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1.
Sci Total Environ ; 637-638: 1550-1558, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29801248

RESUMO

Prescribed fires are used as a fuel reduction tool, but heat alter microsite conditions affecting the natural regeneration of Mediterranean pine forests. Our study tested the hypothesis that implementing prescription before or after pine seed release may influence the composition of tree communities by changing the regeneration patterns of Pinus pinaster Aiton across a climatic gradient in the eastern Iberian Peninsula. We ran a seed-sowing experiment to analyse the recruitment patterns of this pine species in prescribed-burned stands, in two different biogeographical seed provenances from wetter and drier areas than the local seeding site. Survival of seedlings was through one year, until the end of the first drought and winter period, respectively. >5400 seeds were sown during the study distributed in sixty plots (30 burned, 30 unburned) per site and treatment, with 10 seeding units per plot. General linear models (GLMs) and ANOVA analyses indicated higher performance for the Drier seed provenance in burned areas, whereas a similar performance was recorded in the control area. Control areas showed higher germination and success rates for plant establishment throughout the study period. Total germination and survival after one year were slightly higher, respectively, at northern sites due to massive mortality during summer in the southern stands. At the burned sites, the mean germination time was significantly longer in those seeds sown before fire passage than those sown after fire. Total germination and successful establishment were significantly higher in the individuals sown before the passage of the fire than in those sown after fire. Most of the mortality occurred in summer for the southern stand, while winter was the most constraining period at the northern sites. The understanding of the dynamics in this species' establishment can help managers to perform a better management planning according to the species' ecology.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Incêndios , Florestas , Pinus/fisiologia , Queimaduras , Germinação , Plântula , Sementes/fisiologia , Árvores/fisiologia
2.
Plant Biol (Stuttg) ; 19(1): 46-52, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27094365

RESUMO

We analysed the effects of summer temperatures (28/14 °C) and/or desiccation (from 48% to 8% humidity) on imbibed Narcissus alcaracensis and N. longispathus seeds with an elongating embryo. In the N. alcaracensis seeds that overcame dormancy (embryo elongation = 27.14%), exposure to high temperatures induced secondary dormancy and reduced subsequent embryo growth. A further 3-month cold stratification (5 °C) was required to break secondary dormancy. Desiccation in early embryo growth stages (elongation = 11.42%) also reduced germination. Desiccation in the seeds in a more advanced growth stage (i.e. embryo elongation = 27.14%) induced secondary dormancy, which the further 3-month cold stratification did not overcome. When desiccation was preceded by high temperatures, seeds better overcame secondary dormancy (i.e. longer embryo elongation and seed germination). Treatments did not affect seed viability. In the N. longispathus seeds that overcame dormancy (embryo elongation = 59.21%), exposure to high temperatures induced secondary dormancy and they needed a further 1-month stratification at 15/4 °C + 2 months at 5 °C to reactivate the germination process. When embryo elongation was 42.10%, seed desiccation totally impeded subsequent germination. When embryo elongation reached 59.21%, desiccation induced secondary dormancy, which was not overcome by the above-described stratification treatment. When desiccation was preceded by high temperatures, seeds better overcame dormancy. Stress treatments killed 5-10% of seeds. This study suggests that the seeds of species with complex morphophysiological dormancy (MPD) levels are sensitive to desiccation in early embryo development stages, as opposed to the seeds of species with deep simple epicotyl MPD, which better tolerate water stress.


Assuntos
Narcissus/fisiologia , Dormência de Plantas , Sementes/fisiologia , Temperatura Baixa , Dessecação , Germinação , Temperatura Alta , Umidade , Estações do Ano , Temperatura
3.
Plant Biol (Stuttg) ; 17(4): 798-807, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25598169

RESUMO

The germination ecology of Sideritis serrata was investigated in order to improve ex-situ propagation techniques and management of their habitat. Specifically, we analysed: (i) influence of temperature, light conditions and seed age on germination patterns; (ii) phenology of germination; (iii) germinative response of buried seeds to seasonal temperature changes; (iv) temperature requirements for induction and breaking of secondary dormancy; (v) ability to form persistent soil seed banks; and (vi) seed bank dynamics. Freshly matured seeds showed conditional physiological dormancy, germinating at low and cool temperatures but not at high ones (28/14 and 32/18 °C). Germination ability increased with time of dry storage, suggesting the existence of non-deep physiological dormancy. Under unheated shade-house conditions, germination was concentrated in the first autumn. S. serrata seeds buried and exposed to natural seasonal temperature variations in the shade-house, exhibited an annual conditional dormancy/non-dormancy cycle, coming out of conditional dormancy in summer and re-entering it in winter. Non-dormant seeds were clearly induced into dormancy when stratified at 5 or 15/4 °C for 8 weeks. Dormant seeds, stratified at 28/14 or 32/18 °C for 16 weeks, became non-dormant if they were subsequently incubated over a temperature range from 15/4 to 32/18 °C. S. serrata is able to form small persistent soil seed banks. The maximum seed life span in the soil was 4 years, decreasing with burial depth. This is the second report of an annual conditional dormancy/non-dormancy cycle in seeds of shrub species.


Assuntos
Germinação/fisiologia , Dormência de Plantas/fisiologia , Sideritis/fisiologia , Ecologia , Ecossistema , Estações do Ano , Sementes/fisiologia , Solo , Temperatura
4.
Rev Esp Anestesiol Reanim ; 57(2): 79-85, 2010 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-20336998

RESUMO

OBJECTIVE: To analyze clinical records of cardiac surgery patients in an attempt to identify factors associated with mortality in the postoperative critical care units of the public health service hospitals in the Community of Valencia, Spain, in 2007. METHODS: Retrospective study of cases from January 1, 2007 to December 31, 2007. The charts of all patients who underwent cardiac surgery with or without extracorporeal circulation were reviewed. A data collection protocol was followed to obtain information on age, sex, body mass index (BMI), presurgical risk factors, type of surgery, duration of extracorporeal circulation, duration of ischemia, cause of death, and length of stay in the postoperative critical care unit. RESULTS: The study population consisted of 2113 patients at 5 public hospitals; 124 patients (70 men, 54 women) died. The mean (SD) age was 70 (9.43) years (range, 36-91 years). The mean BMI was 28.19 kg/m2 (maximum, 42 kg/m2). The mean Euroscore was 21.92 (maximum, 94.29). Hypertension was present as a preoperative risk factor in most patients (74.2%); dyslipidemia was present in 51.6%, diabetes mellitus in 38.7%, stroke in 73%, and renal failure in 2.4%. It was noteworthy was that the group who underwent coronary revascularization had the highest mortality rate (nearly 35% of the 124 patients). The next highest mortality rate (19.4%) was in patients who had combined procedures (valve repair or substitution plus coronary revascularization). Mortality was 18.5% in the group undergoing aortic valve surgery and 11.3% in those undergoing mitral valve surgery. The mean duration of extracorporeal circulation was 148.63 minutes. The mean duration of myocardial ischemia was 94.91 minutes. The most frequent cause of death was cardiogenic shock (54.8%). This was followed by distributive shock (29.8%) and hemorrhagic shock (8.9%). The mean length of stay in the postoperative critical care unit was 13.6 days. Overall mortality was 5.87%. CONCLUSIONS: The highest mortality rate among cardiac surgery patients in postoperative critical care units in hospitals in the Community of Valencia in 2007 was in patients who underwent coronary revascularization. The most prevalent preoperative risk factor was hypertension. Cardiogenic shock and distributive shock were the most frequent causes of death in these patients. A system for classifying risk is needed in order to predict mortality in critical care units and improve perioperative care.


Assuntos
Procedimentos Cirúrgicos Cardíacos/mortalidade , Mortalidade Hospitalar , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Comorbidade , Diabetes Mellitus/epidemiologia , Circulação Extracorpórea/efeitos adversos , Feminino , Humanos , Hipertensão/epidemiologia , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Estudos Retrospectivos , Fatores de Risco , Choque/etiologia , Choque/mortalidade , Espanha/epidemiologia
6.
Farm Hosp ; 30(2): 92-8, 2006.
Artigo em Espanhol | MEDLINE | ID: mdl-16796422

RESUMO

OBJECTIVE: To describe the use of rasburicase in adult patients with hematological neoplasias and to present a protocol for its administration jointly prepared by the hematology and the pharmacy departments based on the scientific evidence available. METHOD: Retrospective study that reviews treatments with rasburicase administered in a tertiary 800-bed hospital from July 2002 to May 2004 to adult patients with hematological neoplasias. The following data were collected: demographic and clinical data, daily dose of rasburicase and length of treatment, plasma levels of creatinine, potassium, phosphate, calcium, LDH, uric acid and white blood cell count daily and until 48 hours after administering the last dose of rasburicase. RESULTS: Rasburicase was administered to a total of 18 adult patients (mean age of 57 years; range 27-84; 11 men and 7 women). Prior to treatment, 16 patient had high levels of LDH, 12 patients had a blood count over 50,000 white blood cells/mm3, and 11 had serum levels of uric acid above 7 mg/dl. The dose of rasburicase administered was 0.2 mg/kg/day and the median length of treatment was 5 days (range 1-10). The levels of uric acid returned to normal values in all patients. Furthermore, an statistically significant decrease of creatinine levels was observed. The other biochemical parameters studied were duly controlled throughout the treatment. CONCLUSIONS: A high variability is observed in the use of rasburicase in our patients. The hematology and pharmacy services have been working jointly to prepare a consensus-based protocol according to which, depending on the patient s risk of developing TLS (tumoral lysis syndrome), standard prophylaxis is administered to low-risk patients (intravenous hydration, alopurinol and urine alcalinization) and rasburicase is administered initially for 1-3 days to patients with high risk of developing TLS.


Assuntos
Neoplasias Hematológicas/tratamento farmacológico , Hiperuricemia/tratamento farmacológico , Síndrome de Lise Tumoral/tratamento farmacológico , Urato Oxidase/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Feminino , Humanos , Hiperuricemia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Síndrome de Lise Tumoral/etiologia
7.
Presse Med ; 27(36): 1829-33, 1998 Nov 21.
Artigo em Francês | MEDLINE | ID: mdl-9856126

RESUMO

OBJECTIVE: Evidence-based medicine is a growing paradigm in health care. We conducted a prospective study to determine whether laparoscopic surgery is truly evidence-based in everyday practice. METHODS: A prospective regional survey was performed in 11 French hospitals (one university and 10 district hospitals) to ascertain how general laparoscopic surgery was conducted during the last 3 months of 1997. We also searched the electronic databases for original articles on laparoscopic procedures. The methodology of randomized trials was analyzed and procedures were classed by level of evidence. We assumed that an evidence-based procedure was which had been validated by well-designed randomized controlled or prospective trials giving homogeneous results. RESULTS: One half of the procedures performed had been evaluated by randomized controlled trials. Among the 428 laparoscopic procedures, 334 (78%) were found to be evidence-based (CI 74.1-81.9%). Twelve of the 18 indications for laparoscopy (67%) were evidence based (CI: 62.5%-71.5). There was no difference between university teaching hospitals and general district hospitals. CONCLUSION: Contrary to initial criticisms, the practice of laparoscopic surgery appears to be truly evidence-based in the majority of cases.


Assuntos
Medicina Baseada em Evidências/estatística & dados numéricos , Laparoscopia/estatística & dados numéricos , França , Humanos , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Ann Urol (Paris) ; 28(1): 24-7, 1994.
Artigo em Francês | MEDLINE | ID: mdl-8129371

RESUMO

Prostatic abscess is a rare complication of urinary tract infection, whose symptoms and signs are not often specific. Prostatic abscess can now be easily diagnosed by transrectal ultrasonography. The authors report six cases of prostatic abscess diagnosed by ultrasonography. These abscess were successfully drained by ultrasound-guided transrectal aspiration, which may constitute a useful solution, as the classical treatments to date consist of transurethral resection or rectotomy.


Assuntos
Abscesso/diagnóstico por imagem , Abscesso/terapia , Doenças Prostáticas/diagnóstico por imagem , Doenças Prostáticas/terapia , Punções , Ultrassonografia de Intervenção , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Doenças Prostáticas/microbiologia , Punções/instrumentação , Reto
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