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Background Endothelium-derived nitric oxide plays an important role for the bone marrow microenvironment. Since several important effects of nitric oxide are mediated by cGMP-dependent pathways, we investigated the role of the cGMP downstream effector cGMP-dependent protein kinase I (cGKI) on postnatal neovascularization. Methodology/Principal Findings In a disc neovascularization model, cGKI -/- mice showed an impaired neovascularization as compared to their wild-type (WT) littermates. Infusion of WT, but not cGKI -/- bone marrow progenitors rescued the impaired ingrowth of new vessels in cGKI-deficient mice. Bone marrow progenitors from cGKI -/- mice showed reduced proliferation and survival rates. In addition, we used cGKI alpha leucine zipper mutant (LZM) mice as model for cGKI deficiency. LZM mice harbor a mutation in the cGKI alpha leucine zipper that prevents interaction with downstream signaling molecules. Consistently, LZM mice exhibited reduced numbers of vasculogenic progenitors and impaired neovascularization following hindlimb ischemia compared to WT mice. Conclusions/Significance Our findings demonstrate that the cGMP-cGKI pathway is critical for postnatal neovascularization and establish a new role for cGKI in vasculogenesis, which is mediated by bone marrow-derived progenitors.
Background Parkinson's disease (PD) is an adult-onset movement disorder of largely unknown etiology. We have previously shown that loss-of-function mutations of the mitochondrial protein kinase PINK1 (PTEN induced putative kinase 1) cause the recessive PARK6 variant of PD. Methodology/Principal Findings Now we generated a PINK1 deficient mouse and observed several novel phenotypes: A progressive reduction of weight and of locomotor activity selectively for spontaneous movements occurred at old age. As in PD, abnormal dopamine levels in the aged nigrostriatal projection accompanied the reduced movements. Possibly in line with the PARK6 syndrome but in contrast to sporadic PD, a reduced lifespan, dysfunction of brainstem and sympathetic nerves, visible aggregates of alpha-synuclein within Lewy bodies or nigrostriatal neurodegeneration were not present in aged PINK1-deficient mice. However, we demonstrate PINK1 mutant mice to exhibit a progressive reduction in mitochondrial preprotein import correlating with defects of core mitochondrial functions like ATP-generation and respiration. In contrast to the strong effect of PINK1 on mitochondrial dynamics in Drosophila melanogaster and in spite of reduced expression of fission factor Mtp18, we show reduced fission and increased aggregation of mitochondria only under stress in PINK1-deficient mouse neurons. Conclusion Thus, aging Pink1 -/- mice show increasing mitochondrial dysfunction resulting in impaired neural activity similar to PD, in absence of overt neuronal death.
The C-module-binding factor (CbfA) is a multidomain protein that belongs to the family of jumonji-type (JmjC) transcription regulators. In the social amoeba Dictyostelium discoideum, CbfA regulates gene expression during the unicellular growth phase and multicellular development. CbfA and a related D. discoideum CbfA-like protein, CbfB, share a paralogous domain arrangement that includes the JmjC domain, presumably a chromatin-remodeling activity, and two zinc finger-like (ZF) motifs. On the other hand, the CbfA and CbfB proteins have completely different carboxy-terminal domains, suggesting that the plasticity of such domains may have contributed to the adaptation of the CbfA-like transcription factors to the rapid genome evolution in the dictyostelid clade. To support this hypothesis we performed DNA microarray and real-time RT-PCR measurements and found that CbfA regulates at least 160 genes during the vegetative growth of D. discoideum cells. Functional annotation of these genes revealed that CbfA predominantly controls the expression of gene products involved in housekeeping functions, such as carbohydrate, purine nucleoside/nucleotide, and amino acid metabolism. The CbfA protein displays two different mechanisms of gene regulation. The expression of one set of CbfA-dependent genes requires at least the JmjC/ZF domain of the CbfA protein and thus may depend on chromatin modulation. Regulation of the larger group of genes, however, does not depend on the entire CbfA protein and requires only the carboxy-terminal domain of CbfA (CbfA-CTD). An AT-hook motif located in CbfA-CTD, which is known to mediate DNA binding to A+T-rich sequences in vitro, contributed to CbfA-CTD-dependent gene regulatory functions in vivo.
Background Transplantation of vasculogenic progenitor cells (VPC) improves neovascularization after ischemia. However, patients with type 2 diabetes mellitus show a reduced VPC number and impaired functional activity. Previously, we demonstrated that p38 kinase inhibition prevents the negative effects of glucose on VPC number by increasing proliferation and differentiation towards the endothelial lineage in vitro. Moreover, the functional capacity of progenitor cells is reduced in a mouse model of metabolic syndrome including type 2 diabetes (Leprdb) in vivo. Findings The aim of this study was to elucidate the underlying signalling mechanisms in vitro and in vivo. Therefore, we performed DNA-protein binding arrays in the bone marrow of mice with metabolic syndrome, in blood-derived progenitor cells of diabetic patients as well as in VPC ex vivo treated with high levels of glucose. The transcriptional activation of ETS transcription factors was increased in all samples analyzed. Downregulation of ETS1 expression by siRNA abrogated the reduction of VPC number induced by high-glucose treatment. In addition, we observed a concomitant suppression of the non-endothelial ETS-target genes matrix metalloproteinase 9 (MMP9) and CD115 upon short term lentiviral delivery of ETS-specific shRNAs. Long term inhibition of ETS expression by lentiviral infection increased the number of cells with the endothelial markers CD144 and CD105. Conclusion These data demonstrate that diabetes leads to dysregulated activation of ETS, which blocks the functional activity of progenitor cells and their commitment towards the endothelial cell lineage.
Blood oxygen level-dependent (BOLD) responses were measured in parts of primary visual cortex that represented unstimulated visual field regions at different distances from a stimulated central target location. The composition of the visual scene varied by the presence or absence of additional peripheral distracter stimuli. Bottom-up effects were assessed by comparing peripheral activity during central stimulation vs. no stimulation. Top-down effects were assessed by comparing active vs. passive conditions. In passive conditions subjects simply watched the central letter stimuli and in active conditions they had to report occurrence of pre-defined targets in a rapid serial letter stream. Onset of the central letter stream enhanced activity in V1 representations of the stimulated region. Within representations of the periphery activation decreased and finally turned into deactivation with increasing distance from the stimulated location. This pattern was most pronounced in the active conditions and during the presence of peripheral stimuli. Active search for a target did not lead to additional enhancement at areas representing the attentional focus but to a stronger deactivation in the vicinity. Suppressed neuronal activity was also found in the non distracter condition suggesting a top-down attention driven effect. Our observations suggest that BOLD signal decreases in primary visual cortex are modulated by bottom-up sensory-driven factors such as the presence of distracters in the visual field as well as by top-down attentional processes.
Mammalian retinae have rod photoreceptors for night vision and cone photoreceptors for daylight and colour vision. For colour discrimination, most mammals possess two cone populations with two visual pigments (opsins) that have absorption maxima at short wavelengths (blue or ultraviolet light) and long wavelengths (green or red light). Microchiropteran bats, which use echolocation to navigate and forage in complete darkness, have long been considered to have pure rod retinae. Here we use opsin immunohistochemistry to show that two phyllostomid microbats, Glossophaga soricina and Carollia perspicillata, possess a significant population of cones and express two cone opsins, a shortwave-sensitive (S) opsin and a longwave-sensitive (L) opsin. A substantial population of cones expresses S opsin exclusively, whereas the other cones mostly coexpress L and S opsin. S opsin gene analysis suggests ultraviolet (UV, wavelengths <400 nm) sensitivity, and corneal electroretinogram recordings reveal an elevated sensitivity to UV light which is mediated by an S cone visual pigment. Therefore bats have retained the ancestral UV tuning of the S cone pigment. We conclude that bats have the prerequisite for daylight vision, dichromatic colour vision, and UV vision. For bats, the UV-sensitive cones may be advantageous for visual orientation at twilight, predator avoidance, and detection of UV-reflecting flowers for those that feed on nectar.
Introduction Chemokines and their receptors control immune cell migration during infections as well as in autoimmune responses. A 32 bp deletion in the gene of the chemokine receptor CCR5 confers protection against HIV infection, but has also been reported to decrease susceptibility to rheumatoid arthritis (RA). The influence of this deletion variant on the clinical course of this autoimmune disease was investigated. Methods Genotyping for CCR5d32 was performed by PCR and subsequent electrophoretic fragment length determination. For the clinical analysis, the following extra-articular manifestations of RA were documented by the rheumatologist following the patient: presence of rheumatoid nodules, major organ vasculitis, pulmonary fibrosis, serositis or a Raynaud's syndrome. All documented CRP levels were analyzed retrospectively, and the last available hand and feet radiographs were analyzed with regards to the presence or absence of erosive disease. Results Analysis of the CCR5 polymorphism in 503 RA patients and in 459 age-matched healthy controls revealed a significantly decreased disease susceptibility for carriers of the CCR5d32 deletion (Odds ratio 0.67, P = 0.0437). Within the RA patient cohort, CCR5d32 was significantly less frequent in patients with extra-articular manifestations compared with those with limited, articular disease (13.2% versus 22.8%, P = 0.0374). In addition, the deletion was associated with significantly lower average CRP levels over time (median 8.85 vs. median 14.1, P = 0.0041) and had a protective effect against the development of erosive disease (OR = 0.40, P = 0.0047). Intriguingly, homozygosity for the RA associated DNASE2 -1066 G allele had an additive effect on the disease susceptibility conferred by the wt allele of CCR5 (OR = 2.24, P = 0.0051 for carrier of both RA associated alleles) Conclusions The presence of CCR5d32 significantly influenced disease susceptibility to and clinical course of RA in a German study population. The protective effect of this deletion, which has been described to lead to a decreased receptor expression in heterozygous patients, underlines the importance of chemokines in the pathogenesis of RA.
Objective. A study supported by the EULAR and the ACR being conducted to establish classification criteria for polymyalgia rheumatica (PMR) will include ultrasound examination of the shoulders and hips. Ultrasound (US) depicts glenohumeral joint effusion, biceps tenosynovitis, subdeltoid bursitis, hip joint synovitis, and trochanteric bursitis in PMR. These findings may aid in distinguishing PMR from other diseases. The purpose of this study was to assess standards and US interreader agreement of participants in the PMR classification criteria study. Methods. Sixteen physicians in four groups examined shoulders and hips of 4 patients and 4 healthy adults with ultrasound. Overall agreement and interobserver agreement were calculated. Results. The overall agreement (OA) between groups was 87%. The OA for healthy shoulders was 88.8%, for healthy hips 100%, for shoulders with pathology 85.2%, and 74.3% for hips with pathology, respectively. Conclusion. There was a high degree of agreement found for the examination of healthy shoulders and pathologic hips. Agreement was moderate for pathologic shoulders and perfect for healthy hips. US of shoulder and hips performed by different examiners is a reliable and feasible tool for assessment of PMR related disease pathology and can be incorporated into a classification criteria study.
Representations of the unknown and the foreign can be found in every culture. Paralleling the method of constructing identity in relation to the Other, all cultures create myths about the ‘foreign’ in order to discern what the ‘native’ is, and thus often essentialize them as either good or bad, ultimately to vindicate one’s own actions and values. The nature of myths has it as such that they lend themselves to images, which are easily transformed into representations. Representations of the foreign in the United States follow the same purpose; they are propagated to define the nation’s identity and set it into political and cultural relation to other nations and civilizations. In this thesis’ context, then, representations of Asian Americans in American culture strengthen the imaginative bonds of American national identity manifesto. However, the interdependency of the Self and the Other clarifies and further entangles the subjects that constitute American national identity and in turn legitimizes the belated claim of Asian Americans to be included into it. Asian American literature is primarily concerned with these myths and (mis)representations that are influenced by Orientalist images in Western culture. Thus, Orientalism – a constructed myth about the Orient, which exists in art, books, and armchair theories of all kinds in the Western world – becomes the main motif for Asian American literature. If we construe this theory a little further then Asian American identity is formed in relation to Orientalist representations that need to be deconstructed first. From the outset, if Orientalism is considered as a produce of imperialism, it seems that time is a defining factor in Orientalism, both as an agent of change and as a factor of perspective. In reality, however, Orientalism seems resilient to time and change; the creation of the Madame Butterfly myth exemplifies what was created in 1887 had been perfected by 1900 and since then enjoys frequent comebacks until today. Thus, for Asian American artists and writers to dismantle Orientalist stereotypes begins a literally archaeological process: excavating the leftovers of American Orientalism, evaluating those finds, and re-relating them with their own cultural and historical actuality. Rather than producing a neat line of argumentation, the approaches on defining Asian American identity within the American national identity manifesto fall into unwieldy clusters and even get tangled up into self-contradictions. The methods of dismantling Orientalist stereotypes are manifold and range from total rejection over evocation and appropriation to reflection. In order to wrestle such disparate issues Orientalism produces in Asian American Literature into an organic whole, it was important to focus consistently on the over arching theme of American national identity. As this thesis aims to show, Orientalist issues that are dealt with in Asian American literature all point toward the greater aim of national inclusion. This thesis is grouped into two parts. PART I provides historical and theoretical background information necessary to understand Orientalist issues in contemporary Asian American literature. Analogous to Asian American writers that feel the necessity to bed their work into the correct historical frame in order to prevent misunderstanding, chapters two and three serve to couch my argument into the correct frame. The theoretical base work is laid with Edward Said’s Orientalism and its implementation on the American and Asian American context. PART II examines literary examples, applying the theorems discussed in PART I. Chapter four is a close analysis of the submissive Butterfly stereotype that has, since its appearance in late nineteenth century, moved, inspired and even outraged writers. Beginning with the literary development of Madame Butterfly, D. H. Hwang’s deconstructivist M. Butterfly gives new perspectives on Orientalism by redefining gender and racial roles. To complement my analysis, in chapter five, I try to trace current Asian American reactions to Orientalism. Texts by comedian Margaret Cho and poet Beau Sia serve as examples of analysis. As a result of the disparate narrative forms of the analyzed works and the unevenness of scholarship on twenty-first century, the analyses vary greatly in scope and detail. In choosing fairly young narrative forms like stand-up comedy and spoken word poetry I want to emphasize how Orientalism pertains to the question of Asian American identity. To close the circle of my discourse I will go back to where I start my thesis: Asian Americans and their position within America’s national identity discourse. It is noteworthy that until today, Asian American identity remains a hostage of these Orientalist stereotypes that mark the boundaries of their American identity.
Volatile organic compounds (VOCs) were analyzed in air and snow samples at the Jungfraujoch high alpine research station in Switzerland as part of CLACE 5 (CLoud and Aerosol Characterization Experiment) during February/March 2006. The fluxes of individual compounds in ambient air were calculated from gas phase concentrations and wind speed. The highest concentrations and flux values were observed for the aromatic hydrocarbons benzene (14.3 μg.m−2 s−1), 1,3,5-trimethylbenzene (5.27 μg.m−2 s−1), toluene (4.40 μg.m−2 −1), and the aliphatic hydrocarbons i-butane (7.87 μg.m−2 s−1), i-pentane (3.61 μg.m−2 s−1) and n-butane (3.23 μg.m−2 s−1). The measured concentrations and fluxes were used to calculate the efficiency of removal of VOCs by snow, which is defined as difference between the initial and final concentration/flux values of compounds before and after wet deposition. The removal efficiency was calculated at −24°C (−13.7°C) and ranged from 37% (35%) for o-xylene to 93% (63%) for i-pentane. The distribution coefficients of VOCs between the air and snow phases were derived from published poly-parameter linear free energy relationship (pp-LFER) data, and compared with distribution coefficients obtained from the simultaneous measurements of VOC concentrations in air and snow at Jungfraujoch. The coefficients calculated from pp-LFER exceeded those values measured in the present study, which indicates more efficient snow scavenging of the VOCs investigated than suggested by theoretical predictions.
A characterization of the ultra-fine aerosol particle counter COPAS (COndensation PArticle counting System) for operation on board the Russian high altitude research aircraft M-55 Geophysika is presented. The COPAS instrument consists of an aerosol inlet and two dual-channel continuous flow Condensation Particle Counters (CPCs) operated with the chlorofluorocarbon FC-43. It operates at pressures between 400 and 50 hPa for aerosol detection in the particle diameter (dp) range from 6 nm up to 1 micro m. The aerosol inlet, designed for the M-55, is characterized with respect to aspiration, transmission, and transport losses. The experimental characterization of counting efficiencies of three CPCs yields dp50 (50% detection particle diameter) of 6 nm, 11 nm, and 15 nm at temperature differences (DeltaT) between saturator and condenser of 17°C, 30°C, and 33°C, respectively. Non-volatile particles are quantified with a fourth CPC, with dp50=11 nm. It includes an aerosol heating line (250°C) to evaporate H2SO4-H2O particles of 11 nm<dp<200 nm at pressures between 70 and 300 hPa. An instrumental in-flight inter-comparison of the different COPAS CPCs yields correlation coefficients of 0.996 and 0.985. The particle emission index for the M-55 in the range of 1.4–8.4×10 16 kg -1 fuel burned has been estimated based on measurements of the Geophysika's own exhaust.
Medium range hydrological forecasts in mesoscale catchments are only possible with the use of hydrological models driven by meteorological forecasts, which in particular contribute quantitative precipitation forecasts (QPF). QPFs are accompanied by large uncertainties, especially for longer lead times, which are propagated within the hydrometeorological model system. To deal with this limitation of predictability, a probabilistic forecasting system is tested, which is based on a hydrological-meteorological ensemble prediction system. The meteorological component of the system is the operational limited-area ensemble prediction system COSMO-LEPS that downscales the global ECMWF ensemble to a horizontal resolution of 10 km, while the hydrological component is based on the semi-distributed hydrological model PREVAH with a spatial resolution of 500 m.
Earlier studies have mostly addressed the potential benefits of hydrometeorological ensemble systems in short case studies. Here we present an analysis of hydrological ensemble hindcasts for two years (2005 and 2006). It is shown that the ensemble covers the uncertainty during different weather situations with appropriate spread. The ensemble also shows advantages over a corresponding deterministic forecast, even under consideration of an artificial spread.
It has been shown that certain chemokine receptor polymorphisms may correspond to certain complications after organ transplantation. Ischemic-type biliary lesion (ITBL) encounters for major morbidity and mortality in liver transplant recipients. So far, the exact cause for ITBL remains unclear. Certain risk factors for the development of ITBL like donor age and cold ischemic time are well described. In a previous study, a 32-nucleotide deletion of the chemokine receptor-5Delta32 (CCR-5Delta32) was strongly associated with the incidence of ITBL in adult liver transplantation. This study re-evaluates the association of CCR-5Delta32 gene polymorphism and the incidence of ITBL. 169 patients were included into this retrospective analysis. 134 patients were homozygous for wild-type CCR-5, 33 patients heterozygous, and 2 patients were homozygous for CCR-5Delta32 mutation. There were no major differences in donor or recipients demographics. No association was found between CCR-5Delta32 mutation and the development of ITBL.We conclude that CCR-5Delta32 is no risk factor for the development of ITBL in our patient cohort.
The CUG-binding protein 1 (CUG-BP1) is a member of the CUG-BP1 and ETR-like factors (CELF) family or the Bruno-like family and is involved in the control of splicing, translation and mRNA degradation. Several target RNA sequences of CUG-BP1 have been predicted, such as the CUG triplet repeat, the GU-rich sequences and the AU-rich element of nuclear pre-mRNAs and/or cytoplasmic mRNA. CUG-BP1 has three RNA-recognition motifs (RRMs), among which the third RRM (RRM3) can bind to the target RNAs on its own. In this study, we solved the solution structure of the CUG-BP1 RRM3 by hetero-nuclear NMR spectroscopy. The CUG-BP1 RRM3 exhibited a noncanonical RRM fold, with the four-stranded b-sheet surface tightly associated with the N-terminal extension. Furthermore, we determined the solution structure of the CUG-BP1 RRM3 in the complex with (UG)3 RNA, and discovered that the UGU trinucleotide is specifically recognized through extensive stacking interactions and hydrogen bonds within the pocket formed by the b-sheet surface and the N-terminal extension. This study revealed the unique mechanism that enables the CUG-BP1 RRM3 to discriminate the short RNA segment from other sequences, thus providing the molecular basis for the comprehension of the role of the RRM3s in the CELF/Bruno-like family.
Realität – Repräsentation – Öffentlichkeit : der Dokumentarfilm in der heutigen Fernsehlandschaft
(2009)
In dieser Studie wurde die Frage aufgestellt, ob und wie durch einen Fernsehdokumentarfilm im Vergleich zu ethnographischen Darstellungen Wirklichkeit dokumentiert und Wissen über diese vermittelt werden kann. Die Beantwortung der Fragestellung wurde durch eine vergleichende Analyse einzelner Produktionsschritte, wie auch der dahinter stehenden Kriterien und Konventionen auf empirischer und theoretischer Ebene, angestrebt. Ergänzt wurde dies durch eine Evaluation der Rahmenbedingungen, die sich auf die Produktion und vereinzelt auch auf die Konventionen auswirken können.
U1-snRNA is an integral part of the U1 ribonucleoprotein pivotal for pre-mRNA splicing. Toll-like receptor (TLR) signaling has recently been associated with immunoregulatory capacities of U1-snRNA. Using lung A549 epithelial/carcinoma cells, we report for the first time on interferon regulatory factor (IRF)-3 activation initiated by endosomally delivered U1-snRNA. This was associated with expression of the IRF3-inducible genes interferon-b (IFN-b), CXCL10/IP-10 and indoleamine 2,3-dioxygenase. Mutational analysis of the U1-snRNA-activated IFN-b promoter confirmed the crucial role of the PRDIII element, previously proven pivotal for promoter activation by IRF3. Notably, expression of these parameters was suppressed by bafilomycin A1, an inhibitor of endosomal acidification, implicating endosomal TLR activation. Since resiquimod, an agonist of TLR7/8, failed to stimulate A549 cells, data suggest TLR3 to be of prime relevance for cellular activation. To assess the overall regulatory potential of U1-snRNA-activated epithelial cells on cytokine production, co-cultivation with peripheral blood mononuclear cells (PBMC) was performed. Interestingly, A549 cells activated by U1-snRNA reinforced phytohemagglutinin-induced interleukin-10 release by PBMC but suppressed that of tumor necrosis factor-a, indicating an antiinflammatory potential of U1-snRNA. Since U1-snRNA is enriched in apoptotic bodies and epithelial cells are capable of performing efferocytosis, the present data in particular connect to immunobiological aspects of apoptosis at host/environment interfaces.
Background Although current molecular clock methods offer greater flexibility in modelling historical evolutionary events, calibration of the clock with dates from the fossil record is still problematic for many groups. Here we implement several new approaches in molecular dating to estimate evolutionary ages of Lacertidae, an Old World family of lizards with a poor fossil record and uncertain phylogeny. Four different models of rate variation are tested in a new program for Bayesian phylogenetic analysis called TreeTime, based on a combination of mitochondrial and nuclear gene sequences. We incorporate paleontological uncertainty into divergence estimates by expressing multiple calibration dates as a range of probabilistic distributions. We also test the reliability of our proposed calibrations by exploring effects of individual priors on posterior estimates. Results According to the most reliable model, as indicated by Bayes factor comparison, modern lacertids arose shortly after the K/T transition and entered Africa about 45 million years ago, with the majority of their African radiation occurring in the Eocene and Oligocene. Our findings indicate much earlier origins for these clades than previously reported, and we discuss our results in light of paleogeographic trends during the Cenozoic. Conclusions This study represents the first attempt to estimate evolutionary ages of a specific group of reptiles exhibiting uncertain phylogenetic relationships, molecular rate variation and a poor fossil record. Our results emphasize the sensitivity of molecular divergence dates to fossil calibrations, and support the use of combined molecular data sets and multiple, well-spaced dates from the fossil record as minimum node constraints. The bioinformatics program used here, TreeTime, is publicly available, and we recommend its use for molecular dating of taxa faced with similar challenges.
Zwischen Bilateralismus und Multilateralismus : die Zentralasienpolitik der Volksrepublik China
(2009)
Die Außenpolitik der Volksrepublik China (VRC) ist im Wandel begriffen. Nur ein – wenngleich wesentlicher – Ausdruck dessen ist die erst seit wenigen Jahren zu beobachtende Entwicklung, dass sich die VRC vermehrt multilateralen Institutionen zuwendet und diese mittlerweile zum Teil gar selbst initiiert. Dieser Trend stellt eine radikale Kehrtwende gegenüber dem dar, was die VRC seit ihrer Gründung 1949 noch bis weit in die 1990er-Jahre hinein mit Multilateralismus (ML) assoziiert hat – nämlich Mechanismen zur Strafung und Einengung der VRC. Doch welche praktische Bedeutung kommt multilateralen Wirkungsweisen innerhalb der chinesischen Außenpolitik in jüngster Zeit tatsächlich zu? Die vorliegende Magisterarbeit beschäftigt sich mit dieser Fragestellung, indem sie zu analysieren sucht, welche Rolle multilaterale Strukturen – im Gegensatz zu bilateralen – bei der Implementierung chinesischer außenpolitischer Interessen spielen. Dies geschieht anhand eines einzigartigen Fallbeispiels, und zwar der chinesischen Zentralasienpolitik, innerhalb der wiederum die Shanghai Cooperation Organization (SCO) eine herausragende Stellung einnimmt. Diese Organisation ist das einzige multilaterale Forum, an dem die VRC von Beginn an als der maßgebende Akteur im Hinblick auf ideelle, konzeptionelle und inhaltliche Belange teilgenommen hat. Entsprechend ist davon auszugehen, dass die Untersuchung ein Höchstmaß an Einblicken in den tatsächlich intendierten Zweck des chinesischen ML zu liefern vermag. Die Analyse zeigt, dass multilaterale Vorgehensweisen in quantitativer Hinsicht seit Gründung der SCO im Jahre 2001 stark zugenommen haben, und das auf allen vier identifizierten Hauptinteressensgebieten der VRC in Zentralasien: Sicherheit, Wirtschaft, Energie und Geopolitik. Mit Blick auf die qualitative Komponente ist indessen zu konstatieren, dass dem ML, den China in der Region praktiziert, einige negativ behaftete Charakteristika zu eigen sind. Die Attribute „flexibel“, „selektiv“, „flach“ und „instrumentalisiert“, die derzeit weitgehend als prägend für den chinesischen ML in seiner Gesamtheit angesehen werden, besitzen auch – und gerade – in Zentralasien ihre Gültigkeit. Insgesamt fällt auf, dass die VRC multilaterale Strategien nur dann verfolgt, wenn der kurzfristige Eigennutzen über den bilateraler Mechanismen hinausgeht. Und auch dann hört der Rückgriff auf ML dort auf, wo der eigene Gewinn ein Maximum erreicht. Somit bleiben die chinesischen Machthaber den Praxisbeweis einer integrativen Funktion von ML noch schuldig.