Annales des maladies vénériennes: Band XIV

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Interaction of the NO 3pπ (C 2Π) Rydberg state with RG (RG = Ne, Kr, and Xe): potential energy surfaces and spectroscopy

We present new potential energy surfaces for the interaction of NO(C 2Π) with each of Ne, Kr, and Xe. The potential energy surfaces have been calculated using second order Møller-Plesset perturbation theory, exploiting a procedure to converge the reference Hartree-Fock wavefunction for the excited states: the maximum overlap method. The bound rovibrational states obtained from the surfaces are used to simulate the electronic spectra and their appearance is in good agreement with available (2+1) REMPI spectra. We discuss the assignment and appearance of these spectra, comparing to that of NO-Ar

Impact of High-Molecular-Weight Hyaluronic Acid on Gene Expression in Rabbit Achilles Tenocytes In Vitro

(1) Background: Surgical tendon repair often leads to adhesion formation, leading to joint stiffness and a reduced range of motion. Tubular implants set around sutured tendons might help to reduce peritendinous adhesions. The lubricant hyaluronic acid (HA) is a viable option for optimizing such tubes with the goal of further enhancing the anti-adhesive effect. As the implant degrades over time and diffusion is presumed, the impact of HA on tendon cells is important to know. (2) Methods: A culture medium of rabbit Achilles tenocytes was supplemented with high-molecular-weight (HMW) HA and the growth curves of the cells were assessed. Additionally, after 3, 7 and 14 days, the gene expression of several markers was analyzed for matrix assembly, tendon differentiation, fibrosis, proliferation, matrix remodeling, pro-inflammation and resolution. (3) Results: The addition of HA decreased matrix marker genes, downregulated the fibrosis marker α-SMA for a short time and slightly increased the matrix-remodeling gene MMP-2. Of the pro-inflammatory marker genes, only IL-6 was significantly upregulated. IL-6 has to be kept in check, although IL-6 is also needed for a proper initial inflammation and efficient resolution. (4) Conclusions: The observed effects in vitro support the intended anti-adhesion effect and therefore, the use of HMW HA is promising as a biodegradable implant for tendon repair

Selective loss of myelin-associated glycoprotein from myelin correlates with anti-MAG antibody titre in demyelinating paraproteinaemic polyneuropathy

Summary The IgM monoclonal autoantibodies of patients with demyelinating paraproteinaemic polyneuropathy recognize a carbohydrate structure present on both myelin-associated glycoprotein (MAG) and protein zero (Po). These autoantibodies are sufficient to cause the disease but the mechanism of demyelination remains unclear. We have analysed nerve biopsies from eight patients with polyneuropathy and anti-MAG antibodies by quantitative immunohistochemistry and find a concordant pattern of reduced expression of myelin markers with the loss of myelinated fibres. We report here novel features of this disease, in particular a selective lack of detectable MAG in a large proportion of myelinated fibres containing Po, myelin basic protein (MBP) and periaxin. There is also an inverse correlation of the distribution of MAG in peripheral never myelin with the serum anti-MAG antibody titres but no correlation of these titres with the loss of myelinated fibres. Double immunofluorescence staining of paraproteinaemic polyneuropathy (PPN) nerves shows anti-MAG IgM deposited on the periphery of myelinated fibres associated with or lacking MAG staining. These data suggest that the binding of anti-MAG antibodies to MAG and/or other myelin component(s) results in MAG downregulation and may have an essential role in the molecular mechanisms leading to demyelination and partial regeneration in this diseas

Hyaluronic acid/PEO electrospun tube reduces tendon adhesion to levels comparable to native tendons - An in vitro and in vivo study

A major problem after tendon injury is adhesion formation to the surrounding tissue leading to a limited range of motion. A viable strategy to reduce adhesion extent is the use of physical barriers that limit the contact between the tendon and the adjacent tissue. The purpose of this study was to fabricate an electrospun bilayered tube of hyaluronic acid/polyethylene oxide (HA/PEO) and biodegradable DegraPol® (DP) to improve the anti-adhesive effect of the implant in a rabbit Achilles tendon full laceration model compared to a pure DP tube. Additionally, the attachment of rabbit tenocytes on pure DP and HA/PEO containing scaffolds was tested and Scanning Electron Microscopy, Fourier-transform Infrared Spectroscopy, Differential Scanning Calorimetry, Water Contact Angle measurements, and testing of mechanical properties were used to characterize the scaffolds. In vivo assessment after three weeks showed that the implant containing a second HA/PEO layer significantly reduced adhesion extent reaching levels comparable to native tendons, compared with a pure DP implant that reduced adhesion formation only by 20 %. Tenocytes were able to attach to and migrate into every scaffold, but cell number was reduced over two weeks. Implants containing HA/PEO showed better mechanical properties than pure DP tubes and with the ability to entirely reduce adhesion extent makes this implant a promising candidate for clinical application in tendon repair

Bioactive and Elastic Emulsion Electrospun DegraPol Tubes Delivering IGF-1 for Tendon Rupture Repair

Tendon injuries can result in two major drawbacks. Adhesions to the surrounding tissue may limit the range of motion, while fibrovascular scar formation can lead to poor biomechanical outcomes. Prosthetic devices may help to mitigate those problems. Emulsion electrospinning was used to develop a novel three-layer tube based on the polymer DegraPol (DP), with incorporated insulin-like growth factor-1 (IGF-1) in the middle layer. Scanning electron microscopy was utilized to assess the fiber diameter in IGF-1 containing pure DP meshes. Further characterization was performed with Fourier Transformed Infrared Spectroscopy, Differential Scanning Calorimetry, and water contact angle, as well as through the assessment of mechanical properties and release kinetics from ELISA, and the bioactivity of IGF-1 by qPCR of collagen I, ki67, and tenomodulin in rabbit Achilles tenocytes. The IGF-1-containing tubes exhibited a sustained release of the growth factor up to 4 days and showed bioactivity by significantly upregulated ki67 and tenomodulin gene expression. Moreover, they proved to be mechanically superior to pure DP tubes (significantly higher fracture strain, failure stress, and elastic modulus). The novel three-layer tubes intended to be applied over conventionally sutured tendons after a rupture may help accelerate the healing process. The release of IGF-1 stimulates proliferation and matrix synthesis of cells at the repair site. In addition, adhesion formation to surrounding tissue can be reduced due to the physical barrier

Biochemische Stigmata menschlicher Hautoberfläche im Alter

Peer Reviewe

Persistence of tumor-infiltrating CD8 T cells is tumor-dependent but antigen-independent

How tumor-infiltrating lymphocytes (TILs) that are tumor-specific but functionally tolerant persist in the antigen-expressing tumor tissue is largely unknown. We have previously developed a modified TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model where prostate cancer cells express the T-cell epitope SIYRYYGL (SIY) recognized by CD8 T cells expressing the 2C T-cell receptor (TCR) (referred to as TRP-SIY mice). In TRP-SIY mice, activated 2C T cells rapidly become tolerant following infiltration into the prostate tumor. In this study, we show that tolerant 2C T cells persist in the prostate tumor of TRP-SIY mice by proliferating slowly in a tumor-dependent, but antigen-, interleukin (IL)-7- and IL-15-independent manner. We also show that disappearance of 2C T cells from the lymphoid organs of TRP-SIY mice are due to antigen-induced T-cell contraction rather than altered trafficking or generalized T-cell depletion in the mice. Finally, we show that clonal T cells unreactive to SIY are equally capable of persisting in the prostate tumor. These findings suggest that while functional tolerance of TILs is induced by antigen, persistence of tolerant TILs in the tumor tissue is mediated by a novel mechanism: slow proliferation independent of antigen and homeostatic cytokines. These results also allow CD8 T-cell survival in the tumor environment to be compared with T-cell survival in chronic infection

From 'One Namibia, One Nation' towards 'Unity in Diversity? Shifting representations of culture and nationhood in Namibian Independence Day celebrations, 1990-2010

In 2010 Namibia celebrated its twentieth anniversary of independence from South African rule. The main celebrations in the country’s capital Windhoek became the stage for an impressively orchestrated demonstration of maturing nationhood, symbolically embracing postcolonial policy concepts such as ‘national reconciliation’, ‘unity’ and ‘diversity’. At the same time, nation building in post-apartheid Namibia is characterised by a high degree of social and political fragmentation that manifests itself in cultural and/or ethnic discourses of belonging. Taking the highly significant independence jubilee as our vantage point, we map out a shift of cultural representations of the nation in Independence Day celebrations since 1990, embodied by the two prominent slogans of ‘One Namibia, one Nation’ and ‘Unity in Diversity’. As we will argue, the difficult and at times highly fragile postcolonial disposition made it necessary for the SWAPO government, as primary nation builder, to accommodate the demands of regions and local communities in its policy frameworks. This negotiation of local identifications and national belonging in turn shaped, and continues to shape, the performative dimension of Independence Day celebrations in Namibia.Web of Scienc