Morphine 6 glucuronide stimulates nitric oxide release in mussel neural tissues: evidence for a morphine 6 glucuronide opiate receptor subtype

We have previously demonstrated that Mytilus edulis pedal ganglia contain opiate alkaloids, i.e., morphine and morphine 6 glucuronide (M6G), as well as mu opiate receptor subtype fragments exhibiting high sequence similarity to those found in mammals. Now we demonstrate that M6G stimulates pedal ganglia constitutive nitric oxide (NO) synthase (cNOS)-derived NO release at identical concentrations and to similar peak levels as morphine. However, the classic opiate antagonist, naloxone, only blocked the ability of morphine to stimulate cNOS-derived NO release and not that of M6G. CTOP, a mu-specific antagonist, blocked the ability of M6G to induce cNOS-derived NO release as well as that of morphine, suggesting that a novel mu opiate receptor was present and selective toward M6G. In examining a receptor displacement analysis, both opiate alkaloids displaced [³H]-dihydromorphine binding to the mu opiate receptor subtype. However, morphine exhibited a twofold higher affinity, again suggesting that a novel mu opiate receptor may be present. Received 1 November 2001; received after revision 1 February 2002; accepted 1 February 2002     

现代科学发展需要“T”字型人才

一 现代科学的发展由小科学时代走向大科学时代。其科学的发展特点是朝着微观和宏观两个截然不同的方向发展,即科学的高度分化和高度综合。科学的深度分化,使各门学科越来越专门化,而纵向发展则引起综合科学的发展。学科间的相互联系、相互渗透己成为科学发展的主流。新学科的兴起,促使传统学科的不断分化与解体。全世界每年新生几十种学科、新生上百种技术专业,共发展速度令人吃惊,可谓日新月异,似乎存在“杂交优势”效应。《控制论》创造人维纳曾指出:“在科学发展上可以得到最大收获的领域是各种已经建立起来的部门之间的被忽视的无人区。”在这科学技术迅速发展,知识不断更新,信息量急     

The boundedness of singular integral operator along an open curve

It is well known that, the singular integral operatorS defined as: ifL is a closed smooth contour in the complex plane C, thenS is a bounded linear operator fromH ^μ(L) intoH ^μ(L): ifL is an open smooth curve, thenS is just a linear operator fromH ^* intoH ^*. In this paper, we define a Banach space mu $$ " align="middle" border="0"> , and prove that mu \to H_{\lambda _1 , \lambda _2 }^\mu $$ " align="middle" border="0"> is a bounded linear operator, then verify the boundedness of other kinds of singular integral operators. Supported by the National Science Foundation of China Wang Xiaolin: born in Aug. 1950, Professor     

赖氨酸对果胶酶产生菌Asp.3.396白孢子突变株生长及产酶的影响

果胶酶产生菌Asp,3.396经辐射诱变,筛选出一株白色孢子突变株,该突变株孢子为白色,酶液的色泽较浅,此种突变株性状有利于果品加工工艺,可提高果汁果酒等产品质量,但该突变株生长周期较长,产酶性能不稳定,当培养基内加入赖氨酸后,此突变株生长发育好,产酶期提前,产酶性能稳定,其酶液加入到苹果等五种果实后,显著提高了出汁率,并对草莓和柑桔果实的果汁澄清度也有所提高。     

栉孔扇贝消化系统μ受体的免疫组化定位研究

采用免疫组织化学定位的方法研究了μ受体在栉孔扇贝(Chlamys farreri)消化系统的分布,结果表明:口唇上皮的大量皱褶呈μ受体阳性,少量皱褶呈μ受体强阳性,口唇结缔组织呈弱阳性或阳性;唇瓣表皮大量部位呈μ受体阳性,少量部位呈μ受体强阳性,唇瓣结缔组织呈阳性或弱阳性,结缔组织内有少量神经纤维呈阳性;胃上皮表面呈μ受体阳性,胃上皮内部呈μ受体弱阳性;肠粘膜上皮有大量μ受体阳性颗粒和弱阳性颗粒分布;直肠上皮有少量皱褶表面呈μ受体弱阳性;肝小叶中的少量细胞呈μ受体阳性,大量细胞呈μ受体强阳性,肝小叶间结缔组织呈强阳性或阳性.     

基于3S的贵州省万亩大坝信息提取技术

坝子(山间平坝)是贵州农业的发祥地,也是聚落、工矿和交通线发展的主要场所,但其面积(包括河谷平坝)仅占全省总面积的3%(据《贵州国土资源》1987.2)。其中万亩(666.7hm2)以上的大坝到底有多少,在历来统计资料和相关论述中却从未有过确切数值,但这一直是上级领导部门和全省人民所关心的一个重要数据。为此,在3S技术的支持下,对贵州省万亩大坝信息进行了提取和验证,取得了客观而又详实的数据,更新了贵州省万亩大坝信息,从而为政府决策和土地资源管理与利用提供了可靠的数据和有利的支持。     

The Application of Multi-level Fuzzy Judgement in the Appraisement of Green Products

The appraisement of “the green level“ for a green p ro duct is a problem that has to deal with multi-aspect and multi-stratification. According to the property of the items that affect “the green level“ of the pro duct, they can be divided into aspects, elements and factors. These make appreci able grades. The multi-level fuzzy judgement can solve the appraisement problem that considers the influences of design, manufacture, use and recovery in all- life cycle or multi-life cycle of product. In the judgin...     

Differential use of an in-frame translation initiation codon regulates human mu opioid receptor (OPRM1)

The pharmacological effects of morphine and morphine-like drugs are mediated primarily through the μ opioid receptor. Here we show that differential use of an in-frame translational start codon in the 5′-untranslated region of the OPRM1 generates different translational products in vivo and in vitro. The 5′-end of the OPRM1 gene is necessary for initiating the alternate form and for subsequent degradation of the protein. Initiation of OPRM1 at the upstream site decreases the initiation at the main AUG site. However, alternative initiation of the long form of OPRM1 produces a protein with a short half-life, resulting from degradation mediated by the ubiquitin–proteasome pathway. Reporter and degradation assays showed that mutations of this long form at the second and third lysines reduce ubiquitin-dependent proteasome degradation, stabilizing the protein. The data suggest that MOP expression is controlled in part by initiation of the long form of MOP at the alternate site.     

L^2（R）的双正交向量小波包分解

对双正交向量小波的性质进行了探讨,给出了双正交向量小波包的定义及其性质,作出平方可积空间Ｌ＾２（Ｒ）的双正向量小波包分解。