Enhancing phytoremediative ability of Pisum sativum by EDTA application

The aim of our research was to demonstrate how the presence of EDTA affects resistance of pea plants to Pb and Pb-EDTA presence, and to show the effectivity of lead ions accumulation and translocation. It was determined that EDTA not only increased the amount of Pb taken up by plants but also Pb ion transport through the xylem and metal translocation from roots to stems and leaves. It can be seen in the presented research results that addition of the chelator with Pb limited metal phytotoxicity. We also demonstrated a significant effect of EDTA not only on Pb accumulation and metal transport to the aboveground parts but also on the profile and amount of thiol compounds: glutathione (GSH), homoglutathione (hGSH) or phytochelatins (PCs), synthesized by the plants. We observed a significant effect of the synthetic chelator on increasing the level of Pb accumulation in roots of plants treated with Pb including EDTA (0.5 and 1 mM). Pisum sativum plants treated only with 1 mM Pb(NO3)2 accumulated over 50 mg Pb x g(-1) dry wt during 4 days of cultivation. Whereas in roots of pea plants exposed to Pb+0.5 mM EDTA 35% more Pb was observed. When 1 mM EDTA was applied roots of pea accumulated over 67% more metal. The presence of EDTA also increased metal uptake and transport to the aboveground parts. In pea plants treated only with 1 mM lead nitrate less than 3 mg Pb x g(-1) dry wt was transported, whereas in P. sativum treated with Pb-EDTA doubled amount of Pb was observed in stems and leaves.     

Arsenic content in the femur head of the residents of southern and central Poland

Arsenic content was assayed in the samples of the femur head of the people living in southern and central Poland (Kraków, n=13; Silesian region, n=13; Łódź, n=12). The average age being 68.7±8.7 yr. Arsenic content in the femur head was determined applying the hydride generation atomic absorption spectrometry (HG-AAS) method after microwave mineralization. The average arsenic contents in the femur head of the residents of the Łódź, Kraków, and Silesian regions were 0.41 μg/g, 0.37 μg/g, and 0.18 μg/g, respectively. No correlation has been found between arsenic content in the femur head and the content of other metals. Neither the age nor sex of the people tested affected the arsenic content in the femur head.     

Effect of ulcerative colitis treatment on transforming growth factor beta(1) in plasma and rectal mucosa

The aim of this study was to evaluate the effect of active ulcerative colitis (UC) treatment on transforming growth factor beta(1) (TGF-beta(1)) concentration in plasma and rectal mucosa measured in 28 patients. The highest plasma values were observed in patients with the severe course of the disease (74.2+/-14.0 ng/ml), and they were significantly higher than in the group with mild one (43.7+/-5.6 ng/ml). Mean TGF-beta(1) measured in mucosal samples from patients with severe UC (563+/-146 pg/mg protein) doubled values from patients with mild UC (286+/-65 pg/mg protein). Plasma and mucosal TGF-beta(1) correlated significantly with disease activity index (DAI) and clinical activity index (CAI). Plasma TGF-beta(1) correlated additionally with scored endoscopic degree of mucosal injury. Treatment caused significant decrease of plasma and mucosal TGF-beta(1) concentrations. Patients who responded completely had higher baseline plasma and mucosal TGF-beta(1) that decreased significantly after the treatment. These results show that plasma and mucosal concentrations of transforming growth factor beta(1) are strongly associated with ulcerative colitis activity, and successful treatment of the disease results with decrease of their levels. More effective response to the treatment can be achieved in patients with higher baseline concentrations of TGF-beta(1).     

Recoverin is a zinc-binding protein

Recoverin is an N-myristoylated 23 kDa calcium-binding protein from retina, which modulates the Ca2+-sensitive deactivation of rhodopsin via Ca2+-dependent inhibition of rhodopsin kinase. It was shown by intrinsic and bis-ANS probe fluorescence, circular dichroism, and differential scanning calorimetry that myristoylated recombinant recoverin interacts specifically with zinc ions. Similar to the calcium binding, the binding of zinc to Ca2+-loaded recoverin additionally increases its alpha-helical content, hydrophobic surface area, and environmental mobility/polarity of its tryptophan residues. In contrast to the calcium binding, the binding of zinc decreases thermal stability of the Ca2+-loaded protein. Zn2+-titration of recoverin, traced by bis-ANS fluorescence, reveals binding of a single Zn2+ ion per protein molecule. It was shown that the double-mutant E85Q/E121Q with inactivated Ca2+-binding EF-hands 2 and 3 (Alekseev, A. M.; Shulga-Morskoy, S. V.; Zinchenko, D. V.; Shulga-Morskaya, S. A.; Suchkov, D. V.; Vaganova, S. A.; Senin, I. I.; Zargarov, A. A.; Lipkin, V. M.; Akhtar, M.; Philippov, P. P. FEBS Lett. 1998, 440, 116-118), which can be considered as an analogue of the apo-protein, binds Zn2+ ion as well. Apparent zinc equilibrium binding constants evaluated from spectrofluorimetric Zn2+-titrations of the protein are 1.4 x 10(5) M(-1) (dissociation constant 7.1 microM) for Ca2+-loaded wild-type recoverin and 3.3 x 10(4) M(-1) (dissociation constant 30 microM) for the E85Q/E121Q mutant (analogue of apo-recoverin). Study of the binding of wild-type recoverin to ROS membranes showed a zinc-dependent increase of its affinity for the membranes, without regard to calcium content, suggesting further solvation of a protein myristoyl group upon Zn2+ binding. Possible implications of these findings to the functioning of recoverin are discussed.     

Physiological cost of running while wearing spring-boots

The purpose of the study was to investigate the physiological cost of running in spring-boots compared with running in running shoes at different speeds. During testing, subjects (n = 7) completed running trials while wearing spring-boots and running shoes. Three speed conditions (2.23, 2.68, and 3.13 m.s(-1)) were completed per shoe condition (i.e., spring-boots and running shoes). Rate of oxygen consumption (Vo(2)), heart rate (HR), rating of perceived exertion (RPE), and stride frequency were recorded for each condition. Order of shoe conditions was balanced, with speeds tested continuously from slow to fast. There was no difference in Vo(2), HR, or RPE between shoe conditions across speeds (p > 0.05). Stride frequency was lower during running in spring-boots vs. running shoes at each speed (speed of spring-boots vs. running shoes for 2.23 m x s(-1): 69.9 +/- 2.9 strides x min(-1) vs. 75.6 +/- 3.5 strides x min(-1); for 2.68 m x s(-1): 71.3 +/- 5.2 strides x min(-1) vs. 79.4 +/- 5.0 strides x min(-1); for 3.13 m x s(-1): 73.6 +/- 7.3 strides x min(-1) vs. 83.1 +/- 8.2 strides x min(-1); p < 0.05). Despite the added mass to the lower extremity and change in stride frequency during running in spring-boots, the physiological cost of running was similar to that of running in running shoes. Exercising while running in spring-boots may provide less impact force with no change in running economy.     

Detection of substance P and its mRNA in human blast cells in childhood lymphoblastic leukaemia using immunocytochemistry and in situ hybridisation

The study focused on determining the expression of substance P (SP) in neoplastic cells of childhood acute lymphoblastic leukaemia (ALL) at the levels of its mRNA and the protein production. The study group comprised 44 children treated for ALL in the Department of Paediatric Haematology and Oncology, Karol Marcinkowski University of Medical Sciences in Poznań, in the years 1999-2001. Bone marrow smears were obtained by needle biopsy. Expression of SP was examined by immunocytochemistry with specific antibody against human SP and by in situ hybridisation with anti-mRNA 5'-biotinylated probe. The results of the study demonstrated that SP could be detected in the cytoplasm of lymphoblasts (mean percentage of 81.8% for immunocytochemical and 84.5% for in situ hybridisation technique) in leukaemias of the common and T-cell types. SP was absent from blasts in B-cell leukaemia and from normal haematopoietic, cells in children of the control group. The results show that lymphoblasts of common and T-cell origin acquire the capability to synthesise SP after their neoplastic transformation in childhood acute leukaemia. SP may be involved in auto- and paracrine mechanisms capable of inducing hyperplasia of the neoplastic cells.     

Glucagon response to exercise is critical for accelerated hepatic glutamine metabolism and nitrogen disposal

The aim of this study was to determine the role of glucagon in hepatic glutamine (Gln) metabolism during exercise. Sampling (artery, portal vein, and hepatic vein) and infusion (vena cava) catheters and flow probes (portal vein, hepatic artery) were implanted in anesthetized dogs. At least 16 days after surgery, an experiment, consisting of a 120-min equilibration period, a 30-min basal sampling period, and a 150-min exercise period, was performed in these animals. [5-(15)N]Gln was infused throughout experiments to measure gut and liver Gln kinetics and the incorporation of Gln amide nitrogen into urea. Somatostatin was infused throughout the study. Glucagon was infused at a basal rate until the beginning of exercise, when the rate was either 1) gradually increased to simulate the glucagon response to exercise (n = 5) or 2) unchanged to maintain basal glucagon (n = 5). Insulin was infused during the equilibration and basal periods at rates designed to achieve stable euglycemia. The insulin infusion was reduced in both protocols to simulate the exercise-induced insulin decrement. These studies show that the exercise-induced increase in glucagon is 1) essential for the increase in hepatic Gln uptake and fractional extraction, 2) required for the full increment in ureagenesis, 3) required for the specific transfer of the Gln amide nitrogen to urea, and 4) unrelated to the increase in gut fractional Gln extraction. These data show, by use of the physiological perturbation of exercise, that glucagon is a physiological regulator of hepatic Gln metabolism in vivo.     

Insect Trypsin Modulating Oostatic Factor (Neb-TMOF) and Its Analogs: Preliminary Structure/Biological Function Relationship Studies

Neb-TMOF, the trypsin modulating oostatic factor of gray fleshfly Neobellieria bullata, is a hexapeptide with the following sequence: H-Asn-Pro-Thr-Asn-Leu-His-OH. It has been isolated from vitellogenic ovaries in 1994. TMOF, the newly discovered insect peptide, inhibits trypsin biosynthesis in the gut, lowers yolk polypeptide concentration in the hemolymph and strongly inhibits ecdysone biosynthesis by larval ring glands. It is interesting that this short non-protected peptide contains in its molecule two Asn residues at positions 1 and 4 and His at its C-terminus. To obtain information about the role of the His-6 and Asn-4 residues we synthesised two series of Neb-TMOF analogs, modified: (1) in position 6 by D-His (I), His(Bzl) (II) and Phe(p-X) derivatives, where X = NH₂ (III), NO₂ (IV), OEt (V) and OH (VI) and (2) in position 4 by such amino acid residues as Ser (VII), Thr (VIII), Gly (IX), Asp (X), Glu (XI) and D-Asn (XII). The influence of these peptides on trypsin biosynthesis in N. bullata was determined in vivo. In preliminary investigations, we found that Neb-TMOF, [Phe(NH₂)⁶], and [Phe(NO₂)⁶]-Neb-TMOF inhibited trypsin biosynthesis, whereas [D-His)⁶]- and [D-His(Bzl)⁶]-Neb-TMOF were inactive. In further biological studies performed in vitro on heart of Tenebrio molitor we found that Neb-TMOF and [Phe(p-NH₂)⁶-Neb-TMOF showed weak cardioexcitatory activity, about 30% of the cardioexcitatory activity of proctolin, an insect neuromodulating peptide.     

Enhanced Mitochondrial Superoxide Scavenging Does Not Improve Muscle Insulin Action in the High Fat-Fed Mouse

Improving mitochondrial oxidant scavenging may be a viable strategy for the treatment of insulin resistance and diabetes. Mice overexpressing the mitochondrial matrix isoform of superoxide dismutase (sod2^tg mice) and/or transgenically expressing catalase within the mitochondrial matrix (mcat^tg mice) have increased scavenging of O₂˙ˉ and H₂O₂, respectively. Furthermore, muscle insulin action is partially preserved in high fat (HF)-fed mcat^tg mice. The goal of the current study was to test the hypothesis that increased O₂˙ˉ scavenging alone or in combination with increased H₂O₂ scavenging (mtAO mice) enhances in vivo muscle insulin action in the HF-fed mouse. Insulin action was examined in conscious, unrestrained and unstressed wild type (WT), sod2^tg, mcat^tg and mtAO mice using hyperinsulinemic-euglycemic clamps (insulin clamps) combined with radioactive glucose tracers following sixteen weeks of normal chow or HF (60% calories from fat) feeding. Glucose infusion rates, whole body glucose disappearance, and muscle glucose uptake during the insulin clamp were similar in chow- and HF-fed WT and sod2^tg mice. Consistent with our previous work, HF-fed mcat^tg mice had improved muscle insulin action, however, an additive effect was not seen in mtAO mice. Insulin-stimulated Akt phosphorylation in muscle from clamped mice was consistent with glucose flux measurements. These results demonstrate that increased O₂˙ˉ scavenging does not improve muscle insulin action in the HF-fed mouse alone or when coupled to increased H₂O₂ scavenging.     

Hyperspectral and Thermal Imaging of Oilseed Rape (Brassica napus) Response to Fungal Species of the Genus Alternaria

In this paper, thermal (8-13 µm) and hyperspectral imaging in visible and near infrared (VNIR) and short wavelength infrared (SWIR) ranges were used to elaborate a method of early detection of biotic stresses caused by fungal species belonging to the genus Alternaria that were host (Alternaria alternata, Alternaria brassicae, and Alternaria brassicicola) and non-host (Alternaria dauci) pathogens to oilseed rape (Brassica napus L.). The measurements of disease severity for chosen dates after inoculation were compared to temperature distributions on infected leaves and to averaged reflectance characteristics. Statistical analysis revealed that leaf temperature distributions on particular days after inoculation and respective spectral characteristics, especially in the SWIR range (1000-2500 nm), significantly differed for the leaves inoculated with A. dauci from the other species of Alternaria as well as from leaves of non-treated plants. The significant differences in leaf temperature of the studied Alternaria species were observed in various stages of infection development. The classification experiments were performed on the hyperspectral data of the leaf surfaces to distinguish days after inoculation and Alternaria species. The second-derivative transformation of the spectral data together with back-propagation neural networks (BNNs) appeared to be the best combination for classification of days after inoculation (prediction accuracy 90.5%) and Alternaria species (prediction accuracy 80.5%).