Microfluidics: a new look at cell migration analysis

This thesis explores the development and employment of microfluidic devices as a tool for studying the effect of the surrounding environment on embryonic stem cells during the migration phenomena. Different single-cell microchips were designed and manufactured to study mouse embryonic fibroblasts (MEFs) migration towards an environmental variation (increase of serum concentration in the culture medium) that was expected to function as a motility stimuli. Considering the experimental, cells were injected into the microchips chambers and individually isolated by dedicated cell traps with view to a single-cell analysis. Once fribroblasts were attached to the surface, culture medium with an increased serum level was subsequently injected in an adjacent chamber to promote the formation of a serum concentration gradient. The gradient established between the chambers could be sensed by the fibroblasts and thus triggered the cells mobilization towards and in the direction of the richer serum medium. Additionally, the experiment allowed the observation of MEFs’ structural reorganization when migrating through micro-tunnels containing widths below the cell size, suggesting a cytoskeleton rearrangement on account of the nutritional stimulus introduced. Furthermore, results indicate that fibronectin promotes MEFs adhesion to the substrate and that MEFs migration is characterized as haptotactic.

Enhancing fan experience during live sports broadcasts through second screen applications

When sports fans attend live sports events, they usually engage in social experiences with friends, family members and other fans at the venue sharing the same affiliation. However, fans watching the same event through a live television broadcast end up not feeling so emotionally connected with the athletes and other fans as they would if they were watching it live, together with thousands of other fans. With this in mind, we seek to create mobile applications that deliver engaging social experiences involving remote fans watching live broadcasted sports events. Taking into account the growing use of mobile devices when watching TV broadcasts, these mobile applications explore the second screen concept, which allows users to interact with content that complements the TV broadcast. Within this context, we present a set of second screen application prototypes developed to test our concepts, the corresponding user studies and results, as well as suggestions on how to apply the prototypes’ concepts not only in different sports, but also during TV shows and electronic sports. Finally, we also present the challenges we faced and the guidelines we followed during the development and evaluation phases, which may give a considerable contribution to the development of future second screen applications for live broadcasted events.

Migration and mental health: Japanese Brazilians in Japan and in Brazil

OBJECTIVE: Brazil is the country with the largest community of Japanese descendants in the world, from a migration movement that started in 1908. However, more recently (1988), a movement in the opposite direction began. Many of these descendants went to Japan for work purposes and suffered mental distress. Some of them sought treatment in Japan, while others returned to Brazil to seek treatment. The aim of the present study was to compare the sociodemographic profile and diagnoses of Japanese Brazilian psychiatric outpatients in Japan (remaining group) and in Brazil (returning group). METHOD: All consecutive Japanese Brazilian outpatients who received care from the psychiatric units in Japan and Brazil from April 1997 to April 2000 were compared. The diagnoses were based on ICD-10 and were made by psychiatrists. Sociodemographic data and diagnoses in Brazil and Japan were compared by means of the Chi-Squared Test. RESULTS: The individuals who returned to Brazil were mostly male and unmarried, had lived alone in Japan, had stayed there for short periods and were classified in the schizophrenia group. The individuals who remained in Japan were mostly female and married, were living with family or friends, had stayed there for long periods and were classified in the anxiety group. Logistic regression showed that the most significant factors associated with the returning group were that they had lived alone and stayed for short periods (OR = 0.93 and 40.21, respectively). CONCLUSION: We conclude that living with a family and having a network of friends is very important for mental health in the context evaluated.

Targeting lactate transport suppresses in vivo breast tumour growth.

BACKGROUND Most cancers, including breast cancer, have high rates of glucose consumption, associated with lactate production, a process referred as "Warburg effect". Acidification of the tumour microenvironment by lactate extrusion, performed by lactate transporters (MCTs), is associated with higher cell proliferation, migration, invasion, angiogenesis and increased cell survival. Previously, we have described MCT1 up-regulation in breast carcinoma samples and demonstrated the importance of in vitro MCT inhibition. In this study, we performed siRNA knockdown of MCT1 and MCT4 in basal-like breast cancer cells in both normoxia and hypoxia conditions to validate the potential of lactate transport inhibition in breast cancer treatment. RESULTS The effect of MCT knockdown was evaluated on lactate efflux, proliferation, cell biomass, migration and invasion and induction of tumour xenografts in nude mice. MCT knockdown led to a decrease in in vitro tumour cell aggressiveness, with decreased lactate transport, cell proliferation, migration and invasion and, importantly, to an inhibition of in vivo tumour formation and growth. CONCLUSIONS This work supports MCTs as promising targets in cancer therapy, demonstrates the contribution of MCTs to cancer cell aggressiveness and, more importantly, shows, for the first time, the disruption of in vivo breast tumour growth by targeting lactate transport.

Patente farmacêutica: especificidades e tutela

Dissertação de mestrado em Direito dos Contratos e da Empresa

Untersuchungen zur Funktion der Proteinkinase B (PKB/Akt) bei der Migration und Adhäsion von Maus-Lymphozyten

Magdeburg, Universität, Diss., 2010

Der Einfluss von „Migration“ auf Belastungen und Bewältigungsstrategien von Kindern und Jugendlichen

Lautdem Migrationsmodell des amerikanischen Psychologen Carlos E. Sluzki handelt es sichbei Migrationen um generationsübergreifende Prozesse, die auf die nachfolgendenGenerationen eine belastende Wirkung haben. Diese Belastungen sind gemäß seiner Theorieauf kulturelle Unterschiede zwischen der Familie und der Mehrheitsgesellschaftzurückzuführen. Es gilt diese Theorie anhand folgender Fragestellungen empirisch zuuntersuchen: Gibt es einen Zusammenhang zwischen Belastungen und dem Migrationshintergrund? Werden Kulturunterschiede wahrgenommen? Wie werden Belastungen bewältigt?Die Ergebnisse dieser Untersuchung zeigen, dass der Migrationshintergrund nur geringfügigEinfluss auf Belastungen hat. Es wurde lediglich eine migrationsbedingte Belastung ermittelt,wobei es sich um Probleme beim bilingualen Spracherwerb handelt. Es wurden außerdemeine Reihe von Kulturunterschieden genannt, die nicht per se als Belastung erlebt werden,sondern auch als eine Bereicherung. Alle in der Untersuchung genannten Belastungen werdenunter Anwendung problemlösender oder emotionsregulierender Strategien bewältigt. Einebesondere Bedeutung ist dabei den vorhandenen sozialen Ressourcen beizumessen.Schlüsselwörter:Migration, Migrationshintergrund, Migrant_in, Migrationsmodell, Belastungen,problemlösende/emotionsregulierende Bewältigungsstrategien, persönliche/soziale Ressourcen,Kultur, Dichotomie, Mehrheitsgesellschaft, Wir/Sie - Gruppe, Untersuchung, Leitfaden,qualitative Inhaltsanalyse, Kategorien(system)

The American plant migration. The potato. / by Berthold Laufer, Late Curator, Dept. of Anthropology. Prepared for publication by C. Martin Wilbur, Curator, Chinese Archaeology and Ethnology.

v.28(1938)

Diel vertical migration of predators (planktivorous fish larvae) and prey (zooplankton) in a tropical lagoon

ABSTRACT Based on the hypothesis that diel vertical migration (DVM) is a mechanism of predator avoidance, the objective of the present study was to test for the occurrence of DVM in planktivorous fish larvae of Hypophthalmus edentatus (Spix, 1829) (Siluriformes, Pimelodidae) and Plagioscion squamosissimus (Heckel, 1840) (Perciformes, Sciaenidae), and zooplankton (rotifers, cladocerans and copepods) in an isolated tropical lagoon in the floodplain of the Upper Paraná River, Brazil (region of Parque Nacional de Ilha Grande). We investigated spatial overlap between predators (planktivorous fish larvae) and prey (zooplankton), and tested which physical and chemical variables of the water are related to the DVM of the studied communities. We performed nocturnal (8:00 pm and 4:00 am) and diurnal sampling (8:00 am and 4:00 pm) in the limnetic region of the lagoon for six consecutive months, from October 2010 to March 2011, which comprises the reproductive period of the fish species analyzed. During the day the larvae tried to remain aggregated in the bottom of the lagoon, whereas at night they tried to disperse in the water column. Especially for cladocerans, the diel vertical migration is an important behavior to avoid predation larvae of H. edentatus and P. squamosissimus once decreased spatial overlap between secured and its potential predators, which corroborates the hypothesis that DVM is a mechanism of predator avoidance. Although significant correlations were observed between the abiotic factors and WMD of microcrustaceans at certain times of day, the effect of predation of fish larvae on zooplankton showed more important in this environment, because the small depth and isolation not allow great variation of abiotic factors seasonally and between strata the lagoon.

Insulin secretion is regulated by the glucose-dependent production of islet beta cell macrophage migration inhibitory factor.

Macrophage migration inhibitory factor (MIF), originally identified as a cytokine secreted by T lymphocytes, was found recently to be both a pituitary hormone and a mediator released by immune cells in response to glucocorticoid stimulation. We report here that the insulin-secreting beta cell of the islets of Langerhans expresses MIF and that its production is regulated by glucose in a time- and concentration-dependent manner. MIF and insulin colocalize by immunocytochemistry within the secretory granules of the pancreatic islet beta cells, and once released, MIF appears to regulate insulin release in an autocrine fashion. In perifusion studies performed with isolated rat islets, immunoneutralization of MIF reduced the first and second phase of the glucose-induced insulin secretion response by 39% and 31%, respectively. Conversely, exogenously added recombinant MIF was found to potentiate insulin release. Constitutive expression of MIF antisense RNA in the insulin-secreting INS-1 cell line inhibited MIF protein synthesis and decreased significantly glucose-induced insulin release. MIF is therefore a glucose-dependent, islet cell product that regulates insulin secretion in a positive manner and may play an important role in carbohydrate metabolism.

Labor supply response to international migration and remittances in the Republic of Haiti

The Republic of Haiti is the prime international remittances recipient country in the Latin American and Caribbean (LAC) region relative to its gross domestic product (GDP). The downside of this observation may be that this country is also the first exporter of skilled workers in the world by population size. The present research uses a zero-altered negative binomial (with logit inflation) to model households' international migration decision process, and endogenous regressors' Amemiya Generalized Least Squares method (instrumental variable Tobit, IV-Tobit) to account for selectivity and endogeneity issues in assessing the impact of remittances on labor market outcomes. Results are in line with what has been found so far in this literature in terms of a decline of labor supply in the presence of remittances. However, the impact of international remittances does not seem to be important in determining recipient households' labor participation behavior, particularly for women.