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81.
Maurice Jay Bernard Voirin Aurangzeb Hasan Jean-François Gonnet Marie-Rose Viricel 《Biochemical Systematics and Ecology》1980,8(2):127-132
A survey of the leaves and flowers of 62 representatives of the tribe Loteae (Leguminosae) showed the presence of several classes of flavonoids: flavonol 7-methyl ethers (rhamnocitrin, rhamnetin), 8-O-substituted flavonols (gossypetin, limocitrin, sexangularetin, corniculatusin), 3′,4′,5′-tri-O-substituted flavonols (myricetin, mearnsetin, syringetin, laricitrin), proanthocyanidins and flavone-C-glycosides. The trisubstitution of the B-ring and the 8-O-substitution of the A-ring allow the definition of a major group including the genera Dorycnium, Bonjeania, Lotus and Tetragonolobus. The presence of proanthocyanidins and 7-O-methylation determine a second group consisting of the genus Anthyllis. Finally, Securigera, on the basis of its flavonoid chemistry, appears to be rather remote from other members of the tribe. 相似文献
82.
Tae Kyung Han 《Journal of Exercise Nutrition & Biochemistry》2013,17(4):209-217
The purpose of the current study was to investigate whether or not the FABP2 gene polymorphism modulated obesity indices, hemodynamic factor, blood lipid factor, and insulin resistance markers through 12-week aerobic exercise training in abdominal obesity group of Korean mid-life women. A total of 243 abdominally obese subjects of Korean mid-life women voluntarily participated in aerobic exercise training program for 12 weeks. Polymerase Chain Reaction with Restriction Fragment Length Polymorphism (PCR-RFLP) assay was used to assess the FABP2 genotype of the participants (117 of AA homozygotes, 100 of AT heterozygotes, 26 of TT homozygotes). Prior to the participation of the exercise training program, baseline obesity indices, hemodynamic factor, blood lipid factor, and insulin resistance markers were measured. All the measurements were replicated following the 12-week aerobic exercise training program, and then the following results were found. After 12-week aerobic exercise training program, wild type (Ala54Ala) and mutant type (Ala54Thr+Thr54Thr) significantly decreased weight (P > .001), BMI (P > .001), %bf (P > .001), waist circumference (P > .001), WHR (P > .001), muscle mass (wild type p < .022; mutant type P > .001), RHR (P > .001), viseceral adipose area (wild type p < .005; mutant type P > .001), subcutaneous area (P > .001), insulin (wild type p < .005; mutant type P > .001) and significantly increased VO2max (P > .001). And wild type significantly decresed NEFA (P > .05), glucose (P > .05), OGTT 120min glucose (P > .05) and significantly increased HDLC (p > .005). Mutant type significantly decreased SBP (P > .001), DBP (P > .01), TC (P > .01), LPL (P > .05), LDL (P > .001), HOMA index (P > .01). The result of the present study represents that regular aerobic exercise training may beneficially prevent obesity index, blood pressure, blood lipids and insulin resistance markers independent of FABP Ala54Thr wild type and mutant type. 相似文献
83.
BackgroundResearch to date suggests that nickel affects not only the metabolism of vitamin B12 but also folates and thus may affect hematopoiesis processes.ObjectiveThe aim of the study was to examine the relationship of nickel (Ni) status to red blood cell (RBC) parameters and serum vitamin B12, folate and homocysteine concentrations in the course of normal pregnancy and in pregnant women with anemia.MethodsThe study included fifty-three pregnant women recruited to the study from the Lower Silesia region of Poland, 17 % of whom developed anemia. Nickel concentration was determined in urine, whole blood and food samples by atomic absorption spectrometry. At the same time as the food and urine samples were taken, blood was also collected for the determination of RBC parameters and serum vitamin B12, homocysteine and folate concentrations.ResultsThe median reported Ni intake, and the urinary and whole blood nickel contents for the studied pregnant women for the first trimester were respectively – 162.46 μg/day, 3.98 μg/L and 3.32 μg/L; for the second trimester – 110.48 μg/day, 6.86 μg/L and 1.04 μg/L; and for the third trimester – 132.20 μg/day, 3.41 μg/L and 0.70 μg/L. With regard to Ni concentration in whole blood (p = 0.0204) and in urine (p = 0.0003), the differences in the values for individual trimesters were statistically significant. The whole blood Ni level was significantly higher (9.28 vs 3.62 μg/L, p = 0.0114), while the concentration of homosysteine was significantly lower (4.09 vs 5.04 μmol/L, p = 0.0165) in pregnant women with anemia compared to those without anemia. The whole blood Ni concentration was negatively correlated with almost all RBC parameters in non-anemic pregnant women.ConclusionsNi status changes with the development of normal pregnancy, and in the case of anemia, an increase in Ni concentration in whole blood is observed. The demonstrated correlations between the Ni status in pregnant women and RBC parameters as well as serum vitamin B12 and folate concentrations suggest that nickel is associated with the methionine–folate cycle, iron homeostasis and bacterial synthesis of vitamin B12 in humans. 相似文献
84.
85.
桔黄赛多孢菌Scedosporium aurantiacum是慢性肺病患者的常见呼吸道定植菌,在免疫缺陷人群中可引起侵袭性感染,致死率高,但由于致病机理不明,目前仍然缺乏有效的防控手段。我们在前期研究中,通过差异蛋白组学及酶工程技术发现分泌胰蛋白酶是桔黄赛多孢菌的潜在毒力因子,目前对这种蛋白酶的遗传信息、结构及致病机制并不清楚。本研究用Superdex S-200分子筛和DEAE-Sepharose离子交换两种填料将这种蛋白酶分离纯化出来,通过酶谱验证了纯化效果。进一步研究发现,这种胰蛋白酶对bFSR、bLSTR和bEKK 3种底物的水解性能最佳,对zFR和bzLR的水解性能最差。酶解最快的反应所对应的Km为6.09μmol/L,Vmax为13.01μmol/L/s,Kcat为23.65/s;酶解最慢的反应所对应的Km为29.94μmol/L,Vmax为11.35μmol/L/s,Kcat为20.63/s。研究结果对于填补赛多孢菌毒力因子研究的空白、针对毒力因子开发新型的抗真菌药物和治疗方法都具有重要意义。 相似文献
86.
《Animal : an international journal of animal bioscience》2020,14(3):491-498
Grape seed procyanidins (GSPs), widely known for their beneficial health properties, fail to bring about the expected improvement in piglets’ growth performance. The effects of dietary supplementation with GSPs on nutrient utilisation may be a critical influencing factor. Hence, the purpose of this study was to investigate the effects of dietary supplementation with GSPs on nutrient utilisation and gut function in weaned piglets. One hundred and twenty crossbred piglets were allocated randomly to four treatment groups, with three replicate pens per treatment and 10 piglets per pen. Each group was given one of the four dietary treatments: the basal diet (control group) or the basal diet with the addition of 50-, 100- or 150-mg/kg GSPs. The trial lasted 28 days. Faeces were collected from d 12 to 14 and from d 26 to 28 for measuring the coefficient of total tract apparent digestibility (CTTAD) of the nutrients. Blood samples were collected on d 14 and 28 for detecting the blood biochemical parameters. Two piglets per pen were slaughtered to collect the pancreas and intestinal digesta for evaluating the digestive enzyme activity and the coefficient of ileal apparent digestibility (CIAD) of the nutrients. On d 14 and 28, supplementation with 150-mg/kg GSPs significantly decreased the CTTAD of DM and CP in piglets. On d 14, GSPs supplementation at a concentration of 150 mg/kg led to a remarkable decrease in the CIAD of CP and gross energy (GE). On d 28, GSPs supplementation at a dose of 150 mg/kg generated a marked decline in the CIAD of DM, GE, CP and ether extract. Grape seed procyanidins supplementation at concentrations of 100 or 150 mg/kg inhibited the activities of lipase and amylase. In contrast, the jejunum mucosa maltase and sucrase activities increased due to the inclusion of GSPs at a concentration of 100 mg/kg in the piglet diet. Compared with the levels of the control group, the serum glucose and total protein levels were enhanced significantly by supplementation with GSPs at 100 mg/kg and reduced dramatically at 150 mg/kg. The serum diamine oxidase activity and endotoxin levels were decreased by GSPs supplementation in piglet diets. In conclusion, higher concentrations of GSPs in weaned piglet diets attenuated nutrient digestion and inhibited digestive enzyme activity; however, suitable concentrations of GSPs could promote brush-border enzyme activity, enhance serum glucose and total protein concentrations and decrease epithelial permeability. 相似文献
87.
《Animal : an international journal of animal bioscience》2020,14(9):1793-1801
In the mink industry, feed costs are the largest variable expense and breeding for feed efficient animals is warranted. Implementation of selection for feed efficiency must consider the relationships between feed efficiency and the current selection traits BW and litter size. Often, feed intake (FI) is recorded on a cage with a male and a female and there is sexual dimorphism that needs to be accounted for. Study aims were to (1) model group recorded FI accounting for sexual dimorphism, (2) derive genetic residual feed intake (RFI) as a measure of feed efficiency, (3) examine the relationship between feed efficiency and BW in males (BWM) and females (BWF) and litter size at day 21 after whelping (LS21) in Danish brown mink and (4) investigate direct and correlated response to selection on each trait of interest. Feed intake records from 9574 cages, BW records on 16 782 males and 16 875 females and LS21 records on 6446 yearling females were used for analysis. Genetic parameters for FI, BWM, BWF and LS21 were obtained using a multivariate animal model, yielding sex-specific additive genetic variances for FI and BW to account for sexual dimorphism. The analysis was performed in a Bayesian setting using Gibbs sampling, and genetic RFI was obtained from the conditional distribution of FI given BW using genetic regression coefficients. Responses to single trait selection were defined as the posterior distribution of genetic superiority of the top 10% of animals after conditioning on the genetic trends. The heritabilities ranged from 0.13 for RFI in females and LS21 to 0.59 for BWF. Genetic correlations between BW in both sexes and LS21 and FI in both sexes were unfavorable, and single trait selection on BW in either sex showed increased FI in both sexes and reduced litter size. Due to the definition of RFI and high genetic correlation between BWM and BWF, selection on RFI did not significantly alter BW. In addition, selection on RFI in either sex did not affect LS21. Genetic correlation between sexes for FI and BW was high but significantly lower than unity. The high correlations across sex allowed for selection on standardized averages of animals’ breeding values (BVs) for RFI, FI and BW, which yielded selection responses approximately equal to the responses obtained using the sex-specific BVs. The results illustrate the possibility of selecting against RFI in mink with no negative effects on BW and litter size. 相似文献
88.
Neda Milinkovi? Marija Sari? Sne?ana Jovi?i? Du?ko Mirkovi? Vi?nja Le?ai? Svetlana Ignjatovi? 《Journal of Medical Biochemistry》2020,39(3):309
BackgroundSome observational studies indicate an association of 25-hydroxy vitamin D (25(OH)D) insufficiency and atherogenic cholesterol concentrations. The aim of this study was to investigate relationship between 25(OH)D concentrations and lipid parameters in end stage renal disease (ESRD) patients, separately for predialysis, hemodialysis and peritoneal dialysis patients.MethodsWe have adjusted 25(OH)D concentrations for seasonal variability with cosinor analysis, and performed all further analysis using these corrected 25(OH)D concentrations. Concentrations of 25(OH)D and the lipid parameters were determined in 214 ESRD patients and 50 control group participants. The analysis included the measurement of 25(OH)D by HPLC, apolipoprotein (Apo) AI, ApoB and Lp(a) by nephelometry, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) by spectrophotometry and manually calculated ApoB/ApoAI and LDL-C/HDL-C ratio.ResultsESRD patients with adjusted 25(OH)D concentrations of 50 nmol/L had significantly higher TC (P = 0.005) and ApoAI (P = 0.049). Significantly higher HDLC (P = 0.011) and ApoAI (P = 0.020) were found in hemodialysis patients with the 25(OH)D concentrations of 50 nmol/L. The other analyzed lipid parameters differed significantly between predialysis, hemodialysis and peritoneal dialysis patients with 25(OH)D concentrations of < 50 nmol/L.ConclusionsOur study indicate the significant relationship between 25(OH)D repletion and optimal concentrations of lipid parameters in ESRD patients. Further research is necessary to explain whether joint evaluation of vitamin D status and lipid abnormalities could improve cardiovascular outcome in ESRD patients. 相似文献
89.
Alexander N. Prutkov Andrey V. Matveev Lyubov E. Grebenkina Mikhail G. Akimov Yulia V. Berezovskaya 《Nucleosides, nucleotides & nucleic acids》2020,39(7):943-963
AbstractSome 5-substituted ribavirin analogues have a high antiviral and anticancer activity, but their mechanisms of action are obviously not the same as their parent compound. The SAR studies performed on 3 (5)-substituted 1,2,4-triazole nucleosides have shown a high dependency between the structure of the 3 (5)-substituent and the level of antiviral/anticancer activity. The most active substances of the row contain coplanar with the 1,2,4-triazole ring aromatic substituent which is connected by a rigid ethynyl bond. However, the compounds with the trans-vinyl linker also had antiviral activity. We decided to study the antitumor activity of ribavirin analogues with alkyl/aryl vinyl substituents in the 5th position of the 1,2,4-triazole ring. Protected nucleoside analogues with various 5-alkylvinyl substituents were obtained by Horner-Wadsworth-Emmons reaction from the common precursor and converted to the nucleosides. Arylvinyl nucleosides were synthesised according the reported procedures. All compounds did not show significant antiproliferative activity on several tumour cell lines. Coplanar aromatic motif in the 5-substituent for the anticancer activity manifestation was confirmed. 相似文献
90.
以黄土高原10个典型样点的20年刺槐人工林为研究对象,测定了样地中刺槐叶片碳(C)、氮(N)、磷(P)含量,以及0-10 cm和10-20 cm土层土壤的主要理化指标,探讨了黄土高原刺槐叶片-土壤生态化学计量特征参数随水分梯度的变化规律。研究结果发现:①随着降水量增加,刺槐叶C、N含量呈增加趋势,叶片P含量无一致性规律。② 0-10 cm土层中土壤SOC、TN、TP、铵态氮含量以及C ∶ P和N ∶ P均随降雨量增加呈逐渐增加趋势,而C ∶ N比变化不明显。③刺槐叶片C、N、P及其化学计量比与土壤化学计量比相关性较弱,但叶片N、P与土壤铵态氮、速效磷等速效养分含量呈显著正相关(P<0.05)。本研究叶片N ∶ P>16,说明黄土高原刺槐生长主要受P元素限制,且随着降水的增加,土壤P养分的限制加强。 相似文献