Water availability and population origin affect the expression of the tradeoff between reproduction and growth in Plantago coronopus.

Investment in reproduction and growth represent a classic tradeoff with implication for life history evolution. The local environment can play a major role in the magnitude and evolutionary consequences of such a tradeoff. Here, we examined the investment in reproductive and vegetative tissue in 40 maternal half-sib families from four different populations of the herb Plantago coronopus growing in either a dry or wet greenhouse environment. Plants originated from populations with an annual or a perennial life form, with annuals prevailing in drier habitats with greater seasonal variation in both temperature and precipitation. We found that water availability affected the expression of the tradeoff (both phenotypic and genetic) between reproduction and growth, being most accentuated under dry condition. However, populations responded very differently to water treatments. Plants from annual populations showed a similar response to drought condition with little variation among maternal families, suggesting a history of selection favouring genotypes with high allocation to reproduction when water availability is low. Plants from annual populations also expressed the highest level of plasticity. For the perennial populations, one showed a large variation among maternal families in resource allocation and expressed significant negative genetic correlations between reproductive and vegetative biomass under drought. The other perennial population showed less variation in response to treatment and had trait values similar to those of the annuals, although it was significantly less plastic. We stress the importance of considering intraspecific variation in response to environmental change such as drought, as conspecific plants exhibited very different abilities and strategies to respond to high versus low water availability even among geographically close populations.

Chlorhexidine Inhibits the Proteolytic Activity of Root and Coronal Carious Dentin in vitro.

The purpose of this study was to evaluate the effect of chlorhexidine on the proteolytic activity of carious coronal and root dentin collected from patients. Sound dentin from freshly extracted human teeth was used as a control. Dentin fragments were mixed with a synthetic substrate for proteolytic enzymes (N-benzoyl-DL-arginine-naphthylamide--BANA) and the suspensions mixed with either 0.12% chlorhexidine digluconate or distilled water. These mixtures were incubated for 18 h at 37 degrees C, color was developed by the addition of 0.1% Fast Garnet and their optical density was recorded spectrophotometrically. BANA hydrolysis measured by the optical density of incubated specimens was detected in all tested groups, but was significantly higher for carious than for sound dentin (p < 0.05). The proteolytic activity was reduced for carious coronal and root dentin by chlorhexidine (p < 0.05; 50 and 30%, respectively). Chlorhexidine also reduced the proteolytic activity in sound root dentin (p < 0.05; 20%). Conversely, changes in the proteolytic activity of sound coronal dentin were not observed in the presence of chlorhexidine. The reduction in proteolytic activity by chlorhexidine was significantly higher in carious coronal dentin than in carious root dentin (p < 0.05). In conclusion, part of the effect of chlorhexidine in controlling caries progression in humans may be due to a decrease in the proteolytic activity of carious coronal and root dentin. Because of the prolonged incubation time in the present study, similar results may be obtained clinically with prolonged dentin exposure to chlorhexidine, e.g. chlorhexidine-containing varnishes.

[Activity of Ertapenem and Ceftriaxone in the eradication of Salmonella in a model of experimental peritonitis in mice].

Since the beginning of the 1990s, the prevalence of isolates of non-typhoidal Salmonella species resistant to antimicrobial agents, including those commonly used for the treatment of Salmonella infections such as fluoroquinolones, trimethoprim-sulfamethoxazole or beta-lactams, has increased substantially. Infections caused by multidrug-resistant strains of non-typhoidal Salmonella are now frequently encountered. In order to consider an appropriate role of Ertapenem in Salmonella-due intraabdominal infections, in the present study we compare the efficacy of Ertapenem versus that of Ceftriaxone in a mouse peritonitis model. Bacteriological eradication from blood, liver and mesenteric lymph nodes was observed after 5 and 7 days of treatment in all infected mice receiving ceftriaxone. Although both antimicrobial agents -Ertapenem and Ceftriaxone- were observed to be effective in reducing mortality in inoculated mice, our data suggests a reduced efficacy of Ertapenem in the bacteriological eradication of Salmonella enterica serotype Typhimurium in a mouse peritonitis model.

Study and description of hydrogels and organogels as vehicles for cosmetic active ingredients.

Cellulite, a clinical syndrome mainly affecting women, involves specific changes in conjunctive dermic and subcutaneous tissue, leading to vascular and hypertrophic alterations in adipose tissues and the consequent alteration of tissue structure. This paper describes the design of hydrogels and pluronic-lecithin organogels elaborated as vehicles of Aloe vera (Aloe vera linné) and Hydrocotyle asiatica (Centella asiatica) for the treatment of cellulite. The objective of this work was to carry out a complete evaluation of the proposed formulae through the study of the organoleptic and rheological properties of the formulae. Our work revealed that, in appearance, hydrogels show better organoleptic characteristics than organogels. On the other hand, from a rheological point of view, both hydrogels and organogels display a plastic behavior. However, the main difference between the two is that the more complex internal structure of the organogel bestows it with more viscosity. Finally, in vitro tests with Franz-type diffusion cells revealed that the release of cosmetic active principle from the tested excipients was appropriate, both in terms of magnitude and velocity.

Life-history trade-offs vary with resource availability across the geographic range of a widespread plant.

Trade-offs between reproduction, growth and survival arise from limited resource availability in plants. Environmental stress is expected to exacerbate these negative correlations, but no studies have evaluated variation in life-history trade-offs throughout species geographic ranges. Here we analyse the costs of growth and reproduction across the latitudinal range of the widespread herb Plantago coronopus in Europe. We monitored the performance of thousands of individuals in 11 populations of P. coronopus, and tested whether the effects of growth and reproduction on a set of vital rates (growth, probability of survival, probability of reproduction and fecundity) varied with local precipitation and soil fertility. To account for variation in internal resources among individuals, we analysed trade-offs correcting for differences in size. Growth was negatively affected by previous growth and reproduction. We also found costs of growth and reproduction on survival, reproduction probability and fecundity, but only in populations with low soil fertility. Costs also increased with precipitation, possibly due to flooding-related stress. In contrast, growth was positively correlated with subsequent survival, and there was a positive covariation in reproduction between consecutive years under certain environments, a potential strategy to exploit temporary benign conditions. Overall, we found both negative and positive correlations among vital rates across P. coronopus geographic range. Trade-offs predominated under stressful conditions, and positive correlations arose particularly between related traits like reproduction investment across years. By analysing multiple and diverse fitness components along stress gradients, we can better understand life-history evolution across species' ranges, and their responses to environmental change.

Crosscultural adaptation and validation into Spanish of the questionnaire National Eye Institute Visual Function Questionnaire 25. / Adaptación cultural y validación al castellano del cuestionario National Eye Institute Visual Function Questionnaire 25.

INTRODUCTION: Advances in medicine have contributed to a higher average life expectancy, as well as an increasing number of chronic diseases patients. This longevity means that the assessment of the quality of life, particularly that related to vision, has become very relevant. OBJECTIVE: The validation of the translation and cross-cultural adaptation into Spanish of one of the most widely used vision-related quality of life questionnaires. It has sought to ensure that the Spanish version of the questionnaire was equivalent in semantic, conceptual, and technical content and criteria level, compared to its already validated English version. METHOD: An analytical observational study was conducted using a cohort of patients, in whom their quality of life related to vision was analysed. The study was developed in two steps; the first was the translation and cross-cultural adaptation to Spanish of the NEI VFQ-25 questionnaire. The second one was the psychometric study of the reliability and validity of the scale of the Spanish version. RESULTS: The analysis of the terms of reliability and validity showed that the translation and cross-cultural adaptation met the expected requirements and was well accepted by users. CONCLUSION: There is now a possibility of having a Spanish validated questionnaire available to assess the quality of life related to vision in patients with chronic diseases, such as age-related macular degeneration.

Streptavidin functionalized nickel nanowires: A new ferromagnetic platform for biotinylated-based assays.

Herein we present highly stable ferromagnetic nickel nanowires modified with streptavidin (NiNW-STR). This versatile functionalized nanomaterial works as an excellent biosensing platform for the immobilization of a wide range of biotinylated molecules. Moreover, these NWs can be employed in magnetic-based assays. Different proofs-of-concept such as streptavidin-biotin assays and capture of single and double stranded DNA were successfully carried out, corroborating NiNW-STR usefulness. Moreover, repeatability and stability studies were also effectively performed.

Silver electrodeposition catalyzed by colloidal gold on carbon paste electrode: application to biotin-streptavidin interaction monitoring.

A new electrochemical method to monitor biotin-streptavidin interaction on carbon paste electrode, based on silver electrodeposition catalyzed by colloidal gold, was investigated. Silver reduction potential changed when colloidal gold was attached to an electrode surface through the biotin-streptavidin interaction. Thus, the direct reduction of silver ions on the electrode surface could be avoided and therefore, they were only reduced to metallic silver on the colloidal gold particle surface, forming a shell around these particles. When an anodic scan was performed, this shell of silver was oxidized and an oxidation process at + 0.08 V was recorded in NH3 1.0 M. Biotinylated albumin was adsorbed on the pretreated electrode surface. This modified electrode was immersed in colloidal gold-streptavidin labeled solutions. The carbon paste electrode was then activated in adequate medium (NaOH 0.1 M and H2SO4 0.1 M) to remove proteins from the electrode surface while colloidal gold particles remained adsorbed on it. Then, a silver electrodeposition at -0.18 V for 2 min and anodic stripping voltammetry were carried out in NH3 1.0 M containing 2.0 x 10(-5) M of silver lactate. An electrode surface preparation was carried out to obtain a good reproducibility of the analytical signal (5.3%), using a new electrode for each experiment. In addition, a sequential competitive assay was carried out to determine streptavidin. A linear relationship between peak current and logarithm of streptavidin concentration from 2.25 x 10(-15) to 2.24 x 10(-12) M and a limit of detection of 2.0 x 10(15) M were obtained.

AC voltammetric carbon paste-based enzyme immunosensors.

Carbon paste electrodes, previously anodised in a basic media, are the basis for the development of a new voltammetric immunosensor device. Passive adsorption of the appropriate immunochemical reagent was performed onto the electrode surface. Alkaline Phosphatase labelled immunoglobulin was the tracer used in this work, 3-indoxyl phosphate being a very suitable enzymatic substrate for the electrochemical detection of the corresponding affinity reaction. The hydrolysis of this molecule generates indigo dimmer. This product was detected by alternating current voltammetry taking advantage of the adsorptive and inherent electrodic properties that it exhibits. The same electrochemical anodisation was used at the end of one assay to remove the entire protein layer attached to the carbon paste surface, allowing the formation of a new sensing phase and the use of the same support in several consecutive experiments. The methodology was applied to the design of two different immunoassays for the determination of human IgG. Good reproducibility of the electrodic signal and a limit of detection around 10(-10) M were achieved.

Colloidal gold as an electrochemical label of streptavidin-biotin interaction.

A new electrochemical method to monitor biotin-streptavidin interaction, based on the use of colloidal gold as an electrochemical label, is investigated. Biotinylated albumin is adsorbed on the pretreated surface of a carbon paste electrode (CPE). This modified electrode is immersed in colloidal gold-streptavidin labelled solutions. Adsorptive voltammetry is used to monitor colloidal gold bound to streptavidin, obtaining a good reproducibility of the analytical signal (R.S.D. = 3.3%). A linear relationship between peak current and streptavidin concentration from 2.5 x 10(-9) to 2.5 x 10(-5) M is obtained when a sequential competitive assay between streptavidin and colloidal gold-labelled streptavidin is carried out. On the other hand, the adsorption of streptavidin on the electrode surface was performed, followed by the reaction with biotinylated albumin labelled with colloidal gold. In this way, a linear relationship between peak current and colloidal gold labelled biotinylated albumin concentration is achieved with a limit of detection of 7.3 x 10(9) gold particles per ml (5.29 x 10(-9) M in biotin).

Basal cell adenoma of prostate.

A case of basal cell adenoma originating in the prostate is presented. This lesion might develop from proliferation of basal epithelial cells of the prostate gland under unknown mechanism.

Preparation of 2,3-seco-5 alpha-cholestane-2,3-diol and 4 alpha-methyl-2,3-seco-5 alpha-cholestane-2,3-diol and its reactions with o-nitrophenyl selenocyanate.

The reaction of 2,3-seco-5 alpha-cholestane-2,3-diol and 4 alpha-methyl-2,3-seco-5 alpha-cholestane-2,3-diol with o-nitrophenyl selenocyanate was studied. The diols were synthesized from cholesterol.

Trends in suicide in the elderly in Asturias (Spain).

Data from elderly suicides was obtained from two previous studies of community suicides in two localities of Northern Spain, namely, Oviedo between 1983 and 1990, and Gijón between 1975 and 1986. Data from the two localities were obtained by the revision of court register cases. A retrospective study on elderly suicide (over 60 years of age) was carried out. Mean annual specific rates for the elderly in Oviedo for 1982-1991 were 37.7 (58.1 for men and 23.3 for women) and for those in Gijón for the period 1975-1986, 23.4 (40 for men and 11.5 for women). A marked increase was seen in the rates for Gijón from the first (1975-1978) to the last period (1983-1986). This was particularly marked in men. The greatest increase in the rate was seen in men over 75 from Gijón and in those between 1970-1974 from Oviedo. In contrast a decrease was seen in the 65-69 age group rates for both men and women. A tendency for the rates to increase was seen but no important increase for elderly suicides was evident.

A model for clinical evaluation of the effect of antimicrobial agents on carious dentin.

PURPOSE: To evaluate, longitudinally, the effect of a chlorhexidine varnish on the proteolytic activity of dentin caries in vivo. MATERIALS AND METHODS: 20 permanent molars and 8 primary molars with carious lesions in dentin were studied in subjects 18-35 yrs old (n=20), and 5-6 yrs old (n=8) respectively. These lesions were clinically evaluated according to texture and color. Carious dentin specimens were obtained by means of biopsies performed with a #4 carbide bur at the initial visit (TO) before application of a 10% chlorhexidine varnish and 2, 4, 8, and 12 wks thereafter. The dentin biopsies were immersed in Sorensen's buffer, vortexed for 30 s, and mixed with a 1.67 mM solution of n-benzoyl-DL-arginine-naphthylamide (BANA), a substrate for proteolytic enzymes. Samples were incubated overnight at 37 degrees C and color was developed with 0.1% fast garnet. The optical density (OD) of reaction mixtures was recorded photometrically. All teeth were grouped for analysis, as Mann-Whitney tests revealed no statistically significant differences between median values for OD for both age groups. ANOVA was used to compare progressive inhibition of proteolytic activity in dentin caries samples over time. RESULTS: The average proteolytic activity at the dentin substrates (OD) at TO and 2, 4, 8 and 12 wks thereafter were 0.794+/-0.089, 0.741+/-0.071, 0.676+/-0.087, 0.600+/-0.094, and 0.508+/-0.108 respectively. The chlorhexidine varnish mediated a significant inhibition of the proteolytic activity present in dentin caries after 12 wks (P<0.0001). At T0, 100% of the carious lesions examined were characterized as soft upon exploration. After 12 wks, 54% (15/28) of the lesions were partially hardened and 46% (13/28) hardened/nonprogressing. The dentin color was yellow/light brown in 100% of the lesions at baseline, and dark brown/black in 86% (24/28) after 12 wks. CLINICAL SIGNIFICANCE: This study demonstrated that chlorhexidine varnishes arrested active caries in vivo and inhibited the proteolytic activity present in these lesions. These findings strengthen the rationale for including chlorhexidine in the overall treatment strategy for patients with high caries activity.

The role of the tolerance-fecundity trade-off in maintaining intraspecific seed trait variation in a widespread dimorphic herb.

Coexistence of species with different seed sizes is a long-standing issue in community ecology, and a trade-off between fecundity and stress tolerance has been proposed to explain co-occurrence in heterogeneous environments. Here we tested an intraspecific extension of this model: whether such trade-off also explains seed trait variation among populations of widespread plants under stress gradients. We collected seeds from 14 populations of Plantago coronopus along the Atlantic coast in North Africa and Europe. This herb presents seed dimorphism, producing large basal seeds with a mucilaginous coat that facilitates water absorption (more stress tolerant), and small apical seeds without coats (less stress tolerant). We analysed variation among populations in number, size and mucilage production of basal and apical seeds, and searched for relationships between local environment and plant size. Populations under higher stress (higher temperature, lower precipitation, lower soil organic matter) had fewer seeds per fruit, higher predominance of basal relative to apical seeds, and larger basal seeds with thicker mucilaginous coats. These results strongly suggest a trade-off between tolerance and fecundity at the fruit level underpins variation in seed traits among P. coronopus populations. However, seed production per plant showed the opposite pattern to seed production per fruit, and seemed related to plant size and other life-cycle components, as an additional strategy to cope with environmental variation across the range. The tolerance-fecundity model may constitute, under stress gradients, a broader ecological framework to explain trait variation than the classical seed size-number compromise, although several fecundity levels and traits should be considered to understand the diverse strategies of widespread plants to maximise fitness in each set of local conditions.

Conformational studies by dynamic NMR. 84.(1) structure, conformation, and stereodynamics of the atropisomers of N-aryl-tetrahydropyrimidines.

The existence of stereolabile atropisomers for a number of N-aryl-tetrahydropyrimidines in solution has been deduced from the observation of the anisochronous NMR signals of prochiral methylene groups. The interconversion barriers for these atropisomers have been measured by line shape analysis of dynamic NMR spectra at various temperatures: a Molecular Mechanics modeling resulted in good agreement with these values. In an appropriate case, distinct NMR signals for the two enantiomeric forms could be observed at ambient temperature in a chiral environment. Evidence was also obtained for an exchange process occurring between two conformers experiencing a very biased equilibrium. Single-crystal X-ray diffraction of one such compound yielded a molecular structure in good agreement with the results obtained by ab initio calculations.

Electrochemical behaviour of sertraline at a hanging mercury drop electrode and its determination in pharmaceutical products.

The electrochemical behaviour of sertraline at a hanging mercury drop electrode (HMDE) was described. Different voltammetric techniques, such as cyclic, linear sweep, differential pulse and square wave voltammetry, were used. Voltammograms were obtained at different pH values with a Britton-Robinson buffer solution used as supporting electrolyte. The best results were found by square wave voltammetry with electrodeposition at alkaline pH using a borate buffer with a pH = 8.2 for the samples, containing 12% (v/v) methanol. Under optimised conditions, a linear relationship between 2.33 x 10(-7) and 3.15 x 10(-6) M of sertraline with a limit of detection of 1.98 x 10(-7) M was obtained. The electrochemical method developed was applied to the determination of sertraline in pharmaceutical formulations. Recoveries were close to 100%, thus proving efficacy of the proposed method for the quantification of sertraline in commercial samples.

Acromegaly and hyperprolactinemia in a patient with polyostotic fibrous dysplasia: dynamic endocrine studies and treatment with the somatostatin analogue octreotide.

Acromegaly and hyperprolactinemia have been described in association with polyostotic fibrous dysplasia; the pathogenetic mechanisms involved in the development of the endocrinopathies is unknown. We report a 26-year-old man with polyostotic fibrous dysplasia and hypersecretion of GH and PRL. Plasma GH, PRL, and insulin-like growth factor-I (IGF-I) were elevated. Glucose-non-suppressible plasma GH concentrations, GH responsiveness to TRH and GHRH, and GH suppression after a test-dose of somatostatin, octreotide, and bromocriptine were found. Plasma GHRH levels were within the normal range (< 25 ng/l). Computed tomography of the sella turcica and visual fields were normal. [111In-DTPA-D-Phe1]-octreotide scintigraphy were used to localize a possible tumor; no radioactivity was visualized at the site of the hypothalamus, the pituitary or elsewhere in the body but a considerable accumulation of radioactivity was found in the os frontalis. Therapy with octreotide by continuous sc infusion partially suppressed GH and IGF-I (and normalized PRL). The results suggest that hypersecretion of GH in our patient is not due to a GH-secreting pituitary tumor, eutopic or ectopic hypersecretion of GHRH or autonomous somatotroph function. The origin of the disease in this patient might be an abnormal hypothalamic regulation of somatotrophs and/or an alteration in the transmembrane signalling systems.