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Objetivos: Determinar la confiabilidad interobservador de la evaluación de la fuerza muscular de rotadores de hombro mediante el dinamómetro handgrip (HG). Materiales y métodos: Se incluyeron 21 participantes voluntarios sanos. Se analizó la confiabilidad entre la primera y segunda medición realizada por 2 diferentes operadores para la rotación externa e interna, tanto del miembro dominante como del no dominante. Se utilizó el Coeficientede Correlación Intraclase (CCI) con sus respectivos intervalos de confianza al 95%. Para determinar el umbral de cambio real en la fuerza de HG cuando diferentes valuadoresregistran las mediciones, se calculó el mínimo cambio detectable (MCD) Resultados: Se observó una excelente confiabilidad entre evaluador para la rotación externa dominante y no dominante (CCI= 0.80 [IC95% 0.58 - 0.92] y CCI 0.80 [IC95%= 0.56 - 0.91], respectivamente). La confiabilidad interevaluador para la rotación interna dominante resultó regular(CCI: 0.56 [IC95% 0.18 - 0.80] y para la no dominante buena (CCI:0.61 [IC95% 0.25 - 0.82]). Conclusión: El estudio mostró que la confiabilidad interobservador de la herramienta HG para medir fuerza de hombro es excelente para los rotadores externos y de regular a buena para los rotadores internos.

El presente artículo expone cómo es que los pueblos originarios han fortalecido su identidad a través de la asamblea comunitaria, medio de justicia tradicional para solucionar los conflictos de índole local básico y para ejercer la toma de decisiones en la comunidad indígena, y que ha sido clave en el reconocimiento por primera vez en la historia de Guerrero de un pueblo con gobierno comunitario en Ayutla. Aplicando la investigación documental, la observación presencial de algunas asambleas comunales y analizando desde la antropología social los usos y costumbres de los pueblos originarios, se alcanzó a vislumbrar el desarrollo de medios de solución a conflictos tratados en las asambleas y cómo es que previo a estas se da un diálogo ciudadano ceremonial. Esta efectiva forma de organización está construyendo un sistema nuevo desde lo local. Se trata de una de las formas de organización campesina que tiene posibilidades de enraizarse y consolidarse como una fuerza de resistencia a la añeja política de destrucción del mundo indígena.

El pastoreo es una perturbación importante en los ecosistemas de pastizales, ya que altera su estructura y su funcionamiento. Las micorrizas arbusculares son interacciones cosmopolitas de estos ecosistemas, y se destacan por su incidencia elevada en las gramíneas. Las micorrizas muestran respuestas diversas y contradictorias al pastoreo (ser beneficiadas, perjudicadas o no ser afectadas). Una posible hipótesis es que cada componente del pastoreo (defoliación selectiva, deyecciones y pisoteo) diferiría en su importancia relativa al afectar la micorrización. El objetivo del presente trabajo fue evaluar el efecto del pisoteo, la selectividad y la deposición de orina sobre las micorrizas de Paspalum dilatatum, una de las principales gramíneas nativas de los pastizales del Río de la Plata. En un experimento manipulativo en el que se simularon los distintos componentes del pastoreo se evaluó el efecto de cada componente de forma aislada y en interacción sobre la colonización micorrícica total, así como de las diferentes estructuras fúngicas (arbúsculos, ovillos y vesículas). La colonización micorrícica total y por arbúsculos no fueron afectadas por ninguno de los componentes del pastoreo, mientras que sí se observaron efectos sobre las demás estructuras fúngicas. La colonización por ovillos (una de las estructuras que participan en el intercambio con el hospedante) fue afectada de forma positiva por la selectividad y negativa por el agregado de nitrógeno (simulando la deposición de orina); estas estructuras también fueron afectadas por las interacciones selectividad x pisoteo y pisoteo x agregado de N. El pisoteo afectó negativamente la presencia de vesículas, lo que podría deberse, en parte, al daño mecánico que esta perturbación causa tanto sobre las raíces como sobre el micelio extra-radical. El estudio de los componentes del pastoreo de manera aislada mostró que cada uno ejerce efectos diferentes sobre las micorrizas, y su importancia relativa podría afectar el resultado global del pastoreo sobre esta interacción. Grazing by large herbivores represents an important disturbance in natural grasslands, affecting its structure and function. Arbuscular mycorrhizas (AM) are cosmopolitan interactions in these ecosystems, particularly in grasses, main constituent of this ecosystem. Mycorrhizas show contradictory responses to grazing (AM colonization has been positively, negatively and not affected by grazing). We hypothesized that each grazing component (selective defoliation, trampling and urine deposition) would differentially affect mycorrhizal colonization, and this could explain the high variability in AM responses. Our objective was to assess the effect of trampling, selective defoliation and nitrogen (N) addition on AM colonization of one of the most important grasses in Río de la Plata grasslands: Paspalum dilatatum. Grazing components were simulated in a manipulative experiment where we evaluated their individual and combined effects on total AM colonization and the occurrence of different fungal structures (arbuscules, coils and vesicles). No grazing component affected total AM colonization and arbuscules, while other fungi structures were affected by different treatments. Coil colonization (one of the nutrient interchange structures between the symbionts) was positively affected by selective defoliation and it was negatively affected by N addition; these structures were also affected by the combined effect between selectivity x trampling and by trampling x N addition. Vesicle colonization was negatively affected by trampling, maybe because of mechanical damage to roots and to extraradical mycelium caused by this disturb. The study of the individual grazing components showed that each one caused different effects on mycorrhizal interaction and their relative influence could affect the overall grazing effect on this interaction.

En Uruguay el campo natural (CN) es el ecosistema dominante, relevante para la producción ganadera extensiva. Está constituido principalmente por gramíneas, especies que muestran alta micorrización. Los contenidos de fósforo (P) del CN son bajos, por lo que se llevan a cabo prácticas de fertilización fosfatada. El impacto de esta práctica sobre la comunidad vegetal difiere entre especies. El objetivo del trabajo fue estudiar el efecto del P sobre la colonización micorrícica en dos gramíneas nativas con respuestas diferenciales al agregado de P: Paspalum dilatatum y Coelorhachis selloana. Se planteó que las dos especies vegetales presentarían diferente micorrización en respuesta al P, lo que podría explicar en parte sus diferentes persistencias en suelos fertilizados. Se utilizó un experimento de larga duración instalado en INIA Palo a Pique, con tres tratamientos: CN sin fertilización y con fertilización fosfatada media y alta. Se evaluó la micorrización (total y por estructuras fúngicas) en P. dilatatum (mantuvo su frecuencia en parcelas fertilizadas con P) y en C. selloana (redujo su frecuencia). La fertilización fosfatada afectó negativamente la micorrización de ambas gramíneas y dicho efecto dependió de la estación del año. Dado que estos resultados fueron independientes de la respuesta de la especie en la comunidad vegetal, existirían otros factores involucrados en determinar el desempeño de estas gramíneas en situaciones de incremento de P. En ambientes con mayor contenido de P habría un control fitocéntrico que limitaría la micorrización considerando el costo energético que esta interacción tiene para las plantas. Natural grasslands (NG) are the major Uruguayan ecosystem and are relevant for extensive livestock production. They consist mainly of grasses with high mycorrhizal colonization. NG soils have low phosphorus (P) content, so fertilization practices are carried out. The impact of this practice on the vegetal community differs between species. The aim of this work was to study the effect of P on mycorrhizal colonization in two native grasses with differential responses to the addition of P: Paspalum dilatatum and Coelorhachis selloana. It was suggested that the two species would present different mycorrhizal response to P, which could partly explain its persistence in fertilized soil. We used a long-term experiment from INIA Palo a Pique, with three treatments: NG without fertilization, and with high and medium levels of P fertilization. We evaluated mycorrhizal colonization (total and by fungal structures) in P. dilatatum (which maintained its frequency in plots fertilized with P) and in C. selloana (which reduced its frequency). P fertilization negatively affected mycorrhizal interaction with both grasses, and this effect was dependent on the season. Since these results were independent of the response of the species in the plant community, we postulated that there would be other factors involved in determining the performance of these grasses in situations of increasing P. In environments with higher content of P there would be a phytocentric control that would limit the mycorrhization considering the energetic cost that this interaction has for plants.

The secretion of the paracloacal glands of the American crocodile (Crocodylus acutus) contains over 80 lipophilic compounds, including saturated and unsaturated long-chain alcohols along with their formic, acetic, and butyric acid esters, and several isoprenoids. Most of these compounds were identified on the basis of mass spectra, obtained by GC-MS. In addition, identification of the major components was supported by infrared spectra obtained by GC-FTIR. Major differences are indicated in the composition of the paracloacal gland secretion of C. acutus and that of another crocodylid, the African dwarf crocodile (Osteolaemus tetraspis).

The synthesis of three analogues of the single most abundant component of a ladybird beetle (Epilachna borealis) defensive secretion, the trimeric 42-membered polyazamacrolide PAML 681, is described. Construction of the nonnatural macrocyclic trimers began with the preparation of the corresponding monomeric segments, followed by their oligomerization and a final macrolactonization step of the activated linear trimeric hydroxy acid. The relative rates of the O-to-N acyl migrations that are characteristic of PAML 681 itself, as well as of the synthetic analogues, were investigated. These studies showed that changes in the substitution pattern adjacent to the nucleophilic nitrogen atom, along with changes in the size of the oxaazacyclic intermediates, have substantial effects on the polyazamacrolide rearrangement rates.

The collisionally-induced dissociation mass spectra of a variety of organic sulfate ester anions are described and mechanistically rationalized. A cyclic syn-elimination pathway, analogous to that of the Cope elimination, is postulated for the commonly observed formation of bisulfate anion (HSO4−, m/z 97). Deuterium labeling experiments confirm that the proton transferred to oxygen during bisulfate elimination normally originates from the C-2 position, although examination of the spectra of polyfunctional steroids reveals that the proton abstracted may originate from more distant sites as well. Adamantyl, phenyl, and vinyl sulfate anions, which do not readily lend themselves to a cyclic syn-elimination, do not give rise to an m/z 97 ion. Instead, these sulfates undergo both heterolytic and homolytic S–O bond cleavages to yield an m/z M − 80 anion, resulting from loss of neutral SO3, as well as an ion at m/z 80, corresponding to SO3−˙, respectively. Sulfates that can give rise to a resonance stabilized radical by homolytic C–O bond fission, as exemplified by benzyl and linalyl sulfates, can be recognized by the formation of an m/z 96 (SO4−˙) ion.

A total synthesis of (-)-strychnine in 15 steps from 1,3-cyclohexanedione in 0.15% overall yield is described. The sequence followed in the assembling of rings is: E-->AE [2-(2-nitrophenyl)-1,3-cyclohexanedione]-->ACE (3a-aryloctahydroindol-4-one)-->ACDE (arylazatricyclic core)-->ABCDE (strychnan skeleton)-->ABCDEF (Wieland-Gumlich aldehyde)-->ABCDEFG (strychnine). The key steps of the synthesis are the enantioselective construction of the 3a-(2-nitrophenyl)-octahydroindol-4-one ring system and the closure of the piperidine ring by a reductive Heck cyclization to generate the pivotal intermediate (-)-14. In contrast, a Lewis acid promoted a-alkoxypropargylic silane-enone cyclization did not lead to synthetically useful azatricyclic ACDE intermediates. The introduction of C-17 and the closure of the indoline ring by reductive amination of the alpha-(2-nitrophenyl) ketone moiety complete the strychnan skeleton from which, via the Wieland-Gumlich aldehyde, the synthesis of (-)-strychnine is achieved.

A general strategy for the synthesis of pentacyclic Strychnos alkaloids with the curan skeleton has been developed. It utilizes 3a-(2-nitrophenyl)hexahydroindol-4-one (23), which was prepared from 2-allyl-2-(2-nitrophenyl)-1,3-cyclohexanedione (15), as the common, pivotal intermediate. Three different procedures have been employed for the closure of the bridged piperidine D ring from 23: (i) an intramolecular Michael-type conjugate addition; (ii) a Ni(COD)2-promoted biscyclization that assembles B and D rings in a single synthetic step, and (iii) an intramolecular cyclization of an enone−propargylic silane system. When necessary, depending on the procedure used, introduction of the oxidized one-carbon substituent at C-16, closure of the indole ring, and/or adjustment of the functionality of the C-20 two-carbon chain constitute the last stages of the synthetic route to the title alkaloids. The procedure involving the cyclization of a propargylic silane has been successfully extended to the enantiospecific...

Alkylation of cis -3a-( o -nitrophenyl)hexahydroindol-4-one 1 with 1-iodo-4-(trimethylsilyl)-2-butyne followed by BF 3 ·Et 2 O-promoted cyclization of the resulting propargylic silane 2 afforded the tricyclic vinylidene ketone 3 , which was further converted to the Strychnos alkaloids tubifolidine, 19,20-dihydroakuammicine, and akuammicine.

Alkylation of cis -3a-( o -nitrophenyl)hexahydroindol-4-one 1 with 1-iodo-4-(trimethylsilyl)-2-butyne followed by BF 3 ·Et 2 O-promoted cyclization of the resulting propargylic silane 2 afforded the tricyclic vinylidene ketone 3 , which was further converted to the Strychnos alkaloids tubifolidine, 19,20-dihydroakuammicine, and akuammicine.

Fifteen steps suffice for an enantioselective total synthesis of (-)-strychnine (1) from 1,3-cyclohexanedione. The key steps are the easy generation of the enantiopure intermediate 2, the closure of the piperidine ring by a reductive Heck reaction, and the elaboration of the indoline nucleus in an advanced synthetic stage. TBDMS=tert-butyldimethylsilyl.

Fifteen steps suffice for an enantioselective total synthesis of (-)-strychnine (1) from 1,3-cyclohexanedione. The key steps are the easy generation of the enantiopure intermediate 2, the closure of the piperidine ring by a reductive Heck reaction, and the elaboration of the indoline nucleus in an advanced synthetic stage. TBDMS=tert-butyldimethylsilyl.

Akuammiline alkaloids are a family of monoterpene indole alkaloids of renewed medicinal interest. These bases act as ligands for a heterogeneous group of molecular targets and, consequently, display a wide variety of pharmacological activities. For example, pseudoakuammigine (2) exhibits opioid activity in vivo, echitamine (4) has been reported to have promising cytotoxic activity, and corymine (121) behaves as an antagonist of the glycine receptor. Oddly enough, these alkaloids have not raised enough interest in the organic synthesis community, remaining inaccessible; even the entry to their pentacyclic framework continues elusive. Recently, several akuammiline bases have been isolated and identified including bisindole alkaloids, such as vingramine (103) or rausutrine (110), which incorporate akuammiline-type subunits. This review covers the advances in the chemistry and pharmacology of akuammiline alkaloids reported within the last ten years.

The secretion of the paracloacal glands of the American crocodile (Crocodylus acutus) contains over 80 lipophilic compounds, including saturated and unsaturated long-chain alcohols along with their formic, acetic, and butyric acid esters, and several isoprenoids. Most of these compounds were identified on the basis of mass spectra, obtained by GC-MS. In addition, identification of the major components was supported by infrared spectra obtained by GC-FTIR. Major differences are indicated in the composition of the paracloacal gland secretion of C. acutus and that of another crocodylid, the African dwarf crocodile (Osteolaemus tetraspis).

Due to differences in the result of the Direct Microscopic Test (DMT) and culture for fungi, the technique of neutral red supravital coloration has been put to practice and in this manner, evaluate the mycological cure. Patients and Methods: In order to achieve this purpose, 30 patients with presumptive diagnosis of superficial mycosis submitted from the Capital City of Córdoba and surrounding districts were evaluated. Once the laboratory diagnosis was confirmed, clinical cases with the following requirements were selected: patients with skin mycosis in different zones; had not received previous treatment for mycosis. Five patients who fulfilled both previous requirements, wanted to receive complete antifungal treatment and accepted to undergo both, clinical and laboratory periodical follow _ups, were enrolled. The material obtained from the selected patients was assessed with the habitual technique of microscopic observation (KOH and heat). At the same time fungal cultures were performed, the coloration of neutral red was utilized in each of the selected patients. The results obtained were very promising. This fact allowed us to put this technique into practice as a routine. Besides, its low price constitutes an advantage that can be applied to any laboratory that makes mycologic diagnosis