The Ischemic Stroke Genetics Study (ISGS) Protocol

BACKGROUND: The molecular basis for the genetic risk of ischemic stroke is likely to be multigenic and influenced by environmental factors. Several small case-control studies have suggested associations between ischemic stroke and polymorphisms of genes that code for coagulation cascade proteins and platelet receptors. Our aim is to investigate potential associations between hemostatic gene polymorphisms and ischemic stroke, with particular emphasis on detailed characterization of the phenotype. METHODS/DESIGN: The Ischemic Stroke Genetic Study is a prospective, multicenter genetic association study in adults with recent first-ever ischemic stroke confirmed with computed tomography or magnetic resonance imaging. Patients are evaluated at academic medical centers in the United States and compared with sex- and age-matched controls. Stroke subtypes are determined by central blinded adjudication using standardized, validated mechanistic and syndromic classification systems. The panel of genes to be tested for polymorphisms includes β-fibrinogen and platelet glycoprotein Ia, Iba, and IIb/IIIa. Immortalized cell lines are created to allow for time- and cost-efficient testing of additional candidate genes in the future. DISCUSSION: The study is designed to minimize survival bias and to allow for exploring associations between specific polymorphisms and individual subtypes of ischemic stroke. The data set will also permit the study of genetic determinants of stroke outcome. Having cell lines will permit testing of future candidate risk factor genes

TB-Structure : Collective Intelligence for Exploratory Keyword Search

In this paper we address an exploratory search challenge by presenting a new (structure-driven) collaborative filtering technique. The aim is to increase search effectiveness by predicting implicit seeker’s intents at an early stage of the search process. This is achieved by uncovering behavioral patterns within large datasets of preserved collective search experience. We apply a specific tree-based data structure called a TB (There-and-Back) structure for compact storage of search history in the form of merged query trails – sequences of queries approaching iteratively a seeker’s goal. The organization of TB-structures allows inferring new implicit trails for the prediction of a seeker’s intents. We used experiments to demonstrate both: the storage compactness and inference potential of the proposed structure.peerReviewe

High genetic similarity between Polish and North European Scots pine (Pinus sylvestris L.) populations at nuclear gene loci

Nucleotide polymorphisms in a set of 32 nuclear genes were studied in 19 mountain, peatbog and lowland populations of Scots pine representing known phenotypic races and populations of presumably relict character for the species in Poland. At 29 genes, the pattern of genetic variation was compared to 11 reference populations from Northern, Western and Southern Europe. Similar levels of nucleotide polymorphism and excess of low-frequency mutations were observed in Polish populations (π tot = 0.0055, D = −0.308) and as compared to the reference samples (π tot = 0.0054, D = −0.170). Bayesian assignment and conventional frequency-based statistics indicate that Polish populations share the same genetic background at the analysed nuclear gene markers. However, the populations showed a much closer genetic relationship with North European samples than other regional groups of populations. Across the very uniform genetic background of the populations, we identified several genes with outlier patterns of haplotype, polymorphism frequency variation and departures from compound neutrality tests. Our data indicate that the Central and North European parts of the Scots pine distribution seem particularly suitable for association genetic studies to link phenotypic and genetic variation at a large geographical scale

Terapia de movimento induzido pela restrição na hemiplegia: um estudo de caso único Constraint-induced movement therapy in hemiplegia: a single-subject study

A terapia de movimento induzido por restrição (TMIR) tem mostrado resultados positivos em indivíduos hemiparéticos após acidente vascular cerebral; consiste na contenção do membro superior não-afetado e treinamento intensivo do membro afetado. Este estudo visou documentar longitudinalmente os efeitos da TMIR na funcionalidade do membro superior de um indivíduo com hemiparesia esquerda crônica. Neste estudo de caso único tipo ABA, as fases linha de base (A) duraram duas semanas e a intervenção (B) compreendeu a contenção do membro sadio com um splint e cinco sessões semanais de 3 horas de treino do membro superior afetado, durante duas semanas. As medidas de funcionalidade Action Research Arm (ARA) e de qualidade de movimento e destreza Wolf Motor Function Test (WMFT) foram coletadas cinco vezes por semana, e a medida de qualidade e freqüência de uso do membro superior, Motor Activity Log (MAL), uma vez por semana por seis semanas. Os dados coletados foram tratados estatisticamente. Os resultados mostram ganhos significativos na qualidade de movimento (WMFT) durante a intervenção (p<0,05), mantidos no follow-up (p>0,05). Quanto à destreza (WMFT) e funcionalidade (ARA), foram detectadas tendências significativas de ganho durante as quatro primeiras semanas; após a intervenção, houve estabilização do desempenho (p<0,05). A análise do MAL acusou efeitos sem relevância clínica. Os resultados mostram que a TMIR propiciou ganhos de desempenho motor do paciente com hemiparesia crônica.<br>Constraint-induced movement therapy (CIMT) consists of restraining movement of the non-affected arm while providing intensive training of the affected upper extremity. Positive results have been reported after CIMT in individuals with hemiparesis due to stroke. This study is a longitudinal, ABA-design documentation of the effects of CIMT on upper extremity function of an individual with chronic left hemiparesis. Baseline phases (A) lasted two weeks and intervention (B) involved restrain of the non-affected arm with a splint and five three-hour weekly sessions of training of the affected arm, for two weeks. During the six study weeks upper extremity function was assessed by means of the Action Research Arm (ARA) and movement quality and dexterity were assessed with the Wolf Motor Function Test (WMFT), five times a week. Quality and frequency of use of the upper extremity were assessed by the Motor Activity Log (MAL) once a week. Collected data were statistically analysed. Results showed significant gains in quality of movement (WMFT) during intervention (p<0.05), which were maintained during follow-up (p>0.05). As to dexterity (WMFT) and functioning (ARA), significant gain trends were detected during the first four weeks, performance having stabilised thereafter (p>0.05). MAL analysis did not detect any clinically relevant change. This study thus documented motor performance gains after CIMT in a patient with chronic hemiparesis

Bioturbation of sediments by benthic macroinvertebrates and fish and its implication for pond ecosystems: a review

Bioturbation of bottom sediments at the sediment–water interface is currently gaining more attention in studies dealing with the functioning of aquatic ecosystems. Such bioturbation can be caused by a variety of benthic macroinvertebrates or benthivorous fish that forage and burrow various bottom tubes, holes and pits. Thus, the processes involved may either be a result of direct interception by benthic animals, e.g., through bioresuspension of particles or through food ingestion and biodeposition, or of other indirect effects, e.g., changes in the physical properties of sediments or through the constructions mentioned above, along with corresponding changes in pond ecosystem functioning. The most distinct effect of benthivorous fish bioturbation activities is an increase in the turbidity of the water, which can lead to many subsequent knock-on effects, including inhibition of phytoplankton and submersed macrophyte growth with resulting alterations in physico-chemical water conditions. The importance of benthic macroinvertebrates and fish in bioturbation processes is also indicated by an increase in the numbers of resting cyanobacterial colonies recruited due to bioturbation of bottom sediments