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1.
Plant Biol (Stuttg) ; 20(5): 879-885, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29905395

RESUMO

Seed germination responsiveness to environmental cues is crucial for plant species living in changeable habitats and can vary among populations within the same species as a result of adaptation or modulation to local climates. Here, we investigate the germination response to environmental cues of Sisymbrella dentata (L.) O.E. Schulz, an annual endemic to Sicily living in Mediterranean Temporary Ponds (MTP), a vulnerable ecosystem. Germination of the only two known populations, Gurrida and Pantano, was assessed over a broad range of conditions to understand the role of temperatures, nitrate, hormones (abscisic acid - ABA and gibberellins - GA) and after-ripening in dormancy release in this species. Seed germination responsiveness varied between the two populations, with seeds from Gurrida germinating under a narrower range of conditions. Overall, this process in S. dentata consisted of testa and endosperm rupture as two sequential events, influenced by ABA and GA biosynthesis. Nitrate addition caused an earlier testa rupture, after-ripening broadened the thermal conditions that allow germination, and alternating temperatures significantly promoted germination of non-after-ripened seeds. Primary dormancy in S. dentata seeds likely allows this plant to form a persistent seed bank that is responsive to specific environmental cues characteristic of MTP habitats.


Assuntos
Brassicaceae/fisiologia , Germinação/fisiologia , Dormência de Plantas/fisiologia , Ecossistema , Nitratos/metabolismo , Reguladores de Crescimento de Plantas/fisiologia , Temperatura
2.
Plant Biol (Stuttg) ; 18 Suppl 1: 76-82, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25662792

RESUMO

Seed dormancy and germination characteristics may vary within species in response to several factors. Knowledge of such variation is crucial to understand plant evolution and adaptation to environmental changes. We examined the correlation of climate and population genetic differentiation (ISSR) with primary seed dormancy and germination behaviour in populations of the Atlantic-European soft-water pool specialist Hypericum elodes. Primary dormancy was measured by analysing seed germination response of fresh seeds and after various periods of cold stratification. Laboratory germination experiments revealed that the single most important factor for promoting germination was cold stratification prior to placing at the germination temperature. However, in agreement with their weaker primary dormancy, the seeds germinated well when fresh, and the benefit of cold stratification was more relaxed for the southern populations. Seeds of all populations demonstrated a near absolute requirement for a light and alternating temperature regime in order to germinate. The promoting effect of alternating temperatures was particularly effective at warm temperatures (mean 20 °C) but not at cool temperatures. Whilst seed germination requirements were similar among populations, the degree of primary dormancy varied considerably and was not associated with population genetic differentiation. Primary dormancy degree was instead associated with local climate: higher temperature in summer and rainfall in winter predicted weak and rapid loss of dormancy. These results suggest that seed maturation environment may play a substantial role in explaining the degree of dormancy in H. elodes, highlighting that physiological dormancy can be modulated by local climate.


Assuntos
Hypericum/fisiologia , Dormência de Plantas , Sementes/fisiologia , Adaptação Fisiológica , Clima , Temperatura Baixa , Genética Populacional , Germinação , Hypericum/genética , Hypericum/efeitos da radiação , Luz , Estações do Ano , Sementes/genética , Sementes/efeitos da radiação , Temperatura
3.
J Clin Oncol ; 12(11): 2309-16, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7964945

RESUMO

PURPOSE: The aim of the study was to investigate the role of squamous cell carcinoma antigen (SCC) in the management of patients with locally advanced cervical cancer treated by neoadjuvant chemotherapy and radical surgery. PATIENTS AND METHODS: SCC assay was performed with a radioimmunoassay kit in a series of 102 patients with locally advanced cervical cancer. The values of 2.5, 5, and 7 ng/mL were used to define SCC antigen positivity. The chi 2 and Fisher's exact test and the stepwise logistic regression were used to evaluate the distribution of marker values. Analysis of survival was performed using the Kaplan and Meier test and Cox multivariate regression analysis. RESULTS: SCC levels were elevated in 65%, 45%, and 32% of patients with primary tumors for cutoff values of 2.5, 5, and 7 ng/mL, respectively. SCC pretreatment levels correlated with stage, tumor volume and lymph node status. In the multivariate analysis, SCC expression proved to be an independent predictor of response to neoadjuvant chemotherapy. SCC posttreatment levels were strongly related to chemotherapy response. Moreover, the overall correlation between the clinical course of the disease and the variation of SCC levels was 83%. In patients with squamous cell tumors, survival was significantly longer in SCC-negative cases compared with SCC-positive cases (P = .04). Moreover, in patients undergoing surgery after response to neoadjuvant chemotherapy, low SCC values were associated with better prognosis (P = .02). In the multivariate analysis, parametrial involvement and SCC status proved to retain an independent prognostic value. CONCLUSION: Our data show that SCC assay may provide useful information to improve the prognostic characterization and disease monitoring of patients with locally advanced cervical cancer undergoing neoadjuvant chemotherapy.


Assuntos
Adenocarcinoma/imunologia , Antígenos de Neoplasias/sangue , Carcinoma de Células Escamosas/imunologia , Serpinas , Neoplasias do Colo do Útero/imunologia , Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Adenocarcinoma/terapia , Adulto , Idoso , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Prognóstico , Radioimunoensaio , Análise de Sobrevida , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/cirurgia
4.
Bone Marrow Transplant ; 14(6): 907-12, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7536071

RESUMO

Six patients with advanced ovarian carcinoma (OvCa), and six patients with stage II or III resectable breast cancer (BrCa) were treated with low-dose CY (LD-CY, 1500 mg/m2) and cisplatin (CDDP) 100 mg/m2 (OvCa) or epirubicin (EPR) 120 mg/m2 (BrCa) plus recombinant human G-CSF (rhG-CSF). Twelve days after chemotherapy, all patients underwent PBSC collection on an outpatient basis. Following the completion of the induction programme, all patients underwent high-dose chemotherapy (HDC) with carboplatin 1200 mg/m2, etoposide 900 mg/m2 and melphalan 100 mg/m2 with the reinfusion of PBSC. LD-CY plus rhG-CSF in combination with CDDP or EPR mobilised a very large number of PBSC. After a median of 13 days from chemotherapy, the concentration of PBSC in the peripheral blood was 40-fold higher than the same patient's baseline value. Each collection yielded a median of 10.8 x 10(4)/kg colony-forming unit granulocyte-macrophage. Severe myelosuppression occurred in all patients following HDC, but the infusion of PBSC produced a rapid and sustained haemopoietic recovery. After a median of 11 days from reinfusion, haemopoietic engraftment was complete and 80% of the patients had platelets > 100 x 10(9)/l and PMN > 1 x 10(9)/l within 14 days after reinfusion. We can conclude that the present therapeutic approach is an excellent option for mobilisation, collection and transplantation of PBSC during intensive dose adjuvant polychemotherapy of high-risk cancer.


Assuntos
Neoplasias da Mama/terapia , Cisplatino/administração & dosagem , Ciclofosfamida/administração & dosagem , Epirubicina/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/métodos , Neoplasias Ovarianas/terapia , Adulto , Terapia Combinada , Feminino , Hematopoese , Humanos , Pessoa de Meia-Idade , Transplante Autólogo
6.
J Clin Apher ; 12(2): 82-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9263115

RESUMO

In this report we analyzed sixty leukapheresis procedures on 35 patients with a new protocol for the Fresenius AS 104. Yields and efficiencies for MNC, CD 34+ cells, and CFU-GM indicate that the new protocol is able to collect large quantities of hemopoietic progenitors. Procedures were performed processing 8.69 +/- 2.8 liters of whole blood per apheresis and modifying 3 parameters: spillover-volume 7 ml, buffy-coat volume 11.5 ml, centrifuge speed 1,500 rpm; blood flow rate was 50 ml/min and the anticoagulant ratio was 1:12. No side effects were observed during apheresis procedures except for transient paresthesia episodes promptly resolved with the administration of calcium gluconate. Yields show a high capacity of the new program to collect on average MNC 17.28 +/- 10.85 x 10(9), CD 34+ 471 +/- 553.5 x 10(6) and CFU-GM 1278.7 +/- 1346.3 x 10(4) per procedure. Separator collection efficiency on average was 49.91 +/- 23.28% for MNC, 55.1 +/- 35.66% for CFU-GM, and 62.97 +/- 23.09% for CD 34+ cells. Particularly interesting are results for MNC yields and CD 34+ efficiency; these results make the new program advantageous or similar to the most progressive blood cell separators and capable to collect a sufficient number of progenitor cells for a graft with a mean of 1.80 +/- 0.98 procedures per patient.


Assuntos
Remoção de Componentes Sanguíneos/instrumentação , Células-Tronco Hematopoéticas , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Pessoa de Meia-Idade
7.
Br J Haematol ; 92(2): 287-94, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8602987

RESUMO

In order to investigate the effects of erythropoietin (EPO) plus granulocyte colony-stimulating factor (G-CSF) administration after peripheral blood progenitor cell transplantation (PBPCT) we performed a phase I/II study in patients with high-risk cancer. 15 consecutive patients were treated wit recombinant human G-CSF (rhG-CSF) at the dose of 5 micrograms/kg subcutaneously (s.c.) every 24 h until day + 12 and with recombinant human EPO (rhEPO) at the dose of 150 IU/kg s.c. every 48 h until day + 11 following PBPCT. Their haemopoietic recovery was compared to that obtained in eight historic and control patients who did not receive any cytokines after PBPCT. No side-effects were observed during EPO plus G-CSF treatment and the treatment was not discontinued in any of the patients before completion of the treatment plan. The administration of EPO plus G-CSF after PBPCT produced a significant increase in the rate of white blood cell (WBC) (P = 0.0005), polymorphonuclear leucocyte (PMN) (P = 0.0005) and platelet (PLT) (P = 0.0105) recovery compared to the control group. The acceleration in haemopoietic recovery observed in the EPO plus G-CSF-treated patients produced a significant reduction of the days with WBC < 1 x 10(9)/l (P = 0.0009), PMN < 0.2 x 10(9)/l (P = 0.0030) and PMN < 0.5 x 10(9)/l (P = 0.0006). EPO plus G-CSF-treated patients required a significantly lower number of single donor PLT transfusions (P = 0.0142) and did not experience neutropenic fever, but historic control patients experienced fever > 38 degrees C for a median period of 4 d (0-12) with a medial period of parenteral antibiotic administration of 7.5 d (0-17). The length of the hospital stay was significantly shorter in the study group than in the historic control group (P = 0.0264). In conclusion, we can confirm that EPO plus G-CSF treatment is feasible and potentiates the haemopoietic recovery after PBPCT, thus simplifying the clinical management of cancer patients who undergo high-dose chemotherapy.


Assuntos
Neoplasias da Mama/terapia , Eritropoetina/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Neoplasias Ovarianas/terapia , Adulto , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade
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