Differences In Relative Amounts Research Articles

Effect of etchant gases on the structure and properties of carbon nanofibers

The utilization of plasma-enhanced chemical vapor deposition (PECVD) for carbon nanofiber (CNF) growth using NH3 as the etchant gas has been extensively documented. Notably, NH3 serves a dual role by etching excess carbon and providing N heteroatoms. Most studies neglect to address this phenomenon, despite the well-known impact of N-doping on CNF properties. Furthermore, NH3 exhibits specific interactions with C2H2—it not only etches excess carbon, but also suppresses the dissociation of C2H2. The implications of this phenomenon on CNF micro- and macroscale morphology have not been comprehensively investigated. To elucidate the influence of etchant gases on CNF structure and properties, we fabricated two types of CNFs - N-doped CNFs (N-CNF) and undoped CNFs (U-CNF). Both were grown on identical substrates using the same carbon source (C2H2) but different etchants (NH3 and H2). Their microstructure and surface chemistry were analyzed using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). Electrochemical properties were investigated using cyclic voltammetry (CV). U-CNFs were found to have a larger population density and a more disordered structure than N-CNFs. N-doping was confirmed in N-CNFs using XPS analysis, which also revealed differences in relative amounts of sp2 C and O functional groups. U-CNFs exhibited distinct electrochemical properties, including smaller pseudocapacitance, larger potential window, slower outer sphere redox (OSR) kinetics, and diminished dopamine sensitivity. Electrochemical differences were rationalized based on CNF structure and surface chemistry, which, in turn, were attributed to how different etchant gases influence the PECVD process.

Effect of spawning induced starvation on nutrient loss in males of the annual spawner Atlantic halibut (Hippoglossus hippoglossus)

Atlantic halibut go through a period with reduced or no feed intake during their spawning period. This study with male Atlantic halibut aimed to assess the effect of a two-month starvation period corresponding to the naturally occurring spawning induced starvation. The actual loss of nutrients compared to initial body burden, was estimated to 25% for gross energy, 32% for total lipid, 14% for crude protein, and 40% and 44% respectively, for the essential fatty acids EPA (C20:5 n-3) and DHA (C22:6 n-3). This indicates that lipid is the preferred energy source during starvation related to spawning, and the n-3 fatty acids are used to a larger extent than other fatty acids, although mono-unsaturated fatty acids (MUFAs) comprised the largest energy reserve. The difference in relative amount of energy and nutrients used should be considered when formulating diets for re-feeding broodstock of annual spawners like the Atlantic halibut.

Analytical approaches for the characterization of early synthetic organic pigments for artists’ paints

Several analytical techniques have shown use for the identification of historical synthetic organic pigments (SOPs) in samples. However, as the techniques differ—for example, in the extent of sample intervention, modes of detection, and limits of detection—so do they differ in results and insights into the colorants and colorant derivatives in a sample. Liquid chromatography (LC) is infrequently applied to the task of SOP identification, despite its ability to differentiate similar molecules, detect at low concentrations, and separate of complex samples and its established usage for organic dyes. This research compared results obtained with micro-Raman spectroscopy and pyrolysis gas chromatography with results from ultra-high performance (UP)LC coupled with photodiode array detection (UPLC-PDA), and high resolution mass spectrometry (UPLC-HRMS) to judge the quantity and quality of SOP information obtained by each technique.In this study, 67 historical samples were analyzed from historical samples and sample books (1918–1950), consisting of 10 oil paint tubes, 45 oil-bound paint-outs, and 13 gum-bound pigment washes using sample sizes less than a milligram. As few studies have used LC for SOP identification, special attention is also paid to issues around sample preparation and interpretation of results from UPLC-PDA and UPLC-PDA-HRMS results. Finally, archival sources and other contemporary documents are used to contextualize and evaluate the plausibility of the analytical results. The results indicate that specific combinations of analytical techniques are required for confident SOP identifications. While Raman results were accurate and independent of sample solubility, they relied heavily on database completeness and were not sensitive to mixtures or differences in relative amounts of SOPs. UPLC-PDA was an effective complement for these shortcomings, except for a few samples that were insoluble. The use of HRMS was critical for the elucidation of unknown SOPs.

Unveiling substitution preference of chromium ions in sulphoaluminate cement clinker phases

Understanding the doping behaviors of impurity ions in mineralogical compositions is of great significance for optimizing the quality of sulphoaluminate cement (SAC) clinker as well as its performance in engineering utilizations. The key issue is determining the exact existing state of these impurity ions. Here, combined with experiments and density functional theoretical (DFT) simulations, we systematically studied the substitution preference of chromium in the three main composed phases of SAC clinker, i. e, C4A3S̅, C2S and C4AF. The formation energies indicate that Cr ions prefer to enter C4AF by substituting Fe ions followed by incorporating into C4A3S̅ with replacement of S ions. The results from X-ray diffractions of single phase show the successful incorporations of Cr ions into both individual mineral, C4AF and C4A3S̅. The dominant content of C4A3S̅ in SAC clinker is well illustrated from Rietveld refinement. Further proof of the doping preference is from the difference in relative amounts of Cr(III) and Cr(VI) in SAC clinker samples with lower dosages. More in-depth analyses from both electron contributions and bond order-bond length distributions show that the substitution preference follows the “electronic structure matching” principle, which ensures the effective substitution by forming stronger bonds between guest ions and oxygen atoms. The doping preference provides a possibility of controlling the valence state of Cr ions by tuning the mineralogical compositions of SAC clinker, thus is essential in guiding the synthesis of SAC-based materials by utilizing Cr-bearing solid waste.

PERIPHERAL BLOOD LYMPHOCYTES ADENOSINE TRIPHOSPHATE AVAILABILITY AMONG THE RESIDENTS OF THE NORTHERN EUROPEAN RUSSIA

Metabolic pathways participating in adenosine triphosphate (ATP) synthesis play an important role in lymphocytes normal development and functioning. Energetic metabolism has an influence on differentiation, proliferation and fate of lymphocytes. The aim of the study is to define ATP availability of peripheral blood lymphocytes and the level of mitochondrial metabolism regulator sirtuin 3 (SIRT3) in healthy northerners. Methods. 106 volunteers, habitants of Arkhangelsk (76 women and 30 men, 21-63 years old) were surveyed. Amounts of immunocompetent cells with receptors (CD3, CD4, CD8, CD10, CD16, CD71, CD23, CD25, HLA DR, CD95) were determined by indirect immunoperoxidase method, ATP concentration in lymphocytes by bioluminescent method, and additionally SIRT3 (23 volunteers) by enzyme immunoassay. Two groups were selected using "k-means" cluster analysis which differed statistically significantly in all studied parameters. Results. It was found that 78 % of the surveyed participants were in the group where ATP concentration was 0,95 (0,487) mcmol/106 cells, in other group with 22 % participants it was 3,71 (1,319) mcmol/106 cells, р < 0,0001. Difference in relative amounts of particular cell phenotypes was revealed in the mentioned groups: in the group with lower ATP levels the higher was percentage of CD95+, CD23+ and HLA DR cells. In the group with higher ATP levels the higher was percentage of CD3+, CD4+, CD8+, CD71+ cells and shift of CD10/CD95 and CD4/CD23 ratios was also detected in favor of CD10+ и CD4+ cells with high levels of metabolic activity. Difference of ATP levels was omni-directional with SIRT3, regulator of mitochondrial metabolism, level with concentrations 0,15 (0,039) and 0,39 (0,198) pg/106 cells, р = 0,0097. Conclusion. Intersectionality of ATP availability and reactivity of T cells was identified. It appears to be promising to determine the level of ATP for evaluation of lymphocytes functioning.

Age-Associated Changes in Ca2+-ATPase and Oxidative Damage in Sarcoplasmic Reticulum of Rat Heart

Altered Ca(2+) handling may be responsible for the development of cardiac contractile dysfunctions with advanced age. In the present study, we investigated the roles of oxidative damage to sarcoplasmic reticulum (SR) and expression of Ca(2+)-ATPase (SERCA 2a) and phospholamban in age-associated dysfunction of cardiac SR. SR vesicles were prepared from hearts of 2-, 6-, 15-, and 26-month-old Wistar rats. Although activity of Ca(2+)-ATPase decreased with advancing age, no differences in relative amounts of SERCA 2a and phospholamban protein were observed. On the other hand, significant accumulation of protein oxidative damage occurred with aging. The results of this study suggest that age-related alteration in Ca(2+)-ATPase activity in the rat heart is not a consequence of decreased protein levels of SERCA 2a and phospholamban, but could arise from oxidative modifications of SR proteins. Cellular oxidative damage caused by reactive oxygen species could contribute to age-related alternations in myocardial relaxation.

Expression of 14-3-3 protein isoforms in mouse oocytes, eggs and ovarian follicular development

BackgroundThe 14-3-3 (YWHA) proteins are a highly conserved, ubiquitously expressed family of proteins. Seven mammalian isoforms of 14-3-3 are known (β, γ, ε, ζ, η, τ and, σ). These proteins associate with many intracellular proteins involved in a variety of cellular processes including regulation of the cell cycle, metabolism and protein trafficking. We are particularly interested in the role of 14-3-3 in meiosis in mammalian eggs and the role 14-3-3 proteins may play in ovarian function. Therefore, we examined the expression of 14-3-3 proteins in mouse oocyte and egg extracts by Western blotting after polyacrylamide gel electrophoresis, viewed fixed cells by indirect immunofluorescence, and examined mouse ovarian cells by immunohistochemical staining to study the expression of the different 14-3-3 isoforms.ResultsWe have determined that all of the mammalian 14-3-3 isoforms are expressed in mouse eggs and ovarian follicular cells including oocytes. Immunofluorescence confocal microscopy of isolated oocytes and eggs confirmed the presence of all of the isoforms with characteristic differences in some of their intracellular localizations. For example, some isoforms (β, ε, γ, and ζ) are expressed more prominently in peripheral cytoplasm compared to the germinal vesicles in oocytes, but are uniformly dispersed within eggs. On the other hand, 14-3-3η is diffusely dispersed in the oocyte, but attains a uniform punctate distribution in the egg with marked accumulation in the region of the meiotic spindle apparatus. Immunohistochemical staining detected all isoforms within ovarian follicles, with some similarities as well as notable differences in relative amounts, localizations and patterns of expression in multiple cell types at various stages of follicular development.ConclusionsWe found that mouse oocytes, eggs and follicular cells within the ovary express all seven isoforms of the 14-3-3 protein. Examination of the differential expression of these 14-3-3 isoforms in female germ cells and ovarian follicles provides the foundation for further investigating 14-3-3 isoform-specific interactions with key proteins involved in ovarian development, meiosis and oocyte maturation. This will lead to a better understanding of the individual functional roles of the 14-3-3 protein isoforms in mammalian oogenesis and female reproductive development.

Local electrostatic charging differences of sub‐100 nm nanocrystalline diamond films

AbstractNanocrystalline diamond (NCD) thin films are deposited on p‐type Si substrates at different deposition temperatures (600–820 °C) in thicknesses below 100 nm. The films are then terminated by oxygen using r.f. oxygen plasma. Atomic force microscopy (AFM) is used to induce electrostatically charged micrometer‐sized patterns on the diamond films by applying a bias voltage on the AFM tip during a contact mode scan. Trapped charge is detected by Kelvin force microscopy, showing potential shifts different in geometry and amplitude on each film for the same absolute bias voltages. The films have similar structure and grain size, measured by AFM and scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) in reflection regime shows the solidity of the films. Material differences are resolved via micro‐Raman spectroscopy. Different charging properties are thus attributed to the differences in relative amount of diamond and sp2 phase.

The Endoplasmic Reticulum Protein Orm2 is Required for Cold Adaptation in Saccharomyces cerevisiae

Despite the fact that wild yeast are known to grow under a wide range of environmental conditions, relatively little is known about mechanisms of cold adaptation. We have found that an endoplasmic reticulum‐resident protein Orm2 is required for cold adaptation in yeast as evidenced by poor growth of the deletion mutant orm2Δ at 10 degrees Celsius. In contrast, the homologous protein Orm1 is not required for cold adaptation. To elucidate the role of Orm2 in cold adaptation, we compared the sensitivity of orm2Δ and wild‐type cells to the anti‐fungal drug amphotericin B and found that orm2Δ cells are more sensitive to the drug at 10 degrees, but not at 30 degrees. orm2Δ mutants also displayed differences in relative amounts of the membrane components ergosterol and squalene as compared to wild‐type at 10 degrees, but not at 30 degrees. Taken together, these results suggest a role for Orm2 as a temperature‐sensitive regulator of the sterol biosynthetic pathway.

Flow cytometric characterization of freshly isolated and culture expanded human synovial cell populations in patients with chronic arthritis

IntroductionThe synovium is a major target tissue in chronic arthritis and is intensively studied at the cellular and molecular level. The aim of this study was to develop flow cytometry for the quantitative analysis of synovial cell populations pre and post culture and to characterize mesenchymal cell populations residing in the inflammatory synovium.MethodsKnee synovium biopsies from 39 patients with chronic arthritis and from 15 controls were treated in a short, standardized tissue digestion procedure. Stored, thawed digests were routinely analyzed with flow cytometry including live-dead staining and use of the markers CD45, CD3, CD14, CD20, CD34, CD73, CD105, CD90, CD146, CD163 and HLA-DR to distinguish inflammatory and stromal cells. The influence of the digestion method on the detection of the different surface markers was studied separately. In addition, we studied the presence of a specific cell population hypothesized to be mesenchymal stem cells (MSC) based on the CD271 marker. Cell expansion cultures were set up and a MSC-related surface marker profile in passages 3 and 6 was obtained. Immunohistochemistry for CD34 and von Willebrand factor (vWF) was done to obtain additional data on synovium vascularity.ResultsThe cell yield and viability normalized to tissue weight were significantly higher in inflammatory arthritis than in controls. Within the hematopoietic CD45-positive populations, we found no differences in relative amounts of macrophages, T-lymphocytes and B-lymphocytes between patient groups. Within the CD45-negative cells, more CD34-positive cells were seen in controls than in arthritis patients. In arthritis samples, a small CD271 positive population was detected. Culture expanded cells were found to fulfill the multipotent mesenchymal stromal cell marker profile, except for CD34 negativity. Detection of peripheral blood macrophage and B-cell markers was decreased after enzymatic exposure and mechanical forces, respectively, but stromal markers were not affected.ConclusionsFlow cytometry can distinguish synovial cell populations in tissue digests. The preparation method can influence the detection levels of macrophage and B-cell populations. However, stromal cell markers seem not affected and quantification is possible, supporting flow cytometry tissue analysis as a tool to study these cell populations in arthritis.

Prevalence of cystic echinococcosis in pigs from Slovakia, with evaluation of size, fertility and number of hydatid cysts

Abstract The regional occurrence of cystic echinococcosis in slaughtered pig from Slovakia was studied in the period of 2000–2008, along with the quantitative parameters associated with the establishment of cysts (intensity of infection, fertility, size). From 103 pig livers collected from abattoirs in 35 sites Slovakia as suspected for Echinococcus infection, 63 were positive for cystic echinococcosis, whereas in 40 livers cysticercosis was diagnosed. Fertile cysts with echinococcal protoscoleces were recorded in 25.4 % of positive pigs, with the 8.9 % fertility rate and the intensity of infection reaching value of 5.9 cysts per liver. The average size of fertile cysts was more than three times larger than diameter of sterile cysts (diameters of 4.67 cm vs. 1.37 cm, respectively). No significant differences in relative amounts of fertile and sterile cysts were found among counties (P = 0.15). The annual prevalence of E. granulosus in pigs in 2000–2 008 has ranged from 0.02 % to 0.13 % (average rate 0.08 %), with the decreasing tendency over the period, especially after 2005. The most heavily affected areas with cystic echinococcosis over 2006–2008 were indicated in Prešov (eastern Slovakia, 0.68 % prevalence) and Komárno districts (southwestern Slovakia, 0.26 % prevalence). Obtained data are relevant in designing regional control strategies to suppress the occurrence of disease in livestock and risk for humans to be infected.

Influence on bionomics of endothelial progenitor cells labeling with magnetic nanoparticles

Objective To explore the influence of home synthesize magnetic iron oxide (called Fe2O3-PLL) labeling on peripheral blood endothelial progenitor cells (EPCs) bionomics to provide experimental foundation for MR imaging ex and in vivo. Methods Fe2O3 was incubated with PLL for 2 hours to obtain a complex of Fe2O3-PLL. Rabbit peripheral blood mononuclear cells were isolated and EPCs were selected by adherence method. Fe2O3-PLL was used to label EPCs. Prussian blue stain and electron microscope was used for showing intracellular iron. MTT assay was assessed to evaluate the difference of growth curve between unlabeled and labeled with 25 mg/L Fe2O3-PLL. Flow cytometry was performed to analyze cell cycle, cell apoptosis and the expression of surface markers of labeled and unlabeled cells. Expressions of Enos, KDR and Vwf at Mrna levels among unlabeled and labeled EPCs were detected by real-time polymerase chain reaction. Calcium ion channel and membrane fluidity were observed and analyzed by laser confocal microscopy. Statistical analyses were used with ANOVA and t test. Results Almost 100% cells were labeled by Fe2O3-PLL, iron-containing vesicles were intracytoplasma. There was no statistical difference in cells growth curve, cell life cycle [(93.74±3.52)% ,(94.57±3.66)% ] and cell apoptosis rate(12. 89±1.81) %, (11.67±1.18) %) between labeling with Fe2O3-PLL at a concentration of 25 mg/L and unlabeled cells (t = 0. 283, P > O. 05 ; t = 0. 977, P > 0. 05). There was also no statistical difference in relative amount of Enos, KDR and Vwf at Mrna levels and the expression of sudace phenotypic markers (CD34, CD106, CD146 and KDR) between two groups (P > 0. 05). In addition,Labeling had little influence on calcium ion channel and didn't significantly alter cell membrane fluidity.Conclusions The rabbit peripberal blood EPCs can be effective labeled with Fe2O3-PLL and without significant influence on cells bionomics at a low concentration of 25 mg/L. Almost every cell can be labeled and the labeled cells can be used further. Key words: Nanoparticles; Ironchelating agents; Stem cells; Immuneenzyme techniques; Animals, laboratory

Principal component analysis for the comparison of metabolic profiles from human rectal cancer biopsies and colorectal xenografts using high-resolution magic angle spinning 1H magnetic resonance spectroscopy

BackgroundThis study was conducted in order to elucidate metabolic differences between human rectal cancer biopsies and colorectal HT29, HCT116 and SW620 xenografts by using high-resolution magnetic angle spinning (MAS) magnetic resonance spectroscopy (MRS) and for determination of the most appropriate human rectal xenograft model for preclinical MR spectroscopy studies. A further aim was to investigate metabolic changes following irradiation of HT29 xenografts.MethodsHR MAS MRS of tissue samples from xenografts and rectal biopsies were obtained with a Bruker Avance DRX600 spectrometer and analyzed using principal component analysis (PCA) and partial least square (PLS) regression analysis.Results and conclusionHR MAS MRS enabled assignment of 27 metabolites. Score plots from PCA of spin-echo and single-pulse spectra revealed separate clusters of the different xenografts and rectal biopsies, reflecting underlying differences in metabolite composition. The loading profile indicated that clustering was mainly based on differences in relative amounts of lipids, lactate and choline-containing compounds, with HT29 exhibiting the metabolic profile most similar to human rectal cancers tissue. Due to high necrotic fractions in the HT29 xenografts, radiation-induced changes were not detected when comparing spectra from untreated and irradiated HT29 xenografts. However, PLS calibration relating spectral data to the necrotic fraction revealed a significant correlation, indicating that necrotic fraction can be assessed from the MR spectra.

HPLC–NMR with severe column overloading: Fast-track metabolite identification in urine and bile samples from rat and dog treated with [ 14C]-ZD6126

The subject of this study was the determination of the major urinary and biliary metabolites of [ 14C]-ZD6126 following i.v. administration to female and male bile duct cannulated rats at 10 mg/kg and 20 mg/kg, respectively, and male bile duct cannulated dogs at 6 mg/kg by HPLC–NMR spectroscopy. ZD6126 is a phosphorylated pro-drug, which is rapidly hydrolysed to the active metabolite, ZD6126 phenol. The results presented here demonstrate that [ 14C]-ZD6126 phenol is subsequently metabolised extensively by male dogs and both, male and female rats. Recovery of the dose in bile and urine was determined utilising the radiolabel, revealing biliary excretion as the major route of excretion (93%) in dog, with the majority of the radioactivity recovered in both biofluids in the first 6 h. In the rat, greater than 92% recovery was obtained within the first 24 h. The major route of excretion was via the bile 51–93% within the first 12 h. The administered phosphorylated pro-drug was not observed in any of the excreta samples. Metabolite profiles of bile and urine samples were determined by high performance liquid chromatography with radiochemical detection (HPLC–RAD), which revealed a number of radiolabelled components in each of the biofluids. The individual metabolites were subsequently identified by HPLC–NMR spectroscopy and HPLC–MS. In the male dog, the major component in urine and bile was the [ 14C]-ZD6126 phenol glucuronide, which accounted for 3% and 77% of the dose, respectively. [ 14C]-ZD6126 phenol was observed in urine at 1% of dose, but was not observed in bile. A sulphate conjugate of demethylated [ 14C]-ZD6126 phenol was identified in bile by HPLC–NMR and confirmed by HPLC–MS. In the rat, the bile contained two major radiolabelled components. One was identified as the [ 14C]-ZD6126 phenol glucuronide, the other as a glucuronide conjugate of demethylated [ 14C]-ZD6126 phenol. However, a marked difference in the proportions of these two components was observed between male and female rats, either due to a sex difference in metabolism or a difference in dose level. The glucuronide conjugate of the demethylated [ 14C]-ZD6126 phenol was present at higher concentration in the bile of male rats (4–34%), while the phenol glucuronide was present at higher concentration in the bile of female rats (8–70%) over a 0–6 h collection period. A third component was only observed in the bile samples (0–6 h and 6–12 h) of male rats. This was identified as being the same sulphate conjugate of demethylated [ 14C]-ZD6126 phenol as the one observed in dog bile. The rat urines contained two main metabolites in greatly varying concentrations, namely the demethylated [ 14C]-ZD6126 phenol glucuronide and the glucuronide of [ 14C]-ZD6126 phenol. Again, the differences in relative amounts between male and female rats were observed, the major metabolite in the urines from male rats being the demethylated [ 14C]-ZD6126 phenol (0–17% in 0–24 h), whilst the phenol glucuronide, accounting for 0.5–50% of the dose over 0–24 h, was the major metabolite in females. Methanolic extracts of the pooled biofluid samples were submitted for HPLC–NMR for the quick identification of the major metabolites. Following a single injection of the equivalent of 6–28 ml of the biofluids directly onto the HPLC-column with minimal sample preparation, the metabolites could be largely successfully isolated. Despite severe column overloading, the major metabolites of [ 14C]-ZD6126 could be positively identified, and the results are presented in this paper.

Reduced Replication: A Call to ARMS

In this issue of Cell, Lemoine et al. monitor chromosome instability in yeast cells with reduced levels of an essential replicative DNA polymerase. The authors identify a hotspot for chromosome aberrations reminiscent of fragile sites in human cells. This hotspot is composed of inverted Ty elements, which lead to a double-strand break under conditions of limited replication.

Rapid identification of Candida species by using nuclear magnetic resonance spectroscopy and a statistical classification strategy.

Nuclear magnetic resonance (NMR) spectra were acquired from suspensions of clinically important yeast species of the genus Candida to characterize the relationship between metabolite profiles and species identification. Major metabolites were identified by using two-dimensional correlation NMR spectroscopy. One-dimensional proton NMR spectra were analyzed by using a staged statistical classification strategy. Analysis of NMR spectra from 442 isolates of Candida albicans, C. glabrata, C. krusei, C. parapsilosis, and C. tropicalis resulted in rapid, accurate identification when compared with conventional and DNA-based identification. Spectral regions used for the classification of the five yeast species revealed species-specific differences in relative amounts of lipids, trehalose, polyols, and other metabolites. Isolates of C. parapsilosis and C. glabrata with unusual PCR fingerprinting patterns also generated atypical NMR spectra, suggesting the possibility of intraspecies discontinuity. We conclude that NMR spectroscopy combined with a statistical classification strategy is a rapid, nondestructive, and potentially valuable method for identification and chemotaxonomic characterization that may be broadly applicable to fungi and other microorganisms.

Do changes in floral odor cause speciation in sexually deceptive orchids

We investigated differences in floral odor between two sympatric, closely related sexually deceptive orchid species, Ophrys fusca and O. bilunulata, which are specifically pollinated by Andrena nigroaenea and A. flavipes, respectively. We identified biologically active compounds by gas chromatography with electroantennographic detection using antennae of the pollinator bees. Alkanes, alkenes, aldehydes, and farnesyl hexanoate released electroantennographic reactions. The relative amounts of alkanes were mostly the same between the two orchid species, whereas the relative amounts of most alkenes were significantly different. On the grounds of these findings and behavioral experiments conducted in earlier studies, we suggest that the difference in relative amounts of alkenes is responsible for the selective attraction of pollinators in the two orchids. Speciation in this group of Ophrys orchids may be brought about by changes in pattern of alkenes, which lead to attraction of a different pollinator species and therefore reproductive isolation.

Immunohistochemical evidence of cytochrome C oxidase subunit II involvement in pulmonary hypertension syndrome (PHS) in broilers

Defects and variation in the relative amount of protein subunits in the mitochondrial electron transport chain (ETC) have been hypothesized to be involved, in part, in the pathogenesis of pulmonary hypertension syndrome (PHS), a costly metabolic disease. Thus, the major objective of this study was to determine whether differences in relative amounts of cytochrome c oxidase subunit I and II (COX I and II) can be detected by immunohistochemistry and digital image analysis in muscle tissue of broilers with PHS compared to control broilers. Cross sections of the breast muscle (pectoralis major) were stained with monoclonal antibodies for COX I and II. Relative areas of multiple microscope viewing fields (400x) per tissue section of COX I and II were quantified by counting immunopositive pixels on the digital images. Whereas the number of immunopositive pixels for COX II was higher in PHS birds compared to controls, there were no difference for COX I. The amount of COX II was positively correlated with the right to total ventricular weight ratio (RV:TV), suggesting that there may be increased expression of COX II associated with severity of pulmonary arterial hypertension. Thus, it is possible that COX II expression in PHS broiler may be involved in the pathogenesis of PHS.

Characterization and developmental expression of single-stranded telomeric DNA-binding proteins from mung bean (Vigna radiata).

We have identified and characterized protein factors from mung bean (Vigna radiata) nuclear extracts that specifically bind the single-stranded G-rich telomeric DNA repeats. Nuclear extracts were prepared from three different types of plant tissue, radicle, hypocotyl, and root, in order to examine changes in the expression patterns of telomere-binding proteins during the development of mung bean. At least three types of specific complexes (A, B, and C) were detected by gel retardation assays with synthetic telomere and nuclear extract from radicle tissue, whereas the two major faster-migrating complexes (A and B) were formed with nuclear extracts from hypocotyl and root tissues. Gel retardation assays also revealed differences in relative amount of each complex forming activity in radicle, hypocotyl, and root nuclear extracts. These data suggest that the expression of telomere-binding proteins is developmentally regulated in plants, and that the factor involved in the formation of complex C may be required during the early stages of development. The binding factors have properties of proteins and are hence designated as mung bean G-rich telomere-binding proteins (MGBP). MGBPs bind DNA substrates with three or more single-stranded TTTAGGG repeats, while none of them show binding affinity to either double-stranded or single-stranded C-rich telomeric DNA. These proteins have a lower affinity to human telomeric sequences than to plant telomeric sequences and do not exhibit a significant binding activity to Tetrahymena telomeric sequence or mutated plant telomeric sequences, indicating that their binding activities are specific to plant telomere. Furthermore, RNase treatment of the nuclear extracts did not affect the complex formation activities. This result indicates that the single-stranded telomere-binding activities may be attributed to a simple protein but not a ribonucleoprotein. The ability of MGBPs to bind specifically the single-stranded TTTAGGG repeats may suggest their in vivo functions in the chromosome ends of plants.

CARBOHYDRATE INTAKE AND MARKERS OF OVERTRAINING

885 Current research indicates that insufficient carbohydrate (CHO) intake may be linked to the etiology of the overtraining syndrome. Furthermore, endurance runners are susceptible to CHO debt due to the high volume of training which they perform at intensities where CHO is the primary energy source. The aim of this study was to elucidate the relationship between CHO intake and overtraining markers. Nine male, cross-country athletes (20.9±3.1 yrs;66.7±5.4kg) were split into supplement (N=4) and placebo (N=5) groups. Blood was drawn at the beginning (B) middle (M) and end (E) of the season with dietary logs being kept during weeks B,M and E. Training logs were recorded weekly. Case II t-Test analysis (N=8;df=6;α=.05) of M data revealed no significant differences between groups for the overtraining markers. Analysis (N=7;df=5;α=.05) found total grams of CHO (p=.010) and total calories (p=.010) to be significantly higher in the supplement group. Grams of CHO per kg (p=.074), % of caloric intake from CHO (df=5;p=.567) and calories per kg (df=5;p=.108) were not significantly different between groups. Correlational analysis revealed the following: (Table)TableEarly findings suggest that CHO supplementation may not result in a significant difference in relative amounts of CHO and calories ingested. However, markers of overtraining appear to be inversely related to CHO and caloric intake. Partially Supported by Gatorade Sports Science Institute