Effects of the planetary migration on some primordial satellites of the outer planets

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Quantitative aspects of the migration and evolutive asynchronism of Schistosoma mansoni in mice

Two groups of white mice (Mus musculus) were infected with 65 and 440 cercariae transcutaneously. Migration of Schistosoma mansoni from skin to the lungs and to the portal system thereafter was studied through fitting mathematical equations. Six evolutive stages previously defined were used to determine the asynchronic development of parasites in the portal system. Equations the moment of maximum schistosomula recovery in skin and lungs. In the portal system the equations lead to different days of maximum recovery according to each stage. These differences measure quantitatively the asynchronism of S. mansoni.

Cytogenetic analysis of the Marsh Deer, Blastocerus dichotomus (Mammalia, Cervidae)

The chromosomic constitution of the Marsh Deer (Blastocerus dichotomus) was studied in 18 males and 18 females, mainly from the Tiete river basin in Sao Paulo State, Brazil. The species diploid number was determined to be 66 chromosomes and the fundamental number (FN), 74. The X and the Y were the largest and the smallest chromosome, respectively. Large amounts of the constitutive heterochromatin marked by the C band were located in the centromeric region of all the acrocentric chromosomes. The first chromosome pair was not marked and the second and third pairs showed weak centromeric markings. The X chromosome showed two strong telomeric markings while the Y was C band negative. Chromosomes four and five were the NOR carriers. Polymorphism for this band was observed in pair four. The results of this study are in agreement with other reports in the literature, in spite of the different origin of the animals.

Synergistic actions of 50°C water and imazalil dip treatments to preserve quality of late-season 'Marsh' grapefruit

Late-season grapefruits (Citrus paradisi Macf. cv. Marsh seedless) were dipped in water at 50°C for 3 min with and without 200 ppm imazalil (IMZ) or 1000 ppm IMZ at 19°C and were subsequently stored at 7°C and 90-95% relative humidity (RH) for 11 weeks plus one week at 21°C and approximately 75% RH to simulate a marketing period (SMP). Residue concentrations in fruit after treatment with 200 ppm IMZ at 50°C were 3.46 ppm, about twice the level (1.80 ppm) found in fruit treated with 1000 ppm IMZ at 19°C. Fungicide degradation rates during storage showed similar patterns resulting in an approximately 50% decrease. Both fungicide treatments significantly reduced decay and chilling injury (CI) during storage and SMP. Hot water reduced CI and decay but not as effectively as the IMZ treatments. Soluble solids concentrations were not affected by treatments, IMZ treatments resulted in significantly lower values of titratable acidity and higher concentrations of ethanol in the juice after SMP. Weight loss was significantly higher in fruit dipped in water at 50°C after SMP. No visible damage occurred to the fruit as a result of any of the treatments.

Ticks (Acari: Ixodidae) on Wild Marsh-Deer (Blastocerus dichotomus) from Southeast Brazil: Infestations before and after Habitat Loss

The lake from Porto-Primavera hydroelectric power station inundated an area of 2,200 km2 at the border of São Paulo and Mato-Grosso do Sul States, Brazil. Infestations by ticks were evaluated on 135 marsh deer, Blastocerus dichotomus (Illiger), captured before and after inundation. Ticks were collected for identification, and infestation level of animals was assessed by scoring. Deer were divided into four groups according to capture location and temporal relation to the inundation. Groups 1, 2, and 3 were captured before inundation. Group 4 was captured after inundation. Four tick species were found: Amblyomma cajennense (F.), Amblyomma triste Koch, Anocentor nitens (Neumann), and Boophilus microplus (Canestrini). Groups 1, 2, 3, and 4 had 30, 45, 100, and 96%, respectively, of animals carrying B. microplus ticks. A. triste was observed on 16, 22, 22, and 88% of animals from groups 1,2,3, and 4, respectively. A. nitens and A. cajennense were observed only on group 4, on 32 and 16% of the animals, respectively. Groups 1 and 2 had only 4.8 and 6.1% of animals with high infestation levels, respectively, and no ticks on 46.8% and 45.5% of the animals, respectively. Conversely, groups 3 and 4 lacked noninfested animals and had high infestation levels on 77.8 and 50% of deer, respectively. Marsh area shrinkage was blamed for higher infestation levels on deer from groups 3 and 4. The widespread presence of A. triste on marsh deer, a Neotropical tick species, raises the possibility of a natural host-parasite relationship.

Tuberculosis survey of free-ranging marsh deer (Blastocerus dichotomus) in Brazil

Esophageal-pharyngeal fluids from 53 free-ranging marsh deer (Blastocerus dichotomus) captured for a research program in the state of Mato Grosso do Sul, Brazil, were assayed for tuberculosis. Total DNA was extracted, amplified by polymerase chain reaction using specific primers for Mycobacterium tuberculosis complex (M. tuberculosis, M. bovis, M. microti, and M. africanum), and observed by agarose gel electrophoresis stained with ethidium bromide. All samples were negative. This, along with necropsy and histopathology data, suggests that these animals are not shedding and probably do not have active disease.

Periodontal conditions of teeth presenting pathologic migration.

The aim of the present study was to evaluate the periodontal conditions of anterior teeth that presented pathologic migration in patients with chronic periodontitis and to compare periodontal destruction in migrated versus non-migrated teeth. The sample included 32 patients of both sexes (mean age: 46.0 +/- 11.6 years) diagnosed with generalized chronic periodontitis and selected on the basis of the presence of pathologic migration in one or more anterior teeth. This migration was classified according to the following categories: facial flaring, diastema, proximal tilting, rotation or extrusion. The periodontal parameters recorded were clinical attachment loss (CAL) and percentage of radiographic bone loss (BL). Mean CAL of 5.50 +/- 2.20 mm and mean BL of 41.90 +/- 15.40% were found in 115 teeth assessed. The most frequent type of migration was facial flaring (34.80%), followed by diastema (27.00%). Extrusion was hardly observed in the sample (4.30%). However, greater severity of BL and CAL were observed in teeth with this type of migration (59.44% and 8.42 mm, respectively), and in teeth with facial flaring (45.17% of BL and 6.07 mm of CAL). Kruskal-Wallis test indicated that BL presented by teeth with extrusion or facial flaring was greater than that observed in rotated or tilted teeth (p < 0.05), while there was no difference between groups regarding CAL (p = 0.11). It was observed that anterior teeth with pathologic migration presented greater CAL and BL (5.1 mm and 40%) than non-migrated teeth (4.1 and 31%). The study indicated that the most prevalent kind of pathologic migration is facial flaring, which was associated to higher level of bone loss.

Vertical migration during tidal transport of megalopae of Necora puber in coastal shallow waters during daytime

For meroplanktonic larvae that must settle in coastal areas, their successful return to the shore is determined largely by physical transport processes; however, many organisms perform vertical movements to aid successful recruitment. In this study, daytime tidal vertical migration of megalopae of the velvet swimming crab Necora puber was investigated across two different exposures in the shallow waters of Plymouth Sound. Crabs were collected using a plankton net at the surface and near the bottom during flood and ebb tides. Distribution of the pelagic postlarvae was patchy and the abundance varied spatially in tens and thousands of metres. In temporal scales, the annual pattern was dominated by low occurrence of megalopae, punctuated by episodic peaks of high abundance. Most megalopae were collected at the surface irrespective of the tidal phase. The effect of wave exposure on the vertical migration of megalopae was not clear, although there was a general higher abundance of megalopae on exposed shores. Daytime abundance in the water column appears to be regulated by the tidal cycle, as megalopae were more abundant during flood than ebb tides. Although the megalopae do not appear to make large vertical migrations, this behaviour should produce a net shoreward transport. © 2005 Elsevier Ltd. All rights reserved.

Natural infection by Paramphistomoidea Stiles and Goldberger, 1910 trematodes in wild Marsh Deer (Blastocerus dichotomus Illiger, 1815) from Sérgio Mottas's hydroelectric power station flooding area.

Studies on helminthfauna of marsh deer Blastocerus dichotomus Illiger, 1815 are rare, although helminthic diseases are an important cause of mortality in these animals. Fifteen male and female adult marsh deer from Sergio Motta's hydroelectric power station flooding area at Paraná River which died during the capture and quarantine procedures, between 1998 and 1999, were necropsied. Three trematodes species, Paramphistomum cervi, Balanorchis anastrofus and Zygocotyle lunatum, all belonging to superfamily Paramphistomoidea, were identified. The obtained trematodes were identified, counted and their respectives descriptors of infection were determined. All necropsied animals were infected by helminths. Paramphistomum cervi was the most prevalent species, while Zygocotyle lunatum was found in only one animal.

A Harris-Todaro agent-based model to rural-urban migration

The Harris-Todaro model of the rural-urban migration process is revisited under an agent-based approach. The migration of the workers is interpreted as a process of social learning by imitation, formalized by a computational model. By simulating this model, we observe a transitional dynamics with continuous growth of the urban fraction of overall population toward an equilibrium. Such an equilibrium is characterized by stabilization of rural-urban expected wages differential (generalized Harris-Todaro equilibrium condition), urban concentration and urban unemployment. These classic results obtained originally by Harris and Todaro are emergent properties of our model.

Initial concentration profile influence on migration measurements from plastic packaging: A simulation study

Migration of components from plastic packaging into foodstuffs or into medicines is a very important issue, concerning public health. Using experimental techniques, like gas chromatography-mass spectrometry, these essays measure total migration and specific migration of components from plastic packaging. This work presents an explanation and applications of a numerical technique tool for this measurement, allowing the comprehension of the diffusion process and the estimate of component migration in difficult or impractical measurements. As an application example, the non-uniform influence of initial concentration profile on the migration is presented, demonstrating the necessity of this profile determination for high quality considerations on involved metrology.

Transferability of microsatellite loci from Cervidae species to the endangered Brazilian marsh deer, Blastocerus dichotomus

Blastocerus dichotomus, the marsh deer, is the largest Brazilian Cervidae species. The species is endangered because of hunting and loss of its natural habitat, i.e., flood plain areas, because of hydroelectric power station construction and agricultural land expansion. In the present study, we tested 38 microsatellite loci from four Cervidae species: Odocoileus virginianus (7), Rangifer tarandus (17), Capreolus capreolus (7), and Mazama bororo (7). Eleven loci showed clear amplification, opening a new perspective for the generation of fundamental population genetic data for devising conservation strategies for B. dichotomus. © FUNPEC-RP.

Neutrophil migration induced by IL-1β depends upon LTB4 released by macrophages and upon TNF-α and IL-1β released by mast cells

In the present study, we investigate whether mast cells and macrophages are involved in the control of IL-1β-induced neutrophil migration, as well as the participation of chemotactic mediators. IL-1β induced a dose-dependent neutrophil migration to the peritoneal cavity of rats which depends on LTB 4, PAF and cytokines, since the animal treatment with inhibitors of these mediators (MK 886, PCA 4248 and dexamethasone respectively) inhibited IL-1β-induced neutrophil migration. The neutrophil migration induced by IL-1β is dependent on mast cells and macrophages, since depletion of mast cells reduced the process whereas the increase of macrophage population enhanced the migration. Moreover, mast cells or macrophages stimulated with IL-1β released a neutrophil chemotactic factor, which mimicked the neutrophil migration induced by IL-1β. The chemotactic activity of the supernatant of IL-1β-stimulated macrophages is due to the presence of LTB4, since MK 886 inhibited its release. Moreover, the chemotactic activity of IL-1β-stimulated mast cells supernatant is due to the presence of IL-1β and TNF-α, since antibodies against these cytokines inhibited its activity. Furthermore, significant amounts of these cytokines were detected in the supernatant. In conclusion, our results suggest that neutrophil migration induced by IL-1β depends upon LTB4 released by macrophages and upon IL-1β and TNFα released by mast cells. © 2007 Springer Science+Business Media, LLC.

Development, institutional and policy aspects of international migration between Africa, Europe and Latin America and the Caribbean

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