Global lower limb muscle coactivation during walking at different speeds: Relationship between spatio-temporal, kinematic, kinetic, and energetic parameters

Muscle coactivation is the mechanism that regulates the simultaneous activity of antagonist muscles around the same joint. During walking, muscle joint coactivation varies within the gait cycle according to the functional role of the lower limb joints. In the present study, we used a time-varying multi-muscle coactivation function (TMCf) with the aim of investigating the coactivation of 12 lower limb muscles and its relationship with the gait cycle, gait speed (low, self-selected, and fast), ground reaction force, gait variability, and mechanical energy consumption, and recovery in a sample of 20 healthy subjects. Results show that the TMCf is speed dependent and highly repeatable within and between subjects, similar to the vertical force profile, and negatively correlated with energy recovery and positively correlated with both energy consumption and balance-related gait parameters. These findings suggest that the global lower limb coactivation behavior could be a useful measure of the motor control strategy, limb stiffness, postural stability, energy efficiency optimization, and several aspects in pathological conditions.

Potentiating Effect of Clopidogrel and SR 46349, a Novel 5-HT2 Antagonist, on Streptokinase-Induced Thrombolysis in the Rabbit

Current thrombolytic strategies have a number of important shortcomings including resistance to recanalization and development of acute reocclusion. The purpose of this study was to investigate whether the lysis of venous thrombi by streptokinase could be enhanced by SR 46349, a novel 5-HT2 receptor antagonist, or clopidogrel, an analogue of ticlopidine. The activity of these compounds was evaluated by following the lysis of radiolabelled fibrin under a continuous infusion of streptokinase (4,000 IU kg−1 h−1 over 4 h). Streptokinase alone induced 42% thrombolysis when compared to saline. The i. v. co-administration of SR 46349 or clopidogrel (10 mg/kg) enhanced significantly streptokinase-induced thrombolysis. Thrombolysis measured by [125I]-fibrinogen lysis increased to 65 and 59% respectively. This efficacy was achieved without additional prolongation of the template bleeding time observed with streptokinase alone.

Thus, the concomitant use of a 5-HT2 receptor antagonist or an anti-ADP agent during streptokinase therapy may facilitate clot lysis.

Antithrombotic Activity of SR 46349, a Novel, Potent and Selective 5-HT2 Receptor Antagonist

SR 46349 (trans-4-[(3Z)3-(2-dimethylaminoethyl)oxyimino-3(2-fluorophenyl)propen-1-yl] phenol, hemifumarate) is the first member of a newly-developed 5-HT2 antagonist series. SR 46349 potently inhibited serotonin-induced aggregation of rabbit and human platelets (IC50 = 1 and 3.9 nM respectively) but had no effect on the action of other platelet aggregating agents. SR 46349 was 118 and 25 times more potent than ketanserin against 5-HT + epinephrine-induced aggregation of rabbit and human platelets respectively.

A single per os administration of SR 46349 (1 mg/kg) resulted in a strong inhibition of 5-HT + epinephrine-induced platelet aggregation in the rabbit as measured ex vivo (67% inhibition, 6 h after the administration). Intravenous or oral administration of SR 46346 inhibited in a dose-dependent manner venous thrombosis induced by ligature of the jugular vein of rabbits whose blood was made hypercoagulable by i.v. administration of tissue thromboplastin. The doses of SR 46349 which inhibited 50% of thrombus formation were 1.5 ± 0.8 mg/kg and 17 ± 0.5 mg/kg after i.v. or oral administration respectively. When given i.v. to rabbits, SR 46349 exhibited a dose-dependent antithrombotic effect in an arterio-venous shunt model. Significant increase of the bleeding time was observed after the i.v. administration of 5 mg/kg of SR 46349 (3-fold increase). In dogs, SR 46349 inhibited cyclic coronary artery blood flow variations, complete abolition of CFVs being achieved after the i.v. administration of 0.5 mg/kg.

In conclusion, SR 46349 is a highly potent, selective antagonist of serotonin in vitro and is to be considered as a potent, orally active antithrombotic agent.

Assessing Restoration Effects on River Hydromorphology Using the Process-based Morphological Quality Index in Eight European River Reaches

The Morphological Quality Index (MQI) and the Morphological Quality Index for monitoring (MQIm) have been applied to eight case studies across Europe with the objective of analyzing the hydromorphological response to various restoration measures and of comparing the results of the MQI and MQIm as a morphological assessment applied at the reach scale, with a conventional site scale physical-habitat assessment method. For each restored reach, the two indices were applied to the pre-restoration and post-restoration conditions. The restored reach was also compared to an adjacent, degraded reach. Results show that in all cases the restoration measures improved the morphological quality of the reach, but that the degree of improvement depends on many factors, including the initial morphological conditions, the length of the restored portion in relation to the reach length, and on the type of intervention. The comparison with a conventional site scale physical-habitat assessment method shows that the MQI and MQIm are best suited for the evaluation of restoration effects on river hydromorphology at the geomorphologically-relevant scale of the river reach.

New tools for the hydromorphological assessment and monitoring of European streams

Hydromorphological stream assessment has significantly expanded over the last years, but a need has emerged from recent reviews for more comprehensive, process-based methods that consider the character and dynamics of the river with greater accuracy. With this as a focus, a series of hydromorphological tools have been developed and/or further extended in Europe within the context of the REFORM (REstoring rivers FOR effective catchment Management) project. The aim of this paper is to present the set of REFORM hydromorphological assessment methods and, based on some examples of their application, to illustrate and discuss their synergic use, specific features, limitations and strengths. This assessment and monitoring includes three tools: the Morphological Quality Index (MQI), the Morphological Quality Index for monitoring (MQIm), and the Geomorphic Units survey and classification System (GUS). These tools constitute the assessment phase of an overall multi-scale, process-based hydromorphological framework developed in REFORM. The MQI is aimed at an assessment, classification and monitoring of the current morphological state; the MQIm aims at monitoring the tendency of morphological conditions (enhancement or deterioration); the GUS provides a characterization, classification and monitoring of geomorphic units. A series of examples are used to illustrate the potential range of application, including: (i) an assessment of morphological conditions; (ii) an assessment of the morphological effects of restoration projects; (iii) an evaluation of the geomorphic impacts of interventions for risk mitigation; and (iv) an integrated use of MQI and GUS to assess and characterise morphological conditions. Finally, some of the main features, strengths and peculiarities of the three hydromorphological tools are discussed with the support of examples of their application.

Evaluation of Symptoms and Prevention of Cancer in Menopause: The Value of Vulvar Exam

Vulvar and vaginal atrophy (VVA), is a chronic medical condition experienced by postmenopausal women, with prevalence estimated ranging from 10% to 50% [1]. VVA is characterized by a constellation of symptoms, that may affect daily activities, sexuality, relationships, and quality of life [3]. Early recognition and effective treatment of VVA may enhance sexual health and the quality of life of women and their partners. Some vulvar conditions such as lichen sclerosus are more prevalent in the postmenopausal years. Lichen sclerosus has been suggested as a precursor of Vulvar squamous cell carcinoma. The vulvar exam in post-menopausal women plays an essential role in prevention of cancer because it allows to identify women who should undergo vulvar skin biopsy in order to early detect pre-neoplastic lesions for early diagnosis of cancer of the vulva.

Effectiveness of Immunoglobulins for the Prevention of Systemic Infections : A Meta-Analysis of 8 Clinical Studies in Premature Infants

The prophylactic administration of immunoglobulins to preterm neonates has a controversial effectiveness in reducing the incidence of nosocomial infections. Since the clinical trials conducted so far have given conflicting results, a metaanalysis was carried out to summarise the overall information presently available on this issue. Eight randomised clinical trials were identified by our literature search that met the inclusion criteria of our meta-analysis. In each study, the effectiveness of intravenous immunoglobulins was compared with that of no treatment or placebo. The overall number of patients included in our metaanalysis was 3739. The end-point was the incidence of proven infections. The results of our meta-analysis demonstrate that prophylactic immunoglobulins significantly reduced the incidence of proven infections (pooled odds ratio = 0.79, 95% CI: 0.69 to 0.91; p = 0.0014; reduction in the incidence of infection from 23.2 to 19.3%). There was, however, a significant intertriai heterogeneity. A cost-effectiveness analysis indicated that the prophylactic administration of immunoglobulins implies a cost of approximately $US8000 to prevent each case of infection in premature infants. This cost seems to be at least equal to the cost of treating an episode of sepsis in an infant.