Host plant intraspecific variation determines gall traits.

Galls display a multiplicity of traits, including colours, which are driven by pigment accumulation. Their conspicuousness has attracted researchers' attention and several hypotheses have been raised. However, plants themselves vary intra-specifically, including in their pigment concentrations. As galls are a result of host tissue development, colours may be a by-product of the host's own traits, being more conspicuous simply because the sites where galls develop already have the predisposition to accumulate more pigment. Here, we call this the host variation hypothesis. We test this hypothesis using the system of galls induced by Palaeomystella oligophaga on Macairea radula host plant. Using spectrophotometry, we calculated the Anthocyanin Reflectance Index (ARI) of gall projections, which are responsible for their characteristic colours. We tested the influence of occupant identity (galling insect or any natural enemy), gall volume, parenchyma thickness, height from the ground, ARI of leaf, ARI of gall surface and ARI of the respective stem. We corroborated the host variation hypothesis since the anthocyanin content in stems and in galls' projections were positively related. Moreover, anthocyanin in galls' projections was positively related to anthocyanin in the gall surface and negatively related to gall volume and parenchyma thickness. This shows that, besides the host specificities, galls' own traits may also be responsible for pigment accumulation, influencing their colours. In this study, using colour as an example, we show that although galls tend to be considered complex expressions of galling insects' stimuli, their traits may be simply influenced by previous and specific attributes of the host organs.

Gall traits and galling insect survival in a multi-enemy context / Características de las agallas, y supervivencia de insectos que producen agallas, en el contexto de enemigos múltiples

Introduction: The enemy hypothesis postulates that gall traits protect galling insects against natural enemies. Galls show a huge range of sizes, colors and ornaments, which vary even intraspecifically. However, galling insects are targets of various organisms that attack them directly or indirectly. In this context, to consider only one gall trait to investigate gall structure acting against only one guild of enemies can conceal an understanding of the community-level interactions. Objective: Herein, we take these ideas into consideration to investigate the conspicuous galls induced by Palaeomystella oligophaga Becker and Adamski 2008 (Lepidoptera) on Macairea radula (Bonpl.) (Melastomataceae) as a model system. We characterize this system through categorization of the different enemy guilds present in the community. We identified them to the lowest taxonomic level possible and determined the kind of interaction responsible for galling insects' deaths. Considering the enemy hypothesis and the selection of secondary characteristics, we also aimed to determine which of the multiple gall traits influence the survival success of galling insects in a multi-enemy context. Methods: We inspected galls and characterized the enemy guilds affecting the galling insect and the mortality rates produced by each one of them. Next, we tested whether the distinct gall traits measured (parenchyma thickness, color, projections) promote galling insect survival with respect to each enemy. Results: The mortality induced by indirect enemies (organisms that interact with gall tissues and can interact secondarily with galling insect) was 47.3 %, being higher than that caused by parasitoids and predators (31.5 %). Despite the gall's structural complexity, live galling insects showed the smallest occurrence (21.2 %). Parenchyma thickness was negatively related to Calliephialtes parasitoids, Gelechiidae cecidophages and predation signals. Conclusions: We demonstrated that the attacks to gall tissues by the cecidophages represented the highest threat to P. oligophaga survival, being higher than the mortality caused by direct enemies. That is, the gall traits were not as efficient as supposed to protect the galling insect from the attack of natural enemies. Nevertheless, we also demonstrated that parenchyma thickness can be negatively related to some organisms, especially direct enemies. Other traits hypothesized as defensive (e.g. projections, coloration) may simply play no role.

Introducción: La hipótesis del enemigo postula que las características de la agalla protegen al agallero contra los enemigos naturales. Las agallas muestran una gran variedad de tamaños, colores y adornos, que varían incluso de forma intraespecífica. Sin embargo, los agalleros son objetivos de varios organismos que los atacan directa o indirectamente. En este contexto, considerar solo una característica para investigar la estructura de la agalla actúando contra un solo gremio de enemigos puede ocultar una comprensión de las interacciones a nivel comunitario. Objetivos: Para investigar las ideas presentadas usamos las agallas conspicuas inducidas por Palaeomystella oligophaga Becker y Adamski 2008 (Lepidoptera) en Macairea radula (Bonpl.) (Meslastomataceae) como sistema modelo. Describimos este sistema a través de la categorización de los diferentes gremios enemigos presentes en la comunidad. Los identificamos al nivel taxonómico más bajo posible y determinamos el tipo de interacción responsable de la muerte de los agalleros. Teniendo en cuenta la hipótesis del enemigo y la selección de características secundarias, también buscamos determinar cuáles de las múltiples caracteristicas de la agalla influyen en el éxito de supervivencia de los agalleros en un contexto de enemigos múltiples. Métodos: Inspeccionamos las agallas y caracterizamos los gremios enemigos que afectan al agallero y las tasas de mortalidad producidas por cada uno de ellos. Luego, probamos si las distintas caracteristicas de las agallas medidas (grosor del parénquima, color, proyecciones) promueven la supervivencia de los agalleros con respecto a cada enemigo. Resultados: La mortalidad indirecta inducida por los cecidofagos fue del 47.3 %, superior a la causada por los parasitoides y los depredadores (31.5 %). Apesar de la complejidad estructural de la agalla, los agalleros vivos mostraron la menor presencia (21.2 %). El grosor del parénquima se relacionó negativamente con los parasitoides de Calliephialtes, los cecidófagos de Gelechiidae y la depredación. Conclusiones: Demostramos que los ataques a los tejidos biliares por cecidófagos representaron la mayor amenaza para la supervivencia de P. oligophaga. Esto es interesante porque, de acuerdo con la hipótesis del enemigo, la estructura de las agallas debería proporcionar protección para los insectos agalleros en lugar de atraer a los insectos que se alimentan de la agalla misma. Sin embargo, también demostramos que el grosor del parénquima puede estar relacionado negativamente con algunos organismos, especialmente los enemigos directos. Otras caracteristicas hipotéticas como defensivas (por ejemplo, proyecciones, coloración) pueden simplemente no desempeñar ningún papel.

Manipulation of host plant cells and tissues by gall-inducing insects and adaptive strategies used by different feeding guilds.

Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst this diversity. We discuss common themes that have emerged from our cytological and histochemical studies of diverse neotropical insect-induced galls. Gall initiation begins with recognition of reactive plant tissues by gall inducers, with subsequent feeding and/or oviposition triggering a cascade of events. Besides, to induce the gall structure insects have to synchronize their life cycle with plant host phenology. We predict that reactive oxygen species (ROS) play a role in gall induction, development and histochemical gradient formation. Controlled levels of ROS mediate the accumulation of (poly)phenols, and phytohormones (such as auxin) at gall sites, which contributes to the new cell developmental pathways and biochemical alterations that lead to gall formation. The classical idea of an insect-induced gall is a chamber lined with a nutritive tissue that is occupied by an insect that directly harvests nutrients from nutritive cells via its mouthparts, which function mechanically and/or as a delivery system for salivary secretions. By studying diverse gall-inducing insects we have discovered that insects with needle-like sucking mouthparts may also induce a nutritive tissue, whose nutrients are indirectly harvested as the gall-inducing insects feeds on adjacent vascular tissues. Activity of carbohydrate-related enzymes across diverse galls corroborates this hypothesis. Our research points to the importance of cytological and histochemical studies for elucidating mechanisms of induced susceptibility and induced resistance.

Illustrated and annotated checklist of Brazilian gall morphotypes.

The analysis on nine inventories on the richness and diversity of galling herbivores in Brazil accounted for 806 gall systems occurring in 443 host-plant species from 74 plant families. This checklist of the Brazilian gall morphotypes proposes seven standardized morphotypes and five additional shapes that group the majority of the three-dimensional shapes reported in literature. Criteria are proposed to standardize the terminology, and a critical analysis is provided aiming to avoid possible inconsistencies in order to generate easily comparable data in future inventories. The morphotypes are herein catalogued in alphabetical order, accompanied by a conceptual definition, an illustration, and examples that best represent the shape. It is proposed that the inventories should present at least the (1) host-plant species, (2) galling herbivore species or its identification to the lowest possible taxonomic level, (3) host-plant galled organ and gall position, (4) gall morphotype, (5) gall color and registration of indumentum when present, (6) gall phenological and developmental data, (7) association with other trophic levels, and (8) additional information, such as dimension, and number of chamber(s).

Quantitative computed tomography of the liver in dogs submitted to prednisone therapy / Tomografia computadorizada quantitativa do fígado de cães submetidos à terapia com prednisona

The aim of this study is to evaluate the possible alterations in radiodensity of the hepatic parenchyma and spleen resulting from the corticotherapy with prednisone, correlating these findings with serum biochemical hepatic transaminase activity. A clinical trial was performed on eight healthy dogs with the intent of evaluating possible hepatic alterations after prednisone therapy using quantitative computed tomography. All animals received prednisone orally at a dose of 2mg/kg of weight for 30 days. The radiodensity of the liver and spleen was determined before and after the period that the medication was administered. An increase in the radiodensity of the hepatic parenchyma between the initial and final experimental stages was observed. In the present study the existence of early hepatic alterations were verified, which are compatible with glycogen storage.

O objetivo deste estudo é avaliar as possíveis alterações na radiodensidade do parênquima hepático e esplênico decorrentes da corticoterapia com prednisona, correlacionando estes achados com níveis séricos de transaminase bioquímicas hepáticas. Um ensaio clínico foi realizado em oito cães sadios com o objetivo de avaliar possíveis alterações hepáticas após a terapia com prednisona por meio de tomografia computadorizada quantitativa. Todos os animais receberam prednisona por via oral na dose de 2mg / kg de peso por 30 dias. A radiodensidade do fígado e do baço foi determinada antes e após o período em que a medicação foi administrada. Foi observado aumento da radiodensidade do parênquima hepático entre os estágios iniciais e finais do experimento. No presente estudo, foi verificada a existência de alterações hepáticas precoces, que são compatíveis com o acúmulo de glicogênio.

Quantitative computed tomography of the renal cortex in healthy dogs and cats / Tomografia computadorizada quantitativa do córtex renal de cães e gatos hígidos

Este estudo caracteriza a radiodensidade do córtex renal de 10 cães e 10 gatos adultos, clinicamente saudáveis, por meio de exames de tomografia computadorizada helicoidal. Em cada rim, a radiodensidade renal foi estimada pelo valor médio das três regiões de interesse na região cortical, selecionados no polo cranial, polo caudal e hilo renal. A radiodensidade média do córtex renal nos cães e nos gatos foi, respectivamente, 28,4±4,7 e 22,4±3,6 unidades Hounsfield (HU). Verificou-se que os gatos possuem córtex renal hipoatenuante quando comparado com cães, um fato que está associado à maior deposição de conteúdo lipídico nos rins felinos. A diferença na radiodensidade encontrada entre o córtex renal de cães e de gatos é importante para uma correta interpretação dos achados renais no exame tomográfico.

A new gall-inducing genus and species of Eriococcidae (Hemiptera: Sternorrhyncha: Coccoidea) on Sapindaceae from Brazil.

A new gall-inducing genus and species of felt scales (Hemiptera: Coccoidea: Eriococcidae) found on the leaves and twigs of Matayba guianensis (Sapindaceae) in Brazil is described: Bystracoccus Hodgson gen n. and B. mataybae Hodgson, Isaias & Oliveira sp. n.  This is the first record of an eriococcid inducing leaf and stem galls on Sapindaceae and is only the second example of a member of the Eriococcidae to induce stem galls in which the insects diapause during the dry (winter) season.  Only the adult female, second-instar female and crawler are known.  The species overwinters as the first-instar nymph in pit galls on the twigs but spends the rest of the year associated with two-chambered galls on the leaves.  It has recently become clear that South America has a rich felt-scale insect fauna many of which induce galls. It has proved very difficult to place this new genus in a family as it appears to fall between the Eriococcidae and Beesoniidae but is here placed in the eriococcids based on the similarity of the first-instar nymphs and the abundance of this family in the Neotropics.  However, the dorsum of the abdomen of the mature adult female becomes heavily sclerotised, forming a round plug-like structure that completely fills the gall orifice.  This structure shows remarkable morphological similarities to that of the beesoniid Danumococcus parashoreae Takagi & Hodgson found on Parashorea tomentella (Dipterocarpaceae) in Sabah, Malaysia, with which it is compared along with other eriococcid genera known from South America.

Densitometria óssea em gatos hígidos por tomografia computadorizada quantitativa / Bone densitometry in healthy cats by quantitative computed tomography

Estabeleceram-se valores de média radiodensidade do osso trabecular das vértebras lombares de 16 gatos adultos, hígidos, por meio da tomografia computadorizada quantitativa (TCQ). O valor médio de radiodensidade do osso trabecular da segunda vértebra lombar foi de 436,1±42,1 unidades Hounsfield, com distribuição não homogênea da radiodensidade no corpo vertebral.

The radiodensity of the trabecular bone of the lumbar vertebrae in 16 healthy adult cats was studied using quantitative computed tomography (QCT). The average radiodensity of the trabecular bone of the second lumbar vertebra was 436.1±42.1 Hounsfield units. However, there was a nonhomogeneous radiodensity distribution of the vertebral body.

Utilização da tomografia computadorizada quantitativa como teste de resistência para avaliação de placas ósseas / Quantitative computed tomography as a test of endurance for evaluation of bony plates

Quantitative computed tomography was used to determine the radiodensity of bony plates. The CT scans provided information regarding radiodensity of bony plates and allowed to verify the uniformity of bone mineral density in their scope. The proposed methodology should be considered as another tool for determining the resistance of these biomaterials.

Detecção dos genes de Staphylococcus aureus, enterotoxinas e de resistência à meticilina em leite / Detection of genes of Staphylococcus aureus, enterotoxins and methicillin resistance in milk

Realizou-se a detecção do gene de Staphylococcus aureus, de enterotoxinas e de resistência à meticilina com extração de DNA feita diretamente de amostras de leite. Das 200 amostras estudadas, 145 (72,5%) amplificaram o gene femA, e estas foram analisadas quanto à presença dos genes sea, seb, sec e mecA. Os genes das enterotoxinas mais prevalentes foram: sea (60%), seb (37,9%) e sec (6,9%). Foram encontradas 18 amostras de leite (11,0 %) com S. aureus portadores do gene mecA. A detecção de S. aureus diretamente do leite, sem a necessidade de isolamento bacteriano e a caracterização do potencial enterotoxigênico, demonstra que a técnica de PCR é muito útil para estudos epidemiológicos das infecções estafilocócicas da glândula mamária. O alto percentual (72,5%) de amostras de leite positivas para a presença do gene femA sugere que S. aureus constitui um dos principais agentes causadores de infecções intramamárias na microrregião de Sete Lagoas-MG e que seu potencial enterotoxigênico e presença do gene mecA, que identifica o S. aureus resistente à meticlina, representa um risco potencial à saúde pública.

This work was performed to detect the Staphylococcus aureus gene, enterotoxins resistance to methicillin with the extraction of DNA directly from milk samples. Of the 200 samples studied 145 (72.5%) amplified the femA gene, which were analyzed regarding the presence of sea, seb, sec and mecA genes. The most prevalent enterotoxins genes were: sea (60%), seb (37.9%) and sec (6.9%). 18 milk samples (11 %) had S. aureus carrying the mecA gene. The detection of S. aureus directly from the milk, with no need for bacterial isolation and the characterization of the enterotoxigenic potential demonstrate that the PCR technique is very useful for epidemiological studies of staphylococcal infections of the mammary gland. The high percentage (72.5%) of positive milk samples for the presence of the femA gene suggests that S. aureus constitutes of the main agents which cause intramammary infections in the micro region of Sete Lagoas-MG and that its enterotoxigenic potential and the presence of the mecA gene, which identifies the S. aureus resistant to methicillin, represent a potential risk to public health.

Tomografia computadorizada no diagnóstico de hepatopatia esteroidal em cão: relato de caso / Computed tomography in the diagnosis of steroidal hepatopathy in a dog: case report

It is reported a case of an eight-year-old Yorkshire Terrier dog, with a history of prolonged use of prednisone in a dosage of 1mg/kg of body weight each 24 hours during two years. The helical computed tomography revealed hepatomegaly associated to a hyperattenuation of the parenchyma, with a radiodensity value of 82.55 Hounsfield units (HU). The spleen presented a mean radiodensity of 57.17HU, and a radiodensity difference of 25.38HU was observed between the two organs. Based on the history and findings of imaging technique, it was determined the presumptive diagnosis of steroidal hepatopathy compatible with accumulation of hepatic glycogen. It was concluded that computed tomography enabled the characterization of hepatic injury and the presumed diagnosis of steroidal hepatopathy.

Relata-se o caso de um cão da raça Yorkshire, de oito anos de idade, com histórico de tratamento com prednisona na dose de 1mg/kg de peso, a cada 24 horas, por dois anos. A tomografia computadorizada helicoidal revelou hepatomegalia associada à hiperatenuação, com radiodensidade de 82,55 unidades Hounsfield (HU). O baço apresentava radiodensidade média de 57,17HU, sendo observada diferença de radiodensidade de 25,38HU entre os dois órgãos. Por meio do histórico e dos achados da técnica de imagem, foi possível determinar o diagnóstico presuntivo de hepatopatia esteroidal compatível com acúmulo de glicogênio hepático. Concluiu-se que a tomografia computadorizada possibilitou caracterizar a lesão hepática e presumir o diagnóstico de hepatopatia esteroidal.

Analysis of the HLA population data (AHPD) submitted to the 15th International Histocompatibility/Immunogenetics Workshop by using the Gene[rate] computer tools accommodating ambiguous data (AHPD project report).

During the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), 14 human leukocyte antigen (HLA) laboratories participated in the Analysis of HLA Population Data (AHPD) project where 18 new population samples were analyzed statistically and compared with data available from previous workshops. To that aim, an original methodology was developed and used (i) to estimate frequencies by taking into account ambiguous genotypic data, (ii) to test for Hardy-Weinberg equilibrium (HWE) by using a nested likelihood ratio test involving a parameter accounting for HWE deviations, (iii) to test for selective neutrality by using a resampling algorithm, and (iv) to provide explicit graphical representations including allele frequencies and basic statistics for each series of data. A total of 66 data series (1-7 loci per population) were analyzed with this standard approach. Frequency estimates were compliant with HWE in all but one population of mixed stem cell donors. Neutrality testing confirmed the observation of heterozygote excess at all HLA loci, although a significant deviation was established in only a few cases. Population comparisons showed that HLA genetic patterns were mostly shaped by geographic and/or linguistic differentiations in Africa and Europe, but not in America where both genetic drift in isolated populations and gene flow in admixed populations led to a more complex genetic structure. Overall, a fruitful collaboration between HLA typing laboratories and population geneticists allowed finding useful solutions to the problem of estimating gene frequencies and testing basic population diversity statistics on highly complex HLA data (high numbers of alleles and ambiguities), with promising applications in either anthropological, epidemiological, or transplantation studies.

Comparative sterilization effectiveness of plasma in O2-H2O2 mixtures and ethylene oxide treatment.

We investigated the influence of variable parameters of plasma sterilization and compared its effectiveness with that of ethylene oxide using a reactive ion etching plasma reactor at 13.56 MHz. Gases tested were pure oxygen and oxygen-hydrogen peroxide mixtures in 190/10, 180/20, and 160/40 sccm ratios with constant gas flow at 200 sccm, pressure at 0.100 torr, radio-frequency power at 25 W, 50 W, 100 W, and 150 W, and temperature below 60 degrees C. Ethylene oxide sterilization was performed using 450 mg/L at 55 degrees C, 60% humidity, and -0.65 and 0.60 kgf/cm2 pressure. The biological indicator was Bacillus atrophaeus ATCC 9372, with exposure times of 3 to 120 min. Observed D values were 215.91, 55.55, 9.19, and 2.98 min for pure oxygen plasma at 25 W, 50 W, 100 W, and 150 W, respectively. Oxygen-hydrogen peroxide plasma produced D values of 6.41 min (190/10), 6.47 min (180/20), and 4.02 min (160/40) at 100 W and 1.47 min (190/10), 3.11 min (180/20), and 1.94 min (160/40) at 150 W. Ethylene oxide processes resulted in a D value of 2.86 min. Scanning electron microscopy analyses showed damage to the spore cortex.

Nd:YAG laser influence on tensile bond strength of self-etching adhesive systems.

OBJECTIVE: We evaluated the tensile bond strength of composite resin on enamel and dentine, treated with Nd:YAG laser before and after bonding procedures. BACKGROUND DATA: The use of laser radiation in dentistry is being developed day by day. One of the possible applications of dental lasers includes increasing the quality of self-etching bonding systems. METHODS: Forty-eight human teeth were used and separated into six groups: Group 1 (enamel control), Clearfil Liner Bond 2V (CLB 2V); group 2 (enamel), Nd:YAG + CLB 2V; group 3 (enamel), CLB 2V + Nd:YAG; group 4 (dentine control), CLB 2V; group 5 (dentine), Nd:YAG + CLB 2V; group 6 (dentine), CLB 2V + Nd:YAG. Tensile bond strength was performed. RESULTS: Enamel means (15,54) were lower than dentine means (20,38). Bond strength of laser before (15,73) was lower than laser after (20,65). Interaction results G1 x G3; G2 x G3; G4 x G1; G2 x G5 were statistically significant. CONCLUSIONS: Tensile bond strength of composites reached with self-etching adhesive systems were greater in dentine than in enamel. The best moment for application of Nd:YAG laser is after the use of adhesive system. Self-etching adhesive systems tested in this study can be used together with Nd:YAG laser without compromising to adhesion to dentine.

Nd:YAG laser influence on sound dentin bond strength.

OBJECTIVE: In the present study, the authors evaluated tensile bond strength of composite resin to dentin treated with Nd:YAG laser before and after bonding procedures. SUMMARY BACKGROUND DATA: Lasers have been widely used in dentistry and have contributed to the development of new technologies. Adhesive systems have been indicated for most dental procedures and have produced good results. Studies concerned with the combined use of this adhesive system was the subject of this study. METHODS: Thirty noncarious human anterior teeth, freshly extracted, for periodontal reasons, were used. After grinding the buccal dentinal surface until its exposition, specimens were separated into three groups and received the following treatments: (group 1) control--acid etching plus primer plus bond; (group 2) laser plus acid etching plus primer plus bond; (group 3) acid etching plus primer plus bond plus laser. Specimens of composite resin (Z100, 3M, Saint Paul, MN) were constructed on an inverted truncated 3-mm diameter cone mold. Tensile bond strength was performed using Inströn Universal machine, at 0.5 mm/min speed. RESULTS: Analysis of variance (ANOVA) (p < 0.05) determined that the type of dentinal treatments used had an influence on tensile bond strength. Tukey's test, however, showed that group 1 (15.46) and 3 (15.67) had similar results both of which were higher than group 2 (4.57). CONCLUSIONS: Based on the results obtained, one can conclude that group 1 (without laser) and group 3 (laser after bonding) had similar results, both higher than those observed for group 2 (laser before bonding). These results indicate that more research is needed about how a hybrid layer is formed when laser radiation is used.