Fumigant toxicity and biochemical effects of selected essential oils toward the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae).

Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) is an insect popularly known as the red flour beetle, it is widely distributed worldwide and can cause serious damage to stored grains. Chemical control is the most used method for managing this pest, however, some substances are toxic to mammals and the environment. Therefore, the development of new effective and safe insecticides is necessary. Essential oils (EOs) can be considered as a potential alternative in the development of pesticides due to their physicochemical properties and varied effects against insects. In the current study, was determined the fumigant toxicity and biochemical effects of selected essential oils against T. castaneum. The 23 selected EOs were characterized by GC-MS and their fumigant lethal concentrations were determined. An exploratory Cluster analysis was performed to find a relationship between fumigant toxicity and chemical composition. Finally, the inhibition of the catalytic activity of acetylcholinesterase (AChE), glutathione S-transferase (GST) and catalase (CAT) was evaluated using protein homogenates obtained from T. castaneum. The results indicated that EOs with the highest fumigant potential were those with greater diversity in their composition, while the least active EOs presented mainly monoterpenes. The most active EOs were those obtained from Foeniculum vulgare and Zanthoxylum monophyllum with LC50 values of 16.23 and 18.54 µL/L air respectively. Regarding the inhibition of the enzymatic activity of the 23 EOs evaluated at 500 µL/L, only two caused an inhibition greater that 50% on AChE, which corresponded to EOs from Piper nigrum and Rosmarinus officinalis. Likewise, EOs from C. sinensis, Piper aduncum and Zanthoxylum monophyllum were the only ones able to inhibiting GST activity by more than 50%. Respecting CAT inhibition, 7 EOs caused and inhibition greater than 50%, highlighting those from Lavandula angustifolia, C. sempervirens and Eucalyptus sp. These results show that the EOs evaluated in this study seems to be a promising bio-controller of T. castaneum since have high fumigant toxicity and exert different mechanisms of action.

Effects of Essential Oils from 24 Plant Species on Sitophilus zeamais Motsch (Coleoptera, Curculionidae).

Chemical control of the maize weevil (Sitophilus zeamais) has been ineffective and presents serious collateral damage. Among plant-derived insecticides, essential oils (EOs) are suitable candidates to control this stored products pest. In this work, the insecticidal activities of 45 natural EOs against S. zeamais adults were screened, and the most promising ones (24 EOs) were characterized by GC-MS. The repellent and toxic effects (contact and fumigant) of these 24 EOs were determined, and by a cluster analysis they were classified into two groups considering its fumigant activity and contact toxicity. For the EOs with the highest fumigant potential (14 oils) and their main active constituents (17 compounds), lethal concentrations were determined. The most active EOs were those obtained from L. stoechas and L. alba, with LC50 values of 303.4 and 254.1 µL/L air and characterized by a high content of monoterpenes. Regarding the major compounds, the oxygenated monoterpenes R-(+)-pulegone (LC50 = 0.580 mg/L air), S-(-)-pulegone (LC50 = 0.971 mg/L air) and R-(-)-carvone (LC50 = 1.423 mg/L air) were the most active, as few variations in their concentrations significantly increased insect mortality.

Hematocrit Measurement with R2* and Quantitative Susceptibility Mapping in Postmortem Brain.

BACKGROUND AND PURPOSE: Noninvasive venous oxygenation quantification with MR imaging will improve the neurophysiologic investigation and the understanding of the pathophysiology in neurologic diseases. Available MR imaging methods are limited by sensitivity to flow and often require assumptions of the hematocrit level. In situ postmortem imaging enables evaluation of methods in a fully deoxygenated environment without flow artifacts, allowing direct calculation of hematocrit. This study compares 2 venous oxygenation quantification methods in in situ postmortem subjects. MATERIALS AND METHODS: Transverse relaxation (R2*) mapping and quantitative susceptibility mapping were performed on a whole-body 4.7T MR imaging system. Intravenous measurements in major draining intracranial veins were compared between the 2 methods in 3 postmortem subjects. The quantitative susceptibility mapping technique was also applied in 10 healthy control subjects and compared with reference venous oxygenation values. RESULTS: In 2 early postmortem subjects, R2* mapping and quantitative susceptibility mapping measurements within intracranial veins had a significant and strong correlation (R2 = 0.805, P = .004 and R2 = 0.836, P = .02). Higher R2* and susceptibility values were consistently demonstrated within gravitationally dependent venous segments during the early postmortem period. Hematocrit ranged from 0.102 to 0.580 in postmortem subjects, with R2* and susceptibility as large as 291 seconds-1 and 1.75 ppm, respectively. CONCLUSIONS: Measurements of R2* and quantitative susceptibility mapping within large intracranial draining veins have a high correlation in early postmortem subjects. This study supports the use of quantitative susceptibility mapping for evaluation of in vivo venous oxygenation and postmortem hematocrit concentrations.

Cognitive Implications of Deep Gray Matter Iron in Multiple Sclerosis.

BACKGROUND AND PURPOSE: Deep gray matter iron accumulation is increasingly recognized in association with multiple sclerosis and can be measured in vivo with MR imaging. The cognitive implications of this pathology are not well-understood, especially vis-à-vis deep gray matter atrophy. Our aim was to investigate the relationships between cognition and deep gray matter iron in MS by using 2 MR imaging-based iron-susceptibility measures. MATERIALS AND METHODS: Forty patients with multiple sclerosis (relapsing-remitting, n = 16; progressive, n = 24) and 27 healthy controls were imaged at 4.7T by using the transverse relaxation rate and quantitative susceptibility mapping. The transverse relaxation rate and quantitative susceptibility mapping values and volumes (atrophy) of the caudate, putamen, globus pallidus, and thalamus were determined by multiatlas segmentation. Cognition was assessed with the Brief Repeatable Battery of Neuropsychological Tests. Relationships between cognition and deep gray matter iron were examined by hierarchic regressions. RESULTS: Compared with controls, patients showed reduced memory (P < .001) and processing speed (P = .02) and smaller putamen (P < .001), globus pallidus (P = .002), and thalamic volumes (P < .001). Quantitative susceptibility mapping values were increased in patients compared with controls in the putamen (P = .003) and globus pallidus (P = .003). In patients only, thalamus (P < .001) and putamen (P = .04) volumes were related to cognitive performance. After we controlled for volume effects, quantitative susceptibility mapping values in the globus pallidus (P = .03; trend for transverse relaxation rate, P = .10) were still related to cognition. CONCLUSIONS: Quantitative susceptibility mapping was more sensitive compared with the transverse relaxation rate in detecting deep gray matter iron accumulation in the current multiple sclerosis cohort. Atrophy and iron accumulation in deep gray matter both have negative but separable relationships to cognition in multiple sclerosis.

Structural and functional quantitative susceptibility mapping from standard fMRI studies.

Standard functional MRI (fMRI), which includes resting-state or paradigm-driven designs, is widely used in studies of brain function, aging, and disease. These fMRI studies typically use two-dimensional gradient echo-planar imaging, which inherently contains phase data that enables quantitative susceptibility mapping (QSM). This work focuses on the dual value of QSM within fMRI studies, by providing both a localized analysis of functional changes in activated tissue, and iron-sensitive structural maps in deep grey matter (DGM). Using a visual paradigm fMRI study on healthy volunteers at clinical (1.5 T) and high field strength (4.7 T), we perform functional analysis of magnitude and QSM time series, and at the same time harness structural QSM of iron-rich DGM, including globus pallidus, putamen, caudate head, substantia nigra, and red nucleus. The effects of fMRI spatial resolution and time series variation on structural DGM QSM are investigated. Our results indicate that structural DGM QSM is feasible within existing fMRI studies, provided that the voxel dimensions are equal to or less than 3 mm, with higher resolutions preferred. The mean DGM QSM values were about 40 to 220 ppb, while the interquartile ranges of the DGM QSM time series varied from about 3 to 9 ppb, depending on structure and resolution. In contrast, the peak voxel functional QSM (fQSM) changes in activated visual cortex ranged from about -10 to -30 ppb, and functional clusters were consistently smaller on QSM than magnitude fMRI. Mean-level DGM QSM of the time series was successfully extracted in all cases, while fQSM results were more prone to residual background fields and showed less functional change compared with standard magnitude fMRI. Under the conditions prescribed, standard fMRI studies may be used for robust mean-level DGM QSM, enabling study of DGM iron accumulation, in addition to functional analysis. Copyright © 2016 John Wiley & Sons, Ltd.

Chemical composition and antimicrobial activity of the essential oil of the leaves of ocotea caudata (nees) mez (lauraceae) from Colombia / Composición química y actividad antimicrobiana del aceite esencial de las hojas de ocotea caudata (nees) mez(lauraceae) de Colombia

Ocotea is a genus that belong to Lauraceae family, which has about 56 species, distributed in Asia, Africa and mainly in America. The aim of this work was to identify the chemical composition of the essential oil from leaves of Ocotea caudata collected from Colombia. The chemical composition of the oil was determined by gas chromatography-mass spectrometry (GC-MS), being described for the first time. Thirty nine compounds (corresponding to 92.7 percent of the oil) were identified. The major constituents were germacrene D (55.8 percent), bicyclogermacrene (8.0 percent), beta-caryophyllene (4.6 percent) and beta-bourbonene (2.3 percent). Also the antibacterial activity of the oil was evaluated against two Gram (+) and two Gram (-) bacteria showing that the oil exhibited moderated activity against Gram (+) bacteria.

Resumen: Ocotea es un género perteneciente a la familia Lauraceae, que contiene cerca de 56 especies, distribuidas en Asia, Africa yprincipalmente América. El objetivo de este trabajo fue identificar la composición química del aceite esencial de las hojas de Ocoteacaudata colectadas en Colombia. La composición química del aceite fue determinada por cromatografía de gases–espectrometría de masas(GC-MS), siendo descrita por primera vez. Se identificaron treinta y nueve compuestos (correspondientes al 92.7% del aceite). Loscomponentes mayoritarios fueron germacreno D (55.8%), biciclogermacreno (8.0%), β-cariofileno (4.6%) y β-bourboneno (2.3%). Tambiénse evaluó la actividad antibacteriana del aceite frente a dos bacterias Gram (+) y dos Gram (-) encontrándose que el aceite presentómoderada actividad contra las bacterias Gram (+).

Single and multi-component adsorptive removal of bisphenol A and 2,4-dichlorophenol from aqueous solutions with transition metal modified inorganic-organic pillared clay composites: Effect of pH and presence of humic acid.

Pillared clay based composites containing transition metals and a surfactant, namely MAlOr-NaBt (Bt=bentonite; Or=surfactant; M=Ni(2+), Cu(2+)or Co(2+)), were prepared to study selectivity and capacity toward single and multiple-component adsorption of bisphenol A (BPA) and 2,4-diclorophenol (DCP) from water. Tests were also performed to account for the presence of natural organic matter in the form of humic acid (HA). Equilibrium adsorption capacities for single components increased as follows: NaBt

Clasificación de extractos etanólicos de especies de la familia Lauraceae por cromatografía en capa fina bidimensional y análisis estadísticos multivariado CCD-2D/ PCA-cluster / Classification of ethanolic extracts from Lauraceae species by two-dimensional thin layer chromatography and multivariate statistical analyses 2D-TLC/PCA-cluster / Classificação de extratos etanólicos de espécies da família Lauraceae utilizando cromatografia em placa fina bidimensional e estatística multivariada CCD-2D/PCA-cluster

Se caracterizaron los extractos etanólicos de hojas y cortezas de 13 especies de la familia Lauraceae mediante cromatografía en capa fina de dos dimensiones (2D-CCD). Los datos posteriores se analizaron mediante técnicas de análisis estadístico multivariado (cluster y análisis de componentes principales (PCA)). Lo anterior permitió hacer una distinción entre los extractos obtenidos de diferentes partes de la planta (hojas y cortezas). Se observó, además, que la metodología usada es capaz de diferenciar entre extractos obtenidos a partir de especies de Lauraceae y los de otras familias de plantas.

Leaves and barks ethanolic extracts from 13 Lauraceae species were characterized through two-dimensional thin layer chromatography (2D-TLC). The subsequent data was analized through multivariate statistical analysis techniques (cluster analysis and principal components analysis (PCA)). This allowed to do a distinction between extracts obtained from different parts of the plant (leaves and bark). In addition, it was observed that the implemented methodology is able to differentiate between extracts obtained from Lauraceae species and some obtained from other plant families.

Caracterizaram-se os extratos etanólicos de folhas e casca obtidos a partir de espécies da família Lauraceae por cromatografia em camada fina em duas dimensões (2D-CCF). Os dados obtidos foram analisados utilizando técnicas de análise estatística multivariada tipo análise de cluster e análise de componentes principais (PCA). As técnicas estadísticas permitiram fazer uma distinção entre os extratos obtidos a partir de diferentes partes da planta (folhas e casca). Além disso, observou-se que o método utilização é capaz de diferenciar entre os extratos provenientes de espécies de Lauraceae daqueles obtidos a partir de outras famílias de plantas.

Single and multi-component adsorption of salicylic acid, clofibric acid, carbamazepine and caffeine from water onto transition metal modified and partially calcined inorganic-organic pillared clay fixed beds.

Fixed-beds of transition metal (Co(2+), Ni(2+) or Cu(2+)) inorganic-organic pillared clays (IOCs) were prepared to study single- and multi-component non-equilibrium adsorption of a set of pharmaceutical and personal care products (PPCPs: salicylic acid, clofibric acid, carbamazepine and caffeine) from water. Adsorption capacities for single components revealed that the copper(II) IOCs have better affinity toward salicylic and clofibric acid. However, multi-component adsorption tests showed a considerable decrease in adsorption capacity for the acids and an unusual selectivity toward carbamazepine depending on the transition metal. This was attributed to a combination of competition between PPCPs for adsorption sites, adsorbate-adsorbate interactions, and plausible pore blocking caused by carbamazepine. The cobalt(II) IOC bed that was partially calcined to fractionate the surfactant moiety showcased the best selectivity toward caffeine, even during multi-component adsorption. This was due to a combination of a mildly hydrophobic surface and interaction between the PPCP and cobalt(II). In general, the tests suggest that these IOCs may be a potential solution for the removal of PPCPs if employed in a layered-bed configuration, to take care of families of adsorbates in a sequence that would produce sharpened concentration wavefronts.

Componentes volátiles de Eriope crassipes, Hyptis conferta, H. dilatata, H. brachiata, H. suaveolens y H. mutabilis (Lamiaceae) / Volatile compounds of analysis of Eriope crassipes, Hyptis conferta, H. dilatata, H. brachiata, H. suaveolens y H. mutabilis (Lamiaceae)

This work presents the analysis by GC-MS of volatile metabolites of six Lamiaceae from Arauca (Colombia). In stems and leaves of Eriope crassipes were determined as the most abundants: citronellic acid (53,8 percent and 66,2 percent), and methyl citronellate (15,7 percent and 14,5 percent). In the inflorescences of Hyptis conferta were identified: t-cadinol (49,4 percent), and caryophyllene oxide (13,0 percent). From leaves and flowers of Hyptis dilatata were found: delta-3-carene (11,0 percent and 0,5 por ciento), camphor (43,8 percent and 12,2 percent), bornyl acetate (3,2 percent and 25,5 percent), E-caryophyllene (12,8 percent and 22,3 percent), and palustrol (6,0 percent and 10,3 percent). In the leaves of Hyptis brachiata were recognized: E-caryophyllene (8,3 percent), alpha-humulene (19,8 percent), and germacrene D (13,0 percent). The principal compounds in leaves and flowers of Hyptis suaveolens were: alpha-phellandrene (9,4 percent and 0,4 percent), limonene (10,5 percent and 2,5 percent), 1,8-cineole (1,3 percent and 15,2 por ciento), fenchone (10,8 por ciento and tr), E-caryophyllene (26,3 por ciento and 8,0 por ciento), and germacrene D (6,7 por ciento and 14,0 por ciento). In the leaves of Hyptis mutabilis were determined: sabinene (6,6 percent) beta-elemene (6,8 percent), germacrene D (14,9 percent), beta-selinene (8,8 percent), alpha-selinene (9,1 percent), and bicyclogermacrene (6,1 percent), as the most abundants.

Este trabajo presenta el análisis por GC-MS de los metabolitos volátiles de seis Lamiaceae recolectadas en Arauca (Colombia). En tallos y hojas de Eriope crassipes se determinaron como mayoritarios: ácido citronélico (53,8 por ciento y 66,2 por ciento), y citronelato de metilo (15,7 por ciento y 14,5 por ciento). En las inflorescencias de Hyptis conferta se identificaron: t-cadinol (49,4 por ciento), y óxido de cariofileno (13,0 por ciento). En hojas y flores de Hyptis dilatata se encontraron: delta-3-careno (11,0 por ciento y 0,5 por ciento), alcanfor (43,8 por ciento y 12,2 por ciento), acetato de bornilo (3,2 por ciento y 25,5 por ciento), E-cariofileno (12,8 por ciento y 22,3 por ciento), y palustrol (6,0 por ciento y 10,3 por ciento). En las hojas de Hyptis brachiata se reconocieron: E-cariofileno (8,3 por ciento), alfa-humuleno (19,8 por ciento), y germacreno D (13,0 por ciento). Los compuestos principales en hojas y flores de Hyptis suaveolens fueron: alfa-felandreno (9,4 por ciento y 0,4 por ciento), limoneno (10,5 por ciento y 2,5 por ciento), 1,8-cineol (1,3 por ciento y 15,2 por ciento), fenchona (10,8 por ciento y tr), E-cariofileno (26,3 por ciento y 8,0 por ciento), y germacreno D (6,7 por ciento y 14,0 por ciento). En las hojas de Hyptis mutabilis se determinaron: sabineno (6,6 por ciento), beta-elemeno (6,8 por ciento), germacreno D (14,9 por ciento), beta-selineno (8,8 por ciento), alfa-selineno (9,1 por ciento), y biciclogermacreno (6,1 por ciento), como los más abundantes.

The effect of concomitant gradient fields on diffusion tensor imaging.

Concomitant gradient fields are transverse magnetic field components that are necessarily present to satisfy Maxwell's equations when magnetic field gradients are utilized in magnetic resonance imaging. They can have deleterious effects that are more prominent at lower static fields and/or higher gradient strengths. In diffusion tensor imaging schemes that employ large gradients that are not symmetric about a refocusing radiofrequency pulse (unlike Stejskal-Tanner, which is symmetric), concomitant fields may cause phase accrual that could corrupt the diffusion measurement. Theory predicting the error from this dephasing is described and experimentally validated for both Reese twice-refocused and split gradient single spin-echo diffusion gradient schemes. Bias in apparent diffusion coefficient values was experimentally found to worsen with distance from isocenter and with increasing duration of gradient asymmetry in both a phantom and in the brain. The amount of error from concomitant gradient fields depends on many variables, including the diffusion gradient pattern, pulse sequence timing, maximum effective gradient amplitude, static magnetic field strength, voxel size, slice distance from isocenter, and partial Fourier fraction. A prospective correction scheme that can reduce concomitant gradient errors is proposed and verified for diffusion imaging.

Transition metal modified and partially calcined inorganic-organic pillared clays for the adsorption of salicylic acid, clofibric acid, carbamazepine, and caffeine from water.

Pharmaceutical and Personal Care Products (PPCPs) are considered emerging contaminants, and their efficient removal from water is going to be a challenging endeavor. Microporous adsorbent materials, including pillared clays, could offer a potential solution if tailored properly. Although pillared clays have been employed previously for the removal of organics, the effective removal of PPCPs will only be possible if their surface and textural properties are manipulated from the bottom-up. This work presents the use of modified inorganic-organic pillared clays (IOCs) for the adsorption of salicylic acid, clofibric acid, carbamazepine, and caffeine. The IOCs have been modified with Co(2+), Cu(2+), or Ni(2+) to induce complexation-like adsorbate-adsorbent interactions at ambient conditions, in an attempt to provide an efficient and yet reversible driving force in the sub-ppm concentration range. Furthermore, the IOCs were partially calcined to increase effective surface area by an order of magnitude while preserving some hydrophobicity. In general, the Ni(2+) IOCs exhibited the greatest interaction with salicylic and clofibric acids, respectively, while the Co(2+) adsorbents excelled at adsorbing caffeine at low concentrations. All of the metal-modified IOCs showed comparable adsorption capacities for the case of carbamazepine, probably due to the lack of availability of particular functional groups in this adsorbate.

FLAVONOIDES CON ACTIVIDAD ANTIFÚNGICA AISLADOS DE Piper septuplinervium (Miq.) C. DC. (Piperaceae) / ANTIFUNGAL FLAVONOIDS ISOLATED FROM Piper septuplinervium (Miq.) C. DC (Piperaceae) / FLAVONÓIDES COM ATIVIDADE ANTIFÚNGICA ISOLADOS DE Piper septuplinervium (Miq.) C. DC (Piperaceae)

El fraccionamiento bioguiado del extracto etanólico de la parte aérea de Piper septuplinervium (Piperaceae) permitió la obtención de dos substancias de tipo flavonoide, activas contra dos cepas de hongos fitopatógenos (Fusarium oxysporum f. sp. dianthiyBotrytis cinerea). Las estructuras de los compuestos aislados fueron determinadas de acuerdo con el análisis espectroscópico (RMN uni y bidimensional, EMAR). La actividad anti-fúngica fue determinada por ensayo en disco, seguido por bioautografía directa sobre las dos cepas de hongos en prueba.

Guided fractionation of ethanolic extract of aerial part of Piper septuplinervium (Piperaceae) yielded two flavonoid-type active substances against two strains of phytopathogenic fungi (Fusarium oxysporum f. sp. dianthi and Botrytis cinerea). The structures of isolated compounds were determined by spectroscopic analysis (single-and two-dimensional NMR, HRMS). The antifungal activity was determined by disk test, followed by direct bioautography against the two strains of fungi tested.

O fracionamento bio-guiado do extrato etanólico da parte aérea de Piper septuplinervium (Piperaceae) permitiuobter duas substâncias flavonóidesativas contra duas linhagens de fungos patogênicos (Fusarium oxysporum f. sp. Dianthi e Botrytis cinerea). Mediante a análise espectroscópica (RMN mono e bidimensional, RMS) determinaram-se as estruturas desses compostos. A atividade antifúngica foi determinada pelo teste de disco, seguido por bio-autografia direta sobre duas inhagens fúngicas testadas.

Anti-tubercular screening of natural products from Colombian plants: 3-methoxynordomesticine, an inhibitor of MurE ligase of Mycobacterium tuberculosis.

OBJECTIVES: New anti-mycobacterial entities with novel mechanisms of action are clinically needed for treating resistant forms of tuberculosis. The purpose of this study was to evaluate anti-tubercular activity and selectivity of seven recently isolated natural products from Colombian plants. METHODS: MICs were determined using a liquid medium growth inhibition assay for Mycobacterium tuberculosis H(37)Rv and both solid and liquid media growth inhibition assays for Mycobacterium bovis BCG. Escherichia coli growth inhibition and mammalian macrophage cell toxicity were evaluated to establish the degree of selectivity of the natural product against whole cell organisms. Enzymatic inhibition of ATP-dependent MurE ligase from M. tuberculosis was assayed using a colorimetric phosphate detection method. The most active compound, 3-methoxynordomesticine hydrochloride, was further investigated on M. bovis BCG for its inhibition of sigmoidal growth, acid-fast staining and viability counting analysis. RESULTS: Aporphine alkaloids were found to be potent inhibitors of slow-growing mycobacterial pathogens showing favourable selectivity and cytotoxicity. In terms of their endogenous action, the aporphine alkaloids were found inhibitory to M. tuberculosis ATP-dependent MurE ligase at micromolar concentrations. A significantly low MIC was detected for 3-methoxynordomesticine hydrochloride against both M. bovis BCG and M. tuberculosis H(37)Rv. CONCLUSIONS: Considering all the data, 3-methoxynordomesticine hydrochloride was found to be a potent anti-tubercular compound with a favourable specificity profile. The alkaloid showed MurE inhibition and is considered an initial hit for exploring related chemical space.

CONSTITUYENTES QUÍMICOS, ACTIVIDAD INSECTICIDA Y ANTIFÚNGICA DE LOS ACEITES ESENCIALES DE HOJAS DE DOS ESPECIES COLOMBIANAS DEL GÉNERO Ocotea (LAURACEAE) / CHEMICAL CONSTITUENTS, INSECTICIDE AND ANTIFUNGAL ACTIVITIES OF THE ESSENTIAL OILS OF LEAVES OF TWO COLOMBIAN SPECIES OF Ocotea GENUS (LAURACEAE) / CONSTITUENTS QUÍMICOS, ATMDADE ANTIFÚNGICA E INSETICIDA DE ÓLEOS ESSENCIAIS DE FOLHAS DE DUAS ESPECIES COLOMBIANO DO GÉNERO Ocotea (LAURACEAE)

En este estudio se determinó la composición química de los aceites esenciales de hojas de Ocotea longifolia y O. macrophylla obtenidos mediante destilación por arrastre convapor, yse evaluó la actividad antifúngica e insecticida de los aceites esenciales para estimar su uso como posibles plaguicidas. El rendimiento del aceite esencial de O. longifolia fue superior al 0,2%, mientras que el rendimiento del aceite esencial de O. macrophylla fue inferior al 0,1%. El análisis de los aceites por CG/EM permitió la identificación de α-terpinoleno (80,91%) y α-felandreno (4,74%) como componentes principales del aceite O. longifolia, y espatulenol (15,91%), γ-muuroleno (15,4%) y biciclogermacreno (14,58%) como los principales componentes de O. macrophylla. El aceite esencial de O. longifolia mostró actividad fumigante significativa contra Sitophilus zeamais (CL50 280,5 µL/L aire). Adicionalmente se evaluó la actividad antifúngica de los aceites esenciales, encontrándose un bajo efecto inhibidor en el crecimiento de los hongos fitopatógenos Fusarium oxysporum f. sp. dianthi y Botrytis cinerea.

This study determined the chemical composition of the essential oils isolated from leaves of Ocotea longifolia and O. macrophylla by steam distillation and the antifungal and insecticide activities of essential oils as potential pesticides were tested. The yield of essential oil of O. longifolia was more than 0.2%, while the essential oil yield of O. macrophylla was less than 0.1%. GC/MS analysis allowed the identification of α-terpinolene (80.91%) and α-phellandrene (4.74%) as the main constituents of O. longifolia oil, and spathulenol (15.91%), γ-muurolene (15.4%) and bicyclogermacrene (14.58%) as the major constituents of O. macrophylla. The essential oil of O. longifolia showed significant fumigant activity against Sitophilus zeamais (LC50 280.5 µL/L air), and could become an alternative to synthetic pesticides for controlling this pest. The antifungal activity of the essential oils also was evaluated. The essential oils showed low inhibitory effect on the growth of the phytopathogen fungi Fusarium oxysporum f. sp. dianthi and Botrytis cinerea.

Neste estudo nós determinamos a composicào química dos óleos essenciais das folhas de Ocotea longifolia e O. macrophylla obtidas por destilacáo a vapor e avaliaram a atividade antifúngica e inseticida de óleos essenciais para estimar a sua possível utilizacào como pesticidas. O rendimento do óleo essencial de O. longifolia foi superior a 0,2%, enquanto o rendimento doóleo essencial de O. acrophylla foi inferior a 0,1%. A análise dos óleos por CG/EM permitiu a identificacáo de α-terpinolene (80,91%) e α-felandreno (4,74%) como os principais componentes do óleo de O. longifolia, e espatulenol (15,91%), γ-muuroleno (15,4%) e biciclogermacreno (14,58%) como os principais componentes do óleo de O. macrophylla. O óleo essencial de O. longifolia mostraram atividade significativa contra Sitophilus zeamais (CL50 280,5 µL/L ar), e pode se tornar uma alternativa aos inseticidas sintéticos para o controle desta praga. A atividade antifúngica de óleos essenciais também foi avaliada. Os óleos essenciais de O. longifolia e O. macrophylla apresentaram baixo efeito inibitório sobre o crescimento dos fungos Fusarium oxysporum f. sp. dianthi e Botrytis cinerea.

In vivo quantification of hippocampal subfields using 4.7 T fast spin echo imaging.

Several neuropsychiatric disorders involving hippocampal structural changes have been studied extensively using volumetric magnetic resonance imaging (MRI). These studies have mostly measured total hippocampal volume while the present study aimed to delineate and measure hippocampal subfields within the whole hippocampus and subdivisions along its longitudinal axis. Images were acquired at 4.7 T in 11 healthy subjects (5 males and 6 females, aged 23-56 years), using a fast spin echo (FSE) sequence with 0.52 x 0.68 x 1.0 mm(3) native resolution, collecting 90 contiguous coronal slices. Subiculum, cornu ammonis (CA1-3), and dentate gyrus were traced manually within the hippocampal head, body, and tail. We reported volumes for the subfields and demonstrated differences in the distribution within the hippocampus and its parts. The biggest part of the dentate gyrus was located in the hippocampal body, following the hippocampal head and tail. In contrast, the hippocampal head had the largest part of CA1-3, following the hippocampal body and tail. The hippocampal tail had the smallest portion of the subiculum compared to hippocampal head and tail. Subfield volumes were consistent between hemispheres and showed distributions within the longitudinal subdivisions that were consistent with histological data. Direct measurements of subfield distribution along the longitudinal axis of the hippocampus may be more sensitive to detecting disease effects than total volume measures and the differential distribution of subfield volumes may aid in the interpretation of measurements obtained at lower field strength and spatial resolution.

FLAVONOIDES AISLADOS DE LAS INFLORESCENCIAS DE Piper hispidum Kunth (PIPERACEAE) Y DERIVADOS ACETILADOS ISOLATED / FLAVONOIDS FROM INFLORESCENCES OF Piper hispidum Kunth (PIPERACEAE) AND ACETYLATED DERIVATIVES / DERIVATIVES FLAVONOIDES ISOLADOS DAS INFLORESCÊNCIAS DE Piper hispidum Kunth (PIPERACEAE) E DERIVADOS ACETILADOS

A partir del extracto etanílico de las inflorescencias de la especie Piper hispidum Kunth (Piperaceae) fueron aislados tres flavonoides: 5-hidroxi-7-metoxiflavanona, 5-hidroxi-4,7-dimetoxiflavanona y 2,4,6-trimetoxidihidrochalcona. De las flavanonas aisladas fueron obtenidos los derivados acetilados: 5-acetoxi- 7-metoxiflavanona y 5-acetoxi-4,7- dimetoxiflavanona. Las estructuras fueron elucidadas empleando técnicas espectrocópicas y por comparacióncon datos de literatura. Los compuestos naturales y sus derivados fueron sometidos al bioensayo de letalidad frente a Artemia salina. El flavonoide 5-hidroxi-7-metoxiflavanona presenta la mayor actividad tóxica frente a los microcrustáceos CL50 1.8 [1]g/ml.

From the ethanolic extract of the inflorescences of Piper hispidum Kunth (Piperaceae) were isolated three flavonoids 5-hydroxy-7-methoxyflavanone, 5-hydroxy-4,7-dimethoxyflavanone and 2,4,6-trimethoxydihydrochalcone. The acetylated derivatives 5-acetoxy- 7-methoxyflavanone and 5-acetoxy- 4,7- dimethoxyflavanone were synthesized from the isolated pure flavanones. Characterization was mainly achieved by spectroscopic techniques and compared with literature data. Natural compounds and derivatives were subjected to brine shrimp lethality bioassay. The most toxic compound was the flavonoid 5-hydroxy- 7-methoxyflavanone with a LC50 1,8 [1]g/ml.

A partir do extracto etanílico das inflorescancias da especie Piper hispidum Kunth (Piperaceae) foram isolados tras flavonoides: 5-hidroxi-7-metoxiflavanona, 5-hidroxi-4,7-dimetoxiflavanona y 2,4,6-trimetoxidihidrochalcona. Das flavanonas isoladas foram sintetizados os derivados acetilados 5-acetoxi-7-metoxiflavanona y 5-acetoxi-4,7-dimetoxiflavanona. As estruturas foram elucidadas empregando técnicas espectrocópicas e por comparasau com dados da literatura. Os compostos naturais e seus derivados foram submetidos a bioensaáos de letalidade frente a Artemia salina. O flavonoide 5-hidroxi-7-metoxiflavanona presenta uma major atividad toxica frente aos microcrustaceos CL50 1,8 [1]g/ml.

Basal ganglia activation in Parkinson's disease.

The objective of this study was to compare basal ganglia activation in patients with Parkinson's disease to that of healthy controls, using functional MRI (fMRI). Six mildly-affected patients, off antiparkinsonian medications for at least 12h, and seven age-matched controls performed a unilateral motor switching task during fMRI data acquisition. Clear differences in basal ganglia activation were seen, with control subjects showing greater activation during both the left and right movement sessions. We observed activation of right sided basal ganglia structures in both groups, particularly with right sided movements, with caudate activation noted most frequently. This observation is consistent with right caudate involvement in the learning of new tasks and in association with externally paced movements.

Quantitative evaluation of nonrepetitive phase-encoding orders for first-pass, 3D contrast-enhanced MR angiography.

In this work, a detailed quantitative comparison was made of many alternative phase-encoding strategies for first-pass 3D MR angiography where each phase encode is only sampled once during the transient passage of contrast agent. A series of standard sequential and centric phase-encoding orders including elliptical centric were tested, as well as a new order called elliptical sequential. The characteristics of the different phase-encoding orders were tested using a computer simulation followed by experimental verification using a variable flip angle scheme. The characteristics to be considered included: arterial intensity, arterial-to-venous contrast, degree of artifact, and the blurring of the point-spread function. By making use of a wide range of start times and a rapidly varying contrast curve, the quantitative results clearly indicate the widely varying merits of each phase-encoding order. In general, when an optimal start time is used techniques that sample the low k-space views most compactly will produce the best results; however, the same methods are more problematic when the bolus arrival time deviates substantially from that expected.

On the cause of increased aliasing in the slice-select direction in 3D contrast-enhanced magnetic resonance angiography.

The combination of short repetition times and large flip angles typically used in 3D contrast-enhanced magnetic resonance angiography (3D CE MRA) can significantly alter the expected shape of the slab profile for unenhanced tissues, which can cause increased aliasing in the slice select direction. In this work, this increased slice select aliasing is demonstrated and explained from both theoretical and experimental points of view. The effect is due to the Ernst angle of unenhanced background tissue occurring on the falling edges of the flip angle profile that has been set for the significantly reduced T(1) of contrast-enhanced blood. The deleterious aliasing effects are magnified substantially when the chosen volume is placed close to surface coil reception with the slice select direction perpendicular to the coil axis. Magn Reson Med 44:336-338, 2000.