Aneurysmal SubArachnoid Hemorrhage-Red Blood Cell Transfusion And Outcome (SAHaRA): a pilot randomised controlled trial protocol.

INTRODUCTION: Anaemia is common in aneurysmal subarachnoid haemorrhage (aSAH) and is a potential critical modifiable factor affecting secondary injury. Despite physiological evidence and management guidelines that support maintaining a higher haemoglobin level in patients with aSAH, current practice is one of a more restrictive approach to transfusion. The goal of this multicentre pilot trial is to determine the feasibility of successfully conducting a red blood cell (RBC) transfusion trial in adult patients with acute aSAH and anaemia (Hb ≤100 g/L), comparing a liberal transfusion strategy (Hb ≤100 g/L) with a restrictive strategy (Hb ≤80 g/L) on the combined rate of death and severe disability at 12 months. METHODS: Design This is a multicentre open-label randomised controlled pilot trial at 5 academic tertiary care centres. Population We are targeting adult aSAH patients within 14 days of their initial bleed and with anaemia (Hb ≤110 g/L). Randomisation Central computer-generated randomisation, stratified by centre, will be undertaken from the host centre. Randomisation into 1 of the 2 treatment arms will occur when the haemoglobin levels of eligible patients fall to ≤100 g/L. Intervention Patients will be randomly assigned to either a liberal (threshold: Hb ≤100 g/L) or a restrictive transfusion strategy (threshold: Hb ≤80 g/L). Outcome Primary: Centre randomisation rate over the study period. Secondary: (1) transfusion threshold adherence; (2) study RBC transfusion protocol adherence; and (3) outcome assessment including vital status at hospital discharge, modified Rankin Score at 6 and 12 months and Functional Independence Measure and EuroQOL Quality of Life Scale scores at 12 months. Outcome measures will be reported in aggregate. ETHICS AND DISSEMINATION: The study protocol has been approved by the host centre (OHSN-REB 20150433-01H). This study will determine the feasibility of conducting the large pragmatic RCT comparing 2 RBC transfusion strategies examining the effect of a liberal strategy on 12-month outcome following aSAH. TRIAL REGISTRATION NUMBER: NCT02483351; Pre-results.

Tumor necrosis factor, macrophage colony-stimulating factor, and interleukin 1 production within sponge matrix allografts.

Neither the presence nor the specific role of secretory cytokines in in vivo allograft rejection has been extensively studied. We quantitated the levels of colony-stimulating factors, tumor necrosis factor, and interleukin 1 within the rejecting allograft. BALB/c (H-2d) mice were implanted with polyurethane sponges containing either allogeneic C57BL/6 (H-2b) or syngeneic splenocytes, or splenocyte-free media. At various days postgrafting, the sponges were harvested, and the cells infiltrating the grafts were analyzed for specific antidonor cytolytic activity, while IL-1, TNF, and CSF levels were measured in the graft exudate fluid. Allogeneic grafts had significantly higher concentrations of CSF, TNF, and IL-1 than syngeneic of splenocyte-free grafts. A specific radioimmunoassay revealed that macrophage colony-stimulating factor (M-CSF) is the primary CSF produced in the grafts. Peak TNF levels preceded peak M-CSF and IL-1 levels, which coincided with the initial appearance of allospecific cytotoxic T lymphocytes. Maximal CTL activity was seen on day 13, when the levels of these cytokines had already begun to fall. Specific bioassays for multi-CSF (IL-3), granulocyte CSF, granulocyte-macrophage CSF, IL-2, and IL-4 failed to detect these cytokines in the sponge fluid at any time. We hypothesize that TNF, M-CSF, and IL-1 probably play regulatory roles in the immunologic events at the site of allograft challenge.

Toward a biochemical understanding of human intervertebral disc degeneration and herniation. Contributions of nitric oxide, interleukins, prostaglandin E2, and matrix metalloproteinases.

STUDY DESIGN: Normal and herniated human intervertebral disc specimens were cultured to study the effects of interleukin-1 beta on the production of nitric oxide, interleukin-6, prostaglandin E2, and matrix metalloproteinases. The effects of endogenously produced nitric oxide on the synthesis of other mediators also were studied. OBJECTIVES: To test the hypothesis that the cells of the intervertebral disc are metabolically active and are capable of responding to biochemical stimuli such as interleukin-1 beta in a manner that could engender degenerative changes. As part of this study, the authors also investigated some of the possible autocrine regulatory mechanisms that may operate during the biochemical responses of disc cells. SUMMARY OF BACKGROUND DATA: The authors previously showed, for the first time, that herniated cervical and lumbar disc specimens spontaneously produce increased amounts of nitric oxide, interleukin-6, prostaglandin E2, and certain matrix metalloproteinases. These results suggest that these biochemical agents are in some manner involved with degenerative processes in the intervertebral disc. This novel hypothesis merits further evaluation; the current communication reports the results of experiments designed to do so. METHODS: Fourteen normal, nondegenerated discs (control group) were obtained from seven patients undergoing anterior spinal surgery for trauma or lumbar scoliosis. Thirty-six herniated discs (18 lumbar and 18 cervical) were obtained from 30 patients undergoing surgery for persistent radiculopathy. The specimens were placed into tissue culture and incubated for 72 hours in the presence or absence of interleukin-1 beta and NG-monomethyl-L-arginine, and inhibitor of nitric oxide synthases, and the media were subsequently collected for biochemical analysis. Biochemical assays for matrix metalloproteinases, nitric oxide, interleukin-6, and prostaglandin E2 were performed. RESULTS: Normal, control disc specimens significantly increased their production of matrix metalloproteinases, nitric oxide, interleukin-6, and prostaglandin E2 in response to interleukin-1 beta. Herniated lumbar and cervical discs, which were spontaneously releasing increased levels of these biochemical agents, further increased their production of nitric oxide, interleukin-6, and prostaglandin E2 in response to interleukin-1 beta. Blocking the biosynthesis of nitric oxide in interleukin-1 beta-stimulated disc cells provoked a large increase in the production of interleukin-6. CONCLUSIONS: Cells of the intervertebral discs are biologically responsive and increase their production of matrix metalloproteinases, nitric oxide, interleukin-6, and prostaglandin E2 when stimulated by interleukin-1 beta. The effect is more dramatic in normal, nondegenerated discs where spontaneous synthesis of these mediators is low. Nevertheless, cells of the herniated degenerated discs where spontaneous production was high were still capable of further increasing their synthesis of several of these biochemical agents in response to interleukin-1 beta. Endogenously produced nitric oxide appears to have a strong inhibitory effect on the production of interleukin-6, which suggests that autocrine mechanisms play an important role in the regulation of disc cell metabolism.

The role of nitric oxide in proteoglycan turnover by bovine articular cartilage organ cultures.

Monolayer cultures of articular chondrocytes synthesize large amounts of nitric oxide (NO) following exposure to IL-1. The latter has antianabolic and procatabolic activities on these cells, but little is known about the role, if any, of NO in the integrated metabolic pathways of the chondrocyte. In the present study, the role of endogenously produced NO in both the synthesis and degradation of proteoglycans was investigated for the first time. Bovine articular cartilage slices exposed to 20 U/ml human rIL-1 beta (hrIL-1 beta) synthesized large amounts of NO for 1 to 2 days, after which production fell to a steady state level approximately 20% of the peak value for the remainder of the 14-day incubation. The NO synthase inhibitor, N-monomethyl L-arginine (L-NMA, 1 mM), blocked NO production and enhanced the acute catabolic effects of hrIL-1 beta in cartilage derived from both cartilage derived from both calves and adult animals. However, in late cultures, release of proteoglycans was reduced in the presence of L-NMA. The proteolytic activity in conditioned medium of these cultures (measured as caseinolytic activity) was enhanced by L-NMA; however, this inhibitor did not affect the rates of synthesis of proteoglycans. Although NO is widely assumed to be a mediator of cartilage catabolism, our data suggest that it may instead have an acute protective effect. Whether this effect is maintained chronically is less clear.

Articular chondrocytes synthesize nitric oxide in response to cytokines and lipopolysaccharide.

Although IL-1 is an important modulator of chondrocyte metabolism, the postreceptor events triggered by IL-1 remain obscure. The present study shows that IL-1 induces the biosynthesis of nitric oxide (.N = O) by articular chondrocytes. Synthesis of .N = O is also induced by LPS. Other inflammatory mediators such as IFN-gamma, fibroblast growth factor, and TNF-alpha fail to provoke the production of .N = O, but they increase the potency of IL-1. A combination of IL-1, LPS, and TNF-alpha was shown to induce maximal production of 355 +/- 51 nmol/10(6) cells/72 h of nitrite (NO2-), which was measured as a stable end-product of .N = O generation. The biosynthesis of .N = O requires an induction period of approximately 6 h and continues for at least 72 h. Inhibition of .N = O production with the competitive inhibitor NG-monomethyl-L-arginine (NMA) leads to a suppression of gelatinase and PGE2 synthesis by chondrocytes activated with IL-1 alone. In contrast, NMA enhances the synthesis of both gelatinase and PGE2 after activation with a combination of IL-1, LPS, and TNF-alpha. An increase of PGE2 synthesis from 42.0 +/- 21.0 to 174.0 +/- 33.5 ng/10(6) cells/72 h resulted from the addition of NMA when these stimulatory agents were combined. Exposure of IL-1 and fibroblast growth factor-stimulated chondrocytes to authentic, exogenous .N = O led to an increase of PGE2 synthesis from 5.6 +/- 1.7 of untreated cells to 15.8 +/- 6.8 ng/10(6) of .N = O treated cells within the 1st h. This was followed by a suppression of PGE2 synthesis within the next 2 h.