Leukemia in Patients with Klinefelter Syndrome: A Report of Two Cases.

Klinefelter syndrome (KS) is a chromosome abnormality characterized by a 47, XXY karyotype associated with hypogonadism and infertility. We present two cases of leukemia in patients with KS. The first patient presented with acute promyelocytic leukemia. He relapsed after the end of treatment. The second patient was diagnosed with chronic myeloid leukemia. Treatment with imatinib failed and the patient presented with myeloid blast crisis.

Modeling shrub encroachment in subalpine grasslands under different environmental and management scenarios.

Woody plants are spreading in many alpine and subalpine ecosystems and are expected to continue increasing in response to land abandonment and global warming. This encroachment threatens species diversity, and considerable efforts have been deployed to control it. In this study, we combined a lattice model and field data to investigate the efficiency of different management strategies in controlling shrub encroachment in alpine grasslands. The model parameter values were estimated in the field based on the thorny shrub Echinospartum horridum (erizón) which is currently encroaching in central Spanish Pyrenees. Our study shows that encroachment could accelerate if climate warming continues. Different management scenarios consisting of a gradient of livestock pressures, fire events and mechanical removal were simulated to identify scenarios able to control the expansion of shrubs into grasslands. Our study shows that grazing alone cannot stop encroachment. Rather, a combination of grazing and shrub removal (either by fire or mechanical removal) is needed, and our model can help estimate the frequency and intensities of the shrub removal. This model can be used to investigate the consequences of different management scenarios and environmental variability which could be of practical value in the preservation of alpine grasslands.

[Safety and efficacy of botulinum toxin in hemifacial spasm]. / Efficacité et tolérance de la toxine botulique dans l'hémispasme facial.

UNLABELLED: Given the failure of pharmacologic and surgical treatment in the management of hemifacial spasm, the use of botulinum toxin as first line therapy is interesting. PURPOSE: To evaluate the safety and efficacy of type A botulinum toxin in the treatment of hemifacial spasm. PATIENTS AND METHODS: We conducted a retrospective, descriptive and comparative study of 25 patients with hemifacial spasm followed in the ophthalmology department of Habib Thameur hospital in Tunis over the period from June 2003 to June 2009. All patients received injections of botulinum toxin type A (Botox). RESULTS: We carried out 168 Botulinum A toxin injections (Botox) with an average of 6.85 ± 4.32 injections per patient. Doses varied between 12.5 U and 28 U Botox. A good response to treatment was observed in 92% of patients with a satisfactory return to daily activities and work. Based on a subjective scale from 1 to 3, the average total functional benefit was 2.55 ± 0.56. Average total duration of therapeutic response was 9.35 ± 3.64 weeks. Local side effects observed were comparable to those described in the literature: ptosis (32.4%), diplopia (8.2%), drooping of the labial commissure (11.2%), lagophthalmos (21.3%), tearing (7%), dry eye (4%). No systemic complication was noted. CONCLUSION: Botulinum toxin type A provides effective short-term and medium-term results in the treatment of hemifacial spasm. It is well tolerated locally and systemically. This safety and efficacy make it a valuable therapeutic alternative in the management of hemifacial spasm.

Changes in diatom patch-size distribution and degradation in a spatially self-organized intertidal mudflat ecosystem.

Self-organized spatial patterns have been proposed as possible indicators for regime shifts in ecosystems. Until now, this hypothesis has only been tested in drylands. Here, we focus on intertidal mudflats where regular spatial patterns develop in early spring from the interaction between diatom growth and sedimentation but disappear when benthic herbivore abundance increases in early summer, accompanied by a dramatic shift to a bare mudflat. We followed the patch-size distributions of diatom biofilms during this degradation process. As time progressed, we found a temporal change in the spatial configuration occurring simultaneously with the loss of the diatom-sediment feedback. This indicates a gradual failure in time of the self-organization process that underlies regular patterning in this ecosystem. The path to degradation co-occurred with the loss of the larger patches in the ecosystem, which resulted in a decrease of the truncation in the patch-size distribution. Hence, our study in mudflat ecosystems confirms the general hypothesis that spatial patterns can provide important clues about the level of degradation. Nevertheless, our study highlights the need for thorough study about the type of spatial patterns and the nature of the underlying feedbacks before a reliable assessment of ecosystem status can be made, as changes in patch-size distribution differed markedly with those observed in other ecosystems.

The role of reproductive plant traits and biotic interactions in the dynamics of semi-arid plant communities.

The dynamics of semi-arid plant communities are determined by the interplay between competition and facilitation among plants. The sign and strength of these biotic interactions depend on plant traits. However, the relationships between plant traits and biotic interactions, and the consequences for plant communities are still poorly understood. Our objective here was to investigate, with a modelling approach, the role of plant reproductive traits on biotic interactions, and the consequences for processes such as plant succession and invasion. The dynamics of two plant types were modelled with a spatially-explicit integrodifferential model: (1) a plant with seed dispersal (colonizer of bare soil) and (2) a plant with local vegetative propagation (local competitor). Both plant types were involved in facilitation due to a local positive feedback between vegetation biomass and soil water availability, which promoted establishment and growth. Plants in the system also competed for limited water. The efficiency in water acquisition (dependent on reproductive and growth plant traits) determined which plant type dominated the community at the steady state. Facilitative interactions between plant types also played an important role in the community dynamics, promoting establishment in the driest conditions and recovery from low biomass. Plants with vegetative propagation took advantage of the ability of seed dispersers to establish on bare soil from a low initial biomass. Seed dispersers were good invaders, maintained high biomass at intermediate and high rainfall and showed a high ability in taking profit from the positive feedback originated by plants with vegetative propagation under the driest conditions. However, seed dispersers lost competitiveness with an increasing investment in fecundity. All together, our results showed that reproductive plant traits can affect the balance between facilitative and competitive interactions. Understanding this effect of plant traits on biotic interactions provides insights in processes such as plant succession and shrub encroachment.

[Central retinal vein occlusion and internal carotid artery hypoplasia: a case report]. / Occlusion de la veine centrale de la rétine et hypoplasie de l'artère carotide interne: à propos d'un cas.

INTRODUCTION: Retinal vein occlusion is usually encountered in the elderly and is often associated with systemic vascular disease. It is rarer in young subjects and requires a serious etiological search to best adapt the treatment. OBSERVATION: We report the case of a central retinal vein occlusion (CRVO) in a 26-year-old patient who had no pathological history, discovered at a sudden decline of vision in the right eye, reduced to light perception. Fundus examination and retinal angiography showed an edematous CRVO. Radiologic imaging revealed a narrowing of the right carotid canal, probably congenital, and a reduction in the size of the right common carotid artery and internal carotid artery. Progression was favorable without treatment, and visual acuity improved to 8/10. CONCLUSION: The etiological investigation in retinal vein occlusion in young people must be exhaustive. The visual prognosis is variable and may depend on the etiology.

Benzamides derived from 1,2-diaminocyclopropane as novel ligands for human D2 and D3 dopamine receptors.

Benzamides (3a-f) derived from 4-amino-5-chloro-2-methoxybenzoic acid and either cis or trans 1,2-diaminocyclopropane were synthesised and were evaluated in binding assays employing, bovine striatal D2 receptors, recombinant human hD2 and hD3 receptors expressed in CHO cells and rat, cortical 5-HT3 and striatal 5-HT4 receptors. The cis and trans isomers of the derivatives were isolated and characterised. The results demonstrated the superiority of the cis conformers over the trans conformers in dopamine receptor binding assays (Ki hD2 = 13.4 and 6.9 nM and Ki hD3 = 17.7 and 4.5 nM for the cis-3b and cis-3f compounds, respectively; Ki hD2 = 816 and >l000 nM and Ki hD3 = 469 and >1000 nM for the corresponding trans-3b and trans-3f compounds respectively). The cis compounds are folded: the benzamide group and the basic nitrogen atom were in a syn relationship. Compound 3f can be superimposed with a conformation of the tropane derivative, BRL 25594, having the benzyl group in an axial position to give a suitable fit, indicating that both compounds may have a common binding site in the dopamine receptor.