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The temperature dependence of d.c. conductivity of poly(ethylene oxide) complexes with sodium iodide and the thiocyanates of sodium, potassium and ammonium has been investigated. In each case a transition to a lower activation energy at higher temperatures was observed. For the sodium complexes this transition occurs at ca 55°C which is well below the crystalline melting points at 200°C. For the potassium and ammonium complexes however, the transitions coincide with the melting points at ca 100 and 70°C respectively. It is proposed that at the transitions, thermal disintegration of complexes in the amorphous regions occurs. The complexes involve coordination of the cations to the ether oxygen atoms in the polymer backbone.

Recent developments in polymer electrolyte materials for lithium batteries are reviewed in this article. Four general classifications are recognized: (1) solvent-containing systems in which a liquid electrolyte solution either is fully miscible with a single-phase swollen polymer matrix (gel) or is a two-phase system in which “free” liquid occupies micropores within a swollen polymer network (hybrid), and conductivity (≥∼1 mS cm-1 at ambient temperature) is essentially independent of the polymer segmental motion (the thermal motion of segments of atoms along the backbone of a flexible polymer chain); (2) solvent-free, ion-coupled systems (typically polyether–Li salt complexes) in which both anions and cations are mobile within an amorphous, rubbery phase (conductivity ≤0.1 mS cm-1 at ambient temperature); (3) “single-ion” systems with anions fixed to the polymer backbone or systems with anion mobilities reduced by incorporation within larger molecules or by associations with the chain (conductivity ∼10-5 Scm-1 at ambient temperature); and (4) decoupled systems in which ionic mobility through channeled structures involves minimal local segmental displacements (conductivity 0.1–1 mS cm-1 at ambient temperature).

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Nitric oxide has been implicated as a mediator of inflammatory arthritis, and recent work has shown that pro-inflammatory cytokines stimulate NO production in vitro by activation of the inducible nitric oxide synthase (iNOS) pathway. In order to identify the cellular sources of NO production within the joint, we have used immunohistochemical techniques to study the distribution of iNOS in synovium and cartilage from normal and diseased joints. iNOS was most strongly expressed in the synovial lining layer, subsynovium, vascular smooth muscle and chondrocytes from patients with rheumatoid arthritis (RA). Analysis of serial sections, coupled with double immunofluorescent staining, showed that the CD68+ macrophages in the synovial lining layer and, to a lesser extent, fibroblasts were the predominant source of iNOS within synovium, whereas T cells, B cells and neutrophils were negative. A similar pattern of iNOS staining was seen in osteoarthritis, but fewer cells were iNOS positive and the intensity of staining, particularly in cartilage, was much weaker than in RA. In contrast, no evidence of iNOS was detected in non-inflammatory synovium or in cartilage derived from normal joints (fractured neck of femur). In conclusion, these data support the hypothesis that synovium and cartilage are important sources of increased NO production in patients with inflammatory arthritis. Localization of iNOS at these sites within the inflamed joint raises the possibility that increased local production of NO may contribute to the pathogenesis of inflammatory arthritis by increasing synovial blood flow and by modulating cellular function within synovium and articular cartilage.

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This study indicates that NO acts as a mediator of apoptosis in RA and suggests that NOS inhibitors reverse this process.

Purpose Gene signatures and Ki67 stratify the same breast tumor into opposing good/poor prognosis groups in approximately 20% of patients. Given this discrepancy, we hypothesized that the combination of a clinically relevant signature and IHC markers may provide more prognostic information than either classifier alone. Experimental Design We assessed Ki67 alone or combined with ER, PR and HER2 (forming IHC subtypes), and the research versions of the Genomic Grade Index, 70-gene, cell-cycle score, recurrence score (RS), and PAM50 signatures on matching TMA/whole tumor sections and microarray data in two Swedish breast cancer cohorts of 379 and 209 patients, with median follow-up of 12.4 and 12.5 years, respectively. First, we fit Cox proportional hazards models and used the change in likelihood ratio (Δ LR) to determine the additional prognostic information provided by signatures beyond that of (i) Ki67 and (ii) IHC subtypes. Second and uniquely, we then assessed whether signatures could compete well with pathology-based IHC classifiers by calculating the additional prognostic information of Ki67/IHC subtypes beyond signatures. Results In cohort 1, only RS and PAM50 provided additional prognostic information beyond Ki67 and IHC subtypes (Δ LR-χ2 Ki67: RS = 12.8, PAM50 = 20.7, IHC subtypes: RS = 12.9, PAM50 = 11.7). Conversely, IHC subtypes added prognostic information beyond all signatures except PAM50. Similar results were observed in cohort 2. Conclusions RS and PAM50 provided more prognostic information than the IHC subtypes in all breast cancer patients; however, the IHC subtypes did not add any prognostic information to PAM50.