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Anti-beta-2 glycoprotein 1 (anti-β2GP1) is an antiphospholipid antibody found in patients with antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE). Its presence commonly is associated with thrombosis; however, the mechanisms of interaction of anti-β2GP1 antibodies and platelets remain unclear. We investigated the effects of APS and SLE patient-derived IgG fractions on collagen-mediated platelet aggregation and examined the binding of patient-derived IgG to platelets before and after activation by collagen. IgG fractions, 150, 200, 300 or 350 µg/ml, isolated from 11 patients with APS and SLE were incubated with two sets of platelet-rich plasma (PRP) in the incubation wells of an aggregometer. The first set was activated by collagen and the other set was incubated for an additional 10 min. All platelets were collected by centrifugation and fixed in cell blocks. We assessed binding of IgG to platelets using immunocytochemistry (ICC). Patient-derived IgG fractions did not affect collagen-induced platelet aggregation. ICC staining using anti-human IgG antibodies demonstrated that patient-derived IgG fractions had greater affinity for non-activated platelets than those activated by 0.75 µg/ml collagen. Patient-derived IgG fractions bound to the surface of platelets and potentially could be internalized by platelets. IgG fractions from APS and SLE patients may sensitize non-activated platelets, which could increase platelet reactivity and thrombotic risk in patients. We did not detect secondary effects of patient-derived IgG fractions. [ABSTRACT FROM AUTHOR]

Thrombosis is a frequent manifestation in patients with systemic lupus erythematosus (SLE), although precise mechanisms remain unclear. This study investigated whether the major physiological trigger of blood coagulation, the tissue factor (TF) pathway, was altered in SLE patients. Furthermore, we investigated potential associations between the TF pathway, the presence of antiphospholipid (APL) antibodies and other abnormalities present in SLE. A total of 101 participants (40 SLE patients and 61 age- and sex-matched controls) were recruited from Tasmania, Australia. Markers of the TF pathway, hypercoagulability, inflammation and endothelial cell damage were measured in plasma. Serum levels of APL antibodies (anti-cardiolipin antibodies [ACL], lupus anticoagulants [LAC], anti-beta2-glycoprotein-1 [anti-β2GP1] and anti-prothrombin antibodies) were also determined. Despite similar TF and TF pathway inhibitor (TFPI) total antigen levels, SLE patients had significantly increased levels of TFPI free antigen (patients vs controls; mean ± SD) (11.6 ± 0.9 ng/mL vs 6.4 ± 0.4 ng/mL; p < 0.001) but significantly reduced TFPI activity (0.66 ± 0.07 U/mL vs 1.22 ± 0.03 U/mL; p < 0.001), compared with healthy controls. Anti-TFPI activity, designated as the ability of isolated IgG fractions to inhibit TFPI activity in normal plasma, was detected in 19/40 (47.5%) of SLE patients and 3/40 (7.5%) of healthy controls. The significant reduction in TFPI activity in SLE patients reflects impaired functional control of the TF pathway. Moreover, SLE patients with a history of thrombosis demonstrated higher levels of TFPI activity compared with patients without a previous thrombotic event (0.97 ± 0.07 U/mL vs 0.53 ± 0.14 U/mL; p = 0.0026). Changes to the TF pathway were not associated with manifestations of SLE such as inflammation or endothelial cell damage. The results from this study suggest hypercoagulability in SLE may (in part) be due to reduced TFPI activity, a mechanism that appears to be independent of other abnormalities in SLE. [ABSTRACT FROM AUTHOR]

Introduction: African American men have the highest rates of prostate cancer of any racial group, but very little is known about the psychological functioning of African American men in response to prostate cancer diagnosis and treatment.Purpose: In this secondary analysis of a national trial testing a psychological intervention for prostate cancer patients, we report on the traumatic stress symptoms of African American and non-African American men.Methods: This analysis includes 317 men (African American: n = 30, 9%; non-African American: n = 287, 91%) who were enrolled in the intervention trial, which included 12 weeks of group psychotherapy and 24 months of follow-up. Using mixed model analysis, total score on the Impact of Events Scale (IES) and its Intrusion and Avoidance subscales were examined to determine mean differences in traumatic stress across all time points (0, 3, 6, 12, 18, and 24 months). In an additional analysis, relevant psychosocial, demographic, and clinical variables were added to the model.Results: Results showed significantly higher levels of traumatic stress for African American men compared to non-African American men in all models independently of the intervention arm, demographics, and relevant clinical variables. African Americans also had a consistently higher prevalence of clinically significant traumatic stress symptoms (defined as IES total score ≥ 27). These elevations remained across all time points over 24 months.Conclusions: This is the first study to show a racial disparity in traumatic stress specifically as an aspect of overall psychological adjustment to prostate cancer. Recommendations are made for appropriate assessment, referral, and treatment of psychological distress in this vulnerable population. [ABSTRACT FROM AUTHOR]

Background: Proponents of minimally invasive total knee arthroplasty claim that patellar eversion and anterior tibial translation during total knee arthroplasty have a deleterious effect on early patient rehabilitation and the early clinical outcome. Our purpose was to identify differences in knee preference and clinical outcome measures in a series of patients who had undergone bilateral total knee arthroplasty with each knee randomized to one of two different surgical approaches: patellar eversion and anterior tibial translation, or patellar subluxation and no tibial translation.Methods: The knees of forty patients were prospectively randomized to one of two treatment groups, patellar eversion or patellar subluxation, with each patient having one knee treated with each type of approach. Three patients were withdrawn, leaving a final study group of thirty-seven patients. The patients and physical therapists were blinded to the type of treatment. Clinical outcomes, including the Knee Society scores, range of motion, quadriceps strength as tested with a dynamometer, and the patient's preferred knee on the basis of pain, motion, and strength, were collected preoperatively and at six weeks, twelve weeks, and six months postoperatively and were analyzed.Results: At six weeks after the surgery, there were no significant differences between the two groups with regard to the range of motion, quadriceps strength, or Knee Society scores. With regard to the patient's knee preference at six weeks, the two knees were rated as being the same in terms of pain, whereas a higher percentage preferred the knee treated with eversion in terms of motion (43% compared with 35% who preferred the knee treated with subluxation) and strength (43% compared with 22%). The mean arc of motion in both groups was approximately 113 degrees. At twelve weeks and six months after the surgery, we found no significant differences between the treatment groups in terms of the range of motion, quadriceps strength, or Knee Society scores, and there was no difference with regard to the patient's knee preference.Conclusions: We found no significant differences between the two treatment groups (patellar eversion and anterior tibial translation compared with patellar subluxation and no tibial translation) at six weeks, twelve weeks, or six months after the surgery. We concluded that patellar eversion and anterior tibial translation appear to have no adverse effects on the range of motion, quadriceps strength, or patient's knee preference during the early postoperative recovery period after total knee arthroplasty. [ABSTRACT FROM AUTHOR]