Effect of diets enriched in almonds on insulin action and serum lipids in adults with normal glucose tolerance or type 2 diabetes.
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BACKGROUND: Nuts appear to have cardiovascular benefits but their effect in diabetic patients is unclear. OBJECTIVE: The objective was to assess effects of almond-enriched diets on insulin sensitivity and lipids in patients with normoglycemia or type 2 diabetes. DESIGN: Study 1 assessed the effect of almonds on insulin sensitivity in 20 free-living healthy volunteers who received 100 g almonds/d for 4 wk. Study 2 was a randomized crossover study that compared 4 diets in 30 volunteers with type 2 diabetes: 1) high-fat, high-almond (HFA; 37% total fat, 10% from almonds); 2) low-fat, high-almond (LFA; 25% total fat, 10% from almonds); 3) high-fat control (HFC; 37% total fat, 10% from olive or canola oil); and 4) low-fat control (LFC; 25% total fat, 10% from olive or canola oil). After each 4-wk diet, serum lipids and oral glucose tolerance were measured. RESULTS: In study 1, almond consumption did not change insulin sensitivity significantly, although body weight increased and total and LDL cholesterol decreased by 21% and 29%, respectively (P < 0.05). In study 2, total cholesterol was lowest with the HFA diet (4.46 +/- 0.14, 4.52 +/- 0.14, 4.63 +/- 0.14, and 4.63 +/- 0.14 mmol/L with the HFA, HFC, LFA, and LFC diets, respectively; P = 0.0004 for fat level). HDL cholesterol was significantly lower with the almond diets (P = 0.002); however, no significant effect of fat source on LDL:HDL was observed. Glycemia was unaffected. CONCLUSIONS: Almond-enriched diets do not alter insulin sensitivity in healthy adults or glycemia in patients with diabetes. Almonds had beneficial effects on serum lipids in healthy adults and produced changes similar to high monounsaturated fat oils in diabetic patients. (+info)
Characterization of two putative ethylene receptor genes expressed during peach fruit development and abscission.
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Two peach genes homologous to the Arabidopsis ethylene receptor genes ETR1 and ERS1, named Pp-ETR1 and Pp-ERS1 respectively, have been isolated and characterized. Pp-ETR1 and Pp-ERS1 are conserved in terms of exon numbers and intron positions, although the first and fifth introns of Pp-ETR1 have an unusual length. In addition, two putative polyadenylation sites, that may cause an incomplete splicing at the 3' terminus, are present in the fifth intron. A motif of 28 nt, which shows high homology with ethylene responsive elements found in promoters of genes up-regulated by ethylene, is present in the promoter region of Pp-ERS1. Expression analysis, carried out by quantitative RT-PCR, was performed during fruit development and ripening, and leaf and fruitlet abscission. The level of Pp-ETR1 transcripts remained unchanged in all the tissues and developmental stages examined, whereas Pp-ERS1 mRNA abundance increased in ripening mesocarp, in leaf and fruitlet activated abscission zones, and following propylene application. 1-methylcyclopropene (1-MCP), an inhibitor of ethylene action, did not affect Pp-ETR1 transcription, while it down-regulated Pp-ERS1. A rise in ethylene evolution, accompanied by an increase of Pp-ERS1 transcript accumulation occurred within 24 h from the end of 1-MCP treatment. These results indicate that Pp-ERS1 might play a role in abscission and ripening. (+info)
Contribution of vegetative storage proteins to seasonal nitrogen variations in the young shoots of peach trees (Prunus persica L. Batsch).
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Qualitative and quantitative variations in the level of two low molecular weight vegetative storage proteins (VSP 19 kDa and 16.5 kDa) in peach shoots were compared with annual variations in total nitrogen and total soluble proteins. Protein patterns were obtained by SDS-PAGE and silver staining on each of the 12 kinetic samples collected between October 1995 and November 1996. VSP 16.5 kDa and 19 kDa exhibited typical annual VSP variations in both parenchyma and phloem. In wood, VSP 16.5 kDa was only present in November. All N compounds tested were stored in the autumn and their levels fell in the spring. Parenchyma was the principal stem storage tissue for all N compounds tested, even if proteins were more often highly concentrated in phloem and even if wood was the major shoot constituent. In winter, the two VSP accounted for 13% of bark proteins and 11% of wood proteins. Their storage yield, given by the winter/summer (W/S) ratio was higher (18.5) than that of total proteins (4). Between August to March, i.e. during the storage phase, N fractions obtained from VSP (N3) and total soluble proteins minus VSP (N2) accounted, respectively, for only 3% and 21% of total N accumulation in the bark, the remainder being due to the fraction not extracted (N1). A marked drop in all N compound levels characterized the mobilization phase (March to April), particularly for N3 (-84% between March and April) which were mobilized slightly before other N compounds. Although N3 exhibited the best mobilization yield, it represented only 5% of the total N mobilized. So, in spite of a similarity between VSP and N annual variation patterns, there was no tight correlation between their contents in bark. N2 supplied a high proportion of the N used for spring regrowth (40%), but the larger share (55%) came from N1 which was probably made up of free amino acids. Very tight positive correlations have been observed between these two N fractions and the N status. The lower bark total N content measured in August (6.4 mg N g(-1 )DW) during the assimilation phase (April to August) was equal to the unavailable N fraction, and the bark N mobilization potential (between March and August) was estimated at 6.35 mg N g(-1) DW. VSP did not quantitatively represent the main stored N pool. But, because of their high W/S ratio and their early remobilization, they seemed to play an important role in spring regrowth initiation. (+info)
Effects of prune consumption on the ratio of 2-hydroxyestrone to 16alpha-hydroxyestrone.
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BACKGROUND: A higher urinary ratio of the biologically inactive estrogen metabolite, 2-hydroxyestrone (2OHE1), to the biologically active metabolite, 16alpha-hydroxyestrone (16alphaOHE1), may be associated with a lower risk of breast cancer. High fiber intake is also associated with decreased breast cancer risk. OBJECTIVE: We investigated the effects of prunes, which are naturally rich in both soluble and insoluble fiber, on the concentrations of 2OHE1 and 16alphaOHE1 and on the ratio of 2OHE1 to 16alphaOHE1. DESIGN: Nineteen healthy premenopausal women consumed their habitual diets for 3 menstrual cycles and then consumed 100 g prunes/d for the next 3 cycles. Concentrations of urinary 2OHE1 and 16alphaOHE1 were determined during the follicular and luteal phases. RESULTS: Prune supplementation increased total and soluble fiber intakes by 4 and 2 g/d, respectively (P < 0.001). Mean (+/- SEM) luteal 2OHE1 excretion decreased from 3.92 +/- 0.79 to 2.20 +/- 0.40 nmol/mmol creatinine during the third cycle (P = 0.017). Luteal 16alphaOHE1 excretion decreased from 1.38 +/- 0.24 to 0.87 +/- 0.10 and 0.87 +/- 0.15 nmol/mmol creatinine during the first and third cycles, respectively (P = 0.018 for both values). Follicular 16alphaOHE1 excretion decreased significantly only during the first cycle (from 0.82 +/- 0.12 to 0.45 +/- 0.09 nmol/mmol creatinine; P = 0.005). The 2OHE1-16alphaOHE1 ratio did not change significantly after prune supplementation. CONCLUSIONS: Prune supplementation significantly decreased the excretion of 16alphaOHE1 during the follicular phase of the first menstrual cycle and during the luteal phases of both the first and third menstrual cycles. The 2OHE1-16alphaOHE1 ratio did not change significantly. The potential significance of the decrease in 16alphaOHE1 excretion, without a change in the 2OHE1-16alphaOHE1 ratio, on the prevention of estrogen-dependent cancers remains to be determined. (+info)
Fusicoccins P and Q, and 3-epifusicoccins H and Q, new polar fusicoccins from isolate Niigata 2-A of a peach Fusicoccum canker fungus.
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Our search for new polar fusicoccins biosynthetically related to fusicoccin A from the culture filtrate of isolate Niigata 2-A of a peach Fusicoccum canker fungus resulted in the isolation of new fusicoccins named fusicoccins P and Q, and 3-epifusicoccins H and Q, together with 3'-deacetylfusicoccin A and 16-O-demethyl-3-epifusicoccin J. The structures of fusicoccins P and Q, and of 3-epifusicoccin Q were determined to be those of deisopentenylfusicoccin J, 12alpha-hydroxyfusicoccin H and 12alpha-hydroxy-3-epifusicoccin H, respectively, by NMR spectrometry and chemical derivation from known fusicoccins. 3-Epifusicoccin H was identified by comparing its 400 MHz NMR spectra with those of fusicoccin H. The lettuce seed germination-stimulating activity of these new fusicoccins was examined in the presence of ABA: fusicoccin P was highly active, while 3-epifusicoccins H and Q were slightly active, and fusicoccins H and Q were almost inactive. Possible biosynthetic pathways incorporating these new fusicoccins and 3-epifusicoccins from geranylgeranyl diphosphate to 3'-deacetlyfusicoccin A and 16-O-demethyl-3-epifusicoccin J are discussed. (+info)
Fungicide sprays can injure the stigmatic surface during receptivity in almond flowers.
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Fungicides can be detrimental to flower development, pollen function and fruit set in a number of crops. Almond is a self-incompatible nut crop that has a fruit set of only approx. 30 % of the total number of flowers. Thus, interference of pollination and fertilization by fungicide sprays is of concern, and identification of chemicals having the least detrimental effects would be desirable. The objective of this study was to evaluate the effect of fungicide sprays on stigma morphology in almond using a laboratory spray apparatus that simulated field applications. Four fungicides (azoxystrobin, myclobutanil, iprodione and cyprodinil) were applied, and fresh, unfixed stigmatic surfaces were observed using a scanning electron microscope at 4 and 24 h after spraying. Increased exudate accumulation was induced by azoxystrobin at both time periods, and localized damage and collapse of stigmatic cells were observed after 24 h. Damaged stigmatic papillae exhibited wrinkling, surface distortion or collapse. Likewise, myclobutanil caused significant damage to and collapse of papillae; these were more extensive at later observations. Iprodione had no effect on exudate accumulation but caused marked and severe collapse of stigmatic papillae which was pronounced at 24 h. Cyprodinil promoted a copious increase in exudate secretion and caused the most severe collapse of stigmatic cells of all the fungicides evaluated. Damage was somewhat localized at 4 h but more global at 24 h. This study has verified that certain fungicide sprays have direct detrimental effects on stigma morphology and enhance exudate production in almond flowers. (+info)
Genetic mapping of the evergrowing gene in peach [Prunus persica (L.) Batsch].
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In temperate locations, terminal apices on evergrowing (also called evergreen) peach trees keep growing in winter until killed by low temperatures, while the lateral buds go into dormancy. A recessive allele of a single gene (evergrowing or evg) controls this trait in peach. The amplified fragment length polymorphism (AFLP) technique and bulked segregant analysis were applied to construct a local genetic linkage map for the evg gene from the cross Empress op op dwarf x Evergrowing (P.I. 442380). This map, comprising nine AFLP markers and the evg locus, covers a total genetic distance of 79.3 cM. Four dominant AFLP markers (EAT/MCAC, ETT/MCCA2, EAT/MCTA, and ETT/MACC) were linked to the evg locus at distances of 1, 5.3, 6.7, and 11.7 cM, respectively. EAT/MCAC and EAT/MCTA were converted into polymorphic sequence-tagged sites. Microsatellite markers in the evg region were developed from peach bacterial artificial chromosome (BAC) clones that hybridized to the AFLP marker fragments. Using three microsatellite anchor markers (pchgms12, pchgms17, and pchgms19), the local genetic linkage map was integrated into one minor linkage group of a previously constructed peach rootstock genetic linkage map. Three AFLP markers from the rootstock genetic linkage map were found linked to the evg locus. (+info)
Anti-tumor promoting effect of glycosides from Prunus persica seeds.
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Four minor components, along with the major cyanogenic glycosides, amygdalin and prunasin, were isolated from Prunus persica seeds (Persicae Semen; Tounin), and characterized as mandelic acid glycosides (beta-gentiobioside and beta-D-glucoside) and benzyl alcohol glycosides (beta-gentiobioside and beta-D-glucoside). The anti-tumor promoting activity of these compounds was examined in both in vitro and in vivo assays. All of the compounds significantly inhibited the Epstein-Barr virus early antigen activation induced by tumor promoter. In addition, they produced a delay of two-stage carcinogenesis on mouse skin that was comparable in potency to (-)-epigallocatechin gallate from green tea. Structure-activity relationships indicated that a substituent at the benzylic position with glycosidic linkage affected the in vitro and in vivo activities with an order of enhancing potency, CN+info)