Study on the relationship between melatonin and hepatic encephalopathy

AIM:To explore the relationship between change of serum melatonin (MT) and pathogenesis of hepatic encephalopathy (HE). METHODS: Changes of MT level in sera of cirrhosic patients with HE and without HE were determined by ELISA, normal serum served as control. The change of serum MT level in exacerbation and remission in HE was also determined.RESULTS:MT level in patients with HE was higher than that withour HE (P＜0.01). MT levels of both groups were higher than that of normal group (P＜0.01). They were (308.53±59.07) ng/L, (139.85±34.59)ng/L,(77.73±28.41)ng/L, respectively. Serum MT level in exacerbation was higher than that in remission (P＜0.01), they were (301.52±66.42)ng/L and (147.81±23.31) ng/L, respectively. CONCLUSION: The elevation of MT content in sera may be closely related to the onset of hepatic coma.     

Effects of melatonin on gut motility

AIM: To investigate the influence of melatonin at different concentrations on the gut motility. METHODS: Male C57BL mice were used in the study. The mice were intraperitoneally injected with melatonin at doses of 1 mg/kg, 5 mg/kg, 50 mg/kg and 75 mg/kg. The colon bead expulsive time was measured at 15 min and 45 min after injection. The melatonin antagonist luzindole at a dose of 5 mg/kg was used before injection of 75mg/kg melatonin. The gut transit time was also recorded with oral Evens blue after injection of melatonin. RESULTS: Compared with control group, melatonin at the dose of 1 mg/kg at 15 min decreased the colon bead expulsive time. However, melatonin at high dose (75 mg/kg) prolonged the colon bead expulsive time compared with the control, which was effectively blocked by melatonin antagonist luzindole. Compared with control group, injection of melatonin at the dose of 5 mg/kg at 45 min decreased the colon bead expulsive time. However, melatonin at high dose (75 mg/kg) prolonged the colon bead expulsive time. No difference of colon bead expulsive time between using 1 mg/kg and 50 mg/kg melatonin was observed. In whole gut transit time test, after injection of melatonin at the doses of 1 mg/kg and 5 mg/kg, the time was decreased. The expulsive time of fecal pellet with Evens blue was shorten as compared with control group. However, the gut transit time was significantly prolonged after high dose of melatonin (75 mg/kg) was used. CONCLUSION: Low dose of melatonin increases while high dose decreases the gut motility. Melatonin antagonist luzindole effectively blocks the latter effect.     

促进观赏百合试管苗移栽成活的研究

对百合品种Connecticut King、Enchantment和Hinomoto在移植时期的营养液浓度和基质等方面进行了研究,结果表明,组培苗根长小于1cm时,是移植的最佳时期;在瓶苗移植过程中,不同时期应施用不同浓度的营养液。过渡培养15天后,即可将组培苗移植入土,最适宜的基质是1/3沙土 1/3草炭 1/3腐殖土。Hinomoto的组培苗较Enchant.ment和Connecticut King移植后容易成活,成活率达90％。     

外源褪黑素对桃生长及果实品质的影响

[目的]探讨外源褪黑素对桃生长和果实品质的影响.[方法]以早熟桃'早蜜'为试材,于果实膨大期对其叶片喷施不同浓度的褪黑素,测定了桃果实成熟期的新梢生长量、生理状况和果实品质指标.[结果]50?150 pmol?L-1的褪黑素处理能促进桃新梢的生长,增加其茎长和茎粗.150μmol L1褪黑素提高了桃叶片超氧化物歧化酶活...     

Protective effect of melatonin on mitochondria of ischemic-reperfusion injuried myocardium

AIM and METHODS: To study the protective effect of melatonin on mitochondria of rat myocardium on the ischemia-reperfusion model in vivo, and discuss its mechanism in terms of oxygen free radical, calcium overload and energy metabolism. RESULTS and CONCLUSION: 10 mg/kg melatonin administered 5 min before reperfusion, which obviously reduced the content of malondialdehyde of myocardial mitochondria, increased the content of glutathione, inhibited calcium overload, protected the integrality in mitochondrial structure, promoted the recovery of ability in ATP synthesis after reperfusion, maintained the energy metabolism of the myocardium.     

影响文心兰原球茎增殖生长诸因素的研究

以文心兰茎尖为外植体,诱导原球茎,并对影响原球茎增殖的几种因素进行了研究.结果表明:文心兰茎尖在1/2 MS+BA 2 mg/L+NAA 0.3 mg/L培养基上,离体培养大约30 d后产生原球茎;原球茎在1/2 MS+BA 1 mg/L+NAA 0.2 mg/L培养基上增殖速度最快,增殖系数可达2.6;与果糖和葡萄糖相比,蔗糖更有利于原球茎增殖;30 g/L的蔗糖对原球茎增殖生长有促进作用.     

胼胝兜兰的组培快繁技术研究

胼胝兜兰种子在自然条件下萌发困难,自然更新能力差。现采用人工授粉的种子,进行了非共生萌发研究。结果表明:270 d胚龄的种子萌发率高(95%);种子萌发最佳培养基为1/2RE+CM 100 mL/L+椰粉12 g/L+香蕉泥70 g/L+蔗糖20 g/L+琼脂粉5 g/L;壮苗培养基以MS+NAA 1.0 mg/L+BA 0.4 mg/L+椰粉12 g/L+香蕉70 g/L+蔗糖30 g/L+琼脂粉5 g/L为好,小苗用松树皮移栽效果好,移栽成活率95%以上。     

金针菇富碘栽培研究

本文对金针菇的富碘能力作了初步研究。金针菇液体培养菌丝体和栽培子实体均有较好的富碘性能。在添加Ｉ￣－浓度５０～１５００ｍｇ／Ｌ范围内，菌丝体富碘量为０．３６～２０．９ｍｇ／ｇ，碘富集率为１．８９～１０．９７％。喷洒施碘培养金针菇子实体的富碘效果较拌科施碘好。在５０～１０００ｍｇ／ｋｇ喷施Ｉ￣－范围内，子实体富碘量为０．０９４～０．３３ｍｇ／ｇ，碘富集率为２．１～２０．２％。碘对金针菇菌丝体和子实体的生长、生物量的合成有一定的抑制作用。     

Effects of melatonin on apoptosis of lymphocytes induced by ionizing radiation in mice

AIM: To explore the effect of melatonin (MLT) on the apoptosis of thymocytes and splenocytes in mice induced by ionizing radiation and its mechanism. METHODS: The percentages of apoptotic bodies and the DNA lytic rates of thymocytes and splenocytes in mice in vitro and in vivo were detected with flow cytometry and fluorospectrophotometry, respectively. RESULTS: The apoptosis of mouse thymocytes and splenocytes in vitro increased with significant dose-dependence in 0.5-6.0 Gy X-irradiation. When MLT of 2 mmol·L^-1 was added into thymocytes or splenocytes in vitro before irradiation with 0.5-6.0 Gy X-rays, the percentages of apoptotic bodies and the DNA lytic rates all decreased significantly as compared with those in the irradiation group. The percentages of apoptotic bodies in these two kinds of cells were 86.25% and 89.22% of those in the irradiation group, respectively, and the DNA lytic rates were 87.23% and 89.16%, respectively. When MLT was injected into intraperitonium in mice 60 min before whole-body irradiation with 2 Gy X-rays, the percentages of apoptotic bodies and the DNA lytic rates were significantly lower than those in the irradiation group, and near or lower than those in the sham-irradiation group. MLT of 0.1-2.5 mg/kg decreased the lymphocyte apoptosis, but without significant dose-dependence. CONCLUSION: The protective effects of MLT on mouse lymphocytes damaged by irradiation in vivo were obvious than those in vitro.     

Protection of melatonin on isoproterenol-induced hyperphosphorylation of tau and spatial memory impairment in rats

AIM: To study the in vivo effect of melatonin (MEL) on Alzheimer-like tau hyperphosphorylation and spatial memory retention impairment induced by isoproterenol (IP). METHODS: Simultaneous injection of 2 μL IP(10 mmol/L) or IP plus MEL(0.1 μg,1μg)into rat hippocampus bilaterally with stereotexin; The phosphorylation of tau was analyzed by immunohistochemistry and Western blot and the memory retention was tested by Morris Water Maze. RESULTS：Injection of IP induced hyperphosphorylation of tau at Tau-1 and PHF-1 epitopes and increased latency of rats to find the hidden platform in the Morris water maze. MEL significantly restored the IP-induced impairment in spatial memory（P＜0.05）and tau hyperphosphorylation determined by both immunocytochemistry and Western blot. CONCLUSION: MEL inhibits partially the IP-induced pathological processes in tau hyperphosphorylation and spatial memory impairment in rat brain.     

三种菇子实体不同部位组织分离培养菌丝生长研究

对三种菇（紫孢侧耳、香菇、金针菇）子实休不同部位组织分离，在三种培养基内菌丝生长情况进行了比较研究。结果表明：同一菇子实体的不同部位组织分离，在同一培养基内菌丝生长速度及长势存在着差异，而且不同培养基对三种菇子实体的不同部位组织分离培养菌丝的长速和长势也有显著的影响。     

香菇子实体释放孢子持续时间的初步研究

本文首次观察到，在月平均气温３．６～４．９℃的低温季节，生长在菇木上的香菇子实体释放担孢子的持续时间可达６１ｄ（天），采摘后的香菇子实体释放担孢子的持续时间可达２９ｄ。在相同气候条件下，香菇子实体释放担孢子的持续时间与菌盖直径成正比。     

外源褪黑素对盐胁迫下香椿种子萌发及幼苗生长的影响

为探究褪黑素对盐胁迫环境下香椿(Toona sinensis)种子萌发及幼苗生长的影响,以香椿为试材,采用清水处理为对照,利用NaCl模拟盐胁迫环境,分别用0、50、100、200、300μmol·L^-1的褪黑素处理香椿种子及幼苗,测定种子萌发后的各项生理指标。结果表明,盐胁迫处理显著抑制了香椿种子的发芽率、发芽势、发芽指数和根长,以及幼苗叶片的叶长、叶宽。与盐胁迫处理相比,100μmol·L^-1褪黑素预处理的香椿种子萌发和幼苗生长均得到显著改善,发芽率、发芽势、发芽指数分别显著提高了15.56%、18.89%、12.21%,叶长和叶宽提高了9.26、10.10 mm。盐胁迫导致香椿幼苗丙二醛含量和过氧化物酶活性显著高于对照,而超氧化物歧化酶活性显著低于对照。低浓度褪黑素预处理则显著降低了盐胁迫下丙二醛含量和过氧化物酶活性,提高了超氧化物酶活性。其中,提高香椿幼苗耐盐性的最适褪黑素浓度为100μmol·L^-1,与盐胁迫相比,丙二醛含量和过氧化物酶活性分别降低了6.19μmol·g^-1、6292.57 U·g^-1,超氧化物酶活性提高了22.16 U·g^-1。     

羊肚菌子实体培育研究初报

本文主要研究了２年羊肚菌菌株在不同栽培原料上和不同栽培条件下菌丝的生长情况、菌核的培养特征以及子实体的形成特性。结果表明,菌核是着羊肚菌子实体产生的重要标志和重要阶段;光照、温度和湿度是子实体形成的关键因子;北芪渣对菌核和子实体的形成有刺激作用;人工栽培适宜在杨树林地和苹果园进行;草木灰和杨树根土可促进羊肚菌子实体的产生。     

保水剂在翠菊移栽中的应用研究

为解决翠菊移栽后缓苗期长、幼苗生长发育缓慢等问题，试验通过幼苗移栽时蘸根、穴施等方法，进行了保水剂在翠菊移栽中应用效果的研究。试验结果表明：翠菊移栽时使用保水剂，可使缓苗时间缩短2～3d，光合速率提高33．87％～53．23％，叶片水势降低-9．794～-4．897bar。两种处理中，穴施保水剂比用保水剂蘸根效果好。由此可见，在翠菊移栽时适当使用保水剂，是缩短缓苗期、促进翠菊生长发育以及提高抗旱能力的有效途径，值得推广应用。     

蝴蝶兰类原球茎玻璃化产生的原因及恢复效果研究

对蝴蝶兰(Phalaenopsis)组培生产中引起类原球茎玻璃化的原因以及玻璃化类原球茎再利用的效果进行了研究.结果表明,随着植物生长调节剂浓度增高和继代培养的时间延长,类原球茎玻璃化程度加重.当NAA浓度为5 mg/L、BA浓度为10 mg/L,继代培养到第9代时,2种培养基中玻璃化率分别高达71%和65%.玻璃化类原球茎的平均增殖率仅为2.2,再生植株率为183株/瓶,明显低于正常类原球茎的5.3和1 297株/瓶.玻璃化类原球茎在无植物生长调节剂培养基中经2～3代恢复培养后,数量下降到0.84%,玻璃化现象可得到明显恢复,恢复后的类原球茎的分化能力和植株生长状态与正常类原球茎一致,无变异现象发生,可继续应用于组培生产.     

平菇菌丝体生长速度与子实体产量的相关性研究

应用生物统计学的方法 ,对 7个供试平菇菌株的菌丝体生长速度与子实体产量进行了相关性分析。结果表明 :母种菌丝体生长速度与子实体产量相关性不显著 ;原种菌丝体生长速度与子实体产量呈负相关性 ;第一潮菇产量与总产量相关性不显著     

桑黄子实体多糖提取工艺及单糖组成研究

通过单因素试验和正交试验,从提取温度、料液比、提取次数、提取时间4个方面研究桑黄子实体多糖提取条件,得出最佳条件为:提取温度95℃,料液比1∶50,提取次数2次,提取时间2h。运用薄层色谱和气相色谱分析单糖组成,日本桑黄子实体多糖的单糖组成为鼠李糖、阿拉伯糖、葡萄糖、甘露糖和半乳糖;韩国桑黄子实体多糖的单糖组成为鼠李糖、阿拉伯糖、木糖、葡萄糖、甘露糖和半乳糖。     

亚低温条件下外源褪黑素和Ca2+对西瓜幼苗生理特性的影响

以西瓜品种8424种子和幼苗为试材,利用人工气候室进行亚低温处理(昼/夜18℃/12℃)20 d,研究外源褪黑素(MT)和Ca²⁺浸种处理对亚低温条件下西瓜种子萌发,西瓜幼苗抗氧化酶SOD、POD和CAT等活性,渗透调节物质可溶性糖和脯氨酸含量的影响。结果表明,亚低温处理的西瓜种子发芽率和发芽势仅为46.5%和40.5%,外源100μmol·L^-1褪黑素和5 mmol·L^-1Ca²⁺复合浸种处理西瓜种子发芽率和发芽势分别达到62.3%和58.5%。外源褪黑素和Ca²⁺浸种处理显著提高了抗氧化酶SOD、POD、CAT和APX活性,促进了渗透调节物质可溶性糖和脯氨酸的积累,有效缓解亚低温对西瓜种子萌发和幼苗生长影响;褪黑素和Ca²⁺复合浸种西瓜幼苗在出苗第20天时植株鲜质量达到8.21 g·株^-1,达到对照处理的85.5%。综上,外源褪黑素和Ca²⁺能通过提高西瓜幼苗抗氧化酶活性和渗透调节能力等,缓解亚低温的不良影响,促进西瓜幼苗生长。