Trace element correlations in the blood of indian women with breast cancer

Fourteen minor (Na, K, P, Fe) and trace (Br, Co, Cr, Cs, Hg, Rb, Sb, Se, Sr, Zn) elements have been determined in pre and postoperative blood samples of 10 breast-cancer-affected. Indian women and compared with controls. The study showed elevation of Cr, Hg, Fe, Rb, Sb, and Zn and lowering of Se, K, P, and Sr contents in the blood of cancer patients. Most elemental contents in pre and postoperative stages remain unaltered except Br, Co, and Sb. Statistical significance of Fe, Se, Zn, and Hg levels has been tested by box plots. Lowering of Se in blood (-54.4%) is correlated with its enhancement in cancerous breast tissue (94.7%) of various clinical stages. Se/Zn and Se/Fe ratios are lowered in the blood of cancer patients, whereas Na/K ratio is only marginally enhanced. An attempt has been made to correlate Se levels with the dietary intake and breast cancer risk vis-a-vis American and Japanese women.     

Comparison between levels of trace elements in normal and cancer inoculated mice by XRF and PIXE

Determination of Rb, Br, Se, Zn, Cu, Fe, and Br/Rb ratio in tissues of mice inoculated with colon and melanoma cancer cells is described. A group of 19 Balb/c mice inoculated with C26 colon carcinoma, 4 C57B1/6 mice inoculated with B16 melanoma, and 13 control mice of both kinds were under investigation. The study was conducted on samples of blood, liver, kidneys, colon, and skin, and the trace element levels in normal and inoculated mice were compared. The inoculation was by subcutaneous injection either at the back or intrafootpad. The blood samples were taken 1, 2, and 3 wk after inoculation, and after 4 wk all the animals were sacrificed. Two nondestructive, complementary analytical methods were used: a modified X-ray fluorescence (XRF) for solid tissue and particleinduced X-ray emission (PIXE) for blood samples. The detection limit (DL) in the PIXE method was 0.35 (μg/g dry wt in 600 s counting time and in XRF, 1 μg/g dry sample for Rb, Br, Se and Zn and 2 μg/g for Cu and Fe in 200 s counting time. In all the cases studied, cancerous tissue developed at the site of the injection, and a significant difference in the trace element levels was observed between tissue samples obtained from normal and inoculated mice. The most pronounced effect was an increase in Rb level in the tumor by a factor ranging between 4 and 10 relative to normal tissue, with a corresponding decrease in the Br/Rb ratio (p < 0.05). Smaller changes were found in the Br, Se, Zn, and K levels. The changes in trace element levels in the inner organs were much smaller and seem to be influenced by the site of injection.     

Spatial distributions and net deposition rates of mineral elements in the elongating wheat (Triticum aestivum L.) leaf under saline soil conditions

Wheat leaf growth is known to be spatially affected by salinity. The altered spatial distribution of leaf growth under saline conditions may be associated with spatial changes in tissue mineral elements. The objective of this study was to evaluate the spatial distributions of mineral elements and their net deposition rates in the elongating and mature zones of leaf 4 of the main stem of spring wheat (Triticum aestivum L. cv. Lona) during its linear growth phase under saline soil conditions. Plants were grown in an illitic-chloritic silty loam with 0 and 120 mM NaCl. Three days after emergence of leaf 4, sampling was begun at 3 and 13 h into the 16-h light period. Spatial distributions of fresh weight (FW), dry weight (DW), and Na⁺, K⁺, Cl⁻, NO⁻ ₃, Ca²⁺, Mg²⁺, total P, and total N in the elongating and mature tissues were determined on a millimeter scale. The patterns of spatial distribution of Na⁺, Cl⁻, K⁺, NO₃ ⁻, and Ca²⁺ in the growing leaves were affected by salinity, while those of Mg²⁺, total P, and total N were not. Sodium, K⁺, Cl⁻, Ca²⁺, Mg²⁺, and total N concentrations (mmol · kg⁻¹ FW) were consistently higher at 120 mM NaCl than at 0 mM NaCl along the leaf axis from the leaf base, whereas NO₃ ⁻ concentration was lower at 120 mM NaCl. Deposition rates of all nutrients were greatest in the elongation zone. The elongation zone was the strongest sink for mineral elements in the leaf tissues. Local net deposition rates of Na⁺, Cl⁻, Ca²⁺, and Mg²⁺ (mmol · kg⁻¹ FW · h⁻¹) in the most actively elongating zone were enhanced by 120 mM NaCl, whereas for NO₃ ⁻ this was depressed. The lower supply of NO⁻ ₃ to growing leaves may be responsible for the inhibition of growth under saline conditions. Higher tissue concentrations of Na⁺ and Cl⁻ may cause ion imbalance but probably did not result in ion toxicity in the growing leaves. Potassium, Ca²⁺, Mg²⁺, total P, and total N are less plausibly responsible for the reduction in leaf growth in this study. Higher tissue K⁺ and Ca²⁺ concentrations at 120 mM NaCl are probably due to the presence of high Ca²⁺ in the soil of this study. Received: 13 March 1997 / Accepted: 9 June 1997     

Repeated DNA elements in planarians of the Dugesia gonocephala group (Platyhelminthes,Tricladida)

The results of the isolation of repetitive DNA elements in the genome of Dugesia etrusca, a species of the Dugesia gonocephala group, are reported. These sequences, about 1.4 kb long, represent only a part of longer interspersed genomic units (De1 family) and appear to be limited to the genome of some planarians of this group, as indicated by a Southern blot analysis performed in different species and populations. The genomic relationships among different species and populations of the D. gonocephala group are discussed in relation to the results obtained in the present work. This revised version was published online in July 2006 with corrections to the Cover Date.     

Leaf mineral concentrations of Erica arborea, Juniperus communis and Myrtus communis growing in the proximity of a natural CO2 spring

Leaf mineral concentrations of co‐occurring Erica arborea, Juniperus communis and Myrtus communis were measured at bimonthly intervals throughout a year in a natural CO₂ spring and in a nearby control site with similar soil chemistry in a Mediterranean environment. There were different responses to the elevated [CO₂] (c. 700 μL L^?1) of the spring site plants depending on the element and the species. In the CO₂ spring site K, Ca, Mg, Mn, Al, Fe, and Ti leaf concentrations and the ratio C/N showed significant greater values in at least one or two of the three species. Leaf S concentration were greater in all three species. Leaf concentrations of N, Sr, Co, and B were lower in at least one or two species, and those of C and Ba were lower in all the three studied species near the CO₂ spring. P, Na, Zn, Si, Cu, Ni, Cr, Pb, Mo, V and Cd leaf concentrations and the specific leaf area (SLA, measured in Myrtus communis) did not show any consistent or significant pattern in response to the elevated [CO₂] of the spring site. There was a slight trend towards maximum concentrations of most of these elements during autumn–winter and minimum values during the spring season, especially in Myrtus communis. Multivariate principal component analyses based on the leaf elemental concentrations clearly differentiated the two sites and the three species. Lower concentrations at the spring site were not the result of a dilution effect by increased structural or nonstructural carbon. In contrast to most experimental studies of CO₂ enrichment, mainly conducted for short periods, several of these elements had greater concentrations in the CO₂ spring site. Nutrient acclimation and possible causes including decreased nutrient export, increased nutrient uptake capacity, photosynthetic down‐regulation, Mediterranean water stress, and higher H₂S concentration in the spring site are discussed.     

Potential Role of Transposable Elements in the Rapid Reorganization of the Fusarium oxysporum Genome

The activity of several families of transposable elements (TEs) in the genome of Fusarium oxysporum represents a potential source of karyotypic instability. We investigated transposon-mediated chromosome rearrangements by analyzing the karyotypes of a set of strains in which transposition events had occurred. We uncovered exceptional electrophoretic karyotype (EK) variability, in both number and size of chromosomal bands. We showed that EK differences result from chromosomal translocations, large deletions, and even more complex rearrangements. We also revealed many duplicated chromosomal regions. By following transposition of two elements and analyzing the distribution of different families of TEs on whole chromosomes, we find (i) no evidence of chromosomal breakages induced by transposition, (ii) a clustering of TEs in some regions, and (iii) a correlation between the high level of chromosomal polymorphism and the concentration of TEs. These results suggest that chromosome length polymorphisms likely result from ectopic recombination between TEs that can serve as substrates for these changes.     

Dissection of cis-regulatory elements of the Drosophila gene Serrate

 The Drosophila gene Serrate encodes a membrane spanning protein, which is expressed in a complex pattern during embryogenesis and larval stages. Loss of Serrate function leads to larval lethality, which is associated with several morphogenetic defects, including the failure to develop wings and halteres. Serrate has been suggested to act as a short-range signal during wing development. It is required for the induction of the organising centre at the dorsal/ventral compartment boundary, from which growth and patterning of the wing is controlled. In order to understand the regulatory network required to control the spatially and temporally dynamic expression of Serrate, we analysed its cis-regulatory elements by fusing various genomic fragments upstream of the reporter gene lacZ. Enhancer elements reflecting the expression pattern of endogenous Serrate in embryonic and postembryonic tissues could be confined to 26 kb of genomic DNA, including 9 kb of transcribed region. Expression in some embryonic tissues is under the control of multiple enhancers located in the 5’ region and in intron sequences. The data presented here provide the tools to unravel the genetic network which regulates Serrate during different developmental stages in diverse tissues. Received: 27 March 1998 / Accepted: 17 May 1998     

The homeotic Macho mutant of Antirrhinum majus reverts to wild-type or mutates to the homeotic plena phenotype

Plants of Antirrhinum majus carrying the semidominant Macho alleles of the plena gene display carpelloid sepals and staminoid petals, but the two inner flower whorls of stamens and carpels are normal and produce fertile gametes. In the recessive plena mutant, in contrast, the two outer whorls are normal whereas the stamens are largely or entirely petaloid and the carpels sepaloid, thus producing weakly male-fertile or fully sterile lines. Two new plena and two new Macho alleles have been induced in transposon tagging experiments. Genetic and molecular analysis revealed that the two contrasting mutant phenotypes are caused by mutations in one and the same gene: Several wild-type plants appeared among 27 000 F1 plants of a cross between Macho female plants and wild-type males bearing the active transposons Taml and Tam3. One of these plants segregated plena mutants, three showed reversions to wild-type and another two segregated Macho plants, possibly representing somatic reversions. Additional evidence was provided by an allelism test of Macho × plena. Molecular analysis has independently corroborated the genetical results. Moreover, the double mutant Macho/deficiens shows only carpels and plena/deficiens only sepals, which is in accord with combinatorial models for homeotic flower formation presented recently.     

Molecular evolutionary characterization of an Activator (Ac)-like transposable element sequence from pearl millet (Pennisetum glaucum) (Poaceae)

We present data on the evolution of the Ac/Ds family of transposable elements in select grasses (Poaceae). A defective Ac-like element was cloned from a DNA library of the grass Pennisetum glaucum (pearl millet) and its entire 4531 bp sequence has been determined. When the pearl millet Ac-like sequence is aligned with the maize Ac sequence, it is found that there is approximately 70% DNA similarity in the central region spanning most of maize Ac exon II and all of exon III. In addition, there are two smaller regions of similarity at the Ac terminii. Besides these three major structural similarities, Pennisetum Ac has two large regions, one 5 and one 3, that show little similarity to Zea Ac. Furthermore, most of the sequences corresponding to intron II in maize Ac are absent in pearl millet Ac. Kimura's evolutionary distance between the central region of maize and pearl millet Ac sequences is estimated to be 0.429±0.020 nucleotide substitutions per site. This value is not significantly different from the average number of synonymous substitutions for coding regions of the Adh1 gene between maize and pearl millet, which is 0.395±0.051 nucleotide substitutions per site. If we assume Ac and Adh1 divergence times are equivalent between maize and pearl millet, then the above calculations suggest Ac-like sequences have probably not been strongly constrained by natural selection. Conserved DNA and amino acid sequence motifs are also examined. The level of DNA sequence divergence between maize and pearl millet Ac sequences, the estimated date when maize and pearl millet diverged (25–40 million years ago), coupled with their reproductive isolation/lack of current genetic exchange, all support the theory that Ac-like sequences have not been recently introduced into pearl millet from maize. Instead, Ac-like sequences were probably present in the progenitor of maize and pearl millet and have thus existed in the grasses for at least 25 million years.