Nitric oxide regulates the heart by spatial confinement of nitric oxide synthase isoforms

Subcellular localization of nitric oxide (NO) synthases with effector molecules is an important regulatory mechanism for NO signalling. In the heart, NO inhibits L-type Ca2+ channels but stimulates sarcoplasmic reticulum (SR) Ca2+ release, leading to variable effects on myocardial contractility. Here we show that spatial confinement of specific NO synthase isoforms regulates this process. Endothelial NO synthase (NOS3) localizes to caveolae, where compartmentalization with beta-adrenergic receptors and L-type Ca2+ channels allows NO to inhibit beta-adrenergic-induced inotropy. Neuronal NO synthase (NOS1), however, is targeted to cardiac SR. NO stimulation of SR Ca2+ release via the ryanodine receptor (RyR) in vitro, suggests that NOS1 has an opposite, facilitative effect on contractility. We demonstrate that NOS1-deficient mice have suppressed inotropic response, whereas NOS3-deficient mice have enhanced contractility, owing to corresponding changes in SR Ca2+ release. Both NOS1-/- and NOS3-/- mice develop age-related hypertrophy, although only NOS3-/- mice are hypertensive. NOS1/3-/- double knockout mice have suppressed beta-adrenergic responses and an additive phenotype of marked ventricular remodelling. Thus, NOS1 and NOS3 mediate independent, and in some cases opposite, effects on cardiac structure and function.     

Transient aggregation of ubiquitinated proteins during dendritic cell maturation

Dendritic cells (DCs) are antigen-presenting cells with the unique capacity to initiate primary immune responses. Dendritic cells have a remarkable pattern of differentiation (maturation) that exhibits highly specific mechanisms to control antigen presentation restricted by major histocompatibility complex (MHC). MHC class I molecules present to CD8(+) cytotoxic T cells peptides that are derived mostly from cytosolic proteins, which are ubiquitinated and then degraded by the proteasome. Here we show that on inflammatory stimulation, DCs accumulate newly synthesized ubiquitinated proteins in large cytosolic structures. These structures are similar to, but distinct from, aggresomes and inclusion bodies observed in many amyloid diseases. Notably, these dendritic cell aggresome-like induced structures (DALIS) are transient, require continuous protein synthesis and do not affect the ubiquitin-proteasome pathway. Our observations suggest the existence of an organized prioritization of protein degradation in stimulated DCs, which is probably important for regulating MHC class I presentation during maturation.     

The Ontological Constitution of Bounding-Judging in the Phenomenological Epistemology of von Bertalanffy's General System Theory

An analysis of the current presentation of boundary judgments in the Critical Systems literature highlights a general result: that the activity of bounding has been, implicitly or explicitly, considered as an epistemological issue. By arguing that knowledge is not produced singularly by bounding, the paper informs this general result. This, in turn, informs other results, which have emerged in current understanding. In particular, the paper argues (a) the reason why knowledge indeed never attains the status of "objective or right" knowledge, (b) how critique is dependent on some positing of knowledge, and (c) the exact place where critique is actioned. von Bertalanffy's attempted systems epistemology is considered at length because it explains and informs the epistemological conclusions seen to have been drawn in the current Critical Systems literature. von Bertalanffy's attempt requires the support of Husserlian phenomenology, especially Sartre's understanding of it. This requires an in-depth discussion of the phenomenological understanding of consciousness. Since the conclusions stem from von Bertalanffy, the paper reconsiders the status of General System Theory in Critical Systems Thinking.     

The Ontological Status of Critique

Two previous papers by the author are summarized in order to provide the context for the arguments and results of the present paper. The author's previous research has identified the exact place where critique is epistemologically actioned and this enables the present paper to argue for the attribution of ontological status to critique. Since it is commonly acknowledged that a lack of critique results in dogmatism or bounded rationality, these latter two are investigated—in greater depth than previously considered in the literature—and, though they are shown to be inescapable, they provide a route toward a fundamental principle which systemically brings together ontological, epistemological, ethical, and emancipatory concerns. The principle can be stated as follows: One is more or less emancipated depending upon the extent to which one is aware of critique-bounded emancipation as an ontological necessity and thus to the degree to which one ceases to attempt escaping from practical critique into the realms of dogmatic emancipation and rationally bounded emancipation. The paper provides accurate definitions of critique and emancipation, showing that one cannot be considered without the other, thus framing the manner in which further discussion of these two intimately related issues can be continued. In keeping with the author's previous published research, the relevance of von Bertalanffy's deliberations to Critical Systems Thinking, as well as Sartre's philosophy to systems thinking in general, is upheld.     

三轴超形变核态的实验证据

利用轴对称超形变和三轴超形变模型研究了１６５Ｌｕπ［６６０１／２］带两种模型计算的γ跃迁能量都能较好地符合实验值,然而,能量的ｓｉｇｎａｔｕｒｅ颤动指数、三轴因子、两类动力学电四极矩之比却存在明显的差别,这些差别可以用来识别三轴超形变核态     

Optimization of the Chemical Composition of Cast Iron Used for Casting Ball Bearing Grinding Disks

The chemical composition of cast iron used for casting ball bearing machining disks was varied to optimize the properties such as castability, hardenability, and durability in ball machining. The cast iron characteristics were most strongly dependent on the Ni content and the carbon saturation degree, So. This paper describes the types of test specimens, the working conditions, and the experimental results. The increase of the degree of carbon saturation reduces the tendency to form shrinkholes in the castings. The decrease in the Ni content negatively affects the final hardening treatment. A way to control solidification defects in cast iron, by reducing the Ni content, has been verified on cast disks.     

Mutations in PTPN11, encoding the protein tyrosine phosphatase SHP-2, cause Noonan syndrome.

Noonan syndrome (MIM 163950) is an autosomal dominant disorder characterized by dysmorphic facial features, proportionate short stature and heart disease (most commonly pulmonic stenosis and hypertrophic cardiomyopathy). Webbed neck, chest deformity, cryptorchidism, mental retardation and bleeding diatheses also are frequently associated with this disease. This syndrome is relatively common, with an estimated incidence of 1 in 1,000-2,500 live births. It has been mapped to a 5-cM region (NS1) [corrected] on chromosome 12q24.1, and genetic heterogeneity has also been documented. Here we show that missense mutations in PTPN11 (MIM 176876)-a gene encoding the nonreceptor protein tyrosine phosphatase SHP-2, which contains two Src homology 2 (SH2) domains-cause Noonan syndrome and account for more than 50% of the cases that we examined. All PTPN11 missense mutations cluster in interacting portions of the amino N-SH2 domain and the phosphotyrosine phosphatase domains, which are involved in switching the protein between its inactive and active conformations. An energetics-based structural analysis of two N-SH2 mutants indicates that in these mutants there may be a significant shift of the equilibrium favoring the active conformation. This implies that they are gain-of-function changes and that the pathogenesis of Noonan syndrome arises from excessive SHP-2 activity.