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Objective Synovial fluid (SF) plays an important role in the maintenance of articular cartilage. SF is a dynamic reservoir of proteins derived from cartilage and synovial tissue; thus, its composition may serve as a biomarker that reflects the health and pathophysiological condition of the joint. The purpose of the current study was to evaluate the osteoarthritic synovial fluid (OASF) and transforming growth factor-β1 (TGF-β1) activity in articular chondrocytes catabolic and inflammatory responses. Design Chondrocytes were seeded at passage 2 and cultured for 72 hours under different conditions. Human chondrocytes were subjected to OASF while rat chondrocytes were subjected to either healthy synovial fluid (rSF) or TGF-β1 and then assigned for cell viability analysis. In addition, the effects of OASF and TGF-β1 on chondrocytes metalloprotease (MMP)-3 and MMP-13 and interleukin-18 (IL-18) expression were evaluated by immunocytochemistry, ELISA, and reverse transcriptase-polymerase chain reaction. Results SF from osteoarthritic patients significantly induced MMP-3, MMP-13, and IL-18 receptor expression in chondrocytes. To put in evidence the inflammatory activity of OASF, healthy chondrocytes from rat were cultured with TGF-β1. In the presence of TGF-β1 these cells started to express MMP-3, MMP-13, and IL-18 genes and attached to each other forming a chondrocyte aggregated structure. Healthy SF was able to maintain a typical monolayer of rounded chondrocytes with no inflammatory response. Conclusion In summary, these observations demonstrated that TGF-β1, one of the components of OASF, has a dual effect, acting in chondrocyte maintenance and also inducing inflammatory and catabolic properties of these cells.

Psd1 is a plant defensin that has antifungal activity against several pathogenic and nonpathogenic fungi. Previous analysis of Psd1 chemical shift perturbations by nuclear magnetic resonance (NMR) spectroscopy demonstrated that this defensin interacts with phospholipids and the sphingolipid glucosylceramide isolated from Fusarium solani (GlcCer(Fusarium solani)). In this study, these interactions were evaluated by real-time surface plasmon resonance (SPR) analysis. The data obtained demonstrated that Psd1 could bind more strongly to small unilamellar vesicles (SUV)-containing GlcCer(Fusarium solani) than to SUV that was composed of phosphatidylcholine (PC) alone or was enriched with GlcCer that had been isolated from soybeans. An increase in the SPR response after cholesterol or ergosterol incorporation in PC-SUV was detected; however, SUV composed of PC:Erg (7:3; molar:molar) became unstable in the presence of Psd1, suggesting membrane destabilization. We also observed a lack of Psd1 internalization in Candida albicans strains that were deficient in the glucosyl ceramide synthase gene. Together, these data indicate that GlcCer is essential for Psd1 anchoring in the fungal plasma membrane as well as internalization.

Neste trabalho foram usadas as orientações pedagógicas atuais que tratam as disciplinas das grades curriculares como interdependentes e complementares, de modo que não haja uma fragmentação das habilidades e competências em ciclos educacionais hierarquizados. As avaliações seguiram um modelo seriado onde os alunos foram avaliados a cada semana a partir de apenas um conteúdo por vez, permitindo dessa forma que se abordasse o assunto com uma profundidade maior, pois os alunos não necessitaram dividir os estudos entre vários conteúdos, o que pulveriza sua atenção e contrinui para a superficialização dos estudos em cada unidade. Os resultados estatísticos sinalizam para uma aceitação dessa metodologia, pois atenderam aos objetivos desse trabalho, que foram confrontar a avaliação seriada com a avaliação tradicional, bem como implementar os conceitos pedagógicos atuais de ensino e avaliação proposto pelos atuais pensadores da docência superior.

This study aimed to describe phlebitis, infiltration and extravasation events in newborn infants hospitalized at the neonatal intensive care unit of a public maternity in Rio de Janeiro, Brazil. A quantitative and descriptive study was carried out, involving 36 newborns under intravenous therapy and indicated for the removal of the peripheral intravenous device. Fifty puncture sites were assessed immediately after the peripheral catheter removal, resulting in an average 1.40 punctures per infant. Complications were responsible for 48% of catheter removals before discharge from treatment, predominantly infiltration (79.2%), followed by phlebitis (16.7%) and extravasation (4.2%). To avoid aggravations and enhance the security of newborns submitted to intravenous therapy, the nursing team should periodically assess the peripheral venous access and gain knowledge on interventions needed when signs of complications are detected. O objetivo deste estudo foi descrever a ocorrência de flebite, infiltração e extravasamento em recém-nascidos internados na unidade de terapia intensiva neonatal de uma maternidade pública do Rio de Janeiro. Trata-se de um estudo quantitativo descritivo com 36 recém-nascidos em uso de terapia intravenosa e com indicação de remoção do dispositivo intravenoso periférico. Foram avaliados 50 sítios de punção imediatamente após a remoção de cateteres periféricos originando uma média de 1,40 punções venosas por neonato. As complicações foram responsáveis por 48% da remoção dos cateteres, antes da alta do tratamento, com predomínio de infiltração (79,2%), seguida por flebite (16,7%) e extravasamento (4,2%). A fim de se evitar os agravos e promover a segurança dos recém-nascidos submetidos à terapia intravenosa, a equipe de enfermagem deve avaliar periodicamente o acesso venoso periférico e obter conhecimento acerca das intervenções necessárias quando detectados sinais de complicações. El objetivo de este estudio fue describir la ocurrencia de flebitis, infiltración y extravasamiento en recién nacidos internados en la unidad de terapia intensiva neonatal de una maternidad pública de Rio de Janeiro. Se trata de un estudio cuantitativo descriptivo con 36 recién nacidos en uso de terapia intravenosa y con indicación de remoción del dispositivo intravenoso periférico. Fueron evaluados 50 sitios de punción inmediatamente después de la remoción de catéteres periféricos originando una media de 1,40 punciones venosas por neonato. Las complicaciones fueron responsables por 48% de las remociones de los catéteres, antes del alta del tratamiento, con predominio de infiltraciones (79,2%), seguida por flebitis (16,7%) e extravasamiento (4,2%). Con el fin de evitar los lesiones y promover la seguridad de los recién nacidos sometidos a terapia intravenosa, el equipo de enfermería debe evaluar periódicamente el acceso venoso periférico y obtener conocimiento acerca de las intervenciones necesarias cuando detectadas señales de complicaciones

Thyroid hormones (THs) are essential for brain development, where they regulate gliogenesis, myelination, cell proliferation and protein synthesis. Hypothyroidism severely affects neuronal growth and establishment of synaptic connections. Triiodothyronine (T3), the biologically active form of TH, has a central function in these activities. So, Myosin-Va (Myo-Va), a molecular motor protein involved in vesicle and RNA transport, is a good candidate as a target for T3 regulation. Here, we analyzed Myo-Va expression in euthyroid and hypothyroid adult rat brains and synaptosomes. We observed a reduction of Myo-Va expression in cultured neural cells from newborn hypothyroid rat brain, while immunocytochemical experiments showed a punctate distribution of this protein in the cytoplasm of cells. Particularly, Myo-Va co-localized with microtubules in neurites, especially in their varicosities. Myo-Va immunostaining was stronger in astrocytes and neurons of controls when compared with hypothyroid brains. In addition, supplementation of astrocyte cultures with T3 led to increased expression of Myo-Va in cells from both euthyroid and hypothyroid animals, suggesting that T3 modulates Myo-Va expression in neural cells both in vivo and in vitro. We have further analyzed Myo-Va expression in U373 cells, a human glioblastoma line, and found the same punctate cytoplasmic protein localization. As in normal neural cells, this expression was also increased by T3, suggesting that the modulatory mechanism exerted by T3 over Myo-Va remains active on astrocyte tumor cells. These data, coupled with the observation that Myo-Va is severely affected in hypothyroidism, support the hypothesis that T3 activity regulates neural motor protein expression, taking Myo-Va as a model. As a consequence, reduced T3 activity could supposedly affect axonal transport and synaptic function, and could therefore explain disturbances seen in the hypothyroid brain.

The harmonious development of the central nervous system depends on the interactions of the neuronal and glial cells. Extracellular matrix elements play important roles in these interactions, especially laminin produced by astrocytes, which has been shown to be a good substrate for neuron growth and axonal guidance. Glioblastomas are the most common subtypes of primary brain tumors and may be astrocytes in origin. As normal laminin-producing glial cells are the preferential substrate for neurons, and glial tumors have been shown to produce laminin, we questioned whether glioblastoma retained the same normal glial–neuron interactive properties with respect to neuronal growth and differentiation. Then, rat neurons were co-cultured onto rat normal astrocytes or onto three human glioblastoma cell lines obtained from neurosurgery. The co-culture confirmed that human glioblastoma cells as well as astrocytes maintained the ability to support neuritogenesis, but non-neural normal or tumoral cells failed to do so. However, glioblastoma cells did not distinguish embryonic from post-natal neurons in relation to neurite pattern in the co-cultures, as normal astrocytes did. Further, the laminin organization on both normal and tumoral glial cells was altered from a filamentous arrangement to a mixed punctuate/filamentous pattern when in co-culture with neurons. Together, these results suggest that glioblastoma cells could identify neuronal cells as partners, to support their growth and induce complex neurites, but they lost the normal glia property to distinguish neuronal age. In addition, our results show for the first time that neurons modulate the organization of astrocytes and glioblastoma laminin on the extracellular matrix.

Among the cells that constitute the central nervous system (CNS), astrocytes are the most abundant cells in the brain. They originate from the neural tube, differently from other glial cells of the astrocyte-like, enteric glia, which originate from the neural crest. Cerebral astrocytes interact with other brain cells such as neurons, mediated by cellular contact involving extracellular matrix (ECM) elements and the integrin of astrocytes. Interactions can also occur through exchange of soluble molecules, cytokines, and growth factors, delivered by astrocytes and the interacting cells. Of the growth factors secreted by astrocytes, members of the transforming growth factor (TGF) beta family, especially TGF-β1, are highly important. TGF-β1 acts in brain development, in adult brain homeostasis, and also in orchestrating the brain’s response to injury and/or aging. These cell–cell interactions depend on the cellular membrane plasticity expressed by biophysical forces of interaction. In parallel to the properties of normal astrocytes, a growing astrocytoma develops new malignant behavior and interactions with parenchyma that differ from those of normal astrocytes. In this chapter, we analyze important points that characterize tumor progression and discuss new therapeutic approaches to treat these tumors.

Glioblastoma (GBM) is one of the most aggressive human cancers. Despite current advances in multimodality therapies, such as surgery, radiotherapy and chemotherapy, the outcome for patients with high grade glioma remains fatal. The knowledge of how glioma cells develop and depend on the tumor environment might open opportunities for new therapies. There is now a growing awareness that the main limitations in understanding and successfully treating GBM might be bypassed by the identification of a distinct cell type that has defining properties of somatic stem cells, as well as cancer-initiating capacity - brain tumor stem cells, which could represent a therapeutic target. In addition, experimental studies have demonstrated that the combination of antiangiogenic therapy, based on the disruption of tumor blood vessels, with conventional chemotherapy generates encouraging results. Emerging reports have also shown that microglial cells can be used as therapeutic vectors to transport genes and/or substances to the tumor site, which opens up new perspectives for the development of GBM therapies targeting microglial cells. Finally, recent studies have shown that natural toxins can be conjugated to drugs that bind to overexpressed receptors in cancer cells, generating targeted-toxins to selectively kill cancer cells. These targeted-toxins are highly effective against radiation- and chemotherapy-resistant cancer cells, making them good candidates for clinical trials in GBM patients. In this review, we discuss recent studies that reveal new possibilities of GBM treatment taking into account cancer stem cells, angiogenesis, microglial cells and drug delivery in the development of new targeted-therapies.

The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

We discuss the origin and development of microglial cells and their influence on neural development. Unlike astrocytes, oligodendrocytes, and neurons, which are derived from neuroectoderm, microglial cells originate from mesoderm. Microglial hematopoietic precursors enter the developing CNS from the bloodstream, ventricles, and meninges. In the brain, these cells migrate and proliferate, as ameboid microglia, and become distributed throughout the nervous parenchyma. Ameboid microglial cells differentiate into ramified microglia when they reach their definitive location. The factors that control the invasion of the nervous parenchyma, migration, proliferation, and differentiation of microglial cells are not completely known. These important events may depend on environmental factors such as soluble or cell-surface-bound molecules and components of the extracellular matrix. In the developing CNS, microglial cells are involved in clearing cell debris and withdrawing transitory or misdirected axons, and presumably support neurogenesis, cell survival, and neurite growth. In the adult brain, activated microglia occur mostly in response to neuronal injuries, when, they destroy invading microorganisms, remove harmful debris, and promote tissue repair, as well as partaking in the immune response by secreting cytokines, facilitating the return to homeostasis. Microglial activation is an important event in the defense of the nervous parenchyma against infectious, neurodegenerative, and inflammatory diseases. The majority of data in the literature describes microglial cells in a neuropathological context. Little is known of the development of these cells in the nervous parenchyma and their effective role in neurogenesis.

We present the results of anopheline captures in Belém, Pará, Brazil, from 1995-2004, and a comparison with captures from 1930-1999. In the earlier period, 20 species were identified: Anopheles albitarsis s.l., An. aquasalis, An. argyritarsis, An. braziliensis, An. darlingi, An. eiseni, An. evansae, An. galvaoi, An. intermedius, An. kompi, An. mediopunctatus, An. nimbus, An. nuneztovari, An. oswaldoi, An. peryassui, An. punctimacula, An. shannoni, An. strodei, An. thomasi, and An. triannulatus. Seven of these species were not found in 1995-2004 (An. argyritarsis, An. eiseni, An. galvaoi, An. kompi, An. nimbus, An. punctimacula, and An. thomasi). The persistence of so many species is probably due to the local preservation of forest areas. Two species are of vectorial importance (An. darlingi and An. aquasalis). An. aquasalis is still the most abundant species (46.26% of adults, 99.21% of larvae) and the only one detected in all capture sites. There is thus a potential risk of malaria transmission in the entire municipality of Belém.

Connective-tissue growth factor (CTGF/CCN2) is a matricellular-secreted protein involved in complex processes such as wound healing, angiogenesis, fibrosis and metastasis, in the regulation of cell proliferation, migration and extracellular matrix remodeling. Glioblastoma (GBM) is the major malignant primary brain tumor and its adaptation to the central nervous system microenvironment requires the production and remodeling of the extracellular matrix. Previously, we published an in vitro approach to test if neurons can influence the expression of the GBM extracellular matrix. We demonstrated that neurons remodeled glioma cell laminin. The present study shows that neurons are also able to modulate CTGF expression in GBM. CTGF immnoreactivity and mRNA levels in GBM cells are dramatically decreased when these cells are co-cultured with neonatal neurons. As proof of particular neuron effects, neonatal neurons co-cultured onto GBM cells also inhibit the reporter luciferase activity under control of the CTGF promoter, suggesting inhibition at the transcription level. This inhibition seems to be contact-mediated, since conditioned media from embryonic or neonatal neurons do not affect CTGF expression in GBM cells. Furthermore, the inhibition of CTGF expression in GBM/neuronal co-cultures seems to affect the two main signaling pathways related to CTGF. We observed inhibition of TGFβ luciferase reporter assay; however phopho-SMAD2 levels did not change in these co-cultures. In addition levels of phospho-p44/42 MAPK were decreased in co-cultured GBM cells. Finally, in transwell migration assay, CTGF siRNA transfected GBM cells or GBM cells co-cultured with neurons showed a decrease in the migration rate compared to controls. Previous data regarding laminin and these results demonstrating that CTGF is down-regulated in GBM cells co-cultured with neonatal neurons points out an interesting view in the understanding of the tumor and cerebral microenvironment interactions and could open up new strategies as well as suggest a new target in GBM control.