Impact of Focal White Matter Damage on Localized Subcortical Gray Matter Atrophy in Multiple Sclerosis: A 5-Year Study.

BACKGROUND AND PURPOSE: It is unclear to what extent subcortical gray matter atrophy is a primary process as opposed to a result of focal white matter damage. Correlations between WM damage and atrophy of subcortical gray matter have been observed but may be partly attributable to indirect relationships between co-occurring processes arising from a common cause. Our aim was to cross-sectionally and longitudinally characterize the unique impact of focal WM damage on the atrophy of connected subcortical gray matter regions, beyond what is explainable by global disease progression. MATERIALS AND METHODS: One hundred seventy-six individuals with MS and 47 healthy controls underwent MR imaging at baseline and 5 years later. Atrophy and lesion-based disruption of connected WM tracts were evaluated for 14 subcortical gray matter regions. Hierarchic regressions were applied, predicting regional atrophy from focal WM disruption, controlling for age, sex, disease duration, whole-brain volume, and T2-lesion volume. RESULTS: When we controlled for whole-brain volume and T2-lesion volume, WM tract disruption explained little additional variance of subcortical gray matter atrophy and was a significant predictor for only 3 of 14 regions cross-sectionally (ΔR2 = 0.004) and 5 regions longitudinally (ΔR2 = 0.016). WM tract disruption was a significant predictor for even fewer regions when correcting for multiple comparisons. CONCLUSIONS: WM tract disruption accounts for a small percentage of atrophy in connected subcortical gray matter when controlling for overall disease burden and is not the primary driver in most cases.

Contact system revisited: an interface between inflammation, coagulation, and innate immunity.

The contact system is a plasma protease cascade initiated by factor XII (FXII) that activates the proinflammatory kallikrein-kinin system and the procoagulant intrinsic coagulation pathway. Anionic surfaces induce FXII zymogen activation to form proteolytically active FXIIa. Bacterial surfaces also have the ability to activate contact system proteins, indicating an important role for host defense using the cooperation of the inflammatory and coagulation pathways. Recent research has shown that inorganic polyphosphate found in platelets activates FXII in vivo and can induce coagulation in pathological thrombus formation. Experimental studies have shown that interference with FXII provides thromboprotection without a therapy-associated increase in bleeding, renewing interest in the FXIIa-driven intrinsic pathway of coagulation as a therapeutic target. This review summarizes how the contact system acts as the cross-road of inflammation, coagulation, and innate immunity.

Factor XII: a novel target for safe prevention of thrombosis and inflammation.

Plasma protein factor XII (FXII) activates the procoagulant and proinflammatory contact system that drives both the kallikrein-kinin system and the intrinsic pathway of coagulation. When zymogen FXII comes into contact with negatively charged surfaces, it auto-activates to the serine proteaseactivated FXII (FXIIa). Recently, various in vivo activators of FXII have been identified including heparin, misfolded protein aggregates, polyphosphate and nucleic acids. Murine models have established a central role of FXII in arterial and venous thrombosis. Despite its central function in thrombosis, deficiency in FXII does not impair haemostasis in animals and humans. In a preclinical cardiopulmonary bypass system in large animals, the FXIIa-blocking antibody 3F7 prevented thrombosis; however, in contrast to traditional anticoagulants, bleeding was not increased. In addition to its function in thrombosis, FXIIa initiates formation of the inflammatory mediator bradykinin. This mediator increases vascular leak, causes vasodilation, and induces chemotaxis with implications for septic, anaphylactic and allergic disease states. Therefore, targeting FXIIa appears to be a promising strategy for thromboprotection without associated bleeding risks but with anti-inflammatory properties.

Impaired DNase1-mediated degradation of neutrophil extracellular traps is associated with acute thrombotic microangiopathies.

BACKGROUND: Acute thrombotic microangiopathies (TMAs) are characterized by excessive microvascular thrombosis and are associated with markers of neutrophil extracellular traps (NETs) in plasma. NETs are composed of DNA fibers and promote thrombus formation through the activation of platelets and clotting factors. OBJECTIVE: The efficient removal of NETs may be required to prevent excessive thrombosis such as in TMAs. To test this hypothesis, we investigated whether TMAs are associated with a defect in the degradation of NETs. METHODS AND RESULTS: We show that NETs generated in vitro were efficiently degraded by plasma from healthy donors. However, NETs remained stable after exposure to plasma from TMA patients. The inability to degrade NETs was linked to a reduced DNase activity in TMA plasma. Plasma DNase1 was required for efficient NET degradation and TMA plasma showed decreased levels of this enzyme. Supplementation of TMA plasma with recombinant human DNase1 restored NET-degradation activity. CONCLUSIONS: Our data indicate that DNase1-mediated degradation of NETs is impaired in patients with TMAs. The role of plasma DNases in thrombosis is, as of yet, poorly understood. Reduced plasma DNase1 activity may cause the persistence of pro-thrombotic NETs and thus promote microvascular thrombosis in TMA patients.

Plasma DNA is Elevated in Patients with Deep Vein Thrombosis.

OBJECTIVE: To investigate if plasma DNA is elevated in patients with deep vein thrombosis (DVT) and to determine whether there is a correlation with other biomarkers of DVT. BACKGROUND: Leukocytes release DNA to form extracellular traps (ETs), which have recently been linked to experimental DVT. In baboons and mice, extracellular DNA co-localized with von Willebrand factor (VWF) in the thrombus and DNA appeared in circulation at the time of thrombus formation. ETs have not been associated with clinical DVT. SETTING: From December 2008 to August 2010, patients were screened through the University of Michigan Diagnostic Vascular Unit and were divided into three distinct groups: 1) the DVT positive group, consisting of patients who were symptomatic for DVT, which was confirmed by compression duplex ultrasound (n=47); 2) the DVT negative group, consisting of patients that present with swelling and leg pain but had a negative compression duplex ultrasound, (n=28); and 3) a control group of healthy non-pregnant volunteers without signs or symptoms of active or previous DVT (n=19). Patients were excluded if they were less than 18 years of age, unwillingness to consent, pregnant, on an anticoagulant therapy, or diagnosed with isolated calf vein thrombosis. METHODS: Blood was collected for circulating DNA, CRP, D-dimer, VWF activity, myeloperoxidase (MPO), ADAMTS13 and VWF. The Wells score for a patient's risk of DVT was assessed. The Receiver Operating Characteristic (ROC) curve was generated to determine the strength of the relationship between circulating DNA levels and the presence of DVT. A Spearman correlation was performed to determine the relationship between the DNA levels and the biomarkers and the Wells score. Additionally the ratio of ADAMTS13/VWF was assessed. RESULTS: Our results showed that circulating DNA (a surrogate marker for NETs) was significantly elevated in DVT patients, compared to both DVT negative patients (57.7±6.3 vs. 17.9±3.5ng/mL, P<.01) and controls (57.7±6.3 vs. 23.9±2.1ng/mL, P<.01). There was a strong positive correlation with CRP (P<.01), D-dimer (P<.01), VWF (P<.01), Wells score (P<.01) and myeloperoxidase (MPO) (P<.01), along with a strong negative correlation with ADAMTS13 (P<.01) and the ADAMTS13/VWF ratio. The logistic regression model showed a strong association between plasma DNA and the presence of DVT (ROC curve was determined to be 0.814). CONCLUSIONS: Plasma DNA is elevated in patients with deep vein thrombosis and correlates with biomarkers of DVT. A strong correlation between circulating DNA and MPO suggests that neutrophils may be a source of plasma DNA in patients with DVT.

Neutrophil extracellular traps promote deep vein thrombosis in mice.

BACKGROUND: Upon activation, neutrophils can release nuclear material known as neutrophil extracellular traps (NETs), which were initially described as a part of antimicrobial defense. Extracellular chromatin was recently reported to be prothrombotic in vitro and to accumulate in plasma and thrombi of baboons with experimental deep vein thrombosis (DVT). OBJECTIVE: To explore the source and role of extracellular chromatin in DVT. METHODS: We used an established murine model of DVT induced by flow restriction (stenosis) in the inferior vena cava (IVC). RESULTS: We demonstrate that the levels of extracellular DNA increase in plasma after 6 h IVC stenosis, compared with sham-operated mice. Immunohistochemical staining revealed the presence of Gr-1-positive neutrophils in both red (RBC-rich) and white (platelet-rich) parts of thrombi. Citrullinated histone H3 (CitH3), an element of NETs' structure, was present only in the red part of thrombi and was frequently associated with the Gr-1 antigen. Immunofluorescent staining of thrombi showed proximity of extracellular CitH3 and von Willebrand factor (VWF), a platelet adhesion molecule crucial for thrombus development in this model. Infusion of Deoxyribonuclease 1 (DNase 1) protected mice from DVT after 6 h and also 48 h IVC stenosis. Infusion of an unfractionated mixture of calf thymus histones increased plasma VWF and promoted DVT early after stenosis application. CONCLUSIONS: Extracellular chromatin, likely originating from neutrophils, is a structural part of a venous thrombus and both the DNA scaffold and histones appear to contribute to the pathogenesis of DVT in mice. NETs may provide new targets for DVT drug development.

Characterization of an in vivo model for the study of eyelash biology and trichomegaly: mouse eyelash morphology, development, growth cycle, and anagen prolongation by bimatoprost.

BACKGROUND: Hypertrichosis or alopecia of the eyelashes is associated with various diseases or may be drug induced. Although neither increase nor loss of eyelashes is life threatening, eyelash disorders can be psychologically disturbing. However, as control of eyelash growth and the underlying mechanisms of eyelash hypo- or hypertrichosis are largely obscure, available therapy is limited. OBJECTIVES: To improve this situation, we sought to establish a pragmatic, well-defined mouse model for the study and pharmacological investigation of eyelash follicle biology. METHODS: We took a morphometric approach to establish an eyelash model using female C57BL/6J mice by comparing with pelage hairs and highlighting the differences. We next applied a hypertrichosis-triggering agent and investigated its effect using the model. RESULTS: In eyelashes, a synchronized growth cycle was observed after morphogenesis but was completed earlier than pelage hairs. Exogen was strictly regulated and occurred in every cycle in the eyelash. Otherwise, general morphological features of mouse eyelashes (shafts, follicles, morphogenesis and growth cycle) were comparable with those of pelage hairs. The eyelash growth-stimulatory agent in humans, bimatoprost, significantly extended the duration of anagen, resulting in more and longer eyelashes, but there was no evidence of follicle neogenesis. CONCLUSIONS: This study shows that mouse eyelashes offer an excellent in vivo model for the quantitative and qualitative analysis of eyelash morphology, development, growth cycle, exogen and pharmacological modulation. This model will help to elucidate the unknown molecular controls of eyelash growth, and to develop novel drugs to treat eyelash disorders.

[Radical prostatectomy for men aged <56 years with prostate cancer. Cost of illness analysis]. / Radikale Prostatektomie bei Männern unter 56 Jahren mit Prostatakarzinom. Eine Krankheitskostenanalyse.

BACKGROUND: Prostate cancer is the most frequent malignant tumor in men; 10% of the patients are younger than 56 years at the time of diagnosis and are usually still working. The aim of this study was to evaluate the costs of the disease within the first 3 years from diagnosis. MATERIAL AND METHODS: A total of 200 patients (aged <56 years) after radical prostatectomy with curative intent were asked for their social status, professional training and job before and after radical prostatectomy, disablement, length of hospital stay, rehabilitation, early retirement, part-time retirement, retraining program, job-creating measures, and working conditions after radical prostatectomy. RESULTS: Of the 200 patients queried, 177 (88.5%) answered the questionnaire. Prior to the radical prostatectomy 163 patients were employed. They were off work for a mean time of 104.4 days, 83.4% of them received inpatient rehabilitation treatment after surgery, 121 (74.2%) regained full fitness for work, 9 (5.5%) retired on grounds of age, 21 (12.9%) had an early retirement because of the disease, and 12 (7.4%) became unemployed. Within the first 3 years after diagnosis, the following mean costs had to be paid: 465.79 by the patient, 6569.76 by the employer, 16,356.96 by the health insurance, 13,304.88 by the pension scheme, and 3912.57 by the employment office. CONCLUSION: The main costs in patients with prostate cancer and radical prostatectomy have to been paid by the health insurance scheme and the pension scheme; 74.3% of the patients regained full fitness for work. The time until reintegration into work was correlated to the extent of physical labor.

Intracellular calcium signaling by Jurkat T-lymphocytes exposed to a 60 Hz magnetic field.

To explore possible biochemical mechanisms whereby electromagnetic fields of around 0.1 mT might affect immune cells or developing cancer cells, we studied intracellular calcium signaling in the model system Jurkat E6-1 human T-leukemia cells during and following exposure to a 60 Hz magnetic field. Cells were labeled with the intracellular calcium-sensitive fluorescent dye Fluo-3, stimulated with a monoclonal antibody against the cell surface structure CD3 (associated with ligand-stimulated T-cell activation), and analyzed on a FACScan flow-cytometer for increases in intensity of emissions in the range of 515-545 nm. Cells were exposed during or before calcium signal-stimulation to 0.15 mTrms 60 Hz magnetic field. The total DC magnetic field of 78.2 microT was aligned 17.5 degrees off the vertical axis. Experiments used both cells cultured at optimal conditions at 37 degrees C and cells grown under suboptimal conditions of 24 degrees C, lowered external calcium, or lowered anti-CD3 concentration. These experiments demonstrate that intracellular signaling in Jurkat E6-1 was not affected by a 60 Hz magnetic field when culture and calcium signal-stimulation were optimal or suboptimal. These results do not exclude field-induced calcium-related effects further down the calcium signaling pathway, such as on calmodulin or other calcium-sensitive enzymes.