Influence of the centrifuge time of primary plasma tubes on routine coagulation testing.

Preparation of blood specimens is a major bottleneck in the laboratory throughput. Reliable strategies for reducing the time required for specimen processing without affecting quality should be acknowledged, especially for laboratories performing stat analyses. The present investigation was planned to establish a minimal suitable centrifuge time for primary samples collected for routine coagulation testing. Five sequential primary vacuum tubes containing 0.109 mol/l buffered trisodium citrate were collected from 10 volunteers and were immediately centrifuged on a conventional centrifuge at 1500 x g, at room temperature for 1, 2, 5, 10 and 15 min, respectively. Hematological and routine coagulation testing, including prothrombin time, activated partial thromboplastin time and fibrinogen, were performed. The centrifugation time was inversely associated with residual blood cell elements in plasma, especially platelets. Statistically significant variations from the reference 15-min centrifuge specimens were observed for fibrinogen in samples centrifuged for 5 min at most and for the activated partial thromboplastin time in samples centrifuged for 2 min at most. Meaningful biases related to the desirable bias were observed for fibrinogen in samples centrifuged for 2 min at most, and for the activated partial thromboplastin time in samples centrifuged for 1 min at most. According to our experimental conditions, a 5-10 min centrifuge time at 1500 x g may be suitable for primary tubes collected for routine coagulation testing.     

Factors affecting aseptic loosening of 4750 total hip arthroplasties: multivariate survival analysis

Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.     

Treatment of intervention sites of malignant pleural mesothelioma with radiotherapy: a Dutch-Belgian survey.

A survey was performed on the radiotherapy practice of malignant pleural mesothelioma in The Netherlands and Belgium in 2002. Thirty-eight out of 47 centres (81%) responded. Prophylactic radiotherapy to intervention sites is given by 32/38 (84%) centres, with all centres offering palliative radiation. For both prophylactic and palliative indications, all centres use hypo-fractionated schedules. The present study shows that in the radiotherapy community in The Netherlands and in Belgium, a de facto consensus exists that both prophylactic and symptomatic radiotherapy to intervention sites of malignant pleural mesothelioma are effective and that hypo-fractionated schedules should be used.     

TGF-β and IL-17 serum levels and specific immunotherapy

Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-β respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-β levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-β levels. There was moreover a significant relationship between TGF-β and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-β levels.     

Long-term Doppler echocardiographic evaluation of the right heart after major lung resections.

OBJECTIVE: The effects of major lung resections on cardiac function in the medium and long term have not been thoroughly evaluated. We have studied right heart function with serial Doppler echocardiography in patients undergoing lobectomy and pneumonectomy during 4 years of follow-up after surgery. METHODS: Thirty-six patients undergoing lobectomy and 15 receiving pneumonectomy were evaluated with one- and two-dimensional Doppler standard transthoracic echocardiography before surgery and 1 week, 3 months, 6 months, 1 year, and 4 years postoperatively. We have studied the right midventricular diastolic diameter (RVDD), the right ventricle free wall thickness, the tricuspid valve insufficiency (TVI) and regurgitation jet (TRJ), and the pulmonary artery systolic pressure (PASP). RESULTS: None of the patients died within the first postoperative year. After lobectomy there were no significant modifications of any variable at any time. RVDD progressively increased after pneumonectomy (26.5+/-2.2mm preoperatively vs 34.3+/-7.6 at 4 years; p<0.001). Four years after surgery all patients undergoing pneumonectomy had moderate TVI while only 55% of patients receiving lobectomy showed it (low grade in 50% and moderate in 5%). In this group of patients PASP increased from 26.1+/-2.6 mmHg preoperatively to 34.3+/-7.6 mmHg at 4 years (p<0.00001). CONCLUSIONS: Right ventricle modifications are clearly evident after pneumonectomy and even if they do not show a clear clinical impact they should not be neglected.     

Dipyridamole and RA-642 inhibit the production of superoxide anion and free radical damage to rat lens.

We studied the effects of dipyridamole and RA-642 on the production of superoxide anions and on oxygen radicals-induced lipid peroxidation in lens tissue homogenates from normal rats and rats given dipyridamole or RA-642 intraperitoneally. Superoxide production was evaluated by phenazine methosulphate (PMS)-induced nitroblue tetrazolium (NBT) reduction and lipid peroxidation by ferrous sulfate and ascorbic acid (FeAs)-induced malondialdehyde (MDA) production. Dipyridamole and RA-642 showed an inhibitory effect on both assays in the experiments with lens tissue homogenates from untreated or treated rats. The extent of inhibition, however, was significantly higher in pyrimidopyrimidinic-treated rats (range of inhibition at different times of incubation was 18% versus 23-57% for dipyridamole and 14% versus 73-80% for RA-642 in the assay of MDA production, and 10% versus 33-37% for dipyridamole and 2.5% versus 11-32% for RA-642 in the assay of NBT reduction). Concentrations of dipyridamole and RA-642 in lens tissue from treated animals could not be determined (less than 0.001 micrograms/mg of tissue). Although both compounds inhibited lipid peroxidation induced by oxygen free radicals, the mechanism of action might include the role of adenosine as a mediator.