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BACKGROUND AND AIMS: Aridity is increasing in many regions of the world, but microclimatic conditions may buffer plant communities from the direct effects of decreased precipitation, creating habitat islands. However, reduced precipitation can also impact these communities indirectly by decreasing the suitability of the surrounding habitat, thus limiting incoming propagules and increasing the chances of population decline and species loss. We test whether decreased precipitation results in loss of species and functional diversity within habitat islands, evaluating in particular whether declines in species diversity and abundance are less likely to result in loss of functional diversity if species/individual loss is stochastic (i.e. independent of species/individual traits) and communities/populations are functionally redundant. METHODS: Lomas communities are discrete plant communities embedded in the Atacama Desert, maintained by the microclimatic conditions created by fog. We recorded species and functional diversity in six Lomas communities along a 500 km long precipitation gradient in northern Chile. Functional traits were measured in 20 individuals per species, in those species that accounted for approx. 75 % of the abundance at each site. We calculated functional diversity and functional redundancy of the community, and intraspecific functional variation. KEY RESULTS: Decreased precipitation was associated with lower species diversity and lower species abundances. However, no traits or functional strategies increased or decreased consistently with precipitation, suggesting stochastic species/individual loss. Species with stress-tolerant strategies were predominant in all sites. Although species diversity decreased with decreasing precipitation, functional diversity remained unchanged. Lower functional redundancy in the drier sites suggests that mainly functionally redundant species were lost. Likewise, intraspecific functional variation was similar among communities, despite the lower species abundance in drier sites. CONCLUSIONS: Decreased precipitation can impact habitat island communities indirectly by decreasing the suitability of the surrounding habitat. Our results support the idea that a stochastic loss of species/individuals from functionally redundant communities and populations does not result in loss of functional diversity.

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In this article we present a compilation of U-Pb zircon ages of the whole Xolapa terrane in coastal southern Mexico (dataset 1) as a curved line, obtained from plotting individual zircon grains versus its corresponding age. We identified five low-slope segments of the curved line, each one assigned to a high zircon-production (or preservation) event (HZE). Crystallization temperatures (CT) from Ti-in-zircon geothermometer data on Xolapa rocks were estimated separately from individual zircon grains (dataset 2), in order to compare CT ranges corresponding to each HZE identified. Datasets 1 and 2 are discussed for tectonic implications in the research article "The opening and closure of the Jurassic-Cretaceous Xolapa basin, southern Mexico" Peña-Alonso et al., 2017.

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Introduction: Potentially hepatotoxic drugs are used in tuberculosis treatment. The incidence range of drug-induced liver injury (DILI) varies from 0.6 to 33 percent. Adverse reactions can be asymptomatic; therefore periodical liver tests are required. Multiple risk factors are described, such as age and HIV infection, among others. Objective: To determine risk factors associated to DILI and secondary lethality in patients receiving anti-tuberculosis drugs. Materials and Methods: The database from the Servicio de Salud Metropolitano Central de Chile was used. 1,249 patients were analyzed from 2003 to 2008 to determine DILI’s frequency and time of appearance. Multivariate binominal regression was used to study possible risks associated to hepatotoxicity. Results: 2,8 percent of our patients presented DILI (n = 35), three of them died from this cause (8.5 percent). Association between DILI and HIV infection and extrapulmonary tuberculosis was observed (p < 0.01). DILI was present in 50 percent of our patients before the 23rd day. Conclusions: We propose a more exhaustive control of the liver function in patients with DILI risk factors, including HIV carriers and extrapulmonary tuberculosis.

Introducción: El tratamiento antituberculosis incluye drogas hepatotóxicas, estimándose una incidencia de daño hepático inducido por medicamentos (DHIM) entre 0,6 y 33 por ciento. Puede ser asintomático, debiendo evaluarse periódicamente con perfil hepático. Se han descrito múltiples factores de riesgo, como mayor edad e infección por VIH, entre otros. Objetivo: Determinar factores asociados al desarrollo de DHIM y letalidad secundaria a tratamiento antituberculosis. Materiales y Métodos: Base de datos del Programa de Tratamiento antituberculosis del Servicio de Salud Metropolitano Central de Chile. Se analizaron 1.249 pacientes entre 2003 y 2008. Se determinó frecuencia y tiempo de aparición de DHIM. Se estudiaron posibles factores asociados a hepatotoxicidad mediante regresión binomial. Resultados: se diagnosticó DHIM en 2,8 por ciento de los pacientes (n = 35), falleciendo 3 de ellos por esta causa (8,5 por ciento). Se observó asociación entre DHIM con ser portador de VIH (+) y tuberculosis extrapulmonar (p < 0,01). Aparición de DHIM antes del día 23 en 50 por ciento de los casos. Conclusión: Sugerimos un control más exhaustivo del perfil hepático en pacientes con factores de riesgo, entre los cuales deben considerarse los portadores de VIH y tuberculosis extrapulmonar.

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El melanoma es un cáncer que afecta principalmente a la piel. La Organización Mundial de la Salud estima que las cifras de incidencia y mortalidad anual son 2,8 y 0,6 por ciento habitantes, respectivamente. El presente trabajo pretendió revisar la información científica publicada sobre incidencia y sobrevida, y analizar la mortalidad (desde 1983 al 2008). La tasa de incidencia estandarizada estimada para el año 2008 fue 2,2, ese mismo año la tasa de mortalidad estandarizada fue 0,65. Entre 1983 y 2008 la tasa de mortalidad promedio fue 0,77, observándose un 25 por ciento de aumento, estadísticamente significativo. En cuanto a sobrevida, solo hay trabajos locales donde se observa que ésta oscila entre 100 por ciento y 33 por ciento a los 5 años de acuerdo al nivel de Clark y estadío TNM. En general, hay escasa información sobre la epidemiología del melanoma en Chile. Se requieren más estudios y focalizar las estrategias en la prevención.

Melanoma affects mainly the skin. The World health Organization estimates that standardized incidence and mortality rates are 2.8 an 0.6 percent inhabitants respectively. This study reviewed the published scientific information regarding incidence and survival and analyzed mortality data from 1983 to 2008. 2008 standardized incidence rate was 2.2 percent inhabitants and standardized mortality rate for the same year was 0.65. Mean mortality rate from 1983 to 2008 was 0.77. A 25 percent increase was found. Regarding survival, only local data is available and it ranged from 100 percent to 33 percent according to Clark Level and TNM classification. Melanoma epidemiology information is scarce in Chile. More studies are needed and prevention strategies must be implemented.

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In recent years, Brazilian Nuclear Programme has been reviewed and updated by government authorities in face of the demand for energy supply and its associated environmental constraints. The immediate impact of new national programmes and projects in nuclear field is the increase in the number of exposed personnel and the consequent need for reliable dosimetry services in the country. Several Technical Documents related to internal dosimetry have been released by the International Atomic Energy Agency and International Commission on Radiological Protection. However, standard bioassay procedures and methodologies for bioassay data interpretation are still under discussion and, in some cases, both in routine and emergency internal monitoring, procedures can vary from one laboratory to another and responses may differ markedly among Dosimetry Laboratories. Thus, it may be difficult to interpret and use bioassay data generated from different laboratories of a network. The main goal of this work is to implement a National Network of Laboratories aimed to provide reliable internal monitoring services in Brazil. The establishment of harmonised in vivo and in vitro radioanalytical techniques, dose assessment methods and the implementation of the ISO/IEC 17025 requirements will result in the recognition of technical competence of the network.

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Background: Adult women with adrenal congenital hyperplasia (AH) have a higher risk for insulin resistance, dyslipidemia, hypertension, high body mass index (BMI) and increased body fat. All these factors are associated with cardiovascular risk and metabolic syndrome (MS). Aim: To evaluate the presence of MS in pubertal classic AH girls (CAH) and a control group (C). Material and Methods: We studied 15 pubertal AH patients (12.0 +/- 1.9 years) and 26 controls (11.7+/- 0.3 years) matched by age and tanner stage. Weight, height, BMI, waist/hip ratio, blood pressure and serum lipids were measured. An oral glucose tolerance test (OGTT) and insulin curve was performed in CAH girls whereas in controls basal insulin and glucose were determined. The homeostasis model assessment for insulin resistance (HOMAIR) was calculated. Cook, Ferranti and international diabetes federation (IDF) criteria were used to determine the presence of MS. Results: CAH and C girls had similar BMI (22.0 +/- 5.1 and 20.1 +/- 3.6 kg/m2 respectively; p = 0,11). CAH girls had higher basal blood glucose (80.8 +/- 7.7 and 60.6 +/- 10.6 mg/dl respectively, p < 0.01) and controls had higher triglyceride levels (147.0 +/- 69.3 and 79.7 +/-16.3 mg/dl respectively, p < 0.01) and lower HDL cholesterol levels (45.8 +/- 12.8 and 56.9 +/- 17.5 mg/dl respectively, p = 0.02). According to cook criteria 4 percent of CAH girls and 23 percent of controls has MS. These figures were 14 and 32 percent respectively according to Ferranti criteria and 0 and 5 percent respectively according to IDF criteria. Conclusions: CAH puberal patients do not have a higher prevalence of metabolic syndrome, compared with controls with similar Tanner stage and BMI.

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The content and composition of neutral lipids and phosphoglycerides from full-grown prophase-arrested Bufo arenarum Hensel oocytes and from their ghost preparations were studied. The ghosts obtained are highly enriched in plasma membrane as suggested by the activity of 5'-nucleotidase, a marker enzyme, and the level of typical membrane components such as sphingomyelin, phosphatidylserine (PS), phosphatidylinositol (PI), and phosphatidic acid. In whole oocytes, triacylglyceride (TAG) comprises about 60% of the total lipids followed by phosphatidylcholine (PC), cholesterol, and phosphatidylethanolamine (PE). TAG and diacylglycerides have a similar unsaturation index. PC and PE account for about 80% of the phosphoglycerides in the whole oocyte and in their plasma membrane-enriched fractions. Arachidonic acid (20:4n-6), 18:0, and 16:0 make up about 80 mol% of the total fatty acids in PI in whole oocytes and ghost fractions. The unsaturation index in PS is higher in intact oocytes than in ghost preparations, probably owing to the significant amount of 20:4n-6 which comprises 23 mol% of the total fatty acids in whole oocytes. The fatty acid profile in phosphatidic acid from whole oocytes is rather different from that in ghosts. Sphingomyelin contains mainly saturated and monounsaturated fatty acids, 24:1 being the principal very long chain unsaturated fatty acid in both oocytes and ghosts.

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1. Polyphosphoinositide content and phosphorylation of lipids and proteins were analyzed in oocytes of the toad Bufo arenarum Hensel. 2. Plasma membrane-enriched fractions obtained from full-grown, prophase-arrested oocytes incorporated 32P into both phospholipids and proteins after incubation with [gamma-32P]ATP in an Mg(2+)-containing medium. Phosphatidylinositol 4-phosphate (PIP), phosphatidate (PA) and phosphatidylinositol-4,5-bisphosphate (PIP2) were the only labelled lipids. The 32P incorporation depended on incubation time, the amount of protein, and the ATP concentration. 3. Autoradiography of polyacrylamide gel electropherograms and scintillation counting showed that the radioactivity was mainly associated with a group of membrane proteins having an M(r) of 87,000. 4. This paper provides evidence for the capacity of prophase-arrested oocytes from Bufo arenarum to synthesize polyphosphoinositides and to phosphorylate distinct membrane proteins.

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