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The distribution and ultrastructure of capitate glandular trichomes (GTs) in Flourensia species (Asteraceae) have been recently elucidated, but their metabolic activity and potential biological function remain unexplored. Selective nonvolatile metabolites from isolated GTs were strikingly similar to those found on leaf surfaces. The phytotoxic allelochemical sesquiterpene (-)-hamanasic acid A ((-)-HAA) was the major constituent (ca. 40%) in GTs. Although GTs are quaternary ammonium compounds (QACs)-accumulating species, glycine betaine was not found in GTs; it was only present in the leaf mesophyll. Two (-)-HAA accompanying surface secreted products: compounds 4-hydroxyacetophenone (piceol; 1) and 2-hydroxy-5-methoxyacetophenone (2), which were isolated and fully characterized (GC/MS, NMR), were present in the volatiles found in GTs. The essential oils of fresh leaves revealed ca. 33% monoterpenes, 26% hydrocarbon- and 30% oxygenated sesquiterpenes, most of them related to cadinene and bisabolene derivatives. Present results suggest a main role of GTs in determining the volatile and nonvolatile composition of F. campestris leaves. Based on the known activities of the compounds identified, it can be suggested that GTs in F. campestris would play key ecological functions in plant-pathogen and plant-plant interactions. In addition, the strikingly high contribution of compounds derived from cadinene and bisabolene pathways, highlights the potential of this species as a source of high-valued bioproducts.

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The increase in clinical trials assessing the efficacy of cell therapy for structural and functional regeneration of the nervous system in diseases related to the aging brain is well known. However, the results are inconclusive as to the best cell type to be used or the best methodology for the homing of these stem cells. This systematic review analyzed published data on SPION (superparamagnetic iron oxide nanoparticle)-labeled stem cells as a therapy for brain diseases, such as ischemic stroke, Parkinson's disease, amyotrophic lateral sclerosis, and dementia. This review highlights the therapeutic role of stem cells in reversing the aging process and the pathophysiology of brain aging, as well as emphasizing nanotechnology as an important tool to monitor stem cell migration in affected regions of the brain.

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The presence of the phytotoxic sesquiterpene (-)-hamanasic acid A {(-)HAA; 7-carboxy-8-hydroxy-1(2), 12(13)-dien-bisabolene} isolated from Flourensia campestris (FC), was investigated in the South American species of the genus, together with the evaluation of the phytotoxic activity of their leaf aqueous extracts. (-)HAA was identified and isolated from F. fiebrigii (FF) and F. oolepis (FO), being chemically (GC-MS, NMR, [a]) and biologically (bioassayed on lettuce) indistinguishable from that of FC, while no (-)HAA was found in F. hirta (FH), F. riparia (FR) and F. niederleinii (FN). Its leaf content in FF was similar to that found in FC (ca. 15 mg g-1 WT) and significantly higher than in FO (0.8 mg g-1 WT). The screening for the presence of (-)HAA in other species of Flourensia communities showed that its natural occurrence is restricted only to Flourensia species. No (-)HAA could be detected in any of the 37 -most representative- species of these communities (26 natives, 11 exotics), despite many of them belong to the same family and tribe as Flourensia spp. Leaf aqueous extracts of all Flourensia species exhibited strong inhibitory effects on lettuce germination and on root and shoot growth, regardless of the presence and content of (-)HAA. These results strongly suggest the existence of other powerful phytotoxic compounds in those Flourensia spp lacking (-)HAA. Our results clearly show that (-)HAA only pertains to some species of the genus Flourensia. Relative to previous exomorphologic groupings of the genus, our chemotaxonomic data would give support to the close link described between FC and FF, but not with FR. In addition, the fact that (-)HAA was also found in FO, which belongs to a second different line, also points out that species position in this lineage would deserve to be revisited. The restricted production of (-)HAA by Flourensia in their communities suggests its special link with the genus, and sustains its putative allelochemical role.

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PURPOSE: To assess the reproducibility of brain-activation and eye-movement patterns in a saccade paradigm when comparing subjects, tasks, and magnetic resonance (MR) systems. MATERIALS AND METHODS: Forty-five healthy adults at two different sites (n = 45) performed saccade tasks with varying levels of target predictability: predictable (PRED), position predictable (pPRED), time predictable (tPRED), and prosaccade (SAC). Eye-movement pattern was tested with a repeated-measures analysis of variance. Activation maps reproducibility were estimated with the cluster overlap Jaccard index and signal variance coefficient of determination for within-subjects test-retest data, and for between-subjects data from the same and different sites. RESULTS: In all groups latencies increased with decreasing target predictability: PRED < pPRED < tPRED < SAC (P < 0,001). Activation overlap was good to fair (>0.40) in all tasks in the within-subjects test-retest comparisons and poor (<0.40) in the tPRED for different subjects. The overlap of the different tasks for within-groups data was higher (0.40-0.68) than for the between-groups data (0.30-0.50). Activation consistency was 60-85% in the same subjects, 50-79% in different subjects, and 50-80% in different sites. In SAC, the activation found in the same and in different subjects was more consistent than in other tasks (50-80%). CONCLUSION: The predictive saccade tasks produced evidence for brain-activation and eye-movement reproducibility.

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An aqueous extract from Flourensia campestris (Asteraceae) dry aerial parts showed strong inhibition on the germination and growth of Lactuca sativa. Based on bio-guided chromatographic fractionation of aq. extracts from dry and fresh leaves and spectroscopic means, (-)-hamanasic acid A (7-carboxy-8-hydroxy-1(2), 12(13)-dien-bisabolene (1)) was isolated as the most inhibitory active principle on germination (ECg(50)=2.9 mM) and on root (ECr(50)=1.5 mM)/shoot (ECs(50)=2.0 mM) growth. As measured by GC, and correlated with a simple designed 2D-TLC, compound 1 was distributed throughout the plant, with a remarkably high concentration (1.6%) in the leaves and the inflorescences. At least a quarter of the amount of 1 was found in aqueous extracts suggesting that leaching would be a key route for its release into the environment. By contrast, leaf essential oils (HD) between 0.5 and 1.5 µl ml(-1) did not show herbicidal effects and 1 was not found in them (TLC) nor among volatiles (HS-SPME). Volatile compositions were assessed by GC-FID and GC-MS and led to the identification of 23 compounds (4 monoterpenes and 19 sesquiterpenes) with a wide seasonal (spring-summer%) variation, represented principally by bicyclo-germacrene (37-6%), spathulenol (4-32%), globulol (20-0%), beta-caryophyllene (15-6%), caryophyllene oxide (1-13%) and bicycloelemene (10-1%), respectively. The high amount of 1 in F. campestris together with its feasibility of being extracted with water suggest that (-)-hamanasic acid A is an allelochemical in this species. Species-specific studies must be carried out to evaluate the potential of 1 as a natural herbicidal compound.

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OBJECTIVE: To refine the disease-specific health-related quality of life measure in immune (idiopathic) thrombocytopenic purpura (ITP) and to determine its validity, reliability, and responsiveness to change. STUDY DESIGN: The initial phase involved cognitive debriefing of 12 families, on the basis of which the measure was modified and then named Kids' ITP Tools (KIT). The measure was administered on 2 occasions with the Pediatric Quality of Life Inventory (PedsQL) to 41 patients with acute ITP and 49 patients with chronic ITP, 2 to 18 years old, and their parents (proxy-respondents) at 6 North American centers. RESULTS: Patients with acute ITP had lower scores when compared with patients with chronic ITP (child 64 versus 76, proxy 69 versus 77). The KIT moderately correlated with the PedsQL. Child versus proxy KIT scores showed moderate correlation, and the KIT was superior to the PedsQL. Test-retest reliability was substantial in the child report, but only moderate for the proxy report, similar to the PedsQL. The KIT showed a mean score change of 13 in the child and 15 in the proxy, which was greater than the PedsQL child's change of 7 and proxy change of 5. CONCLUSION: The KIT is valid, with good distinction between acute and chronic ITP and a moderate correlation with the PedsQL. The KIT demonstrated reliability comparable with that of the PedsQL, yet it was more responsive to change. Therefore the KIT can be used as an outcome measure in future clinical trials of childhood ITP.

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BACKGROUND: Henoch-Schõnlein purpura (HSP) is a systemic vasculitis involving small vessels with the deposition of immune complexes containing IgA. It has been extensively studied in children, but in adults, its natural history is much less known. OBJECTIVES: to report a series of patients with HSP presenting in their adulthood. PATIENTS AND METHODS: the Minas Gerais Vasculitis Study Groupïs Members (MGVSG) were invited to report patients with HSP who appeared in their adulthood. A standardized retrospective chart review was done. RESULTS: eleven patients, two male and nine female, age 39.4 +/- 20.1 yearsold were studied. Nine patients presented purpura, seven presented arthritis, four patients had gastrointestinal involvement and ten patients (91 percent) presented glomerulonephritis (GN). Eight patients were subjected to renal biopsies. Six of them presented endocapillary proliferative GN and only two of them had minimal mesangial proliferation. In the other three patients, HSP was confirmed by skin biopsies. All patients received steroids, in five of them steroids were combined with other immunosuppressive agents. After a follow-up of 39.0 +/- 64.6 months, four patients (36 percent) presented impairment of renal function, but only one (9 percent) developed end stage renal disease and was successfully appeared to renal transplantation. At the end of follow-up, seven patients (64 percent) are in complete remission and four in partial remission. CONCLUSION: in adulthood, HSP represents a distinct clinical syndrome with a higher frequency of renal involvement and more severe systemic vasculitis. Nevertheless, the final outcome in this series was as good as reported in children, maybe due to aggressive immunosuppressive therapy.

INTRODUÇÃO: púrpura de Henoch-Schõnlein (PHS) é uma vasculite sistêmica que acomete vasos de pequeno calibre com depósitos de imunocomplexos contendo IgA. Esta vasculite já foi extensamente estudada em crianças, mas sua história natural em adultos é menos conhecida. OBJETIVOS: descrever uma série de pacientes adultos com PHS. PACIENTES E MÉTODOS: membros do Grupo Mineiro de Estudo das Vasculites foram convidados a reportar pacientes com PHS apresentando-se na idade adulta. Foi realizada revisão padronizada de prontuários. RESULTADOS: 11 pacientes, dois homens e nove mulheres, com idade + desvio padrão (DP) de 39,4 +/- 20,1 anos foram estudados. Nove pacientes apresentaram púrpura; sete apresentaram artrite; quatro apresentaram envolvimento gastrintestinal e dez (91 por cento) pacientes apresentaram glomerulonefrite (GN). Oito pacientes foram submetidos à biópsia renal. Seis deles apresentaram GN endocapilar proliferativa e dois apresentaram apenas proeminência mesangial mínima. Em outros três pacientes, o diagnóstico de PHS foi confirmado através de biópsia de pele. Todos os pacientes receberam corticóide, em cinco associado a outros agentes imunossupressores. Após seguimento (média + DP) 39,0 + 64,6 meses, quatro pacientes (36 por cento) apresentaram comprometimento da função renal, mas apenas um (9 por cento) desenvolveu insuficiência renal terminal e foi submetido a transplante renal com sucesso. Após o seguimento, sete (64 por cento) estão em remissão completa e quatro em remissão parcial. CONCLUSÃO: em adultos, PHS representa uma entidade clínica distinta, com maior freqüência de envolvimento renal e vasculite sistêmica mais grave. Entretanto, o prognóstico nesta série foi tão bom quanto em crianças, talvez pela terapia imunossupressiva mais vigorosa.

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