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FLT3-mutations are diagnosed in 25-30% of patients with acute myeloid leukemia (AML) and are associated with a poor prognosis. AML is associated with the overproduction of reactive oxygen species (ROS), which drives genomic instability through the oxidation of DNA bases, promoting clonal evolution, treatment resistance and poor outcomes. ROS are also important second messengers, triggering cysteine oxidation in redox sensitive signaling proteins, however, the specific pathways influenced by ROS in AML remain enigmatic. Here we have surveyed the posttranslational architecture of primary AML patient samples and assessed oncogenic second messenger signaling. Signaling proteins responsible for growth and proliferation were differentially oxidized and phosphorylated between patient subtypes either harboring recuring mutation in FLT3 compared to patients expressing the wildtype-FLT3 receptor, particularly those mapping to the Src family kinases (SFKs). Patients harboring FLT3-mutations also showed increased oxidative posttranslational modifications in the GTPase Rac activated-NADPH oxidase-2 (NOX2) complex to drive autocratic ROS production. Pharmacological and molecular inhibition of NOX2 was cytotoxic specifically to FLT3-mutant AMLs, and reduced phosphorylation of the critical hematopoietic transcription factor STAT5 and MAPK/ERK to synergistically increase sensitivity to FLT3-inhibitors. NOX2 inhibition also reduced phosphorylation and cysteine oxidation of FLT3 in patient derived xenograft mouse models in vivo, highlighting an important link between oxidative stress and oncogenic signaling. Together, these data raise the promising possibility of targeting NOX2 in combination with FLT3-inhibitors to improve treatment of FLT3-mutant AML.One Sentence SummaryFLT3-precision therapies have entered the clinic for AML however, their durability is limited. Here we identify the Rac-NOX2 complex as the major driver of redox second messenger signaling in FLT3-mutant AML. Molecular and pharmacological inhibition of NOX2 decreased FLT3, STAT5 and MEK/ERK signaling to delay leukemia progression, and synergistically combined with FLT3 inhibitors.

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Background: Recent development of LC methods for the determination of total folates (vitamin B9) in complex matrixes have been hindered by vitamer interconversion and yield variability. The official microbiological method (AOAC Official Methods of Analysis 944.12 and 960.46) uses an end point turbidity reading to determine folate concentration. However, when measuring complex matrixes, shifts are observed in the growth curves of the microorganism and inaccuracies are introduced to this quantification method. Objective/Methods: In addition to the tri-enzyme digestion of the standard microbiological method, we have applied enzyme modeling of the initial velocity of bacterial growth using Michaelis-Menten kinetics to achieve more accurate and reproducible determinations of total folates. Results/Conclusions: Accuracy determined through spike recovery in Infant/Adult Nutritional Drink and a complex vitamin matrix gave values acceptable to AOAC standards of 85–110%. Repeatability of the low mass fraction analyte measured at micrograms per 100 g yielded relative standard deviations

Ultra-high curvature single-walled carbon nanotubes (SWCNTs) with diameters down to 0.37 nm were prepared by transformation of FeCp2 peapods to double-walled CNTs (DWCNTs). Results from resonance Raman scattering and high resolution transmission electron microscopy (TEM) were compared to calculations on the molecular dynamical, many electron corrected extended tight binding, and density functional theory (DFT) level. The growth process was found to be catalytic from Fe3C particles inside the tubes with dimensions of a crystallographic unit cell. The electronic structure showed dramatic deviations from tight binding results. The family behavior leads to level crossing already for and transitions. Experimental results fitted well into a Kataura–Popov plot and allowed assignment for the observed Raman lines of the inner tubes. Experimental and calculated radial breathing mode (RBM) frequencies showed a systematic difference indicating a radial expansion of the smallest inner tubes and a radial compression for the larger tubes.

The electronic and the vibrational structure of carbon nanotubes with ultrahigh curvature was systematically studied by resonance Raman scattering, high-resolution transmission electron microscopy (HRTEM), molecular dynamics, and ab initio DFT calculations. The ultrahigh curvature tubes were grown inside commercial HiPco tubes after filling the latter with the small but carbon-rich molecule ferrocene. TEM showed partial filling of the outer tubes with inner tubes and mobility of the latter in the electron beam. The smallest analyzed tube was of (5,0) chirality and had a DFT determined diameter of 0.406 nm and a radial breathing mode frequency of 570 cm(-1). For all inner tubes which had transitions in the visible spectral range, transition energies and RBM frequencies were determined with a resonance width of only 45 meV. Experimentally determined transition energies revealed dramatic deviations up to several electronvolts compared to tight-binding calculations and a significant family spread of more than 2 eV but were in agreement with many electron contribution corrected extended tight-binding results and with results from DFT calculations.

A detailed study on the photoselective Raman response of p-type intercalated single-wall carbon nanotube (SWCNT) is presented. Here, we focus on the high doping region. The shift of the G-line is used to monitor the doping level of the p-type intercalated SWCNT using irontrichloride. Special emphasis is given on the changes in the dispersion of the D- and G'-lines as a function of doping. For very high doping levels a decrease of the slope is observed.

We studied peapods prepared with ferrocene (dicyclopentadienyl iron, Fe(Cp) 2 ) as filling species, which makes CNTs with diameters down to 1.1 nm accessible for filling. Two different single-wall carbon nanotube (SWCNT) samples with mean diameters of 1.1 nm (HiPco) and 1.6 nm (DIPS) were used. Filling was done from the gas phase at elevated temperatures. Sample analysis was done by multifrequency Raman spectroscopy. The Raman response from the encapsulated molecule could be observed through the wall of the CNTs, confirming the encapsulation of the employed molecular species. We observed a sharp decrease of the radial breathing mode intensity for the peapod samples compared to the unfilled CNTs. Ferrocene peapods were transformed to double wall carbon nanotubes (DWCNTs) in a heat induced growth process.

OBJECTIVE: This systematic review assesses the effectiveness of ventral rectopexy (VR) surgery for treatment of rectal prolapse (RP) and rectal intussusception (RI) in adults. Method MEDLINE, EMBASE, Scopus and other relevant databases were searched to identify studies. Randomized controlled trials or nonrandomized studies with more than 10 patients receiving ventral mesh rectopexy surgery were considered for the review. RESULTS: Twelve nonrandomized case series studies with 728 patients in total are included in the review. Seven studies used the Orr-Loygue procedure (VR with posterior rectal mobilization to the pelvic floor) and five studies used VR without posterior rectal mobilization. Overall weighted mean percentage decrease in faecal incontinence (FI) rate was 45%. The weighted mean percentage decrease in constipation rate was 24%. Weighted mean recurrence rate was 3.4%. CONCLUSIONS: There are limitations in published literature on VR. The available data indicate that VR has low recurrence and improves FI in patients suffering from these conditions. There is a greater reduction in postoperative constipation if VR is used without posterior rectal mobilization.

Molecular nanostructures are excellent systems to study surface enhanced Raman scattering (SERS), since monolayers or sub-monolayers are expected to provide maximum scattering enhancement. The SERS enhancement is due to a plasma induced field enhancement by metallic nanoparticles. By this effect the Raman response of molecules in the immediate neighborhood of the particles can be dramatically increased. We investigated the SERS effect of Ag colloids on glass substrates and on lithographically produced nanostructures of gold and aluminum on silicon and ITO-glass. For testing extremely thin layers (monolayers and submonolayers) of 4-octyl-4'-cyanobiphenyl (liquid crystal 8CB) were prepared. The observed enhancement for 8CB on Ag colloids was about 103. Enhancement factors for the lithographic structures were initially below 100. To increase the enhancement the An nanostructures were coated with a 20 nm thick Ag-layer. Optimisation of the Ag nanoparticle geometry was investigated as an alternative SERS improvement routine. The viability of iR the chip structures for multiple usage was tested. The experimental analysis was supported by calculations of the) SERS cross-section for different structure geometries.

Raman scattering from double-walled carbon nanotubes is reported with particular emphasis on the response from the radial breathing mode (RBM) of the inner-shell tubes. The unexpected large number of very narrow lines observed is explained by the growth of one and the same inner tube type in different outer tubes in a highly shielded environment. The response of the RBM and of the G-line is used to analyze the transition from peapods to double-walled carbon nanotubes. During the transformation process the Raman response disappears for a short time, indicating the existence of some Raman dark matter. By preparing the starting peapods from heterofullerenes such as (C59N)2 or 13C-substituted fullerenes, hetero-nanotubes can be grown where nitrogen or the 13C atoms are incorporated into the inner tube wall. Copyright © 2007 John Wiley & Sons, Ltd.

We report on the preparation and subsequent Raman analysis of carbon nanotube peapods, using the fullerene C 60 and its heterofullerene derivative (C 59 N) 2 as filling materials. The filling with (C 59 N) 2 was done from liquid solution at room temperature and from the gas phase at elevated temperatures. The success of the encapsulation procedure is confirmed through the identification of fingerprint Raman modes and the conversion to double wall nanotubes through heating to 1250 °C. The 2D mode of double wall nanotubes made from (C 59 N) 2 peapods is observed to be downshifted compared to the same mode in double wall nanotubes made from C 60 peapods. We interpret this downshift as an evidence for the integration of the nitrogen into the lattice of the inner tube.

Raman scattering is used to study the filling of single wall carbon nanotubes with C60, C59N and anthracene. It is demonstrated how reversible opening and closing of the tubes can be used to check on the success of the filling process. In the case of C59N, filling was performed from the gas phase from 1:1 mixture between C60 and C59N. Comparing the Raman spectra from the encapsulated mixture with the spectra from C60 inside the tubes reveals that most of the molecules have reacted to form either the dimer (C59N)2 or the hetero-dimer C60C59N. Anthracene is demonstrated to enter the tubes but the molecule is subjected to a considerable geometrical change including some loss of hydrogens. Copyright © 2007 John Wiley & Sons, Ltd.

Soybean seeds are a valuable food and feed source because of their high protein and oil content. Conventional breeding has had limited success in increasing both oil and protein. Reducing the amount of cell wall polysaccharide in soybean seed could allow higher protein and oil content, thus increasing their economic value. UDP-glucose dehydrogenase is a key enzyme in cell wall polysaccharide synthesis. To investigate the role of UDP-glucose dehydrogenase in seed development, a transgenic approach was initiated. A new binary vector has been constructed for soybean transformation that has the following features: i) the selectable marker hygromycin phosphotransferase (hpt); ii) placement of the selectable marker adjacent to the T-DNA left border and, iii) an antisense copy of the UDP-glucose dehydrogenase gene driven by the seed-specific vicilin promoter. This genetic construct was engineered to suppress the expression of UDP-glucose dehydrogenase in soybean seeds.

Raman spectra have been demonstrated repeatedly to be a very valuable tool for the analysis of new carbon phases such as fullerenes and single wall carbon nanotubes (SWCNTs). Recently it was demonstrated from TEM analysis that C 60 can be encapsulated into SWCNTs. The structures have been given the name ‘peapods’. The concentration of the encapsulated ‘peas’ and the bonding structure in the tube are still unknown but under heavy discussion. From experience with C 60 and SWCNTs, Raman spectroscopy is expected to be a key technique for the analysis of such structures. In our experiments, we found two modes in the region of the pentagonal pinch mode of C 60 . The resonance behavior for these two modes and their temperature dependence is shown in this paper.

Thermal stability and high-temperature degradation of pristine bisazafullerene (C59N)2 were analyzed by infrared and Raman spectroscopy in the temperature range from 300 to 745 K. The spectra showed a reversible temperature dependence up to 550 K. For higher temperatures an irreversible degradation into disordered graphite was found. Approximately 55% of the material resisted a thermal treatment of 745 K for several hours. A mechanism involving a low stationary concentration of C59N• monomer radical species and a slow graphitization is proposed for the thermolysis of the material. The remarkable thermal stability of pristine bisazafullerene (C59N)2 is ascribed to the low stability of the C59N• monomer radical species, the high activation energy for graphitization, and the absence of other reaction partners under high vacuum conditions.

We report on the evaluation of the distribution of diameters for nanotube samples with a wide variation of mean diameters. Such results were obtained from a detailed analysis of the radial breathing mode Raman response and compared to results obtained from an evaluation of optical spectra and X-ray diffraction pattern. The evaluation of the Raman data needs a well refined analysis as the experimental analysis exhibits a rather complicated and oscillating relation between response and exciting laser. Both, an exact calculation where the density of states was considered explicitly and an approximate calculation were applied. Both models used for the analysis are able to explain several unexpected results from the experiment such as the oscillating behavior of the spectral moments, unusual discontinuities in the first moments of the Raman response for excitation in the IR, a fine structure for the response in optics and Raman, and an up shift of the RBM frequency as compared to qualified ab initio calculations. In detail the first moment and the variance of the spectra were used for the evaluation of the diameter distribution. To obtain good results between experimental and theoretical oscillation pattern the transition energy between the first two van Hove singularities had to be scaled up which is considered as a result from coulomb interaction of the electrons in the tubular material. On the other hand the analysis does not only allow to determine the mean value and the width of the diameter distribution but yields also a value for the average bundle diameters or, alternatively, the strength of the tube-tube interaction. The model used for the analysis of the Raman data is also appropriate to analyze the optical response, at least for the spectral range from 0.5 eV to 3.5 eV. The fine structure in the response for the transitions between the three lowest van Hove singularities is well reproduced and the mean tube diameters and their distribution is obtained in very good agreement with the results from the Raman analysis. From the X-ray analysis the same mean values and comparable distributions for the tube diameters were received whereas the bundle diameters could not be retained with high precision in this case.

Low energy vibrational excitations in single bonded fullerene dimeres (C59N)2 and (C60-)2 and in single wall carbon nanotubes were investigated by Raman spectroscopy. The two isoelectronic and isostructural dimeres exhibited very similar spectra with strongly resonance enhanced lines for the radial modes if excitation was with a red laser. For the biazafullerene for the first time all three geometrically allowed intercage modes could be identified. For the single wall carbon nanotubes the response from the radial breathing mode was analyzed for excitation with 20 different laser lines. The results were found to be consistent with contributions from all geometrically allowed tubes and a strong contribution to the force constant from intercage interaction.

Raman spectra are presented for the single bonded dimeric fullerene (C 60 - ) 2 and compared to optical spectra and Raman spectra of the isostructural and isoelectronic heterofullerene (C59N)2. The spectra of both materials exhibit strong correlations with respect to splitting, line position, and line intensity. This holds for non resonant excitation with blue and green lasers as well as for the strong resonances observed with red lasers. The latter observation is consistent with a downshift for the electronic transition energies as compared to C60. The absorption edge of thin films of (C59N)2 was found at 1.4 eV. The three intercage modes were observed at 82, 103, and 111, and at 88, 98, and 106 cm-1 for (C59N)2 and (C 60 - ) 2 , respectively. A surprising difference was found for the position of the pentagonal pinch modes in the two materials as they were observed at 1461 and at 1451 cm-1, for (C59N)2 and (C 60 - ) 2 , respectively. This is interpreted as a consequence of some characteristic differences in the electronic structure of the two compounds.

Propaquizafop absorption, translocation, metabolism, and effects on acetyl-CoA carboxylase (ACCase) isoforms were examined in chickpea (Cicer arientinum L.). Maximum foliar absorption of propaquizafop, approximately 35% of recovered herbicide, occurred 48 h after treatment. Of the absorbed propaquizafop, approximately 30% was rapidly metabolized to the acid form followed by a slow conversion of the acid to a polar metabolite. Approximately 4% of foliar-applied [14C]propaquizafop was translocated from the treated leaflets within 72 h after application. Chloroplast stromal and cytosolic fractions were isolated from chickpea leaves. Proteins from both fractions were separated by SDS–PAGE and probed with avidin–alkaline phosphatase to detect biotinylated polypeptides. The cytosolic fraction contained a multifunctional ACCase as indicated by the presence of a biotinylated polypeptide of 200 kDa. The chloroplast stromal fraction contained the 36-kDa biotinylated subunit of the multi-subunit ACCase and a 200-kDa biotinylated protein which suggested the presence of a plastid-localized multifunctional ACCase. Pretreating isolated chloroplasts with thermolysin prior to lysis did not reduce the presence of the 200-kDa biotinylated protein. ACCase activity in both cytosolic and stromal fractions exhibited a high level of tolerance to propaquizafop acid and other graminicides. Total ACCase activity in the chickpea chloroplast stroma fraction appears to be composed of activities contributed by both multisubunit and multifunctional ACCases.

In root nodules of alfalfa (Medicago sativa L.), N2 is reduced to NH4+ in the bacteroid by the nitrogenase enzyme and then released into the plant cytosol. The NH4+ is then assimilated by the combined action of glutamine synthetase (EC 6.3.1.2) and NADH-dependent Glu synthase (NADH-GOGAT; EC 1.4.1.14) into glutamine and Glu. The alfalfa nodule NADH-GOGAT protein has a 101-amino acid presequence, but the subcellular location of the protein is unknown. Using immunocytochemical localization, we determined first that the NADH-GOGAT protein is found throughout the infected cell region of both 19- and 33-d-old nodules. Second, in alfalfa root nodules NADH-GOGAT is localized predominantly to the amyloplast of infected cells. This finding, together with earlier localization and fractionation studies, indicates that in alfalfa the infected cells are the main location for the initial assimilation of fixed N2.

In our search for an endogenous ethylene trigger from tomato (Lycopersicon esculentum Mill. ev. Rutgers) fruit cell wall alkaline soluble pectin (ASP), we purified an active component using DEAE-Sepharose chromatography followed by elution on Bio-Gel P-100 or Superose 12. The purified active fraction produced a single band on silver-stained SDS-PAGE of approximately Mr 20000. Using two-dimensional proton-proton and proton-carbon correlation spectroscopy, we identified the repeating sub-unit as trans-1,2-diamino-cyclohexane- N,N,N′,N′-tetraacetic acid (CDTA), a chelator used to extract ASP. Although the ASP undergoes extensive dialysis during its extraction which should remove CDTA, the CDTA apparently forms a large molecular weight polymer which does not diffuse out of the dialysis tubing. Infiltration of commercially prepared CDTA into mature green tomato fruit stimulated ethylene production. The ethylene stimulatory effect of CDTA was not affected by the presence of equimolar amounts of CaCl2, or nmol g-1 amounts of the calcium channel blockers, nifedipine or verapamil. EDTA, EGTA, and diethylenetriaminepentaacetic acid, other divalent cation chelators, also stimulated ethylene production when they were infiltrated into tomato fruit. Neither the purified material nor commercial CDTA stimulated ethylene production when they were infiltrated into leaf tissue.

A colorimetric method for the determination of total antioxidant activity in a variety of foods and beverages was validated in both a single-laboratory validation and a collaborative laboratory validation study. The procedure involved extraction of the antioxidants directly into a methanol–water solution containing a known amount of 2,2′-diphenyl-1-picrylhydrazyl (DPPH), thus promoting the rapid reaction of extracted materials with DPPH. The reaction was monitored by spectrophotometric measurement of the absorbance loss at 517 nm. Antioxidant activity was quantified relative to a dilution series of vitamin E analog standards (Trolox®), which were analyzed in parallel simultaneously with the food and beverage samples. The antioxidant activities of the samples ranged from 131 to 131 000 μmole Trolox equivalents/100 g. Statistical analysis of the results showed that nine of the 11 matrixes gave acceptable HorRat values, indicating that the method performed well in these cases. The acceptable matrixes include pomegranate juice, blueberry juice, carrot juice, green tea, wine, rosemary spice, ready-to-eat cereal, and yogurt. Two samples failed the HorRat test: the first was an almond milk that had an antioxidant level below the practical LOQ for the method; the second was a sample of canola oil with added omega-3 fatty acid that was immiscible in the reaction medium.

Blood indicators of eight vitamins (, , , C, E, A, B,12 folate) and six minerals (Cu, Mg, Zn, Ca, P, Al) were measured in 86 athletes before and after a 7- to 8-month period of training. During this period half consumed a multivitamin/mineral supplement and a matched group look a placebo, Following the supplementation period, Mood biochemical indicators of , , , and folate status all increased but there were no significant effects of supplementation on , C, E, and A, or on the blood levels of any of the minerals. The supplementation had no effect on red or while cell counts or on hemoglobin levels. Irrespective of the supplementation, some blood measures varied according to sex, females evidencing significantly higher values than males for vitamins C, E, copper, magnesium, and aluminum, with being higher in males. It is concluded that 7 to 8 months of multivitamin/mineral supplementation increased the blood nutritional status of some vitamins but did not affect any blood mineral levels, and that some blood nutritional indicators may vary according to sex.

This systematic review assesses the effectiveness of ventral rectopexy (VR) surgery for treatment of rectal prolapse (RP) and rectal intussusception (RI) in adults. Method MEDLINE, EMBASE, Scopus and other relevant databases were searched to identify studies. Randomized controlled trials or nonrandomized studies with more than 10 patients receiving ventral mesh rectopexy surgery were considered for the review.Twelve nonrandomized case series studies with 728 patients in total are included in the review. Seven studies used the Orr-Loygue procedure (VR with posterior rectal mobilization to the pelvic floor) and five studies used VR without posterior rectal mobilization. Overall weighted mean percentage decrease in faecal incontinence (FI) rate was 45%. The weighted mean percentage decrease in constipation rate was 24%. Weighted mean recurrence rate was 3.4%.There are limitations in published literature on VR. The available data indicate that VR has low recurrence and improves FI in patients suffering from these conditions. There is a greater reduction in postoperative constipation if VR is used without posterior rectal mobilization.

Tailoring the electronic properties of single-walled carbon nanotubes by chemical modification through incorporation of heteroatoms within the tube walls represents a key method for the applicability of these structures in semiconductor technology. For p-type doping experimental studies on the synthesis of B doped single-walled carbon nanotubes have been reported using substitution reactions, arc discharge and laser ablation. However, synthesis using the up-scalability of the widely used chemical vapor deposition approach has not been successful so far. In this work, we present an enhanced CVD approach using high vacuum and promoting the use of solely one liquid precursor containing B and C to synthesize B-doped single walled nanotubes with unique characteristics on the subject of controlled “low doping”. In comparison to non-doped single-walled carbon nanotubes, these tubes have exceptional stability. From Raman and TEM we observe a very low defect concentration concomitant with small nanotube bundles containing 3 to 5 tubes with a narrow diameter distribution (0.9 to 1.5 nm). The defect concentration is significantly lower than in pure carbon nanotube reference samples. The overall B content and the bonding environment of the incorporated B were probed in detail for the first time by XPS. We identified different B bonding environments at less than 1 at%. This highlights the applicability of a rigid band model improving the accessibility of these tubes with controlled p-type doping in nano- and optoelectronic devices.

A review is presented on the application of Raman scattering for the analysis of single wall carbon nanotubes. The Raman response from the tubes is discussed for different tube diameters and for different energies of the exciting laser. It is demonstrated, that the radial breathing mode is particularly useful since it exhibits a very strong photo-selective resonance scattering. The well known fine structure of this mode is demonstrated to be due to a clustering of the frequencies for all geometrically allowed tubes. From a quantitative analysis of the peak positions and of the first moments of the line pattern obtained for excitation with 27 different laser lines the ππ-overlap integral and the lifetime of the excited electronic state were determined to be 3.025 eV and 0.2 ps, respectively. From this fit also the contribution of the tube-tube interaction within the bundles to the frequency of the radial breathing mode was determined. The result was 7% for the set of tubes with larger diameter and 6% for the set of tubes with smaller diameter.

Adult-type hypolactasia, as mediated by a widespread genetic predisposition, not only reduces calcium intake but also calcium absorption in the presence of high amounts of lactose and may, therefore, promote osteoporosis. A lactose-reduced diet and lactose-free calcium supplements may reverse this imbalance.Adult-type hypolactasia (HL) defined by the LCT(-13910) polymorphism may reduce calcium intake by reducing dairy consumption and, therefore, promote osteoporosis. This study aimed to evaluate whether lactose also decreases intestinal calcium absorption in subjects with HL and whether lactose-reduced diet and lactose-free calcium supplementation as recommended could maintain bone mineral density (BMD).Based on LCT genotyping, 73 postmenopausal women with and without HL underwent a conventional H(2) breath test with a concomitant oral strontium absorption test lasting 150 minutes, which closely reflects intestinal calcium absorption. In addition, we compared bone-specific laboratory parameters, lumbar and femoral BMD, and spinal radiographs to a similar bone assessment 5 years earlier.LCT genotyping and functional lactose malabsorption tests were highly correlated. Dairy product consumption was reduced by 80% in HL individuals. During concomitant lactose application, mean strontium absorption was blunted by 54% in HL subjects after 150 minutes (1272 +/- 629 microg/L vs. 2020 +/- 1130 microg/L in lactose tolerant subjects, p=0.001). Nevertheless, BMD in HL subjects remained stable with lactose-free calcium supplements during the observation period.Both decreased calcium intake as well as lactose-associated impaired calcium absorption may predispose subjects with HL to osteoporosis. Lactose-free calcium supplementation may help to maintain BMD in HL subjects.

Summary To more fully characterize the internal structure of transgene loci and to gain further understanding of mechanisms of transgene locus formation, we sequenced more than 160 kb of complex transgene loci in two unrelated transgenic oat (Avena sativa L.) lines transformed using microprojectile bombardment. The transgene locus sequences from both lines exhibited extreme scrambling of non-contiguous transgene and genomic fragments recombined via illegitimate recombination. A perfect direct repeat of the delivered DNA, and inverted and imperfect direct repeats were detected in the same transgene locus indicating that homologous recombination and synthesis-dependent mechanism(s), respectively, were also involved in transgene locus rearrangement. The most unexpected result was the small size of the fragments of deliv- ered and genomic DNA incorporated into the transgene loci via illegitimate recombination; 50 of the 82 delivered DNA fragments were shorter than 200 bp. Eleven transgene and genomic fragments were shorter than the DNA lengths required for Ku-mediated non-homologous end joining. Detection of these small fragments provided evidence that illegitimate recombination was most likely mediated by a synthesis- dependent strand-annealing mechanism that resulted in transgene scrambling. Taken together, these results indicate that transgene locus formation involves the concerted action of several DNA break-repair mechanisms.

Recently, it was possible to fill single wall carbon nanotubes with C60 fullerenes resulting in carbon structures with new and interesting properties (so‐called C60 peapods). All Raman allowed modes of the free C60 were identified for the encaged C60. In this contribution we demosntrate how the concentration of the peas in the SWCNT pods can be obtained from a detailed analysis of the Raman spectra of the peapods.

Measurements on the temperature dependency were carried out for Raman spectra of the radial breathing mode (RBM) of single‐walled carbon nanotubes (SWCNT) in the range between 200 K and 700 K. The observed shifts in lines could be compensated by varying the energy of the exciting laser. The changes are assumed to originate from the temperature dependence of the carbon π‐overlap integral γ0 and the factor of proportionality between RBM frequency and inverse tube diameter C1. The results can be reproduced within a tight‐binding calculation and thus allow to determine the relevant temperature coefficients

Multi-subunit acetyl-coenzyme A carboxylase (MS-ACCase; EC 6.4.1.2) isolated from soybean chloroplasts is a labile enzyme that loses activity during purification. We found that incubating the chloroplast stromal fraction under anaerobic conditions or in the presence of 5 mM FeSO4 stimulated ACCase (acetyl-CoA-->malonyl-CoA) and carboxyltransferase (malonyl-CoA-->acetyl-CoA) activity. Fe-stimulation of activity was associated with 59Fe binding to a stromal protein fraction. ACCase and carboxyltransferase activities measured in the stromal protein fraction containing bound 59Fe were 2-fold and 6-fold greater, respectively, than the control (stromal fraction not pretreated with FeSO4). Superose 6 gel filtration chromatography indicated 59Fe comigrated with stromal protein of approximately 180 kDa that exhibited carboxyltransferase activity, but lacked ACCase activity. Anion exchange (Mono-Q) chromatography of the Superose 6 fraction yielded a protein peak that was enriched in carboxyltransferase activity and contained protein-bound 59Fe. Denaturing gels of the Mono-Q fraction indicated that the 180-kDa protein was composed of a 56-kDa subunit that was bound by an antibody raised against a synthetic beta-carboxyltransferase (beta-CTase) peptide. Incubation of the Mono-Q carboxyltransferase fraction with increasing concentrations of iron at a fixed substrate concentration resulted in increased initial velocities that fit well to a single rectangular three parameter hyperbola (v=vo+Vmax[FeSO4]/Km+[FeSO4]) consistent with iron functioning as a bound activator of catalysis. UV/Vis spectroscopy of the partially purified fraction before and after iron incubation yielded spectra consistent with a protein-bound metal cluster. These results suggest that the beta-CTase subunit of MS-ACCase in soybean chloroplasts is an iron-containing enzyme, which may in part explain its labile nature.

Raman scattering of the radial breathing mode of single wall carbon nanotubes was measured with a large number of different laser lines. The first and the second moments of the spectral distribution were evaluated for all recorded spectra and were found to exhibit damped oscillations with the excitation energy. The oscillations originate from the confinement of the electrons into states distributed within the van Hove singularities. An extended as well as an approximate calculation of the moments yields very good agreement with the experiments and allows to determine the diameter of the nanotube bundles. Using the approximate calculation the mean diameter and the width of the diameter distribution can be evaluated from a single Raman experiment.

Conditional on the fabrication process, SWCNTs appear mostly as bundles of varying diameters. In this paper, the resulting distributions of bundle diameters, determined by Raman spectroscopy and by AFM tapping mode are compared directly.

The stability of the azafullerenes of the type (C59N)X was studied by using infrared, optical and Raman experiments. X represents either hydrogen or an other cage of C59N. The solid phase of the dimer was shown to be stable up to 650 K followed by very slow degradation extending beyond 700 K. This is compared to our very latest results on the temperature stability of C59HN which was found to be stable only up to 540 K. A sudden change in the spectra at this temperature gives evidence for a transition to a new air stable phase which is claimed to be monomeric C59N. When heated in vacuum to about 700 K this phase dimerizes into (C59N)2.

The stability of the azafullerenes of the type (C59N)X was studied by using IR, mass spectroscopy, optical and Raman experiments. X represents either hydrogen or an other cage of C59N. Experimental data indicate thermal stability of the solid phase of the dimer up to 600 K followed by very slow degradation extending beyond 700 K. This is compared to our latest results on the temperature stability of C59HN which was found to be stable only up to 540 K. A sudden change in the spectra at this temperature gives evidence for a transition to a new air stable phase. Since the mass spectra show no loss of hydrogen the new phase is claimed to be polymerized C59HN. When heated in vacuum to about 700 K this phase dimerizes into (C59N)2.

A review is presented on optical and Raman characterization of carbon nanostructures. Particular attention is paid to the new phases of carbon such as fullerenes, poly-fullerenes and carbon nanotubes. For the case of the polyfullerenes the two isostructural dimeres (C59N)2 and (C60)2 are discussed in detail. Both structures exhibit a very strong resonance for red laser excitation of the radial modes. The frequency of the radial breathing mode of single wall carbon nanotubes is shown to exhibit an oscillating behavior as a function of the excitation energy. A quantitative analysis performed for a quasi-continuous distribution of diameters revealed 2.9 eV as the best value for the π-overlap γ0 and an 8% up shift of the mode due to the tube-tube interaction in the bundle.

We report on the vibronic structure of the single bonded charged fullerene dimers (C59N)2 and (C60−)2 in comparison to pristine C60. Raman spectra of (C60−)2 were measured and compared to spectra from (C59N)2 and C60. Observation and analysis concentrates on the low energy modes. Both dimers exhibit a dramatic resonance below 800 cm−1 for red laser excitation. Intercage modes were only observed for the dimers. Their response was lost at the transformation of (C60−)2 to the polymer.

In this contribution we present resent results on the phases of in situ rubidium intercalated C59N. Using Raman spectroscopy six distinct phases were identified by using the charge versus frequency relation of the Ag pinch mode. From additional in situ resistance measurements we find that all phases are semiconducting. Similar to RbxC60 the phase Rb3C59N has the minimum resistance.

Photoselective resonance Raman scattering from laser ablation grown carbon nanotubes is presented. The resonance excitation was found to exhibit a quasi-oscillatory behavior. Assuming a Gaussian distribution of diameters we extracted values for a mean diameter and a width of the distribution within a simple model. In a more expensive calculation the contribution from all geometrically allowed tubes in a certain diameter range was considered. To match experiments and calculations, the frequencies obtained from the latter must be upshifted by ≈10 cm−1. This is ascribed to the tube-tube interaction in the carbon nanotube bundles.

Raman spectra of (C59N)2 are presented for various laser lines and for temperatures between 300 K and 620 K. The material exhibits a reliable stability versus laser illumination for the full temperature range and a remarkable resonance enhancement of the cross section for red light excitation. The Raman intensity versus the used laserpower shows a linear dependence in the entire region observed. The spectra show a strong relation to those of C60, particularly in the spectral range of the tangential modes. Calculations of the mode frequencies with the semiempirical AM1 technique reveal good agreement with the observed Raman lines, in particular for the intermolecular modes observed at 82, 103 and 111 cm−1.

The radial breathing mode around 190 cm -1 was investigated for excitation with 30 different laser lines. It exhibits an oscillatory behaviour with respect to excitation energy. This oscillations could be traced back to the periodicity of the van Hove singularities. Using the first and the second spectral moments parameters characterizing a diameter distribution can be evaluated.