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Background: The effects of current anthropogenic influences on eelgrass (Zostera marina) meadows are noticeable. Eelgrass ecological services grant important benefits for mankind. Preservation of eelgrass meadows include several transplantation methods. Evaluation of establishing success relies on the estimation of standing stock and productivity. Average leaf biomass in shoots is a fundamental component of standing stock. Existing methods of leaf biomass measurement are destructive and time consuming. These assessments could alter shoot density in developing transplants. Allometric methods offer convenient indirect assessments of individual leaf biomass. Aggregation of single leaf projections produce surrogates for average leaf biomass in shoots. Involved parameters are time invariant, then derived proxies yield simplified nondestructive approximations. On spite of time invariance local factors induce relative variability of parameter estimates. This influences accuracy of surrogates. And factors like analysis method, sample size and data quality also impact precision. Besides, scaling projections are sensitive to parameter fluctuation. Thus the suitability of the addressed allometric approximations requires clarification., Results: The considered proxies produced accurate indirect assessments of observed values. Only parameter estimates fitted from raw data using nonlinear regression, produced robust approximations. Data quality influenced sensitivity and sample size for an optimal precision., Conclusions: Allometric surrogates of average leaf biomass in eelgrass shoots offer convenient nondestructive assessments. But analysis method and sample size can influence accuracy in a direct manner. Standardized routines for data quality are crucial on granting cost-effectiveness of the method.

Recombinant factor VIIa (rFVIIa; NovoSeven, Novo Nordisk, Bagsvaerd, Denmark) appears effective and relatively safe for the treatment of bleeding and for surgical prophylaxis in patients with Glanzmann thrombasthenia as reported to the International Registry on rFVIIa and Congenital Platelet Disorders. One of the shortcomings of the Registry data is the heterogeneity of treatment protocol, including dosage, number of doses used, duration of treatment before declaration of failure, and mode of rFVIIa administration (bolus v continuous infusion). The data are not yet sufficient to define optimal regimens for various indications such as the type of bleeding or the type of procedures. The place of this drug compared to platelet transfusion in the overall management of patients with Glanzmann thrombasthenia will need to be determined in relationship to a number of challenges and unresolved issues in the clinical care of these patients. These issues include: how to improve local measures for patients with mucosal bleeds, optimal management of young women during menarche, optimal platelet transfusion regimens for various indications, the relationship between antiplatelet antibodies detected by monoclonal antibody-specific immobilization of platelet antigens (MAIPA) and effectiveness of platelet transfusion, whether there are other biological tests that may correlate with effectiveness of platelet transfusion, and management of pregnancy and delivery regarding antiplatelet immunization., (Copyright 2001 by W.B. Saunders Company.)

After a first episode of spontaneous venous thromboembolism (VTE), the risk of recurrence persists for many years. However, comprehensive data about the risk of recurrence in pediatric patients have hitherto not been reported. Thus, this study evaluated the risk of recurrent VTE among children in relation to the presence of single or combined-inherited and/or acquired causes of thrombophilia. A total of 301 patients aged neonate to 18 years (median, 6 years) who were referred for an objectively confirmed first episode of spontaneous VTE were followed prospectively for a median time of 7 years (range, 6 months to 15 years) after withdrawal of anticoagulation. All patients were studied for established acquired and inherited causes of thromboembolism. With reference to all 301 patients, one single prothrombotic risk factor was found in 176 subjects (58.5%), whereas combined defects were found in 20.6% (n = 62). Recurrent VTE occurred in 64 patients (21.3%) within a median time of 3.5 years (range, 7 weeks to 15 years) after withdrawal of anticoagulation, with a significantly shorter cumulative thrombosis-free survival in children carrying combined defects (P <.0001; chi-square, 42.2). The factor V G1691A mutation was present in the majority of patients with recurrent VTE. Including genetic defects, gender, and acquired risk factors, multivariate analysis showed that only the presence of prothrombotic defects increases the risk of recurrent VTE (single defect: odds ratio [OR], 4.6; 95% confidence interval [CI], 2.3-9.0; P <.0001; combined defect: OR, 24.0; 95% CI: 5.3-108.7; P <.0001). As a consequence of the data presented here, it is suggested that screening for genetic risk factors be done among pediatric patients with VTE.

For life-threatening hemangiomas where surgical or laser techniques are not feasible, systemic therapy with cortisone or interferon represents the therapy of choice. With response rates of 80-90%, both drugs are equally effective. Both treatments, however, might be associated with severe side-effects. Among these the risk of interferon-induced neurotoxicity has to be given special mention. Thus, the indication for systemic therapy of hemangiomas has to be made carefully, weighing up risk and benefit.