Interspecific differences in root architecture among maize and triticale genotypes grown under drought,waterlogging and soil compaction

Environmental stresses (soil compaction, drought, waterlogging) cause changes in plants’ root system structure, also affecting the growth of above-ground parts. The aim of this study was to estimate phenotypic variation among maize and triticale genotypes in root penetration ability through petrolatum-wax-layer (RPA). Also, the effect of shortage or excess of soil water on dry matter of shoots and roots and morphological changes in root system structure in sensitive and resistant maize and triticale genotypes grown in low or high soil compaction level was evaluated. To estimate RPA index, the petrolatum-wax-layer method (PWL) was used. The strength of three petrolatum-wax concentrations 60, 50 and 40 % was 0.52, 1.07 and 1.58 MPa, respectively. High coefficients of variation (CV) were observed in 0.52 and 1.07 MPa and for maize were 19.2 and 21.7 %, and for triticale, 12.5 and 18.3 %, respectively. The data indicate that the use of PWL technique is an effective screening method, and makes it possible to divide the genotypes into resistant and sensitive groups. The second part of this study investigated a multistress effect of soil compaction combined with drought or waterlogging on root and shoot growth and morphological changes in root system structure of maize and triticale genotypes differing in susceptibility to environmental stresses. Seedlings were grown for 4 weeks in root-boxes under conditions of low (LSC 1.1 g cm^?3) or severe (SSC 1.6 g cm^?3) soil compaction. Drought or waterlogging stresses were applied for 2 weeks from 14th to 28th day. In comparison to LSC treatment, in SSC treatment the decrease in dry matter of shoots and roots was greater for sensitive genotypes of maize and triticale (Ancora, CHD-147). Soil drought or waterlogging caused greater decrease of dry matter of shoots and roots in seedlings grown in SSC in comparison to LSC. The root penetration index (RPI) was estimated as a ratio of root dry matter in 15–40 cm root-box layer to total root dry matter. On the basis of RPI it was possible to group the genotypes according to their ability to distribute roots in soil profile. In comparison to LSC, SSC exerted a strong influence on the length of seminal and seminal adventitious roots, as well as the number and length of L- and S-type lateral roots developed on seminal and nodal roots. In both species the restriction effect of soil compaction on number and length of roots was more severe in sensitive (Ankora, CHD-147) than in resistant (Tina, CHD-247) genotypes. The restriction in roots propagation was greater in triticale than in maize. Exposure to drought or waterlogging in the case of genotypes grown in LSC and SSC treatments caused a decrease in number and length of particular components of root system structure. In both species the decrease of root number and length in plants grown under waterlogging was greater than under drought. The observed changes in root system were greater in sensitive (Ankora, CHD147) than in resistant (Tina, CHD-247) genotypes. Statistically significant correlations were found between RPA and RPI and also between these indexes and soil compaction, drought and waterlogging susceptibility indexes. This indicates that genotypes resistant to soil compaction were resistant to drought or waterlogging and also that genotypes resistant to drought were resistant to waterlogging.     

Accelerated degradation of adenine nucleotide in erythrocytes of patients with chronic renal failure

Recently, we have shown that erythrocytes obtained from patients with chronic renal failure (CRF) exhibited an increased rate of ATP formation from adenine as a substrate. Thus, we concluded that this process was in part responsible for the increase of adenine nucleotide concentration in uremic erythrocytes. There cannot be excluded however, that a decreased rate of adenylate degradation is an additional mechanism responsible for the elevated ATP concentration. To test this hypothesis, in this paper we compared the rate of adenine nucleotide breakdown in the erythrocytes obtained from patients with CRF and from healthy subjects.Using HPLC technique, we evaluated: (1) hypoxanthine production by uremic RBC incubated in incubation medium: (a) pH 7.4 containing 1.2 mM phosphate (which mimics physiological conditions) and (b) pH 7.1 containing 2.4 mM phosphate (which mimics uremic conditions); (2) adenine nucleotide degradation (IMP, inosine, adenosine, hypoxanthine production) by uremic RBC incubated in the presence of iodoacetate (glycolysis inhibitor) and EHNA (adenosine deaminase inhibitor). The erythrocytes of healthy volunteers served as control.The obtained results indicate that adenine nucleotide catabolism measured as a hypoxanthine formation was much faster in erythrocytes of patients with CRF than in the cells of healthy subjects. This phenomenon was observed both in the erythrocytes incubated at pH 7.4 in the medium containing 1.2 mM inorganic phosphate and in the medium which mimics hyperphosphatemia (2.4 mM) and metabolic acidosis (pH 7.1). The experiments with EHNA indicated that adenine nucleotide degradation proceeded via AMP-IMP-Inosine-Hypoxanthine pathway in erythrocytes of both patients with CRF and healthy subjects. Iodoacetate caused a several fold stimulation of adenylate breakdown. Under these conditions: (a) the rate of AMP catabolites (IMP + inosine + adenosine + hypoxanthine) formation was substantially higher in the erythrocytes from patients with CRF; (b) in erythrocytes of healthy subjects degradation of AMP proceeded via IMP and via adenosine essentially at the same rate; (c) in erythrocytes of patients with CRF the rate of AMP degradation via IMP was about 2 fold greater than via adenosine.The results presented in this paper suggest that adenine nucleotide degradation is markedly accelerated in erythrocytes of patients with CRF.     

Properties of monocytes generated from haematopoietic CD34+ stem cells from bone marrow of colon cancer patients

Monocytes exhibit direct and indirect antitumour activities and may be potentially useful for various forms of adoptive cellular immunotherapy of cancer. However, blood is a limited source of them. This study explored whether monocytes can be obtained from bone marrow haematopoietic CD34⁺ stem cells of colon cancer patients, using previously described protocol of expansion and differentiation to monocytes of cord blood-derived CD34⁺ haematopoietic progenitors. Data show that in two-step cultures, the yield of cells was increased approximately 200-fold, and among these cells, up to 60 % of CD14⁺ monocytes were found. They consisted of two subpopulations: CD14⁺⁺CD16⁺ and CD14⁺CD16^?, at approximately 1:1 ratio, that differed in HLA-DR expression, being higher on the former. No differences in expression of costimulatory molecules were observed, as CD80 was not detected, while CD86 expression was comparable. These CD14⁺ monocytes showed the ability to present recall antigens (PPD, Candida albicans) and neoantigens expressed on tumour cells and tumour-derived microvesicles (TMV) to autologous CD3⁺ T cells isolated from the peripheral blood. Monocytes also efficiently presented the immunodominant HER-2/neu_369–377 peptide (KIFGSLAFL), resulting in the generation of specific cytotoxic CD8⁺ T lymphocytes (CTL). The CD14⁺⁺CD16⁺ subset exhibited enhanced cytotoxicity, though nonsignificant, towards tumour cells in vitro. These observations indicate that generation of monocytes from CD34⁺ stem cells of cancer patients is feasible. To our knowledge, it is the first demonstration of such approach that may open a way to obtain autologous monocytes for alternative forms of adaptive and adoptive cellular immunotherapy of cancer.     

<Emphasis Type="Italic">INFLORESCENCE DEFICIENT IN ABSCISSION-like</Emphasis> is an abscission-associated and phytohormone-regulated gene in flower separation of <Emphasis Type="Italic">Lupinus luteus</Emphasis>

Abscission is a natural process that occurs to facilitate shedding of no longer needed organs, but on the other hand, can be triggered by certain environmental conditions, e.g. biotic or abiotic stresses. Regardless of the stimuli, organ shedding takes place specifically at the abscission zone (AZ). A signaling pathway that controls this process in Arabidopsis thaliana from ligand to receptors has been proposed. However, knowledge concerning the influence of plant hormones on these molecular elements still remains enigmatic. Excessive and premature flower abscission in the crop species Lupinus luteus L. is a process of substantial interest to the agricultural industry, as it can affect yield. Our strategy combined molecular studies, comprehensive ultrastructural and histological analysis, as well as exogenous hormone treatment to describe the contribution of the Lupinus IDA-like gene in flower abscission. In the AZ of the naturally abscised flowers, the differentiation of morphologically distinct cells characterized by progressive degradation processes was accompanied by LlIDL mRNA accumulation. A similar effect was observed following early steps of AZ activation and after abscisic acid or ethylene treatments. These phytohormones, previously pointed out as key stimulators of flower separation, altered the temporal expression pattern of LlIDL. Exogenous EPIP peptide synthesized on the basis of LlIDL sequence, significantly increased flower abortion rate, which indicates that this motif governs protein activity. In conclusion, our data provide new evidence for LlIDA involvement in both the early and late events of flower abscission supported by detailed spatiotemporal characterization of AZ cell structure and ultrastructure.     

Aerobic exercise training reduces cannabis craving and use in non-treatment seeking cannabis-dependent adults

Background

Cannabis dependence is a significant public health problem. Because there are no approved medications for this condition, treatment must rely on behavioral approaches empirically complemented by such lifestyle change as exercise.

Aims

To examine the effects of moderate aerobic exercise on cannabis craving and use in cannabis dependent adults under normal living conditions.

Design

Participants attended 10 supervised 30-min treadmill exercise sessions standardized using heart rate (HR) monitoring (60–70% HR reserve) over 2 weeks. Exercise sessions were conducted by exercise physiologists under medical oversight.

Participants

Sedentary or minimally active non-treatment seeking cannabis-dependent adults (n = 12, age 25±3 years, 8 females) met criteria for primary cannabis dependence using the Substance Abuse module of the Structured Clinical Interview for DSM-IV (SCID).

Measurements

Self-reported drug use was assessed for 1-week before, during, and 2-weeks after the study. Participants viewed visual cannabis cues before and after exercise in conjunction with assessment of subjective cannabis craving using the Marijuana Craving Questionnaire (MCQ-SF).

Findings

Daily cannabis use within the run-in period was 5.9 joints per day (SD = 3.1, range 1.8–10.9). Average cannabis use levels within the exercise (2.8 joints, SD = 1.6, range 0.9–5.4) and follow-up (4.1 joints, SD = 2.5, range 1.1–9.5) periods were lower than during the run-in period (both P<.005). Average MCQ factor scores for the pre- and post-exercise craving assessments were reduced for compulsivity (P  = .006), emotionality (P  = .002), expectancy (P  = .002), and purposefulness (P  = .002).

Conclusions

The findings of this pilot study warrant larger, adequately powered controlled trials to test the efficacy of prescribed moderate aerobic exercise as a component of cannabis dependence treatment. The neurobiological mechanisms that account for these beneficial effects on cannabis use may lead to understanding of the physical and emotional underpinnings of cannabis dependence and recovery from this disorder.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00838448","term_id":"NCT00838448"}}NCT00838448]     

Mesenchymal Stem Cells Modified with a Single-Chain Antibody against EGFRvIII Successfully Inhibit the Growth of Human Xenograft Malignant Glioma

Background

Glioblastoma multiforme is the most lethal brain tumor with limited therapeutic options. Antigens expressed on the surface of malignant cells are potential targets for antibody-mediated gene/drug delivery.

Principal Findings

In this study, we investigated the ability of genetically modified human mesenchymal stem cells (hMSCs) expressing a single-chain antibody (scFv) on their surface against a tumor specific antigen, EGFRvIII, to enhance the therapy of EGFRvIII expressing glioma cells in vivo. The growth of U87-EGFRvIII was specifically delayed in co-culture with hMSC-scFvEGFRvIII. A significant down-regulation was observed in the expression of pAkt in EGFRvIII expressing glioma cells upon culture with hMSC-scFvEGFRvIII vs. controls as well as in EGFRvIII expressing glioma cells from brain tumors co-injected with hMSC-scFvEGFRvIII in vivo. hMSC expressing scFvEGFRvIII also demonstrated several fold enhanced retention in EGFRvIII expressing flank and intracranial glioma xenografts vs. control hMSCs. The growth of U87-EGFRvIII flank xenografts was inhibited by 50% in the presence of hMSC-scFvEGFRvIII (p<0.05). Moreover, animals co-injected with U87-EGFRvIII and hMSC-scFvEGFRvIII intracranially showed significantly improved survival compared to animals injected with U87-EGFRvIII glioma cells alone or with control hMSCs. This survival was further improved when the same animals received an additional dosage of hMSC-scFvEGFRvIII two weeks after initial tumor implantation. Of note, EGFRvIII expressing brain tumors co-injected with hMSCs had a lower density of CD31 expressing blood vessels in comparison with control tumors, suggesting a possible role in tumor angiogenesis.

Conclusions/Significance

The results presented in this study illustrate that genetically modified MSCs may function as a novel therapeutic vehicle for malignant brain tumors.     

Monitoring changes in anthocyanin and steroid alkaloid glycoside content in lines of transgenic potato plants using liquid chromatography/mass spectrometry

Transgenic potato plants overexpressing and repressing enzymes of flavonoids biosynthesis were created and analyzed. The selected plants clearly showed the expected changes in anthocyanins synthesis level. Overexpression of a DNA encoding dihydroflavonol 4-reductase (DFR) in sense orientation resulted in an increase in tuber anthocyanins, a 4-fold increase in petunidin and pelargonidin derivatives. A significant decrease in anthocyanin level was observed when the plant was transformed with a corresponding antisense construct. The transformation of potato plants was also accompanied by significant changes in steroid alkaloid glycosides (SAG) level in transgenic potato tuber. The changes in SAGs content was not dependent on flavonoid composition in transgenic potato. However, in an extreme situation where the highest (DFR11) or the lowest (DFRa3) anthocyanin level was detected the positive correlation with steroid alkaloid content was clearly visible. It is suggested that the changes in SAGs content resulted from chromatin stressed upon transformation. A liquid chromatography/mass spectrometry (LC/MS) system with electrospray ionization was applied for profiling qualitative and quantitative changes of steroid alkaloid glycosides in tubers of twelve lines of transgenic potato plants. Except alpha-chaconine and alpha-solanine, in the extracts from dried tuber skin alpha-solamargine and alpha-solasonine, triglycosides of solasonine, were identified in minor amounts, triglycosides of solanidine dehydrodimers were also recognized.     

A Supposed Eupelycosaur Body Impression from the Early Permian of the Intra-Sudetic Basin,Poland

We describe a new specimen of a supposed Paleozoic tetrapod body impression from the Lower Permian S?upiec Formation in the Intra-Sudetic Basin, Poland. The size, integument morphology of belly and part of tail imprints, and the morphology of a well-preserved pes track diagnose the specimen and readily distinguish it from other described specimens of body impressions of Paleozoic tetrapods. The eupelycosaur identity of this new specimen is based on the identification of the footprint Dimetropus leisnerianus (Geinitz, 1863 Geinitz, H. B. 1863. Beiträge zur Kenntnis der organischen Überreste in der Dyas (oder permischen Formation zum Theil) und über den Namen Dyas. Neues Jahrbuch für Mineralogie, Geologie und Paläontologie, : 385–398.  [Google Scholar]), which is connected with the inferred body imprint. The morphology of integument impressions indicates the presence of the various-sized square or rectangular-shaped scales on the bottom part of the belly and tail of this eupelycosaurid trackmaker.     

Inhibition of chitosan-immobilized urease by slow-binding inhibitors: Ni, F and acetohydroxamic acid

The inhibitions by Ni²⁺ and F⁻ ions and by acetohydroxamic acid of jack bean urease covalently immobilized on chitosan membrane was studied (pH 7.0, 25°C) and compared with those of the native enzyme. The reaction progress curves of the immobilized urease-catalyzed hydrolysis of urea were recorded in the absence and presence of the inhibitors. They revealed that the inhibitions are of the competitive slow-binding type similar to those of native urease. The immobilization weakened the inhibitory effect of the inhibitors on urease as measured by the inhibition constants K_i^*. The increase in their values: 17.9-fold for Ni²⁺, 26.5-fold for F⁻ and 1.7-fold for acetohydroxamic acid, was accounted for by environmental effects generated by heterogeneity of the urease–chitosan system: (1) mass transfer limitations imposed on substrate and reaction product in the external solution, and (2) the increase in local pH on the membrane produced by both the enzymatic reaction and the electric charge of the support. By relating the K_M/K_i^* ratio to the electrostatic potential of chitosan it was found that while the reduced Ni²⁺ inhibition is mainly brought about by the potential, inhibition by acetohydroxamic acid is independent of the potential, and the acid inhibits urease in its non-ionic form. The reduction in F⁻ inhibition was ascribed to the increased pH in the local environment of the immobilized enzyme.