Better Together: Volatile-Mediated Intraguild Effects on the Preference of Tuta absoluta and Trialeurodes vaporariorum for Tomato Plants.

Plant-herbivore interactions have been extensively studied in tomato plants and their most common pests. Tomato plant chemical defenses, both constitutive and inducible, play a role in mediating these interactions. Damaged tomato plants alter their volatile profiles, affecting herbivore preferences between undamaged and damaged plants. However, previous studies on tomato volatiles and herbivore preferences have yielded conflicting results, both in the volatile chemistry itself as well as in the attraction/repellent herbivore response. This study revisits the volatile-mediated interactions between tomato plants and two of their main herbivores: the leafminer Tuta absoluta and the whitefly Trialeurodes vaporariorum. Tomato plant volatiles were analyzed before and after damage by each of these herbivores, and the preference for oviposition (T. absoluta) and settling (T. vaporariorum) on undamaged and damaged plants was assessed both after conspecific and heterospecific damage. We found that both insects consistently preferred damaged plants over undamaged plants. The emission of herbivore-induced plant volatiles (HIPVs) increased after T. absoluta damage but decreased after T. vaporariorum damage. While some of our findings are in line with previous reports, T. absoluta preferred to oviposit on plants damaged by conspecifics, which differs from earlier studies. A comparison of HIPVs emitted after damage by T. absoluta and T. vaporariorum revealed differences in up- or down-regulation, as well as significant variations in specific compounds (12 for T. absoluta and 26 for T. vaporariorum damaged-plants). Only two compounds, ß-caryophyllene and tetradecane, significantly varied because of damage by either herbivore, in line with the overall variation of the HIPV blend. Differences in HIPVs and herbivore preferences may be attributed to the distinct feeding habits of both herbivores, which activate different defensive pathways in plants. The plant's challenge in simultaneously activating both defensive pathways may explain the preference for heterospecific damaged plants found in this study, which are also in line with our own observations in greenhouses.

Correlating Eucalyptus leaf metabolomics with preference of the bronze bug, Thaumastocoris peregrinus.

Eucalyptus species are among the most planted trees in forestry production, an ever-increasing commercial activity worldwide. Forestry expansion demands a continuous search for preventive and sanitary measures against pests and diseases. Massive application of phytosanitary products is incompatible with the forestry sector, so forest health management must be based on other principles. In this context, studies on insect plant relationships mediated by plant metabolites may contribute information relevant to plant resistance and genotype selection. In this study, we analyzed the leaf metabolome of four Eucalyptus species commonly planted in southern South America, to correlate this chemical information with feeding preference of Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae), an important pest of eucalypt plantations. Gas chromatography mass spectrometry analyses were performed on polar and non-polar leaf extracts from Eucalyptus globulus, Eucalyptus grandis, Eucalyptus robusta, and Eucalyptus tereticornis (Myrtaceae). Feeding preferences were assessed in two-choice laboratory bioassays resulting in a preference gradient of the four plant species. Moreover, a performance bioassay where we contrasted survival and development time between the most and least preferred plants, showed a clear correlation with preference both in survival and developmental time of the most susceptible nymph instar. We found that species with high or low feeding preferences differ significantly in several foliar metabolites, which may be acting as feeding stimulants or deterrents for T. peregrinus. These findings may provide useful criteria for choosing Eucalyptus genotypes when planting in bronze bug infested areas.

Diel Periodicity of 3-Methyl-2-Butenyl Butyrate Emissions by Bronze Bug Males Is Suppressed in the Presence of Females.

The bronze bug, Thaumastocoris peregrinus Carpintero & Dellapé (Heteroptera: Thaumastocoridae), is an exotic emerging pest in Eucalyptus commercial forests in South America, Africa, and southern Europe. Information on the chemical communication system and reproductive ecology of this insect is scant, and it may be relevant for designing management strategies for eucalypt plantations. Males emit large amounts of 3-methyl-2-butenyl butyrate, which attracts conspecific adult males but not females. To learn more about the biological function of this putative male-produced pheromone, we quantified this compound in volatile emissions collected from males, females, and couples, in three 4-h collecting periods during the morning, afternoon, and night of a single 24-h cycle. Our results showed that virgin males emit 3-methyl-2-butenyl butyrate in a diel time pattern, with an almost sevenfold difference between the afternoon emission peak compared to morning or night hours. In addition, we show that in the presence of females, males emit the compound in the same amounts throughout the photocycle. While a definite function cannot yet be attributed to the emission of 3-methyl-2-butenyl butyrate by T. peregrinus males, our findings point to an intraspecific function, possibly one related to male-male competition.

Attraction of Male Nymphs to Adult Male Volatiles in the Bronze Bug Thaumastocoris peregrinus Carpintero & Dellape (Heteroptera: Thaumastocoridae).

The bronze bug, Thaumastocoris peregrinus Carpintero & Dellape (Heteroptera: Thaumastocoridae), is an exotic emerging pest in Eucalyptus commercial forests in South America, Africa and southern Europe. Information on the chemical communication system and reproductive ecology of this insect is scant, and it may be relevant for designing management strategies for eucalypt plantations. Adults and nymphs usually aggregate in the field, possibly by means of chemical signals. Males emit large amounts of 3-methyl-2-butenyl butyrate, which attracts conspecific adult males but not females. The ecological role of this putative male aggregation pheromone remains unknown. Here, we report olfactometer bioassays showing that late-instar male nymphs are also attracted to synthetic 3-methyl-2-butenyl butyrate and to adult male volatile extracts, which contain this compound as the major component. As previously shown for adult females, nymphs that moulted into females were not attracted to either volatile stimulus. The intra-gender attraction of nymphs and adults may be related to the exploitation of food resources, or as a reproductive strategy for newly emerged males. Further studies on the reproductive behaviour and mating system of T. peregrinus will contribute to understanding the ecological significance of male-male, adult-nymph attraction, as well as the practical applications that may result from these findings.

Somatosensory Evoked Potentials of Inferior Alveolar Nerve: confirmation of a possible non-invasive neurophysiological approach.

INTRODUCTION: The use of inferior alveolar nerve (IAN) somatosensory evoked potentials (SEPs) may represent a non-invasive method to evaluate the sensory nerve function in the maxillofacial region. The aim of this work is to confirm the feasibility of a technique, previously reported in the literature, and the data previously obtained. MATERIALS AND METHODS: SEPs were obtained following electrical stimulation (square wave pulses 0.2 millisecond [ms] in duration, 4 to 6.5 mA, 0.7/second repetition rate, 200 averages) of the gum at the mental foramen level, in the IAN region, via a new designed type of intraoral surface electrodes and recorded from the contralateral central scalp sites. RESULTS: We recognized waveforms of sufficient quality and consistently recorded a "W"-shaped response. Peak latencies of waves were at 14, 20, 27, 34 and 43 ms respectively. One side of the lower lip can be compared with the contralateral side. CONCLUSIONS: IAN SEPs, obtained with the present technique, may represent an objective, non-invasive, and reliable way of testing sensory nerve function in the maxillofacial region.

Hyperplastic polyposis: a case report / Polipose hiperplásica: relato de caso

OBJECTIVE: The authors present a case report of hyperplastic polyposis syndrome from the Coloproctology Service, Vitória Apart Hospital, Vitória-ES. CASE STUDY: Our case is a 24-year-old man who suffered from fatigue, malaise and microcytic and hypochromic anemia, whose upper digestive endoscopy presented several hyperplastic polyps in the stomach and whose colonoscopy revealed colonic polyposis mainly in the right colon; the histopathology showed tubular adenoma with moderate atypia in the ascending colon. Thus, a videolaparoscopic right colectomy was performed; the analysis of the surgical fragment showed multiple (more than 30) polyps distributed through the cecum and ascending colon. CONCLUSION: The histopathological diagnosis of hyperplastic polyposis is a challenging task. In general, most polyps are hyperplastic, but serrated and classic adenomas also occur. These associated adenomatous injuries can be the cause of malignant transformation. So far, there is no consensus about the appropriate treatment; however, a colectomy procedure may be beneficial in a scenario of a large number of hyperplastic polyps, concurrent serrated adenomas, or multiple high-risk adenomatous lesions. (AU)

A Síndrome Polipose Hiperplásica (HPS), descrita em 1980, é considerada como a presença de pólipos hiperplásicos múltiplos, grandes e/ou proximais e, ocasionalmente, um número menor de adenomas serrados, adenomas clássicos e pólipos mistos. A grande maioria dos pacientes são assintomáticos, sendo o diagnóstico um achado incidental da colonoscopia. No tocante ao prognóstico, a maioria dos autores considera HPS um achado incidental sem potencial de malignização, porém, estudos recentes têm descrito lesões genéticas sincrônicas à HPS e ao câncer colorretal. OBJETIVO: Os autores apresentam um relato de caso de Síndrome Polipose Hiperplásica do serviço de coloproctologia do Vitória Apart Hospital, Vitória-ES. CASO CLÍNICO: Trata-se de um paciente de 24 anos, masculino, que apresentava fadiga, adinamia e anemia microcitica e hipocrômica que apresentou na Endoscopia Digestiva Alta: diversos pólipos hiperplásicos no estômago e na Colonoscopia: polipose colônica principalmente em cólon direito cujo histopatológico demonstrou adenoma tubular com atipia moderada no ascendente. Para tal foi realizado colectomia direita videolaparoscópica em que a análise da peça mostrou múltiplos pólipos hiperplásicos distribuídos pelo ceco e cólon ascendente, superior a 30. CONCLUSÃO: O diagnóstico histopatológico de HPS é desafiador. Em geral, a maioria dos pólipos são hiperplásicos, mas também ocorrem adenomas serrados e adenomas clássicos. Tais lesões adenomatosas associadas podem ser a causa de transformações malignas. Ainda não há consenso do tratamento adequado, porém, a colectomia pode ser benéfica quando há grande número de pólipos hiperplásicos, adenomas serrados concomitantes ou múltiplas lesões adenomatosas de alto risco. (AU)

Prosthetic mesh contamination during NOTES(®) transgastric hernia repair: a randomized controlled trial with swine explants.

PURPOSE: Natural Orifice Translumenal Endoscopic Surgery (NOTES(®)) is a developing field in minimally invasive surgery that has been applied across a wide range of procedures; however, infectious concerns remain. Most of the applications have been for extraction, rather than reconstructive procedures. Prosthetic hernia repair, is a constructive procedure, has the unique challenge of avoiding contamination and infection of a permanent implant. Utilizing a novel device, we hypothesize that we can significantly reduce or eliminate prosthetic contamination during a transgastric approach for delivery of a clinically relevant, permanent, synthetic prosthetic. METHODS: 20 swine explants of stomach with attached esophagus were prepared by placing an ultraviolet (UV) light sensitive gel within the lumen of the stomach. Each stomach then underwent endoscopic gastrotomy utilizing a needle, wire guide, and 18-mm balloon dilator. A 10 × 15 cm polypropylene prosthetic was rolled and tied with a 2-0 silk suture, and delivered with one of two methods. Group A (control) utilized a snare to grasp the prosthetic adjacent to the endoscope, which was used to drag it through the gastrotomy. Group B (device) utilized a modified esophageal stent delivery system to deliver the prosthetic through the gastrotomy. Each prosthetic was then digitally photographed with UV illumination, with the contaminated areas illuminating brightly. Software analysis was performed on the photographs to quantify areas of contamination for each group. Statistical analysis was performed using a two-tailed t test with unequal variance. RESULTS: Group A demonstrated a mean of 57 % of the surface area of the prosthetic contaminated with UV light sensitive gel. Group B (experimental group) showed a mean of 0.01 % of the surface area contaminated (p < 0.0001). 95 % confidence intervals indicated that the unprotected delivery technique exposes approximately 6,000 times more of the surface area to contamination than the delivery device. CONCLUSION: Use of this modified stent delivery system can nearly eliminate prosthetic contamination when placed via a transgastric approach in a swine explants model. Theoretically, the reduced inoculum size would reduce or eliminate clinical infection. Since the inoculum size required for clinical prosthetic infection for intraperitoneal mesh is unknown, further study is warranted to test the ability to eliminate clinical infection related to prosthetic delivery with this technique.

Origin of Epilachnapaenulata defensive alkaloids: incorporation of [1-13C]-sodium acetate and [methyl-2H3]-stearic acid.

Ladybird beetles produce a large number of defensive alkaloids. Previous studies suggest that the structural diversity of these endogenous alkaloids can be traced to a common biosynthetic route based on the condensation of several acetate units. In this study, adults of Epilachna paenulata, a phytophagous neotropical species, were fed on diet enriched with potential precursors (sodium acetate, fatty acids and the amino acids lysine and ornithine) labeled with stable isotopes ((13)C, (2)H and (15)N). Labeled acetate was incorporated into the structurally related homotropane and piperidine alkaloids. The later also showed incorporation of [methyl-(2)H3] stearic acid. Our results hence support a fatty acid pathway for the biosynthesis of E. paenulata alkaloids. To our knowledge, this is the first report on the incorporation of a labeled fatty acid into a defensive piperidine alkaloid in insects.

Fate of an alkaloidal nuptial gift in the moth Utetheisa ornatrix: systemic allocation for defense of self by the receiving female.

In the moth Utetheisa ornatrix defensive pyrrolizidine alkaloids are sequestered by both sexes as larvae from their foodplants. The adult male transmits some of this alkaloid to the female at mating for eventual incorporation into the eggs. We now show by chemical analyses that the female herself is the first beneficiary of the alkaloid she receives from the male. By the end of mating the male's alkaloid is found already to be generally distributed throughout the female's body (including even the wings), while it is still largely absent from the ovaries. This result is in line with our earlier finding that the male's alkaloidal gift can itself suffice to render a female fully protected against spiders from the moment she uncouples from the male.

Chemical defense against predation in an insect egg.

The larva of the green lacewing (Ceraeochrysa cubana) (Neuroptera, Chrysopidae) is a natural predator of eggs of Utetheisa ornatrix (Lepidoptera, Arctiidae), a moth that sequesters pyrrolizidine alkaloids from its larval foodplant (Fabaceae, Crotalaria spp.). Utetheisa eggs are ordinarily endowed with the alkaloid. Alkaloid-free Utetheisa eggs, produced experimentally, are pierced by the larva with its sharp tubular jaws and sucked out. Alkaloid-laden eggs, in contrast, are rejected. When attacking an Utetheisa egg cluster (numbering on average 20 eggs), the larva subjects it to an inspection process. It prods and/or pierces a small number of eggs (on average two to three) and, if these contain alkaloid, it passes "negative judgement" on the remainder of the cluster and turns away. Such generalization on the part of the larva makes sense, because the eggs within clusters differ little in alkaloid content. There is, however, considerable between-cluster variation in egg alkaloid content, so clusters in nature can be expected to range widely in palatability. To check each cluster for acceptability must therefore be adaptive for the larva, just as it must be adaptive for Utetheisa to lay its eggs in large clusters and to apportion alkaloid evenly among eggs of a cluster.

Sexually transmitted chemical defense in a moth (Utetheisa ornatrix).

The arctiid moth Utetheisa ornatrix is protected against predation by pyrrolizidine alkaloids (PA) that it sequesters as a larva from its food plant. Earlier work had shown that males transmit PA to the female with the sperm package and that the female bestows part of this gift on the eggs, protecting these against predation as a result. We now show that the female herself derives protection from the gift. Females deficient in PA are vulnerable to predation from spiders (Lycosa ceratiola and Nephila clavipes). If mated with a PA-laden male, the females become unacceptable as prey. The effect takes hold promptly and endures; females are unacceptable to spiders virtually from the moment they uncouple from the male and remain unacceptable as they age. Chemical data showed that the female allocates the received PA quickly to all body parts. We predict that other instances will be found of female insects being rendered invulnerable by receipt of sexually transmitted chemicals.

Defensive production of formic acid (80%) by a carabid beetle (Galerita lecontei).

The carabid beetle Galerita lecontei has a pair of abdominal defensive glands that secrete a mixture of formic acid, acetic acid, and lipophilic components (long-chain hydrocarbons and esters). Formic acid, at the concentration of 80%, is the principal constituent. The beetle ejects the secretion as a spray, which it aims accurately toward parts of the body subjected to assault. At full capacity, the glands store 4.5 mg of formic acid (3% of body mass), enough for upward of six ejections. The beetle reloads the glands at a rate of 126 microg of formic acid per day. For the approximately 500 secretory cells of the glands, this means an hourly output of 10 ng of formic acid per cell, or about 5% of cell volume. Replenishing empty glands to their full formic acid load takes the beetle an estimated 37 days. Replenishing the 0.7 mg of formic acid expended in a single discharge takes 5.5 days.

Structure, organization and promoter expression of the actin-encoding gene in Trichoderma reesei.

The single gene encoding actin (Act) in the cellulolytic filamentous fungus Trichoderma reesei (Tr) has been isolated and characterized. The gene contains five introns located in identical positions when compared to the putative ancestral actin genes (act) present in Thermomyces lanuginosus and Aspergillus nidulans. The 5' untranslated region (UTR) of the gene contains a TATA-like sequence (TAATA), a C + T-rich region and a potential CCAAT motif. This region was used as a homologous promoter to direct expression of hygromycin-B-resistance-encoding gene as a dominant-selectable Tr marker.

Mitochondrial functions mediate cellulase gene expression in Trichoderma reesei.

We examined the effects of inhibition of mitochondrial functions on the expression of two nuclear genes encoding the extracellular cellobiohydrolase I (cbh1) and endoglucanase I (egl1) of the cellulase system of the filamentous fungus Trichoderma reesei. The cbh1 and egl1 transcripts are repressed at a low oxygen tension, and by glucose at a concentration known to repress mitochondrial respiration. The transcripts are also down-regulated by chemical agents known to dissipate the proton electrochemical gradient of the inner mitochondrial membrane and blocking of the electron-transport chain, such as DNP and KCN, respectively. These results suggest that expression of those transcripts is influenced by the physiological state of the mitochondria. In addition, heterologous gene fusion shows that the sensitivity of the expression of those transcripts to the functional state of the mitochondria is transcriptionally controlled through the 5'-flanking DNA sequence of those genes.

Hormonal regulation of ribosomal RNA synthesis in immature rat uterus

Fraçöes nucleares e nucleolares de útero de ratas jovens injetadas com 17-ß-estadiol näo radioativo foram isoladas e caracterizadas morfológica e bioquimicamente. A análise destas preparaçöes revelou que estas encontravam-se substancialmente puras, com a alfa-amanitina inibindo apenas apenas 20%% da atividade transcricional em nucléolos isolados. O emprego destas fraçöes nos experimentos utilizando a técnica de troca do 3H-estradiol pelo 17-ß-estradiol näo radioativo injetado préviamente nos animais, levou à determinaçäo de curvas de cinética, saturaçäo e de Scatchard para núcleos e nucléolos. Determinou-se alguns parâmetros físico-químicos que definem a ligaçäo do complexo receptor 17-ß-estradiol em núcleos e nucléolos. Os resultados obtidos mostram que tanto núcleos quanto nucléolos apresentam sítios aceptores para o complexo receptor-17-ß-estradiol, sendo esta ligaçäo saturável e específica devido à inibiçäo por um inibidor competitivo,m o diestilstilbestrol, com valores de Kd = 1,06 x 10**-9 M e 20,41 x10**-8 M; Ka = 0,94 x 10**10 M e 20,05 x 10 M; Bo = 0,49 x 10**9 M e 0,35 x 10**-9 M para nucléolos, respectivamente. Em nucléolos a curva de cinética sugere uma acumulaçäo tardia do complexo receptor-hormônio de características diferentes daquelas apresentadas em núcleos, onde existe uma acumulaçäo precoce deste complexo. A partir dos resultados apresentados neste estudo, conclue-se que em útero de ratas jovens pode haver uma açäo direta do hormônio sobre os genes ribossomais. Tal mecanismo caracteriza um sistema de regulaçäo extremamente preciso e complexo, com a presença de sítios aceptores específicos para a açäo do complexo receptor-hormônio sobre o genoma ribossomal. Tendo estabelecido este ponto, estudos adicionais säo necessários para determinar os mecanismos pelos quais os receptores estimulam as velocidades de transcriçäo e suas possíveis implicaçöes no controle gênico

Sindrome de Peutz-Jeghers: apresentaçao de um caso / Peutz-Jeghers syndrome: a case report

Os autores apresentam um caso de Sindrome de Peutz-Jeghers atendido na Clinica de Colo-proctologia do Hospital Geral de Goiania - INAMPS, com quadro de choque hipovolemico devido a enterorragia. Apos tecerem comentarios a respeito das condutas propedeutica e terapeutica adotadas, discutem os principais aspectos clinicos da doença, levando em consideraçao a literatura existente sobre esta patologia.