New insights into the anti-inflammatory actions of aspirin- induction of nitric oxide through the generation of epi-lipoxins

Aspirin has always remained an enigmatic drug. Not only does it present with new benefits for treating an ever-expanding list of apparently unrelated diseases at an astounding rate but also because aspirin enhances our understanding of the nature of these diseases processe. Originally, the beneficial effects of aspirin were shown to stem from its inhibition of cyclooxygenase-derived prostaglandins, fatty acid metabolites that modulate host defense. However, in addition to inhibiting cyclooxygenase activity aspirin can also inhibit pro-inflammatory signaling pathways, gene expression and other factors distinct from eicosanoid biosynthesis that drive inflammation as well as enhance the synthesis of endogenous protective anti-inflammatory factors. Its true mechanism of action in anti-inflammation remains unclear. Here the data from a series of recent experiments proposing that one of aspirin's predominant roles in inflammation is the induction of nitric oxide, which potently inhibits leukocyte/endothelium interaction during acute inflammation, will be discussed. It will be argued that this nitric oxide-inducing effects are exclusive to aspirin due to its unique ability, among the family of traditional anti-inflammatory drugs, to acetylate the active site of inducible cyclooxygenase and generate a family of lipid mediators called the epi-lipoxins that are increasingly being shown to have profound roles in a range of host defense responses.

Watching television: a previously unrecognized powerful trigger of λ waves.

OBJECTIVE: To assess whether lambda waves are elicited by watching television (TV) and their association with demographical and EEG features. METHODS: We retrospectively compared lambda wave occurrence in prolonged EEG monitorings of outpatients who were allowed to watch TV and in standard EEGs recorded in TV-free rooms. All EEGs were interpreted by the same two electroencephalographers. RESULTS: Of 2,072 standard EEG reports, 36 (1.7 %) mentioned lambda waves versus 46 (32.2%) of 143 prolonged EEG monitoring reports (P < 0.001). Multivariable comparison of prolonged EEG monitorings and standard EEGs disclosed that recordings performed in rooms with a TV (odds ratio, 20.6; 95% confidence interval, 4.8-88.0) and normal EEGs (odds ratio, 3.03; 95% confidence interval, 1.5-6.25) were independently associated with lambda waves. In the prolonged EEG monitoring group, all recordings with lambda waves also had positive occipital sharp transients of sleep. CONCLUSIONS: Watching TV likely represents a powerful and previously unrecognized stimulus for lambda waves. Furthermore, this study confirms the benign nature of this EEG variant and its strong association with positive occipital sharp transients of sleep.

Cellular and genetic mechanisms involved in the generation of protective and pathogenic immune responses in human Chagas disease

Perhaps one of the most intriguing aspects of human Chagas disease is the complex network of events that underlie the generation of protective versus pathogenic immune responses during the chronic phase of the disease. While most individuals do not develop patent disease, a large percentage may develop severe forms that eventually lead to death. Although many efforts have been devoted to deciphering these mechanisms, there is still much to be learned before we can fully understand the pathogenesis of Chagas disease. It is clear that the host's immune response is decisive in this process. While characteristics of the parasite influence the immune response, it is becoming evident that the host genetic background plays a fundamental role in the establishment of pathogenic versus protective responses. The involvement of three complex organisms, host, parasite and vector, is certainly one of the key aspects that calls for multidisciplinary approaches towards the understanding of Chagas disease. We believe that now, one hundred years after the discovery of Chagas disease, it is imperative to continue with highly interactive research in order to elucidate the immune response associated with disease evolution, which will be essential in designing prophylactic or therapeutic interventions.

Natural evidence for rapid abiogenic hydrothermal generation of CH4

Although recent hydrothermal experiments imply that abiogenic methane (CH4) generation from hydrothermal reduction of CO2 can occur, evidence from natural systems was still lacking. Based on the chemical and isotopic equilibrium signatures of low-temperature fumarolic gas discharges, we are able to provide hard evidence for its natural occurrence, namely in three subduction-related bi-phase hydrothermal systems of the Mediterranean, whose temperatures range from 260 to 470 degrees C. The attainment of equilibrium and the time spans of recent volcanic dormancy allowed us to calculate minimum rates for chemical and isotopic equilibration. These are significantly higher than those previously reported and might be due to the presence of a saturated water vapor phase in the investigated systems. The fact that nature provides conditions enabling relatively fast production of hydrocarbons from CO2 strongly supports the concerns that were recently raised from laboratory experiments. These address the use of the carbon isotope composition of reduced carbon in Archean sediments as a tracer of early life and the occurrence of CH4 on extraterrestrial planets as a bioindicator. In view of the potential role of abiogenic CH4 as a precursor of life, we also present an estimate of abiogenic hydrothermal CH4 fluxes throughout the Archean. It is not expected that these fluxes exceeded 80 Mt/yr during the past 4.0 Ga. This, however, would have been enough to facilitate HCN production on the prebiotic Earth. (C) 2007 Elsevier Ltd. All rights reserved.

Fingermark detection based on the in situ growth of luminescent nanoparticles: towards a new generation of multimetal deposition

The in situ deposition of zinc oxide on gold nanoparticles in aqueous solution has been here successfully applied in the field of fingermark detection on various non-porous surfaces. In this article, we present the improvement of the multimetal deposition, an existing technique limited up to now to non-luminescent results, by obtaining luminescent fingermarks with very good contrast and details. This is seen as a major improvement in the field in terms of selectivity and sensitivity of detection, especially on black surfaces.

Efficient generation of human alloantigen-specific CD4+ regulatory T cells from naive precursors by CD40-activated B cells.

CD4(+)CD25(+)Foxp3(+) regulatory T cells (Treg) play an important role in the induction and maintenance of immune tolerance. Although adoptive transfer of bulk populations of Treg can prevent or treat T cell-mediated inflammatory diseases and transplant allograft rejection in animal models, optimal Treg immunotherapy in humans would ideally use antigen-specific rather than polyclonal Treg for greater specificity of regulation and avoidance of general suppression. However, no robust approaches have been reported for the generation of human antigen-specific Treg at a practical scale for clinical use. Here, we report a simple and cost-effective novel method to rapidly induce and expand large numbers of functional human alloantigen-specific Treg from antigenically naive precursors in vitro using allogeneic nontransformed B cells as stimulators. By this approach naive CD4(+)CD25(-) T cells could be expanded 8-fold into alloantigen-specific Treg after 3 weeks of culture without any exogenous cytokines. The induced alloantigen-specific Treg were CD45RO(+)CCR7(-) memory cells, and had a CD4(high), CD25(+), Foxp3(+), and CD62L (L-selectin)(+) phenotype. Although these CD4(high)CD25(+)Foxp3(+) alloantigen-specific Treg had no cytotoxic capacity, their suppressive function was cell-cell contact dependent and partially relied on cytotoxic T lymphocyte antigen-4 expression. This approach may accelerate the clinical application of Treg-based immunotherapy in transplantation and autoimmune diseases.

Generation of cell polarity in plants links endocytosis, auxin distribution and cell fate decisions.

Dynamically polarized membrane proteins define different cell boundaries and have an important role in intercellular communication-a vital feature of multicellular development. Efflux carriers for the signalling molecule auxin from the PIN family are landmarks of cell polarity in plants and have a crucial involvement in auxin distribution-dependent development including embryo patterning, organogenesis and tropisms. Polar PIN localization determines the direction of intercellular auxin flow, yet the mechanisms generating PIN polarity remain unclear. Here we identify an endocytosis-dependent mechanism of PIN polarity generation and analyse its developmental implications. Real-time PIN tracking showed that after synthesis, PINs are initially delivered to the plasma membrane in a non-polar manner and their polarity is established by subsequent endocytic recycling. Interference with PIN endocytosis either by auxin or by manipulation of the Arabidopsis Rab5 GTPase pathway prevents PIN polarization. Failure of PIN polarization transiently alters asymmetric auxin distribution during embryogenesis and increases the local auxin response in apical embryo regions. This results in ectopic expression of auxin pathway-associated root-forming master regulators in embryonic leaves and promotes homeotic transformation of leaves to roots. Our results indicate a two-step mechanism for the generation of PIN polar localization and the essential role of endocytosis in this process. It also highlights the link between endocytosis-dependent polarity of individual cells and auxin distribution-dependent cell fate establishment for multicellular patterning.

A rapid assay for the coupled cell free generation of oxylipins

We developed a rapid and simple assay for the coupled in vitro synthesis of oxylipins using free unsaturated fatty acids as substrates. Reactions were catalysed with extracts expressed from living plant tissues. Preliminary experiments involving the cell free transformation of fatty acid hydroperoxides revealed that storage or pretreatment of the plant extract rapidly altered its capacity to catalyse the generation of oxidised fatty acid derivatives. This could reflect changes in oxylipin generation that might take place in situ in damaged plant cells during herbivory. All subsequent experiments were performed without dilution, titration or any other modification of the plant extract prior to its addition to the assay system. The assays were used to study, for the first time, tissue-specific differences in fatty acid transformation to divinyl ethers. Root tissues from tomato efficiently catalysed the formation of corneleic and colnelenic acids from linoleic acid and linolenic acids, respectively, whereas leaf, hypocotyl and cotyledon extracts did not promote the formation of these compounds. We observed the efficient generation of 9-oxo-nonanoic acid from the substrate linolenic acid and speculate that this aldehyde could arise either from the action of hydroperoxide lyase on 9-hydroperoxylinolenic acid or by a novel route involving cleavage of colnelenic acid which was also present among the products of the reaction. A potential role of divinyl ethers as substrates for the generation of toxic aldehydes is discussed

The generation and re-generation of social capital and enterprises in multi-stakeholders social cooperative enterprises: a system dynamic approach

Theories on social capital and on social entrepreneurship have mainly highlighted the attitude of social capital to generate enterprises and to foster good relations between third sector organizations and the public sector. This paper considers the social capital in a specific third sector enterprise; here, multi-stakeholder social cooperatives are seen, at the same time, as social capital results, creators and incubators. In the particular enterprises that identify themselves as community social enterprises, social capital, both as organizational and relational capital, is fundamental: SCEs arise from but also produce and disseminate social capital. This paper aims to improve the building of relational social capital and the refining of helpful relations drawn from other arenas, where they were created and from where they are sometimes transferred to other realities, where their role is carried on further (often working in non-profit, horizontally and vertically arranged groups, where they share resources and relations). To represent this perspective, we use a qualitative system dynamic approach in which social capital is measured using proxies. Cooperation of volunteers, customers, community leaders and third sector local organizations is fundamental to establish trust relations between public local authorities and cooperatives. These relations help the latter to maintain long-term contracts with local authorities as providers of social services and enable them to add innovation to their services, by developing experiences and management models and maintaining an interchange with civil servants regarding these matters. The long-term relations and the organizational relations linking SCEs and public organizations help to create and to renovate social capital. Thus, multi-stakeholder cooperatives originated via social capital developed in third sector organizations produce new social capital within the cooperatives themselves and between different cooperatives (entrepreneurial components of the third sector) and the public sector. In their entrepreneurial life, cooperatives have to contrast the "working drift," as a result of which only workers remain as members of the cooperative, while other stakeholders leave the organization. Those who are not workers in the cooperative are (stake)holders with "weak ties," who are nevertheless fundamental in making a worker's cooperative an authentic social multi-stakeholders cooperative. To maintain multi-stakeholder governance and the relations with third sector and civil society, social cooperatives have to reinforce participation and dialogue with civil society through ongoing efforts to include people that provide social proposals. We try to represent these processes in a system dynamic model applied to local cooperatives, measuring the social capital created by the social cooperative through proxies, such as number of volunteers and strong cooperation with public institutions. Using a reverse-engineering approach, we can individuate the determinants of the creation of social capital and thereby give support to governance that creates social capital.

MHC class II/ESO tetramer-based generation of in vitro primed anti-tumor T-helper lines for adoptive cell therapy of cancer.

Generation of tumor-antigen specific CD4(+) T-helper (T(H)) lines through in vitro priming is of interest for adoptive cell therapy of cancer, but the development of this approach has been limited by the lack of appropriate tools to identify and isolate low frequency tumor antigen-specific CD4(+) T cells. Here, we have used recently developed MHC class II/peptide tetramers incorporating an immunodominant peptide from NY-ESO-1 (ESO), a tumor antigen frequently expressed in different human solid and hematologic cancers, to implement an in vitro priming platform allowing the generation of ESO-specific T(H) lines. We isolated phenotypically defined CD4(+) T-cell subpopulations from circulating lymphocytes of DR52b(+) healthy donors by flow cytometry cell sorting and stimulated them in vitro with peptide ESO(119-143), autologous APC and IL-2. We assessed the frequency of ESO-specific cells in the cultures by staining with DR52b/ESO(119-143) tetramers (ESO-tetramers) and TCR repertoire of ESO-tetramer(+) cells by co-staining with TCR variable β chain (BV) specific antibodies. We isolated ESO-tetramer(+) cells by flow cytometry cell sorting and expanded them with PHA, APC and IL-2 to generate ESO-specific T(H) lines. We characterized the lines for antigen recognition, by stimulation with ESO peptide or recombinant protein, cytokine production, by intracellular staining using specific antibodies, and alloreactivity, by stimulation with allo-APC. Using this approach, we could consistently generate ESO-tetramer(+) T(H) lines from conventional CD4(+)CD25(-) naïve and central memory populations, but not from effector memory populations or CD4(+)CD25(+) Treg. In vitro primed T(H) lines recognized ESO with affinities comparable to ESO-tetramer(+) cells from patients immunized with an ESO vaccine and used a similar TCR repertoire. In this study, using MHC class II/ESO tetramers, we have implemented an in vitro priming platform allowing the generation of ESO-monospecific polyclonal T(H) lines from non-immune individuals. This is an approach that is of potential interest for adoptive cell therapy of patients bearing ESO-expressing cancers.

Automatic generation of active coordinates for quantum dynamics calculations: application to the dynamics of benzene photochemistry

A new practical method to generate a subspace of active coordinates for quantum dynamics calculations is presented. These reduced coordinates are obtained as the normal modes of an analytical quadratic representation of the energy difference between excited and ground states within the complete active space self-consistent field method. At the Franck-Condon point, the largest negative eigenvalues of this Hessian correspond to the photoactive modes: those that reduce the energy difference and lead to the conical intersection; eigenvalues close to 0 correspond to bath modes, while modes with large positive eigenvalues are photoinactive vibrations, which increase the energy difference. The efficacy of quantum dynamics run in the subspace of the photoactive modes is illustrated with the photochemistry of benzene, where theoretical simulations are designed to assist optimal control experiments

Generation of mouse-induced pluripotent stem cells by transient expression of a single nonviral polycistronic vector

Induced pluripotent stem (iPS) cells have generated keen interestdue to their potential use in regenerative medicine. They havebeen obtained from various cell types of both mice and humans byexogenous delivery of different combinations of Oct4, Sox2, Klf4,c-Myc, Nanog, and Lin28. The delivery of these transcription factorshas mostly entailed the use of integrating viral vectors (retrovirusesor lentiviruses), carrying the risk of both insertional mutagenesisand oncogenesis due to misexpression of these exogenousfactors. Therefore, obtaining iPS cells that do not carry integratedtransgene sequences is an important prerequisite for their eventualtherapeutic use. Here we report the generation of iPS cell linesfrom mouse embryonic fibroblasts with no evidence of integrationof the reprogramming vector in their genome, achieved by nucleofectionof a polycistronic construct coexpressing Oct4, Sox2, Klf4,and c-Myc

A protocol describing the genetic correction of somatic human cells and subsequent generation of IPS cell

The generation of patient-specific induced pluripotent stem cells (iPSCPSCPSCs) offers unprecedented opportunities for modeling and treating human disease. In combination with gene therapy, the iPSCPSCPSC technology can be used to generate disease-free progenitor cells of potential interest for autologous cell therapy. We explain a protocol for the reproducible generation of genetically corrected iPSCPSCPSCs starting from the skin biopsies of Fanconi anemia patients using retroviral transduction with OCT4, SOX2 and KLF4. Before reprogramming, the fibroblasts and/or keratinocytes of the patients are genetically corrected with lentiviruses expressing FANCA. The same approach may be used for other diseases susceptible to gene therapy correction. Genetically corrected, characterized lines of patient-specific iPSCPSCPSCs can be obtained in 4–5 months.

Generation of induced pluripotent stem cells from human cord blood cells with only two factors:OCT4 and SOX2

Induced pluripotent stem cells (iPSC ) provide an invaluable resource for regenerative medicine as they allow the generationof patient-specific progenitors with potential value for cell therapy. However, in many instances, an off-the-shelf approach isdesirable, such as for cell therapy of acute conditions or when the patient’s somatic cells are altered as a consequence of a chronicdisease or aging. Cord blood (CB) stem cells appear ideally suited for this purpose as they are young cells expected to carryminimal somatic mutations and possess the immunological immaturity of newborn cells; additionally, several hundred thousandimmunotyped CB units are readily available through a worldwide network of CB banks. Here we present a detailed protocol for thederivation of CB stem cells and how they can be reprogrammed to pluripotency by retroviral transduction with only two factors(OCT 4 and SO X2) in 2 weeks and without the need for additional chemical compounds.