Silicon location through backscattered electron imaging and X-ray microanalysis in leaves of Cyperus ligularis L. and Rhynchospora aberrans C. B. Clarke (Cyperaceae)

(Silicon location through backscattered electron imaging and X-ray microanalysis in leaves of Cyperus ligularis L. and Rhynchospora aberrans C. B. Clarke (Cyperaceae)). The Cyperaceae show the ability to incorporate silicon by depositing colloidal silica, which is recorded by the occurrence of projections in the form of cones, in inner tangential walls of some epidermal cells or "silica cells". Leaves of C. ligularis and R. aberrans were analyzed through the technique of electron backscatter. Cyperus ligularis accumulates silica, in addition to "silica cells", in some stomata, trichomes and the cell walls that surround the cavities of the aerenchyma. The silica in the latter occurs in various forms; however, the cells located near the vascular bundles have conical projections, similar to those of the epidermis. Rhynchospora aberrans presents "silica cells" whose projections have tapered "satellites". In this species, silica also occurs in stomata and certain epidermal cells adjacent to them. It appears that the silicon deposition occurs in combination with the wall (with no apparent structural changes), and structures of secretion, or projections of the wall. These structural changes in the species, and location, are probably related to functional and environmental factors, especially the soil, in addition to relation with taxonomic groups.(Localização de sílica por elétrons retroespalhados em folhas de Cyperus ligularis L. and Rhynchospora aberrans C.\ud B. Clarke (Cyperaceae)). As Cyperaceae têm a capacidade de incorporação do ácido silícico mediante depósito de\ud sílica coloidal, que é registrada pela ocorrência de projeções sob a forma de cones, nas paredes tangenciais internas\ud de determinadas células epidérmicas ou “células de sílica”. Folhas de C. ligularis e R. aberrans foram analisadas pela\ud técnica de elétrons retroespalhados. C. ligularis além de acumular sílica nas “células de sílica”, acumula também em\ud alguns estômatos, nos tricomas e nas paredes das células que contornam as cavidades do aerênquima. Este último\ud apresenta formas diversas, entretanto, as células que se localizam junto aos feixes vasculares mostram projeções cônicas,\ud semelhantes àquelas da epiderme. R. aberrans contém “células de silica” cujas projeções cônicas têm “satélites”.\ud A sílica também ocorre em estômatos específi cos e em células epidérmicas contíguas aos mesmos. Constata-se que\ud a deposição de sílica ocorre tanto em combinação com a parede (sem modifi cações estruturais aparentes), como em\ud estruturas de secreção da mesma, ou seja, projeções da parede. Essas variações de ocorrência estrutural e de localização\ud nas espécies devem estar relacionadas com a funcionalidade, fatores ambientais, com destaque ao solo, além\ud da relação com grupos taxonômicos.CNPqCNPq [302265/2008-2

Differentiation of vascular bundles and tracheary elements in the rhizome of some Cyperaceae

Foram analisados os rizomas de Bulbostylis paradoxa Ness, Cyperus giganteus Vahl, C. odoratus L., Fuirena umbellata Rottb. e Hypolytrum schraderianum Ness. O corpo primário é resultante da atividade dos meristemas apicais e do meristema de espessamento primário (MEP). Também ocorre crescimento em espessura, que é decorrente da atividade do meristema de espessamento secundário (MES). O procâmbio e o MEP originam feixes colaterais em H. schraderianum e feixes anfivasais nas demais espécies. Entretanto, todos os feixes que têm protofloema e protoxilema são de origem procambial. O MES produz floema e xilema constituindo um tecido vascular único. Elementos de vaso foram encontrados na maioria dos caules em estrutura primária e secundária, com exceção de H. schraderianum que, na estrutura secundária, contém apenas traqueídes, informação que respalda a ocorrência de crescimento secundário nas Cyperaceae. Os elementos de vaso apresentam grande variação morfológica; em estrutura primária, geralmente são mais alongados, com apêndices. Os elementos de vaso do crescimento secundário são relativamente mais curtos, apresentam apêndices e ramificações.Were analized the rhizomes of Bulbostylis paradoxa Ness, Cyperus giganteus Vahl, C. odoratus L., Fuirena umbellata Rottb. and Hypolytrum schraderianum Ness. The primary body results from activity of primary meristems and primary thickening meristem (PTM). Secondary growth occurs too, due to the activity of the secondary thickening meristem (STM). Collateral vascular bundles are formed from procambium and MEP in H. schraderianum, and amphivasal bundles in the other species. However, all of the vascular bundles having protophloem and protoxylem are originated from procambium. Phloem and xylem are formed from MES in a single vascular tissue. Vessel elements were present in the most of the stems in primary and secondary growth, exception to H. schraderianum that has only tracheids in the last one; this information supports the occurrence of secondary growth in Cyperaceae. The vessel elements show a great morphological variation; generally, vessel elements from the primary growth, are longer and tip of vessel elements are present. The vessel elements from secondary growth are shorter and show tip of vessel elements and branchings.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico (CNPq

Physical exercises to prevent falls : a clinical trial with institutionalized elderly in the city of Goiânia in Brazil

Este estudo teve como objetivo avaliar um programa de intervenção com exercícios físicos em grupo na prevenção de quedas em idosos residentes em instituições de longa permanência. Trata-se de um ensaio clínico não randomizado realizado com 20 idosos institucionalizados na cidade de Goiânia, Brasil. As intervenções ocorreram durante cinco meses, sendo que o programa de exercícios proposto foi baseado em estudos anteriores. Medidas padronizadas foram utilizadas para avaliar quedas, equilíbrio e marcha, força muscular, flexibilidade e medo de quedas. A partir do período de 12 meses do início da intervenção houve redução significativa no número de quedas (p = 0,046). A partir do programa foram observadas diferenças significantes para pontuação das manobras de equilíbrio (p = 0,001), pontuação total das manobras de equilíbrio e marcha (p = 0,007), força muscular de preensão palmar (p = 0,001) e de membros inferiores (p < 0,001), flexibilidade do movimento de flexão dos ombros (p = 0,001). A intervenção realizada mediante um programa de exercícios mostrou-se adequada, porém, não suficiente para melhorar a marcha, flexibilidade multiarticular da coluna e quadril e medo de quedas, bem como para reduzir o número de idosos que sofreram quedas a partir do início do estudo. _________________________________________________________________________________________ ABSTRACTThe scope of this study was to evaluate an intervention program with group physical exercises to prevent falls in the elderly in long-term care institutions. This is a non-randomized clinical trial conducted with 20 institutionalized elderly people in the city of Goiânia in Brazil. The interventions occurred over the period of five months, though the proposed exercise program was based on earlier studies. Standardized measures were used to assess falls, balance and gait, muscle strength, flexibility and fear of falling. After the period of 12 months from the start of intervention there was a significant reduction in the number of falls (p = 0.046). Based on the program, significant differences were observed for point allocation of the maneuvers of balance (p = 0.001), total scores of the maneuvers of balance and gait (p = 0.007), muscle strength of hand grip (p = 0.001) and of lower limbs (p < 0.001), flexibility of movement of shoulder flexion (p = 0.001). The intervention using an exercise program proved to be adequate, albeit insufficient to improve the gait, multiple joint flexibility of the spine and hip and fear of falling, or to reduce the number of elderly people who suffered falls from the beginning of the study

Evaluation of an intervention program with group physical exercises to prevent falls in elderly living at long-term care instituions

Submitted by Marlene Santos ([email protected]) on 2017-08-07T19:38:21Z No. of bitstreams: 2 Tese - Ana Claudia Antonio Maranhão Sá- 2011.pdf: 3630030 bytes, checksum: 270c12818a43348bdb747081edfc41ac (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Approved for entry into archive by Luciana Ferreira ([email protected]) on 2017-08-08T15:01:34Z (GMT) No. of bitstreams: 2 Tese - Ana Claudia Antonio Maranhão Sá- 2011.pdf: 3630030 bytes, checksum: 270c12818a43348bdb747081edfc41ac (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)Made available in DSpace on 2017-08-08T15:01:34Z (GMT). No. of bitstreams: 2 Tese - Ana Claudia Antonio Maranhão Sá- 2011.pdf: 3630030 bytes, checksum: 270c12818a43348bdb747081edfc41ac (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2011-04-29Falls in the elderly constitute an important public worldwide health problem, because they are an important cause of morbidity and mortality among elderly. This study aimed to evaluate an intervention program with group physical exercises in the prevention of falls in elderly living at long-term care institutions (LTCI). This is a non-randomized clinical trial, conducted with 20 elderly people of both sexes, residents in two LTCI in Goiânia, Brazil. The interventions were based on previous studies and occurred three times a week for a period of 18 weeks, totaling 40 sessions of group exercises, lasting about two hours each one, in which warm-up exercises were performed, muscle strength, balance, flexibility and relaxation. Standardized measures were used to assess falls (self-reports of participants), balance and gait (Performance - Oriented Mobility Assessment - POMA - Brazil), muscular strength (Hydraulic Hand Dynamometer and 30 second chair stand test), flexibility (Goniometer commuting – Fleximeter and Chair sit-and-reach test), fear of falling (Falls Efficacy Scale - International - FES I - Brazil). After a period of twelve months from the beginning of the intervention the decrease in the number of falls was significant (p = 0.046). Significant differences were observed for POMA-Equilibrium (p = 0.001), POMA-Total (p = 0.007), muscular strength of hand grip (p = 0.001) and lower limbs (p<0.001), flexibility of the bending motion of the shoulders (p = 0.001). The intervention by a physical exercises program proved to be adequate to improve balance, muscle strength of lower and upper limbs, shoulder flexibility, helping to significantly decrease the number of falls among elderly participants, but not enough to improve gait and multiple joint flexibility of spine and hip, as well as to reduce the number of elderly who suffered falls from the beginning of the intervention program.As quedas em idosos constituem um problema de saúde pública em todo o mundo, pois são importante causa de morbidade e mortalidade entre pessoas dessa faixa etária. Assim, é necessário que os profissionais de saúde desenvolvam intervenções para prevenir essa ocorrência. Este estudo teve como objetivo geral avaliar um programa de intervenção com exercícios físicos em grupo para prevenir quedas em idosos residentes em instituições de longa permanência (ILPI). Trata-se de um ensaio clínico não randomizado realizado com 20 idosos de ambos os sexos, moradores em duas ILPI na cidade de Goiânia, Brasil. As intervenções ocorreram três vezes por semana, por um período de 18 semanas, totalizando 40 sessões de exercícios em grupo, cada uma delas com duração aproximada de 2 horas, nas quais foram realizados exercícios de aquecimento, força muscular, equilíbrio, flexibilidade e relaxamento. Medidas padronizadas foram utilizadas para avaliar quedas (autorrelato dos participantes), equilíbrio e marcha (Performance – Oriented Mobility Assessment – POMA – Brasil), força muscular (Hydraulic Hand Dynamometer e 30 segundos chair stand test), flexibilidade (Goniômetro pendular - Flexímetro e Chair sit-and-reach test) e medo de quedas (Escala de Eficácia de Quedas – Internacional –FES – I – Brasil). A partir do período de doze meses do início da intervenção, houve redução significativa (p = 0,046) no número de quedas. Foram observadas diferenças significantes para POMA-Equilíbrio (p = 0,001), POMA-Total (p = 0,007), força muscular de preensão palmar (p = 0,001) e de membros inferiores (p < 0,001) e flexibilidade do movimento de flexão dos ombros (p = 0,001). A intervenção realizada mediante um programa de exercícios físicos mostrou-se adequada para melhorar equilíbrio, força muscular de membros superiores e inferiores e flexibilidade de ombro, contribuindo para redução significativa do número de quedas entre os idosos participantes do estudo, porém não suficiente para melhorar a marcha e a flexibilidade multiarticular da coluna e quadril, bem como para reduzir o número de idosos que sofreram quedas a partir do início do programa de intervenção

Natural products as new antimitotic compounds for anticancer drug development

Cell cycle control genes are frequently mutated in cancer cells, which usually display higher rates of proliferation than normal cells. Dysregulated mitosis leads to genomic instability, which contributes to tumor progression and aggressiveness. Many drugs that disrupt mitosis have been studied because they induce cell cycle arrest and tumor cell death. These antitumor compounds are referred to as antimitotics. Vinca alkaloids and taxanes are natural products that target microtubules and inhibit mitosis, and their derivatives are among the most commonly used drugs in cancer therapy worldwide. However, severe adverse effects such as neuropathies are frequently observed during treatment with microtubule-targeting agents. Many efforts have been directed at developing improved antimitotics with increased specificity and decreased likelihood of inducing side effects. These new drugs generally target specific components of mitotic regulation that are mainly or exclusively expressed during cell division, such as kinases, motor proteins and multiprotein complexes. Such small molecules are now in preclinical studies and clinical trials, and many are products or derivatives from natural sources. In this review, we focused on the most promising targets for the development of antimitotics and discussed the advantages and disadvantages of these targets. We also highlighted the novel natural antimitotic agents under investigation by our research group, including combretastatins, withanolides and pterocarpans, which show the potential to circumvent the main issues in antimitotic therapy

Effects of Croton rhamnifolioides Essential Oil on Aedes aegypti Oviposition, Larval Toxicity and Trypsin Activity

Although numerous reports are available concerning the larvicidal potential of essential oils, very few investigations have focused on their mechanisms of action. In the present study, we have investigated the chemical composition of the leaf oil of Croton rhamnifolioides during storage and its effects on oviposition and survival of larvae of the dengue fever mosquito Aedes aegypti. In addition, we have established a possible mechanism of action for the larvicidal activity of the essential oil. GC-MS analyses revealed marked differences in the composition of oil that had been freshly isolated and that of a sample that had been stored in a sealed amber-glass vial under refrigeration for three years. However, both fresh and stored oil exhibited substantial larvicidal activities with LC50 values of 122.35 and 89.03 ppm, respectively, and oviposition deterrent effects against gravid females at concentrations of 50 and 100 µg·mL−1. These results demonstrate that the larvicidal effect of the essential oil was unchanged during three years of storage even though its chemical composition altered. Hence, the essential oil could be used in the preparation of commercial products. In addition, we observed that the trypsin-like activity of mosquito larvae was inhibited in vitro by the essential oil of C. rhamnifolioides, suggesting that the larvicidal effect may be associated with inhibition of this enzyme