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1.
Environ Sci Pollut Res Int ; 22(9): 6570-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25716900

RESUMEN

Southern Tuscany (Italy) is characterized by extensive arsenic (As) anomalies, with concentrations of up to 2000 mg kg soil(-1). Samples from the location of Scarlino, containing about 200 mg kg(-1) of As, were used to study the influence of the inoculation of an arbuscular mycorrhizal (AM) fungus (Rhizophagus irregularis, previously known as Glomus intraradices) and of phosphorus (P) application, separately and in combination, on As speciation in the rhizosphere of Zea mays on plant growth and As accumulation. Also, P distribution in plant parts was investigated. Each treatment produced a moderate rise of As(III) in the rhizosphere, increased As(III) and lowered As(V) concentration in shoots. P treatment, alone or in combination with AM, augmented the plant biomass. The treatments did not affect total As concentration in the shoots (with all the values <1 mg kg(-1) dry weight), while in the roots it was lowered by P treatment alone. Such decrease was probably a consequence of the competition between P and As(V) for the same transport systems, interestingly nullified by the combination with AM treatment. P concentration was higher with AM only in both shoots and roots. Therefore, the obtained results can be extremely encouraging for maize cultivation on a marginal land, like the one studied.


Asunto(s)
Arsénico/toxicidad , Glomeromycota/crecimiento & desarrollo , Micorrizas/crecimiento & desarrollo , Fósforo/química , Contaminantes del Suelo/toxicidad , Zea mays/crecimiento & desarrollo , Arsénico/análisis , Biomasa , Italia , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Brotes de la Planta/crecimiento & desarrollo , Brotes de la Planta/metabolismo , Brotes de la Planta/microbiología , Suelo/química , Contaminantes del Suelo/análisis , Zea mays/metabolismo , Zea mays/microbiología
2.
Environ Pollut ; 193: 205-215, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25058419

RESUMEN

Intra-specific variability of root biomass production (RP) of six rooted macrophytes, i.e. Juncus effusus, Phragmites australis, Schoenoplectus lacustris, Typha latifolia, Phalaris arundinacea, and Iris pseudacorus grown from clones, in response to Cu exposure was investigated. Root biomass production varied widely for all these macrophytes in control conditions (0.08 µM) according to the sampling site. Root biomass production of T. latifolia and I. pseudacorus in the 2.5-25 µM Cu range depended on the sampling location but not on the Cu dose in the growth medium. For P. australis, J. effusus, S. lacustris, and P. arundinacea, an intra-specific variability of RP depending on both the sampling location and the Cu-dose was evidenced. This intra-specific variability of RP depending on the sampling location and of Cu-tolerance for these last four species suggests that Cu constitutive tolerance for all rooted macrophytes is not a species-wide trait but it exhibits variability for some species.


Asunto(s)
Biomasa , Cobre/metabolismo , Cyperaceae/crecimiento & desarrollo , Magnoliopsida/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Poaceae/crecimiento & desarrollo , Cyperaceae/metabolismo , Magnoliopsida/metabolismo , Raíces de Plantas/metabolismo , Poaceae/metabolismo
3.
J Hazard Mater ; 227-228: 362-9, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-22673060

RESUMEN

This work investigates the element distribution in Silene paradoxa growing on the mine dump of Fenice Capanne (Tuscany, Italy). The accumulation of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in root apoplast and symplast and in shoot was assessed and compared to the levels of the same metals in the respective rizosphere soils, analyzing both the total and the phytoavailable fractions. Levels of As, Cu, Fe, Pb and Zn, were above toxicity thresholds in both soil and shoot samples. Inter- and intra-element correlations were analyzed in plant and soil using different statistical methods. Soil total and phytoavailable metal concentration were shown not to be dominant in determining metal accumulation by the plant, since no significant positive correlation was found between metal concentration in soils and plants. Moreover, results indicated that S. paradoxa was able to cope with the studied multi-metal contaminated soil excluding the elements from its tissues and preferentially accumulating them into the root compartment, thus suggesting this species as possible good candidate for phytostabilization purposes.


Asunto(s)
Arsénico/análisis , Metales Pesados/análisis , Raíces de Plantas/química , Brotes de la Planta/química , Silene , Contaminantes del Suelo/análisis , Monitoreo del Ambiente , Residuos Peligrosos
4.
Water Sci Technol ; 64(4): 826-31, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22097067

RESUMEN

In this study we investigated total and hexavalent chromium removal in an h-SSF constructed wetland (CW) planted with Phragmites australis and operating as post-treatment of effluent wastewater from an activated sludge plant serving the textile industrial district of Prato (Italy). Two measurement campaigns were carried out in 2006 and 2008-2010 in which more than 950 inlet and outlet samples were analyzed. When inlet and outlet concentrations were compared one to the other, the latter were found to be significantly lower than the former (p < 0.001); during the entire period of investigation, removal of hexavalent chromium equal to about 70% was achieved. Outlet concentrations ranged between values lower than the quantification limit (0.5 microg L(-1)) and 4.5 microg L(-1), and in all cases were therefore lower than the limit indicated for hexavalent chromium in the Italian regulation for water reuse (5 microg L(-1)). The comparison of the removal efficiencies achieved for hexavalent and trivalent chromium during the two campaigns suggested that the removal of the former can be sustained in the long term, while for the latter, the treatment efficiency is more sensitive to the age of the CW, being that it is it based on trivalent chromium retention in the reed bed.


Asunto(s)
Cromo/aislamiento & purificación , Residuos Industriales , Industria Textil , Contaminantes Químicos del Agua/aislamiento & purificación , Humedales , Límite de Detección , Control de Calidad
5.
J Hazard Mater ; 196: 66-72, 2011 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-21944702

RESUMEN

This work was planned for providing useful information about the possibility of using serpentine adapted plants for phytoextraction of cadmium, element scarcely represented in such metalliferous environment. To this aim, we investigated variation in cadmium tolerance, accumulation and translocation in three Alyssum plants with different phenotypes: Alyssum bertolonii, that is a serpentine endemic nickel hyperaccumulator, and two populations of Alyssum montanum, one adapted and one not adapted to serpentine soils. Plants were hydroponically cultivated in presence of increasing concentrations of CdSO(4) for two weeks. For the metal concentration used in the experiments, the three different Alyssum populations showed variation in cadmium tolerance, accumulation and content. The serpentine adapted population of A. montanum showed statistically higher cadmium tolerance and accumulation than A. bertolonii and the population of A. montanum not adapted to serpentine soil thus deserving to be investigated for phytoextraction purposes. Furthermore, as for the kinetic parameters of the cadmium uptake system, A. montanum serpentine population presented a low apparent K(m) value, suggesting a high affinity for this metal of its uptake system, whereas the V(max) values were not significantly different among the plants. Present data revealed metallicolous plants are also suitable for the phytoremediation of metals underrepresented in the environment of their initial origin. Nonetheless, field trials on real contaminated soils are essential.


Asunto(s)
Brassicaceae/crecimiento & desarrollo , Compuestos de Cadmio/aislamiento & purificación , Contaminantes del Suelo/aislamiento & purificación , Sulfatos/aislamiento & purificación , Asbestos Serpentinas/química , Biodegradación Ambiental , Brassicaceae/metabolismo , Compuestos de Cadmio/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Contaminantes del Suelo/metabolismo , Especificidad de la Especie , Sulfatos/metabolismo
7.
G Ital Med Lav Ergon ; 31(2): 149-53, 2009.
Artículo en Italiano | MEDLINE | ID: mdl-19827274

RESUMEN

INTRODUCTION: An integrated mental health surveillance program was developed by the department of occupational medicine at S. Chiara University Hospital in Pisa, Italy, in order to better assist and treat hospital staff suffering from psychiatric disorders in a preventive medical setting. MATERIAL AND METHODS: During the occupational medical surveillance of 4000 employees of S. Chiara Hospital in Pisa (Italy), 30 health care workers with psychiatric disorders were included in our program, which provided psycho-educational support and pharmacological treatment. Measures of effectiveness were: Clinical Global Impression (CGI scale) and a comparison between the average number of lost workdays due to mental illness before and after treatment. RESULTS: At the end of the observation period there was a decrease in the CGI severity score with a improved CGI score ranging from 1 to 2 and a reduction in absenteeism, from an annual average of 36.70 to 25.10 lost workdays. CONCLUSION: Our outcome measures data seem to indicate that a preventive medicine setting can offer effective psychiatric support that is better accepted and tolerated by health care workers and that this approach may reduce absenteeism.


Asunto(s)
Personal de Salud/estadística & datos numéricos , Trastornos Mentales/terapia , Vigilancia de la Población , Psicoterapia/métodos , Calidad de Vida , Encuestas y Cuestionarios , Absentismo , Adulto , Femenino , Estudios de Seguimiento , Humanos , Italia/epidemiología , Masculino , Trastornos Mentales/diagnóstico , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Servicios de Salud del Trabajador , Evaluación de Resultado en la Atención de Salud , Escalas de Valoración Psiquiátrica , Psicotrópicos/uso terapéutico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
8.
Bipolar Disord ; 7(4): 338-43, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16026486

RESUMEN

OBJECTIVE: To investigate the relationship between lifetime mood and psychotic spectrum features in patients with borderline personality disorder (BPD). METHOD: The study sample consisted of BPD patients with (n=39, BPD-M) or without (n=21, BPD-no M) lifetime mood disorders. The diagnostic assessment was conducted with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I). The diagnosis of BPD was made clinically and then confirmed by Gunderson's diagnostic interview for borderlines. Subjects were also administered the Structured Clinical Interview for Psychotic Spectrum (SCI-PSY) and the Mood Spectrum self-report questionnaire (MOODS-SR). RESULTS: BPD-M had significantly higher scores than BPD-no M on the 'lifetime' mood spectrum subdomains 'depressive mood' and 'depressive cognition'. The two groups did not differ on the scores of psychotic spectrum except for higher 'hypertrophic self-esteem' scores in BPD-no M. In BPD-no M both the depressive and the manic-hypomanic component of mood spectrum were significantly correlated with the 'delusion' subdomain of the psychotic spectrum. The depressive component was correlated with 'depersonalization/derealization' and the manic-hypomanic component was correlated with 'hypertrophic self-esteem'. In BPD-M, the manic-hypomanic component of mood spectrum was correlated with different subdomains of the psychotic spectrum: 'hypertrophic self-esteem', 'self-reference', 'interpretive attitude', 'anger/overreactivity, 'unusual and odd thoughts', 'illusions', 'delusions', 'hallucinations' and 'catatonia'. The depressive component of mood spectrum was 'uncorrelated' with the subdomains of the psychotic spectrum. CONCLUSIONS: Our data support the hypothesis that 'lifetime' manic-hypomanic mood dysregulations are correlated with psychotic spectrum features in borderline patients. The assessment of these spectrum features in borderline patients may be useful to inform treatment choices.


Asunto(s)
Trastorno de Personalidad Limítrofe/epidemiología , Trastornos del Humor/epidemiología , Trastornos Psicóticos/epidemiología , Adolescente , Adulto , Trastorno de Personalidad Limítrofe/diagnóstico , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Humor/diagnóstico , Trastornos de la Personalidad/diagnóstico , Trastornos de la Personalidad/epidemiología , Trastornos Psicóticos/diagnóstico
9.
Schizophr Res ; 75(2-3): 375-87, 2005 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15885528

RESUMEN

This study evaluates the validity and the reliability of a new instrument developed to assess the psychotic spectrum: the Structured Clinical Interview for the Psychotic Spectrum (SCI-PSY). The instrument is based on a spectrum model that emphasizes soft signs, low-grade symptoms, subthreshold syndromes, as well as temperamental and personality traits comprising the clinical and subsyndromal psychotic manifestations. The items of the interview include, in addition to a subset of the DSM-IV criteria for psychotic syndromes, a number of features derived from clinical experience and from a review of the phenomenological descriptions of psychoses. Study participants were enrolled at 11 Italian Departments of Psychiatry located at 9 sites and included 77 consecutive patients with schizophrenia or schizoaffective disorder, 66 with borderline personality disorder, 59 with psychotic mood disorders, 98 with non-psychotic mood disorders and 57 with panic disorder. A comparison group of 102 unselected controls was enrolled at the same sites. The SCI-PSY significantly discriminated subjects with any psychiatric diagnosis from controls and subjects with from those without psychotic disorders. The hypothesized structure of the instrument was confirmed empirically.


Asunto(s)
Entrevista Psicológica , Trastornos Psicóticos/diagnóstico , Adolescente , Adulto , Trastorno de Personalidad Limítrofe/diagnóstico , Trastorno de Personalidad Limítrofe/psicología , Escalas de Valoración Psiquiátrica Breve , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Humanos , Persona de Mediana Edad , Trastornos Psicóticos/psicología , Reproducibilidad de los Resultados , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Encuestas y Cuestionarios
10.
Dig Dis Sci ; 50(5): 847-52, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15906756

RESUMEN

Cytokines that regulate bone turnover (tumor necrosis factor-alpha, interleukin-6, etc.) may influence the pathogenesis of skeleton disorders, such as osteoporosis. Since Helicobacter pylori infection increases the systemic levels of inflammatory cytokines, we investigated the possibility that this infection increases the risk of developing osteoporosis and affects the bone metabolism in a group of male patients with osteoporosis. We examined 80 osteoporotic male patients and 160 controls for serum antibodies to H. pylori and the CagA protein and determined, in patients alone, the most important biochemical and instrumental parameters of the disease. Fifty-one patients (63.7%) and 107 controls (66.8%) were seropositive for H. pylori infection (nonsignificant); 30 infected patients (58.8%) and 43 infected controls (40.1%) were positive for anti-CagA antibodies (P = 0.028; OR = 2.13). Levels of estradiol in infected CagA-positive patients were significantly lower than in infected CagA-negative patients (28.5 [SD = 10.18] vs. 39.5 [SD = 14.50] pg/ml; P = 0.002) and uninfected patients (35.2 [SD = 12.7] pg/ml; P = 0.028). Levels of urinary cross-laps(a marker of bone resorption) were increased in patients infected by CagA-positive strains compared to patients infected by CagA-negative strains (282.9 [SD = 103.8] vs. 210.5 [SD = 150.1]microg/mmol; P = 0.048) and uninfected patients (204.3 [SD = 130.1] microg/mmol; P = 0.016). Differences among uninfected and infected patients, independent of CagA status, were observed for other markers of bone turnover, but they did not reach statistical significance. Infection by CagA-positive H. pylori strains is more prevalent in men with osteoporosis, who show reduced systemic levels of estrogens and increased bone turnover. H. pylori infection by strains expressing CagA may therefore be considered a risk factor for osteoporisis in men.


Asunto(s)
Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Osteoporosis/microbiología , Anciano , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/sangre , Proteínas Bacterianas/sangre , Remodelación Ósea/fisiología , Estudios de Casos y Controles , Infecciones por Helicobacter/sangre , Helicobacter pylori/inmunología , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/sangre , Factores de Riesgo , Estudios Seroepidemiológicos
11.
Dig Liver Dis ; 37(4): 232-9, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15788206

RESUMEN

PURPOSE: Phospholipase activity, one of Helicobacter pylori pathogenicity factors, has not been investigated enough, so far, although it may induce a remarkable damage to the gastric mucosa. In the present work, we have compared the whole phospholipase activity of H. pylori strains isolated from patients with gastric carcinoma with that of strains isolated from dyspeptic patients without gastric carcinoma. METHODS: We measured the phospholipase activity of one distinct H. pylori colony isolated from each of 10 patients with gastric carcinoma and 10 controls, dyspeptic patients without endoscopic and histological signs of gastric carcinoma. We also determined the phospholipase activity of 20 additional strains isolated from different areas of neoplastic and non-neoplastic tissue of two patients with gastric carcinoma, the cagA and vacA positive G27 and 328 wild strains and their respective vacA and cagA negative isogenic mutants. The whole phospholipase activity of strains was determined by measuring the release of (14)C-labeled palmitic acid from the radioactive l-3-phosphatidylcholine, 1,2-di[1-(14)C]palmiloyl substrate; results were expressed in pmol of palmitic acid per mg of protein. RESULTS: H. pylori strains isolated from patients with gastric carcinoma had levels of phospholipase activity significantly higher than those of strains isolated from controls (99.37 [S.D. 40.45] versus 34.46 [S.D. 16.46], P<0.001). In patients with gastric carcinoma, the mean phospholipase activity of strains isolated from neoplastic tissue was similar to that of strains isolated from non-neoplastic tissues (123.02 [S.D. 44.36] and 115.77 [S.D. 81.48], respectively. Interruption of cagA gene caused a ca. 20% reduction of phospholipase activity (36.38 versus 45.22 of the wild strain); that of vacA caused no reduction of phospholipase activity (26.53 and 25.37 of the wild strain). CONCLUSIONS: The infection by H. pylori strains that produce high levels of phospholipase may increase the risk of developing gastric carcinoma. We hypothesise that indirect products of phospholipase activity, such as prostaglandins, leukotrienes and lysophospholipids, may mediate carcinogenesis.


Asunto(s)
Infecciones por Helicobacter/microbiología , Helicobacter pylori/enzimología , Fosfolipasas/análisis , Neoplasias Gástricas/microbiología , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Biopsia , Enfermedad Crónica , Dispepsia/microbiología , Dispepsia/patología , Endoscopios Gastrointestinales , Gastritis/microbiología , Gastritis/patología , Tracto Gastrointestinal/microbiología , Tracto Gastrointestinal/patología , Infecciones por Helicobacter/patología , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Humanos , Mutación , Ácido Palmítico/metabolismo , Fosfatidilcolinas/metabolismo , Especificidad de la Especie , Neoplasias Gástricas/patología
12.
Microb Ecol ; 48(2): 209-17, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15546041

RESUMEN

Serpentine soils are characterized by high levels of heavy metals (Ni, Co, Cr), and low levels of important plant nutrients (P, Ca, N). Because of these inhospitable edaphic conditions, serpentine soils are typically home to a very specialized flora including endemic species as the nickel hyperaccumulator Alyssum bertolonii. Although much is known about the serpentine flora, few researches have investigated the bacterial communities of serpentine areas. In the present study bacterial communities were sampled at various distances from A. bertolonii roots in three different serpentine areas and their genetic diversity was assessed by terminal restriction fragment length polymorphism (T-RFLP) analysis. The obtained results indicated the occurrence of a high genetic diversity and heterogeneity of the bacterial communities present in the different serpentine areas. Moreover, TRFs (terminal restriction fragments) common to all the investigated A. bertolonii rhizosphere samples were found. A new cloning strategy was applied to 27 TRFs that were sequenced and taxonomically interpreted as mainly belonging to Gram-positive and alpha-Proteobacteria representatives. In particular, cloned TRFs which discriminated between rhizosphere and soil samples were mainly interpreted as belonging to Proteobacteria representatives.


Asunto(s)
Bacterias/genética , Brassicaceae/microbiología , Variación Genética , Raíces de Plantas/microbiología , Microbiología del Suelo , Secuencia de Bases , Clonación Molecular/métodos , Análisis por Conglomerados , Cartilla de ADN , Enzimas de Restricción del ADN/genética , ADN Ribosómico/genética , Italia , Metales Pesados/análisis , Datos de Secuencia Molecular , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Componente Principal , Análisis de Secuencia de ADN , Suelo/análisis
13.
Int J Methods Psychiatr Res ; 12(2): 105-15, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12830304

RESUMEN

This paper reports on the acceptability, reliability and validity of the Structured Clinical Interview for the Spectrum of Substance Use (SCI-SUBS), a new instrument exploring the interactive pathway between substance abuse and psychiatric disorders. Psychiatric outpatients with (n = 21) and without (n = 32) substance abuse comorbidity according to the DSM-IV, non-psychiatric subjects with opioid dependence (OD, n = 14) and normal controls (n = 33) were assessed with the SCI-SUBS. The presence or absence of psychiatric disorders was determined with the Structured Clinical Interview for DSM IV (SCID). The SCI-SUBS was well accepted by participants. The internal consistency of the domains was satisfactory (between 0.64 and 0.93). Domain scores of OD subjects were significantly higher than those of controls and of psychiatric patients without substance abuse. The cut-off point on the SCI-SUBS total score at which there was optimal discrimination between the presence and the absence of a DSM-IV diagnosis of substance abuse was 45. The pilot version of the SCI-SUBS has satisfactory internal consistency and construct validity.


Asunto(s)
Entrevista Psicológica/métodos , Trastornos Relacionados con Sustancias/diagnóstico , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Aceptación de la Atención de Salud , Proyectos Piloto , Reproducibilidad de los Resultados
14.
New Phytol ; 159(3): 691-699, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33873594

RESUMEN

• Molecular phylogeny based on ribosomal internal transcribed spacer (ITS) sequences was studied to investigate the phyletic relationships among some nickel (Ni)-hyperaccumulating and nonhyperaccumulating species of the genus Alyssum in relation to their geographic distribution and Ni-hyperaccumulating phenotype. • Thirty-seven samples belonging to 32 taxa were analysed by sequencing the polymerase chain reaction-amplified ITS region and performing neighbor joining, maximum parsimony and maximum likelihood phylogenetic analyses. • The ITS region in the sampled species varied from 221 to 307 bp of ITS1 and from 194 to 251 bp of ITS2. A total of 765 characters was used to infer the phylogeny and the average nucleotide variation detected was 15.15%. • Nickel-hyperaccumulation could have been lost or acquired independently more than once during the speciation of the genus. The geographical location of species could not be related to phylogenetic affinities.

15.
New Phytol ; 157(2): 349-356, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33873638

RESUMEN

• Chloroplast microsatellites (cpSSR) were used to analyze the patterns of genetic variation within and among populations of the serpentine endemic, Alyssum bertolonii . • Thirty-five different chloroplast haplotypes were identified in 90 plants sampled from nine populations originating from the four disjunct northern-Italian serpentine regions where the species is found. • High levels of genetic diversity were found within each of the populations sampled. Analysis of Molecular Variance (AMOVA) showed high degrees of differentiation among both different populations of the same serpentine region and different regions (Φ ST = 0.622, Φ CT = 0.252, respectively). • The results indicated that: each population was established by few founders and then subsequently differentiated the existing chloroplast haplotypes; each population is a distinct genetic entity; and populations within the same serpentine region are more related than populations from different regions.

16.
Mol Ecol ; 10(8): 1909-16, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11555235

RESUMEN

Eight populations of Silene paradoxa L. (Caryophyllaceae) growing in copper mine deposits, in serpentine outcrops or in uncontaminated soil in central Italy were studied. Genetic diversity was estimated using five polymorphic chloroplast microsatellite loci (cpSSR), identifying 27 different chloroplast haplotypes. The effective number of alleles, the haplotypic diversity and a stepwise mutational model-based parameter (DSH2) were computed. The effective number of alleles observed within populations from copper mine deposits was 20% that of the serpentine neighbouring populations, suggesting the occurrence of a founder effect. Moreover, 13 of the 27 different haplotypes scored were exclusive to only one population, indicating genetic isolation for all tolerant populations. Even the copper-tolerant populations appeared to have evolved independently. Finally, analysis of molecular variance (AMOVA) of the cpSSR markers gave statistical significance to the grouping of populations according to their geographical location. This study demonstrates that cpSSR markers could be a useful complementary tool to isoenzymes or random amplified polymorphic DNA markers for elucidating the pattern of genetic differentiation in heavy metal-tolerant populations.


Asunto(s)
ADN de Cloroplastos/genética , Variación Genética , Magnoliopsida/genética , Metales Pesados/metabolismo , Repeticiones de Microsatélite , Alelos , Cloroplastos/genética , Genes de Plantas , Haplotipos , Italia , Magnoliopsida/metabolismo
17.
Environ Microbiol ; 3(11): 691-8, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11846759

RESUMEN

In the present study, heterotrophic nickel-resistant bacteria were isolated and characterized from three different serpentine outcrops in central Italy populated by the nickel-hyperaccumulating plant Alyssum bertolonii. Bacteria were isolated from the rhizosphere of the plant and from soil portions at various distances from the plant. The proportion of nickel-resistant cfu was higher in proximity to the plant than in free soil. A total of 138 isolates was collected and grouped into 47 different operational taxonomic units (OTUs) by means of amplified ribosomal DNA restriction analysis (ARDRA) and into 25 heavy-metal resistant phenotypes. The phylogenetic position of strains belonging to 20 OTUs, representing more than the 70% of the total isolates, was determined by 16S rDNA sequencing. These analyses showed that the most represented genera in all three different outcrops were Pseudomonas and Streptomyces. Pseudomonas strains were found to be predominant in the plant rhizosphere, whereas Streptomyces strains were mainly present in the soil.


Asunto(s)
Brassicaceae/microbiología , Níquel/farmacología , Pseudomonas/fisiología , Microbiología del Suelo , Streptomyces/fisiología , Brassicaceae/metabolismo , Recuento de Colonia Microbiana , Farmacorresistencia Bacteriana , Italia , Metales/farmacología , Datos de Secuencia Molecular , Filogenia , Pseudomonas/clasificación , Pseudomonas/efectos de los fármacos , Pseudomonas/genética , ARN Ribosómico 16S/análisis , Streptomyces/clasificación , Streptomyces/efectos de los fármacos , Streptomyces/genética
18.
Mol Ecol ; 9(9): 1319-24, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10972771

RESUMEN

Metal-contaminated sites can occur naturally in serpentine outcrops or as consequence of anthropogenic activities, such as mining deposits, aerial fallout from smelters and industrial processes. Serpentine outcrops are characterized by high levels of nickel, cobalt and chromium and present a typical vegetation which includes endemisms and plants which also live in uncontaminated soils. These latter metal-tolerant populations provide the opportunity to investigate the first steps in the differentiation of plant populations under severe selection pressure and to select plants to be used in the phytoremediation of industrially contaminated soils. In this report eight populations of Silene paradoxa L. (Caryophyllaceae) growing in copper mine deposits, in serpentine outcrops or in noncontaminated soil in central Italy, were analysed using random amplified polymorphic DNA (RAPD) markers to investigate the pattern of genetic variation. The genetic diversity observed in populations at copper mine deposits was found to be at least as high as that of the neighbouring serpentine populations. Analysis of molecular variance (AMOVA) of the RAPD markers gave high statistical significance to the groupings of populations according: (i) with their geographical location; and (ii) with the metals present in the soil of origin (copper vs. nickel), indicating that RAPD markers detected a polymorphism related to the soil contamination by copper. Finally, two RAPD bands exclusive to copper-tolerant populations were identified.


Asunto(s)
Magnoliopsida/efectos de los fármacos , Magnoliopsida/genética , Metales Pesados/toxicidad , Secuencia de Bases , Cobre/toxicidad , Cartilla de ADN/genética , ADN de Plantas/genética , Variación Genética , Genética de Población , Italia , Filogenia , Técnica del ADN Polimorfo Amplificado Aleatorio , Selección Genética , Contaminantes del Suelo/toxicidad
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