Cellular internalization of proinsulin C-peptide

Proinsulin C-peptide is known to bind specifically to cell membranes and to exert intracellular effects, but whether it is internalized in target cells is unknown. In this study, using confocal microscopy and immunostained or rhodamine-labeled peptide, we show that C-peptide is internalized and localized to the cytosol of Swiss 3T3 and HEK-293 cells. In addition, transport into nuclei was found using the labeled peptide. The internalization was followed at 37°C for up to 1 h, and was reduced at 4°C and after preincubation with pertussis toxin. Hence, it is concluded to occur via an energy-dependent, pertussis toxin-sensitive mechanism and without detectable degradation within the experimental time course. Surface plasmon resonance measurements demonstrated binding of HEK-293 cell extract components to C-peptide, and subsequent elution of bound material revealed the components to be intracellular proteins. The identification of C-peptide cellular internalization, intracellular binding proteins, absence of rapid subsequent C-peptide degradation and apparent nuclear internalization support a maintained activity similar to that of an intracrine peptide hormone. Hence, the data suggest the possibility of one further C-peptide site of action. Received 31 October 2006; received after revision 27 December 2006; accepted 30 December 2006     

内电解法处理工业废水的研究进展

综合近十几年国内外有关内电解法废水处理技术研究文献 ,综述了内电解在理论、实践应用方面的研究现状 .对内电解的反应机理、铁屑改性、助剂和催化剂的选用、内电解处理设备的研制等方面进行了研究 ,并对内电解法在目前研究中存在的问题及今后的研究方向做了进一步探讨     

集成Intserv Diffserv 和MPLS改善IP QoS

讨论了 Intserv,Diffserv和 MPLS集成模型的功能及服务类型之间的映射。在边缘网络使用 RSVP,在核心网络使用 CR- LDP作信令协议进行资源预留或建立交换路径 ,对核心网络中的标记边缘路由器 LER和标记交换路由器 LSR的结构和功能进行了设计和说明     

Forecast robustness in macroeconometric models

This paper investigates potential invariance of mean forecast errors to structural breaks in the data generating process. From the general forecasting literature, such robustness is expected to be a rare occurrence. With the aid of a stylized macro model we are able to identify some economically relevant cases of robustness and to interpret them economically. We give an interpretation in terms of co‐breaking. The analytical results resound well with the forecasting record of a medium‐scale econometric model of the Norwegian economy.     

Mutations in the PCNA-binding domain of CDKN1C cause IMAGe syndrome

IMAGe syndrome (intrauterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenita and genital anomalies) is an undergrowth developmental disorder with life-threatening consequences. An identity-by-descent analysis in a family with IMAGe syndrome identified a 17.2-Mb locus on chromosome 11p15 that segregated in the affected family members. Targeted exon array capture of the disease locus, followed by high-throughput genomic sequencing and validation by dideoxy sequencing, identified missense mutations in the imprinted gene CDKN1C (also known as P57KIP2) in two familial and four unrelated patients. A familial analysis showed an imprinted mode of inheritance in which only maternal transmission of the mutation resulted in IMAGe syndrome. CDKN1C inhibits cell-cycle progression, and we found that targeted expression of IMAGe-associated CDKN1C mutations in Drosophila caused severe eye growth defects compared to wild-type CDKN1C, suggesting a gain-of-function mechanism. All IMAGe-associated mutations clustered in the PCNA-binding domain of CDKN1C and resulted in loss of PCNA binding, distinguishing them from the mutations of CDKN1C that cause Beckwith-Wiedemann syndrome, an overgrowth syndrome.     

Management and Employees’ Collaboration: Is the Norwegian Work Life Model Suited for All?

Norway’s work life is known for its strong emphasis on the collaboration between employees, unions and managers. This article explores two case studies: two companies who are part of the same group of companies with the same owners, who are introducing broad collaboration. The same process was used to change employees’ participation in the development processes, but the results were different for each company. In this article we explore the factors that influence the implementation of broad collaboration between employees, unions and managers in the light of the Norwegian work life model and of the regional traditions. When introducing new collaboration patterns between managers, union and employees in a company, it is important to take regional traditions into consideration. One of the companies succeeded in implementing direct manager-employee collaboration, and the other company failed to implement broad collaboration. This article explores the reasons behind the different results. It further explores the experience from the two cases, and asks the question is the Norwegian work life model suited for all? The article suggests strategies for how to create an environment for broad collaboration in companies that have no such tradition.     

A Note on Knowledge Creation in Open-Source Software Projects: What Can We Learn from Luhmann’s Theory of Social Systems?

We use the sociological systems theory proposed by Niklas Luhmann to complement a socially-oriented view of knowledge with the role of technical infrastructure in knowledge creation. We highlight the self-referential character of knowledge creation and draw upon illustrative examples from open-source software. We discuss why knowledge creation processes are often prone to breakdown and propose three conditions that may stabilize knowledge creation processes: perceptibility, systemic memory, and modularity.     

猴头菌降解木质纤维素的研究

从四株猴头菌在培养期间对木质素、半纤维素,纤维素的降解和有关酶活变化的规律进行研究。结果表明: 木质素降解量大于半纤维素降解量,半纤维素降解量大于纤维素降解量。不同菌株木质素分解活性不同,木质素分解活性强的菌株,半纤维素和纤维素的降解也较多,羧甲基纤维素酶活性和滤纸酶活性大体一致。胞外多酚氧化酶活性以培养最初期为高,后期活性很低,但子实体中的多酚氧化酶活性很高,以原基期为最高。这表明子实体中的多酚氧酶是在子实体中产生的,而不是在菌丝体中产生而后输送到子实体中去的。     

沉淀二氧化硅载银抗菌剂的制备及其抗菌性能

以沉淀二氧化硅为载体，吸附硝酸银后，在500℃下灼烧，制备了具有抗菌功能的线银沉淀二氧化硅抗菌剂，并检验了其抗菌性能；还对抗菌剂的抗菌机理进行了初步探讨。测试结果表明，沉淀二氧化硅的载银量在7％以上时，所制备的抗菌剂对绿脓杆菌、大肠杆菌和枯草杆菌的杀菌率达到100％，具有优异的抗菌性能，可用于抗菌塑料、抗菌食品包装、抗菌卫生纸和抗菌纺织制品等领域。