Species functional traits and abundance as drivers of multiplex ecological networks: first empirical quantification of inter-layer edge weights.

Many vertebrate species act as both plant pollinators and seed-dispersers, thus interconnecting these processes, particularly on islands. Ecological multilayer networks are a powerful tool to explore interdependencies between processes; however, quantifying the links between species engaging in different types of interactions (i.e. inter-layer edges) remains a great challenge. Here, we empirically measured inter-layer edge weights by quantifying the role of individually marked birds as both pollinators and seed-dispersers of Galápagos plant species over an entire year. Although most species (80%) engaged in both functions, we show that only a small proportion of individuals actually linked the two processes, highlighting the need to further consider intra-specific variability in individuals' functional roles. Furthermore, we found a high variation among species in linking both processes, i.e. some species contribute more than others to the modular organization of the multilayer network. Small and abundant species are particularly important for the cohesion of pollinator seed-dispersal networks, demonstrating the interplay between species traits and neutral processes structuring natural communities.

Contribution by vertebrates to seed dispersal effectiveness in the Galápagos Islands: a community-wide approach.

Seed dispersal and seedling recruitment are crucial phases in the life cycle of all spermatophyte plants. The net contribution of seed dispersers to plant establishment is known as seed dispersal effectiveness (SDE) and is defined as the product of a quantitative (number of seeds dispersed) and a qualitative (probability of recruitment) component. In Galápagos, we studied the direct contribution to SDE (number of seeds dispersed and effect on seedling emergence) provided by the five island groups of frugivores (giant tortoises, lizards, medium-sized passerine birds, small non-finch passerine birds, and finches) in the two main habitats in this archipelago: the lowland and the highland zones, and found 16 vertebrate species dispersing 58 plant species. Data on frequency of occurrence of seeds in droppings and number of seeds dispersed per unit area produced contrasting patterns of seed dispersal. Based on the former, giant tortoises and medium-sized passerines were the most important seed dispersers. However, based on the latter, small non-finch passerines were the most important dispersers, followed by finches and medium-sized passerines. The effect of disperser gut passage on seedling emergence varied greatly depending on both the disperser and the plant species. Although the contribution to SDE provided by different disperser guilds changed across plant species, medium-sized passerines (e.g., mockingbirds) provided a higher contribution to SDE than lava lizards in 10 out of 16 plant species analysed, whereas lava lizards provided a higher contribution to SDE than birds in five plant species. While both the quantitative and qualitative components addressed are important, our data suggests that the former is a better predictor of SDE in the Galápagos archipelago.

Sperm DNA fragmentation index does not correlate with the sperm or embryo aneuploidy rate in recurrent miscarriage or implantation failure patients.

BACKGROUND: The aneuploidy rate is higher in poor-quality sperm samples, which also have higher DNA fragmentation index values. The aim of this study was to assess the relationship between sperm DNA fragmentation in samples from infertile men belonging to couples with recurrent miscarriage or implantation failure and the aneuploidy rate in spermatozoa as well as in embryos from patients. METHODS: This prospective study evaluated DNA damage and the aneuploidy rate in fresh and processed (density gradient centrifugation) ejaculated sperm as well as the aneuploidy rate in biopsied embryos from fertility cycles. Fluorescence in situ hybridization was used for the aneuploidy analysis. Results were compared using linear regression and analysis of variance. RESULTS: A total of 154 embryos were evaluated from 38 patients undergoing PGD cycles; 35.2% of the embryos were chromosomally normal. Analysis of the same sperm samples showed an increased DNA fragmentation after sperm preparation in 76% of the patients. There was no correlation between DNA fragmentation and the aneuploidy rate in embryos or in fresh or processed sperm samples. CONCLUSIONS: Sperm DNA fragmentation is not related to chromosomal anomalies in embryos from patients with recurrent miscarriage or implantation failure. However, we cannot rule out the possibility that a relationship between DNA fragmentation and aneuploidy exists for other causes of infertility. Furthermore, the different methods used to evaluate DNA fragmentation may produce different results.

Reproductive success of the Canarian Echium simplex (Boraginaceae) mediated by vertebrates and insects.

Oceanic island ecosystems favour the appearance of novel interactions as a consequence of their depauperate and disharmonic flora and fauna. We investigated Echium simplex, endemic to the Anaga Biosphere Reserve in NE Tenerife, Canary Islands, belongs to the Canarian bird-flower element. Along two flowering seasons, we studied the breeding system of E. simplex, identified the floral visitors and compared the pollination effectiveness of different animal guilds (insects versus vertebrates) by means of selective exclosures. E. simplex is self-compatible but selfing significantly reduced fruit set. The flowers were visited by five bird species (mostly Phylloscopus canariensis and Serinus canarius, but also Cyanistes teneriffae, Sylvia atricapilla and Sylvia melanocephala), a lizard species (Gallotia galloti) and over a hundred insect species (mainly hymenopterans and coleopterans). Flying insects increased fruit set whereas small flower dwellers (mostly beetles) decreased both fruit and seed set. Vertebrates had a negligible effect on reproductive success. We conclude that although the floral resources provided by E. simplex may be important to some vertebrate species, these do not appear to contribute to increase fitness of the plant, which was more dependent upon flying insects for fruit and seed set. We additionally found that plant reproductive structures are heavily damaged by feral goats, which threaten the maintenance of this Canarian endemic species.

Results of PAL feasibility test in primary health care facilities in four regions of Bolivia.

SETTING: Primary health care (PHC) centres in four Bolivian regions. OBJECTIVES: To test the feasibility and impact of training general practitioners (GPs) in standard case management of respiratory conditions in patients aged > or =5 years. DESIGN: Comparison of the results of two surveys: the baseline survey before training and the impact survey after training on standard guidelines on case management of respiratory conditions. RESULTS: A total of 78 GPs working in 65 health centres participated in both surveys. The baseline survey registered 1033 respiratory patients and the impact survey 1154. The patients were comparable in sex distribution, previous visits, duration of symptoms and clinical diagnoses. The differences were significant in age distribution, concomitant diseases and risk factors. As a result of training, referrals to a higher level decreased by 34.6% and the proportion of tuberculosis (TB) suspects identified increased by 30%. The number of drugs prescribed per patient decreased by 16.2%. The average cost of prescription of any drug per patient dropped by 32.3%. CONCLUSION: Training in the standard practical approach to lung health guidelines improved the quality and reduced the cost of treatment of respiratory diseases at PHC units. Training should be an integral part of a comprehensive managerial approach for the implementation of case management guidelines.

Intrahepatic hepatitis C virus replication is increased in patients with regular alcohol consumption.

AIMS: To assess clinical significance of liver hepatitis C virus RNA levels and their relationship with epidemiological, biochemical and histological factors. METHODS: A total of 50 patients (mean age 35.5+/-7 years) with biopsy-proven chronic hepatitis C infection were recruited. Risk factors were drug abuse (n=21), transfusion (n=16), other parental routes (n=8; surgery=3, tattooing=5), and idiopathic (n=5). Duration of infection was 16+/-9 years. All patients showed abnormal alanine aminotransferase levels and positive serum hepatitis C virus RNA. Hepatitis C virus genotype was assessed by Inno-Lipa. Liver biopsy was performed for histology and for hepatitis C virus RNA quantification by Amplicor-HCV-Monitor Daily alcohol consumption was recorded on two occasions by anamnesis. Inflammation grade was mild (n=31) or severe (n=19). Fibrosis was early stage (n=42) or advanced (n=8). RESULTS: Mean hepatitis C virus RNA levels were 9.4x10(5)+/-1.5x10(6) copies/microg of total RNA in liver tissue, and 9.1x10(5)+/-1.3x10(6) copies/ml in serum. Viral load in liver was positively correlated with that in serum (r=0.51, p<0.001) and there was a significant relationship between daily alcohol consumption and intrahepatic hepatitis C virus burden (r=0.53; p<0.001). Patients infected with genotype 3a showed lower intrahepatic hepatitis C virus load than patients infected with genotype 1b; albeit without reaching statistical significance (0.49x10(6)+/-0.89x10(6) vs 1.44x10(6)+/-1.9x10(6) copies/microg of total RNA; p=NS). No relationships were observed between liver viral burden and age, risk factor status, duration of infection, ferritin and alanine aminotransferase levels or with grading and staging. CONCLUSIONS: Hepatitis C virus load in serum is a mirror of intrahepatic hepatitis C virus levels. Chronic alcohol consumption enhances intrahepatic hepatitis C virus concentration.

[An evaluation of the blood culture in disseminated mycobacteriosis]. / Valoración del hemocultivo en la micobacteriosis diseminada.

The objective of this study was to evaluate the usefulness of blood culture in the diagnosis of disseminated mycobacteria (DMB). This prospective study included all blood cultures done for patients with fever and under suspicion of having DMB between January 1991 and July 1992. Fifty-seven blood samples from 16 patients were cultured; 14 (87.5%) patients were HIV positive and all were diagnosed as having DMB. The cultures were processed by lysis-centrifugation and identification of mycobacteria was by hybridization with a DNA probe. Mycobacterial growth was detected in 5 cultures (8.7%) from 4 patients (25%) (3 HIV positive). M. tuberculosis was isolated in 3 and M. avium in 1. Mean time until isolation was 46 days. In all cases mycobacteria were isolated in other samples before they were found in cultures: M. tuberculosis was isolated in 2 bronchial aspirates (BAS), 2 in liver tissue (L), 2 in spleen tissue (S), one in alveolar bronchial lavage, one in sputum, one in spinal fluid (SF) and one in urine. M. avium was isolated in sputum and ALB. The three patients in whom M. tuberculosis was found died 1.4 and 32 days after admission. In samples from the 12 DMB patients with negative cultures (11 HIV positive, 92%), M. tuberculosis was isolated in 100% of ganglion and S samples, 90% in urine, 69% in sputum, 67% in ABL and LB, 63% in BAS and 33% in SF. None of these patients died in hospital. We find blood culture to be of little use in the diagnosis of DMB. Analysis of other samples leads to faster diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

[Influence of pregnancy in chronic hepatitis C virus infection]. / Influencia del embarazo en la infección crónica por el virus C de la hepatitis.

BACKGROUND: There is scarce information about the influence of pregnancy in patients with chronic hepatitis C virus infection is little know. PATIENTS AND METHODS: 6,556 pregnant women were screened for anti-HCV (ELISA II). We determine ALT, HCV-RNA by PCR (Amplicor Roche) and HCV viraemia (Amplicor-HCV-Monitor Roche) in the third trimester of pregnancy and after 6 months of delivery. HBsAg, anti-HIV and HCV serotype (Murex 1-3) were also determined. STATISTICAL ANALYSIS: Fisher test, paired-t and U Mann Whitney. RESULTS: Anti-HCV was positive in 59 out of 6,556 (0.9%). Mean (SD) age: 27 (9) years (range, 18-40). Drug users: 34 (57%), post-transfusion: 10 (18%) and unknown: 15 (25%). HIV positive 11 (19%). Serotype 1, 30 (51%), setotype 3, 7 (20%), and nontypeable, 22 (37%). We studied HCV-RNA before and after delivery in 35 women, 8 out of 35 (23%) had HCV-RNA negative in both analysis. ALT was normal in 88% of women during pregnancy and in 42% after delivery. ALT levels in pregnancy were 32.6 (39.5) and in postpartum 64.5 (53.4) U/l (p < 0.005). 6 women were RNA-VHC negative during pregnancy and positive in postpartum. HCV viraemia during pregnancy and postpartum was 503 (1,203) and 1,014 (1,907) thousand copies/ml (p < 0.05). No relation was found among ALT or HCV viraemia with risk factors, serotype or coinfection with HIV. CONCLUSIONS: The prevalence of anti-HCV in pregnant women is 0.9%. ALT is usually normal in pregnancy. A quarter of women were HCV-RNA negative in pregnancy and positive after delivery. The viraemia was lower in pregnancy than after delivery, which is consistent with the fact of the low mother-to-infant HCV transmission rate.

[Determination of hepatitis B virus genotype and detection of lamivudine-resistance mutations]. / Determinación del genotipo del virus de la hepatitis B y detección de mutaciones de resistencia al tratamiento con lamivudina.

OBJECTIVES: To determine hepatitis B virus (HBV) genotypes in southern Seville (Spain) and investigate the development of lamivudine-resistance mutations by using a hybridization technique with specific probes and by comparing the results with those of the direct sequencing technique. To evaluate the temporal relationship between variations in the level of HBV-DNA and detection of mutant variants. To analyze the influence of several genotypes on the pattern of mutations developed and on values of viral load and alanine aminotransferase (ALT) after their development. PATIENTS AND METHOD: In 37 patients with chronic HBV infection, HBV genotype was determined using the LiPA technique. In 10 of these patients undergoing lamivudine treatment for a mean of 19.2 months, the development of lamivudine-resistant mutations was investigated. In these 10 patients, the LiPA technique was compared with direct sequencing. During lamivudine treatment, we determined HBV-DNA by polymerase chain reaction (PCR) and ALT every 3-6 months. RESULTS: The most frequent genotypes were D (45.9%) and A (18.9%); 2 patients were genotype B while 18.9% had mixed genotypes. Sequencing showed identical results except in one mixed genotype. Mutations were found in 60% of the cases. The results of sequencing were in agreement, except in the detection of mixed populations composed of mutants and wild-type (WT). Patients with genotype A showed the pattern M204I+WT in the first 12 months and those with genotype D showed the pattern L180M+M204V with or without WT at 18 months. In 5/6 cases, an increase of > 1 log10 in HBV-DNA was observed 3-8 months before the mutation was detected by LiPA. In patients with genotype B, levels of HBV-DNA and ALT after the development of mutations was lower than basal levels and was also lower than those in patients with genotypes A and D. CONCLUSIONS: The LiPA technique for determination of HBV genotype and detection of lamivudine-resistance mutations shows excellent correlation with the most complex sequencing technique. Genotype D predominates in southern Seville. During lamivudine treatment, an increase in the level of HBV-DNA detected by PCR predicts the development of mutations before these are demonstrated by LiPA.

[The pattern of the sensitivity of Aeromonas spp. that produce extraintestinal infections]. / Patrón de sensibilidad de las Aeromonas spp. productoras de infecciones extraintestinales.

We studied the sensibility to several antimicrobics of aeromonas strains isolated in extraintestinal infections during a period of five years, in order to establish which could be the best empirical therapy in these processes. Twenty-two strains of A. hydrophila were evaluated, was isolated (8 from hemocultures, 6 from wound exudate, 2 from abscess aspirate, 2 from peritoneal fluid and 1 from urine, pleural fluid, bile and catheter). The identification was made using the GNI card System (Vitek System) and other tests. The sensibility was assessed using the GNS-BH and GNS-BI card System (Vitek), which allows to know the clinical category and CMI value in microgram/ml. All the strains presented some resistance to antibiotics. 77.8% of the strains were resistant to more than one antibiotic and 64.9%, to more than two antibiotics. We detected 21.7% strains resistant to 4 drugs. The most frequent resistance association was ampicillin, cephoxitine, cephazoline, cephalotine, with or without amoxicillin and clavulanic acid. All the strains were sensible to cephamandol, cephuroxime, cephtriaxone, cephtazidime, cephotaxime, thicarciline, aztreonam, azlociline, mezlociline, piperaciline, gentamycin, amikacine, chloranphenicol and ciprofloxacine. All the strains were resistant to ampicillin; 60.9% of the strains were sensible to the association amoxicillin and clavulonic acid. In conclusion, the treatment of extraintestinal infections does not differs basically from the treatment of the infections caused by Gram-negative bacillus. There are a broad range of effective antibiotics: aminoglycosides (gentamycin, tobramycin, amikacine), piperacyline, cephalosporines (cephuroxime, cephotaxime, cephtazidime and cephtriaxone), chloranphenicol, penemas, monobactanes of fluorquinolone.

Habitat use and phenology of the large insular endemic grasshopper Acrostira euphorbiae (Orthoptera: Pamphagidae).

The habitat use and the phenology of the large grasshopper Acrostira euphorbiae García and Oromí endemic to La Palma (Canary Islands) are studied. This grasshopper is entirely dependent on the Canarian endemic shrub Euphorbia lamarckii both for food and to avoid predation. Adults stay on subapical branches during the day, probably to reduce the risk of predation, and climb up to the apex at night to feed. While females seem to ensure the genetic diversity of offspring by waiting for visits by different males, the latter have to move to guarantee their reproductive success. Monophagy in this species may be related to the year-round presence of tender shoots, and to the predator-repellent toxic latex found in the host plant. Unlike related species from continental areas, adults and nymphs of A. euphorbiae are present almost all year round, probably in adaptation to the particular climate of the islands. Nymphs are more abundant in winter, when Euphorbia leaves are most available. However, adults are more abundant than nymphs in spring, summer and autumn. Males develop more quickly than females, an apparent reproductive strategy based on achieving sexual maturity to coincide with females undergoing imaginal moulting. Matings start immediately after adult females emerge. Densities oscillated between 73 and 193 individuals ha(-1), which can be considered a low value compared with other continental pamphagid species.

Haga su diagnóstico / Make your diagnosis

El diagnóstico es Pitiriasis liquenoide crónica

Sellado marginal en restauraciones indirectas, cementadas con dos sistemas adhesivos diferentes / Marginal sealing in indirect restorations, cemented with two different adhesive systems

Propósito: El propósito de esta investigación fue realizar un estudio in vitro del sellado marginal de 80 incrustaciones de resina compuesta cementadas con resina compuesta fluida utilizando un sistema adhesivo autograbante (Go!, SDI, Australia) y un sistema adhesivo con grabado ácido total (Stae, SDI, Australia). Método: Las piezas dentarias restauradas fueron puestas en una estufa a 37ºC y 100 por ciento de humedad relativa durante 48 horas para simular las condiciones bucales. Luego fueron sometidas a termociclado, en una solución de azul de metileno al 1 por ciento. Posteriormente las muestras fueron cortadas en sentido vestíbulo lingual o palatino, para ser observadas bajo un microscopio óptico, para evaluar la interfase diente restauración midiendo los porcentajes de filtración para ambos grupos. Resultados: Los resultados fueron analizados estadísticamente mediante el t-test de Student obteniéndose diferencias significativas entre los dos grupos estudiados. Conclusión: Todos los cuerpos de prueba presentaron algún grado de filtración marginal, sin embargo el grupo que utilizó un sistema adhesivo autograbante demostró tener valores significativamente mayores de filtración que el grupo que utilizó el sistema convencional.

Aim: The purpose of this research was to study the marginal sealing in 80 composite resin inlay, bonded with flow composite resin using a Self-etch fluid (Go!, SDI, Australia) versus a total-etching system (Stae, SDI, Australia). Method: The samples were placed in an oven at 37ºC and 100 percent humidity for 48 hours, after which the samples were thermocycled in a methylene blue 1 percent solution. This cycle was repeated 80 times. The samples were cut transversally, the restorations were observed trough an optical microscope to calculate the percentage of filtration in relation to the total length of the cavity to the axial wall. Results: The results were statistically analyzed by Student t-test. And there were significant differences in the marginal leakage. The group that used a Self-etch adhesive system showed significantly higher marginal leakage values than the group that used the conventional system. Conclusion: All the samples showed some degree of marginal leakage, but the group using a self-etching adhesive system showed marginal leakage values significantly higher than the group using the conventional one.

Outcome of bilateral hip hemiarthroplasty for displaced fracture of the hip.

Our aim was to evaluate the outcome in patients with bilateral non-simultaneous hip fracture treated with hemiarthroplasty at our institution between 1997 and 2003. We looked for any important modification factor that could change the devastating functional and social results. Twenty-two patients with a mean age of 79 at the initial fracture and 82 at the subsequent fracture were evaluated; all were Garden grade III-IV. The second fracture happened a mean of 28 months after the first one. The outcome measurement was the incidence of hip pain, recovery of pre-injury level of ambulation and activities of daily living at a minimum follow-up of one year. Following the first hemiarthroplasty patients deteriorated in their walking capacity and other activities of daily life, and this happened to an even greater extent after the second operation. With respect to walking ability (measured in metres) we concluded that it improved if a modular hemiarthroplasty was used after both fractures (p<0.05) and that worse functional outcomes were observed when different kinds of hemiarthroplasties were used in the same patient.;

Haga su diagnóstico / Make your diagnosis

El diagóstico es Enfermedad de Darier.

Value of serological diagnosis in congenital syphilis. Report of nine cases.

The diagnosis of congenital syphilis is difficult since it depends mainly on the results of serological tests. The results of five serological tests (three specific and two non-specific) in nine neonates with congenital syphilis are compared with those obtained in three with passively acquired antibodies. It appeared that the serological diagnosis of congenital syphilis must be based on the finding of specific neonatal antibodies in cord serum, which give positive results to the fluorescent treponemal antibody absorption test for immunoglobulin M, together with high titres of total IgM and negative results to latex tests. The non-specific tests are useful for confirming the efficacy of treatment. The mean number of cases of congenital syphilis in Seville is 0.81/1000 live births.

Interaction of aminoglycosides and cephalosporins against Pseudomonas aeruginosa. Correlation between interaction index and killing curve.

Three multiresistant clinical isolates of Pseudomonas aeruginosa were evaluated, by the chequerboard and the killing curve methods, for in-vitro synergy between cephalosporins and aminoglycosides. The killing-curve method was standardized to give results comparable with those obtained with the chequerboard test (FIC index). This was achieved with combinations showing synergy by chequerboard (FIC less than or equal to 0.75) by using in the killing curves subinhibitory concentrations: half the MIC in single antibiotic assay and one eighth the MIC in the combinations. For combinations that showed indifference by chequerboard (FIC = 1) half the MIC was used for antibiotics alone and in combination. For the antagonistic combinations by chequerboard (FIC greater than 2) concentrations equal to the MIC were used with single antibiotics and combinations in the killing curve experiments. Prediction of killing curve results could then be obtained with the FIC index. The killing curve results could not be explained by pH changes or inactivation of the antibiotics.

Phylogenetic relationships of the Canary Islands endemic lizard genus Gallotia (Sauria: Lacertidae), inferred from mitochondrial DNA sequences.

Phylogenetic relationships among species and subspecies of the Canary Island endemic lizard genus Gallotia are inferred based on nucleotide sequences of fragments of 12S ribosomal RNA and cytochrome b mitochondrial genes. The four morphologically established species have also been recognized at the molecular level. Relative affinities among species follow an eastern-western geographic transect. The nearly extinct species Gallotia simonyi from the most western island of El Hierro is closely related to the common western species Gallotia galloti, the nearest branch to this pair is Gallotia stehlini from the central island of Gram Canaria, and finally, Gallotia atlantica from the two eastern and geologically oldest islands appears as the most distantly related species of the group. At the statistical level, four subspecies can be recognized in G. galloti, but only two in G. atlantica.

[Lower respiratory infections caused by beta hemolytic group A Streptococcus]. / Infecciones respiratorias bajas por Streptococcus betahemolítico grupo A.

Three patients with beta-hemolytic group A streptococcal pneumonia were described. We emphasize the opportunistic pathogenic ability of the microorganism in the lower respiratory tract, and we describe the possible pathogenic mechanisms as well as the more frequent symptoms and complications.