Soluble TNF-R1, VEGF and other cytokines as markers of disease activity in systemic lupus erythematosus and lupus nephritis.

BACKGROUND: Current non-invasive methods of assessing disease activity in systemic lupus erythematosus (SLE) are of limited sensitivity and specificity. Testing includes acute phase markers, autoantibodies and complement levels. Although measurements of dsDNA antibodies and complement C3/C4 levels are routine, they remain of limited value. Improved blood and urine markers may help in early detection of flare, distinction between flare and chronic damage, and monitoring response to therapy. METHODS: A total of 87 patients with SLE were tested for the following cytokines in serum and urine: monocyte chemoattractant protein 1 (MCP-1), regulated upon activation, normal T cell expressed and secreted (RANTES), soluble tumour necrosis factor receptor 1 (sTNF-R1), interferon-inducible protein 10 (IP-10), monocyte inhibitory protein 1α (MIP-1α) and vascular endothelial growth factor (VEGF). Patients attending the Lupus Unit at St Thomas' Hospital, London, UK were divided into active lupus nephritis (LN), inactive LN and non-renal SLE groups based on their renal pathology and SLE disease activity index (SLEDAI). Cytokine testing was performed using the FIDIS multiplex bead assay. RESULTS: The mean level of serum sTNF-R1 was higher in the active LN group compared with both inactive LN and non-renal SLE groups ( p < 0.001). For urine measurements there were significant differences between active LN and non-renal SLE for VEGF ( p = 0.016), after statistical correction for multiple testing. Both urinary and serum sTNF-R1 and IP-10 levels correlated with SLEDAI scores ( p < 0.001), while serum VEGF correlated weakly with SLEDAI ( p = 0.025). The optimum combination for differentiating active from inactive LN patients was serum VEGF, sTNF-R1, MCP-1 and glomerular filtration rate plus urinary sTNF-R1 and protein-creatinine ratio. CONCLUSION: These results indicate that for active LN, sTNF-R1 could be a useful serum cytokine marker, with potential for VEGF in the urine. This study has confirmed the ability of the multiplex bead technique to detect cytokines in a good analytical range, including very low and high levels, in both serum and urine. Combining serum and urine markers provided additional sensitivity in distinguishing active from inactive LN.

Demonstration of intermediates between deoxy and carbonmonoxy hemoglobins by anaerobic high-performance liquid chromatography.

Intermediary ferrous hemoglobins (Hb) partially liganded with carbon monoxide (CO) were separated using an anaerobic high-performance liquid chromatography system equipped with a cation-exchange column at room temperature. Separations were achieved by applying various mixtures of oxy- and CO-Hb A to the column. The mobile phase contained 3 mM sodium dithionite which deoxygenated the oxy hemes but left the CO hemes intact, thereby producing hemoglobins bound with various numbers of CO molecules. Spectrophotometric analyses of the eluent showed that hemoglobins were eluted in the order of deoxy hemoglobin, Hb(CO), Hb(CO)2 Hb(CO)3 and Hb(CO)4.

Stability of asymmetrical hybrid hemoglobins. Determination by anaerobic high performance liquid chromatography.

Asymmetrical hybrid hemoglobins formed in mixtures of Hb A and Hb S, Hb F and Hb S, Hb S and Hb York(beta 146 His----Pro), and Hb A and Hb York were separated by high performance liquid chromatography on cation and anion exchange columns under anaerobic conditions. The ratio of the hybrid hemoglobin to the total mixture was consistently lower than that theoretically expected and decreased with longer elution times. The hybrid tetramer appears to be unstable even under anaerobic conditions and dissociates into alpha beta dimers. The time course of dissociation of the hybrid hemoglobins was determined by varying the separation programs and thus separating the hybrid hemoglobin at different elution times. The rate of the dissociation of the hybrid hemoglobins studied follows first order kinetics. The lines representing the time course of dissociation of hybrid hemoglobins were extrapolated to time 0 to determine the fraction of the hybrid hemoglobin in the mixture prior to separation. The values obtained for equimolar mixtures of Hb A and Hb S and Hb York and Hb S or Hb A were in agreement with the expected theoretical value (50%). In contrast, the value obtained for hybrid hemoglobin FS was slightly less (about 40%). AY and SY hybrid hemoglobins dissociated into dimers at a considerably faster rate than did AS and FS hybrid hemoglobins, possibly because of the mutation at the beta 146-position in hybrid hemoglobins containing alpha beta Y dimers. This mutation hinders the formation of salt bridges that normally stabilize the "T" quaternary conformation. Since such hybrid hemoglobins have a partial "R" conformation even when deoxygenated, their rate of dissociation to dimers is expected to increase.

Role of Na,K-ATPase in regulating acidification of early rat liver endocytic vesicles.

Endocytic vesicles are acidified by an electrogenic proton pump and a parallel chloride conductance; however, acidification might be decreased if electrogenic transporters, such as Na,K-ATPase, that increase vesicle interior-positive membrane potential were also present. We examined this issue in early rat liver endosomes using ion substitution and inhibitors to alter Na,K-ATPase activity. These early endosomes, labeled for 2 min with the fluorescent fluid-phase marker fluorescein isothiocyanate-dextran, consistently acidified faster than endosomes similarly labeled for a 10-min period. In chloride-free media initial rates of acidification of early endosomes were faster in K+ media than in Na+ medium, although addition of K+ to Na+ or Na+ to K+ media to allow Na,K-ATPase to function did not decrease the rate of acidification. In chloride-containing media, rates were the same regardless of cation composition. The Na,K-ATPase inhibitor vanadate was prepared from orthovanadate by several methods, all of which inhibited liver ATPase activity. Two hundred mumol/L vanadate, prepared Cl(-)-free, tended to decrease rates of acidification in all media tested and these effects achieved statistical significance in Cl(-)-free media containing 150 mmol/L K+ or mixtures of Na+ and K+ and in 145 mmol/L KCl/5 mmol/L NaCl medium. Vanadate stocks pH-adjusted with hydrogen chloride increased rates of acidification in sodium gluconate buffers, probably as a result of the effects of the included Cl-. Five mmol/L ouabain (loaded into vesicles by endocytosis) and the membrane-permeable analog strophanthidin (2 mmol/L) both markedly inhibited endosome acidification, regardless of buffer ion composition. Collectively, these results suggest that Na,K-ATPase does not regulate acidification of rat liver early endocytic vesicles, that vanadate may modestly inhibit endosome acidification and that ouabain at high concentrations may inhibit acidification from the vesicle interior face.

Acute cervical spine trauma: diagnostic performance of single-view versus three-view radiographic screening.

PURPOSE: To compare the diagnostic accuracy of single-view and three-view cervical spine radiographs in acute trauma. MATERIALS AND METHODS: Radiographs of 97 patients with acute cervical spine fractures were matched with those of 92 proved normal cases. Fourteen radiologists, including three senior attending radiologists each with more than 20 years of post-residency experience, four junior attending radiologists each with less than 5 years of practice experience, three senior radiology residents in their 3rd or 4th year of radiology residency, and four junior radiology residents at the end of their 1st year of radiology training, interpreted each case twice: once as a lateral-only study and again as a three-view study. Multireader-multicase receiver operating characteristic analysis was performed. Difficult cases were reviewed for trends in the errors. RESULTS: Eight of 14 readers detected fractures better with the three-view series. Among junior attending radiologists, the differences were statistically significant. Most improvements were in fractures of the dens and fractures and unilateral dislocations of the articular mass. Overall, sensitivity increased from 81.8% to 83.3%. The reliability of fracture classification improved. Less experienced readers performed better with the three-view series. CONCLUSION: A three-view screening radiographic series will allow most readers to detect a few more fractures than a single-view series. The improvements occur primarily in a subset of difficult-to-diagnose injuries.

Delayed leaks and fistulas after esophagogastrectomy: radiologic evaluation.

OBJECTIVE: Although breakdown of the esophagogastric anastomosis often occurs as a complication of esophagogastrectomy during the early postoperative period, it is not well recognized that anastomotic leaks and fistulas may occur during the late postoperative period (more than 1 month after surgery). The purpose of our study was to determine the radiologic appearance and clinical significance of these late leaks and fistulas. MATERIALS AND METHODS: A review of radiology records at our hospital from 1985 to 1991 revealed 37 patients who had upper gastrointestinal contrast studies an average of 13.3 months after esophagogastrectomy. RESULTS: Six patients (16%) had anastomotic leaks or fistulas that occurred during the late postoperative period. Four patients were asymptomatic; three had contrast studies that showed thin, blind-ending tracks extending from the anastomosis into the mediastinum, and the fourth had an esophagogastric fistula. One of the blind-ending tracks later progressed to a gastropleural fistula that was treated with antibiotics and drainage. One symptomatic patient had a gastropleural fistula, and the other had a gastrobronchial fistula. Both fistulas were surgically repaired. None of the leaks or fistulas was associated with recurrent tumor. CONCLUSION: Anastomotic leaks or fistulas may be detected on contrast studies obtained more than 1 month after esophagogastrectomy. Some leaks appear as blind-ending tracks that have no clinical significance, but others may be manifested by life-threatening gastropleural or gastrobronchial fistulas that necessitate surgical intervention.

Cholangiocarcinoma in patients with primary sclerosing cholangitis: a multicenter case-control study.

Patients with primary sclerosing cholangitis (PSC) have a significantly increased risk of developing cholangiocarcinoma (CCA). Risk factors for developing such a complication are not well defined. We conducted a multicenter, case-control study to determine the risk factors and possible predictors for CCA in patients with PSC. The demographic, clinical, and laboratory features of 26 PSC patients with CCA diagnosed over a 7-year period at eight academic centers were compared with 87 patients with PSC but no CCA (controls). There was no statistically significant difference in demographics, smoking, signs or symptoms or complications of PSC, indices of disease severity (Mayo Risk score or Child-Pugh score), frequency or duration or complications of inflammatory bowel disease (IBD), frequency of biliary surgery, or therapeutic endoscopy between the two groups. Alcohol consumption was significantly associated with CCA in patients with PSC (odds ratio: 2.95; 95% CI: 1.04-8.3). Serum carbohydrate antigen 19-9 (CA 19-9) was significantly higher in patients with CCA than those without (177 +/- 89 and 61 +/- 58 U/mL, respectively; P =.002). A serum CA 19-9 level > 100 U/mL had 75% sensitivity and 80% specificity in identifying PSC patients with CCA. In conclusion, alcohol consumption was a risk factor for having CCA in PSC patients. The indices of severity of liver disease were not associated with CCA in patients with PSC. Serum CA 19-9 appeared to have good ability to discriminate PSC patients with and without CCA.