Release of interleukin-12 in experimental Escherichia coli septic shock in baboons: relation to plasma levels of interleukin-10 and interferon- gamma

Interleukin (IL)-12 is thought to be a key factor for the induction of interferon gamma (IFN-gamma), a cytokine essential for the lethal effects of endotoxin. We report here on the release of the nonfunctional subunit of IL-12, p40, as well as biologically active heterodimeric IL-12, p70, after administration of a lethal (n = 5) or sublethal (n = 8) dose of live Escherichia coli to baboons. Remarkably, on lethal challenge, peak levels of p40 were observed at 3 hours that were about twofold lower than those elicited after sublethal challenge (2,813 +/- 515 pg/mL v 4,972 +/- 732 pg/mL, P < .05). This disparity was also observed, although to a lesser extent, for IL-12 p70 antigen, of which maximum levels of 91 +/- 47 pg/mL and 151 +/- 41 pg/mL were measured 6 hours after a lethal or sublethal dose of E coli, respectively. Circulating p70 antigen correlated with IL-12 biologic activity (r = 0.869; P < .001). When comparing lethal to sublethal conditions, lower peak levels of IL-12 on lethal E coli sharply contrasted with higher levels of other proinflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, IL-1beta, IL-6, and IL-8 observed in these animals. Lower IL-12 concentrations in the lethal group may have resulted in part from the enhanced production of IL-10, a known inhibitor of IL-12 synthesis in vitro, as peak levels of this cytokine 3 hours postchallenge inversely correlated with peak levels of IL-12, in particular p40 (r = -0.802; P < .01). Contrary to what might be expected if IFN-gamma were solely induced by IL-12, lethally challenged baboons generated threefold more IFN-gamma at 6 hours than those receiving a sublethal dose (P < .05). Moreover, higher levels of IFN- gamma were associated with lower p40/p70 ratios, suggesting that, in agreement with observations in vitro, IFN-gamma may have preferentially upregulated the release of p70 over p40. These data show that IL-12 is released in experimental septic shock in nonhuman primates and suggest that IL-10 and IFN-gamma are involved in the regulation of this release. Furthermore, this study indicates that the systemic release of IL-12 might be essential, but is not likely sufficient, to promote lethal production of IFN-gamma in sepsis.     

Cytokine targeting in osteoarthritis

Cytokines are involved in osteoarthritis (OA) at several levels. They are involved in primary cartilage damage, but also in synovial activation that is observed in osteoarthritic joints. From in vitro studies and animal models for OA, several cytokines have been identified that are potential targets for OA therapy. Two promising targets are the destructive cytokine Interleukin-1 (IL-1) and the anabolic growth factor transforming growth factor (TGF)beta and these will be discussed in more detail. Inhibition of IL-1 has been proven to result in amelioration of osteoarthritis-like pathology in animal models and the role of IL-1 is substantiated in studies in IL-1 deficient mice. In contrast, application of the anabolic growth factor TGFbeta may provide an alternative approach to promote cartilage integrity and repair. TGFbeta is a potent stimulator of chondrocyte matrix production, and therefore has a potency to repair already damaged cartilage. However, TGFbeta induces tissue fibrosis and osteophytes at the joint margins and can only be applied to promote cartilage repair when these side effects can be blocked. This appears possible with concomitant, compartmentalized application of selective inhibitors of TGFbeta in soft tissues, using local gene therapy with inhibitory Smad 6 and 7. Since OA is often limited to a few joints, local gene therapy may provide a suitable way to treat OA patients. Depending on the phenotype of a particular OA patient, e.g. with or without marked synovial activation, treatment may be focused mainly on suppression of catabolism or stimulation of anabolism, but combination therapy seems most warranted.     

Extraforaminal ligament attachments of the thoracic spinal nerves in humans

An anatomical study of the extraforaminal attachments of the thoracic spinal nerves was performed using human spinal columns. The objectives of the study are to identify and describe the existence of ligamentous structures at each thoracic level that attach spinal nerves to structures at the extraforaminal region. During the last 120 years, several mechanisms have been described to protect the spinal nerve against traction. All the described structures were located inside the spinal canal proximal to the intervertebral foramen. Ligaments with a comparable function just outside the intervertebral foramen are mentioned ephemerally. No studies are available about ligamentous attachments of thoracic spinal nerves to the spine. Five embalmed human thoracic spines (Th2–Th11) were dissected. Bilaterally, the extraforaminal region was dissected to describe and measure anatomical structures and their relationships with the thoracic spinal nerves. Histology was done at the sites of attachment of the ligaments to the nerves and along the ligaments. The thoracic spinal nerves are attached to the transverse process of the vertebrae cranial and caudal to the intervertebral foramen. The ligaments consist mainly of collagenous fibers. In conclusion, at the thoracic level, direct ligamentous connections exist between extraforaminal thoracic spinal nerves and nearby structures. They may serve as a protective mechanism against traction and compression of the nerves by positioning the nerve in the intervertebral foramen.     

Below-elbow cast sufficient for treatment of minimally displaced metaphyseal both-bone fractures of the distal forearm in children: long-term results of a randomized controlled multicenter trial

Background and purpose — We have previously shown that children with minimally displaced metaphyseal both-bone forearm fractures, who were treated with a below-elbow cast (BEC) instead of an above-elbow cast (AEC), experienced more comfort, less interference in daily activities, and similar functional outcomes at 7 months’ follow-up (FU). This study evaluates outcomes at 7 years’ follow-up.Patients and methods — A secondary analysis was performed of the 7 years’ follow-up data from our RCT. Primary outcome was loss of forearm rotation compared with the contralateral forearm. Secondary outcomes were patient-reported outcome measures (PROMs) consisting of the ABILHAND-kids and the DASH questionnaire, grip strength, radiological assessment, and cosmetic appearance.Results — The mean length of FU was 7.3 years (5.9–8.7). Of the initial 66 children who were included in the RCT, 51 children were evaluated at long-term FU. Loss of forearm rotation and secondary outcomes were similar in the 2 treatment groups.Interpretation — We suggest that children with minimally displaced metaphyseal both-bone forearm fractures should be treated with a below-elbow cast.

Long-term follow-up of children with forearm fractures is scarce but essential, because the remodeling capacity by growth can behave as a friend or an enemy. Previous studies with short-term follow-up shown that metaphyseal both-bone fractures of the distal forearm could safely be treated with a below-elbow cast (BEC) (Bohm et al. 2006, Webb et al. 2006, Paneru et al. 2010, Hendrickx et al. 2011, Colaris et al. 2012, Van Den Bekerom et al. 2012). Our previous randomized multicenter controlled trial compared BEC with above-elbow cast (AEC) for the treatment of minimally displaced metaphyseal both-bone fractures of the distal forearm in children. This RCT concluded that children with minimally displaced metaphyseal both-bone fractures of the distal forearm should be treated with a below-elbow cast (Colaris et al. 2012). We now report the long-term 7-year follow-up of these 2 treatment groups regarding loss of forearm rotation, patient-reported outcomes measures (ABILHAND-kids questionnaire and DASH questionnaire (Hudak et al. 1996, Penta et al. 1998, Arnould et al. 2004), grip strength, radiological assessment, and cosmetic appearance (Bohm et al. 2006, Paneru et al. 2010, Hendrickx et al. 2011, Colaris et al. 2012, Van Den et al. 2012)     

Involvement of the Wnt signaling pathway in experimental and human osteoarthritis: Prominent role of Wnt‐induced signaling protein 1

Objective

Wnt signaling pathway proteins are involved in embryonic development of cartilage and bone, and, interestingly, developmental processes appear to be recapitulated in osteoarthritic (OA) cartilage. The present study was undertaken to characterize the expression pattern of Wnt and Fz genes during experimental OA and to determine the function of selected genes in experimental and human OA.

Methods

Longitudinal expression analysis was performed in 2 models of OA. Levels of messenger RNA for genes from the Wnt/β‐catenin pathway were determined in synovium and cartilage, and the results were validated using immunohistochemistry. Effects of selected genes were assessed in vitro using recombinant protein, and in vivo by adenoviral overexpression.

Results

Wnt‐induced signaling protein 1 (WISP‐1) expression was strongly increased in the synovium and cartilage of mice with experimental OA. Wnt‐16 and Wnt‐2B were also markedly up‐regulated during the course of disease. Interestingly, increased WISP‐1 expression was also found in human OA cartilage and synovium. Stimulation of macrophages and chondrocytes with recombinant WISP‐1 resulted in interleukin‐1–independent induction of several matrix metalloproteinases (MMPs) and aggrecanase. Adenoviral overexpression of WISP‐1 in murine knee joints induced MMP and aggrecanase expression and resulted in cartilage damage.

Conclusion

This study included a comprehensive characterization of Wnt and Frizzled gene expression in experimental and human OA articular joint tissue. The data demonstrate, for the first time, that WISP‐1 expression is a feature of experimental and human OA and that WISP‐1 regulates chondrocyte and macrophage MMP and aggrecanase expression and is capable of inducing articular cartilage damage in models of OA.

     

The unbroken power of psychiatry as seen through the eyes of Michel Foucault

Is the psychiatrist still a powerfulforce in society? Foucault, a 'historical philosopher' concerned with power relations, would have answered this question in the affirmative. Possibly, however, the psychiatrist's sovereign power is weaker than it was a century ago because some of the psychiatrist's tasks have been re-allocated. Some have been assigned to the growing number of specialist groups in the mental health service, others have been put in the hands of 'health managers' who form part of our country's growing bureaucracy and put a financial and economic burden on our health service. Nevertheless, the procedural power of psychiatrist has not been weakened; psychiatrists are able to deprive patients of their freedom, pronounce them unfit for work and reduce punishments and sentences for serious crime on the grounds of diminished responsibility. This procedural power is accentuated by the increasing influence of psychology in society. The power of psychiatric knowledge has shifted from an archaic to a demonstrative discourse about truth which is rooted in evidence-based medicine and which enhances the power of psychiatrists still further. This may also mean that the 19th century concept of hysteria is perpetuated in psychiatric practice in all kinds of modern clinical forms.     

Differentially methylated alleles in a distinct region of the human interleukin-1alpha promoter are associated with allele-specific expression of IL-1alpha in CD4+ T cells

Cytokine secretion profiles of activated T cells are critical for maintaining the immunologic balance between protection and tolerance. In mice, several cytokines have been reported to exhibit monoallelic expression. Previously, we found that the human interleukin-1 alpha (IL1A) gene exhibits a stable allele-specific expression pattern in CD4+ T-cell clones. We investigated whether DNA methylation is involved in the allele-specific expression of IL-1alpha. Here, we show that differential methylation of CpGs in the proximal promoter region is associated with allele-specific expression of IL-1alpha in CD4+ T cells. The differential methylation pattern is already observed in naive T cells. In keratinocytes, which constitutively produce IL-1alpha, the proximal promoter is hypomethylated. CpGs located further upstream and in intron 4 were almost all methylated, irrespective of expression. Treatment of nonexpressing cells and of T-cell clones with 5-aza-2'deoxycytidine induced IL-1alpha expression in the nonexpressing cells and induced expression of the formerly silent allele in T-cell clones. In addition, electrophoretic mobility shift assays showed that methylation of CpGs in the proximal promoter resulted in direct inhibition of binding of nuclear factor(s). Taken together, these results suggest that allele-specific expression of IL-1alpha in CD4+ cells is achieved, at least in part, by differential methylation of the promoter.