Inhibition of aflatoxin B(1) biosynthesis in Aspergillus flavus by anthocyanidins and related flavonoids.   总被引：3，自引：0，他引：3  

R A Norton 《Journal of agricultural and food chemistry》1999,47(3):1230-1235

Anthocyanidins and precursors or related flavonoids were tested at concentrations from 0.3 to 9.7 mM ( approximately 0.1-3.0 mg/mL) for activity against growth and aflatoxin B(1) biosynthesis by Aspergillus flavus Link:Fr. NRRL 3357. Aflatoxin B(1) production was inhibited by all anthocyanidins tested, and 3-hydroxy compounds were more active than 3-deoxy forms. Monoglycosides of cyanidin were 40% less inhibitory than the aglycon, whereas a monoglucoside and a diglucoside of pelargonidin were 80 and 5%, respectively, as active as the aglycon. Of eight flavonoids tested, only kaempferol was moderately active, whereas luteolin and catechin were weakly inhibitory. Binary combinations of delphinidin and three other aflatoxin inhibitors acted independently of each other. Results with an aflatoxin pathway mutant indicated that anthocyanidin inhibition occurred before norsolorinic acid synthesis.  相似文献   

A 100,000-year periodicity in the accretion rate of interplanetary dust     

SJ Kortenkamp  SF Dermott 《Science (New York, N.Y.)》1998,280(5365):874-876

Numerical modeling of the orbital evolution of interplanetary dust particles revealed that, over the past 1.2 million years, the rate of accretion of dust by Earth has varied by a factor of 2 to 3. These variations display a 100,000-year periodicity and are anticorrelated with Earth's changing orbital eccentricity. Extraterrestrial helium-3 concentrations in a deep-sea sediment core display a similar periodicity but are 50,000 years out of phase with the predicted variations. Also, because collisions between large bodies in the asteroid belt are inevitable, it is expected that large-amplitude stochastic variations on 10(7)- to 10(8)-year time scales would be superimposed on the 10(5)-year periodic variations.  相似文献   

Medical and surgical management of benign prostatic hyperplasia, diskospondylitis, and penile paresis in an ocelot.     

T M Norton  W H Adams  G V Kollias  V L Clyde 《Journal of the American Veterinary Medical Association》1990,197(5):630-632

Benign prostatic hyperplasia, diskospondylitis at the T13-L1 intervertebral disk space, and penile paresis were diagnosed in a 16-year-old male ocelot. Treatment consisted of castration for the benign prostatic hyperplasia and long-term administration of antibiotics for the diskospondylitis. On physical examination 8 weeks after initial referral, the prostate gland was no longer palpable and could not be visualized radiographically or ultrasonographically. The diskospondylitis lesion was found to be healing, on the basis of radiographic results.  相似文献   

Rooting stem cuttings of Chinese chestnut     

A.G. Hunter  J.D. Norton 《Scientia Horticulturae》1985,26(1):43-45

Rooting of Chinese chestnut (Castanea mollissima Blume.) stem cuttings following treatment with indole-3-butyric acid (IBA) was investigated. Tip and basal cutting from vigorous epicormic shoots and terminal shoots with 2–3 cm of the previous year's wood were taken from mature regions of trees approximately 40 years of age. Cuttings were dipped for 5 s in an aqueous solution of either 3 or 6 g l^?1 IBA. Rooting occurred only in the basal softwood cuttings. Average rooting of 33.5, 5.0 and 1.6% for ‘AU-Leader’, ‘AU-Homestead’ and ‘AU-Cropper’, respectively, was obtained using the 3 g l^?1 IBA solution, and 35.0, 6.7 and 3.3%, respectively, using the 6 g l^?1 IBA solution.  相似文献   

Extraction of formazan from tetrazolium-treated Pisum sativum L. seeds after soaking treatments     

C.R. Norton 《Scientia Horticulturae》1985,26(2):99-103

Soaking-injury in seeds of Pisum sativum L. was determined using the triphenyl tetrazolium chloride reduction method after 0–120 h of soaking. The spectrophotometric determination of absorbance of acetone extracts was at 500 nm. This minimised confusion with the chlorophyll peak. Germination and absorbance of seed extracts declined with period of soaking.  相似文献   

Raw mung beans as a protein source for bred gilts     

W G Luce  C V Maxwell  D S Buchanan  R O Bates  M D Woltmann  S A Norton  G N Dietz 《Journal of animal science》1989,67(2):329-333

A study involving 546 crossbred gilts from six seasons was conducted to evaluate raw mung beans as a partial replacement for soybean meal in diets for gilts during gestation. Gilts were randomly allotted to either a control sorghum grain-soybean meal diet or a diet in which a portion of the soybean meal was replaced with mung beans. In the first three seasons, gilts were fed diets in which the protein supplement was totally soybean meal or 89% mung beans (high level) and 11% soybean meal. In the last three seasons the level of mung beans in the supplemental protein was reduced to 61% mung beans with 39% soybean meal (moderate level). Feeding the high level of mung beans decreased (P less than .05) weight gain during gestation and reduced (P less than .05) weight loss during lactation compared with gilts fed the control diet or the moderate level of mung beans. Little difference was noted in litter size at birth, but litter size at 21 d for gilts fed moderate levels of mung beans was less (P less than .05) than for gilts fed the control diet or the high level of mung beans. Little difference was noted in survival rate to 21 or 42 d or individual and litter weights at birth and 21 d. Pig and litter weights at 42 d, however were reduced in gilts fed the high level of mung beans (P less than .05 and P less than .10, respectively) compared with the control diet.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Cold resistance and environmental temperature preference in diarrheic piglets     

R K Balsbaugh  S E Curtis  R C Meyer  H W Norton 《Journal of animal science》1986,62(2):315-326

Piglets aged 12 to 72 h in which diarrhea had been induced by enteric Escherichia coli infection or sucrose gavage were studied with respect to cold resistance and thermal-circulation index in a 90-min test in a 6 C environment (Exp. 1) and free-choice environmental-temperature preference during a 60-min test in a 24 to 44 C thermocline (Exp. 2). In Exp. 1, diarrhea lowered the piglet's ability to maintain body temperature during the cold test. Also, diarrheic piglets tended to have lower thermal circulation index values at the end of the cold test, indicative of a greater vasoconstrictive response to the cold environment. In Exp. 2, mean preferred environmental temperatures were 35.7, 34.9 and 34.5 C, respectively, for piglets in sham-control, E. coli-infected and sucrose-gavaged groups. For reason(s) still unknown, diarrheic piglets did not choose to locate themselves in a warmer niche than did normal piglets; in fact, they did the opposite. Results of the two experiments indicate that diarrheic neonatal piglets need even more attention and care in terms of the thermal environment than do healthy ones.  相似文献   

Use of injectable vitamin E and selenium-vitamin E emulsion in ewes and suckling lambs to prevent nutritional muscular dystrophy     

S A Norton  F D McCarthy 《Journal of animal science》1986,62(2):497-508

Forty-eight Blackbelly X Dorset, 27 Finnish, 26 Finnish X Dorset, 28 Rambouillet and 8 Dorset Suffolk-sired lambs were used in this experiment. Three weeks before lambing, one-half of the ewes received a selenium emulsion (Se-E) containing .05 mg selenium and 3.7 IU of vitamin E/kg body weight (BW). A 2 X 3 X 2 factorial arrangement was used; lambs from either treated or nontreated ewes were randomly assigned irrespective of breed to one of six treatment combinations consisting of 0 or .025 mg/kg BW selenium (Se) injected at birth or two .025 mg/kg BW Se injections, one at birth and one 2 to 3 wk later, and two levels of injectable Vitamin E (E; 0 and 100 IU) given at birth. Both lambs and ewes were provided access to 75% concentrate diets supplemented with Se and E at recommended NRC levels. Plasma activity of creatine phosphokinase (CPK) was highest at 1 d of age and exhibited decreases (P less than .001) over time. In lambs, the E injection tended to decrease plasma activity of CPK. Plasma glutathione peroxidase activity was lowest at 1 d of age and increased over the course of the experiment but was unaffected by treatments (P less than .05). Plasma tocopherol concentration decreased (P less than .01) with time, with E therapy tending to increase tocopherol concentration. Differences in mean plasma tocopherol concentrations among breeds were also observed (P less than .01). Selenium concentration increased over time and with the E injection (P less than .01). An interaction between ewe and lamb Se-E treatments also was observed (P less than .10), with nontreated lambs from nontreated ewes exhibiting lower Se concentrations than treated lambs from injected ewes. An increase in lamb plasma Se concentration was noted in response to Se-E treatments (P less than .001). In the ewes, plasma tocopherol concentration was lower while Se concentration was higher at 18 d than at 1 d postpartum (P less than .01 and P less than .001, respectively). Milk Se concentration was lower at 18 d than at 1 d (P less than .001) and was higher (P less than .10) in Se-E-treated ewes.  相似文献   

Abnormal coagulation factor VIII transcript in a Tennessee Walking Horse colt with hemophilia A          下载免费PDF全文

Elaine M. Norton  Anne A. Wooldridge  Allison J. Stewart  Layla Cusimano  Dean D. Schwartz  Calvin M. Johnson  Mary K. Boudreaux  Pete W. Christopherson 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(1):96-102

Hemophilia A is an X‐chromosome‐linked disorder caused by a deficiency in factor VIII (FVIII). Although foals have been diagnosed with hemophilia A based on deficiency in FVIII activity, causative gene mutations have not been identified. The genomic DNA and cDNA encoding FVIII of a Tennesee Walking Horse colt affected with hemophilia A and the genomic DNA of his dam and a normal unrelated horse were analyzed with no splice site or coding sequence abnormalities identified in any of the horses. Polymerase chain reactions (PCR) were then performed on hepatic cDNA from the affected colt and an unrelated normal horse, and no product was obtained for the sequence between and including exon 1 and exon 2 in the affected colt. Based on these results, suspected mutations were identified in the noncoding region of FVIII (intron 1), and genomic sequencing of intron 1 in the dam and the affected colt suggested maternal inheritance.  相似文献   

The occurrence of Eimeria weybridgensis and other species of coccidia in lambs in England and Wales.     

J Catchpole  C C Norton  L P Joyner 《The British veterinary journal》1975,131(4):392-401

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