Cr) were measured in 6971 mothers at 26-28 weeks' gestation participating in the Born in Bradford cohort. Maternal iodine status was examined in relation to child school achievement (early years foundation stage (EYFS), phonics, and Key Stage 1 (KS1)), other learning outcomes, social and behavioural difficulties, and sensorimotor control in 5745 children aged 4-7 years. RESULTS: Median (interquartile range) UIC was 76 µg/L (46, 120), and I:Cr was 83 µg/g (59, 121). Overall, there was no strong or consistent evidence to support associations between UIC or I:Cr and neurodevelopmental outcomes. For instance, predicted EYFS and phonics scores (primary outcomes) at the 25th vs 75th I:Cr percentiles (99% confidence intervals) were similar, with no evidence of associations: EYFS scores were 32 (99% CI 31, 33) and 33 (99% CI 32, 34), and phonics scores were 34 (99% CI 33, 35) and 35 (99% CI 34, 36), respectively. CONCLUSIONS: In the largest single study of its kind, there was little evidence of detrimental neurodevelopmental outcomes in children born to pregnant women with iodine insufficiency as defined by World Health Organization-outlined thresholds. Alternative functional biomarkers for iodine status in pregnancy and focused assessment of other health outcomes may provide additional insight.
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Yodo , Niño , Cognición , Femenino , Edad Gestacional , Humanos , Estado Nutricional , Embarazo , Embarazo Múltiple , Reino Unido/epidemiologíaRESUMEN
Severe iodine deficiency in mothers is known to impair foetal development. Pregnant women in the UK may be iodine insufficient, but recent assessments of iodine status are limited. This study assessed maternal urinary iodine concentrations (UIC) and birth outcomes in three UK cities. Spot urines were collected from 541 women in London, Manchester and Leeds from 2004â»2008 as part of the Screening for Pregnancy End points (SCOPE) study. UIC at 15 and 20 weeks' gestation was estimated using inductively coupled plasma-mass spectrometry (ICP-MS). Associations were estimated between iodine status (UIC and iodine-to-creatinine ratio) and birth weight, birth weight centile (primary outcome), small for gestational age (SGA) and spontaneous preterm birth. Median UIC was highest in Manchester (139 µg/L, 95% confidence intervals (CI): 126, 158) and London (130 µg/L, 95% CI: 114, 177) and lowest in Leeds (116 µg/L, 95% CI: 99, 135), but the proportion with UIC <50 µg/L was <20% in all three cities. No evidence of an association was observed between UIC and birth weight centile (-0.2% per 50 µg/L increase in UIC, 95% CI: -1.3, 0.8), nor with odds of spontaneous preterm birth (odds ratio = 1.00, 95% CI: 0.84, 1.20). Given the finding of iodine concentrations being insufficient according to World Health Organization (WHO) guidelines amongst pregnant women across all three cities, further studies may be needed to explore implications for maternal thyroid function and longer-term child health outcomes.
Asunto(s)
Yodo/deficiencia , Estado Nutricional , Complicaciones del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Fenómenos Fisiologicos de la Nutrición Prenatal , Adulto , Peso al Nacer , Ciudades , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Yodo/orina , Evaluación Nutricional , Embarazo , Complicaciones del Embarazo/etiología , Complicaciones del Embarazo/orina , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Diagnóstico Prenatal/métodos , Reino Unido/epidemiologíaRESUMEN
Metabolomics studies of low-biomass organisms, such as small insects, have previously relied on the pooling of biological samples to overcome detection limits, particularly using NMR. We show that the differentiation of metabolite profiles of individual 1 mg parasitoid wasps of different ages is possible when using a modified sample preparation and a combination of untargeted NMR and LC-MS based metabolomics. Changes were observed between newly emerged and older wasps in glycerolipids, amino acids and circulatory sugars. This advance in chemical profiling has important implications for the study of the behaviour and ecology of parasitoids and many other species of small organisms because predictions and observations are typically made at the level of the individual. Thus, the metabolomic state of low-biomass individuals can now be related to their behaviour and ecological performance. We discuss specifically the utility of age-related metabolomic profiling but our new approach can be applied to a wide range of biological research.
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Envejecimiento/fisiología , Metabolómica/métodos , Avispas/metabolismo , Animales , Cromatografía Liquida , Femenino , Metabolismo de los Lípidos , Espectroscopía de Resonancia Magnética , Mariposas Nocturnas/parasitología , Espectrometría de Masa por Ionización de Electrospray , Avispas/química , Avispas/fisiologíaRESUMEN
Many animals avoid attack from predators through toxicity or the emission of repellent chemicals. Defensive mimicry has evolved in many species to deceive shared predators, for instance through colouration and other morphological adaptations, but mimicry hardly ever seems to involve multi-trait similarities. Here we report on a wingless parasitoid wasp that exhibits a full spectrum of traits mimicing ants and affording protection against ground-dwelling predators (wolf spiders). In body size, morphology and movement Gelis agilis (Ichneumonidae) is highly similar to the black garden ant (Lasius niger) that shares the same habitat. When threatened, G. agilis also emits a volatile chemical that is similar to an ant-produced chemical that repels spiders. In bioassays with L. niger, G. agilis, G. areator, Cotesia glomerata and Drosophila melanogaster, ants and G. agilis were virtually immune to spider attack, in contrast the other species were not. Volatile characterisation with gas chromatography-mass spectrometry identified G. agilis emissions as 6-methyl-5-hepten-2-one, a known insect defence semiochemical that acts as an alarm pheromone in ants. We argue that multi-trait mimicry, as observed in G. agilis, might be much more common among animals than currently realized.
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Hormigas/parasitología , Conducta Predatoria/fisiología , Avispas/fisiología , Animales , Hormigas/fisiología , Tamaño Corporal , Drosophila melanogaster/fisiología , Ecosistema , Cromatografía de Gases y Espectrometría de Masas , Cetonas/análisis , Arañas/fisiología , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/metabolismo , Avispas/químicaRESUMEN
Metabolomic analyses can reveal associations between an organism's metabolome and further aspects of its phenotypic state, an attractive prospect for many life-sciences researchers. The metabolomic approach has been employed in some, but not many, insect study systems, starting in 1990 with the evaluation of the metabolic effects of parasitism on moth larvae. Metabolomics has now been applied to a variety of aspects of insect biology, including behaviour, infection, temperature stress responses, CO 2 sedation, and bacteria-insect symbiosis. From a technical and reporting standpoint, these studies have adopted a range of approaches utilising established experimental methodologies. Here, we review current literature and evaluate the metabolomic approaches typically utilised by entomologists. We suggest that improvements can be made in several areas, including sampling procedures, the reduction in sampling and equipment variation, the use of sample extracts, statistical analyses, confirmation, and metabolite identification. Overall, it is clear that metabolomics can identify correlations between phenotypic states and underlying cellular metabolism that previous, more targeted, approaches are incapable of measuring. The unique combination of untargeted global analyses with high-resolution quantitative analyses results in a tool with great potential for future entomological investigations.
RESUMEN
The exoskeleton of insects (cuticle) is an assembly of chitin and cuticle proteins. Its physical properties are determined largely by the proteins it contains, and vary widely with developmental stages and body regions. The genes encoding cuticle proteins are therefore good models to study the molecular mechanisms of signalling by ecdysteroids and juvenile hormones, which regulate molting and metamorphosis in insects. This review summarizes the studies of hormonal regulation of insect cuticle protein genes, and the recent progress in the analysis of the regulatory sequences and transcription factors important for their expression.
Asunto(s)
Ecdisteroides/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos/metabolismo , Insectos/metabolismo , Animales , Proteínas de Insectos/genética , Insectos/genética , Factores de Transcripción/metabolismoRESUMEN
Post-embryonic development in insects requires successive molts. Molts are triggered by ecdysteroids, and the nature of the molt (larval, pupal or adult) is determined by juvenile hormones. The genes encoding cuticle proteins are targets of both classes of hormones, and therefore are interesting models to study hormone action at the molecular level. The Drosophila ACP65A cuticle gene is expressed exclusively during the synthesis of the adult exoskeleton, in epidermal domains synthesising flexible cuticle. We have examined the cis-regulatory sequences of ACP65A using phylogenetic comparisons and functional analysis, and find that only about 180 bp are essential, including an 81 bp intron. The restriction of ACP65A expression appears to depend on a strong repression mechanism.
Asunto(s)
Drosophila melanogaster/fisiología , Regulación de la Expresión Génica/fisiología , Proteínas de Insectos/metabolismo , Animales , Secuencia de Bases , Proteínas de Insectos/genética , Datos de Secuencia Molecular , Filogenia , Elementos Reguladores de la Transcripción , Secuencias Reguladoras de Ácidos NucleicosRESUMEN
Broad (BR), an ecdysone-inducible transcription factor, is a major determinant of the pupal stage. The misexpression of BR-Z1 isoform (BR-Z1) during adult development of Drosophila melanogaster prevents the expression of the adult cuticle protein 65A gene (Acp65A). We found that the proximal 237 bp of the 5' flanking region of Acp65A were sufficient to mediate this suppression. A targeted point mutation of a putative BR-Z1 response element (BRE) within this region showed that it was not involved. Drosophila hormone receptor-like 38 (DHR38) is required for Acp65A expression. We found that BR-Z1 repressed DHR38 expression and that BR's inhibition of Acp65A expression was rescued by exogenous expression of DHR38. Thus, BR-Z1 suppresses Acp65A expression by preventing the normal up-regulation of DHR38 at the time of adult cuticle formation.
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Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas de Insectos/metabolismo , Factores de Transcripción/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Proteínas de Drosophila/genética , Calor , Proteínas de Insectos/genética , Integumento Común/crecimiento & desarrollo , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Unión Proteica , Pupa , Factores de Transcripción/genéticaRESUMEN
OBJECTIVE: To evaluate the protection and acceptability of Urgotul wound dressing in the local management of acute or chronic wounds receiving topical negative pressure (TNP) therapy. METHOD: This was a prospective multicentre non-comparative open-label trial. At each dressing change the investigating physician clinically evaluated and photographed the wound. Planimetric measurement was undertaken and wound depth was assessed at the start and end of the treatment. Follow-up was undertaken until deemed clinically unnecessary by the investigator. RESULTS: Sixty-six patients were included (42 acute wounds and 24 chronic wounds) and followed up for an average of 17 days. Dressing changes were deemed entirely painless in 52% of cases (compared with 18% at baseline) and pain between two consecutive dressing changes was absent in 66% of cases (34% at baseline). Removal of the TNP-interface dressing combination was considered'very easy' or 'easy' in 94% of cases and adherence to the wound was recorded as 'absent' in 88%. On average, the dressings were changed every 3.8 +/- 1.1 days (all wounds were considered), and wound area and depth were reduced by 19% and 54% respectively by the end of the follow-up period. CONCLUSION: Use of the interface dressing in combination with TNP substantially reduced the pain caused by dressing changes. It therefore makes more acceptable the use of this technique, which aims to optimise the management of wounds that are sometimes considered to be in a therapeutic impasse.
Asunto(s)
Vendas Hidrocoloidales/normas , Succión/métodos , Heridas y Lesiones/terapia , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Vendas Hidrocoloidales/efectos adversos , Enfermedad Crónica , Investigación en Enfermería Clínica , Terapia Combinada , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/etiología , Fotograbar , Estudios Prospectivos , Cuidados de la Piel/efectos adversos , Cuidados de la Piel/métodos , Factores de Tiempo , Cicatrización de Heridas , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/etiologíaRESUMEN
The regulatory sequences of the Drosophila ACP65A cuticle gene were analyzed in vivo in transgenic flies, using both fusion genes constructs and transposase-mediated deletions within a P element containing ACP65A regulatory sequences fused to the lacZ gene (deletion scanning). The sequences located between -594 and +161 are sufficient to confer both temporal and spatial expression specificities, indicating the presence of tissue-specific enhancers and response elements to hormone-induced factors. In addition, timing of expression and tissue-specificity appear to be controlled by distinct cis-regulatory elements, which suggests the existence of independent hormonal and tissue-specific signaling pathways. Gain and loss of function studies also implicate DHR38, the Drosophila homolog of the vertebrate NGFI-B-type nuclear receptors, as an important activator of the ACP65A gene.
Asunto(s)
Proteínas de Unión al ADN/fisiología , Proteínas de Drosophila/genética , Drosophila/genética , Regulación de la Expresión Génica/fisiología , Proteínas de Insectos/genética , Receptores Citoplasmáticos y Nucleares/fisiología , Factores de Transcripción/fisiología , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Cruzamientos Genéticos , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/fisiología , Femenino , Proteínas de Insectos/metabolismo , Masculino , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Pupa/genética , Receptores de Esteroides/fisiología , Eliminación de Secuencia , Transcripción GenéticaRESUMEN
A PCR approach has been used to isolate, from Bombyx mori, a cDNA encoding a novel orphan receptor (GRF) that is most closely related to Bombyx betaFTZ-F1 and to the vertebrate germ cell nuclear factor. The major GRF mRNA is detected in most tissues as an 8-kb transcript whose amount follows the circulating ecdysteroid concentration with a delay. The expression pattern of GRF is similar to that of the Bombyx homologue of the Drosophila early-late gene DHR3, and precedes that of betaFTZ-F1 in all stages and tissues examined. The GRF protein is thus likely to be required in many tissues, but in a temporally restricted manner suggesting that GRF has a well-defined function in the ecdysteroid-induced transcription cascade. The GRF protein binds in vitro to a single oestrogen receptor half-site AGGTCA preceded by a 5'-TCA extension, and is therefore a potential co-regulator of the orphan receptors betaFTZ-F1 and DHR39.
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Bombyx/química , Proteínas de Unión al ADN/aislamiento & purificación , ADN/metabolismo , Genes de Insecto , Proteínas de Insectos/aislamiento & purificación , Factores de Transcripción/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Bombyx/crecimiento & desarrollo , Clonación Molecular , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Ecdisterona/farmacología , Factores de Transcripción Fushi Tarazu , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Proteínas de Homeodominio , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Datos de Secuencia Molecular , Miembro 1 del Grupo A de la Subfamilia 6 de Receptores Nucleares , Estructura Terciaria de Proteína , Receptores Citoplasmáticos y Nucleares/química , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Factor Esteroidogénico 1 , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcripción GenéticaRESUMEN
Proteins of the third instar larval cuticle of Drosophila melanogaster, LCP5-LCP9, were purified and their N-terminal sequences determined. Three of these proteins (LCP5, 6, and 8) were found to be encoded by two multicopy genes previously mapped to the gene cluster at 65A 5-6 on the left arm of the third chromosome. The analysis of the patterns of developmental expression of the 8 distinct genes at this site showed that all but two were expressed during larval life. The patterns fell into three groups: one where expression was all through larval life, one where expression was primarily in the third instar, and one only during the production of the adult cuticle. One duplicated gene was not expressed in the Canton S strain at any time from the embryo to adult ecdysis. These findings indicate that there is not a unique set of cuticle proteins in the third versus the first and second instar larval cuticles and indicates that overlapping gene sets in several different gene clusters encode the proteins of the cuticle of different developmental stages.
Asunto(s)
Drosophila melanogaster/genética , Genes de Insecto , Proteínas de Insectos/genética , Familia de Multigenes , ARN/genética , Secuencia de Aminoácidos , Animales , Mapeo Cromosómico , Drosophila melanogaster/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos/aislamiento & purificación , Larva/genética , Larva/crecimiento & desarrollo , Datos de Secuencia Molecular , Homología de Secuencia de AminoácidoRESUMEN
A 36-kb genomic DNA segment of the Drosophila melanogaster genome containing 12 clustered cuticle genes has been mapped and partially sequenced. The cluster maps at 65A 5-6 on the left arm of the third chromosome, in agreement with the previously determined location of a putative cluster encompassing the genes for the third instar larval cuticle proteins LCP5, LCP6 and LCP8. This cluster is the largest cuticle gene cluster discovered to date and shows a number of surprising features that explain in part the genetic complexity of the LCP5, LCP6 and LCP8 loci. The genes encoding LCP5 and LCP8 are multiple copy genes and the presence of extensive similarity in their coding regions gives the first evidence for gene conversion in cuticle genes. In addition, five genes in the cluster are intronless. Four of these five have arisen by retroposition. The other genes in the cluster have a single intron located at an unusual location for insect cuticle genes.
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Drosophila melanogaster/genética , Proteínas de Insectos/genética , Familia de Multigenes , Animales , Secuencia de Bases , ADN Complementario , Evolución Molecular , Dosificación de Gen , Genoma , Datos de Secuencia Molecular , Homología de Secuencia de Ácido NucleicoRESUMEN
A 29-kDa nuclear juvenile hormone (JH)-binding protein from the epidermis of Manduca sexta larvae was purified by using the photoaffinity analog for JH II ([3H]epoxyhomofarnesyldiazoacetate) and partially sequenced. A 1.1-kb cDNA was isolated by using degenerate oligonucleotide primers for PCR based on these sequences. The cDNA encoded a 262-amino acid protein that showed no similarity with other known proteins, except for short stretches of the interphotoreceptor retinoid-binding protein, rhodopsin, and human nuclear protein p68. Recombinant baculovirus containing this cDNA made a 29-kDa protein that was covalently modified by [3H]epoxyhomofarnesyldiazoacetate and specifically bound the natural enantiomer of JH I (Kd = 10.7 nM). This binding was inhibited by the natural JHs but not by methoprene. Immunocytochemical analysis showed localization of this 29-kDa protein to epidermal nuclei. Both mRNA and protein are present during the intermolt periods; during the larval molt, the mRNA disappears but the protein persists. Later when cells become pupally committed, both the mRNA and protein disappear with a transient reappearance near pupal ecdysis. The properties of this protein are consistent with its being the receptor necessary for the antimetamorphic effects of JH.
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Proteínas Portadoras/metabolismo , Proteínas de Insectos , Metamorfosis Biológica/fisiología , Mariposas Nocturnas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Portadoras/genética , Proteínas Portadoras/aislamiento & purificación , ADN Complementario/aislamiento & purificación , Isomerismo , Hormonas Juveniles/metabolismo , Cinética , Larva , Masculino , Datos de Secuencia Molecular , Peso Molecular , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/fisiología , Oligodesoxirribonucleótidos , Reacción en Cadena de la Polimerasa/métodos , Sesquiterpenos/metabolismo , TritioRESUMEN
The accumulation of transcripts from two adult-specific cuticular genes (ACP-20 and ACP-22) is shown to be modified after addition of exogenous 20-hydroxyecdysone. In the continuous presence of high levels of the hormone, the expression of ACP-20 gene is significantly weaker than that of untreated controls, while ACP-22 expression is 2.5-fold increased. During active synthesis of the ACP messages, a 0.5 microg 20-hydroxyecdysone injection causes a rapid 2-fold increase in ACP-22 mRNA and is not able to repress ACP-20 mRNA accumulation. We conclude that these genes whose transcripts appear in an almost coordinated manner in epidermal cells during the moulting cycle are regulated by ecdysteroids in a different way. In order to undertake a functional dissection of the promoter regions of ACP-22 gene, we have isolated and sequenced a genomic clone. The sequence similarities with other cuticular protein genes are discussed.
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Ecdisterona/farmacología , Genes de Insecto , Proteínas de Insectos/genética , Tenebrio/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Southern Blotting , ADN , Regulación de la Expresión Génica , Genoma , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Tenebrio/metabolismoRESUMEN
In Coleoptera, the elytra (forewings), with a very hard and thick cuticle, protect the membranous and delicate hindwings against mechanical stress. We have isolated and characterized a cDNA encoding a major cuticle protein in Tenebrio molitor, named ACP-20. The deduced amino acid sequence is roughly tripartite, with two terminal glycine-rich domains and a central region showing pronounced similarities with some other hard cuticle proteins. Northern blot and in situ hybridization analyses reveal that ACP-20 gene expression is developmentally regulated since transcript accumulation occurs only in epidermal regions synthesizing hard cuticle and is restricted to the period of preecdysial adult cuticle deposition. Moreover, application of a juvenile hormone analogue prevents the appearance of the transcript, indicating that juvenile hormone, a key molecule involved in the control of insect metamorphosis, negatively regulates the expression of the ACP-20 gene.
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Clonación Molecular , ADN/genética , Regulación de la Expresión Génica , Proteínas de Insectos , Metamorfosis Biológica , Proteínas/genética , Tenebrio/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , ADN/química , Electroforesis en Gel Bidimensional , Glicina/análisis , Metamorfosis Biológica/genética , Metamorfosis Biológica/fisiología , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Proteínas/química , Tenebrio/químicaRESUMEN
Patients with suspected coronary artery disease are sometimes unable to exercise adequately (85% of age calculated maximal heart rate) to validate their ergometric stress test. Some groups suggest performing dipyridamole scintigraphy from the outset but then the information provided by exercise stress testing is lost. The aim of this study was to compare scintigraphies performed after exercise alone and after exercise combined with dipyridamole using a method of quantification. Thirteen patients with ischaemic heart disease without necrosis (coronary lesions greater than 75% luminal narrowing in: 7 right coronary, 10 left anterior descending, 3 left circumflex arteries and 1 left main coronary artery with 50% luminal narrowing) underwent exercise stress testing followed by Thallium imaging. One week later, the same exercise stress test was performed followed by an intravenous injection of dipyridamole and Thallium scintigraphy. The circumference of the radioactivity was traced and the surface of each segment calculated in three different short axis views, subdivided into 4 segments (anterior, lateral, inferior and septal walls). Any segment vascularised by a stenosed coronary artery was considered to be underperfused (105 segments). The ratios of the surfaces of underperfused/normal segments were compared using the two study protocols. Segments of the same wall in the 3 short axis views were grouped in the same myocardial zone. Thirty five myocardial zones were thus obtained: 25 zones were more underperfused after combining exercise and dipyridamole than after simple exercise stress (p = 0.014). The average increase in underperfusion after the combined exercise-dipyridamole was 12.4% compared with 5.5% after exercise alone (p = 0.03). Secondary effects were minimal.(ABSTRACT TRUNCATED AT 250 WORDS)
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Enfermedad Coronaria/diagnóstico por imagen , Dipiridamol/administración & dosificación , Corazón/diagnóstico por imagen , Electrocardiografía , Prueba de Esfuerzo , Humanos , Cómputos Matemáticos , Cintigrafía , Radioisótopos de TalioRESUMEN
Changes in translatable mRNAs from the wing epidermis of the Coleoptera Tenebrio molitor have been investigated during metamorphosis by analysis of in vitro translated products. Striking differences between the patterns obtained from mRNAs extracted during pupal and adult cuticle secretion indicated that a drastic change in gene expression occurs during the pupal-adult transition. In addition to these stage-specific modifications, the mRNA patterns changed within each cuticular synthesis program (pupal or adult), especially at ecdysis. After tritiated leucine incorporation, some of the major radiolabeled cuticular proteins showed similar changes suggesting that the sequential appearance of mRNAs corresponds to sequential deposition of cuticular proteins. In supernumerary pupae obtained after juvenile hormone analogue (JHA) application on newly ecdysed pupae, translatable mRNA were very similar to those of pharate pupae. The JHA seemed, therefore, to prevent the expression of the adult program. By immunoblotting in vitro translated products with a monoclonal antibody recognizing an adult-specific cuticular protein, the developmental profile of the corresponding mRNA was studied. This mRNA was detected in anterior wing epidermis during the first 80 hr of the pharate adult stage. Using the same antibody, a cDNA clone was isolated from epidermal mRNA. The hybrid selected mRNA coded for only one protein with an apparent MW of 22 kDa which was, furthermore, recognized by the antibody. The Northern blot analysis performed with the clone confirmed the Western blot analysis of the in vitro translation products. JHA application at the beginning of the pupal-adult reprograming prevented the appearance of this mRNA; however, this transcript was present during the following molting cycle. This reversibility of the JHA action was confirmed by immunogold labeling of the cuticles formed in treated animals.