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1.
Braz J Biol ; 83: e274991, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37909589

RESUMEN

The objective of this study was to evaluate the water status, photosynthetic pigments, and photochemical efficiency of mini watermelon plants under salt stress and phosphate fertilization. The experiment was conducted in pots under greenhouse conditions in Pombal, PB, Brazil. The experimental design used was randomized blocks in a 5 × 4 factorial scheme, with five levels of electrical conductivity of irrigation water - ECw (0.3, 1.3, 2.3, 3.3, and 4.3 dS m-1) and four doses of phosphorus (60, 80, 100, and 120% of the recommendation), with three replicates. The relative water content in the tissues decreased with the increase in ECw levels in all phosphorus doses, with decreases of 7.05, 7.81 and 8.83% per unit increase in ECw, in plants fertilized with 80, 100 and 120% P2O5. On the other hand, ECw levels increased electrolyte leakage, regardless of phosphorus doses of the recommendation. The synthesis of photosynthetic pigments and the quantum efficiency of photosystem II were inhibited by increasing water salinity from 0.3 dS m-1 in plants grown under phosphorus doses above 60% of the recommendation. Water salinity from 0.3 dS m-1 reduced chlorophyll b contents, initial, maximum, and variable fluorescence of mini watermelon plants, with a decrease of 11.86, 4.51, 4.53, and 4.54% per unit increment of ECw, respectively.


Asunto(s)
Citrullus , Fosfatos , Fotosíntesis , Aguas Salinas , Fósforo
2.
Braz J Biol ; 83: e274595, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37792747

RESUMEN

The objective of this study was to evaluate the salicylic acid applications in attenuating the harmful effects of saline nutrient solution on the physiology and growth of 'Gaúcho' melon cultivated in the NFT hydroponic system. The experiment was conducted in a greenhouse, in Pombal-PB, Brazil. The cultivation system used was the Nutrient Film Technique - NFT hydroponics. A completely randomized split-plot design was used, with the plot referring to four levels of salinity in the nutrient solution - ECns (2.1 control, 3.2, 4.3, and 5.4 dS m-1) and the sub-plot four concentrations of salicylic acid (SA) (0, 1.5, 3.0, and 4.5 mM), applied via foliar spray, with six replications. Nutrient solution of 4.3 and 5.4 dS m-1 electrical conductivity promotes higher maximum and variable fluorescence, respectively. The stomatal conductance, transpiration, stem diameter, main branch length, leaf dry mass, and stem dry mass of 'Gaúcho' melon plants decrease with the increase in salinity of the nutrient solution. Salicylic acid increases the initial fluorescence and the main branch length of 'Gaúcho' melon plants in hydroponic cultivation. Salicylic acid at a concentration of 1.5 to 4.5 mM did not attenuate the effects of salt stress on the internal CO2 concentration, CO2 assimilation rate, and root dry mass of 'Gaúcho' melon plants.


Asunto(s)
Dióxido de Carbono , Cucurbitaceae , Hidroponía , Ácido Salicílico/farmacología , Fluorescencia , Estrés Salino , Clorofila
3.
Phytomedicine ; 15(8): 630-4, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18164607

RESUMEN

The effects of alpha,beta-amyrin, a pentacyclic triterpene isolated from Protium heptaphylum was investigated on rat model of orofacial pain induced by formalin or capsaicin. Rats were pretreated with alpha,beta-amyrin (10, 30, and 100mg/kg, i.p.), morphine (5mg/kg, s.c.) or vehicle (3% Tween 80), before formalin (20 microl, 1.5%) or capsaicin (20 microl, 1.5 microg) injection into the right vibrissa. In vehicle-treated controls, formalin induced a biphasic nociceptive face-rubbing behavioral response with an early first phase (0-5 min) and a late second phase (10-20 min) appearance, whereas capsaicin produced an immediate face-rubbing (grooming) behavior that was maximal at 10-20 min. Treatment with alpha,beta-amyrin or morphine significantly inhibited the face-rubbing response in both test models. While morphine produced significant antinociception in both phases of formalin test, alpha,beta-amyrin inhibited only the second phase response, more prominently at 30 mg/kg, in a naloxone-sensitive manner. In contrast, alpha,beta-amyrin produced much greater antinociceptive effect at 100mg/kg in the capsaicin test, which was also naloxone-sensitive. These results provide first time evidence to show that alpha,beta-amyrin attenuates orofacial pain at least, in part, through a peripheral opioid mechanism but warrants further detailed study for its utility in painful orofacial pathologies.


Asunto(s)
Capsaicina/toxicidad , Dolor Facial/inducido químicamente , Dolor Facial/prevención & control , Formaldehído/toxicidad , Ácido Oleanólico/análogos & derivados , Analgésicos/administración & dosificación , Analgésicos/química , Analgésicos/uso terapéutico , Animales , Burseraceae/química , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Masculino , Estructura Molecular , Ácido Oleanólico/administración & dosificación , Ácido Oleanólico/química , Ácido Oleanólico/uso terapéutico , Fitoterapia , Ratas , Ratas Wistar
4.
J Urol ; 159(3): 875-7, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9474173

RESUMEN

PURPOSE: We evaluated the correlation of prostate specific antigen (PSA) and cardiac surgery in a group of patients with symptomatic benign prostatic hyperplasia operated on with or without extracorporeal cardiopulmonary circulation. MATERIALS AND METHODS: A total of 30 men 54 to 72 years old (mean age 62 years) undergoing cardiac surgery had PSA measured preoperatively and postoperatively. To provide the baseline PSA value a first serum sample was obtained before surgery, and PSA measurements were repeated 12 hours and 7 days postoperatively. Cardiac surgery was performed with extracorporeal cardiopulmonary circulation in 20 cases and without cardiopulmonary bypass in 10, constituted the control group. An 18F Foley catheter was left indwelling for the first 24 hours in both groups. RESULTS: In the study group there was a significant increase in PSA postoperatively (p = 0.01). However, in the control group the PSA was not statistically different before or after surgery (p = 0.16). These results indicate that there was a physiological relationship between the extracorporeal cardiopulmonary circulation and PSA. CONCLUSIONS: Although the etiology of this elevation is unknown, based on our data we conclude that extracorporeal cardiopulmonary circulation can cause an alteration in serum PSA unrelated to cardiac operation without extracorporeal bypass.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Circulación Extracorporea , Antígeno Prostático Específico/sangre , Hiperplasia Prostática/sangre , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
Ann Hum Genet ; 45(Pt 1): 1-4, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7316474

RESUMEN

C5 is polymorphic in Melanesians and related peoples. The polymorphism is demonstrated by isoelectric focusing and functional detection. Inheritance is autosomal and codominant. Preliminary linkage data suggest that C5 is not close to HLA.


Asunto(s)
Complemento C5/genética , Ligamiento Genético , Humanos , Focalización Isoeléctrica , Melanesia , Polimorfismo Genético
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