Room temperature electron spin relaxation in GaInNAs multiple quantum wells at 1.3 mu m

The authors report a direct measurement of electron spin relaxation in GaInNAs semiconductor multiple quantum wells at room temperature. Multiple quantum wells of widths 5.8, 7, and 8 nm exhibiting excitonic absorption around 1.3 mu m have been studied. Spin relaxation times were found to increase with well width in the range of 77-133 ps. The spin relaxation time dependence on first electron confinement energy suggests the Elliot-Yafet mechanism [A. Tackeuchi , Physica B 272, 318 (1999)] as the dominant relaxation process. (c) 2006 American Institute of Physics.</p

roadmap to vasculitis a rheumatological treasure hunt part iv management of vasculitis

Abstract At the stop sign we read the "red flags" and made up our mind and followed one of the road signs pointing to secondary, primary or fake vasculitis. Since then we have steadily followed the road map and passed the first (patient history and physical exam), second and third milestones (laboratory, imaging and pathology studies in the primary care and specialized centres) and have finally reached our destination at the fourth milestone (Part IV) on the road map review to vasculitis. In the management of these syndromes, Birmingham Vasculitis Activity Score (BVAS) and Vasculitis Damage Index (VDI) are not widely used in the routine clinical work, but they are introduced as the idea behind them is really valid. The backbone of the medical therapy is the use of immunosuppressive doses of prednisone (1 mg/kg/day). In some life-threatening and non-responsive vasculitides this is combined with cyclophosphamide 2–4 mg/kg/day or 0.5–1.0 g/m 2 i.v. every 2–4 weeks (European Vasculitis group uses 15 mg/kg every 2–3 weeks), often at 3–6 months substituted either with methotrexate or azathioprine. In contrast, i.v. immunoglobulins are to be used in Kawasaki's syndrome; cyclosporine, dapsone or colchicine in Behcet's disease; calcium channel blockers in BACNS; and NSAID in small vessel disease; whereas plasmapheresis or immunoadsorption are added to the therapy in Goodpasture's syndrome. Particular attention is drawn to the treatment of the triggers, use of biologicals and new cytostatic drugs and anti-metabolites, prevention of thromboembolic complications with anti-platelet drugs as well as to odd and orphan entities. A short travelogue ends our odyssey as the last sign on our roadmap

roadmap to vasculitis a rheumatological treasure hunt part ii classification features of individual vasculitides and differential diagnosis against pseudovasculitis

Abstract Since the triggering factors causing primary vasculitides are by definition not (yet) known, we have to classify them to clinical syndromes based on the size, site, type and effect of the blood vessel involvement. ACR classification criteria and Chapel Hill nomenclature are useful tools to familiarize with the primary vasculitides, although a lot of criticism has been voiced in the literature indicating that they only represent the best available consensus. The present text takes advantage of the recent developments such as introduction of the anti-neutrophilic cytoplasmic auto (ANCA) antibodies, and divides the vasculitides to those affecting typically the large, medium and small arteries or only small blood vessels. In addition, some vasculitides, which are still difficult to place to the vasculitis map, like Burger's disease, Goodpasture's syndrome, primary angiitin of the central nervous system (PACNS) and panniculitis, are dealt with. As it is a long and winding road, attention has to be paid to the clinical details to follow the road sign to "pseudovasculitis", when that is the right way to go. They represent a bunch of non-vasculitic conditions, which lead to structural or vasospastic impairment of the blood flow, bleeding or thromboembolism and hyperviscosity. These imitators have to some extent, similar clinical symptoms and signs as well as laboratory and radiological findings to those found in true systemic vasculitides. This also emphasizes the importance of internal medicine as the intellectual (albeit not necessarily organizational) home of rheumatology and rheumatologists as we deal with conditions like atherosclerosis, antiphospholipid antibody syndrome, infectious endocarditic, myxoma of the heart and cholesterol embolism

roadmap to vasculitis a rheumatological treasure hunt

Abstract Vasculitis is characterized by inflammation of the wall of blood vessels. It involves immunologically mediated responses to usually unknown antigens, which result in vessel wall damage. Weakening of the vessel wall can lead to aneurysms, dissections or bleeding and narrowing of the lumen (caused by vasculitis per se and complicating thrombosis and embolization) resulting in ischemic damage and necrosis of the affected end organs and tissues. The first part of this four-part review describes the red flags and stop signs, which could help the busy doctor to stop and to start to think of the possibility of vasculitis. This is particularly important as many of these syndromes are life-threatening and hence their diagnostics can be compared to "a rheumatologic treasure hunt" as the treasured life of the patient is often at stake. Everything starts with simple measures, namely taking the patient history and conducting a complete physical examination. This is often enough for the identification of triggering factors as causes as well as targets of therapy in secondary vasculitides. They are often also enough for the right diagnosis, which only needs to be confirmed, perhaps by specialists, with more elaborate and expensive methodology

Nothing to Sneeze at: Histamine and Histamine Receptors in Oral Carcinogenesis

Oral squamous cell carcinoma (OSCC), the most common oral malignancy, shows an increasing rate of incidence worldwide. In spite of the recent advances in cancer research, OSCC therapy continues to have unfavourable outcomes, and thus patient’s prognosis remains relatively poor. Current research has been devoted to identifying novel therapeutic targets also in the tumour microenvironment (TME). Histamine and its G-protein coupled receptors (H1R-H4R) play vital roles in multiple cancer-associated processes in TME, where histamine is mainly produced by mast cells. However, oral epithelial cells were recently shown to produce low concentrations of histamine in autocrine and paracrine modes. These findings, together with the discovery of the high-affinity histamine H4 receptor, have led to a massive increase in our understanding of histamine functions. This minireview aims to summarize the most recent findings regarding histamine and its receptors and their involvement in oral carcinogenesis—from oral potentially malignant disorders (OPMDs) to invasive OSCC. Importantly, histamine receptors are differentially expressed in OPMDs and OSCC. Furthermore, H1R and H4R are associated with clinicopathological characteristics of OSCC patients, suggesting a role in prognosis. Due to the enormous success of histamine-based medications, histamine receptors may also represent promising and viable drug targets in oral cancer.Peer reviewe

Acidic cysteine endoproteinase cathepsin K in the degeneration of the superficial articular hyaline cartilage in osteoarthritis

Peer reviewe

Role of nitric oxide in Sjogren's syndrome

Peer reviewe