Neutrophil gelatinase associated lipocalin (NGAL) is elevated in type 2 diabetics with carotid artery stenosis and reduced under metformin treatment.

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL), an acute phase protein released by neutrophils, has been described as biomarker of inflammatory states. Type 2 diabetes mellitus (T2DM) is characterized by increased inflammation and an elevated risk for embolization of carotid artery stenosis (CAS). We aimed to explore the role of NGAL systemically and in plaques of diabetics undergoing carotid endarterectomy. Moreover, the potential anti-inflammatory effect of metformin on NGAL was addressed in diabetics. METHODS: Serum NGAL and matrix metalloproteinase (MMP)-9/NGAL levels were measured in 136 patients (67 with T2DM vs. 69 non-diabetics) by specific ELISA. Endarterectomy samples were graded histologically according to the American Heart Association´s classification. NGAL mRNA expression was detected using RealTime-PCR in carotid endarterectomy specimens. RESULTS: Serum NGAL [median 107.4 ng/ml (quartiles: 75.2-145.0) vs. 64.4 (50.4 -81.3), p < 0.0001] and MMP-9/NGAL [41.5 ng/ml (20.8-63.9) vs. 27.6 (16.0-42.4), p = 0.017] were significantly elevated in diabetics compared to non-diabetics, as were leukocytes, neutrophils, C-reactive protein and fibrinogen (all p < 0.05). In patients with symptomatic and asymptomatic CAS diabetics had higher NGAL levels compared to non-diabetics [128.8 ng/ml (100.8-195.6) vs. 64.8 (48.9-82.2] and [101.6 ng/ml (70.1-125.3) vs. 63.8 (51.0-81.3), respectively, both p < 0.0001]. Presence of T2DM and type VI plaques (with surface defect, hemorrhage or thrombus) had a profound impact on NGAL levels (both p < 0.01) in multiple linear regression analysis. NGAL mRNA was detectable in 95% of analyzed carotid artery lesions of diabetics compared to 5% of non-diabetics (p < 0.0001). Accordingly, cerebral embolization was more frequent in diabetics (52.2% vs. 29%, p = 0.006). Metformin treatment was associated with decreased NGAL [60.7 ng/ml (51.9-69.2) vs. 121.7 (103.7-169.9), p < 0.0001] and MMP-9/NGAL [20.8 ng/ml (12.1-26.5) vs. 53.7 (27.4-73.4), p = 0.007] in diabetics and reduced leukocyte infiltration in carotid lesions of diabetics. CONCLUSIONS: Higher NGAL levels in serum and plaques are associated with T2DM in patients with CAS. Metformin significantly reduced the inflammatory burden including NGAL in diabetics. Early treatment of these patients may be recommended, as elevated NGAL levels were linked with vulnerable plaques prone for embolization.

Interleukin levels and their potential association with venous thromboembolism and survival in cancer patients.

Cytokines have been found to be elevated in cancer patients and have been associated with worse prognosis in single tumour entities. We investigated the association of eight different cytokines with venous thromboembolism (VTE) and prognosis in cancer patients. The Vienna Cancer and Thrombosis Study (CATS), a prospective study, includes patients with newly diagnosed tumour or disease progression. Patients with an overt infection are excluded. Study end-points are VTE, death, loss to follow-up or study completion. Interleukin (IL) serum levels were measured using the xMAP technology developed by Luminex. Among 726 included patients, no associations between IL levels and VTE were found, with the exception of a trend for IL-1ß and IL-6 in pancreatic cancer. Elevated levels of IL-6 [as continuous variable per double increase hazard ratio (HR) = 1·07, 95% confidence interval (CI) = 1·027-1·114, P = 0·001, IL-8 (HR = 1·12, 95% CI = 1·062-1·170, P < 0·001) and IL-11 (HR = 1·37, 95% CI = 1·103-1·709, P = 0·005] were associated with worse survival. In subgroup analyses based on tumour type, colon carcinoma patients, who had higher IL-6 levels, showed a shorter survival (HR = 2·405, 95% CI = 1·252-4·618, P = 0·008). A significant association of elevated IL-10 levels with a decrease in survival (HR = 1·824, 95% CI = 1·098-3·031, P = 0·020) was seen among patients with lung cancer. No correlation between VTE and IL levels was found, but higher IL-6, IL-8 and IL-11 levels were associated with worse survival in cancer patients. Further, elevated IL-6 levels might be a prognostic marker in colorectal cancer and elevated IL-10 levels in lung cancer patients.

The association of the Thr715Pro P-selectin genotype with levels of P-selectin in platelet concentrates.

BACKGROUND AND OBJECTIVES: P-selectin is stored in the alpha granules of platelets and in the Weibel Palade bodies of endothelial cells; upon activation, it is translocated to the cell surface and released into the plasma in soluble form. One variant of the P-selectin gene, the Thr715Pro polymorphism, is strongly associated with the plasma levels of soluble P-selectin. In platelet concentrates soluble P-selectin can be regarded mainly platelet derived. MATERIALS AND METHODS: The relation of the genotype with soluble P-selectin, platelet expressed P-selectin and the sum of all forms of P-selectin - comprising soluble P-selectin, platelet surface P-selectin and P-selectin from the alpha granules - was assessed in fresh whole blood and in apheresis platelets suspended in 35% plasma/65% SSP+ obtained from 89 platelet donors. RESULTS: Levels of total P-selectin were genotype associated (P = 0·025); likewise, in fresh whole blood there was an association of soluble P-selectin with genotype (P = 0·02). In platelets suspended in additive solution, however, levels of the storage-associated or TRAP-6 agonist induced increase of platelets' P-selectin were not associated with the genotype. A correlation between levels of soluble P-selectin and surface expression of P-selectin was observed on day 3 of storage in Thr715Thr individuals (P < 0·0001), but not in heterozygotes (Thr715Pro, P = 0·2). CONCLUSION: The donors' genotype has only little influence on levels of soluble P-selectin in apheresis platelets suspended in 35% plasma/65% SSP+.

Comparison of the effects of albumin 5%, hydroxyethyl starch 130/0.4 6%, and Ringer's lactate on blood loss and coagulation after cardiac surgery.

BACKGROUND: Infusion of 5% human albumin (HA) and 6% hydroxyethyl starch 130/0.4 (HES) during cardiac surgery expand circulating volume to a greater extent than crystalloids and would be suitable for a restrictive fluid therapy regimen. However, HA and HES may affect blood coagulation and could contribute to increased transfusion requirements. METHODS: We randomly assigned 240 patients undergoing elective cardiac surgery to receive up to 50 ml kg(-1) day(-1) of either HA, HES, or Ringer's lactate (RL) as the main infusion fluid perioperatively. Study solutions were supplied in identical bottles dressed in opaque covers. The primary outcome was chest tube drainage over 24 h. Blood transfusions, thromboelastometry variables, perioperative fluid balance, renal function, mortality, intensive care unit, and hospital stay were also assessed. RESULTS: The median cumulative blood loss was not different between the groups (HA: 835, HES: 700, and RL: 670 ml). However, 35% of RL patients required blood products, compared with 62% (HA) and 64% (HES group; P=0.0003). Significantly, more study solution had to be administered in the RL group compared with the colloid groups. Total perioperative fluid balance was least positive in the HA group [6.2 (2.5) litre] compared with the HES [7.4 (3.0) litre] and RL [8.3 (2.8) litre] groups (P<0.0001). Both colloids affected clot formation and clot strength and caused slight increases in serum creatinine. CONCLUSIONS: Despite equal blood loss from chest drains, both colloids interfered with blood coagulation and produced greater haemodilution, which was associated with more transfusion of blood products compared with crystalloid use only.

The discriminatory capacity of BMD measurements by DXA and dual X-ray and laser (DXL) at the calcaneus including clinical risk factors for detecting patients with vertebral fractures.

UNLABELLED: Osteoporotic fracture risk depends on bone mineral density (BMD) and clinical risk factors (CRF). Five hundred and eighty-eight untreated female and male outpatient subjects were evaluated, 160 with vertebral fractures. BMD was measured both by using calcaneal dual X-ray and laser (DXL) and dual-energy X-ray absorptiometry (DXA), and CRF were evaluated. Detection frequencies for different BMD methods with or without CRF are presented. INTRODUCTION: Osteoporotic fracture risk depends on bone mineral density and clinical risk factors. DXA of the spine/hip is considered a gold standard for BMD assessment, but due to degenerative conditions, particularly among the older population, assessment of BMD at the lumbar spine has been shown to be of limited significance. Portable calcaneal dual X-ray technology and laser can be an easily obtainable alternative. METHODS: Vertebral fractures were evaluated in a baseline analysis of 588 females and males (median age 64.4, range 17.6-93.1 years), comparing BMD measurements by using DXL and DXA and CRF with/without BMD. One hundred and sixty subjects had radiological verified vertebral fractures. Area under receiver-operating characteristic curves (AUROCC) and univariate and multiple logistic regressions were calculated. RESULTS: AUROCC for detection of vertebral fractures was comparable for DXL at calcaneus and DXA at femoral neck (DXL 0.665 and DXA 0.670). Odds ratio for prevalent vertebral fracture was generally weak for DXA femoral neck (0.613) and DXL (0.521). Univariate logistic regression among CRF without BMD revealed age, prevalent fragility fracture, and body mass index significantly associated with prevalent vertebral fracture (AUROCC = 0.805). Combining BMD and CRF, a prognostic improvement in case of DXA at femoral neck (AUROCC 0.869, p = 0.02), DXL at calcaneus (AUROCC 0.869, p = 0.059), and DXA at total hip (AUROCC 0.861, p = 0.06) was observed. CONCLUSIONS: DXL was similarly sensitive compared with DXA for identification of subjects with vertebral fragility fractures, and combination of CRF with BMD by DXL or DXA further increased the discriminatory capacity for detection of patients susceptible to vertebral fracture.

Formant frequency discrimination with a fine structure sound coding strategy for cochlear implants.

Recent sound coding strategies for cochlear implants (CI) have focused on the transmission of temporal fine structure to the CI recipient. To date, knowledge about the effects of fine structure coding in electrical hearing is poorly charactarized. The aim of this study was to examine whether the presence of temporal fine structure coding affects how the CI recipient perceives sound. This was done by comparing two sound coding strategies with different temporal fine structure coverage in a longitudinal cross-over setting. The more recent FS4 coding strategy provides fine structure coding on typically four apical stimulation channels compared to FSP with usually one or two fine structure channels. 34 adult CI patients with a minimum CI experience of one year were included. All subjects were fitted according to clinical routine and used both coding strategies for three months in a randomized sequence. Formant frequency discrimination thresholds (FFDT) were measured to assess the ability to resolve timbre information. Further outcome measures included a monosyllables test in quiet and the speech reception threshold of an adaptive matrix sentence test in noise (Oldenburger sentence test). In addition, the subjective sound quality was assessed using visual analogue scales and a sound quality questionnaire after each three months period. The extended fine structure range of FS4 yields FFDT similar to FSP for formants occurring in the frequency range only covered by FS4. There is a significant interaction (p = 0.048) between the extent of fine structure coverage in FSP and the improvement in FFDT in favour of FS4 for these stimuli. FS4 Speech perception in noise and quiet was similar with both coding strategies. Sound quality was rated heterogeneously showing that both strategies represent valuable options for CI fitting to allow for best possible individual optimization.

Evaluation of stroke volume variation obtained by arterial pulse contour analysis to predict fluid responsiveness intraoperatively.

BACKGROUND: Fluid management guided by oesophageal Doppler monitor has been reported to improve perioperative outcome. Stroke volume variation (SVV) is considered a reliable clinical predictor of fluid responsiveness. Consequently, the aim of the present trial was to evaluate the accuracy of SVV determined by arterial pulse contour (APCO) analysis, using the FloTrac/Vigileo system, to predict fluid responsiveness as measured by the oesophageal Doppler. METHODS: Patients undergoing major abdominal surgery received intraoperative fluid management guided by oesophageal Doppler monitoring. Fluid boluses of 250 ml each were administered in case of a decrease in corrected flow time (FTc) to <350 ms. Patients were connected to a monitoring device, obtaining SVV by APCO. Haemodynamic variables were recorded before and after fluid bolus application. Fluid responsiveness was defined as an increase in stroke volume index >10%. The ability of SVV to predict fluid responsiveness was assessed by calculation of the area under the receiver operating characteristic (ROC) curve. RESULTS: Twenty patients received 67 fluid boluses. Fifty-two of the 67 fluid boluses administered resulted in fluid responsiveness. SVV achieved an area under the ROC curve of 0.512 [confidence interval (CI) 0.32-0.70]. A cut-off point for fluid responsiveness was found for SVV > or =8.5% (sensitivity: 77%; specificity: 43%; positive predictive value: 84%; and negative predictive value: 33%). CONCLUSIONS: This prospective, interventional observer-blinded study demonstrates that SVV obtained by APCO, using the FloTrac/Vigileo system, is not a reliable predictor of fluid responsiveness in the setting of major abdominal surgery.

Effects of clopidogrel with or without aspirin on the generation of extracellular vesicles in the microcirculation and in venous blood: A randomized placebo controlled trial.

BACKGROUND: Dual-antiplatelet therapy (DAPT) is a standard strategy in acute coronary heart disease; however, it confers a considerable bleeding risk. Single-antiplatelet therapy (SAPT) inhibits haemostatic system activation ex vivo to a similar extent as DAPT. Extracellular vesicles (EV) are procoagulant and contribute to haemostatic system activation. We aimed to investigate the effect of DAPT compared with SAPT on EV. METHODS: In a randomized, double-blind, placebo-controlled trial, 44 healthy volunteers received DAPT (clopidogrel + aspirin) or SAPT (clopidogrel + placebo) for 7 days. Blood was obtained from a standardized microvascular injury and through venipuncture at baseline (BL) and at 2 h, 24 h, and 8 days after treatment initiation. The number, origin, and surface expression of EV were assessed using flow cytometry. Data are given as median (quartiles). Non-parametric tests were used to evaluate the short-term (BL vs 2 h) and long-term differences (2 h to 8 days), as well as the differences between treatment groups. RESULTS: There was no difference either in the short-term effects on the number (×103 mL-1) of EV in microvascular blood between DAPT [BL: 1433 (653; 3184) vs 2 h: 862 (545; 2026), p = 0.39] and SAPT [(BL: 614 (552; 1402) vs 2 h: 1079 (781; 1538), p = 0.75)] or in the long-term effects. DAPT and SAPT did not exhibit differential short-term effects on the number and proportion (36% and 27% vs 55% and 36%) of platelet-derived EV. DAPT and SAPT resulted in a significant short-term increase in phosphatidylserine expression in microvascular blood. The effects of DAPT and SAPT on EV in venous blood were similar to those in microvascular blood. CONCLUSION: DAPT and SAPT have comparable effects on the amount, origin, and surface characteristics of EV.

Pelvic reconstruction following resection of malignant bone tumours using a stemmed acetabular pedestal cup.

AIMS: Pelvic reconstruction after the resection of a tumour around the acetabulum is a challenging procedure due to the complex anatomy and biomechanics. Several pelvic endoprostheses have been introduced, but the rates of complication remain high. Our aim was to review the use of a stemmed acetabular pedestal cup in the management of these patients. PATIENTS AND METHODS: The study involved 48 patients who underwent periacetabular reconstruction using a stemmed pedestal cup (Schoellner cup; Zimmer Biomet Inc., Warsaw, Indiana) between 2000 and 2013. The indications for treatment included a primary bone tumour in 27 patients and metastatic disease in 21 patients. The mean age of the patients at the time of surgery was 52 years (16 to 83). RESULTS: At a median follow-up of 6.6 years (95% confidence interval 4.6 to 8.2), local control was achieved in all patients; 19 patients had died (16 of disease). Complications occurred in 19 patients (40%), of which deep infection was the most common, affecting eight patients (17%). Seven patients (15%) had a dislocation of the hip. Aseptic loosening was found in three patients (6%). Two (4%) underwent hindquarter amputation for non-oncological reasons. The risk of revision, with death being treated as a competing event, was 28% at one year, 39% at five years and 48% at ten years post-operatively. The mean Musculoskeletal Tumour Society Score at final follow-up was 71% (27% to 93%). CONCLUSION: This type of reconstruction is a satisfactory option for the treatment of patients with a periacetabular tumour. There remains, however, a high rate of complication, which may be reduced by future modifications of the device such as silver coating and tripolar articulation. Cite this article: Bone Joint J 2017;99-B:841-8.