Selective application of cervical spine radiography in alert victims of blunt trauma: a prospective study

Four hundred sixty-seven adult victims of blunt trauma undergoing cervical spine radiography (CSR) were prospectively studied to identify any clinical parameters which would aid in the selective application of CSR. Eight persons (1.7%), six of whom were alert and two who presented comatose, sustained cervical spine injuries. In this study, persons injured in falls demonstrated a statistically significant greater risk of cervical spine injury compared to those injured in motor vehicle accidents (p = 0.001). In alert trauma victims, a statistical correlation with cervical spine injury was noted for individuals who had complaints of neck discomfort (p = 0.028) and for patients who manifested tenderness to neck palpation (p = 0.000039). No cervical spine injury was noted in any alert, not intoxicated, neurologically intact patient who had no complaints of neck discomfort upon questioning or palpation. We conclude that alert trauma victims with no complaints of neck discomfort upon questioning and with no tenderness on neck palpation need not undergo CSR.     

5-HYDROXYTRYPTAMINE-INDUCED CONTRACTION OF THE MARMOSET AORTA IS MEDIATED BY A 5-HT1-LIKE RECEPTOR

1. 5-Hydroxytryptamine (5-HT) exerts both contractile and relaxant effects in the marmoset isolated aorta, actions that are unaffected by the 5-HT₂ antagonist ketanserin. The aim of the present study was to define the receptors mediating the contractile activity of 5-HT in the marmoset aorta.
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A₂ agonist U44069 in order to amplify the responses; or (ii) exposed to N ^ω-nitro- L -arginine (100 μmol/L) plus LY 53857 (0.1 μmol/L; a 5-HT₂ receptor antagonist shown previously to inhibit relaxation). The effect of 5-HT on adenosine 3',5'-cyclic monophosphate (cAMP) formation was also investigated.
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT_1D antagonist GR 127935; (iii) a contractile response to methysergide; (iv) a lack of effect of tropisetron, an antagonist of 5-HT₃ and 5-HT₄ receptors; and (v) inhibition of forskolin-stimulated cAMP formation by 5-HT (in the presence of LY 53857), indicative of negative coupling to adenylate cyclase.
4. The above effects fulfil the criteria for a 5-HT₁-like receptor. In view of the previous finding that this contractile response is insensitive to ketanserin, it is concluded that the contractile effects of 5-HT in the marmoset aorta are mediated exclusively by a 5-HT₁-like receptor.     

Intraocular production of a cytokine (CINC) responsible for neutrophil infiltration in endotoxin induced uveitis.

AIMS/BACKGROUND: The subcutaneous injection of bacterial endotoxin in Lewis rats produces an acute intraocular inflammation evolving over a 24 hour period. This endotoxin induced uveitis (EIU) is characterised by a biphasic protein exudation and a cellular infiltrate composed of macrophages and polymorphonuclear neutrophils (PMNs). This model was used to study the mechanism of cellular infiltration in ocular inflammation. METHODS: EIU was induced by a subcutaneous injection of lipopolysaccharide (LPS) (S typhimurium) at 350 micrograms/kg. The levels of cytokine induced neutrophil chemoattractant (CINC) were measured every 2 hours in the serum and in the aqueous humour by ELISA. The intraocular inflammation was quantified by protein measurement and leucocyte counting. RESULTS: The kinetics of CINC production in the systemic circulation showed a rapid rise, peaking 2 hours after LPS injection, followed by a progressive decline over the next 8 hours. In the eye, the CINC levels increased above the serum levels 10 hours after EIU induction corresponding to the time of cellular infiltration. When leucocyte entry in the eye was inhibited by 56% and 64% with an antiadhesion molecule antibody, there was only a slight reduction in the aqueous humour CINC levels of 9% and 16%, respectively, indicating that CINC was produced by ocular tissue cells. The specific effect of CINC in the eye was confirmed when a direct intraocular injection of 250 ng of purified CINC was followed by significant PMN infiltration, in the absence of protein exudation. CONCLUSION: The data indicate that the production of the CINC chemotactic factor by ocular tissue participates in the inflammatory reaction in EIU.     

The effect of cyclosporine on immunization with tetanus and keyhole limpet hemocyanin (KLH) in humans

Eleven patients with chronic uveitis treated with Cyclosporine were immunized with keyhole limpet hemocyanin (KLH) and tetanus toxoid. Delayed cutaneous hypersensitivity responses, lymphocyte blastogenic responses, and antibody production were compared with those of similarly immunized control individuals. A significant decrease in delayed cutaneous hypersensitivity (P<0.001 for KLH andP<0.01 for tetanus toxoid) was observed. No significant differences in blastogenic or antibody responses were noted. These findings demonstrate that the majority of the Cyclosporine-treated patients had intact T cell-dependent antigen responses as measured by both proliferative response and antibody production to primary and secondary antigenic challenges but that other immune functions such as delayed cutaneous hypersensitivity are affected by therapeutic doses of systemic Cyclosporine.