Antileishmanial activity and immunomodulatory effect of secosubamolide, a butanolide isolated from Nectandra oppositifolia (Lauraceae)

Visceral leishmaniasis is a complex neglected tropical disease caused by Leishmania donovani complex. Its current treatment reveals strong limitations, especially high toxicity. In this context, natural products are important sources of new drug alternatives for VL therapy. Therefore, the antileishmanial and immunomodulatory activity of compounds isolated from Nectandra oppositifolia (Lauraceae) was investigated herein. Methods: The n-hexane extract from twigs of N. oppositifolia were subjected to HPLC/HRESIMS and bioactivity-guided fractionation to afford compounds 1 and 2 which were evaluated in vitro against Leishmania (L.) infantum chagasi and NCTC cells. Results: The n-hexane extract displayed activity against L. (L.) infantum chagasi and afforded isolinderanolide E (1) and secosubamolide A (2), which were effective against L. (L.) infantum chagasi promastigotes, with IC50 values of 57.9 and 24.9 µM, respectively. Compound 2 was effective against amastigotes (IC50 = 10.5 µM) and displayed moderate mammalian cytotoxicity (CC50 = 42 µM). The immunomodulatory studies of compound 2 suggested an anti-inflammatory activity, with suppression of IL-6, IL-10, TNF with lack of nitric oxide. Conclusion: This study showed the antileishmanial activity of compounds 1 and 2 isolated from N. oppositifolia. Furthermore, compound 2 demonstrated an antileishmanial activity towards amastigotes associated to an immunomodulatory effect.(AU)

Neolignans isolated from twigs of Nectandra leucantha Ness & Mart (Lauraceae) displayed in vitro antileishmanial activity

The therapeutic arsenal for the treatment of Leishmaniasis is limited and includes toxic compounds (antimonials, amphotericin B, pentamidine and miltefosine). Given these aspects, the search for new compounds based on floristic biodiversity is crucial. In the present work, we report the isolation, characterization and antileishmanial activity of six related neolignans (1­6) of bioactive extract from Nectandra leucantha (Lauraceae) twigs. Methods: Dried and powdered twigs of N. leucantha were exhaustively extracted using n-hexane. The crude extract was dereplicated by HPLC/HRESIMS and subjected to column chromatography to yield pure compounds 1­6. Their chemical structures were identified via NMR and comparison of obtained data with those previously published in the literature. Biological assays of compounds 1­6 and their respective monomers (eugenol and methyleugenol) were performed using promastigote and amastigote forms of Leishmania (L.) infantum. Results: Dereplication procedures followed by chemical characterization of isolated compounds by NMR enabled the identification of related neolignans 1­6. Neolignans 2, 4 and 6 showed potential against amastigote forms of L. (L.) infantum (EC50 values of 57.9, 67.7 and 13.7 µM, respectively), while compounds 1 and 3 were inactive. As neolignans 2­4 are chemically related, it may be suggested that the presence of the methoxyl group at C4 constitutes an important structural aspect to increase antileishmanial potential against amastigote forms. Compound 6, which consists of a methylated derivative of compound 5 (inactive) showed antileishmanial activity similar to that of the standard drug miltefosine (EC50 =16.9 µM) but with reduced toxicity (SI = 14.6 and 7.2, respectively). Finally, two related monomers, eugenol and methyleugenol, were also tested and did not display activity, suggesting that the formation of dimeric compounds by oxidative coupling is crucial for antiparasitic activity of dimeric compounds 2, 4 and 6. Conclusion: This study highlights compound 6 against L. (L.) infantum amastigotes as a scaffold for future design of new compounds for drug treatment of visceral leishmaniasis.(AU)

Composición química del aceite esencial de Ocotea cymbarum Kunth (cascarillo y/o sasafrás) de la región Orinoquia / Chemical composition of essential oil of Ocotea cymbarum Kunth (cascarilla and/or sassafras) from the Orinoquía region

Introducción: en algunas poblaciones de la Orinoquia colombiana y/o venezolana venden, en plazas de mercado, los aceites de cascarillo y sasafrás; estos aceites son empleados para aliviar dolencias como artritis reumática, afecciones respiratorias y tratar picaduras de insectos y animales ponsoñosos. Los productos se obtienen de la especie Ocotea cymbarum Kunth, la cual tiene una abundante sinonimia botánica como Alseodaphne cymbarum,Licaria cymbarum, Misanteca cymbarum, Nectandra barcellensis, Nectandra cymbarum, Nectandra elaiophora, Nectandra oleífera y Ocotea barcellensis. Objetivo: realizar un análisis comparativo de las características fisicoquímicas del aceite esencial de cascarillo y/o sasafrás (posible Ocotea cymbarum Kunth). Métodos: la composición química relativa de los aceites obtenidos de madera y corteza fue determinada mediante cromatografía de gases acoplada a espectrometría de masas (CG-EM), el cálculo y comparación de índices de retención en columnas de polaridad ortogonal y la comparación de los espectros de masas por impacto electrónico con los de las bases de datos NIST08.L, Wiley9.L. Resultados: fueron determinados 45 compuestos en las muestras analizadas y más del 90 por ciento de la composición relativa establecida para cada aceite corresponde a compuestos monoterpénicos principalmente alcanfor y alfa-terpineol. Al realizar un análisis de las rutas biosintéticas que conducen a la generación de los principales compuestos detectados en los aceites analizados, se evidenció que las especies de donde se obtuvieron estos aceites, presentan diferentes grados de evolución micromolecular. Conclusión: los aceites de cascarillo y sasafrás provienen de especies vegetales con diferentes grados de evolución química. Este resultado refuerza la evidencia de la alta diversidad biológica de la familia Lauraceae. El trabajo fue realizado con el apoyo financiero del Laboratorio de Productos Naturales Vegetales del departamento de Química de la Universidad Nacional de Colombia sede Bogotá(AU)

Introduction: cascarilla and sassafras oils are sold in market places of some settlements in the Colombian and/or Venezuelan Orinoquía. These oils are used to alleviate conditions such as rheumatoid arthritis and respiratory disorders, and to treat the bites of insects and poisonous animals. The oils are obtained from the species Ocotea cymbarum Kunth, which displays abundant botanical synonymy as Alseodaphne cymbarum, Licaria cymbarum,Misanteca cymbarum, Nectandra barcellensis, Nectandra cymbarum, Nectandra elaiophora, Nectandra oleífera and Ocotea barcellensis. Objective: carry out a comparative analysis of the physicochemical characteristics of essential oil of cascarilla and/or sassafras (Ocotea cymbarum Kunth).Methods: the relative chemical composition of oils obtained from wood and bark was determined by gas chromatography coupled with mass spectrometry (GC-MS). Estimation and comparison of retention indices was conducted with orthogonal polarity columns. Comparison of electron impact mass spectra was performed with the databases NIST08.L and Wiley9.L. Results: forty-five compounds were determined from the samples analyzed. More than 90 percent of the relative composition established for each oil corresponds to monoterpenic compounds, mainly camphor and alpha-terpineol. Analysis of the biosynthetic pathways leading to the generation of the main compounds detected in the oils studied, showed that the species from which the oils were obtained exhibit varying degrees of micromolecular evolution. Conclusion: cascarilla and sassafras oils are obtained from plant species at varying stages of chemical evolution. This result constitutes additional evidence of the great biological diversity of the Lauraceae family. The study was conducted with financial support from the Natural Plant Products Laboratory of the Chemistry Department at the National University of Colombia at Bogotá(AU)

Effect of (+)-dehydrofukinone on GABAA receptors and stress response in fish model

(+)-Dehydrofukinone (DHF) is a major component of the essential oil of Nectandra grandiflora (Lauraceae), and exerts a depressant effect on the central nervous system of fish. However, the neuronal mechanism underlying DHF action remains unknown. This study aimed to investigate the action of DHF on GABAA receptors using a silver catfish (Rhamdia quelen) model. Additionally, we investigated the effect of DHF exposure on stress-induced cortisol modulation. Chemical identification was performed using gas chromatography-mass spectrometry and purity was evaluated using gas chromatography with a flame ionization detector. To an aquarium, we applied between 2.5 and 50 mg/L DHF diluted in ethanol, in combination with 42.7 mg/L diazepam. DHF within the range of 10-20 mg/L acted collaboratively in combination with diazepam, but the sedative action of DHF was reversed by 3 mg/L flumazenil. Additionally, fish exposed for 24 h to 2.5-20 mg/L DHF showed no side effects and there was sustained sedation during the first 12 h of drug exposure with 10-20 mg/L DHF. DHF pretreatment did not increase plasma cortisol levels in fish subjected to a stress protocol. Moreover, the stress-induced cortisol peak was absent following pretreatment with 20 mg/L DHF. DHF proved to be a relatively safe sedative or anesthetic, which interacts with GABAergic and cortisol pathways in fish.

Genus Nectandra: phytochemistry and biological activity / Género Nectandra: fitoquímica y actividad biológica

The genus Nectandra belongs to the Ocotea complex and these species (Nectandra) are generally trees. It is considered endemic in the Neotropics. This genus has been reported uses in folk medicine as antifungal, anti-inflammatory, antimalarial, analgesic, treatment of ulcers, and febrifuge, among others; have also been reported some biological activity assays including: antitumor and antimalarial activity, activity against cardiovascular disease, among others. The genus Nectandra contains different secondary metabolites and they have been reported: Alkaloids; such as aporfinic, proaporfin, benzylisoquinoline, bisbenzylisoquinoline, and morfinandienone-type; lignans and neolignans, furofuran, benzofuran, tetrahydrofuran and dihydrofuran, and 3,3-neolignans-type; terpenes and sesquiterpenoid (monocyclic and bicyclic); Phytosterols and derived from those (3-hydroxy and the 3-ketone pentacyclic compounds); flavonoids, particularly O- glycosylated; xanthones, phenolic acids, polyalcohol, and alkene-alkyne, especially rubrenolide and rubrynolide.

El género Nectandra pertenece al complejo Ocotea y estas especies (Nectandra) son por lo general árboles. Se considera endémica en el Neotrópico. Este género se ha informado de usos en medicina popular como antifúngico, anti-inflamatorio, antimalárico, analgésico, el tratamiento de las úlceras, y febrífugo, entre otros; También se han informado de algunos ensayos de actividad biológica, incluyendo: antitumoral y actividad antipalúdica, actividad contra las enfermedades cardiovasculares, entre otros. El género Nectandra contiene diferentes metabolitos secundarios y se han reportado alcaloides; tales como aporfinas, proaporfina, benzylisoquinolina, y del tipo morfinandienona; lignanos y neolignanos, furofuran, benzofurano, tetrahidrofurano y dihidrofurano, y del tipo 3,3-neolignanos; terpenos y sesquiterpenoide (monocíclicos y bicíclicos); Los fitoesteroles se derivan de aquellos (3-hidroxi y los compuestos pentacíclicos 3-cetona); flavonoides, particularmente O-glicosilada; xantonas, ácidos fenólicos, polialcohol, y alqueno-alquino, especialmente rubrenolide y rubrynolida.

Nectandra falcifolia: potential phytopharmaceutical for skin damage protection designed by statistical approach and characterized by photoacoustic spectroscopy

AbstractPhytopharmaceutical products are being used in the treatment and prevention of health problems. Nowadays, the development and evaluation of novel pharmaceutical products is expensive and time consuming. A statistical approach is a good tool for optimal development processes. Nectandra falcifolia (Nees) J.A. Castigl. ex Mart. Crov. & Piccinini, Lauraceae, a Brazilian species, is reported as anti-inflammatory, anti-leishmanial and anti-microbial. However, there is little known about its chemical composition. For other species of Nectandra genus, the presence of antioxidant compounds is reported. In order to optimize the process of obtaining extract with high antioxidant activity, different extraction conditions were tested following a statistical approach. Two sequential experimental designs were used – first, a factorial 23 design, followed by central composite 22. The extracts manufactured by these experimental statistical matrixes had their antioxidant activity and phenolic contents quantified and the response surface plots were fitted in quadratic models and they predicted the best extraction condition for the best antioxidant activity. This standardized extract and its antioxidant activity were better evaluated by two complementary tests (ABTS and Burst respiratory). A topical formulation containing 1% (w/w) of standardized extract was prepared and used for an in vivo skin permeation study using a two-dose application. The photoacoustic spectroscopy was used to analyze the samples from the permeation study and the composition profile of standardized extract. In rat skin samples, the data demonstrated that for the higher dose of topical formulation (5 g/cm2), the standardized extract could cross skin and be seen in epidermis and dermis. This was not the case for the lower dose (2 g/cm2) which was only present in the epidermis. This information suggests that this novel standardized extract of N. falcifoliacould be explored for skin damage prevention or treatment for diseases developed by oxidative damage.

Variabilidad de la composición química del aceite esencial de nectandra megapotamica (spreng. ) mez (lauraceae) / Variability of chemical composition of essential oil from nectandra megapotamica (spreng. ) mez (lauraceae)

Este trabajo describe la variabilidad química del aceite esencial (AE) de N. megapotamica, utilizando análisis multivariado. Se colectaron hojas de tres individuos en una población en Santa Maria, Brasil, en cada estación durante un año y se clasificaron en hojas jóvenes y viejas. Los AE se obtuvieron por hidrodestilación y la composición química fue determinada por cromatografía de gases acoplada a espectrometría de masas. Se realizó un análisis de agrupamiento jerárquico para formación de grupos químicos (GQ) y análisis de componentes principales (ACP) para verificar cuáles constituyentes influenciaron la formación de grupos. Inicialmente se observaron dos agrupamientos en el dendrograma debido a concentraciones de α-pineno y biciclogermacreno, constituyentes mayoritarios. En el segundo corte se discriminaron cinco GQ, siendo este también el número de componentes principales con valores propios superiores a 1. Los isómeros de asarona se observaron solamente en el AE de dos individuos (GQ5), constituyendo los principales elementos de diferenciación.

This work describes the chemical variability of the essential oils (EO) of N. megapotamica using multivariate analysis. Leaves of three individuals of a population in Santa Maria-RS were collected per season for a year, and classified into young and old. The EO were obtained by hydrodistillation and the chemical composition was determined by gas chromatography coupled to mass spectrometry (GC/MS). Cluster analysis (HCA) were performed for formation of chemical groups (CG), and principal component analysis was done (PCA) to determine which constituents influenced the formation of groups. Initially, two clusters were observed in the dendrogram, due to the concentration of α-pinene and bicyclogermacrene, major constituents of the EO. The second section showed five different CG, which is also the number of principal components with eigenvalues greater than 1. The occurrence of isomers of asarone was observed only in EO of two individuals (CG5), containing the main elements of differentiation.

Lignanos diarildimetilbutanos y otros constituyentes aislados de nectandra turbacensis (kunth) nees (lauraceae) / Diaryldimethylbutane lignans and other constituents isolated from nectandra turbacensis (kunth) nees (lauraceae) / Lignanas diaryldimethylbutane e outros constituintes isolado de nectandra turbacensis (kunth) nees (lauraceae)

Ocho compuestos conocidos fueron aislados del extracto etanólico de corteza de Nectandra turbacensis (Kunth) Nees (Lauraceae). Éstos fueron identificados como ácido meso-dihidroguayarético 1, ácido treo-dihidroguayarético 2, sauriol B 3, y treo-austrobailignano-6 4; vitexina (8-C-β-D-glucopiranosil-5,7,4'-trihidroxiflavona) 5; estigmast-4-en-3-ona 6 y la mezcla sitosterol 7 / estigmasterol 8. Las estructuras de los compuestos fueron elucidadas por métodos espectroscópicos, que incluyeron técnicas de RMN en 1D y 2D, CG/EM y por comparación de los datos espectroscópicos, reportados en la literatura, de compuestos relacionados. Este es el primer reporte de la presencia de este tipo de compuestos en la especie. Se describen también las implicaciones quimiotaxonómicas; relacionadas con la presencia frecuente de lignanos en especies del género Nectandra.

Eight known compounds were isolated from the ethanol extract of bark Nectandra turbacensis (Kunth) Nees (Lauraceae); which were identified as meso-dihydroguaiaretic acid 1, threo-dihidroguaiaretic acid 2, sauriol B 3, and threo-austrobailignan-6 4; vitexin (8-C-β-D-glucopyranosyl-5,7,4'-trihydroxyflavone) 5; stigmast-4-en-3-one 6; and sitosterol 7/ stigmasterol 8 mixture. The structures of the compounds were elucidated by spectroscopic methods, techniques involving 1D and 2D NMR, GC/MS and by comparison of spectral data, reported in the literature, of related compounds. This is the first report of the presence of such compounds in the species. The chemotaxonomic implications are also described; related to the frequent presence of lignans in the genus Nectandra.

Oito compostos conhecidos foram isolados do extrato etanólico da casca de Nectandra turbacensis (Kunth) Nees (Lauraceae). Quais foram identificados como ácido meso-dihidroguayarético 1, ácido treo-dihidroguayarético 2, sauriol B 3, e treo-austrobailignano-6 4; vitexina (8-C-β-D-glucopiranosil-5,7,4'-trihidroxiflavona) 5; estigmast-4-en-3-ona 6 e mistura sitosterol 7/ estigmasterol 8. As estruturas dos compostos foram determinadas por métodos espectroscópicos, técnicas que envolvem a 1D e 2D RMN, CG/EM e a comparação dos dados espectroscópicos, relatados na literatura, compostos relacionados. Este é o primeiro relato da presença de tais compostos na espécie. As implicações quimiotaxonômicos também são descritos; relacionada com a presença freqüente de lignanas no gênero Nectandra.

Validación etnofarmacológica de Nectandra coriacea (Sw) Griseb y Caesalpinia bahamensis Lam reportadas como diuréticas en el municipio Santa Clara / Ethnopharmacological validation of Nectandra coriacea (Sw.) Griseb. and Caesalpinia bahamensis Lam reported as diuretics in Santa Clara municipality

En Cuba se reportan alrededor de 179 plantas que la población utiliza como diuréticas, pero en la mayoría de los casos este efecto no ha sido comprobado experimentalmente. Objetivo: comprobar el efecto farmacológico atribuido a plantas medicinales reportadas como diuréticas que carecen de validación experimental. Métodos: se realizó un estudio etnofarmacológico en el municipio Santa Clara que contó con 2 etapas: identificación etnofarmacológica y evaluación in vivo de la actividad diurética de las plantas más reportadas que carecían de validación preclínica. La investigación etnofarmacológica se desarrolló en varias localidades del referido municipio, utilizando una muestra heterogénea conformada por diferentes grupos muestrales. A partir de las dos especies identificadas que carecían de validación experimental, se elaboraron decocciones al 30 por ciento y se administraron por vía oral a la dosis de 400 mg/kg, sobre la base de la determinación de los sólidos totales, a ratas albinas machos con un peso comprendido entre 170 y 210 g. La dosis fue completada con solución salina fisiológica para lograr una sobrecarga hidrosalina con un volumen total de administración constante de 40 mL/kg PV, tanto para los grupos tratados como para los controles (positivo, furosemida 20 mg/kg e hidroclorotiazida 10 mg/kg; negativo, cloruro de sodio 0,9 por ciento). Se midieron los volúmenes de orina excretados a las ½, 1, 2, 3, 4, 5 y 6 h posadministración y las concentraciones de electrolitos (Na+ y K+) en la orina total colectada a ls 24 h...

There are in Cuba about 179 plants that the population uses as diurectics, but the effect of the majority of them has not been experimentally confirmed. Objective: to verify the pharmacological effect attributed to medicinal plants reported as diuretics, whose effect has not been validated yet. Methods: a two-phase ethnopharmacological study was conducted in Santa Clara municipality: ehnopharmacological identification and in vivo evaluation of the diuretic action of the most reported plants whose preclinical validation was not confirmed. The ethnopharmacological research study was developed in several places of the refered municipality, using a heterogenous sample made up of different sampling groups. On the basis of the two identified species that have not been experimentally validated, 30 percent decoctions were prepared and orally administered at a dose of 400 mg/kg, based on the determination of total solid content, to male albine rats weighing 170 to 210 g. The dose was completed with physiological saline solution to reach hydrosaline overload with constant total volume of administration equals to 40 mL/kg PV for both the treated groups and the controls (positive, furosemide at 20 mg/kg and hydrochlorotiazide at 10 mg/kg, and negative controls, 0,9 percent sodium chloride). Excreted urine volumen were measured at half and hour, one hour, 2, 3, 4, 5 and 6 hours after the administration and the electrolyte concentrations in the total collected urine at 24 hours...

Aspectos biológicos e morfologia externa dos imaturos de Memphismoruus stheno (Prittwitz) (Lepidoptera: Nymphalidae) / Biological aspects and external morphology of immature stages of Memphis moruus stheno (Prittwittz) (Lepidoptera: Nymphalidae)

Immature stages of Memphis moruus stheno (Prittwittz) were subject of a behavior, biological and morphological study. The morphological study was carried out through observation by stereoscopic microscopy with camera lucida and micrometric lens attached for illustrations and measurements, respectively; and scanning electron microscopy for ultrastructural analysis. Behavioral data were obtained through direct observation in the field and laboratory. Eggs were laid on the underside of leaves of two Lauraceae species. The first to third instars build frass chains, the fourth and the fifth instars build a conical shelter using a single leaf of the host plant. Before pupation, larvae bend its body ventrally and the pupae are incapable of movement. Descriptions, illustrations and photographs of egg, all five instars and pupa are given. The cephalic morphology and chaetotaxy of first instar were described and illustrated. Results are compared with other Charaxinae immature stages.

Experimental models using radionuclides for assessment of the effects of natural drugs

The aim of this study was to evaluate the effect of the extracts of Nectandra membranacea (N. membranacea), Ginkgo biloba (EGb) and Passiflora (PEF) on the morphology of red blood cells (RBC), on the biodistribution of sodium pertechnetate (99mTcO4Na), on the morphology of duodenum and on the labeling of blood constituents (BC, IF-P, IF-BC) with technetium-99m (Tc-99m). Morphometry studies also were performed. The results show that EGb promotes alteration of the labeling of BC, IF-P and IF-BC (p<0.05). The N. membranacea extract does not promote significant alteration of the radiolabeling, and PEF extract alters the IF-P labeling. N. membranacea, EGb and PEF extracts were able to alter the RBC morphology (P<0.05). N. membranacea extract and EGb modifies the biodistribution of the 99mTcO4Na, and EGb influences the morphometry of duodenum isolated from rats (P<0.05).

O objetivo deste estudo foi avaliar o efeito de um extrato de Nectandra (N. membranacea), de Ginkgo (EGb) e de Passiflora e. flavicarpa (PEF) na marcação de constituintes sanguíneos (BC, IF-P, IF-BC) com Tc-99m, na morfologia de hemácias (RBC), na biodistribuição do 99mTcO4Na na morfologia do duodeno. Amostras de sangue foram incubadas com os extratos. Tc-99m foi adicionado e as frações do plasma (IF-P) e da célula (IF-BC) foram isoladas. Estudos morfométricos foram realizados. Os resultados mostram que EGb promove alteração na marcação de BC, IF-P e IF-BC. N. membranacea não altera a radiomarcação e PEF altera a marcação de IF-P. O extrato de N. membranacea, EGb e PEF alteraram a morfologia de RBC (p<0.05). Os extratos de N. membranacea e EGb modificam a biodistribuição do 99mTcO4Na, e o EGb influencia a morfometria (p<0.05) do duodeno de ratos.

Identificação de plantas hospedeiras da broca do abacate, Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) no Rio Grande do Sul / Identification of host plants of the avocado borer, Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) in Rio Grande do Sul

Frutos de Nectandra megapotamica Mez e de Cinnamomum camphora (L.) (Lauraceae) foram coletados no Rio Grande do Sul, em 2004. Nove espécies pertencentes a cinco famílias de insetos foram coletadas: duas espécies de Drosophila (Diptera: Drosophilidae), seis espécies de Coleoptera: Heilipus sp. e Conotrachelus sp. (Curculionidae), Hypothenemus sp. (Scolytidae) e três espécies de Carpophilus (Nitidulidae), e uma de Lepidoptera (Elachistidae). Os espécimes pertencentes à família Elachistidae foram identificados como Stenoma catenifer Walsingham, a broca do abacate. S. catenifer emergiu do início de abril até meados de maio. A infestação nos frutos foi baixa. Duas novas plantas hospedeiras dessa praga foram identificadas.

Fruits of Nectandra megapotamica Mez and Cinnamomum camphora (L.) (Lauraceae) were collected in Rio Grande do Sul, Brazil, in 2004. Species of five families of insects were found inside the fruits: two fly species (Diptera: Drosophilidae: Drosophila spp.), six beetle species, Heilipus sp., Conotrachelus sp. (Curculionidae), Hypothenemus sp. (Scolytidae) and three species of Carpophilus (Nitidulidae), and moths (Lepidoptera: Elachistidae). The moth especimes were identified as Stenoma catenifer Walsingham, the avocado borer. The occurrence of the moth was predominant from early April until middle May. The natural larval infestation level was low. Two new host plant of the pest were identified.

Estructura poblacional y relaciones ambientales del árbol tropical Nectandra rudis (Lauraceae), una especie rara en el occidente de México / Population structure and environmental relationships of the tropical tree Nectandra rudis (Lauraceae), a rare species in western Mexico

Population structure and environmental relationships of the tropical tree Nectandra rudis (Lauraceae), a rare species in western Mexico. The tree N. rudis is a rare species from western Mexico of which community and population features are unknown. We studied a population in an altitudinal gradient, from 550-1,850 m above sea level in the Sierra de Manantlan, Jalisco, Mexico. We established four 60x48 m sample sites at vertical distances of 100 m along this altitudinal gradient. Within each plot, ten 100 m2 circular sub-sampling units were randomly located. At each unit, we recorded diameter at breast height (dbh) and tree height for all woody vegetation > or =2.5 cm dbh. Basal area, tree density, frequency, species richness and importance values per species and plot. We estimated the vertical structure (total tree height) and diameter( as M=5log(10)N) for all N. rudis individuals. A direct ordination through Canonical Correspondence Analysis was done, involving amongst other species, edaphic and environmental data matrices. The record of 44 N. rudis individuals, in seven out the 56 plots sampled, represents the most septentrional record for the species and the first in Western Mexico. Its density and basal area represented 4.5 % and 8.7 % respectively of the total estimated for the community. The greatest importance values were observed at 1 650 m above sea level. The population structure of N. rudis is structured into five diameter categories in an inverse "J" shaped distribution. This is a typical behavior observed to occur in the Lauraceae, which produces big seeds of short viability that germinate when there is high soil moisture content. The species tend to form dense seedling banks although only a reduced number of them are able to survive. Species richness varies from 27 to 39 at plot level; the greatest importance values for the plots on which N. rudis was found, corresponds to Urera verrucosa (Liebm.) V.W. Steinm., N. rudis, Ficus sp...

Nectandra rudis es una especie rara en el occidente de México. Analizamos la población y la comunidad donde se desarrolla, en la Sierra de Manantlan, Jalisco, México. Establecimos cuatro parcelas de 60x48 m con diferencias altitudinales de 100 m entre sí. En cada una seleccionamos aleatoriamente diez círculos de 100 m2 cada uno, en los cuales medimos los diámetros normales y las alturas de las especies leñosas con diámetro ≥2.5 cm. Para cada especie y por parcela determinamos el área basal, la densidad, la frecuencia, la riqueza de especies y los valores de importancia. Establecimos la estructura vertical y diamétrica de N. rudis. Hicimos una ordenación directa con la matriz de especies y las variables edáficas y ambientales. El registro de N. rudis en la Sierra de Manantlán representa el primer registro para el occidente de México y el más septentrional del taxon. La población se estructura en cinco categorías diamétricas y genera una curva en forma de “J” invertida. La riqueza de especies en las parcelas donde se encuentra N. rudis, varía de 27 a 39, y los mayores valores de importancia son para Urera verrucosa, N. rudis y Ficus sp. La ordenación directa permite postular a la presencia de árboles caídos, la cobertura, la profundidad del horizonte superficial y el magnesio soluble, como los factores ambientales de mayor influencia en la distribución y abundancia de N. rudis.

The ingestión of a Nectandra membran cea extract changes the bioavailability of technetium-99m radiobiocomplex in rat organs

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membran cea extract on the bioavailability of the sodium pertechnetate (Na99mTc0(4)) radiobiocomplex in rat organs. The animals were treated with a N. membran cea extract (30 mg/ ml), for 6 days. Na99mTc0(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ ( percentATI/organ). The percentATI/organ was divided by the mass of each organ to calculate the percentATI/g. A significant increase of the percentATI/organ of Na99mTc0(4) was observed in muscle and thyroid as well as in the percentATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na99mTc0(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb.