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1.
Mol Ecol ; 24(4): 726-41, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25580539

RESUMEN

Ecological and evolutionary studies largely assume that island populations display low levels of neutral genetic variation. However, this notion has only been formally tested in a few cases involving plant taxa, and the confounding effect of selection on genetic diversity (GD) estimates based on putatively neutral markers has typically been overlooked. Here, we generated nuclear microsatellite and plastid DNA sequence data in Periploca laevigata, a plant taxon with an island-mainland distribution area, to (i) investigate whether selection affects GD estimates of populations across contrasting habitats; and (ii) test the long-standing idea that island populations have lower GD than their mainland counterparts. Plastid data showed that colonization of the Canary Islands promoted strong lineage divergence within P. laevigata, which was accompanied by selective sweeps at several nuclear microsatellite loci. Inclusion of loci affected by strong divergent selection produced a significant downward bias in the GD estimates of the mainland lineage, but such underestimates were substantial (>14%) only when more than one loci under selection were included in the computations. When loci affected by selection were removed, we did not find evidence that insular Periploca populations have less GD than their mainland counterparts. The analysis of data obtained from a comprehensive literature survey reinforced this result, as overall comparisons of GD estimates between island and mainland populations were not significant across plant taxa (N = 66), with the only exception of island endemics with narrow distributions. This study suggests that identification and removal of markers potentially affected by selection should be routinely implemented in estimates of GD, particularly if different lineages are compared. Furthermore, it provides compelling evidence that the expectation of low GD cannot be generalized to island plant populations.


Asunto(s)
Variación Genética , Genética de Población , Islas , Periploca/genética , Selección Genética , Evolución Biológica , ADN de Cloroplastos/genética , ADN de Plantas/genética , Ecosistema , Flujo Genético , Sitios Genéticos , Repeticiones de Microsatélite , Datos de Secuencia Molecular , España
2.
Nat Prod Res ; 27(3): 255-65, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22439883

RESUMEN

The essential oil of roots, branches, leaves, flowers and fruits of Periploca laevigata Aiton subsp. angustifolia (Apocynaceae) from Lampedusa Island has been obtained by hydrodistillation and its composition analysed. The analyses allowed the identification and quantification of 86 volatile compounds. Branches showed the higher diversity with 57 compounds followed by fruits with 33, roots with 23, flowers with 16 and leaves with six compounds, respectively. In the matrices examined three constituents, heneicosane, docosane and tricosane are in common, although with different percentages. At least the most abundant compounds found in the matrices have been reported to have several biological activities. 2-Hydroxy-4-methoxybenzaldehyde identified in the roots as the most abundant component (70.7%) and present with 8.3% in the branches is a potent tyrosinase inhibitor present in several African medicinal plants, and thus being used as an ingredient in cosmetic and other medicinal products, primarily in relation to hyperpigmentation. Among the compounds identified, several play a role as semiochemicals for many animals, and 28 allomones, 43 pheromones, 21 kairomones have been identified. P. laevigata subsp. angustifolia in Lampedusa Island is host to a community of visitors, and the possible ecological role of the volatiles found is briefly discussed.


Asunto(s)
Apocynaceae/química , Aceites Volátiles/química , Flores/química , Frutas/química , Aceites Volátiles/análisis , Feromonas/química , Hojas de la Planta/química , Raíces de Plantas/química
3.
Biochem Genet ; 48(5-6): 524-37, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20390339

RESUMEN

Fusarium oxysporum f. melongenae is a major soil-borne pathogen of eggplant (Solanum melongena). ISSR and RAPD markers were used to characterize Fusarium oxysporum f. melongenae isolates collected from eggplant fields in southern Turkey. Those isolates were not pathogenic to tomato. Pathogens were identified by their morphology, and their identity was confirmed by PCR amplification using the specific primer PF02-3. The isolates were classified into groups on the basis of ISSR and RAPD fingerprints, which showed a level of genetic specificity and diversity not previously identified in Fusarium oxysporum f. melongenae, suggesting that genetic differences are related to the pathogen in the Mediterranean region. The primers selected to characterize Fusarium oxysporum f. melongenae may be used to determine genetic differences and pathogen virulence. This study is the first to characterize eggplant F. oxysporum species using ISSR and RAPD.


Asunto(s)
Fusarium/genética , Repeticiones de Minisatélite/genética , Técnica del ADN Polimorfo Amplificado Aleatorio , Solanum melongena/microbiología , Cartilla de ADN/genética , ADN de Hongos/genética , Fusarium/patogenicidad , Marcadores Genéticos/genética , Variación Genética
4.
Leuk Lymphoma ; 40(3-4): 295-303, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11426551

RESUMEN

We describe a single center experience of 41 consecutive patients with poor prognosis acute myeloid leukemia (AML) who received a single course of FLAG regimen consisting of Fludarabine 30 mg/m2/day plus Cytarabine 2 gr/m2/day (days 1-5) and G-CSF 5 mg/Kg/day (from day 0 to polymorphonuclear recovery) as salvage therapy. Eleven patients were primarily refractory to previous chemotherapy, 10 patients were in first relapse, 2 patients in second relapse and 7 patients in relapse after transplants. Eleven cases were defined as secondary AML (diagnosis of AML made after a preexisting diagnosis of myelodysplastic syndrome). The median age was 52.6 years (range 16-72); 29 patients were males and 12 females. Overall, 23 (56%) patients reached complete remission (CR), 3 patients died of infection (2) or hemorrhage (1) during induction, and 15 (36%) patients had resistant disease. The highest CR rates (80%) were obtained in relapsed cases; de novo and secondary AML registered 60% and 45% of CR rates, respectively. Patients achieving CR received a second FLAG course as consolidation and were submitted to an individualized program post-remission therapy, depending on the age and performance status. Hematological and non hematological toxicities were acceptable. In conclusion, our data confirm that FLAG is a an high effective treatment for poor prognosis AML and in young patients allows intensive post remissional therapy including allogeneic BMT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Mieloide/tratamiento farmacológico , Vidarabina/análogos & derivados , Enfermedad Aguda , Adolescente , Adulto , Factores de Edad , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Estudios de Cohortes , Citarabina/administración & dosificación , Citarabina/toxicidad , Supervivencia sin Enfermedad , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/toxicidad , Humanos , Infecciones/etiología , Infecciones/mortalidad , Leucemia Mieloide/complicaciones , Leucemia Mieloide/mortalidad , Masculino , Persona de Mediana Edad , Inducción de Remisión , Terapia Recuperativa , Factores Sexuales , Vidarabina/administración & dosificación , Vidarabina/toxicidad
5.
Leuk Lymphoma ; 37(1-2): 105-13, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10721774

RESUMEN

Twenty-nine cases of minimally differentiated acute myeloid leukemia or AML M0 identified among 441 AML diagnosed in the last 12 years are reported. In all cases, flow cytometric analysis using a large panel of monoclonal antibodies and cytogenetic and molecular studies (IgH, TcRbeta, BCR/ABL, AML1/ETO and CBFB-MYH11 rearrangements) were performed. Of the 29 patients, 27 were treated with intensive chemotherapy based on GIMEMA protocols. We noted a greater incidence of older (over 60 years) and male patients (52% and 65%, respectively). CD33, CD13, CD7 and TdT were expressed in 79.3%, 82.7%, 58.6% and 42.8% of cases, respectively. Antigenic MPO was present in 17 of 22 cases (77.3%). Most cases expressed CD34 (93.1%), HLA-DR (93.1%), CD117 (80%) and CD45RA (87%). CD45RO and CD90 were consistently negative. In all cases, we observed an up-expression of bcl-2 and a down-expression of CD95 with an inverse trend between the two markers (r -5253; p 0.03). Karyotypic abnormalities were demonstrated in 53.6% of cases. Of these, 6 involved chromosomes 5, 7 and 8, t(9;22), confirmed by the BCR/ABL transcript, was detected in one case. Rearrangements of the TcRbeta and IgH chains were observed in 3 and 2 cases, respectively. No AML1/ETO and CBFB-MYH11 transcripts were found. Twelve out of 27 patients (44%) achieved a complete remission (CR) (in 2 cases after rescue therapy). Seven early (range 1-9 months) and one late (32 months) relapses were observed. Five patients are alive, but only the 4 who underwent bone marrow transplantation are in persistent first CR. In conclusion, AML M0 is a subtype of AML antigenically well detectable, endowed with many adverse parameters (older age, TdT and CD34 expression, resistance to apoptosis, unfavorable cytogenetic abnormalities) and poor prognosis. A very aggressive consolidation treatment can be useful to improve the outcome.


Asunto(s)
Leucemia Mieloide/clasificación , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Femenino , Reordenamiento Génico , Humanos , Inmunofenotipificación , Cariotipificación , Leucemia Mieloide/genética , Leucemia Mieloide/inmunología , Leucemia Mieloide/terapia , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
6.
Haematologica ; 84(9): 844-52, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10477460

RESUMEN

BACKGROUND AND OBJECTIVE: Autologous transplantation is a better treatment for multiple myeloma (MM) than chemotherapy, but uncertainty remains about patient selection, optimal timing of autograft, conditioning regimen, need for a second autograft, and role of maintenance. To provide partial answers to these questions we assessed the results of autologous transplantation in a large cohort of patients whose data were reported to the GITMO registry. DESIGN AND METHODS: We retrospectively analyzed data from 290 patients with MM (M = 150; F = 140; median age 52 years, range 19-70; stage I = 34, stage II = 75, stage III = 167) reported to the GITMO. At the time of autograft, 20% were in CR, 66% in PR, while the remaining had non-responsive or progressive disease. Median time between diagnosis and transplant was 16 months (1-90). Seventy-two patients (26%) had been planned to receive a double autograft, but this was actually done in only 35 (12%). The conditioning was chemotherapy in 90%. Peripheral blood was the only source of stem cells in 94%, and purging was applied in 10% of cases. For statistical analysis of data, differences between patient subsets were analyzed using the chi-square test, while the Kaplan-Meier method was used to estimate event-free survival (EFS) and survival (OS) probabilities. The Cox model was used for multivariate analysis. RESULTS: Following the autograft, 116 patients (40%) were in CR, 144 (50%) in PR, 24 (8%) did not respond or progressed and 6 (2%) died before response evaluation. Transplant-related mortality occurred in 3%. At a median follow-up of 23 months, 223 (77%) patients are alive, 71 (24%) of them in CR, and 67 (23%) patients have died at a median time of 20 months (0-70). OS and EFS at 6 years are 47% and 28%, respectively, but the EFS curve shows no plateau. In multivariate analysis, age, beta2-microglobulin level and status at transplant emerged as significant prognostic factors for both OS and EFS, while time from diagnosis to transplant showed borderline significance. INTERPRETATION AND CONCLUSIONS: Based on the prognostic factors identified in multivariate analysis, we were able to assess the weight of a single prognostic factor or their combinations on transplant outcome. We also calculated the probability of OS and EFS by the number of factors at the time of autograft. Autologous transplantation is a safe and effective procedure, not only in sensitive patients, but also in resistant cases, provided they are <55 years of age and have low beta2-microglobulin. It should be applied early after the diagnosis of multiple myeloma, following the delivery of brief primary chemotherapy.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/estadística & datos numéricos , Mieloma Múltiple/terapia , Trasplante Autólogo/estadística & datos numéricos , Adulto , Factores de Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Estudios de Cohortes , Terapia Combinada , Progresión de la Enfermedad , Factores de Crecimiento de Célula Hematopoyética/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Factores Inmunológicos/uso terapéutico , Interferón-alfa/uso terapéutico , Italia/epidemiología , Tablas de Vida , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/mortalidad , Análisis Multivariante , Recurrencia Local de Neoplasia , Pronóstico , Modelos de Riesgos Proporcionales , Sistema de Registros , Inducción de Remisión , Estudios Retrospectivos , Terapia Recuperativa , Análisis de Supervivencia , Acondicionamiento Pretrasplante/mortalidad , Trasplante Autólogo/mortalidad , Resultado del Tratamiento , Microglobulina beta-2/análisis
7.
Haematologica ; 82(3): 354-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9234591

RESUMEN

The in vitro inhibitory effect of all-trans retinoic acid (ATRA) on myeloma cell growth may be synergistically potentiated by the activity of dexamethasone (DEX) and alpha-interferon (IFN). We treated 10 patients with advanced, refractory multiple myeloma (MM) using a combination of ATRA (100 mg p.o., once a day for two weeks every month), DEX (40 mg i.v., for 4 days every 4 weeks) and IFN (3 MU s.c., three times a week). Eight patients completed at least three months of treatment and were evaluable for response. Two of them showed a partial response which persists after 15 to 17 months. Three patients experienced a stable plateau phase of 4 to +11 months, with a significant improvement in the performance status and bone pain. Progressive disease was seen in the remaining three patients. We conclude that the association of ATRA, DEX and IFN warrants further consideration in MM patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mieloma Múltiple/terapia , Tretinoina/administración & dosificación , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Terapia Combinada , Depresión/inducido químicamente , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Progresión de la Enfermedad , Esquema de Medicación , Resistencia a Antineoplásicos , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Humanos , Factores Inmunológicos/efectos adversos , Factores Inmunológicos/uso terapéutico , Interferón-alfa/administración & dosificación , Interferón-alfa/efectos adversos , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Proyectos Piloto , Inducción de Remisión , Terapia Recuperativa , Estomatitis/inducido químicamente , Resultado del Tratamiento , Tretinoina/efectos adversos
9.
Bone Marrow Transplant ; 18(1): 225-7, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8832022

RESUMEN

We report a case of de novo plasma cell leukemia, resistant to standard VMD (vincristine, mitoxantrone, dexamethasone) and CVP (cyclophosphamide, vincristine and prednisone) protocols, treated with a chemotherapy intensification regimen (high-dose cyclophosphamide, modified EDAP, Dexa-BEAM) and peripheral blood stem cell transplantation, performed using fractionated total body irradiation and high dose melphalan. The patient is currently alive and well, in very good partial remission 12 months after transplant and 22 months after diagnosis, disclosing a significant proportion of bone marrow and peripheral blood CD3+, CD8+, CD57+, HLA-Dr+ large granular lymphocytes with cytotoxic activity against neoplastic plasma cells.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia de Células Plasmáticas/terapia , Recuento de Linfocitos , Subgrupos de Linfocitos T , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carmustina/administración & dosificación , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Citarabina/administración & dosificación , Dexametasona/administración & dosificación , Etopósido/administración & dosificación , Humanos , Leucemia de Células Plasmáticas/tratamiento farmacológico , Leucemia de Células Plasmáticas/patología , Masculino , Melfalán/administración & dosificación , Melfalán/uso terapéutico , Mitoxantrona/administración & dosificación , Prednisona/administración & dosificación , Inducción de Remisión , Acondicionamiento Pretrasplante , Vincristina/administración & dosificación , Irradiación Corporal Total
10.
Cytobios ; 86(347): 255-64, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-11536782

RESUMEN

The rapid growth rate of radish cells makes the hypocotyl particularly valuable in research on growth phenomena and gravitropism. An examination of mean data regarding the growth of aetiolated radish seedlings not subjected to gravitropic stimulation showed that there was an increase in the growth rate from day 3 to day 5. When the hypocotyl was placed horizontally all zones showed an increase in growth of the lower surface of the hypocotyl and generally a decrease in the growth rate in the upper surface. The upper apical part of the gravistimulated hypocotyl grew almost the same as controls. In some cases, in both 4- and 5-day-old seedlings, in the upper median part there was a lower growth rate than in controls. The zones of growth during the development of the hypocotyl were different. Analysis of curvature showed that the growth rate of the different zones was a function of their location in the hypocotyl and that the rate of curvature was different in various parts of the hypocotyl.


Asunto(s)
Brassicaceae/crecimiento & desarrollo , Gravitación , Gravitropismo/fisiología , Hipocótilo/crecimiento & desarrollo , Brassicaceae/fisiología , Hipocótilo/fisiología , Factores de Tiempo
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