Viral myocarditis and coagulopathy: increased tissue factor expression and plasma thrombogenicity

We investigated the effects of viral infection on Tissue Factor (TF) expression and activity in mice within the myocardium to understand increased thrombosis during myocarditis. Mice were infected with coxsackie virus B3 (CVB3) and the hearts were collected at day 4, 8 and 28 post infection (p.i.). Myocardial TF expression and cellular activity as well as plasma activity were analyzed from CVB3 infected mice by Western blot, chromogenic Factor Xa generation assay, in situ staining for active TF and immunohistochemistry. In addition to TF expression, hemodynamic parameters were measured during the time course of infection. Furthermore, we analyzed myocardial tissues from patients with suspected inflammatory cardiomyopathy. TF protein expression was maximally 5-fold elevated 8 days p.i. in mice and remained increased on day 28 p.i. (P < 0.001 vs. non-infected controls). Alterations in TF expression were associated with fibrin deposits within the myocardium. The TF pathway inhibitor protein expression in the myocardium was not altered during myocarditis. Active cellular TF co-localized with CD3 positive cells and VCAM-1 positive endothelial cells in the myocardium. The TF expression was positively correlated with the amount of infiltrating CD3 and Mac3 positive cells (Spearman-Rho ρ = 0.749 P < 0.0001 for CD3⁺ and ρ = 0.775 P < 0.0001 for Mac3⁺; N = 35). Increased myocardial TF expression was associated with a 2-fold elevated plasma activity (P < 0.05 vs. non-infected controls). In the human hearts, the TF expression correlated postively with an endothelial cell activation marker (ρ = 0.523 P < 0.0001 for CD62E; N = 54). Viral myocarditis is a hypercoagulative state which is associated with increased myocardial TF expression and activity. Upregulation of TF contributes to a systemic activation of the coagulation cascade.     

CD4 coating, but not CD4 depletion, is a predictor of efficacy with primatized monoclonal anti-CD4 treatment of active rheumatoid arthritis

OBJECTIVE: Double blind studies were conducted with the anti-CD4 monoclonal antibody (Mab) keliximab in patients with active, stable rheumatoid arthritis (RA), to confirm preliminary evidence of efficacy and safety from open. uncontrolled studies. METHODS: We enrolled 136 and 186 patients into 2 consecutive, randomized, double blind trials, with similar populations [apart from inclusion of disease modifying antirheumatic drug (DMARD)-na?ve patients in Study 2]. Patients received 4 weeks intravenous placebo or keliximab [40, 80, 120, or 140 mg twice weekly (bw), or 240 mg once weekly (ow)].The primary endpoint was the American College of Rheumatology (ACR) 20 response criteria, one week after the end of treatment. RESULTS: ACR 20 response rates in Study I were 19%, 42%, 51%*, and 69%* (*p < 0.05 compared to placebo), with placebo, 40, 80, or 140 mg keliximab bw, respectively. The response rates in Study 2 were 30%, 39%, 46% and 47% with placebo, 80 or 120 mg bw, or 240 mg keliximab ow, respectively. In the 2 studies, there was a dose dependent increase in peripheral blood CD4+ T cell coating with keliximab, but a different pattern of CD4 depletion was seen. While only 12% of keliximab treated patients in Study I had CD4 counts below 250 cells/mm3 at the end of the treatment period, 47% fell below this level in Study 2. Clinical response was not correlated with CD4 depletion, but was correlated with CD4+ T cell coating with keliximab. CONCLUSION: Coating of peripheral blood CD4+ T cells with keliximab, but not CD4 depletion, is a determinant of clinical response.     

Four new cases of congenital secondary hypothyroidism due to a splice site mutation in the thyrotropin-beta gene: phenotypic variability and founder effect

Isolated TSH deficiency is a rare cause of congenital hypothyroidism. We here report four children from two consanguineous Turkish families with isolated TSH deficiency. Affected children who were screened at newborn age had an unremarkable TSH result and a low serum TSH level at diagnosis. Age at diagnosis and clinical phenotype were variable. All affected children carried an identical homozygous splice site mutation (IVS2 + 5 G--> A) in the TSHbeta gene. This mutation leads to skipping of exon 2 and a loss of the translational start codon without ability to produce a TSH-like protein. However, using specific monoclonal antibodies, we detected a very low concentration of authentic, heterodimeric TSH in serum, indicating the production of a small amount of correctly spliced TSH mRNA. By genotyping all family members with polymorphic markers at the TSHbeta locus, we show that the mutation arose on a common ancestral haplotype in three unrelated Turkish families indicating a founder mutation in the Turkish population. These results suggest that this TSHbeta mutation is among the more common TSHbeta gene mutations and stress the need for a biochemical and molecular genetic workup in children with symptoms suggestive of congenital hypothyroidism, even when the neonatal TSH screening is normal.     

In Acute Myocardial Infarction Liver Parameters Are Associated With Stenosis Diameter

Detection of high-risk subjects in acute myocardial infarction (AMI) by noninvasive means would reduce the need for intracardiac catheterization and associated complications. Liver enzymes are associated with cardiovascular disease risk. A potential predictive value for liver serum markers for the severity of stenosis in AMI was analyzed.Patients with AMI undergoing percutaneous coronary intervention (PCI; n = 437) were retrospectively evaluated. Minimal lumen diameter (MLD) and percent stenosis diameter (SD) were determined from quantitative coronary angiography. Patients were classified according to the severity of stenosis (SD ≥ 50%, n = 357; SD < 50%, n = 80). Routine heart and liver parameters were associated with SD using random forests (RF). A prediction model (M10) was developed based on parameter importance analysis in RF.Age, alkaline phosphatase (AP), aspartate aminotransferase (AST), and MLD differed significantly between SD ≥ 50 and SD < 50. Age, AST, alanine aminotransferase (ALT), and troponin correlated significantly with SD, whereas MLD correlated inversely with SD. M10 (age, BMI, AP, AST, ALT, gamma-glutamyltransferase, creatinine, troponin) reached an AUC of 69.7% (CI 63.8–75.5%, P < 0.0001).Routine liver parameters are associated with SD in AMI. A small set of noninvasively determined parameters can identify SD in AMI, and might avoid unnecessary coronary angiography in patients with low risk. The model can be accessed via http://stenosis.heiderlab.de.     

Analytical and between-subject variation of thrombin generation measured by calibrated automated thrombography on plasma samples*

Background: The Calibrated Automated Thrombography (CAT) is an in vitro thrombin generation (TG) assay that holds promise as a valuable tool within clinical diagnostics. However, the technique has a considerable analytical variation, and we therefore, investigated the analytical and between-subject variation of CAT systematically. Moreover, we assess the application of an internal standard for normalization to diminish variation.

Methods: 20 healthy volunteers donated one blood sample which was subsequently centrifuged, aliquoted and stored at ?80?°C prior to analysis. The analytical variation was determined on eight runs, where plasma from the same seven volunteers was processed in triplicates, and for the between-subject variation, TG analysis was performed on plasma from all 20 volunteers. The trigger reagents used for the TG assays included both PPP reagent containing 5?pM tissue factor (TF) and PPPlow with 1?pM TF. Plasma, drawn from a single donor, was applied to all plates as an internal standard for each TG analysis, which subsequently was used for normalization.

Results: The total analytical variation for TG analysis performed with PPPlow reagent is 3–14% and 9–13% for PPP reagent. This variation can be minimally reduced by using an internal standard but mainly for ETP (endogenous thrombin potential). The between-subject variation is higher when using PPPlow than PPP and this variation is considerable higher than the analytical variation.

Conclusion: TG has a rather high inherent analytical variation but considerable lower than the between-subject variation when using PPPlow as reagent.     

Analysis of late risk of systemic blood pressures <120/80 mm Hg

We studied categories of blood pressure (BP) <120/80 mm Hg as predictors of hypertension 10 to 22 years later by logistic regression analyses with 6 covariates. There was progressively increased risk for subjects with systolic BP 100 to 109 and 110 to 119 mm Hg (vs <100 mm Hg) or diastolic BP 70 to 74 and 75 to 79 mm Hg (vs <70 mm Hg). These relations were similar in men, women, and several ethnic groups but stronger in subjects <40 years old. These data suggest a definition of optimal BP of <100/70 mm Hg, similar to usual BP levels in children <10 years old.     

“Pinopodes” and Implantation

Reviews in Endocrine and Metabolic Disorders -     

Experiences with the human tumor colony-forming assay in gynecologic malignancies

Summary Tumor samples from 74 patients with gynecologic malignancies including breast cancer were processed in a soft agar colony-forming assay. None of the samples resulted in a pure single cell suspension. Of the 10 samples meeting our criteria of evaluability for chemosensitivity testing, only 5 samples showed in vitro sensitivity to any drug. Of the 3 evaluable correlations between in vitro and in vivo results, 2 were correct. Due to the low rate of evaluable samples the assay has only limited value in the assignment of chemotherapeutic drugs for patients treated at our institution.This work was supported in part by the Gesellschaft zur Bekämpfung der Krebskrankheiten Nordrhein-Westfalen