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1.
Proc Biol Sci ; 287(1930): 20200807, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32635870

RESUMO

Large brains are a defining feature of primates, as is a clear allometric trend between body mass and brain size. However, important questions on the macroevolution of brain shape in primates remain unanswered. Here we address two: (i), does the relationship between the brain size and its shape follow allometric trends and (ii), is this relationship consistent over evolutionary time? We employ three-dimensional geometric morphometrics and phylogenetic comparative methods to answer these questions, based on a large sample representing 151 species and most primate families. We found two distinct trends regarding the relationship between brain shape and brain size. Hominoidea and Cercopithecinae showed significant evolutionary allometry, whereas no allometric trends were discernible for Strepsirrhini, Colobinae or Platyrrhini. Furthermore, we found that in the taxa characterized by significant allometry, brain shape evolution accelerated, whereas for taxa in which such allometry was absent, the evolution of brain shape decelerated. We conclude that although primates in general are typically described as large-brained, strong allometric effects on brain shape are largely confined to the order's representatives that display more complex behavioural repertoires.


Assuntos
Evolução Biológica , Encéfalo , Primatas , Animais , Tamanho Corporal , Filogenia
2.
PLoS One ; 14(1): e0210101, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30682060

RESUMO

Recognizing evolutionary trends in phenotypic means and rates requires the application of phylogenetic comparative methods (PCMs). Most PCMs are unsuited to make full use of fossil information, which is a drawback, given the inclusion of such data improves, and in some cases even corrects, the proper understanding of trait evolution. Here we present a new computer application, written in R, that allows the simultaneous computation of temporal trends in phenotypic mean and evolutionary rate along a phylogeny, and to contrast such patterns among different clades within the tree. By using simulation experiments, we show the new implementation, names search.trend is as powerful as existing PCM tools in discerning macroevolutionary patterns in phenotypic means and rates, but differently from any other PCM allows comparing individual clades to each other, and provides rich information about trait evolution for all lineages in the tree.


Assuntos
Evolução Biológica , Biologia Computacional/métodos , Extinção Biológica , Fósseis , Filogenia , Algoritmos , Fenótipo , Software
3.
Sci Rep ; 8(1): 7340, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743608

RESUMO

Members of the hominins - namely the so-called 'australopiths' and the species of the genus Homo - are known to possess short and deep mandibles and relatively small incisors and canines. It is commonly assumed that this suite of traits evolved in early members of the clade in response to changing environmental conditions and increased consumption of though food items. With the emergence of Homo, the functional meaning of mandible shape variation is thought to have been weakened by technological advancements and (later) by the control over fire. In contrast to this expectation, we found that mandible shape evolution in hominins is exceptionally rapid as compared to any other primate clade, and that the direction and rate of shape change (from the ape ancestor) are no different between the australopiths and Homo. We deem several factors including the loss of honing complex, canine reduction, and the acquisition of different diets may have concurred in producing such surprisingly high evolutionary rates. This study reveals the evolution of mandibular shape in hominins has strong morpho-functional and ecological significance attached.


Assuntos
Hominidae/anatomia & histologia , Hominidae/fisiologia , Mandíbula/anatomia & histologia , Animais , Evolução Biológica , Fósseis , Humanos , Mandíbula/patologia
4.
Transl Med UniSa ; 17: 37-41, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30050879

RESUMO

In the last years, epigenetics and functional genomics methods to evaluate the genomic effects and mechanisms of mind-body therapies have increasingly grown. DNA microarray technology has been used to show the involvement of the stress response pathways both in the case of disease and stress and as an effect of mind-body therapies. In the present research, the DNA samples obtained from 20 individuals who experienced a mind-body therapeutic protocol (MBT-T), were analysed from the bio-molecular point of view by means of an epigenetic marker (MSAP molecular tool), in order to estimate the different status of methylation. The subjects were compared at 3 different times: prior to, 1 hour after, and 24 hours after the treatment. The molecular data were processed through different biostatistics approaches: the Bayesian statistics approach, in order to estimate the clustering membership of the subjects (Structure), and the statistical estimation of the DNA methylation level (MSAP statistical tool). The structure analysis revealed that the clusters and their membership changed among the three time points moving from higher heterogeneous distribution to higher homogeneous clusters. Before the treatment, the subjects' epigenetic profiles were heterogeneous; after the mind-body treatment we found that epigenetic profiles converged to homogeneous DNA methylation status. DNA epigenetic status of the subjects was affected by the MBT-T treatment.

5.
Transl Med UniSa ; 17: 40-44, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30083522

RESUMO

In the last years, epigenetics and functional genomics methods to evaluate the genomic effects and mechanisms of mind-body therapies have increasingly grown. DNA microarray technology has been used to show the involvement of the stress response pathways both in the case of disease and stress and as an effect of mind-body therapies. In the present research, the DNA samples obtained from 20 individuals who experienced a mind-body therapeutic protocol (MBT-T), were analysed from the bio-molecular point of view by means of an epigenetic marker (MSAP molecular tool), in order to estimate the different status of methylation. The subjects were compared at 3 different times: prior to, 1 hour after, and 24 hours after the treatment. The molecular data were processed through different biostatistics approaches: the Bayesian statistics approach, in order to estimate the clustering membership of the subjects (Structure), and the statistical estimation of the DNA methylation level (MSAP statistical tool). The structure analysis revealed that the clusters and their membership changed among the three time points moving from higher heterogeneous distribution to higher homogeneous clusters. Before the treatment, the subjects' epigenetic profiles were heterogeneous; after the mind-body treatment we found that epigenetic profiles converged to homogeneous DNA methylation status. DNA epigenetic status of the subjects was affected by the MBT-T treatment.

6.
Sci Rep ; 6: 30965, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27507121

RESUMO

Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are effective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time.


Assuntos
Extinção Biológica , Especiação Genética , Modelos Biológicos , Animais , Biodiversidade , Evolução Biológica , Bases de Dados Factuais , Fósseis , Cadeias de Markov , Paleontologia , Simpatria
7.
FEBS Lett ; 291(2): 169-72, 1991 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-1936258

RESUMO

The effects of lonidamine on membrane electrical properties of Ehrlich ascites tumor cells are investigated. Using a dielectric relaxation technique based on the Maxwell-Wagner effect and elaborated by a 'single-shell' fitting procedure, the data indicate that both membrane conductivity and membrane permittivity increase after treatment of these cells with lonidamine while the conductivity of the cytosol remains unchanged. Changes in membrane proteins and/or lipids are suggested which lead to altered membrane structure and/or function.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Ehrlich/patologia , Indazóis/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Animais , Carcinoma de Ehrlich/química , Carcinoma de Ehrlich/tratamento farmacológico , Transformação Celular Neoplásica/efeitos dos fármacos , Citosol/efeitos dos fármacos , Condutividade Elétrica/efeitos dos fármacos , Masculino , Camundongos , Suspensões , Células Tumorais Cultivadas
8.
Biochem Pharmacol ; 38(5): 743-51, 1989 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2522779

RESUMO

The effect of rhein on the oxygen consumption, oxidative phosphorylation, ATPase activity and redox state of electron carriers of rat liver mitochondria has been studied. Rhein inhibits ADP- and uncoupler-stimulated respiration on various NAD-linked substrates and succinate, but stimulates state 4 respiration of mitochondria respiring on succinate. Experiments on specific segments of the respiratory chain showed that rhein does not inhibit electron flow through cytochrome oxidase. Electron flow through site 2, the ubiquinone-cytochrome b-cytochrome c1 complex, was also unaffected by rhein, which failed to inhibit the oxidation of duroquinol. Rhein affects oxidative phosphorylation by inhibiting both electron transfer and ADP-driven H+ uptake. The inhibition of succinate oxidation by rhein was found to take place at a point between succinate and ubiquinone, perhaps at the level of succinic dehydrogenase. Spectroscopic evidence demonstrated that rhein induces a NAD(P)H oxidation in mitochondria respiring either on endogenous substrates or on glutamate + malate, and an inhibition of the cytochrome b reduction by succinate. These observations, together with other evidence, suggest that rhein inhibits electron transport in rat liver mitochondria at the dehydrogenase-coenzyme level, particularly when the electron carriers are in a relatively oxidized state and/or when the inner membrane-matrix compartment is in the condensed state.


Assuntos
Antraquinonas/farmacologia , Transporte de Elétrons/efeitos dos fármacos , Mitocôndrias/metabolismo , Adenosina Trifosfatases/análise , Animais , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Técnicas In Vitro , Masculino , NAD/metabolismo , Oxirredução , Fosforilação Oxidativa/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Succinatos/metabolismo , Ácido Succínico
9.
Biochem Pharmacol ; 40(2): 217-22, 1990 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-2375763

RESUMO

The effect of rhein, 4,5-dihydroxyanthraquinone-2-carboxylic acid, on oxygen consumption and the rate of aerobic and anaerobic lactate production by Ehrlich ascites tumor cells has been investigated. The rate of oxygen uptake decreases with the increase of rhein concentration. Rhein also inhibits aerobic and anaerobic glycolysis. The rate of aerobic lactate production decreases with the drug concentration and the maximal effect was observed at 0.100 mM. Anaerobic lactate production is also inhibited and the maximum effect is reached at 0.220 mM. The possibility that the lactate production decrease was secondary to an effect on mitochondrial ATPase was excluded on the basis of the data with DNP and oligomycin. Rhein reduces the intracellular level of lactate, pyruvate and glucose-6-phosphate. Glucose utilization and 2-deoxy-D-glucose uptake are decreased to the same extent as the inhibition of aerobic lactate production, whereas glucose phosphorylation is unaffected. It is, therefore, concluded that the inhibition of glycolysis of Ehrlich ascites tumor cells by rhein is caused by an impairment of glucose uptake.


Assuntos
Antraquinonas/farmacologia , Metabolismo Energético/efeitos dos fármacos , Glucose/metabolismo , 2,4-Dinitrofenol , Animais , Carcinoma de Ehrlich/metabolismo , Dinitrofenóis/farmacologia , Glicólise/efeitos dos fármacos , Lactatos/metabolismo , Ácido Láctico , Masculino , Camundongos , Oligomicinas/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Células Tumorais Cultivadas
10.
Biochem Pharmacol ; 40(5): 967-73, 1990 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-2390116

RESUMO

The action of rhein, 4,5-dihydroxyanthraquinone-2-carboxylic acid, on protein synthesis of neoplastic cells has been investigated. Rhein decreases amino acid incorporation in all cells tested. The inhibition of incorporation of labeled precursors into acid-insoluble material cannot be ascribed to an impairment of amino acid uptake, which is unaffected by the drug. Tests on cell-free system showed that rhein does not inhibit the TMV-mRNA directed in vitro protein synthesis, thus indicating that the protein machinery per se is not affected. The inhibition of protein brought about by the drug must be ascribed to an effect on the energy-yielding processes with a remarkable decrease in ATP content. The mechanism is similar to that of other metabolic inhibitors, but rhein, for its capability to inhibit both respiration and glycolysis, is effective at much lower concentrations.


Assuntos
Antraquinonas/farmacologia , NADH NADPH Oxirredutases/antagonistas & inibidores , Biossíntese de Proteínas , Células Tumorais Cultivadas/efeitos dos fármacos , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/metabolismo , Animais , Feminino , Leucina/metabolismo , Masculino , Camundongos , Coelhos , Ratos , Ratos Endogâmicos
11.
Biochem Pharmacol ; 46(2): 330-2, 1993 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-8347157

RESUMO

Lonidamine is an antispermatogenic and anticancer drug that is believed to act by inhibition of energy metabolism. In this study, the effects of Lonidamine on the concentration of intracellular free Ca2+ of several tumor cell lines were assessed because of the important role that cytosolic Ca2+ plays in cell viability and proliferation. The presence of 300 microM Lonidamine resulted in large elevations of cytosolic Ca2+ (> 100 nM) in AS-30D rat ascites hepatoma cells and in cultured EMT6 murine mammary adenocarcinoma cells but had little effect on cultured NCI-H345 human small cell lung cancer cells. The apparent EC50 for Lonidamine was approximately 175 microM. The source of elevated cytosolic Ca2+ was primarily intracellular stores, and the effects of Lonidamine on Ca2+ efflux from these stores did not appear to be due to an ionophoretic action of this compound or to a decline in the level of cellular ATP. These results indicate that the Ca2+ homeostasis of certain lines of tumor cells is specifically altered by Lonidamine at concentrations known to affect cell proliferation.


Assuntos
Antineoplásicos/farmacologia , Antiespermatogênicos/farmacologia , Cálcio/metabolismo , Indazóis/farmacologia , Animais , Sítios de Ligação , Linhagem Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Relação Dose-Resposta a Droga , Ácido Egtázico , Fura-2 , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Lipossomos , Ratos , Células Tumorais Cultivadas/efeitos dos fármacos , Regulação para Cima
12.
Oncol Res ; 5(9): 357-62, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8038456

RESUMO

The utilization of carbon from 14C-labeled glucose by adriamycin (ADM)-sensitive and -resistant LoVo human colon carcinoma cells has been investigated. The following summarizes the results: 1. Aerobic glycolysis is the main energy-yielding process in both cell lines, whereas only a small proportion of glucose carbon atoms are incorporated into CO2, lipids, nucleic acids, and supporting structures. 2. Basic alterations in glucose metabolism are associated with drug resistance in tumor cells. In fact, ADM-resistant LoVo cells show a significant increase in the oxidative pathway of glucose metabolism as well as in acetyl-CoA production. 3. In adriamycin-resistant LoVo cells, the amount of glucose carbon atoms metabolized through the pentose phosphate pathway is significantly higher than in adriamycin-sensitive cells. These findings confirm a modified glucose metabolism in cells with a resistant phenotype.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/embriologia , Doxorrubicina/farmacologia , Glucose/metabolismo , Ciclo do Ácido Cítrico/efeitos dos fármacos , Resistência a Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Glicólise/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Via de Pentose Fosfato/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos
13.
Oncol Res ; 5(1): 1-10, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8369571

RESUMO

The effect of hyperthermia and lonidamine, alone and in combination, on the clonogenic activity of a human glioma cell line was investigated. The time-temperature relationship of asynchronous, exponentially growing cells was defined in the range of 40-45 degrees C. All survival curves were exponential and an Arrhenius plot for heat killing was linear over the temperature range tested, with an activation energy of 192 Kcal/mol. The survival curve of lonidamine-treated cells was also exponential after an initial shoulder. The analysis of the interaction between lonidamine and hyperthermia, performed by the isobolar method, demonstrated an additivity of response so that the effectiveness of the combined treatment was the result of two independent effects. Lonidamine inhibits the neoplastic growth mainly through an ATP depletion, but the thermal killing was not mediated by the drug-induced changes in the energy status of the cell. The effectiveness of the combined treatment was strongly influenced by the schedule of administration. In fact, the sequence lonidamine-->hyperthermia made the cells less sensitive to heat so that the pre-established end-point, i.e. 30% survival, was never achieved whichever combination was used. This "drug-induced heat resistance" was not associated with the induction of heat shock proteins, but rather with modification of cell cycle. On the contrary, showing a purely additive effect, the sequence hyperthermia-->lonidamine allowed achievement of the pre-established cell killing (70%), with exposure times (1-2 hr) and with a temperature (42 degrees C) generally accepted as clinically achievable. Therefore, also considering its low systemic toxicity, lonidamine may be useful in reducing the side effects of hyperthermia.


Assuntos
Antineoplásicos/farmacologia , Glioma/terapia , Hipertermia Induzida , Indazóis/farmacologia , Terapia Combinada , Glioma/tratamento farmacológico , Temperatura Alta , Humanos , Células Tumorais Cultivadas
14.
Anticancer Res ; 9(3): 811-5, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2669622

RESUMO

Lonidamine (LND) is an antitumor drug which interferes selectively with the energy metabolism of neoplastic cell. Because of its physico-chemical properties, LND determination with conventional methods, i.e. high performance liquid chromatography and spectrofluorimetry, gives rise to several problems: LND is a lipotropic drug which becomes intimately associated with biological membranes so that it is impossible to extract all the drug bound, thus leading to an underestimation of the LND content in cells and tissues. These difficulties can be overcome by the immunoenzymatic method described here. The assay is simple, rapid, practical, highly sensitive (2-5 ng/ml) and particularly suitable for the analysis of multiple samples (twelve samples in triplicate for each plate). There is, moreover, a great improvement in data reproducibility.


Assuntos
Antineoplásicos/análise , Indazóis/análise , Pirazóis/análise , Animais , Técnicas Imunoenzimáticas , Indazóis/imunologia , Indazóis/farmacologia , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Coelhos , Ratos , Ratos Endogâmicos
15.
Anticancer Res ; 10(6): 1633-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2285235

RESUMO

The effect of Rhein (RH) and Lonidamine (LND) on the clonogenic activity of cultured human glioma cells has been evaluated. Both these drugs decrease the survival fraction, but their effect is strictly related to the duration of exposure. A brief exposure, i.e. 4 hours, even at the highest drug concentrations does not induce any significant decrease in the survival which, on the contrary, is strongly affected by 24 and 48 hours of exposure. The reason for this behaviour lies in the mechanism of action of these drugs which do not interfere with replicative processes, but selectively affect the energy metabolism of the neoplastic cell. The validity of currently employed screening tests to evaluate the antitumoral activity of non anti-mitotic drugs is also discussed.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Indazóis/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ensaios de Seleção de Medicamentos Antitumorais , Glioma , Humanos , Cinética , NADH NADPH Oxirredutases/antagonistas & inibidores
16.
Pediatr Med Chir ; 7(6): 869-77, 1985.
Artigo em Italiano | MEDLINE | ID: mdl-3915553

RESUMO

Clinical outcome, lab examinations, therapy and aetiological theories of Kawasaki disease are discussed. All cases diagnosed in Italy since 1977 to 1984 have been collected (64 patients). This review shows that the disease affected mainly children from 3 months of age to 4 year, with a male to female ratio of 1.5:1 and the outcome was quite always benign, a part from a single case that went to death, with an overall mortality of 1 out of 64. Two cases observed from the AA are extensively described. The outcome was benign and one case showed high level of IgE. We stress that even if the Kawasaki disease is occasionally seen in our country, the physician must know the major features not to oversee the diagnosis.


Assuntos
Síndrome de Linfonodos Mucocutâneos , Pré-Escolar , Diagnóstico Diferencial , Feminino , Febre/etiologia , Humanos , Lactente , Itália , Masculino , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Síndrome de Linfonodos Mucocutâneos/etiologia , Síndrome de Linfonodos Mucocutâneos/terapia
17.
Pediatr Med Chir ; 18(3): 263-7, 1996.
Artigo em Italiano | MEDLINE | ID: mdl-8966126

RESUMO

Because of specific laboratory tests are lacking, diagnosis of cow's milk allergy is always made on the basis of improvement after cow's milk protein withdrawal from diet and relapsed after challenge test. However personal and familial anamnesis, supported by few simple laboratory tests (peripheral blood and stool eosinophiles, hemoccult), are important tools for diagnosis. In this work we report the clinical findings of 68 children, suffered from cow's milk allergy, observed in the last 10 years. Children were divided into three groups on the basis of challenge response: Group 1 consisting of children with averse reaction occurred within the first hour after the administration of cow's milk protein (IgE-mediated reaction, 1st class as Gell-Coombs classification); Group 2 consisting of children with averse reaction occurred between 2nd and 12th hour (1st-3rd class as Gell-Coombs classification); Group 3 consisting of children with averse reaction occurred after 24 hours the administration of cow's milk proteins (4th class as Gell-Coombs classification). Auxological parameters show that while weight is widely involved, particularly in children of group 3, height is interested only in children with prolonged diarrhoea. Cow's milk protein withdrawal from diet determine a rapid normalization of weight increment rate, more evident in children over 25th centile. Height rise up normal values slowly without any differences between children below and over 25th centile. At the age of two years 57 children (83%) became tolerant to cow's milk proteins and after 5-year follow-up in 3 children (4.4%) only persisted cow's milk allergy. All these children presented the IgE-mediate clinical form.


Assuntos
Hipersensibilidade a Leite/etiologia , Proteínas do Leite/administração & dosagem , Estatura , Peso Corporal , Pré-Escolar , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Imunoglobulina E/sangue , Testes Imunológicos/métodos , Lactente , Masculino , Hipersensibilidade a Leite/diagnóstico , Estudos Prospectivos
18.
Pediatr Med Chir ; 18(6): 615-7, 1996.
Artigo em Italiano | MEDLINE | ID: mdl-9173412

RESUMO

The authors report a case of a child three years old, with severe malnutrition as complication of Ascaris lumbricoides infection. Intestinal nematodes infect many of the world's children and constitute a formidable public health problem. The infected children may suffer nutritional deficits, serious illness and occasionally death. Although infestation is uncommon in our country, it should be considered in children with low social life.


Assuntos
Ascaríase/complicações , Ascaris lumbricoides , Enteropatias Parasitárias/complicações , Distúrbios Nutricionais/etiologia , Doença Aguda , Animais , Ascaríase/diagnóstico , Pré-Escolar , Diagnóstico Diferencial , Humanos , Enteropatias Parasitárias/diagnóstico , Masculino , Distúrbios Nutricionais/diagnóstico
20.
Environ Pollut ; 157(7): 2108-17, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19285369

RESUMO

Three ex situ collections of poplar clones from natural populations of Populus alba and P. nigra growing in northern Italy were assessed for their genetic dissimilarity (GD) by means of amplified fragment length polymorphism (AFLP). The high GD evidenced within populations was exploited for screening 168 clones in a field trial on heavy metal-polluted soil. After one growth season, clonal differences in plant survival and growth were observed. On the basis of performance, six clones were singled out, and used to evaluate copper and zinc accumulation in different organs. Clonal differences in metal concentrations were most evident for leaves and stems; one clone of P. alba (AL35) had a distinctly higher concentration of both metals in the roots. Leaf polyamine (putrescine, spermidine, spermine) profiles correlated with tissue metal concentrations, depending on the clone, plant organ and metal. In particular, the high metal-accumulating clone AL35 exhibited a dramatically higher concentration of free and conjugated putrescine. Overall, the results indicate that, given the high GD of Populus even within populations, it is possible to identify genotypes best suited for soil clean-up, and useful also for investigating physiological markers associated with high metal accumulation/tolerance.


Assuntos
Células Clonais , Metais Pesados/toxicidade , Folhas de Planta/química , Poliaminas/análise , Populus/genética , Poluentes do Solo/toxicidade , Cobre/análise , Cobre/toxicidade , Ecologia/métodos , Itália , Metais Pesados/análise , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/química , Caules de Planta/química , Populus/efeitos dos fármacos , Populus/crescimento & desenvolvimento , Solo/análise , Poluentes do Solo/análise , Zinco/análise , Zinco/toxicidade
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