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1
Downs, Drew T., Michael A. Clynne, Duane E. Champion, and L. J. Patrick Muffler. "Eruption age and duration of the ∼9 km3 Burney Mountain dacite dome complex, northern California, USA." GSA Bulletin 132, no. 5-6 (October 30, 2019): 1150–64. http://dx.doi.org/10.1130/b35240.1.
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Abstract At ∼9 km3, the six dacite domes (db1–db6) of Burney Mountain, northern California, USA, constitute the most voluminous Quaternary dome complex in the Cascades volcanic arc. Whole-rock geochemistry, electron microprobe, and petrographic data indicate that the domes are magmatically related, which when integrated with geomorphology and stratigraphic superposition, indicate early (db1, db2, and db3) and late (db4, db5, and db6) erupted groups. We present 40Ar/39Ar ages of 271.9 ± 4.6 ka (db1), 280.8 ± 8.2 and 281.7 ± 6.8 ka (db2), and 290.2 ± 6.0 ka (db3) along with a previous age of 280 ± 12 ka (db1). These ages scatter over 20 k.y., whereas remanent magnetic directions are similar between 53.3–59.0° inclination and 352.7–355.9° declination. The latter data set indicates that the dacite domes were emplaced over a geologically brief time interval, not thousands of years. Crystal-size distribution patterns of plagioclase were used to calculate residence times, which we use to infer the duration over which the eruptions likely occurred. Three slopes represent three populations of plagioclase crystals (fine-grained groundmass, coarse-grained groundmass, and phenocrysts). A commonly used growth rate for plagioclase in dacitic magmas (10−10 mm/s) yields 9–10 yr of growth for the coarse-grained groundmass (early erupted domes of db1, db2, and db3), whereas plagioclase in the fine-grained groundmass (late erupted domes of db4, db5, and db6) grew over 4–5 yr. All plagioclase phenocrysts have apparent residence times of 26–36 yr; however, they contain high anorthite (An)>70 resorbed cores with sieve textures, which have euhedral, lower An<65 overgrowth rims. Similarities in chemistry between groundmass plagioclase and phenocryst overgrowth rims indicate that they grew concurrently, and we therefore propose that both have similar residence times. Thus, the Burney Mountain dacite dome complex was emplaced during a single eruptive episode over the course of years to decades at 281.1 ± 4.8 ka (weighted mean age).
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Acharya, J., M. G. Bakker, T. B. Moorman, T. C. Kaspar, A. W. Lenssen, and A. E. Robertson. "Time Interval Between Cover Crop Termination and Planting Influences Corn Seedling Disease, Plant Growth, and Yield." Plant Disease 101, no. 4 (April 2017): 591–600. http://dx.doi.org/10.1094/pdis-07-16-0975-re.
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Experiments were established in a controlled-growth chamber and in the field to evaluate the effect of the length of time intervals between winter rye cover crop termination and corn planting on corn seedling disease, corn growth, and grain yield in 2014 and 2015. Rye termination dates ranged from 25 days before planting (DBP) to 2 days after planting (DAP) corn in the field and from 21 DBP to 1 DAP in controlled studies. Results were similar in both environments. In general, shorter intervals increased seedling disease and reduced corn emergence, shoot growth, and grain yield of corn following winter rye compared with corn planted 10 or more days after rye termination or without rye. Incidence of Pythium spp. increased with shorter intervals (less than 8 DBP); incidence of Fusarium spp. was not consistent between runs and experiments. In 2014, in the 1-DAP treatment, number of ears and grain yield were reduced (P = 0.05 and 0.02, respectively). In 2015, all termination intervals reduced plant population, number of ears, and yield (P = 0.01), with the 2-DBP treatment causing the biggest decrease. A 10- to 14-day interval between rye termination and corn planting should be followed to improve corn yield following a rye cover crop.
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Arora, Harish, Mark W. LeChevallier, and Kevin L. Dixon. "DBP occurrence survey." Journal - American Water Works Association 89, no. 6 (June 1997): 60–68. http://dx.doi.org/10.1002/j.1551-8833.1997.tb08242.x.
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Sung, Windsor, Betsy Reilley-Matthews, D. Kelly O'Day, and Kristin Horrigan. "Modeling DBP formation." Journal - American Water Works Association 92, no. 5 (May 2000): 53–63. http://dx.doi.org/10.1002/j.1551-8833.2000.tb08944.x.
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Meyers, Stephen L., Katherine M. Jennings, Donnie K. Miller, and Mark W. Shankle. "Response of sweetpotato to diquat applied pretransplanting." Weed Technology 34, no. 5 (February 17, 2020): 637–41. http://dx.doi.org/10.1017/wet.2020.27.
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AbstractField trials were conducted in North Carolina in 2017 and Louisiana and Mississippi in 2018 to determine the effect of pretransplanting applications of diquat on sweetpotato crop tolerance, yield, and storage root quality. In North Carolina treatments consisted of two rates of diquat (560 or 1,120 g ai ha−1) alone or mixed with 107 g ai ha−1 flumioxazin and applied 1 d before transplanting (DBP), sequential applications of diquat (560 or 1,120 g ha−1) 1 and 17 DBP, 107 g ha−1 flumioxazin alone, and a nontreated check. In Louisiana and Mississippi treatments consisted of diquat (560 or 1,120 g ha−1) applied 1 DBP either alone or followed by (fb) rehipping rows or 107 g ha−1 flumioxazin immediately prior to transplanting. Additional treatments included 546 g ha−1 paraquat applied 1 DBP and a nontreated check. In North Carolina injury was ≤3% for all treatments through 23 d after transplanting (DAP), and no injury was observed after 23 DAP. Visual sweetpotato stunting pooled across the Mississippi and Louisiana trials ranged from 1% to 14%, 0% to 6%, and 0% to 3% at 2, 4, and 6 wk after planting (WAP), respectively, and no crop injury was observed after 6 WAP. Diquat applied 1 DBP and not fb rehipping resulted in greater crop injury (12%) than comparable treatments that were rehipped (2%). In North Carolina single and sequential diquat applications resulted in reduced No. 1 sweetpotato yield (24,230 and 24,280 kg ha−1, respectively) compared with the nontreated check, but No. 1 yield when diquat plus flumioxazin (26,330 kg ha−1) was used was similar to that of the nontreated check. No. 1 yield did not differ by treatment in Louisiana and Mississippi.
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Ganguly, Ankana, Jennifer A. Tamblyn, Alexandra Shattock, Annsha Joseph, Dean P. Larner, Carl Jenkinson, Janesh Gupta, Stephane R. Gross, and Martin Hewison. "Trophoblast uptake of DBP regulates intracellular actin and promotes matrix invasion." Journal of Endocrinology 249, no. 1 (April 2021): 43–55. http://dx.doi.org/10.1530/joe-20-0626.
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Early pregnancy is characterised by elevated circulating levels of vitamin D binding protein (DBP). The impact of this on maternal and fetal health is unclear but DBP is present in the placenta, and DBP gene variants have been linked to malplacentation disorders such as preeclampsia. The functional role of DBP in the placenta was investigated using trophoblastic JEG3, BeWo and HTR8 cells. All three cell lines showed intracellular DBP with increased expression and nuclear localisation of DBP in cells treated with the active form of vitamin D, 1,25-dihydroxyvitamin D (1,25D). When cultured in the serum of mice lacking DBP (DBP−/−), JEG3 cells showed no intracellular DBP indicating uptake of exogenous DBP. Inhibition of the membrane receptor for DBP, megalin, also suppressed intracellular DBP. Elimination of intracellular DBP with DBP−/− serum or megalin inhibitor suppressed matrix invasion by trophoblast cells and was associated with increased nuclear accumulation of G-actin. Conversely, treatment with 1,25D enhanced matrix invasion. This was independent of the nuclear vitamin D receptor but was associated with enhanced ERK phosphorylation, and inhibition of ERK kinase suppressed trophoblast matrix invasion. When cultured with serum from pregnant women, trophoblast matrix invasion correlated with DBP concentration, and DBP was lower in first-trimester serum from women who later developed preeclampsia. These data show that the trophoblast matrix invasion involves uptake of serum DBP and associated intracellular actin-binding and homeostasis. DBP is a potential marker of placentation disorders such as preeclampsia and may also provide a therapeutic option for improved placenta and pregnancy health.
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Raju, U. S. N., K. Suresh Kumar, Pulkesh Haran, Ramya Sree Boppana, and Niraj Kumar. "Content-based image retrieval using local texture features in distributed environment." International Journal of Wavelets, Multiresolution and Information Processing 18, no. 01 (March 5, 2019): 1941001. http://dx.doi.org/10.1142/s0219691319410017.
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In this paper, we propose novel content-based image retrieval (CBIR) algorithms using Local Octa Patterns (LOtP), Local Hexadeca Patterns (LHdP) and Direction Encoded Local Binary Pattern (DELBP). LOtP and LHdP encode the relationship between center pixel and its neighbors based on the pixels’ direction obtained by considering the horizontal, vertical and diagonal pixels for derivative calculations. In DELBP, direction of a referenced pixel is determined by considering every neighboring pixel for derivative calculations which results in 256 directions. For this resultant direction encoded image, we have obtained LBP which is considered as feature vector. The proposed method’s performance is compared to that of Local Tetra Patterns (LTrP) using benchmark image databases viz., Corel 1000 (DB1) and Brodatz textures (DB2). Performance analysis shows that LOtP improves the average precision from 59.31% to 64.36% on DB1, and from 83.24% to 85.95% on DB2, LHdP improves it to 65.82% on DB1 and to 87.49% on DB2 and DELBP improves it to 60.35% on DB1 and to 86.12% on DB2 as compared to that of LTrP. Also, DELBP reduces the feature vector length by 66.62% as compared to that of LTrP. To reduce the retrieval time, the proposed algorithms are implemented on a Hadoop cluster consisting of 116 nodes and tested using Corel 10K (DB3), Mirflickr 100,000 (DB4) and ImageNet 511,380 (DB5) databases.
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Dueland, S., R. Blomhoff, and J. I. Pedersen. "Uptake and degradation of vitamin D binding protein and vitamin D binding protein–actin complex in vivo in the rat." Biochemical Journal 267, no. 3 (May 1, 1990): 721–25. http://dx.doi.org/10.1042/bj2670721.
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We have labelled the rat vitamin D binding protein (DBP), DBP-actin and rat albumin with 125I-tyramine-cellobiose (125I-TC). In contrast with traditional 125I-labelling techniques where degraded radioactive metabolites are released into plasma, the 125I-TC moiety is trapped intracellularly in the tissues, where the degradation of the labelled proteins takes place. By using this labelling method, the catabolism of proteins can be studied in vivo. In this study we have used this labelling technique to compare the tissue uptake and degradation of DBP, DBP-actin and albumin in the rat. DBP-actin was cleared from plasma at a considerably faster rate than DBP. After intravenous injection of labelled DBP-actin complex, 48% of the radioactive dose was recovered in the liver after 30 min, compared with 14% when labelled DBP was administered. Only small amounts of DBP-actin complex were recovered in the kidneys. In contrast with the results obtained with DBP-actin complex, liver and kidneys contributed about equally in the uptake and degradation of DBP determined 24 h after the injection. When labelled DBP was compared with labelled albumin, the amount of radioactivity taken up by the liver and kidneys by 24 h after the injection was 2 and 5 times higher respectively. In conclusion, liver and kidneys are the major organs for catabolism of DBP in the rat. Furthermore, binding of actin to DBP enhances the clearance of DBP from circulation as well as its uptake by the liver.
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Berg, Anders H., Mahtab Tavasoli, Agnes S. Lo, Sherri-Ann M. Burnett-Bowie, Ishir Bhan, S. Ananth Karumanchi, Sahir Kalim, Dongsheng Zhang, Sophia Zhao, and Ravi I. Thadhani. "Development and analytical validation of a novel bioavailable 25-hydroxyvitamin D assay." PLOS ONE 16, no. 7 (July 9, 2021): e0254158. http://dx.doi.org/10.1371/journal.pone.0254158.
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Background Bioavailable 25-hydroxyvitamin D (25OHD) may be a better indicator of vitamin D sufficiency than total 25OHD. This report describes a novel assay for measuring serum bioavailable 25OHD. Methods We developed an assay for 25OHD % bioavailability based on competitive binding of 25OHD tracer between vitamin D-binding protein (DBP)-coated affinity chromatography beads and serum DBP. Bioavailable 25OHD, total 25OHD, albumin, and DBP protein concentrations were measured in 89 samples from hospitalized patients and 42 healthy controls to determine how the DBP binding assay responds to differences in concentrations of DBP and compares to calculated bioavailable 25OHD values. Results DBP binding assay showed a linear relationship between DBP-bound 25OHD tracer recovered from bead supernatant and DBP calibrator concentrations (y = 0.0017x +0.731, R2 = 0.9961, p<0.001). Inversion of this relationship allowed interpolation of DBP binding equivalents based upon 25OHD tracer recovered. The relationship between DBP binding equivalents and % bioavailability fits a non-linear curve, allowing calculation of % bioavailable 25OHD from DBP binding equivalents (y = 10.625x-0.817, R2 = 0.9961, p<0.001). In hospitalized patient samples, there were linear relationships between DBP protein concentrations and DBP binding equivalents (y = 0.7905x + 59.82, R2 = 0.8597, p<0.001), between measured vs. calculated % bioavailability (y = 0.9528 + 0.0357, R2 = 0.7200, p<0.001), and between absolute concentrations of measured vs. calculated bioavailable 25OHD (y = 1.2403 + 0.1221, R2 = 0.8913, p<0.001). Conclusions The DBP-binding assay for bioavailable 25OHD shows expected changes in 25OHD % bioavailability in response to changes in DBP concentrations and concordance with calculated bioavailable 25OHD concentrations.
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Decken, Andreas, Melanie A. Neil, and Frank Bottomley. "Synthesis and characterization of manganese complexes of the dibenzophospholyl ligand." Canadian Journal of Chemistry 79, no. 9 (September 1, 2001): 1321–29. http://dx.doi.org/10.1139/v01-124.
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Manganese carbonyl complexes bearing dibenzophospholyl (DBP) and 1-phenyldibenzophosphole (Ph-DBP) ligands have been prepared. Reaction of Li-DBP with Mn(CO)5Br gave (µ2-DBP)(µ2-Br)Mn2(CO)8, while reaction of bis(1,1'-dibenzophospholyl) and Mn2(CO)10 yielded (µ2-DBP)2Mn2(CO)8. The phosphine adducts (Ph-DBP)Mn2(CO)9 and (Ph-DBP)2Mn2(CO)8 were obtained by reaction of Ph-DBP and Mn2(CO)10. The ligands are σ-bonded through the phosphorus atom in all complexes. The compounds were characterized by 1H, 13C, and 31P NMR and IR spectroscopy, mass spectrometry, and X-ray diffraction.Key words: dibenzophospholyl, dibenzophosphole, manganese, heterocycle.
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Richards, Jack S., and Paul A. Ramsland. "Human antibodies against DBP." Nature Microbiology 4, no. 9 (August 22, 2019): 1428–29. http://dx.doi.org/10.1038/s41564-019-0549-8.
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Diehl, Alicia C., Gerald E. Speitel, James M. Symons, Stuart W. Krasner, Cordelia J. Hwang, and Sylvia E. Barrett. "DBP formation during chloramination." Journal - American Water Works Association 92, no. 6 (June 2000): 76–90. http://dx.doi.org/10.1002/j.1551-8833.2000.tb08961.x.
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Waniale, Allan, Rony Swennen, Settumba B. Mukasa, Arthur K. Tugume, Jerome Kubiriba, Wilberforce K. Tushemereirwe, Michael Batte, Allan Brown, and Robooni Tumuhimbise. "Seed Set Patterns in East African Highland Cooking Bananas Are Dependent on Weather before, during and after Pollination." Horticulturae 7, no. 7 (June 29, 2021): 165. http://dx.doi.org/10.3390/horticulturae7070165.
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Seed set in banana is influenced by weather, yet the key weather attributes and the critical period of influence are unknown. We therefore investigated the influence of weather during floral development for a better perspective of seed set increase. Three East African highland cooking bananas (EAHBs) were pollinated with pollen fertile wild banana ‘Calcutta 4′. At full maturity, bunches were harvested, ripened, and seeds extracted from fruit pulp. Pearson’s correlation analysis was then conducted between seed set per 100 fruits per bunch and weather attributes at 15-day intervals from 105 days before pollination (DBP) to 120 days after pollination (DAP). Seed set was positively correlated with average temperature (P < 0.05–P < 0.001, r = 0.196–0.487) and negatively correlated with relative humidity (RH) (P < 0.05–P < 0.001, r = −0.158–−0.438) between 75 DBP and the time of pollination. After pollination, average temperature was negatively correlated with seed set in ‘Mshale’ and ‘Nshonowa’ from 45 to 120 DAP (P < 0.05–P < 0.001, r = −0.213–−0.340). Correlation coefficients were highest at 15 DBP for ‘Mshale’ and ‘Nshonowa’, whereas for ‘Enzirabahima’, the highest were at the time of pollination. Maximum temperature as revealed by principal component analysis at the time of pollination should be the main focus for seed set increase.
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Gan, Xiaojie, Tanju Karanfil, S. Sule Kaplan Bekaroglu, and Junhong Shan. "The control of N-DBP and C-DBP precursors with MIEX®." Water Research 47, no. 3 (March 2013): 1344–52. http://dx.doi.org/10.1016/j.watres.2012.11.049.
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Smolders, Joost, Evelyn Peelen, Mariëlle Thewissen, Paul Menheere, Jan Damoiseaux, and Raymond Hupperts. "Circulating vitamin D binding protein levels are not associated with relapses or with vitamin D status in multiple sclerosis." Multiple Sclerosis Journal 20, no. 4 (August 19, 2013): 433–37. http://dx.doi.org/10.1177/1352458513500552.
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Background: A low vitamin D status has been associated with multiple sclerosis (MS). Most circulating vitamin D metabolites are bound to vitamin D binding protein (DBP). Objectives: The purpose of this study was to explore whether there is an association between MS and DBP. Methods: We compared DBP concentrations in blood samples of controls ( n = 30) and subjects with relapsing–remitting MS (RRMS) during remission ( n = 29) and relapse ( n = 15). Furthermore, we explored correlations of DBP with 25- hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D levels (1,25(OH)2D), and the effect of high-dose vitamin D3 supplementation on DBP levels in RRMS patients ( n = 15). Results: DBP-concentration did not differ between the sub-groups measured, and there was no correlation between DBP and vitamin D metabolite concentration within the physiological range. Upon supplementation of high doses vitamin D3, DBP concentration remained unaltered. After supplementation, serum 1,25(OH)2D( R = 0.517, p = 0.049), but not 25(OH)D, correlated positively with DBP. Conclusions: We found no association between DBP, MS, and vitamin D status within the physiological range. After high - dose vitamin D supplementation, DBP concentrations may be relevant for vitamin D metabolism.
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Krausz, Ronald F., George Kapusta, and Joseph L. Matthews. "Soybean (Glycine max) Tolerance to 2,4-D Ester Applied Preplant." Weed Technology 7, no. 4 (December 1993): 906–10. http://dx.doi.org/10.1017/s0890037x00037970.
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Field studies were conducted in 1991 and 1992 to determine potential soybean injury due to 2,4-D ester at 560, 1120, and 1680 g ai/ha applied 0, 7, and 14 d before planting (DBP). Delayed emergence and increased injury of soybean were observed as 2,4-D rate increased and interval between application and planting decreased. Delay in emergence ranged from 0 to 67% and 0 to 50% in 1991 and 1992, respectively. Injury at 15 days after planting (DAP) combined over years ranged from 0 to 61%. Minimal (0 to 8%) delay in emergence and minimal (0 to 5%) injury at 15, 30, 45, and 60 DAP occurred when 2,4-D at 560 or 1120 g/ha was applied 7 or 14 DBP. No significant yield reduction occurred due to 2,4-D rate, application timing, or their interaction.
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Liao, Chien-Sen, Yoshikazu Nishikawa, and Yu-Ting Shih. "Characterization of Di-n-Butyl Phthalate Phytoremediation by Garden Lettuce (Lactuca sativa L. var. longifolia) through Kinetics and Proteome Analysis." Sustainability 11, no. 6 (March 18, 2019): 1625. http://dx.doi.org/10.3390/su11061625.
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Di-n-dutyl phthalate (DBP), an endocrine disruptor, is one of the most widely used phthalate esters (PAEs) in the world. It can be accumulated in seafood or agricultural products and represents a substantial risk to human health via the food chain. Thus, finding a plant which can remediate DBP but have no effects on growth is the main topic of the development of DBP phytoremediation. This study used garden lettuce (Lactuca sativa L. var. longifolia), which has a significant DBP absorption capability, as a test plant to measure phytoremediation kinetics and proteome changes after being exposed to DBP. The results show that DBP accumulated in different parts of the garden lettuce but the physiological status and morphology showed no significant changes following DBP phytoremediation. The optimal condition for the DBP phytoremediation of garden lettuce is one critical micelle concentration (CMC) of non-ionic surfactant Tween 80 and the half-life (t1/2, days), which calculated by first-order kinetics, was 2.686 days for 5 mg L−1 of DBP. This result indicated that the addition of 1 CMC of Tween 80 could enhance the efficiency of DBP phytoremediation. In addition, the results of biotoxicity showed that the median effective concentration (EC50) of DBP for Chlorella vulgaris is 4.9 mg L−1. In this case, the overall toxicity markedly decreased following phytoremediation. In the end, the result of proteome analysis showed six protein spots, revealing significant alterations. According to the information of these proteomes, DBP potentially causes osmotic and oxidative stress in garden lettuce. In addition, since DBP had no significant effects on the morphology and physiological status of garden lettuce, garden lettuce can be recommended for use in the plant anti-DBP toxicity test, and also as the candidate plant for DBP phytoremediation. We hope these findings could provide valuable information for DBP-contaminated water treatment in ecological engineering applications or constructed wetlands.
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Decken, Andreas, Melanie A. Neil, C. Adam Dyker, and Frank Bottomley. "Iron complexes of the dibenzophospholyl ligand: a synthetic and crystallographic study." Canadian Journal of Chemistry 80, no. 1 (January 1, 2002): 55–61. http://dx.doi.org/10.1139/v01-193.
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Iron complexes bearing the dibenzophospholyl (DBP) ligand have been prepared. Reaction of DBP-Li with CpFe(CO)2Br gave [(µ2-DBP)Fe2Cp2(CO)4]Br and reaction of DBP-Li with CpFe(CO)2I gave [(µ2-DBP)Fe2Cp2(CO)4]I. Reaction of bis(1,1'-dibenzophospholyl) and [CpFe(CO)2]2 yielded a mixture of cis- and trans-(µ2-DBP)2Fe2Cp2(CO)2. The mixture was also obtained on heating of [(µ2-DBP)Fe2Cp2(CO)4]X (X = Br, I). The ligands are sigma-bonded through the phosphorus atom in all complexes. The compounds were characterized by 1H, 13C, and 31P NMR and IR spectroscopies, mass spectrometry, micro analysis, and X-ray diffraction.Key words: dibenzophospholyl, iron, heterocycle.
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Shen, Chenchen, Jie Wei, Tianyi Wang, and Yuan Wang. "Acute toxicity and responses of antioxidant systems to dibutyl phthalate in neonate and adult Daphnia magna." PeerJ 7 (March 14, 2019): e6584. http://dx.doi.org/10.7717/peerj.6584.
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Dibutyl phthalate (DBP) poses a severe threat to aquatic ecosystems, introducing hazards to both aquatic species and human health. The ecotoxic effects of DBP on aquatic organisms have not been fully investigated. This study investigates acute toxicity, oxidative damage, and antioxidant enzyme parameters in neonate and adult Daphnia magna exposed to DBP. The obtained results show comparable DBP toxic responses in neonates and adults. The median lethal concentrations (LC50) of DBP in neonates exposed for 24 and 48 h were 3.48 and 2.83 mg/L, respectively. The LC50 of adults for the same DBP exposure durations were 4.92 and 4.31 mg/L, respectively. Increased hydrogen peroxide and malondialdehyde were found in neonates and adults at both 24 and 48 h, while the total antioxidant capacity decreased. Superoxide dismutase activity increased significantly in neonates and adults exposed to 0.5 mg/L DBP, and subsequently diminished at higher DBP concentrations and prolonged exposure. Catalase and glutathione S-transferases activities both decreased markedly in neonates and adults. The changes observed were found to be time and concentration dependent. Overall, these data indicated that the acute toxic effects of DBP exposure on neonates were more pronounced than in adults, and oxidative injury may be the main mechanism of DBP toxicity. These results provide a functional link for lipid peroxidation, antioxidant capacity, and antioxidant enzyme levels in the Daphnia magna response to DBP exposure.
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Zhang, Xin, Huanxin Meng, Li Xu, Li Zhang, Dong Shi, Xianghui Feng, Ruifang Lu, and Zhibin Chen. "Vitamin D-Binding Protein Levels in Plasma and Gingival Crevicular Fluid of Patients with Generalized Aggressive Periodontitis." International Journal of Endocrinology 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/783575.
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Vitamin D-binding protein (DBP) is the main transport protein of vitamin D and plays an important role in the immune system and host defenses. The purpose of this study was to measure DBP levels in plasma and gingival crevicular fluid (GCF) of patients with generalized aggressive periodontitis (GAgP), in comparison to healthy controls, with the goal of elucidating the relationship between DBP and GAgP. Fifty-nine GAgP patients and 58 healthy controls were recruited for the study; clinical parameters of probing depths (PD), bleeding index, and attachment loss (AL) were recorded. DBP levels were measured by enzyme-linked immunosorbent assay. From the results, GAgP patients had higher plasma DBP concentrations (P<0.001) but lower GCF DBP concentrations (P<0.001) than healthy controls. In GAgP group, after controlling the potential confounders of age, gender, smoking status, and BMI index, GCF DBP concentrations correlated negatively with PD (P<0.001) and AL (P=0.009). Within the limits of the study, we concluded that decreased GCF DBP level and increased plasma DBP level are associated with periodontitis.
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Kew, RR, MA Sibug, JP Liuzzo, and RO Webster. "Localization and quantitation of the vitamin D binding protein (Gc- globulin) in human neutrophils." Blood 82, no. 1 (July 1, 1993): 274–83. http://dx.doi.org/10.1182/blood.v82.1.274.bloodjournal821274.
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Plasma-derived vitamin D binding protein (DBP) is an important physiologic regulator of the neutrophil chemotactic response to activated complement. A cell-associated form of DBP has been observed in numerous cell types. We now report that mature, circulating human neutrophils also contain cell-associated DBP. Immunofluorescence studies of normal untreated neutrophils showed the presence of DBP on the cell surface. Western blotting of detergent-soluble neutrophil lysates with a polyclonal anti-DBP showed two major immunoreactive bands, one with an apparent molecular weight of 56 Kd (identical to purified plasma-derived DBP) and a second less prominent band at 12 to 14 Kd. Quantitation of the immunoreactive bands by video densitometry indicated that normal human neutrophils contain 1.5 +/- 0.8 ng DBP/10(6) cells (n = 9). Immunoprecipitation of detergent-soluble lysates with the polyclonal anti-DBP showed only the 56-Kd form by Western blotting. In contrast, a monoclonal anti-DBP immunoprecipitated the 12 to 14 Kd form of DBP from lysates of surface-radioiodinated cells. Western blots of subcellular fractions showed that immunoreactive bands were found in the specific (secondary) granule and plasma-membrane fractions. In addition, pretreatment of neutrophils with 10 nmol/L phorbol myristate acetate (PMA) resulted in approximately a 50% reduction in the amount of DBP in both the specific granule and plasma-membrane fractions. Finally, analysis of the cell- free supernates showed that DBP was spontaneously released into the extracellular milieu: moreover, this release was enhanced if the cells were first stimulated with C5a, formyl-norleucyl-leucyl-phenylalanine (fNLP) or PMA.
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Shalamova, E. Yu, O. N. Ragozin, and M. V. Bochkarev. "Disadaptive reactions of the cardiovascular system in relation to sleep and coping behavior in students of northern medical institute." "Arterial’naya Gipertenziya" ("Arterial Hypertension") 25, no. 2 (July 29, 2019): 176–90. http://dx.doi.org/10.18705/1607-419x-2019-25-2-176-190.
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The aim of the study is to assess the relation between hemodynamic parameters and coping behavior and sleep in order to maintain health of students of the northern university. Design and methods. We examined 96 students of the northern medical university (61 females). During academic days, we performed ambulatory monitoring of blood pressure (ABPM) 24 h + 10–120 minutes. We analyzed following parameters: mezors of heart rate (HR), systolic (SBP), diastolic (DBP), and pulse blood pressure (BP), mean BP, Kerdo autonomic index (KI), functional change index (FCI); hypertension time indices of SBP (TI SBP) and DBD (TI DBP) (%), variability of SBP (Var. SBD) and DBD (Var. DBP); night dipping of SBP and DBP (%). We assessed coping behavior. The sleep was assessed using the subjective characteristics of sleep questionnaire and the Epworth sleepiness scale. Statistical analysis was performed using Statistica 10.0 and Excel 2013 software. Results. We found optimal/normal values of mean BP and intersexual differences among students. Female students in all periods showed higher rates of HR and sympathetic influences; males had higher SBD, higher TI SBP during day and night, higher SBP variability at night, and tended to develop isolated systolic hypertension. Parameters and dynamics of the vascular component of BP are in normal ranges. We did not find significant intersexual differences in mechanisms of the vascular regulation. Cardiovascular system regulation in males depended on the sleep and coping, and it was more autonomous from behavior in girls. Conclusions. One of the most effective and affordable ways to prevent cardiovascular diseases during the university education is the consistent training of students in adaptive behavior in a situation of psycho-emotional stress and recommendations on sleep hygiene. Greater efficiency of the learning adaptive coping behavior can be expected in males, and male gender is one of the non-modifiable risk factors for cardiovascular pathology.
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Liang, F., J. Xi, X. Chen, J. Huang, D. Jin, and X. Zhu. "Curcumin decreases dibutyl phthalate-induced renal dysfunction in Kunming mice via inhibiting oxidative stress and apoptosis." Human & Experimental Toxicology 40, no. 9 (March 17, 2021): 1528–36. http://dx.doi.org/10.1177/09603271211001124.
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Curcumin (Cur) has been used extensively in dietary supplement with antioxidant and anti-apoptotic properties. Although dibutyl phthalate (DBP) has adverse effects on the kidney, any association between DBP exposure and the role of Cur is unclear. We tested the hypothesis that exposure to DBP has adverse consequences on renal dysfunction in mice and the potential protective role of Cur in decreasing DBP-induced renal dysfunction via inhibiting oxidative stress and apoptosis. Kidney function, oxidative stress biomarkers, and apoptosis factors as well as Bcl-2 and Bax were investigated. The results showed a marked increase of renal dysfunction, oxidative stress and apoptosis level after DBP exposure compared to the control. While administration of Cur to DBP-treated mice may reduce these adverse biochemical changes compared with DBP-alone group. Overall, these results suggest that oxidative stress and apoptosis are involved in DBP-induced renal disorder, whereas Cur plays a protective role in inhibiting these two pathways.
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Li, Zhaoying, Weijing Wang, Xiaocao Tian, Haiping Duan, Chunsheng Xu, and Dongfeng Zhang. "Bivariate genome-wide association study (GWAS) of body mass index and blood pressure phenotypes in northern Chinese twins." PLOS ONE 16, no. 2 (February 4, 2021): e0246436. http://dx.doi.org/10.1371/journal.pone.0246436.
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Recently, new loci related to body mass index (BMI) or blood pressure (BP) have been identified respectively in genome-wide association studies (GWAS). However, limited studies focused on jointly associated genetic variance between systolic pressure (SBP), diastolic pressure (DBP) and BMI. Therefore, a bivariate twin study was performed to explore the genetic variants associated with BMI-SBP, BMI-DBP and SBP-DBP. A total of 380 twin pairs (137 dizygotic pairs and 243 monozygotic pairs) recruited from Qingdao Twin Registry system were used to access the genetic correlations (0.2108 for BMI-SBP, 0.2345 for BMI-DBP, and 0.6942 for SBP-DBP, respectively) by bivariate Cholesky decomposition model. Bivariate GWAS in 137 dizygotic pairs nominated 27 single identified 27 quantitative trait nucleotides (QTNs) for BMI and SBP, 27 QTNs for BMI and DBP, and 25 QTNs for SBP and DBP with the suggestive P-value threshold of 1×10−5. After imputation, we found eight SNPs, one for both BMI-SBP and SBP-DBP, and eight for SBP-DBP, exceed significant statistic level. Expression quantitative trait loci analysis identified rs4794029 as new significant eQTL in tissues related to BMI and SBP. Also, we found 6 new significant eQTLs (rs4400367, rs10113750, rs11776003, rs3739327, rs55978930, and rs4794029) in tissues were related to SBP and DBP. Gene-based analysis identified nominally associated genes (P < 0.05) with BMI-SBP, BMI-DBP, and SBP-DBP, respectively, such as PHOSPHO1, GNGT2, KEAP1, and S1PR5. In the pathway analysis, we found some pathways associated with BMI-SBP, BMI-DBP and SBP-DBP, such as prion diseases, IL5 pathway, cyclin E associated events during G1/S transition, TGF beta signaling pathway, G βγ signaling through PI3Kγ, prolactin receptor signaling etc. These findings may enrich the results of genetic variants related to BMI and BP traits, and provide some evidences to future study the pathogenesis of hypertension and obesity in the northern Chinese population.
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Yu, Jian, Yu Fu, Ming Jie Jiang, and Wen Hui Ren. "Biodegradation of DBP by Biofilm Reactor." Applied Mechanics and Materials 178-181 (May 2012): 390–99. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.390.
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The removal efficiency of dibutyl phthalate (DBP) and its environmental hormone treated by biofilm reactor has been investigated. Besides, the the kinetic model of the degradation of DBP and its degradation products in the reactor have been discussed. The results indicate that the biofilm reactor had a positive effect on the removal of DBP and was able to significantly reduce the environmental hormone in DBP influent. The activity of β-galactosidase dropped from 13.55 millers to 3.3 millers and the removal efficiency of DBP reached 98.5% at water temperature 20°C and HRT (Hydraulic Retention Time) of 4 hours. The metabolic intermediate of DBP in the reactor mainly consisted of dibutyl phthalate and phthalic acid. The kinetic models of the degradation of DBP can be expressed by Lawrence-McCarty equation.
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Dueland, S., M. S. Nenseter, and C. A. Drevon. "Uptake and degradation of filamentous actin and vitamin D-binding protein in the rat." Biochemical Journal 274, no. 1 (February 15, 1991): 237–41. http://dx.doi.org/10.1042/bj2740237.
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Tissue uptake and degradation of 125I-tyramine-cellobiose-labelled filamentous actin, vitamin D-binding protein (DBP) and actin-DBP complex were studied in the rat. Actin and actin-DBP complex were cleared from plasma at a faster rate than was DBP. About 40% of injected actin was recovered in the liver between 10 and 30 min after administration. Of the total radioactivity recovered in the liver, about 35% and 40% was detected in parenchymal and endothelial cells respectively when labelled actin or DBP-actin complex was injected intravenously. When labelled DBP alone was injected, approx. 55% of the radioactivity recovered in liver was in the Kupffer cells. These results suggest that actin is targeting the DBP-actin complex to the endothelial and parenchymal liver cells. Filamentous actin was also taken up in large amounts and at a rapid rate in parenchymal as well as non-parenchymal liver cells in vitro. Our data indicate that the rat has a mechanism to clear actin and the DBP-actin complex from plasma and that both parenchymal and non-parenchymal liver cells are involved in this process.
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Duchow, Elizabeth G., Nancy E. Cooke, Jeremy Seeman, Lori A. Plum, and Hector F. DeLuca. "Vitamin D binding protein is required to utilize skin-generated vitamin D." Proceedings of the National Academy of Sciences 116, no. 49 (November 20, 2019): 24527–32. http://dx.doi.org/10.1073/pnas.1915442116.
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Vitamin D is produced in the skin following exposure to sunlight. Ultraviolet (UV) B (UVB, 280–310 nm) results in isomerization of 7-dehydrocholesterol to previtamin D that spontaneously isomerizes to vitamin D. This pool of skin-derived vitamin D is the major source of vitamin D for animals. However, the mechanisms by which it becomes available remain undefined. It has been assumed that cutaneous vitamin D is transported into the circulation by vitamin D binding protein (DBP), but experimental evidence is lacking. To determine whether cutaneous vitamin D is transported by DBP, we utilized DBP−/− mice that were made vitamin D-deficient. These animals lack measurable 25(OH)D in blood and are hypocalcemic. As controls, DBP+/+ animals were vitamin D depleted and made equally hypocalcemic. UV irradiation of DBP+/+ animals restored serum calcium and serum 25(OH)D while the same treatment of DBP−/− animals failed to show either a serum calcium or 25(OH)D response despite having normal vitamin D production in skin. Intravenous injection of small amounts of recombinant DBP to the vitamin D-deficient DBP−/− mice restored the response to UV light. These results demonstrate a requirement for DBP to utilize cutaneously produced vitamin D.
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Chang, Tara I., Guo Wei, Robert Boucher, Holly Kramer, Glenn M. Chertow, Alfred K. Cheung, Tom Greene, Paul K. Whelton, and Srinivasan Beddhu. "Baseline Diastolic Blood Pressure and Cardiovascular Outcomes in SPRINT Participants with Chronic Kidney Disease." Kidney360 1, no. 5 (March 31, 2020): 368–75. http://dx.doi.org/10.34067/kid.0000982019.
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BackgroundWe sought to determine whether intensive systolic BP (SBP) lowering was harmful in Systolic Blood Pressure Intervention Trial (SPRINT) participants with CKD (eGFR<60 ml/min per 1.73 m2) and lower baseline diastolic BP (DBP).MethodsWe related baseline DBP with the SPRINT primary composite end point (myocardial infarction, acute coronary syndrome, stroke, acute decompensated heart failure, or cardiovascular death) and all-cause death. We examined the effect of intensive SBP lowering on these outcomes across the range of baseline DBPs using Cox regression with treatment by baseline DBP interaction terms.ResultsAmong 2646 SPRINT participants with CKD, lower baseline DBP was associated with a higher adjusted hazard of the primary composite end point and all-cause death. For example, participants with baseline DBP of 61 mm Hg (mean baseline DBP in the lowest tertile) experienced a 37% (95% CI, 7% to 75%) higher hazard of the primary outcome relative to participants with baseline DBP of 75 mm Hg (mean baseline DBP for overall). The benefit of intensive SBP lowering was consistent across a range of baseline DBPs on rates of the primary composite end point (linear interaction P value =0.56) and all-cause death (linear interaction P value =0.20).ConclusionsAmong SPRINT participants with baseline CKD, lower DBP was associated with higher rates of the primary composite end point and all-cause death. However, DBP did not seem to modify the benefit of intensive SBP lowering on the primary composite end point or all-cause death. Our results suggest that lower DBP should not necessarily impede more intensive SBP lowering in patients with mild to moderate CKD.
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Povaliaeva, Alexandra A., Ekaterina A. Pigarova, Anastasia A. Romanova, Larisa K. Dzeranova, Artem Y. Zhukov, and Liudmila Y. Rozhinskaya. "Vitamin D-binding protein: multifunctional component of blood serum." Annals of the Russian academy of medical sciences 76, no. 1 (April 12, 2021): 103–10. http://dx.doi.org/10.15690/vramn1396.
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Vitamin D-binding protein (DBP) was discovered more than half a century ago as a polymorphic serum protein and is currently characterized by a variety of physiological properties. First of all, DBP carries the bulk of vitamin D metabolites circulating in the bloodstream, while albumin is the second most important transport protein, especially in patients with a low concentration of DBP in serum. Since it was discovered that only 12% of the total circulating DBP have occupied steroid binding sites, a vigorous study of other potential biological roles of DBP was initiated: actin utilization, regulation of inflammation and innate immunity mechanisms, fatty acid binding, effects on bone metabolism and participation in the tumor pathogenesis. This review focuses on the main known biological functions of DBP.
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Oda, S. S., and R. S. Waheeb. "Ginger attenuated di (n-butyl) phthalate-induced reproductive toxicity in pubertal male rabbits." World Rabbit Science 25, no. 4 (December 28, 2017): 387. http://dx.doi.org/10.4995/wrs.2017.7466.
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This study was conducted to investigate the toxic effects of di (n-butyl) phthalate (DBP) on reproductive functions in male rabbits and the probable protective role of ginger. Twenty rabbits were divided equally into 4 groups: control group; DBP group (520 mg/kg body weight [BW] DBP orally), DBP+ginger group (520 mg/kg BW DBP and 400 mg/kg BW ginger) and ginger group (400 mg/kg BW ginger orally). Treatments were given three-times/week. After 7 wk of the experiment, DBP induced significant reduction in testis and prostate weights, serum and intratesticular testosterone concentrations, sperm counts both mass and progressive sperm motility and live sperms percentage as well as significant elevation of testicular malondialdehyde compared to control group. No significant changes were detected in epididymal weights, serum FSH and serum LH concentrations and testicular total superoxide dismutase and glutathione peroxidase activities in all treated groups. DBP induced considerable histopathological alterations in testis and to minimal extent in epididymis and prostates. Ginger treatment attenuated the significant changes to a certain extent induced by DBP intoxication in male rabbits probably due to its potential to scavenge free radicals.
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Li, Linxi, Xiaomin Chen, Guoxin Hu, Sicong Wang, Renai Xu, Qiqi Zhu, Xiaoheng Li, Mingcang Wang, Qing-Quan Lian, and Ren-Shan Ge. "Comparison of the Effects of Dibutyl and Monobutyl Phthalates on the Steroidogenesis of Rat Immature Leydig Cells." BioMed Research International 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/1376526.
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Dibutyl phthalate (DBP) is a widely used synthetic phthalic diester and monobutyl phthalate (MBP) is its main metabolite. DBP can be released into the environment and potentially disrupting mammalian male reproductive endocrine system. However, the potencies of DBP and MBP to inhibit Leydig cell steroidogenesis and their possible mechanisms are not clear. Immature Leydig cells isolated from rats were cultured with 0.05–50 μM DBP or MBP for 3 h in combination with testosterone synthesis regulator or intermediate. The concentrations of 5α-androstanediol and testosterone in the media were measured, and the mRNA levels of the androgen biosynthetic genes were detected by qPCR. The direct actions of DBP or MBP on CYP11A1, CYP17A1, SRD5A1, and AKR1C14 activities were measured. MBP inhibited androgen production by the immature Leydig cell at as low as 50 nM, while 50 μM was required for DBP to suppress its androgen production. MBP mainly downregulatedCyp11a1andHsd3b1expression levels at 50 nM. However, 50 μM DBP downregulatedStar,Hsd3b1, andHsd17b3expression levels and directly inhibited CYP11A1 and CYP17A1 activities. In conclusion, DBP is metabolized to more potent inhibitor MBP that downregulated the expression levels of some androgen biosynthetic enzymes.
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Steckel, Lawrence E., C. Chism Craig, and Robert M. Hayes. "Glyphosate-resistant Horseweed (Conyza Canadensis) Control with Glufosinate Prior to Planting No-till Cotton (Gossypium Hirsutum)." Weed Technology 20, no. 4 (December 2006): 1047–51. http://dx.doi.org/10.1614/wt-05-183.1.
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Control of glyphosate-resistant (GR) horseweed in no-till cotton has become a serious challenge for midsouth producers. Control of GR horseweed prior to no-till cotton planting (burndown) was examined with glufosinate applied at a standard rate (0.47 kg ai/ha) 30, 21, and 14 d before planting (DBP) and at 0.35 and 0.58 kg ai/ha 14 DBP. Glufosinate at 0.47 kg ai/ha was also tank-mixed with 2,4-D, dicamba, or flumioxazin 30 DBP, and with diuron, pendimethalin, prometryn, or glyphosate at 14 DBP. Glufosinate applied at the standard rate 21 or 30 DBP did not control GR horseweed (<55%), but did provide better control (85%) when applied 14 DBP. The high rate of glufosinate (0.58 kg ai/ha) applied 14 DBP controlled GR horseweed. Tank mixtures of glufosinate with dicamba or 2,4-D at 30 DBP controlled GR horseweed. Tank mixtures of glufosinate with either prometryn or diuron provided initial burndown and residual weed control. Tank mixtures of glufosinate + pendimethalin or flumioxazin did not increase control of existing horseweed, but did provide residual control 56 days after application.
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van Breukelen, Bas, Arjan B. Brenkman, P. Elly Holthuizen, and Peter C. van der Vliet. "Adenovirus Type 5 DNA Binding Protein Stimulates Binding of DNA Polymerase to the Replication Origin." Journal of Virology 77, no. 2 (January 15, 2003): 915–22. http://dx.doi.org/10.1128/jvi.77.2.915-922.2003.
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ABSTRACT The adenovirus (Ad) DNA-binding protein (DBP) is essential for the elongation phase of Ad DNA replication by unwinding the template in an ATP-independent fashion, employing its capacity to form multimers. DBP also enhances the rate of initiation, with the highest levels obtained at low concentrations of Ad DNA polymerase (Pol). Here, we show that stimulation of initiation depends on the template conformation. Maximal stimulation, up to 15-fold, is observed on double-stranded or viral TP-containing origins. The stimulation is reduced on partially single-stranded origins and DBP does not enhance initiation any more once the origin is completely unwound. This suggests a role for DBP in origin unwinding that is comparable to its unwinding capacity during elongation. However, mutant DBP proteins defective in unwinding and elongation can still enhance initiation on ds templates. DBP also stimulates the binding of nuclear factor I (NFI) to the origin and lowers the Km for coupling of the first nucleotide to the precursor terminal protein by Pol. Mobility shift experiments reveal that DBP stimulates the binding of Pol on double-stranded origin and nonorigin DNA but not on single-stranded DNA. This effect is specific for DBP and is also seen with other DNA Pols. Our results suggest that, rather than by origin unwinding, DBP enhances initiation by modulating the origin conformation such that DNA Pol can bind more efficiently.
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Mikhailov, Victor S., Alla L. Mikhailova, Masashi Iwanaga, Sumiko Gomi, and Susumu Maeda. "Bombyx mori Nucleopolyhedrovirus Encodes a DNA-Binding Protein Capable of Destabilizing Duplex DNA." Journal of Virology 72, no. 4 (April 1, 1998): 3107–16. http://dx.doi.org/10.1128/jvi.72.4.3107-3116.1998.
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ABSTRACT A DNA-binding protein (designated DBP) with an apparent molecular mass of 38 kDa was purified to homogeneity from BmN cells (derived fromBombyx mori) infected with the B. morinucleopolyhedrovirus (BmNPV). Six peptides obtained after digestion of the isolated protein with Achromobacter protease I were partially or completely sequenced. The determined amino acid sequences indicated that DBP was encoded by an open reading frame (ORF16) located at nucleotides (nt) 16189 to 17139 in the BmNPV genome (GenBank accession no. L33180 ). This ORF (designated dbp) is a homolog of Autographa californica multicapsid NPV ORF25, whose product has not been identified. BmNPV DBP is predicted to contain 317 amino acids (calculated molecular mass of 36.7 kDa) and to have an isoelectric point of 7.8. DBP showed a tendency to multimerization in the course of purification and was found to bind preferentially to single-stranded DNA. When bound to oligonucleotides, DBP protected them from hydrolysis by phage T4 DNA polymerase-associated 3′→5′ exonuclease. The sizes of the protected fragments indicated that a binding site size for DBP is about 30 nt per protein monomer. DBP, but not BmNPV LEF-3, was capable of unwinding partial DNA duplexes in an in vitro system. This helix-destabilizing ability is consistent with the prediction that DBP functions as a single-stranded DNA binding protein in virus replication.
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Shinkut, M., T. Aluwong, P. I. Rekwot, J. S. Bugau, F. U. Samuel, and W. O. Echekwu. "Melatonin and Allium Sativum (Garlic) Protect Dibutyl Phthalate Influence on Spermiogram of Rabbit Bucks." Nigerian Veterinary Journal 41, no. 1 (April 16, 2021): 47–61. http://dx.doi.org/10.4314/nvj.v41i1.7.
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This study was designed to evaluate the effects of melatonin and Allium sativum (garlic) on dibutyl phthalate (DBP) influence on spermiogram of rabbit bucks. Forty two (42) rabbit bucks were used for this study, bucks were randomly divided into 7 groups of 6 bucks each. Group A was administered olive oil for 16 weeks, group B (olive oil + DBP for 16 weeks), group C (melatonin for 8 weeks, then olive oil + DBP for another 8 weeks), group D (garlic for 8 weeks, then olive oil + DBP for another 8 weeks), group E (olive oil + DBP for 8 weeks, then melatonin for another 8 week), group F (olive oil + DBP for 8 weeks, then garlic for another 8 weeks) and group G (olive oil + DBP for 8 weeks, then melatonin and garlic for another 8 weeks). The observation period lasted for 120 days, during which semen samples were collected weekly between the hours of 8.00 am to 10.00 am using artificial vagina (AV).There were significant differences (P<0.05) in mean reaction time, semen volume, sperm motility, sperm concentration, percentage live spermatozoa and percentage abnormal morphology between DBP exposed groups and treatment groups. Conclusion, DBP has adverse effects on spermiogram but administration of melatonin and garlic has promising protective effects than therapeutic effect on rabbit bucks.
Key words: Melatonin; Allium sativum; Dibutyl phthalate; Spermiogram; Rabbit Bucks
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Alam, Mohammad Shah, Seiichiroh Ohsako, Takashi Matsuwaki, Xiao Bo Zhu, Naoki Tsunekawa, Yoshiakira Kanai, Hideko Sone, Chiharu Tohyama, and Masamichi Kurohmaru. "Induction of spermatogenic cell apoptosis in prepubertal rat testes irrespective of testicular steroidogenesis: a possible estrogenic effect of di(n-butyl) phthalate." REPRODUCTION 139, no. 2 (February 2010): 427–37. http://dx.doi.org/10.1530/rep-09-0226.
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Although di(n-butyl) phthalate (DBP), a suspected endocrine disruptor, induces testicular atrophy in prepubertal male rats, whether it exerts estrogenic activity in vivo remains a matter of debate. In the present study, we explored the estrogenic potency of DBP using 3-week-old male rats, and then examined the relationship between estrogen-induced spermatogenic cell apoptosis and testicular steroidogenesis. Daily exposure to DBP for 7 days caused testicular atrophy due to loss of spermatogenic cells, whereas testicular steroidogenesis was almost the same with the control values. A single exposure of DBP decreased testicular steroidogenesis in addition to decreasing the level of serum LH at 3 h after DBP treatment, with an extremely high incidence of apoptotic spermatogenic cells at 6 h after administration. To elucidate the estrogenic activity of DBP, we carried out an inhibition study using pure antiestrogen ICI 182,780 (ICI) in a model of spermatogenic cell apoptosis induced by DBP or estradial-3-benzoate (EB). Although both the DBP- and EB-treated groups showed a significant increase in spermatogenic cell apoptosis, ICI pretreatment significantly decreased the number of apoptotic spermatogenic cells in these two groups. In contrast, testicular steroidogenesis and serum FSH were significantly reduced in all the treated groups, even in the DBP+ICI and EB+ICI groups. Taken together, these findings led us to conclude that estrogenic compounds such as DBP and EB induce spermatogenic cell apoptosis in prepubertal rats, probably by activating estrogen receptors in testis, and that reduction in testicular steroidogenic function induced by estrogenic compounds is not associated with spermatogenic cell apoptosis.
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Uchida, Daisuke, Ryo Kido, Hiroo Kawarazaki, Masaru Murasawa, Ayami Ando, Shouichi Fujimoto, Kunitoshi Iseki, et al. "Lower Diastolic Blood Pressure was Associated with Higher Incidence of Chronic Kidney Disease in the General Population Only in those Using Antihypertensive Medications." Kidney and Blood Pressure Research 44, no. 5 (2019): 973–83. http://dx.doi.org/10.1159/000501828.
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Background/Aims: The association of diastolic blood pressure (DBP) with incidence of chronic kidney disease (CKD) in the general population is not well examined. Methods: Using national health check-up database from 2008 to 2011 in the general Japanese population aged 39–74 years, we evaluated the association between DBP and incidence of CKD 2 years later in 127,954 participants without CKD. DBP was categorized by every 5 mm Hg from the lowest (<60 mm Hg) to the highest category (>100 mm Hg) and was further stratified into those with and without antihypertensive medications (BP meds). We calculated the OR for estimating adjusted risk of incident CKD using logistic regression model. Results: Participants were 62% female and 25.9% with BP meds, mean age of 76 years with estimated glomerular filtration rate of 78.2 ± 13.4 and DBP of 76 ± 11 mm Hg. Two years later, 12,379 (9.7%) developed CKD. Compared to DBP 60–64 mm Hg without BP meds as reference, multivariate analysis showed no difference in CKD risk at any DBP category among those without BP meds. However, in those with BP meds, risk increased according to lower DBP from 95 to 60 mm Hg (p for trend 0.05) with OR 1.51 (95% CI 1.14–1.99) in DBP <60 mm Hg. In subgroup analysis within those with or without BP meds, CKD risk was lower at higher DBP (p for trend 0.02) only in those without BP meds. Conclusion: Lower DBP was associated with higher risk of incident CKD only in the general population taking antihypertensive medication.
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Augustyn, Marilyn, Ellen Johnson Silver, Nathan Blum, Pamela High, Nancy Roizen, and Ruth E. K. Stein. "DBP Evaluations in DBPNet Sites." Journal of Developmental & Behavioral Pediatrics 41, no. 1 (January 2020): 23–30. http://dx.doi.org/10.1097/dbp.0000000000000710.
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Nys, Y., R. Bouillon, H. Van Baelen, and J. Williams. "Ontogeny and oestradiol dependence of vitamin D-binding protein blood levels in chickens." Journal of Endocrinology 108, no. 1 (January 1986): 81–87. http://dx.doi.org/10.1677/joe.0.1080081.
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ABSTRACT The concentration of 25-hydroxyvitamin D3-binding protein (DBP) was measured, by immunodiffusion, in the blood of chickens from embryonic stages to sexual maturity. Low levels of DBP and 1,25-(OH)2D3 were detectable in the blood of chick embryos from the 12th and 17th day of incubation respectively and stayed at the same low levels until hatching. The blood concentration of DBP doubled between the 1st and 5th days of life, then increased slowly and reached the mean level of the adult male at 7–8 weeks of age. The concentration of DBP was independent of vitamin D status in growing chickens. A large increase was observed in DBP blood levels in hens just before sexual maturity. This change, and those observed in moulting hens, followed the variations in plasma concentrations of oestradiol more closely than those of progesterone or testosterone. Moreover, a large increase in plasma DBP levels was induced in immature chickens by oestradiol (0·5 mg/day), but not by testosterone or progesterone. Finally, the experimental suppression of egg shell formation and the associated decrease in 1,25-(OH)2D3 plasma levels had no effect on plasma DBP concentrations. However, 1,25-(OH)2D3 and DBP levels were higher in hens laying shell-less eggs than in immature pullets. The increases in DBP levels at hatching, in immature pullets treated with oestrogens, in hens laying uncalcified eggs and at the onset of egg production were associated with increases in 1,25-(OH)2D3, suggesting a relationship between the levels of DBP and 1,25-(OH)2D3 in the blood. J. Endocr. (1986) 108, 81–87
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Xiong, Ze, Yuyao Zeng, Jiafeng Zhou, Ruonan Shu, Xiaoxian Xie, and Zhengwei Fu. "Exposure to dibutyl phthalate impairs lipid metabolism and causes inflammation via disturbing microbiota-related gut–liver axis." Acta Biochimica et Biophysica Sinica 52, no. 12 (November 10, 2020): 1382–93. http://dx.doi.org/10.1093/abbs/gmaa128.
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Abstract Dibutyl phthalate (DBP), a kind of typical environmental pollutant, is widely used as plasticizers, and its neurotoxicity and developmental toxicity have been found in recent years. However, whether oral DBP exposure will affect the homeostasis of gut microbiota and its adverse response in liver of mammalians remain unclear. In the present study, 10-week experimental cycles of vehicle or DBP (0.1 and 1 mg/kg) were given to 6-week-old C57BL/6J mice by oral gavage. Our results revealed that the body weight of mice was increased after exposure to both low and high doses of DBP. The serum levels of hepatic triglyceride and total cholesterol were significantly increased in response to both doses of DBP. In addition, some pivotal genes related to lipogenesis were also increased in liver at the mRNA level. Evaluation of gut microbiota by 16S rRNA sequencing technology showed that 0.1 mg/kg DBP exposure significantly affected gut microbiota at the phylum and genus levels. Moreover, DBP exposure decreased mucus secretion and caused inflammation in the gut, leading to the impairment of intestinal barrier function. Exposure to DBP inhibited the expression of peroxisome proliferator-activated receptor-γ and activated the expression of nuclear factor kappa B. In addition, DBP exposure increased the level of lipopolysaccharide in serum, and increased the expression of toll-like receptor 4 and the levels of inflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha, in the liver. These results indicated that exposure to DBP disturbed the homeostasis of gut microbiota, induced hepatic lipid metabolism disorder, and caused liver inflammation in mice via the related gut–liver axis signaling pathways.
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Wang, Yi, Yan-Jiao Wang, Jun-Kun Zhan, Zhi-Yong Tang, Wu Huang, Pan Tan, Shan Gao, Cai-Li Ma, Zai-Jin Jian, and You-Shuo Liu. "Vitamin D Binding Protein Affects the Correlation of 25(OH)D and Frailty in the Older Men." International Journal of Endocrinology 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/543783.
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Vitamin D binding protein (DBP) may alter the biologic activity of 25-hydroxyvitamin D [25(OH)D]. The objective of our present study was to determine the joint effect of serum 25(OH)D and DBP on the risk of frailty. Five hundred sixteen male participants aged 70 years or older were recruited in Changsha city and its surrounding area in Hunan province of China. Frailty was defined as the presence of at least three of the five following criteria: weakness, low physical activity, slow walking speed, exhaustion, and weight loss. Multivariate linear regression analysis was performed to assess the relationship between 25(OH)D and DBP levels. Odds ratios (ORs) for frailty were evaluated across quartiles of 25(OH)D and DBP levels, adjusted age, education, and body mass index. The results showed that participants in the lowest quartile of 25(OH)D and the highest quartile of DBP levels, the lowest quartile of 25(OH)D and the lowest quartile of DBP levels, and those in the the lower quartile of 25(OH)D and lowest quartile of DBP levels had significantly higher OR of being frail compared with those in the highest quartile of 25(OH)D and lowest quartile of DBP, with OR of 3.18 (95% CI: 1.46–4.56,P<0.05), 2.63 (95% CI: 1.31–3.68,P<0.01), and 2.52 (95% CI: 1.22–3.52,P<0.05), respectively. The results indicate that the joint effect of serum 25(OH)D and DBP levels is associated with the risk of frailty, and serum DBP levels affects 25(OH)D-frailty relationship in the older men.
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Majeed, Khalid Abdul, Muhammad Shahbaz Yousaf, Muhammad Sajid Tahir, Aamir Riaz Khan, Suliman Khan, Abdullah Arif Saeed, and Habib Rehman. "Effects of Subacute Exposure of Dibutyl Phthalate on the Homeostatic Model Assessment, Thyroid Function, and Redox Status in Rats." BioMed Research International 2021 (August 4, 2021): 1–8. http://dx.doi.org/10.1155/2021/5521516.
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Dibutyl phthalate is an endocrine disruptor used in a wide range of industrial and agriculture applications. The present study focuses on elucidating the effect of subacute exposure (4-weeks) of DBP on insulin and its sensitivity indexes, oxidative status, thyroid function, energy metabolites, serum biochemistry, and anthropometry in rats. A total of 64 rats were divided into 4 treatment groups as mg DBP/Kg body weight per day: (a) 0 mg/Kg (control), (b) 10 mg/Kg (DBP-10), (c) 50 mg/Kg (DBP-50), and (d) 100 mg/Kg (DBP-100). The rats in each treatment ( n = 16 ) were further divided into male ( n = 8 ) and female ( n = 8 ) rats for studying treatment and gender interactions. Intraperitoneal glucose tolerance test (IPGTT) was performed on the 21st day. Anthropometry, nutritional determinants, fasting plasma glucose, fasting plasma insulin, homeostatic model assessment (HOMA), thyroid hormones, energy metabolites, and oxidative status were studied during the experimental period. Two-way ANOVA was used to analyze the data ( p < 0.05 ). Tukey’s posthoc test was used for pair-wise comparisons. DBP increased body weight gain and feed efficiency in an inverted nonmonotonic U -shaped fashion. Hyperglycemia and increased blood glucose area under the curve were observed in DBP-100 at 120 minutes in IPGTT. The HOMA also showed a linear monotonic contrast. Thyroxin decreased significantly in the DBP-100 rats, whereas malondialdehyde, nonesterified fatty acids, and beta hydroxyl butyrate were increased with the DBP treatments. In conclusion, DBP could be attributed to the development of hyperglycemia and insulin resistance in rats. Further investigations into the lipid peroxidation pathways can improve our understanding of the mechanisms involved in metabolic disruption.
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Staley Shumaker, B., G. Wei Qi, S. Amano, A. Nolty, and M. Harrington. "C-09 Diastolic Blood Pressure and Executive Function in Healthy Older Adults." Archives of Clinical Neuropsychology 34, no. 6 (July 25, 2019): 1036. http://dx.doi.org/10.1093/arclin/acz034.171.
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Abstract Objective Our aim was to investigate the effect of elevated diastolic blood pressure (DBP) within normal blood pressure range (NBPR) on an executive functioning task (Stroop C) in a cognitively healthy, high functioning, older adult population. Method Archival data at Huntington Medical Research Institutes provided 35 cognitively healthy, high functioning adults from 63 to 89 years of age (M = 76, SD = 7.0). The majority were female and Caucasian, and had college or higher degrees. A general linear model (GLM) regression analysis was performed to determine if the Stroop C Interference z score would be predicted by DBP NBPR when controlling for age, sex, education level, and ApoE4 genotype. Results The regression model for DBP NBPR on Stroop Interference z scores was significant, F(5, 29) = 1.56, p < .05, with increased DBP NBPR associated with decreased Stroop Interference z scores (slower completion time). Conclusions Increased DBP NBPR was negatively associated with executive functioning as indicated by Stroop C Interference performance, such that individuals with slower completion times had elevated DBP NBPR measurements. These results suggest that increased DBP NBPR may play a role in the reduction of executive functioning performance in cognitively healthy older adults and are consistent with prior findings identifying increased DBP as a risk factor for neurodegeneration (den Heijer et al., 2005; Kennelly et al., 2009). The current study highlights the need for increased attention to the role of DBP in neurodegeneration.
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Lourenço, ACS, C. Gomes, AC Boareto, RP Mueller, F. Nihi, LF Andrade, ES Trindade, et al. "Influence of oily vehicles on fetal testis and lipid profile of rats exposed to di-butyl phthalate." Human & Experimental Toxicology 33, no. 1 (March 27, 2013): 54–63. http://dx.doi.org/10.1177/0960327112474847.
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It has been hypothesized that oils containing high levels of omega-3 polyunsaturated fatty acids, such as canola and fish oil, could counteract some of the adverse effects induced by phthalates. In the present study, the influence of different oily vehicles on di-butyl phthalate (DBP)-induced testicular toxicity and lipid profile was investigated. Pregnant Wistar rats were treated by oral gavage from gestation days 13 to 20 with DBP (500 mg/kg/day) diluted in three different vehicles: corn, canola or fish oil. Male fetuses were analyzed on gestation day 20. DBP exposure lowered intratesticular testosterone levels and anogenital distance, regardless of the vehicle used. The percentage of seminiferous cords containing multinucleated gonocytes and cord diameter was increased in DBP-exposed groups, compared with vehicle controls, with no difference between the three DBP-exposed groups. Clustering of Leydig cells was seen in all DBP groups. Lipid profile indicated that administration of canola and fish oil can increase the content of omega-3 fatty acids in rat testis. However, content of omega-3 was diminished in DBP-treated groups. Overall, our results indicate that different oily vehicles did not alter fetal rat testicular toxicity induced by a high DBP dose.
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Tringali, Steven, Charles William Oberer, and Jian Huang. "Low Diastolic Blood Pressure as a Risk for All-Cause Mortality in VA Patients." International Journal of Hypertension 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/178780.
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Background. A paradoxical increase in cardiovascular events has been reported with intensively lowering diastolic blood pressure (DBP). This J-curve phenomenon has challenged the aggressive lowering of blood pressure, especially in patients with coronary artery disease.Objective. Our objective was to study the effects of low DBP on mortality and determine a threshold for which DBP should not be lowered beyond.Methods. We evaluated a two-year cross-section of primary care veteran patients, from 45 to 85 years of age. Receiver operating characteristics (ROC) were employed to establish an optimal cut-off point for DBP. Propensity-score matching and multivariate logistic regression were used to control for confounders. All-cause mortality was the primary outcome.Results. 14,270 patients were studied. An ROC curve found a threshold value of DBP 70 mmHg had the greatest association with mortality (P<0.001). 49% of patients had a DBP of 70 mmHg or less. Using a propensity-matched multivariate logistic regression, odds ratio for all-cause mortality in subjects with a DBP less than 70 mmHg was 1.5 (95% CI 1.3–1.8).Conclusions. Reduction of DBP below 70 mmHg is associated with increased all-cause mortality. Hypertension guidelines should include a minimum blood pressure target.
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Bhan, Ishir. "Vitamin D Binding Protein and Bone Health." International Journal of Endocrinology 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/561214.
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Vitamin D binding protein (DBP) is the major carrier protein of 25-hydroxyvitamin D (25(OH) D) in the circulation, where it may serve roles in maintaining stable levels during times of decreased 25(OH) availability and in regulating delivery of 25(OH) D to target tissues. Several genetic polymorphisms of DBP have been described that lead to phenotypic changes in the protein that may affect affinity, activity, and concentration. These polymorphisms have been linked with alterations in bone density in several populations. One of the mechanisms by which DBP may alter bone health involves regulating vitamin D bioavailability. DBP-bound vitamin is thought to be relatively unavailable to target tissues, and thus alterations in DBP levels or affinity could lead to changes in vitamin D bioactivity. As a result, functional vitamin D status may differ greatly between individuals with similar total 25(OH) D levels. Additionally, DBP may have independent roles on macrophage and osteoclast activation. This review will summarize recent findings about DBP with respect to measures of bone density and health.
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Gauzzi, Maria Cristina. "Vitamin D-binding protein and multiple sclerosis: Evidence, controversies, and needs." Multiple Sclerosis Journal 24, no. 12 (August 16, 2018): 1526–35. http://dx.doi.org/10.1177/1352458518792433.
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The vitamin D-binding protein (DBP) occupies a key node in the regulation of the vitamin D system. Being the main plasma carrier of vitamin D metabolites, it regulates their stability and bioavailability. However, DBP is also a multifunctional protein with roles in the organism’s actin scavenging system and immunomodulation. All these activities may affect multiple sclerosis (MS) pathophysiology. DBP can be measured in blood and cerebrospinal fluid, body fluids that have been investigated as sources of accessible biomarkers of MS. Yet, available data on DBP expression and function in MS are scattered and somewhat controversial. Aims of this review are to summarize current evidence from studies on DBP in MS patients, to discuss possible shortcomings and to highlight key points that need to be addressed to gain deeper insight into the role of DBP in MS.
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Yamaguchi, Shun, Shigeru Mitsui, Lily Yan, Kazuhiro Yagita, Shigeru Miyake, and Hitoshi Okamura. "Role of DBP in the Circadian Oscillatory Mechanism." Molecular and Cellular Biology 20, no. 13 (July 1, 2000): 4773–81. http://dx.doi.org/10.1128/mcb.20.13.4773-4781.2000.
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ABSTRACT Transcript levels of DBP, a member of the PAR leucine zipper transcription factor family, exhibit a robust rhythm in suprachiasmatic nuclei, the mammalian circadian center. Here we report that DBP is able to activate the promoter of a putative clock oscillating gene,mPer1, by directly binding to the mPer1promoter. The mPer1 promoter is cooperatively activated by DBP and CLOCK-BMAL1. On the other hand, dbp transcription is activated by CLOCK-BMAL1 through E-boxes and inhibited by the mPER and mCRY proteins, as is the case for mPer1. Thus, a clock-controlled dbp gene may play an important role in central clock oscillation.
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Isa, M. I. N., and A. K. Arof. "Salicylic Acid and Dibuthyl Phatalate (DBP) Interaction in PMMA-Based Gel Electrolytes." Materials Science Forum 517 (June 2006): 294–0. http://dx.doi.org/10.4028/www.scientific.net/msf.517.294.
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A gel electrolyte system was prepared by dissolving poly(methyl methacrylate) (PMMA) in ethylene carbonate (EC) and propylene carbonate (PC) doped with salicylic acid (SA) and plasticized with dibutyl phthalate (DBP). The composition of the electrolyte was 35 wt% EC-30 wt% PC-5 wt% SA-5wt% DBP-25 wt% PMMA. The presence of a hump at ~760 cm-1 and a shoulder at 1155 cm-1 in the spectrum of SA-DBP indicate the protonation of DBP. The effect of these bands can also be observed in the spectrum of the gel. Hence, SA has dissociated producing H+ which then interacts datively at the oxygen sites of DBP.
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Landry, JS, D. Croitoru, and D. Menzies. "Validation des codes de diagnostic de la CIM-9 pour la dysplasie bronchopulmonaire dans les bases de données de la Régie de l'assurance-maladie du Québec." Maladies chroniques et blessures au Canada 33, no. 1 (December 2012): 54–60. http://dx.doi.org/10.24095/hpcdp.33.1.06f.
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Introduction La dysplasie bronchopulmonaire (DBP) est une maladie respiratoire chronique causée par une lésion pulmonaire néonatale. Cette étude a pour objet de valider l'utilisation des codes de diagnostic de la CIM-9 correspondant à la DBP dans les bases de données administratives pour déterminer s'ils peuvent être employés dans les analyses sur l'utilisation du système de soins de santé. Méthodologie Le processus de validation a fait appel à une cohorte rétrospective composée de nouveau-nés prématurés, ayant présenté ou non des complications respiratoires, qui avaient été admis à l'Hôpital de Montréal pour enfants, à Montréal (Québec), entre 1983 et 1992. Les sujets atteints de DBP ont été identifiés au moyen des codes de diagnostic de la CIM-9 dans les bases de données administratives provinciales (services médicaux et MED-ECHO), puis comparés à des sujets atteints d'une DBP confirmée dans la cohorte de validation. Nous avons examiné la concordance des données et avons estimé la sensibilité et la spécificité associées à l'utilisation de ces codes de diagnostic pour la DBP. Résultats Les cas dits « vrais positifs » de DBP et les cas dits « faux négatifs » de DBP ne présentaient pas de différences significatives selon l'âge gestationnel, le poids à la naissance et le score d'Apgar. L'âge gestationnel associé aux cas dits « faux positifs » de DBP était considérablement inférieur à celui des vrais négatifs. L'utilisation de codes de diagnostic de la CIM-9 pour la DBP a été associée à une spécificité se situant entre 97,6 % et 98,0 %. La sensibilité, plus faible, se situait à 45,0 % et à 52,4 % pour les bases de données sur les services médicaux et MED-ECHO, respectivement. Il est arrivé plus fréquemment que les cas légers de DBP ne soient pas décelés que les cas plus graves. Conclusion Le degré de spécificité des codes de diagnostic de la CIM-9 pour la DBP dans les bases de données de la Régie de l'assurance-maladie du Québec est suffisamment élevé pour permettre l'utilisation de ces codes de façon systématique. La sensibilité plus faible en ce qui concerne les cas légers se soldera probablement par une sous-estimation des répercussions de la DBP sur l'utilisation à long terme du système de soins de santé par les nouveau-nés prématurés.