Lactate Production from Glucose and Response to Insulin in Perifused Adipocytes from Mesenteric and Epididymal Regions of Lean and Obese Rats

Lactate, an important metabolic substrate for peripheral tissues and the liver, is released in significant amounts from adipose tissue. Using a perifusion system, we measured lactate production from glucose and response to insulin in isolated mesenteric and epididymal adipocytes removed from fed or fasted male Wistar rats at two stages of growth and development: (a) lean rats (7 weeks to 9 weeks old, weighing ～250 g), and (b) fatter rats (6 months to 8 months old, weighing ～550 g). The results show that lactate production in perifused adipocytes is regulated by the prior nutritional state of the animals, by the adipose tissue region, and by the presence of insulin in the perifusate. In fat cells from lean rats, basal lactate production was significantly higher (p<0.05) in mesenteric cells when compared with epididymal cells, both in the fed state (7.8 nmol/10⁷ fat cells per minute vs. 2.9 nmol/10⁷ fat cells per minute) and after 2 days of fasting (13.6 nmol vs. 3.5 nmol). When the response to 1 mU/mL insulin was studied, however, the relative increase in lactate production produced by insulin was greater in the epididymal cells than in the mesenteric cells, in both the fed (194% vs. 91% over basal, respectively) and fasted (360% vs. 55% over basal, p<0.05) state. When larger epididymal adipocytes from fatter rats were compared with an equal number of smaller epididymal cells from leaner rats, the larger cells produced 4.99 nmol of lactate/10⁷ fat cells per minute, whereas the smaller cells produced 2.93 nmol (p=0.08). Large fat cells showed a small and nonsignificant response to insulin in either type of cell (epididymal vs. mesenteric) or nutritional state (fed vs. fasted). This study indicates that distinct regional differences exist in lactate production and response to insulin. Mesenteric adipose tissue, which drains directly into the portal vein and provides substrates to the liver, may be an important source of lactate for the hepatic processes of gluconeogenesis and glycogenesis.     

The influence of predation risk on diet selectivity: A theoretical analysis

Studies that have examined the effect of experimental increases in predation risk on diet selectivity have shown both decreased and increased diet selectivity. A possible explanation for these disparate results emerges from an examination of the prey sets used in these studies, which differed in the relationship between the values of risk components associated with the capture of different prey types (‘danger’) and their profitabilities. When less profitable prey were more dangerous, selectivity increased with predation risk. When prey were equally dangerous, selectivity did not change. Finally, when the more profitable prey were also more dangerous, selectivity decreased with risk. Here, we examine theoretically the influence of a forager's estimate of the probability that a predator is present (φ) on the selection of diets from prey sets with varying danger–profitability relationships. A dynamic programming model is used to determine the maximum attack time (or distance) for each of two types of prey, differing in their energetic content, for a range of forager energy state and φ levels. The diets which would result if foragers attacked prey according to the rules provided by the dynamic model are then determined. The model results indicate that the prey danger–profitability relationship determines the diet selectivity response to φ, confirming that variation in this relationship could be responsible for the range of experimental results. This revised version was published online in July 2006 with corrections to the Cover Date.     

基于多判据决策的水体营养状态评价

为了准确地评价水生态系统营养状态和综合决策,通过最大熵原理耦合模糊性与随机性,建立了最大熵模糊评价模型(FAME);利用逼近理想解排序法(TOPSIS),以待决策水体样本的实测值为理想解,以评价结果中与实测值相差最大的为负理想解,建立了多判据决策模型(MCDM).经12个湖泊实测数据验证,最大熵模糊评价与随机评价、模糊评价和灰色评价的结果较为一致,但提高了评价水体营养状态问题各层次的分辨力.多判据决策模型可解决多种方法评价结果不相容问题,使评价结果更接近水体实际情况.FAME和MCDM适用于各种水质的综合评价及决策.     

术前预后营养指数和血清转铁蛋白与老年髋部骨折患者术后切口愈合的关系及其预测价值分析

摘要 目的：研究术前预后营养指数（PNI）和血清转铁蛋白（TRF）与老年髋部骨折（HF）患者术后切口愈合不良（PWH）的关系及其预测价值。方法：选取2020年1月～2022年3月南京市中医院收治的252例接受手术治疗老年HF患者,根据术后切口愈合情况分为PWH组（n=27）和非PWH组（n=225）。收集患者基础资料、术前PNI和血清TRF水平。采用多因素Logistic回归分析老年HF患者术后PWH的影响因素,受试者工作特征（ROC）曲线分析PNI和血清TRF水平对老年HF患者术后PWH的预测价值。结果：252例老年HF患者术后出现27例PWH,其中24例切口长时间不愈合,3例切口裂开。与非PWH组比较,PWH组体质量指数（BMI）和白蛋白、淋巴细胞计数（LC）、PNI、血清TRF水平更低,糖尿病比例和术中出血量更高（P＜0.05）。多因素Logistic回归分析显示,BMI≥18.5 kg/m²（OR=0.648,95％CI：0.457～0.919）、PNI（OR=0.954,95％CI：0.932～0.976）、血清TRF（OR=0.484,95％CI：0.307～0.761）升高是老年HF患者术后PWH的保护因素,糖尿病（OR=2.651,95％CI：1.182～5.948）、术中出血量增加（OR=1.013,95％CI：1.005～1.021）是危险因素（P＜0.05）。ROC曲线分析显示,PNI和血清TRF水平单独与联合预测老年HF患者术后PWH的曲线下面积（AUC）分别为0.808、0.770、0.871,灵敏度分别为70.37％、55.56％、92.59％,特异度分别为80.65％、85.81％、70.32％。二者联合预测老年HF患者术后PWH的AUC大于二者单独预测（P＜0.05）。结论：术前PNI和血清TRF水平降低是老年HF患者术后PWH的危险因素,二者联合对老年HF患者术后PWH的预测价值较高。     

泰山沙参属植物资源调查与营养成分分析

目的:了解泰山沙参属植物资源现状,测定其根中脂肪、蛋白质及多糖的含量,为合理开发利用泰山沙参属植物资源提供依据。方法:采用野外实地调查法进行资源考察;分别用索氏提取法、考马斯亮蓝法和苯酚-硫酸法测定脂肪、蛋白质和多糖的含量。结果:采集的100余份标本,经鉴定为沙参属植物狭叶沙参[Adenophora gmeli-nii(Spreng)Fisch.]、石沙参(Adenophora polyantha Nakai)、杏叶沙参(Adenophora stricta Mig.)及细叶沙参(Adeno-phora paniculata Nannf.)。泰山沙参属植物狭叶沙参、石沙参、杏叶沙参和细叶沙参脂肪含量分别为2.14%～7.34%,4.27%～7.72%1,.54%～2.51%和4.98%。蛋白质含量分别为0.60～2.10 mg/g0,.80～1.89 mg/g,0.83～0.89 mg/g和1.05 mg/g,多糖含量分别为20.58%～63.21%2,7.74%～65.14%,43.14%～48.47%和45.60%。结论:泰山野生沙参属植物资源丰富,品种多、分布广、蕴藏量大,多糖含量较高,具有较大的开发前景。     

菊黄东方鲀、暗纹东方鲀及其杂交F1代肌肉营养成分的比较分析

为了了解菊黄东方鲀(Takifugu flavidus)、暗纹东方鲀(T.obscurus)及其杂交F1代的肌肉营养特征,利用生物化学方法,从每类实验样本中取9尾对其肌肉中的粗蛋白、粗脂肪、水分、粗灰分和氨基酸成分进行了测定和分析。结果显示:(1)杂交F1代在生长方面具有明显的杂交优势,与亲本之间存在着显著差异(P0.05),杂交F1代的体重为其亲本的1.48~1.77倍;(2)杂交F1代肌肉水分含量与其母本含量相近,但粗脂肪含量均较亲本少(P0.05),粗蛋白含量则与亲本差异不显著(P0.05);(3)除色氨酸和胱氨酸外,16种氨基酸均在肌肉样本中被检测到,除甲硫氨酸外,其余15种氨基酸间含量均存在着显著性差异(P0.05)。菊黄东方鲀(♀)×暗纹东方鲀(♂)杂交F1代的总氨基酸含量最高,而暗纹东方鲀(♀)×菊黄东方鲀(♂)F1代总氨基酸含量则介于两亲本之间。对其必需氨基酸总量进行分析发现,菊黄东方鲀与其正反杂交F1代之间均存在显著性差异(P0.05),而暗纹东方鲀与其正反杂交F1代之间差异不显著(P0.05);(4)肌肉营养品质评价结果表明,菊黄东方鲀(♀)×暗纹东方鲀(♂)杂交F1代的鲜味氨基酸含量为26.68%,明显高于双亲样本(菊黄东方鲀22.28%、暗纹东方鲀25.20%),而暗纹东方鲀(♀)×菊黄东方鲀(♂)F1代的鲜味氨基酸总量(23.30%)较其父本偏高,但低于其母本。研究结果表明,杂交东方鲀的肌肉营养综合了双亲的优良特性,特别是是菊黄东方鲀(♀)×暗纹东方鲀(♂)杂交F1代,拥有最高的鲜味氨基酸含量,具有推广价值。     

Improving the mineral reserves and protein quality of maize (Zea mays L.) kernels using unique genes

The effects of the maize genes, o ₂ and Mal, on the concentrations of mineral nutrient cations and amino acid levels in mature maize (Zea mays L) kernels of various inbred lines were studied. Previously, the o ₂ gene has been used to improve the protein quality and increase the mineral nutrient content of kernels from some inbred lines. Genotypes possessing the Mal (multiple aleurone layer) gene, contain more than one row of aleurone cells in their kernels and this gene enhances the effect of the o ₂gene on improving kernel protein quality. Incorporating these genes into the maize genome increased accumulation of several mineral nutrients (including Ca, Mg, Zn, Fe, Mn, Zn and Cu) in some of the experimental lines studied. The physiological basis for this increase of mineral nutrients in the kernels is discussed. The effect of the Mal gene on the kernel amino acid composition and protein quality was also examined. Possibly, these genes could be used in combination in breeding programs to improve kernel quality and nutritional value of maize.     

五种食用菌氨基酸含量的测定及营养评价

研究测定了五种食用菌中氨基酸的含量,并利用五种非生物学指标对蛋白质的营养价值进行评价。五种食用菌氨基酸种类齐全,必需氨基酸占氨基酸总量的百分比分别达到45.94%、37.62%、42.45%、41.54%、35.98%。茶树菇和姬松茸的限制性氨基酸为半胱氨酸和甲硫氨酸,鸡腿菇、香菇和黑木耳的限制性氨基酸是缬氨酸。不同的评价指标对蛋白质进行营养评价,评价结果会有所差异。     

The Locally Optimal Method of Cyclic Alignment to Reveal Latent Periodicities in Genetic Texts: the NAD-binding Protein Sites

A program package has been developed to search for hidden tandem repeats of any specified type in the protein sequence databases. The applied algorithm of the locally optimal cyclic alignment is able to find subsequences possessing a certain profile-based periodicity type when no appreciable homology between periods is observed, as well as in the presence of arbitrary insertions/deletions. The profile can be adjusted to search for the periodicity types structurally and functionally important. The Swiss-Prot database has been analyzed to reveal the periodicities undetectable earlier that are caused by the secondary and super-secondary structure regularities of the NAD-binding sites. In particular, a significant periodicity of 24 aa was found to be characteristic of the absolute majority of domains possessing the Rossman (or Rossman-like) fold and displaying apparent regularity in their secondary structures, not being obvious at the primary structure level.