RESUMEN
Although gall-inducing aphids, namely Pemphigus bursarius (L.) and P. phenax Börner et Blunck, are widely known as serious pests for their secondary hosts (lettuce and carrot, respectively), the physiological mechanism of their gall induction on Populus L. trees still requires a better understanding. In this study, we compared physiological parameters, i.e. H2 O2 , electrolyte leakage (EL ), MDA, APX and GPOD. Changes in physiological parameters were analysed in foliar tissues with galls and in the gall tissues themselves and compared to leaves without galls. Significantly higher H2 O2 levels were observed in P. phenax galls when compared to leaves with galls. In turn, the highest EL of cells and MDA content was in P. bursarius galls. Other samples had lower or similar oxidative stress marker levels to leaves without galls. APX and GPOD had similar activity profiles in galls of both aphid species. Their activity decreased significantly in gall tissues, where it was even ten-fold lower than in leaves without galls. Data generated in this study indicate that patterns of the physiological features, e.g. ROS accumulation and cell membrane integrity, of Populus leaves with galls and galls alone depends on the gall-inducing aphid species. Where decreased APX and GPOD activity, especially in gall tissues, indicated a reduction in the antioxidant potential of these neoformed structures.
Asunto(s)
Áfidos , Populus , Animales , Interacciones Huésped-Parásitos , Hojas de la Planta , Tumores de Planta , ÁrbolesRESUMEN
Tetraneura ulmi (L.), a member of Eriosomatinae subfamily, is one of the gall-forming aphids occurring on elms. Sap-sucking behaviour of founding mothers results in the formation of new plant organs. This study documents the changes in the content of plant biogenic amines (putrescine, cadaverine, spermidine, tryptamine, spermine and histamine) and key enzymes of their biosynthesis: lysine decarboxylase (LDC), tyrosine decarboxylase and ornithine decarboxylase (ODC) in galls and other parts of Siberian elm (Ulmus pumila L.) leaves during the galling process. The direction and intensity of these changes for particular amines and enzymes were dependent on the stage of gall development and part of the galling leaf. Generally, the amine content tended to increase in gall tissues during the 1st and 2nd period of the galling process and decreased in later phases. LDC and ODC activities were markedly enhanced, especially in gall tissues at the initial stage of the galling process.
Asunto(s)
Áfidos/fisiología , Ulmus/parasitología , Animales , Descarboxilasas de Aminoácido-L-Aromático/metabolismo , Aminas Biogénicas/metabolismo , Tumores de Planta/parasitología , Ulmus/metabolismoRESUMEN
Obesity is a condition associated with an increased risk of metabolic disorders, and in particular of type-2 diabetes (T2D). The treatment and prevention of obesity and associated metabolic disorders present great medical challenges. A major therapeutic goal in T2D is to control blood glucose levels, which can be achieved by pharmacological and nonpharmacological measures. The latter include increased physical activity and reduction of body fat mass by limiting dietary caloric content. Low-calorie diets (LCDs) involve a reduction in daily caloric intake by 25% to 30%. LCDs should be individualized depending on the patient's energy requirements, the severity of the obesity, and any accompanying diseases and treatments. Intermittent fasting (IF) involves caloric restriction for one or several days a week, or every day as the prolongation of the overnight fast. The results of recent clinical trials have shown that LCDs and intermittent fasting in patients with obesity (including those with coexisting T2D) can lead to a reduction in body fat mass and metabolic parameter improvements. These beneficial effects arise not only from the loss of body mass, but also from the activation of metabolic pathways specific to fasting conditions. However, the paucity of large-scale randomized controlled trials makes it difficult to prescribe LCDs or IF as reliable, routine methods for successful and stable weight loss.
Asunto(s)
Restricción Calórica , Diabetes Mellitus Tipo 2/dietoterapia , Ayuno , Obesidad/dietoterapia , Animales , Humanos , Aumento de PesoRESUMEN
The harmfulness of mealybugs resulting from sucking plant sap, secreting honeydew, and transmitting plant viruses can give them the status of serious pests. This study documents the influence of Pseudococcus maritimus (Ehrhorn) and Pseudococcus longispinus (Targioni Tozzetti) infestation on alterations in selected physiological parameters of Phalaenopsis x hybridum 'Innocence'. The condition of the cytoplasmic membranes was expressed as the value of thiobarbituric acid reactive substances. We have determined changes in the activities of catalase and guaiacol peroxidase and measured the following chlorophyll fluorescence parameters: maximum quantum yield of photosystem II (Fv/Fm), effective quantum yield (Y), photochemical quenching (qP), and nonphotochemical quenching (qN). The strongest physiological response of orchids was recorded in the initial period of mealybugs infestation. Prolonged insect feeding suppressed lipid peroxidation, peroxidase and catalase activity, as well as photosynthesis photochemistry. The pattern of changes was dependent on mealybug species. This indicated the complexity of the processes responsible for plant tolerance. Data generated in this study have provided a better understanding of the impact of two mealybug species infestation on Phalaenopsis and should be useful in developing pest management strategies.
Asunto(s)
Antibiosis , Hemípteros/fisiología , Herbivoria , Orchidaceae/fisiología , Animales , Femenino , NinfaRESUMEN
Cultivated orchids are the most abundantly attacked by polyphagous mealybugs. This study documented how different density of mealybug Pseudococcus longispinus (Targioni Tozzetti) infestation is associated with a response of antioxidative systems of Phalaenopsis × hybridum 'Innocence'. The degree of cell damage, estimated by electrolyte leakage measurement and the level of thiobarbituric acid reactive substances (TBARS), the content of pigments as well as the activity of antioxidative enzymes and proline level, as measurements of stress and stress compensation in moth orchid were examined. The highest electrolyte leakage (E L) value among samples from colonized plants was found in the orchids from series III (50 individuals/plant), whereas the lowest in the plants from series II (20 individuals/plant). The TBARS content reached the highest level at the lowest number of feeding insects (series I). Peroxidase activity toward guaiacol was significantly increased in series I (5 individuals/plant). The highest catalase activity was recorded in plants colonized by the highest number of scale insects (series III). Whereas, the highest value of proline was in series II. The content of individual photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids) in plant tissues did not vary significantly between control and colonized orchids. The results have not confirmed hypothesis that the increasing number of mealybugs occurring on plant enhanced plant physiological response. The degree of longtailed mealybug infestation on plants was positively correlated only with electrolyte leakage and catalase activity in leaf tissues.
Asunto(s)
Antioxidantes/metabolismo , Hemípteros/fisiología , Hibridación Genética/genética , Orchidaceae/genética , Orchidaceae/metabolismo , Orchidaceae/parasitología , Hojas de la Planta/metabolismo , Análisis de Varianza , Animales , Carotenoides/metabolismo , Catalasa/metabolismo , Membrana Celular/metabolismo , Clorofila/metabolismo , Clorofila A , Electrólitos/metabolismo , Peroxidasa/metabolismo , Densidad de Población , Prolina/metabolismo , Sustancias Reactivas al Ácido TiobarbitúricoRESUMEN
The aim of the study was to determine the percentage participation of lymphocytes CD3TCRgammadelta in peripheral blood of children with acute toxoplasmosis. The study compromised 30 children aged 2-14 years. Increase of the percentage of CD3TCR gammadelta cells was observed in the group of children with clinical symptoms of toxoplasmosis (mean value 5.7%) in relation to the comparative group (mean 4.4%), but in 12 children (40%) the mean value was 8.1%. Toxoplasma gondii infection produces a strong signal for activation of cells with gammadelta receptors. Examination of CD3TCRgammadelta cells may be helpful in the diagnosis of the acute phase of T. gondii infection.
Asunto(s)
Receptores de Antígenos de Linfocitos T gamma-delta/análisis , Subgrupos de Linfocitos T/inmunología , Toxoplasma/inmunología , Toxoplasmosis/diagnóstico , Toxoplasmosis/inmunología , Enfermedad Aguda , Adolescente , Animales , Niño , Preescolar , Femenino , Humanos , Masculino , Valores de ReferenciaRESUMEN
Clinical picture of congenital Toxoplasma gondii has been presented in 20 children. The infection was diagnosed in 18 children in the first and in 2 children in the sixth month of life. Clinical symptoms were observed in as many as 12 children. The most frequent symptoms were those concerning central nervous system, organ of vision in the form of hydrocephalus, spastic paresis, epilepsy, intracranial calcification, choroiditis, retinitis and vision impairment. The presented analysis indicates an urgent need of introduction of screening in pregnant women and infants and widespreading of prophylactic activity aiming at raising awareness of the existing threat of T. gondii infection.