Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Migration patterns”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,477 records · Page 82Linked to original sources
PubMed2000

Integration of epithelial patterning and morphogenesis in Drosophila ovarian follicle cells.

Drosophila oogenesis involves the coordinated development of germ cells and an overlying follicular epithelium. The follicle cells provide a genetically tractable system to investigate the cell biology of patterning and morphogenesis. Follicle cells initially form a cuboidal epithelium surrounding a syncytium of nurse cells and oocyte. Epithelial structure is maintained as these cells reorganize to create the three dimensional architecture of the eggshell. Both long-range and short-range cell-cell communications pattern the domains of follicle cells that will create specific eggshell structures. After terminal differentiation to deposit the eggshell proteins, the follicle cells die. This review summarizes recent progress in understanding the cell-cell communication that orchestrates follicle cell patterning and migrations. DE-cadherin-mediated adhesion is important at several steps in egg chamber formation and follicle cell migration. Notch signaling is critical during each successive round of patterning and migration. Integration of bone morphogenetic protein (BMP) and epidermal growth factor (EGF) signals patterns the elaborate structures of the dorsal-anterior eggshell.

Animals↗
PubMed1986

Biological aspects of Amazonian fishes--VI. Hemoglobins and whole blood properties of Semaprochilodus species (Prochilodontidae) at two phases of migration.

Electrophoretic patterns of hemoglobins, red blood cell phosphates, Bohr effect of blood and stripped hemoglobin, ATP and GTP modulation of Hb-O2 affinity of two species belonging to the genus Semaprochilodus (S. insignis and S. taeniurus--jaraquis), captured at two different locations in Rio Negro, near Manaus (Amazonas), are described. High Bohr effect values were found in these two species and in jaraqui-açu (a possible hybrid between them). In S. insignis a higher Bohr effect for migrating individuals was observed, while S. taeniurus showed the reverse. The main erythrocytic phosphates found in these two species are ATP and GTP. They have a large influence on the O2-Hb binding properties in both species. The GTP/ATP ratio showed large differences between catching places. The two species have different electrophoretic patterns. Semaprochilodus insignis showed four anodal components which showed quantitative variation between catching places; S. taeniurus had three anodal components and a similar quantitative variation.

Animals↗
PubMed1992

Migration of 75Se-methionine-labeled Schistosoma japonicum in normal and immunized mice.

The patterns of migration and attrition of Schistosoma japonicum larvae were studied in a mouse model. Control and immunized mice were challenged with 100 S. japonicum cercariae tagged with 75Se-labeled methionine. Skin, lungs, liver, and other organs were analyzed by compressed organ autoradiography for the presence of larvae that appeared as reduced silver foci. The pattern of migration of S. japonicum was similar in mice with primary infection and in mice immunized with irradiated cercariae. Skin was not a site of attrition after primary infection nor after immunization. Attrition occurred after migration to the lungs and continued until after migration to the liver in mice with primary infection, while in immunized mice attrition occurred before lung migration and continued at a faster rate than in normal mice. In both control and immunized mice, the lungs and liver were the major sites of attrition.

Animals↗
PubMed1999

Different patterns of abnormal neuronal migration in the cerebral cortex of mice prenatally exposed to irradiation.

A characteristic abnormal cortical architecture in the adult brain was produced in mice subjected to 1.5 Gy of X-irradiation on embryonic day 14. Neurons in the lateral regions were organized into an essentially six-layered structure, while neurons in the dorsal regions formed a unique four-layered cortex. The patterns of neuronal migration in these different cortical regions were examined with immunohistochemistry for anti-bromodeoxyuridine (BrdU), anti-midkine (MK), and anti-glial fibrillary acidic protein (GFAP) antibodies. In the cortical lateral region, BrdU-labeled cells in the upper layers were fewer, and those in lower layers more numerous in prenatally irradiated mice than in control, while in the dorsal region (four-layered region), BrdU-labeled cells were very few in layer 2, and a large number of labeled-cells remained in layer 4. These results indicated that some neuroblasts in the lateral cortical region could not migrate to the upper layers, and that most neuroblasts in the dorsal cortical region failed to pass through the earlier migration zone. MK- and GFAP-stained radial glial fibers showed that the radial fibers were consistently oriented in the direction of neuronal migration in the control brains. However, in the irradiated brain, such radial fibers were crumpled in the lateral region, or were reduced markedly in number in some parts of the dorsal region. These results revealed that neuronal migratory pathways (radial glial fibers) were destroyed differently in different regions, and that X-rays killed some cells including radial glial cells or their precursors during the embryonic stage. These effects of radiation on the developing brain may result from the possibility that neurogenetic time is different or there are cellular mechanisms involved in the radiosensitivity among different regions.

Animals↗
PubMed1993

Grafting of fast blue labeled glial cells into neonatal rat brain: differential survival and migration among cell types.

Cultures of oligodendrocyte progenitor cells, ERD 1.1 cells, a nontransformed immortalized cell line of oligodendrocyte progenitors and C6 glioma cells were labeled with the fluorescent dye Fast Blue and transplanted into brains of 4 day postnatal Wistar rat pups. The localization of fluorescent cells within host brain was examined at various times post-transplantation to determine patterns of cell migration as well as survival and integration among the host tissue. Oligodendrocyte progenitors migrated mainly along white matter tracks, integrating successfully into the host parenchyma. High survival rates were found between 5 and 27 days post grafting. ERD 1.1 cells survived and migrated between 1 and 5 days after transplantation. However, by 27 days survival had dropped from 60 to 20% of the initial cell population. The surviving cells were mainly localized to subventricular and subependymal regions at 27 days. C6 cells migrated extensively rostrally and caudally from the site of injection in the hippocampus and were tumorogenic. This finding confirmed previous reports on the survival and migration patterns of oligodendrocyte progenitors grafted into neonatal brain. However, they show that two cell lines that share phenotypic properties of oligodendrocyte progenitors markedly differ from these cells with respect to migration patterns and integration within host parenchyma. Fast Blue dye was still detectable after repeated cell division in grafted C6 cells, enabling us to track single cells as well as tumor formation. This dye should be useful not only to address issues of development, but also of tumor biology and therapeutic treatment.

Amidines↗
PubMed1981

Patterns of cell proliferation and cell migration in the Sézary syndrome.

The patterns of cell proliferation and cell migration were studied in three patients with the Sezary syndrome using autoradiographic techniques. Cell labeling patterns following pulse labeling with tritiated thymidine in vivo indicated that Sezary cells proliferate actively in skin and in lymph nodes but that few if any Sezary cells proliferate in the peripheral blood. In two of the patients serial samples were obtained. Label dilution patterns in skin and blood over time suggested that circulating Sezary cells originated in extracutaneous sites where cells were proliferating more rapidly than in the skin. Cells labeled in extracutaneous sites of proliferation appear rapidly in the blood, and their transit time through the peripheral blood compartment is short. Circulating Sezary cells may then be deposited in the skin where they resume proliferation at a low rate. Thus, while Sezary cells proliferate in both cutaneous and extracutaneous sites, proliferation appears to be more rapid in extracutaneous sites such as lymph nodes. This suggests that trials of systemic therapeutic approaches should be undertaken.

Autoradiography↗
PubMed1999

Stability assessment of a moderately conforming all-polyethylene tibial component in total knee arthroplasty: a prospective RSA study with 2 years of follow-up of the Kinemax Plus design.

The magnitude and pattern of the migration of an all-polyethylene tibial component with moderately conforming articular surfaces in total knee arthroplasty was analyzed in 20 patients > or =60 years during a 2-year follow-up using radiostereometry (RSA). Most of the migration occurred during the initial 4 months, whereafter the migration diminished, reaching a mean maximum migration of 0.75 mm at 2 years. Similar patterns were found for rotation of the implant. Maximum subsidence at 2 years was 0.7 mm and was most commonly located at the posteromedial part of the tibial component. These results indicate that an all-polyethylene tibial component with moderately conforming articular geometry and with a thickness of 10-12 mm demonstrated migration patterns compatible with a favorable prognosis in regard to future aseptic loosening.

Aged↗