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At least 1,027 records · Page 57Linked to original sources
PubMed2006

Differences in whole-body protein turnover between Iberian and Landrace pigs fed adequate or lysine-deficient diets.

The capacity for protein deposition in Iberian pigs is lower than in modern (e.g., Landrace) pig breeds, and the reasons for this remain unknown. The hypothesis tested in this work is that under similar nutritional and physiological conditions, whole-body protein turnover as well as the protein synthesis to protein deposition ratio differs between Iberian and Landrace breeds, resulting in dissimilar protein deposition rates. As a main objective, these variables were compared at different protein and Lys intakes in growing gilts. The study examined the effect of Lys deficiency because this is the prevalent condition during the fattening period of the Iberian pig in the Mediterranean forest, where the main feed source is oak acorn, which provides approximately one-third of the available Lys present in an ideal protein. Three diets were tested within each breed: 2 diets with an optimal essential AA pattern, containing 12 or 16% CP as-fed, or a Lys-deficient diet (35% of the recommended Lys content). This diet was supplied at 12% CP for the Iberian and 16% CP for the Landrace pigs, respectively. The contrasts made were breed x dietary protein concentration and breed x AA pattern (adequate vs. inadequate Lys content). Cumulative urinary (15)N excretion over 60 h after receiving an oral dose of [(15)N]-glycine was used to calculate N flux. Mean BW for Landrace and Iberian pigs were 25.8 +/- 0.55 kg and 30.8 +/- 0.74 kg, respectively. Protein deposition (g of N/(kg(0.75).d) was lower in the Iberian than in the Landrace gilts (4 to 16%; P = 0.002) and increased with dietary protein content. In contrast, protein synthesis and degradation [g of N/(kg(0.75).d)] were greater for the Landrace breed (16 to 18 and 23%, respectively, for the 2 dietary protein contents studied; P < 0.05), but no breed differences were detected in fractional protein synthesis and degradation rates. The ratio of protein synthesis:protein deposition (S/PD) did not change with dietary protein concentration or breed and achieved a mean value of 5.4. Irrespective of breed, Lys deficiency had a strong negative effect on N balance (P < 0.001) and increased the ratio of S/PD (P = 0.012). The greater rates of protein deposition, synthesis, and degradation in Landrace pigs than in Iberian pigs fed optimal AA-pattern diets were then attributed to differences in body protein mass. Consequently, these results validate the hypothesis of unequal synthesis and degradation, but not of unequal S/PD, between breeds.

Animal Feed↗
PubMedDate not supplied

The response of ectomycorrhizal fungal inoculum to long-term increases in nitrogen supply.

The inoculum of ectomycorrhizal (EM) fungi was examined in a 16 y long nitrogen fertilization experiment maintained in a temperate oak savanna. To measure EM fungal inoculum, bur oak seedlings were grown in three types of bioassays: (i) intact soil cores that measure inoculum such as spores, mycelia and mycorrhizal roots; (ii) resistant propagule bioassays that measure inoculum types resistant to soil drying; and (iii) previously mycorrhizal root bioassays that measure the ability of EM fungi to colonize new roots from mycorrhizal roots. Colonization of bur oak seedlings was characterized by morphotyping and where necessary by restriction analysis and internal transcribed spacer (ITS) sequencing. Fourteen morphotypes were found in intact soil core bioassays with species of Cortinarius, Cenococcum and Russula abundant. Five morphotypes were found in resistant propagule bioassays with Cenococcum, a thelephoroid morphotype and a Wilcoxina-like ascomycete abundant and frequent. In intact soil core bioassays total percent root colonization and number of morphotypes were not affected by N supply in 2000 and 2001. However the composition of EM fungi colonizing oak seedling roots was different with increased N supply such that Russula spp. (primarily Russula aff. amoenolens) were most abundant at the highest level of N supply. Dominant Russula spp. did not colonize any roots in resistant propagule bioassays but did colonize oak seedling roots from previously mycorrhizal roots. Results suggest that in this savanna N supply can influence the kinds of inoculum propagules present and thereby might affect the dynamics of ectomycorrhizal communities by differentially influencing reproductive and colonization strategies.

Biodiversity↗
PubMedDate not supplied

Growth and sporulation of Phytophthora ramorum in vitro in response to temperature and light.

Phytophthora ramorum, recently found in the US, is causing concern for hardwood forests and the nursery industry. In an effort to identify some of the environmental limitations to growth and sporulation we undertook a laboratory study of four US and three European (EU) isolates. On V8 media, isolates grew when incubated at 2-28 C and produced chlamydospores at 8-28 C. Sporangia were produced at all temperatures tested: 10-30 C for US isolates and 6-26 C for EU isolates. Optimal temperatures were 16-26 C for growth, 14-26 C for chlamydospore production and 16-22 C for sporangia production. US isolates grew less and produced fewer spores when exposed to increasing doses of near-UV radiation (50-300 microW/cm(2)) and visible radiation (250-1500 microW/cm(2)). EU isolates were exposed to 300 microW/cm(2) near-UV only, which significantly reduced growth of one of three isolates and had no significant effect on spore production. In our studies P. ramorum tolerated a broad range of temperature and light conditions, which suggests that it is capable of establishment in a wide geographic area.

Culture Media↗
PubMedDate not supplied

A re-evaluation of the Cortinarius scobinaceus and Cortinarius impolitus complex in the Mediterranean area.

We have conducted a taxonomic study of Cortinarius belleri, C. cistohelvelloides, C. impolitus and C. scobinaceus from material collected in Spain, France, Italy, Portugal and Morocco. Based on anatomy, morphology, ecology and distribution (geographical data) we recognize two species, C. impolitus and C. scobinaceus, and the new combination C. scobinaceus var. cistohelvelloides is made. Cortinarius belleri, C. cistohelvelloides, C. impolitus and C. scobinaceus have been typed, and a key for identification of these taxa is included.

Agaricales↗
PubMed2002

Developmentally and stress-induced small heat shock proteins in cork oak somatic embryos.

The timing and tissue localization of small heat shock proteins (sHSPs) during cork oak somatic embryo development was investigated under normal growing culture conditions and in response to stress. Western blot analyses using polyclonal antibodies raised against cork oak recombinant HSP17 showed a transient accumulation of class I sHSPs during somatic embryo maturation and germination. Moreover, the amount of protein increased at all stages of embryo development in response to exogenous stress. The developmentally accumulated proteins localized to early differentiating, but not the highly dividing, regions of the root and shoot apical meristems. By contrast, these highly dividing regions were strongly immunostained after heat stress. Findings support the hypothesis of a distinct control for developmentally and stress-induced accumulation of class I sHSPs. The possible role of sHSPs is discussed in relation to their tissue specific localization.

Adaptation, Physiological↗
PubMedDate not supplied

[Effects of kavergal on indices of lipid peroxidation and the condition of the antioxidant system in patients with rheumatic heart disease presenting with circulatory insufficiency].

132 patients with rheumatic heart disease presenting with circulatory insufficiency displayed increased LPO both in the blood plasma and red cells, decline in the antioxidant enzymes activity varying with the circulatory insufficiency functional class degree of severity. Basic therapy with making use of antiinflammatory drugs, cardiac glycosides, diuretics together with drugs endowed with an antiarrhythmic activity and nitroglycerin (where indicated) was found to have practically no effect on LPO level or activity of the antioxidant system. The use of the drug kavergal, 1 g three times daily (total daily dosage being 3 g) in the complex therapy, has been shown to significantly decrease hyperlipoperoxidation both in the blood plasma and red cells increasing the activity of enzymes of the antioxidant defence.

Adolescent↗
PubMed2000

[A study on the chemical components of essential oil of oak moss concrete by gas chromatography/mass spectrometry].

The essential oil of oak moss concrete was extracted by volatile oil content equipment. The chemical compositions and their relative contents were analyzed by GC and GC/MS. A Supelco-5 fused silica capillary column (30 m x 0.32 mm i.d.; 0.25 micron thickness) and a flame ionization detector (FID) were employed in GC analysis. The temperature program included temperature increase of 4 degrees C/min from 50 degrees C to 250 degrees C, and a 10 min isothermal period at 250 degrees C. Mass spectra were obtained by electron impact at 70 eV and a source temperature of 170 degrees C. Twenty-four volatile compounds of oak mass concrete were identified, which comprised more than 83% of volatile fraction. The major components were diethyl phthalate, alpha-terpineol, cedrane and linalool.

Acyclic Monoterpenes↗
PubMed2003

Stress-induced injuries and trace element concentrations in vascular leaf plants from an urban environment (Palermo, Italy).

We examined leaf injuries and measured trace element concentrations in vascular plants from an urban ecosystem with distinct stress valences (the city of Palermo), and compared them with samples of the same species from sites where the stress potential is lower. Urban pollution influences macro-, micro- and toxic element concentrations in leaves. Therefore these leaves can be used as markers of the chemical and biological effects of atmospheric pollution. We studied the trace element content in the leaves of two species, oleander and oak, both fairly tolerant plants and good indicators and bio-monitors of pollution contaminants. Samples were collected at various sites in different periods.

Cities↗
PubMed2003

Behavioural response to an unsuitable host plant in the gypsy moth (Lymantria dispar L.).

To assess local differentiation in host preference, a two-choice test was performed on first-instar gypsy moth larvae originating from an oak and locust-tree forest. More than 40 generations feeding on locust-tree leaves, rich in alkaloids, led to non-efficient discrimination of host leaves in larvae from a locust-tree forest. Possible causes of observed population differences are discussed in the present paper.

Acacia↗