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Amine and nicotinamide groups grafted on ordered mesoporous silica (OMS) were investigated as stabilizers for RhNPs used as catalysts in the hydrogenation of several substrates, including carbonyl and aryl groups. Supported RhNPs on functionalized OMS were prepared by controlled decomposition of an organometallic precursor of rhodium under dihydrogen pressure. The resulting materials were characterized thoroughly by spectroscopic and physical techniques (FTIR, TGA, BET, SEM, TEM, EDX, XPS) to confirm the formation of spherical rhodium nanoparticles with a narrow size distribution supported on the silica surface. The use of nicotinamide functionalized OMS as a support afforded small RhNPs (2.3 ± 0.3 nm), and their size and shape were maintained after the catalyzed acetophenone hydrogenation. In contrast, amine-functionalized OMS formed RhNP aggregates after the catalytic reaction. The supported RhNPs could selectively reduce alkenyl, carbonyl, aryl and heteroaryl groups and were active in the reductive amination of phenol and morpholine, using a low concentration of the precious metal (0.07–0.18 mol%).

BACKGROUND: Riociguat and phosphodiesterase-5 inhibitors (PDE5i), approved for the treatment of pulmonary arterial hypertension (PAH), act on the same pathway via different mechanisms. Riociguat might be an alternative option for patients with PAH who do not respond sufficiently to treatment with PDE5i, but comparisons of the potential benefits of riociguat and PDE5i in these patients are needed. The aim of this trial was to assess the effects of switching to riociguat from PDE5i therapy versus continued PDE5i therapy in patients with PAH at intermediate risk of 1-year mortality.METHODS: Riociguat rEplacing PDE5i therapy evaLuated Against Continued PDE5i thErapy (REPLACE) was an open-label, randomised controlled trial in 81 hospital-based pulmonary hypertension centres in 22 countries. The study enrolled patients aged 18-75 years with symptomatic PAH at intermediate risk of 1-year mortality (based on the European Society for Cardiology-European Respiratory Society guideline thresholds for WHO functional class and 6-min walk distance [6MWD]) who were receiving treatment with a PDE5i with or without an endothelin receptor antagonist for at least 6 weeks before randomisation. Patients were excluded if they had been previously treated with riociguat, had used prostacyclin analogues or prostacyclin receptor agonists within 30 days before randomisation, had clinically significant restrictive or obstructive parenchymal lung disease, or had left heart disease. Patients were randomly assigned (1:1) to remain on PDE5i treatment (oral sildenafil [≥60 mg per day] or oral tadalafil [20-40 mg per day]; the PDE5i group) or to switch to oral riociguat (up to 2·5 mg three times per day; the riociguat group), using an interactive voice and web response system, stratified by cause of PAH. The primary endpoint was clinical improvement by week 24, defined as an absence of clinical worsening and prespecified improvements in at least two of three variables (6MWD, WHO functional class, and N-terminal prohormone of brain natriuretic peptide), analysed using last observation carried forward in all randomly assigned patients with observed values at baseline and week 24 who received at least one dose of study medication (the full analysis set). Secondary endpoints included clinical worsening events. The trial has been completed and is registered with ClinicalTrials.gov, NCT02891850.FINDINGS: Between Jan 11, 2017, and July 31, 2019, 293 patients were screened, of which 226 patients were randomly assigned to the riociguat group (n=111) or to the PDE5i group (n=115). 211 patients completed the study and 14 patients discontinued (seven in each group). One patient assigned to the PDE5i group did not receive treatment, so 225 patients were included in the safety analysis, and one further patient in the PDE5i group had missing components of the composite primary endpoint at baseline, so 224 patients were included in the full analysis set. The primary endpoint was met by 45 (41%) of 111 patients in the riociguat group and 23 (20%) of 113 patients in the PDE5i group; odds ratio [OR] 2·78 (95% CI 1·53-5·06; p=0·0007). Clinical worsening events occurred in one (1%) of 111 patients in the riociguat group (hospitalisation due to worsening PAH) and 10 (9%) of 114 patients in the PDE5i group (hospitalisation due to worsening PAH [n=9]; disease progression [n=1]; OR 0·10 [0·01-0·73]; p=0·0047). The most frequently occurring adverse events were hypotension (15 [14%]), headache (14 [13%]), and dyspepsia (10 [9%]) in the riociguat group, and headache (eight [7%]), cough (seven [6%]), and upper respiratory tract infection (seven [6%]) in the PDE5i group. Serious adverse events were reported in eight (7%) of 111 patients in the riociguat group and 19 (17%) of 114 patients in the PDE5i group. During the study, four patients died in the PDE5i group, one of them during the safety follow-up period.INTERPRETATION: Switching to riociguat from PDE5i treatment, both of which act via the nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate pathway, could be a strategic option for treatment escalation in patients with PAH at intermediate risk of 1-year mortality.FUNDING: Bayer AG, Merck Sharp & Dohme.

Amine and nicotinamide groups grafted on ordered mesoporous silica (OMS) were investigated as stabilizers for RhNPs used as catalysts in the hydrogenation of several substrates, including carbonyl and aryl groups. Supported RhNPs on functionalized OMS were prepared by controlled decomposition of an organometallic precursor of rhodium under dihydrogen pressure. The resulting materials were characterized thoroughly by spectroscopic and physical techniques (FTIR, TGA, BET, SEM, TEM, EDX, XPS) to confirm the formation of spherical rhodium nanoparticles with a narrow size distribution supported on the silica surface. The use of nicotinamide functionalized OMS as a support afforded small RhNPs (2.3 ± 0.3 nm), and their size and shape were maintained after the catalyzed acetophenone hydrogenation. In contrast, amine-functionalized OMS formed RhNP aggregates after the catalytic reaction. The supported RhNPs could selectively reduce alkenyl, carbonyl, aryl and heteroaryl groups and were active in the reductive amination of phenol and morpholine, using a low concentration of the precious metal (0.07-0.18 mol%).

The Mauritia flexuosa L.f. palm is known as the "tree of life" given its importance as fundamental food and construction resources for humans. The species is broadly distributed in wet habitats of Amazonia and dry habitats of the Amazon and Orinoco river basins and in the Cerrado savanna. We collected 179 individuals from eight different localities throughout these habitats and used microsatellites to characterize their population structure and patterns of gene flow. Overall, we found high genetic variation, except in one savanna locality. Gene flow between populations is largely congruent with river basins and the direction of water flow within and among them, suggesting their importance for seed dispersal. Further, rivers have had a higher frequency of human settlements than forested sites, contributing to population diversity and structure through increased human use and consumption of M. flexuosa along rivers. Gene flow patterns revealed that migrants are sourced primarily from within the same river basin, such as those from Madeira and Tapajos basins. Our work suggests that rivers and their inhabitants are a critical element of the landscape in Amazonia and have impacted the dispersal and subsequent distribution of tropical palm species, as shown by the patterns of genetic variation in M. flexuosa.

Background: Oral treprostinil (TRE) decreased the risk of adjudicated clinical worsening (CW) compared to placebo (PBO) in FREEDOM-EV (HR 0.74; 95% CI 0.56,0.97; p=0.0391). This prespecified analysis hypothesized that changes in NT-proBNP, World Health Organization Functional Class (FC), Borg dyspnea score (BDS), and 6-minute walk distance (6MWD) would be dose-dependent. Methods: Participants with pulmonary arterial hypertension (PAH) taking one PAH medication were randomized to TRE or PBO and titrated to 12 mg thrice daily (TID). Results are compared for TRE Results: Baseline characteristics were similar. More than half (54%) assigned to TRE reached ≥3 mg TID at W24; median dose was 3.6 mg TID. The ≥3 mg TID group had greater clinical response compared to PBO and Conclusions: Higher TRE dose facilitated greater clinical improvements at W24 in this a priori analysis. Although 6MWD effect with ≥3 mg TID was modest, it was coupled with a significant reduction in BDS. AEs did not appear dose dependent. A dose ≥3 mg TID may be a reasonable initial target in clinical practice.

La presente investigación pretende analizar a partir del caso del laurel silvestre del Parque Nacional el Chico (PNECh), la relación que existe entre esta especie no maderable y el turismo (actividad que ha sido promovida en esta área protegida desde hace más de tres décadas), a partir del análisis de su abundancia y usos en las comunidades locales. Se realizó un análisis de la abundancia de las poblaciones de la especie en zonas con turismo y sin turismo dentro del área protegida. Se utilizaron métodos etnográficos como entrevistas abiertas y semi-estructuradas para conocer los usos de la planta en las localidades aledañas a la zona y caracterizar la red de comercialización. Se documentaron, a partir de la observación participante, los usos del laurel en las festividades de Semana Santa. Se encontró que las poblaciones de laurel dentro de este espacio protegido son más abundantes en sitios sin turismo. La actividad turística no está relacionada directamente con los usos de la planta. Los usos religiosos fueron menos frecuentes, a diferencia de los casos que se documentaron en el Estado de México y otros sitios de Hidalgo, en donde el uso religioso tiene valor social y ceremonial importante. En la cadena de comercialización de la planta participan diferentes actores que la venden en mercados locales de la capital del estado, sin embargo, es en la Ciudad de México en donde se da una venta considerable. Como conclusión, la actividad turística del Parque Nacional no influye directamente en la abundancia de laurel, así como tampoco en la comercialización del mismo, en esta área protegida sus usos principales son como condimento y es ofrecido a los turistas a través de la gastronomía, pero en cantidades mínimas. En regiones aledañas al Parque sus usos están mayormente relacionados con aspectos religiosos. La comercialización se da principalmente fuera de la región.

Background: In pulmonary arterial hypertension (PAH), acute vasodilator response testing (AVT) is considered important to identify adult patients with favorable prognosis using calcium-chan...

El manejo de vida silvestre incluye todas aquellas acciones que se realizan para obtener beneficios ecológicos, socioculturales o económicos provenientes de la vida silvestre. En la actualidad, se plantea el manejo bajo un enfoque de sustentabilidad, por lo que resulta urgente reconciliar dos acciones que se consideraban en el pasado como incompatibles, la obtención de una rentabilidad económica de las actividades humanas y la preservación a largo plazo de la biodiversidad. Bajo la directriz de la sustentabilidad deberán de conjugarse a través de un manejo que logre según las necesidades mantener, aumentar, estabilizar o disminuir una población de vida silvestre de manera que estas acciones impacten en la conservación, control, reproducción o aprovechamiento sustentable fuera o dentro de su hábitat natural. El manejo adecuado de vida silvestre solo se consigue con la participación de los diferentes actores involucrados, quienes deberán adoptar una evaluación técnica-científica, tomando en cuenta el bienestar animal, aplicar conocimientos básicos y tradicionales y acatar la legislación vigente.

This paper scrutinises claims made about the promise and efficacy of ecosystems-based adaptation (EBA), through an exploration of EBA-relevant interventions in two fieldsites in Mexico. Our data starts to fill important gaps in current global debates about EBA. We find evidence of the important contribution of interventions relevant to EBA objectives at a small scale and under very specific conditions. However, the viability of similar interventions is substantially reduced, and arguably rendered null, as an incentive for conservation in a more populous fieldsites. Furthermore, evidence suggests that other adaptation options risked being overlooked if the context were viewed solely through the lens of EBA. We conclude that EBA needs to: a) engage with and address the trade-offs which characterised earlier attempts to integrate conservation and development, and; b) acknowledge the implications for its objectives of a globally predominant, neoliberal political economy.

Ceratozamia fuscoviridis, or teosintle in nahuatl, is a recently rediscovered endangered cycad species previously known from only one population (Molango) in Sierra Madre Oriental of the State of Hidalgo, Mexico. Recent botanical explorations have found new but scattered populations, increasing its known geographical range. Ecological studies were conducted on six of the 29 populations found. Parameters such as size, density, population structure, and static life table are presented. This is the first study of its kind conducted to prompt the Mexican authorities to establish natural protected areas for this species and the associated biodiversity, because deforestation is rapidly diminishing the populations. The population structure in general showed a Deevey-III curve, while two populations showed Deevey-I curves. A 400 m2 area had a population size from 143 to 378 individuals. Population density varied from 0.358 individuals/m2 to 0.945 individuals/m2. Population structure was statistically different among populations. The large amount of seedlings in all sites was distinctive and indicated the specie's reproductive success even in small forest fragments. This research provides the most complete information available to date regarding populations of C. fuscoviridis. Future protected areas established in the better conserved populations could enable the populations' rapid recovery. This study shows that C. fuscoviridis is not as restricted in area as previously believed. We suggest the IUCN Red listing category of the species be amended from Critically Endangered (CR) to Endangered (EN) in view of newly discovered populations, high population size, and successful recruitment.

Blood culture contamination can occur from extraction to processing; its rate should not exceed 3%.To evaluate the impact of a training programme on the rate of contaminated blood cultures after the implementation of sample extraction recommendations based on the best evidence.Prospective before-after study in a polyvalent intensive care unit with 18 beds. Two phases were established (January-June 2012, October 2012-October 2015) with a training period between them. Main recommendations: sterile technique, surgical mask, double skin disinfection (70° alcohol and 2% alcoholic chlorhexidine), 70° alcohol disinfection of culture flasks and injection of samples without changing needles. Including all blood cultures of patients with extraction request.demographic, severity, pathology, reason for admission, stay and results of blood cultures (negative, positive and contaminated). Basic descriptive statistics: mean (standard deviation), median (interquartile range) and percentage (95% confidence interval). Calculated contamination rates per 100 blood cultures extracted. Bivariate analysis between periods.Four hundred and eight patients were included. Eight hundred and forty-one blood cultures were taken, 33 of which were contaminated. In the demographic variables, severity, diagnosis and stay of patients with contaminated samples, no differences were observed from those with uncontaminated samples. Pre-training vs post-training contamination rates: 14 vs 5.6 per 100 blood cultures extracted (P=.00003).An evidence-based training programme reduced the contamination of samples. It is necessary to continue working on the planning of activities and care to improve the detection of pollutants and prevent contamination of samples.

The Mauritia flexuosa L.f. palm is known as the “tree of life” given its importance as fundamental food and construction resources for humans. The species is broadly distributed in wet habitats of Amazonia and dry habitats of the Amazon and Orinoco river basins and in the Cerrado savanna. We collected 179 individuals from eight different localities throughout these habitats and used microsatellites to characterize their population structure and patterns of gene flow. Overall, we found high genetic variation, except in one savanna locality. Gene flow between populations is largely congruent with river basins and the direction of water flow within and among them, suggesting their importance for seed dispersal. Further, rivers have had a higher frequency of human settlements than forested sites, contributing to population diversity and structure through increased human use and consumption of M. flexuosa along rivers. Gene flow patterns revealed that migrants are sourced primarily from within the same river basin, such as those from Madeira and Tapajós basins. Our work suggests that rivers and their inhabitants are a critical element of the landscape in Amazonia and have impacted the dispersal and subsequent distribution of tropical palm species, as shown by the patterns of genetic variation in M. flexuosa.

Documenting how socio-ecosystem conservation knowledge and practice arise and are modified are issues of ethnobiological interest. In the Barranca de Metztitlán Biosphere Reserve (RBBM), plant nurseries, some of which were created as Environmental Management Units (UMAs), have been established to grow and conserve cacti. This paper describes these nurseries, their role in cactus conservation, and the benefits and limitations for the people managing them. The nurseries have helped decrease illegal traffic in cacti and have enabled ex situ conservation of 22 cacti species. Cactus management has changed from extraction to cultivation, as a result of the knowledge and actions of multiple actors. The main limitation is marketing, a recurring problem for non-timber forest products (NTFP). Greater coordination among stakeholders is recommended, such as involvement by non-governmental organizations to improve their probability of success, as well as learning from the experience of other cactus UMAs. Improving the market for cacti is an issue that needs an immediate solution; otherwise conservation efforts could relapse.

Seed dynamics are an important part of the life history of plants and may have strong implications on abundance and spatial distribution of populations. In this study, we explored how seed dynamics (removal, predation, germination) interact with micro-environmental conditions to affect the spatial structure of populations of Brahea aculeata (Arecaceae) in a tropical dry forest. B. aculeata is distributed throughout arroyo basins and attains its highest densities near to arroyos/rivers. We hypothesized that: (i) seed removal, predation and germination vary across topographic positions resulting in greater palm abundances adjacent to arroyos and (ii) seed removers/predators respond to both a seed density-dependent effect and a microclimate effect. To test this, in six arroyos basins, seeds were sown across three topographic positions (stream, mid and top of basins) with two seed abundances (1 and 10), protected and non-protected from potential predators. Predation, removal and germination were then followed. After 107 days, 100 % of the exposed seeds were removed/predated and none germinated. For seed removal, we found differences among topographic positions and seed densities with higher removal (up to 80 %) and lower predation rates for grouped seeds. Germination was only observed for protected seeds with higher germination rates in single (17 % ± 9) than in grouped seeds (4 % ± 1). The highest germination and establishment rates were adjacent to the streams; areas which had the lowest light intensity (mean ± SE = 883 ± 160 lm/ft2) and temperatures (mean ± SE = 20.1 ± 0.6 °C), and highest humidity (mean ± SE = 50.8 ± 1.8 %), especially during the rainy season. Differential seedling establishment rates across the landscape due to spatial patterns of seed predation/removal as well as micro-environmental variables appear to have implications for shaping the spatial structure of B. aculeata population at Sierra de Alamos, Mexico.

This quasi-experimental study investigated the effects of client education with telephone follow-up on adherence to self-management among diabetics. Purposive sampling was utilized to choose the 79 participants of the study, and was divided into control and experimental group through cast lots. At pre-test, both the control and experimental groups have moderate adherence to blood glucose monitoring practices, medication management, and foot care practices, while fasting blood glucose was high. At post-test, the experimental group adherence to medication management and foot care practices was high, while blood glucose monitoring practices remained moderate, and fasting blood glucose was still high. There was no significant difference in the pre-test adherence level to self-management among the control and experimental group in terms of blood glucose monitoring practices, fasting blood glucose, medication management, and foot care practices. There was a significant difference in the pre-and-post-test adherence to self-management among the control and experimental group; however, in the control group, medication management is not significant. There was significant difference in the gain score in terms of blood glucose monitoring, medication management, and foot care practices between the control group and the experimental group. Those who are female, younger, and diagnosed to have diabetes for less than five years are more adherent to self-management.

To understand the population dynamics of a species, it is necessary to document the way in which its demographic behaviour varies through space and time. Anthropogenic disturbance, such as shifting cultivation, is an important factor causing demographic variation in many tropical non-timber forest products. The leaves of the palm Sabal yapa are an important non-timber forest product used for thatching by Mayan peoples. The demography of Sabal yapa was studied in three habitats (mature forest, successional forest and crop fields), representing successional phases along the slash-and-burn agricultural cycle in the Yucatan Peninsula. Matrix population models, along with elasticity analyses and life-table-response experiments were employed. Population growth rate differed between patches (MF: λ = 1.043; SF: λ = 1.027; CF: λ = 0.959). Only the λ value of the mature forest was significantly higher than unity. Fecundity and seedling survival were lowest in the crop fields and highest in the mature forest. The elasticity analyses and life-table-response experiments showed that entries with a high positive contribution to λ also showed high elasticity values, while those with a negative contribution to λ showed low elasticity. Thus, both analyses are crucial to understand the demography of a species and to aid in conservation and management practices.

Understanding the effect of agriculture on the availability of non-timber forest products (NTFP) is currently relevant. Many landscapes are dominated by agricultural fields and fallow lands, so we should understand the status of NTFP in these landscapes. We studied the availability of leaves of xa'an palm trees (Sabal yapa Wright ex Beccari) in the shifting cultivation systems among the Yucatec Maya in Mexico. The mature leaves of this species of palm have been widely used for roofing since prehispanic times until present days; in the year 2000, approximately 90,000 people used S. yapa in Quintana Roo, and 360,000 used Sabal spp. in the Yucatan peninsula. This palm is managed by Maya farmers who spare palm trees when clearing a forest patch to turn it into maize fields (milpa). We compared the population structure and leaf production rate in differentstages of theshiftingcultivation cycle (milpa, fallowlandsand forest), and quantified thedomestic leaf demandinthevillage of X-Maben, state of Quintana Roo. In addition, we projected future availability of xa'anleaves,and estimated the period after which this might not be sufficient enough to cover the local demand of somevillages and municipalities of Quintana Roo. Our results suggest that one of the consequences of shifting cultivation is the decrease in the availability and quality of this NTFP. Decreasing availability is a result of variations in population structure and leaf production rates between agriculture and forest patches. These negativeeffects may increase as agriculture becomes more intensive.Currently, the complete mosaic landscape created by this practice still offers sufficient resources for the local inhabitants in many communities. Besides, this NTFP has a high commercial potential in the tourist area. Our study suggests that the harvest of S. yapa in natural systems is sustainable for nine more decades and will be compatible with shifting cultivation as long as land tenure remains communal, there are long fallow periods and other factors remain unchanged. # 2005 Elsevier B.V. All rights reserved.

Mexico has the second largest cycad diversity in the world, and the Sierra Madre Oriental (SMO) is one of the richest biogeographic regions for these plants. Despite there is a general Cycad National Program in the country, there are no state-level cycad conservation strategies or programs. Thus the aim of this study was to propose a cycad conservation strategy for the state of Hidalgo, which is located in the Southern part of the SMO. For this, a cycad species inventory was made in the state, for which three methods were used: review of published literature; consultation in the main Mexican herbaria to verify botanical specimens; and exhaustive field research to compare findings with previously reported species and to recognize new records at the county and state level. The proposed research work strategy combined the following elements: prioritize the county and local areas with greatest cycad species richness; prioritize the species least resistant to environmental change and/or having restricted geographic distribution; and to consider the main uses of these plants by local residents. The results showed that Hidalgo has three genera and eight species of cycads: Ceratozamia fuscoviridis, C. latifolia, C. mexicana, C. sabatoi, Dioon edule, Zamia fischeri, Z. loddigesii and Z. vazquezii, all of which are considered by the International Union for Conservation of Nature (IUCN). This study added two new species records for Hidalgo and 21 at the county level. The species are distributed in 26 counties, of which Chapulhuacan and Pisaflores are notable for their high species richness. Hidalgo has the fourth-greatest cycad species richness among Mexican states, although its area accounts for only 1.07% of the country. The state’s diversity is greater than in other states with larger area, and even than in some other entire countries in Mesoamerica. The presented state cycad conservation strategy proposes that a total of some 11 325ha to be conserved in nine zones, including different vegetation types, distributed in seven counties. The strategy involves a mixed scheme that incorporates conservation in Protected Natural Areas (ANP), Small Farmer Reserves (Reservas Campesinas) and Environmental Management Units (UMA in Spanish). This proposal will be useful for government agencies to take into account in the process of designating land use for the Cloud Forest Biological Corridor (CBBMM in Spanish), a ANP in creation. The state of Hidalgo urgently needs a detailed analysis of trends in changes in vegetation cover and land use, and demographic studies of the cycads. It is recommended that the implementation phase of this state strategy be carried out jointly with local communities, academia, and state and federal agencies responsible for biodiversity conservation.

Mexico has the second largest cycad diversity in the world, and the Sierra Madre Oriental (SMO) is one of the richest biogeographic regions for these plants. Despite there is a general Cycad National Program in the country, there are no state-level cycad conservation strategies or programs. Thus the aim of this study was to propose a cycad conservation strategy for the state of Hidalgo, which is located in the Southern part of the SMO. For this, a cycad species inventory was made in the state, for which three methods were used: review of published literature; consultation in the main Mexican herbaria to verify botanical specimens; and exhaustive field research to compare findings with previously reported species and to recognize new records at the county and state level. The proposed research work strategy combined the following elements: prioritize the county and local areas with greatest cycad species richness; prioritize the species least resistant to environmental change and/or having restricted geographic distribution; and to consider the main uses of these plants by local residents. The results showed that Hidalgo has three genera and eight species ofcycads: Ceratozamia fuscoviridis, C. latifolia, C. mexicana, C. sabatoi, Dioon edule, Zamia fischeri, Z. loddigesii and Z. vazquezii, all of which are considered by the International Union for Conservation of Nature (IUCN). This study added two new species records for Hidalgo and 21 at the county level. The species are distributed in 26 counties, of which Chapulhuacán and Pisaflores are notable for their high species richness. Hidalgo has the fourth-greatest cycad species richness among Mexican states, although its area accounts for only 1.07% of the country. The state's diversity is greater than in other states with larger area, and even than in some other entire countries in Mesoamerica. The presented state cycad conservation strategy proposes that a total of some 11,325 ha to be conserved in nine zones, including different vegetation types, distributed in seven counties. The strategy involves a mixed scheme that incorporates conservation in Protected Natural Areas (ANP), Small Farmer Reserves (Reservas Campesinas) and Environmental Management Units (UMA in Spanish). This proposal will be useful for government agencies to take into account in the process of designating land use for the Cloud Forest Biological Corridor (CBBMM in Spanish), a ANP in creation. The state of Hidalgo urgently needs a detailed analysis of trends in changes in vegetation cover and land use, and demographic studies of the cycads. It is recommended that the implementation phase of this state strategy be carried out jointly with local communities, academia, and state and federal agencies responsible for biodiversity conservation.

Shifting cultivation is often perceived to be a threat to forests, but it is also central to the culture and livelihoods of millions of people worldwide. Balancing agriculture and forest conservation requires knowledge of how agricultural land uses evolve in landscapes with forest conservation initiatives. Based on a case study from Quintana Roo, Mexico, and remote sensing data, we investigated land use and land cover change (LUCC) in relation to accessibility (from main settlement and road) in search of evidence for agricultural expansion and/or intensification after the initiation of a community forestry program in 1986. Intensification was through a shortening of the fallow period. Defining the sampling space as a function of human needs and accessibility to agricultural resources was critical to ensure a user-centered perspective of the landscape. The composition of the accessible landscape changed substantially between 1976 and 1997. Over the 21-year period studied, the local population saw the accessible landscape transformed from a heterogeneous array of different successional stages including mature forests to a landscape dominated by young fallows. We detected a dynamic characterized by intensification of shifting cultivation in the most accessible areas with milpas being felled more and more from young fallows in spite of a preference for felling secondary forests. We argue that the resulting landscape provides a poorer resource base for sustaining agricultural livelihoods and discuss ways in which agricultural change could be better addressed through participatory land use planning. Balancing agricultural production and forest conservation will become even more important in a context of intense negotiations for carbon credits, an emerging market that is likely to drive future land changes worldwide.

5-HT(4) receptor agonists are used therapeutically to treat disorders of reduced gastrointestinal motility. Since such compounds are evaluated in guinea-pigs, we cloned, expressed and pharmacologically characterized the guinea-pig 5-HT(4) and human 5-HT(4(b)) splice variant, which share 95% homology. The functional properties of guinea-pig 5-HT(4(b)) receptors were compared with native receptors in guinea-pig colon.Membrane radioligand binding and whole cell cAMP accumulation assays were used to determine the affinities, potencies and intrinsic activities (IA). Contraction of the guinea-pig distal colon longitudinal muscle myenteric plexus preparation (LMMP) was monitored to evaluate functional activity.pK(i) values for guinea-pig and human recombinant receptors, and guinea-pig striatum 5-HT(4) receptors, were in agreement, as were the potency and IA values for guinea-pig and human 5-HT(4) receptors expressed at a similar density ( approximately 0.2 pmol mg(-1) protein). Tegaserod was a potent (pEC(50)=8.4 and 8.7, respectively), full agonist at both guinea-pig and human 5-HT(4) receptors. In contrast, in the LMMP preparation, tegaserod was a potent, partial agonist (pEC(50)=8.2; IA=66%).Close agreement between the pharmacological properties of guinea-pig and human 5-HT(4) receptors support the use of guinea-pig model systems for the identification of 5-HT(4) receptor therapeutics. However, the mechanisms underlying the different agonist properties of tegaserod in recombinant and isolated tissue preparations, and the extent to which these impact the clinical efficacy of tegaserod as a prokinetic agent, remain to be determined.

In recent years new therapeutic options have been developed for the management of pulmonary arterial hypertension (PAH). Sitaxsentan is an oral, once daily, highly selective endothelin A receptor antagonist that recently demonstrated a positive effect on functional capacity and haemodynamics of PAH patients. The aim of this study is to evaluate the effect of sitaxsentan in the quality of life (QOL) of PAH patients. Twenty-three patients with idiopathic PAH or PAH associated to collagen vascular diseases were evaluated at baseline and after 16 weeks of treatment with sitaxsentan 100 mg orally, once daily. 6-min walk test distance (6MWD) and QOL questionnaire (QOLQ) (SF-36) were obtained at baseline and at week 16. There was a significant improvement in functional capacity evaluated by 6MWD (472 m vs. 490 m, p = 0.03) and also in the physical component of the QOLQ (p0.01). Evaluating each of the domains of the SF-36 QOLQ, those more related to physical capacity presented a significant increase while the domains related to the mental component presented a trend of improvement, without reaching statistical significance. Sitaxsentan improves QOL in patients with PAH mainly through the domains related to functional capacity.

The current dataset evidences that the morphological variability observed in leaves and fruits of Colombian oak is continuous. It reflects the presence of only one single species of oak in this country — Quercus humboldtii. Current molecular data support this hypothesis. However, more detailed molecular analysis should be done in order to draw firmer conclusions. Similarly, more specific research should be conducted to find out if floristic richness of oak forest in Colombia is really as low as past, limited studies report.

1 Tegaserod (Zelnorm) is a potent 5-hydroxytryptamine4 (5-HT4) receptor agonist with clinical efficacy in disorders associated with reduced gastrointestinal motility and transit. The present study investigated the interaction of tegaserod with 5-HT2 receptors, and compared its potency in this respect to its 5-HT4 receptor agonist activity. 2 Tegaserod had significant binding affinity for human recombinant 5-HT2A, 5-HT2B and 5-HT2C receptors (pKi=7.5, 8.4 and 7.0, respectively). The 5-HT2B receptor-binding affinity of tegaserod was identical to that at human recombinant 5-HT4(c) receptors (mean pKi=8.4) in human embryonic kidney-293 (HEK-293) cells stably transfected with the human 5-HT4(c) receptor. 3 Tegaserod (0.1-3 microm) inhibited 5-HT-mediated contraction of the rat isolated stomach fundus potently (pA2=8.3), consistent with 5-HT(2B) receptor antagonist activity. Tegaserod produced, with similar potency, an elevation of adenosine 3',5' cyclic monophosphate in HEK-293 cells stably transfected with the human 5-HT4(c) receptor (mean pEC50=8.6), as well as 5-HT4) receptor-mediated relaxation of the rat isolated oesophagus (mean pEC50=8.2) and contraction of the guinea-pig isolated colon (mean pEC50=8.3). 4 Following subcutaneous administration, tegaserod (0.3 or 1 mg kg(-1)) inhibited contractions of the stomach fundus in anaesthetized rats in response to intravenous dosing of alpha-methyl 5-HT (0.03 mg kg(-1)) and BW 723C86 (0.3 mg kg(-1)), selective 5-HT2B receptor agonists. At similar doses, tegaserod (1 and 3 mg kg(-1) subcutaneously) evoked a 5-HT4 receptor-mediated increase in colonic transit in conscious guinea-pigs. 5 The data from this study indicate that tegaserod antagonizes 5-HT2B receptors at concentrations similar to those that activate 5-HT4 receptors. It remains to be determined whether this 5-HT2B receptor antagonist activity of tegaserod contributes to its clinical profile.

Several animal models of right ventricle hypertension (RVH) have been produced through pulmonary artery banding with linen, tygon or teflon. Nevertheless few devices attempting a progressive, step by step graduated chronic development of RVH have been reported. The present study describes the results in our animal model of chronic RVH.We designed a software programmed to obtain hemodynamic data and installed a small occlusive hydraulic device (OHD) at the pulmonary artery trunk producing a raise in the right ventricular systolic pressure (RVSP); this pressure can be modified externally through the OHD. We studied 12 healthy mongrel dogs (18 to 28 kg of weight) in the course of 6 months. Hemodynamic measurements were performed at different RVSP at two months intervals; (Baseline, 40 mmHg and 60 mmHg).The software was useful to analyze several hemodynamic variables at each RVSP. At 60 mmHg, the end diastolic pressure of the right ventricle (RVEDP) increased from 4.2 +/- 0.4 mmHg to 13.2 +/- 1.1 mmHg, p0.000, accompanied with a fall in cardiac output adjusted to the dogs weight from 0.16 +/- 0.03 L/min/kg to 0.09 +/- 0.01 L/min/kg, p0.000. Also an increase of the end diastolic pressure of the left ventricle (LVEDP) from 7.4 +/- 0.8 mmHg to 16.3 +/- 2.8 mmHg, p0.000, was observed. RVSP was maintained in chronic condition and the intraclass correlation coefficient was 0.83, P0.005.Right ventricular chronic hypertension is created. The device is useful and reliable to maintain chronic increments of RVSP. The software permits a versatile analysis.

Primary pulmonary hypertension (PPH) is a rare, progressive and fatal condition. Because of nonspecific signs and symptoms, patients diagnosed with PPH are often present with a relatively advanced disease. Significant advances have been made in recent years. A revised nomenclature has been proposed, the pathobiology is now better defined, new risk factors have been identified, and the newer therapeutic strategies appear to be changing the natural history and prognosis of this disease.

We assessed the diagnostic usefulness of helical CT scan of the thorax in the setting of chronic thromboembolic pulmonary hypertension by prospectively comparing the results of helical CT scan to those of the pulmonary angiogram (gold standard). We studied 40 patients with diagnosis of pulmonary hypertension of diverse etiology (mean age: 40.7 +/- 12 y.o.; mean systolic pulmonary artery pressure: 91 +/- 33 mmHg)). Thirty of these patients fulfilled the diagnostic criteria of chronic thromboembolic pulmonary hypertension and the other ten were used as controls. Diagnosis in control patients included: primary pulmonary hypertension (4); patent ductus arteriosus (2); atrial septal defect (1); rheumatic valve disease (1); ischemic heart disease (1); and acute pulmonary embolism (1). Both helical CT scan and pulmonary angiogram were part of the routine diagnostic work up of these patients, and were, performed and interpreted almost simultaneously (within one week) by a different group of investigators in a blind manner. Only the diagnostic accuracy of the method regarding central (major arteries) vascular lesions was evaluated. Helical CT scan had an overall sensitivity of 100% (29/29), and a specificity of 91% (10/11). Positive predictive and negative predictive values were 96.6% (29/30) and 100% (10/10), respectively. Overall diagnostic accuracy was 97.5% (39/40). We conclude that helical CT scan of the thorax is an excellent alternative approach for the diagnosis of major arteries lesions in the setting of chronic thromboembolic pulmonary hypertension.

We sought to investigate the acute hemodynamic effects of graded balloon dilation atrial septostomy (BDAS) and to define the long-term impact of this procedure on New York Heart Association functional class and survival in adult patients with primary pulmonary hypertension (PPH).Current treatment strategies for patients with severe and refractory PPH are limited by either technical difficulties and high mortality or cost.We studied 15 patients with severe PPH. BDAS was successfully performed in all patients by crossing the interatrial septum with a Brockenbrough needle, followed by progressive dilation of the orifice with a Mansfield balloon in a hemodynamically controlled, step-by-step manner.BDAS caused an immediate significant fall in right ventricular end-diastolic pressure and in systemic arterial oxygen saturation and an increase in cardiac index. One patient died, and 14 survived the procedure and significantly improved their mean functional class (from 3.57 +/- 0.6 to 2.07 +/- 0.3 [mean +/- SD], p0.001). Exercise endurance (6-min test) also improved from 107 +/- 127 to 217 +/- 108 m (p0.001). Because of spontaneous closure, BDAS was repeated in four patients. The survival rate among patients who survived the procedure was 92% at 1, 2 and 3 years, which is better than that for historical control PPH patients (73%, 59% and 52%, respectively).With careful monitoring, BDAS is a safe and useful palliative treatment for selected patients with severe PPH.

5-HT4 receptors in isolated distal colon myenteric plexus of guinea-pig, mediating contraction of longitudinal smooth muscle, have been further characterized by selective agonists and antagonists. The indole agonists, 5-HT and 5-methoxytryptamine (5-MeOT), were full agonists (relative to 5-HT) with potency values (pEC50) of 8.0 +/- 0.1 (n = 50) and 7.8 +/- 0.1 (n = 12), respectively. 5-HT4 receptor agonists of other structural classes, including benzimidazolones (BIMU 1 and BIMU 8), and benzamides ((S)-zacopride, (R)-zacopride, renzapride, SC 49518) were partial agonists with intrinsic activities less than that of 5-HT. In general, the potencies for these compounds at 5-HT4 receptors in guinea-pig colon were similar to the potencies seen in the rat isolated oesophagus, where 5-HT4 receptors mediate relaxation. GR 113808 ¿[1-[2-[(methylsulfonyl)amino]ethyl]-4-piperidinyl] methyl1-methyl-1H-indole-3-carboxylate¿, RS 39604 ¿1-[4-amino-5-chloro-2-(3, 5-dimethoxybenzyloxy)phenyl]-3[1-[2-[(methylsulfonyl)amino] ethyl]-4-piperidinyl]-1-propanone hydrochloride and SB 204070 ¿(1-n-butyl-4-piperidinyl)methyl 8-amino-7-chloro-1, 4-benzodioxane-5-carboxylate¿ antagonized 5-HT responses with pA2 values of 9.1 +/- 0.1, 9.0 +/- 0.2 and 11.0 +/- 0.1, respectively. These affinity values were similar to those obtained at 5-HT4 receptors in isolated rat oesophagus (9.0+/- 0.4, 9.3 +/- 0.1 and 10.6 +/- 0.1 respectively). Despite these operational similarities between 5-HT4 receptors in guinea-pig colon and rat oesophagus, several novel compounds have revealed important differences between 5-HT4 receptors in the two tissues. For example, the substituted benzoate, RS 23597 ¿3-(piperidine-1-yl) propyl-4-amino-5-chloro-2-methoxybenzoate hydrochloride, acted as a partial agonist (intrinsic activity 0.5) in guinea-pig colon with a potency of 7.6 +/-0.1 (n = 16). In isolated rat oesophagus, however, this compound was a surmountable antagonist (pA2 = 7.8 +/- 0.1) with no intrinsic activity. In contrast, the substituted naphthalimide (S)RS 56532 ¿(S)-6-amino-5-chloro-2-(1-azabicyclo[2, 2, 2]octan-3-yl) 2,3-dihydro-1H-benz[de] isoquinoline-1,3-dione hydrochloride¿, was a potent (pEC50 = 7.9 +/- 0.1), efficacious partial agonist (intrinsic activity = 0.8) in the rat oesophagus. However, in guinea-pig colon, it was a surmountable antagonist with an affinity (pKB) of 9.4 +/- 0.1. Furthermore, several novel, selective, 5-HT4 compounds also showed opposing patterns of intrinsic activities similar to those described for RS 23597 and (S)RS 56532. It is concluded that these differences are inconsistent with differences in 5-HT4 receptor reserves, and may suggest that 5-HT4 receptors in the guinea-pig colon and the rat oesophagus can be operationally distinguished.