姬松茸深层发酵培养基的优化

通过姬松茸碳氮源筛选的单因素实验 ,确定玉米粉、蔗糖为碳源 ,豆粕粉、麸皮汁为氮源 ;在此基础上 ,进行了碳氮源质量浓度及比例实验、摇瓶发酵正交实验 ,优化培养基配方 ,确定姬松茸摇瓶发酵培养基的最佳配方为 :玉米粉 1 .5g/dL ,蔗糖 0 .5 g/dL ,麸皮汁 0 .5 g/dL ,豆饼粉 2 .0 g/dL .     

姬松茸多糖提取条件及其沉淀特性

研究了不同的提取温度、提取时间和加水比 ,对姬松茸液体发酵菌丝体和固体栽培子实体粗多糖提取得率的影响 .采用二元二次回归的分析方法得姬松茸菌丝体和子实体的最佳提取条件为 :菌丝体为 10倍加水量于 90℃提取 3.3h ;子实体为 10倍加水量于 90℃提取 3.4h .提取率可以分别达到 1.376 %和 1.6 40 % .在此基础上 ,比较了乙醇质量分数和提取液 pH对姬松茸子实体和菌丝体多糖沉淀特性的影响 .     

富锌姬松茸胞内多糖的分离及体内抑制小鼠肝癌的研究

研究了经DEAE-纤维素离子交换柱分离的富锌液态发酵姬松茸胞内多糖组分对小鼠肝癌实体型Heps的体内抑制效果,同时考察了柱层析过后各组分中锌元素的分布情况及给药后小鼠血清锌的变化情况。分离所得组分MP-2在5 mg/(kg.d)剂量下抑瘤率为59.5%(p<0.001),MP-3在10 mg/(kg.d)剂量下抑瘤率为68.1%(p<0.001),两样品在10 mg/(kg.d)剂量下均能使小鼠脾指数显著提高。组分MP-2含锌率3.38‰、MP-3含锌率2.46‰,远高于组分MP-1的含锌率0.12‰;注射样品MP-2、MP-3的实验组小鼠血清锌浓度皆显著高于不给予富锌样品的阴性对照组(p<0.05)。     

高强度产甘油假丝酵母突变株的选育及其发酵性状

以一株产甘油假丝酵母为出发菌株 ,采用化学诱变 ,通过玉米浆和外加无机磷组成的磷质量浓度为 3 40mg/L的磷源选择培养基 ,得到了一株发酵时间较原菌株缩短了 8h左右 ,产甘油能力 (甘油产量约为 1 40 g/L ,甘油转化率为 5 6% )和原菌株相似的突变株 ,并研究了突变株的发酵性状 .     

EGSB反应器处理高浓硫酸盐废水

研究在负荷为20 kg COD/(m3.d)正常运行的EGSB(Expanded Granular Sludge Bed)反应器中,处理高浓硫酸盐废水。经过一个月左右的驯化,在进水COD为4 000 mg/L的条件下,进水SO42-质量浓度可提升至约1 800 mg/L,获得了9 kg SO42-/(m3.d)的运行能力。较高的有机负荷使得产气量较大随之带来明显的气提效应,再加上较高的上升流速所产生的良好的气固分离效果,使得气相中的硫元素含量较高,达到了质量分数43.8%。硫酸盐还原菌所能达到的最大电子流比重为31.4%,对应的最低COD/SO42-值约为2.0。EGSB反应器内溶解性硫化物与相应的自由硫化氢质量浓度为255 mg/L和102 mg/L,未对SRB与产甲烷菌产生任何毒性。     

ERK-MAPK信号转导通路在胃泌素促进人结直肠癌细胞增殖中的作用及其机制

目的 探讨细胞外信号调节蛋白激酶(ERK)-丝裂素活化蛋白激酶(MAPK)信号转导通路在胃泌素促进人结直肠癌细胞株HT-29增殖与凋亡中的作用及其机制.方法 体外培养结直肠癌HT-29细胞株,将细胞分为对照组、胃泌素组、丙谷胺组和胃泌素+丙谷胺组,胃泌素组设6.25、12.50、25.00、50.00、100.00 mg/L 5个浓度梯度,丙谷胺组设8.00、16.00、32.00、64.00、128.00 mg/L 5个浓度梯度,并设胃泌素(25.00 mg/L)+丙谷胺组(8.00、16.00、32.00、64.00、128.00 mg/L)浓度梯度.对照组不加药,其余各组加不同浓度的药物处理.运用MTT法观察细胞增殖活力改变情况,确立5-肽胃泌素和丙谷胺处理HT-29细胞的最佳浓度;流式细胞仪检测各组细胞增殖指数及凋亡率的变化;RT-PCR检测结直肠癌HT-29细胞株胃泌素/胆囊收缩素B受体(CCK-BR)mRNA表达情况以及各组细胞ERK1/2、K-rasmRNA表达水平的变化;Western blot检测ERK1/2和K-ras蛋白表达及其磷酸化水平.采用方差分析和SNK-q检验进行统计学分析.结果 胃泌素浓度在6.25～ 100.00 mg/L能促进结直肠癌HT-29细胞的增殖,且当浓度达25.00 mg/L时为最佳浓度(F=31.36,P＜0.05);单独丙谷胺对结直肠癌HT-29细胞增殖无明显影响,但丙谷胺浓度在8.00 ～ 128.00 mg/L能明显拮抗胃泌素促进HT-29细胞的增殖作用,其最佳浓度为32.00 mg/L(F =24.31,P＜0.05).胃泌素(25.00 mg/L)组细胞增殖指数为37.5％±5.2％,显著高于对照组的27.7％±5.0％和胃泌素(25.00 mg/L)+丙谷胺(32.00 mg/L)组的27.3％±5.8％(q=4.56,4.75,P＜0.05);胃泌素(25.00 mg/L)组细胞凋亡率为1.9％±0.4％,低于对照组的2.5％±0.4％和胃泌素(25.00 mg/L)+丙谷胺(32.00 mg/L)组的2.4％±0.3％(q＝4.23,4.06,P＜0.05).HT-29细胞中存在明显的CCK-BR mRNA表达.胃泌素(25.00 mg/L)组磷酸化ERK1/2、磷酸化K-ras蛋白相对表达量分别为0.43％±0.04％和0.45％±0.06％,高于对照组的0.32％±0.02％和0.31％±0.05％(q =7.78,4.95,P＜0.05),也高于胃泌素(25.00 mg/L)+丙谷胺(32.00 mg/L)组的0.36％±0.01％和0.35％±0.04％(q=5.72,4.08,P＜0.05);但对照组、胃泌素(25.00 mg/L)组、丙谷胺(32.00 mg/L)组、胃泌素(25.00 mg/L)+丙谷胺(32.00 mg/L)组间ERK1/2 mRNA和蛋白表达水平以及K-ras mRNA和蛋白表达水平比较,差异均无统计学意义(F=0.52,0.72,0.78,0.28,P＞0.05).结论 胃泌素可以促进结直肠癌细胞株HT-29的增殖,抑制细胞凋亡,其作用可能是通过ERK-MAPK信号通路中Ras→ Raf→ MEK1/2→ERK1/2途径上调ERK和K-ras的磷酸化水平来实现的,但能够被其受体拮抗剂丙谷胺抑制.     

好氧颗粒污泥同步硝化反硝化脱氮过程中N2O的产生

对同步脱氮过程中影响N2O产生的条件进行了研究.结果表明,由于受反硝化反应影响,COD/NH+4-N比值为2,3时产生较多的N2O,分别为15 mg/L和25 mg/L;而比值为4,5时N2O生成量较少.同样,较高的溶氧质量浓度(3,4 mg/L)减小了颗粒污泥内部的反硝化区域,反应产生较多的N2O,控制DO质量浓度在1～2 mg/L,有利于减少N2O的排放.脱氮过程中添加NO-2-N和NO-3-N,反应产生大量的N2O,最多可以达到75 mg/L. 实验发现,NO-2-N较NO-3-N更易形成N2O.     

低聚壳聚糖Zn（Ⅱ）配合物清除DPPH活性的研究

控制反应物低聚壳聚糖和氯化锌的比例,合成了两种金属含量不同的低聚壳聚糖锌配合物,用红外光谱对产物结构进行表征,原子吸收光谱证实两种配合物中的锌质量分数分别为5.04%和8.68%.考察了其对DPPH的清除活性,结果表明:两种配合物对DPPH有明显的清除效果,锌质量分数为5.04%和8.68%的低聚壳聚糖锌配合物对DPPH的半抑制浓度IC50分别为1.50 mg/mL和1.76 mg/mL,但均大于低聚壳聚糖对DPPH的半抑制浓度IC500.42 mg/mL,这可能是因为金属离子的引进,使部分活性氨基和羟基的数目减少所致.     

离子对啤酒酵母代谢产酸的影响

在离子型培养基中分别添加6.804,13.610,27.216 g/L 的KH2PO4以及66.39,138.75, 277.4 mg /L 的CaCl2,对通风发酵过程中的不同K^＋、Ca^2＋浓度影响啤酒酵母代谢产6种有机酸含量的动态变化进行了跟踪检测.研究结果表明,K^＋、Ca^2＋可能通过作用于酵母细胞膜上的膜蛋白或调控生理代谢网络中代谢流相关的酶,从而使不同的K^＋、Ca^2＋浓度影响啤酒酵母响应产酸的峰值和峰值响应时间;在通风发酵过程中,啤酒酵母代谢产乳酸较多（多达8.3 mg/mL）,产琥珀酸较少（不超过250 μg/mL）;发酵终点时,随K^＋、Ca^2＋浓度增大,啤酒酵母代谢产酒石酸和琥珀酸等含量减少.     

舒芬太尼对老年患者诱导期丙泊酚抑制气管插管反应半数有效血浆浓度的影响

目的 探讨不同靶浓度的舒芬太尼复合丙泊酚靶控输注(targeted-controlled infusion,TCI)抑制气管插管反应的丙泊酚半数有效血浆浓度(the median effective plasma concentration,Cp50).方法 研究对象为94例择期全麻拟行气管插管手术患者,ASA Ⅰ～Ⅲ级,年龄在60岁～79岁.根据年龄段和舒芬太尼靶浓度的不同按随机数字表法分为4组,A组为60岁～69岁、0.2 μg/L;B组为60岁～69岁、0.3 μg/L;C组为70岁～79岁、0.2 μg/L;D组为70岁～79岁、0.3 μg/L.试验以效应室浓度TCI舒芬太尼,待舒芬太尼血浆浓度与效应室浓度平衡后,以血浆靶浓度TCI丙泊酚,意识消失后给予0.2 mg/kg的顺阿曲库铵,待丙泊酚的血浆浓度和效应室浓度平衡且静注顺阿曲库铵达3 min后行气管插管.丙泊酚的血浆靶浓度按序贯法确定.结果 A组患者有效抑制气管插管反应的丙泊酚的Cp50为3.60 mg/L,95％可信区间(confidence interval,CI)为3.44 mgl～3.76 mg/L;B组患者Cp50为2.03 mg/L,95％CI为1.88 mg/L～2.20 mg/L;C组患者Cp50为2.70 mg/L,95％CI为2.56 mg/L～2.84 mg/L;D组患者Cp50为1.97 mg/L,95％CI为1.81 mg/L～2.12 mg/L.结论 随着舒芬太尼的效应室靶浓度的增加以及年龄的增加,丙泊酚的Cp50明显降低.     

巴西蘑菇多糖的免疫调节作用

对巴西蘑菇发酵液提取的胞外多糖和菌丝体多糖的免疫功能进行了研究 .结果表明 ,巴西蘑菇多糖可促进免疫器官的增殖 ,延缓其衰退 ,促进迟发型超敏反应 (DTH)的发生 ,能增强巨噬细胞的吞噬功能 ,但对体液免疫的作用不明显 .巴西蘑菇多糖主要通过增强非特异性免疫和促进细胞免疫来发挥作用 .     

Medical mushrooms used for biochemical failure after radical treatment for prostate cancer: An open‐label study

Objective: The aim of this study was to assess the efficacy and safety of two different types of medical mushrooms in patients with prostate cancer in Japan. Methods: Patients with biochemical failure after radical treatment for non‐metastasized prostate cancer were enrolled in this open‐label study. For 6 months they ingested one of the two following supplements: Senseiro, containing extracts from the Agaricus blazei Murill mushroom; and Rokkaku Reishi, containing the Ganoderma lucidum mushroom. Levels of serum prostate‐specific antigen (PSA) level and PSA doubling time were examined before and after study entry to assess the impact of these supplements on disease progression. The primary end‐point of this study was partial response rate (50% or more decrease of serum PSA). Hormonal status, represented by serum testosterone levels, and toxicity were also assessed. Results: A total of 51 patients were enrolled following radical prostatectomy. Forty‐seven completed the protocol and could be assessed. Thirty‐two patients received Senseiro and the remaining 15 received Rokkaku Reishi. No partial response in terms of PSA was observed. Alteration of PSA doubling time did not correlate with that of serum testosterone levels. Serious adverse effects were not observed. Conclusions: No significant anticancer effects were observed with the intake of these two medical mushrooms.     

Influence of maternal dietary Zn intake on expression of diabetes-induced teratogenicity in rats

Diabetic rat pregnancies are characterized by altered maternal and fetal Zn metabolism and a higher frequency of fetal malformations. In this study, the effect of varying maternal dietary Zn on pregnancy and fetal outcome and on maternal and fetal trace element status were investigated. Starting on day 0 of gestation, streptozocin-induced diabetic and nondiabetic control rats were fed a low-Zn diet (4.5 micrograms/g diet), an adequate-Zn diet (24.5 micrograms/g diet), or a high-Zn diet (500 micrograms/g diet) throughout gestation. Fetuses were taken by cesarean section on gestation day 20. Fetuses from diabetic dams were smaller, weighed less, and had less calcified skeletons and more malformations than fetuses from control dams. In the controls, maternal dietary Zn had a minor effect on fetal malformation frequency. In contrast, in the diabetic animals, the low-Zn diet had a strong teratogenic effect. In diabetic dams, the adequate- and high-Zn diets improved fetal length and weight more than it did in fetuses from nondiabetic dams. However, supplemental dietary Zn during diabetic pregnancy did not further improve malformation frequencies. Liver and kidney Zn, Cu, and metallothionein concentrations were higher in diabetic dams than in control dams. In contrast, liver Zn, Cu, and metallothionein concentrations in fetuses of diabetic dams were lower than in fetuses from control dams, regardless of maternal dietary Zn intake. These results show that diabetes during pregnancy can amplify the teratogenic effects of a mild maternal Zn deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)     

Endocrine,Metabolic and Clinical Effects of Intravenous Endotoxin Injection after Pre‐Treatment with Meloxicam in Heifers

Meloxicam (M), a non‐steroid anti‐inflammatory drug for use in animals, reduces prostaglandin (PG) synthesis by inhibiting cyclooxygenases‐1 and ‐2. The aim of this study was to evaluate M's capability to prevent the inflammatory response elicited by endotoxin (ET). Furthermore, we wanted to evaluate a possible effect of M on Δ¹³‐reductase and 15‐hydroxy prostanoate dehydrogenase, enzymes responsible for the initial metabolism of PGF_2α. Four heifers acting as their own controls were used in the study. The heifers received an i.v. injection of either saline (S) or M (0.5 mg/kg) at 1.5 h before an i.v. injection of ET (50 ng/kg b.w. i.v.). The trial lasted 57 h after ET injection and blood samples were withdrawn for analyses of 15‐ketodihydro‐PGF_2α (PG metabolite), cortisol, white blood cells (WBC), Fe, Zn and Ca. Clinical examinations were performed throughout the trial. In the S + ET trial, ET injection elicited a rapid increase of the PG metabolite, a prolonged cortisol release and reduced levels of WBC, Fe, Zn and Ca. General appearance and body temperature were affected. In the M + ET trial the PG release was totally abolished, the cortisol release was reduced and the clinical effect was milder, also effects on Fe, Zn and Ca were milder in the M + ET trial, but M did not prevent the pyrogenic effect of ET. In the next two trials, we injected PGF_2α (500 ng/kg i.v.) with and without M pre‐treatment. After PGF_2α injection, plasma samples were collected for measurement of the PG metabolite. M had no effect on PGF_2α metabolism. In conclusion, M effectively suppresses several of the inflammatory reactions seen after ET injections and has no major influence on the PGF_2α metabolism.     

Edible mushroom (Agaricus bisporus) lectin inhibits human retinal pigment epithelial cell proliferation in vitro

The retinal pigment epithelium (RPE) plays a major role in the development of the anomalous retinal scarring response termed proliferative vitreoretinopathy. The present study was undertaken to investigate whether agaricus bisporus lectin inhibited human RPE proliferation in vitro. Fluorescein isothiocyanate-labeled agaricus bisporus lectin was used to study binding of lectin to cultured human RPE. The effect of a 24-hour exposure of agaricus bisporus lectin on RPE proliferation was measured using (methyl-3H)-thymidine incorporation into DNA. Toxicity studies were assessed using morphologic evaluation, trypan blue exclusion, and a cell viability assay. Agaricus bisporus lectin bound to RPE cells and was inhibited by preincubation of lectin with asialomucin. Agaricus bisporus lectin caused a dose-dependent inhibition of RPE proliferation (one-way ANOVA, F = 94.470, p < 0.001) that was partially reversible on removal of the lectin. Compared with controls, cells remained viable and no morphological changes or trypan blue staining was noted in RPE exposed to agaricus bisporus lectin. Human RPE binds agaricus bisporus lectin and inhibits proliferation without apparent cytotoxicity. It therefore merits consideration as a potential antiproliferative agent in the prevention and treatment of proliferative vitreoretinopathy and other nonocular anomalous wound healing processes.     

Effects of oral zinc administration on long‐term ipsilateral and contralateral testes damage after experimental testis ischaemia–reperfusion

The purpose of this study was to examine potential long‐term post‐torsion changes that can occur in the histopathology, biochemistry and spermatogenesis of both torsioned and nontorsioned opposite testes. The study also determines the effect of zinc (Zn) administration on the testicular torsion/detorsion (T/D) damage on both testes. Forty‐eight male rats, divided equally into eight groups: (SHAM), (SHAM+,Zn+), (T/D+, Zn? 1 month), (T/D+,Zn? 2 months), (T/D+,Zn? 3 months), (T/D+,Zn+ 1 months), (T/D+,Zn+ 2 months), (T/D+,Zn+ 3 months), have been used. Drug administration was carried out by adding 100 μg (0.016 ml/rat) Zn per rat to drinking water in related groups. Testicular damage decreased superoxide dismutase (SOD) and glutathione (GSH) and increased malondialdehyde (MDA) in the testis tissues of rats, while Zn administration increased SOD and GSH and decreased MDA in the testis tissues in comparison with the SHAM group. The beneficial effect of zinc sulphate was more evident on the nonrotated testis than the rotated testis. In the histopathological study, a significant decrease in torsion and detorsion injuries was observed in the treatment groups compared to the torsion and detorsion groups. We found a protective effect of zinc sulphate on oxidative stress as a result of T/D injuries in rats, especially for the nonrotated testis; results were supported histopathologically.     

The role of zinc in urinary stone disease

In recent years, the role of trace elements in lithogenesis has received steadily increasing attention. It is well documented that some trace elements can influence the morphology and speed of the crystallization process. Zinc has been found in significant amounts in calcium stones relative or organic stones (uric acid and cystine), probably substituting calcium in crystals because of their similarity in charge and size. High Zn levels are present in carbapatite of Randal’s plaques suggesting that zinc could promote calcium phosphate deposition in the medullar interstitium. Large-scale epidemiological studies have found an association of increased dietary zinc intake with increased risk of nephrolithiasis in adults but not in adolescents. Most studies examining urinary zinc levels in adults have reported increased urinary Zn excretion in stone formers. In an experimental model of organic crystal formation produced by silencing xanthine dehydrogenase in Drosophila fly, maneuvers that reduce Zn excretion have shown to reduce crystal formation in the lumen of the Malpighian tubules. This is curious because this is not a model of calcium stone formation. Finally, zinc supplementation has been associated with increased admissions for urinary lithiasis in men, but no change in calcium stone formation in children. Perhaps, some of these contradicting findings can be explained in part by the in vitro effect of zinc on the type and amount of calcium phosphate formed: At low concentrations, Zn inhibited the crystal growth of dicalcium phosphate dihydrate, octacalcium phosphate, and apatite, and at higher concentrations, it promoted the formation of amorphous calcium phosphate. Thus, further studies are needed to see whether manipulation of Zn metabolism can inhibit calcium stone formation.     

Insulinlike effects of zinc ion in vitro and in vivo. Preferential effects on desensitized adipocytes and induction of normoglycemia in streptozocin-induced rats.

The effects of Zn2+ in mimicking insulin in vivo and in vitro are further characterized. Like insulin, Zn2+ stimulated the conversion of [U-14C]-, [1-14C]-, and [6-14C]glucose to lipids in rat adipocytes. Maximum stimulation of lipogenesis was 55-80% of maximum insulin response after preincubation (30 min at 37 degrees C) of adipocytes with ZnCl2 (0.4 mM). Under these conditions, the half-maximum effect was achieved at 0.17 +/- 0.02 mM of ZnCl2. Similarly, an insulinlike effect of Zn2+ was observed on the oxidation of glucose by both pathways, glycolytic and hexose monophosphate shunt. In contrast, unlike insulin, Zn2+ did not inhibit lipolysis but rather exhibited a slight lipolytic activity. Also, the effect of Zn2+ on hexose influx did not exceed 14 +/- 3% that of insulin. The stimulatory effects of Zn2+ were not related to generation of H2O2. Catalase (100 micrograms/ml) did not inhibit Zn(2+)-stimulated glucose oxidation and its incorporation into lipids. Zn2+ had an additive effect on either insulin- or vanadate-stimulated conversion of [1-14C]glucose to fat, and together, the effect was approximately 140% of the maximum rate of lipogenesis. Chelation of intracellular Zn2+ by the cell-permeable chelator N,N,N',N'-tetrakis (2-pyridylmethyl)ethylenediamine did not significantly affect the ability of insulin to stimulate lipogenesis. Adipocytes derived from STZ rats were largely refractory to the modulating action of insulin. In contrast, the effect of Zn2+ on lipogenesis in these cells was more pronounced.(ABSTRACT TRUNCATED AT 250 WORDS)     

The role of trace minerals in the pathogenesis of postmenopausal osteoporosis and a new effect of calcitonin

The physiologic role of calcitonin in mineral and bone homeostasis is not very well understood. Very few longitudinal studies have reported the effects of calcitonin therapy on trace minerals in postmenopausal osteoporosis despite the documented involvement of trace minerals in normal skeletal metabolism. Several trace minerals, particularly magnesium (Mg) and zinc (Zn), essential for organic bone matrix synthesis have been known for at least three decades. The present study was designed to determine whether the mineral profile was different between 70 osteoporotic and 30 nonosteoporotic postmenopausal women and to evaluate the efficacy of calcitonin therapy for 6 months on these trace minerals in postmenopausal osteoporotic women. In our study, the serum values of Mg, copper (Cu), and Zn (P < 0.05) were significantly lower in the patient group than those in the control group. After 3 months of treatment, serum Cu, Zn, and Mg levels did not differ between the patients and controls, and this situation has continued after the end of 6 months of therapy. Serum Cu, Zn, and Mg levels increased consistently during the 6-month treatment period. The higher levels of serum Mg in the 3rd and 6th months of therapy were found to be statistically significant compared to those before treatment (P < 0.05). Serum Cu and Zn levels were found to be significantly higher at all measurements during the treatment period as well as at the end of therapy (P < 0.05). These results suggest that (1) calcitonin therapy regulates Mg, Cu, and Zn levels in postmenopausal osteoporosis; (2) when serum calcium and phosphorus were normal in postmenopausal osteoporosis, serum Mg, Cu, and Zn were more useful for evaluation; and (3) further studies are essential to evaluate the role of dietary composition on the manifestations of osteoporosis. Received: March 28, 2001 / Accepted: July 2, 2001