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Results for “Migration patterns”

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PubMedDate not supplied

Longitudinal analysis of internal migration to La Paz, Bolivia.

"This study examines the migration patterns of Bolivians who have moved from other provinces to La Paz. In order to better understand these patterns, the capital city was divided into eight similar socio-economic regions and the migration patterns analyzed for selected regions. In addition, the study compares the migrant flows for two time periods: location at the time of birth, and the migrant's residence in 1971. The research analyzes statistically the differences between migration fields for a representative area."

Americas↗

PubMed1995

L3T4(CD4)-, Lyt-2(CD8)- and Mac-1(CD11b)-phenotypic leukocytes in murine cryptococcal meningoencephalitis.

An immunohistological study of L3T4(CD4)+ and LYT-2(CD8)+ lymphocytes, Mac-1(CD11b)+ monocytes and granulocytes in experimental murine cryptococcal meningoencephalitis was conducted. To assess the concomitant inflammatory reaction in an extracerebral site, livers were examined in parallel. Mice were infected i.v. with Cryptococcus neoformans, group A/D, and organs were examined immunohistologically for CD4-, CD8- and monocyte- and granulocyte-specific CD11b-phenotypic leukocytes over a period of 60 days. Intracerebrally, agglomerations of cryptococci formed pseudocysts that were surrounded by CD4+ and CD8+ lymphocytes at the end of the second week post-infection, followed by the invasion of monocytes and granulocytes into the lesions. After the fourth week post-infection, most of the invaded lesions were transformed into glious scars. Meningitis was usually marked and showed a homogenous distribution of CD4-, CD8- and CD11b-phenotypic cells, with a predominance of monocytes and CD4+ lymphocytes. Inflammatory infiltrates in the liver were found already 4 days post-infection. CD4+ lymphocytes and monocytes were distributed homogeneously in the infiltrates, with a lower number of CD8+ lymphocytes being located rather in the periphery of the infiltrates. Comparing leukocyte kinetics in brain and liver, an important observation was the delayed immigration of immune cells at the intracerebral cryptococcal lesions as compared with the liver, and the different migration patterns of T-lymphocyte subgroups and macrophages. These results suggest that there are differential leukocyte migration patterns in the liver and brain following disseminated cryptococcosis. The immunological aspects of the observed leukocyte kinetics are discussed.

Animals↗

PubMedDate not supplied

[Presence of Triatoma infestans in relation to various cultural patterns in a rural population of the Province of San Juan, Argentina].

This paper reports results from a punctual epidemiological survey performed in San Juan, at Bermejo, a rural village located 100 km east from the provincial capital, in December 1987. The village had been rebuilt after almost complete destruction by an earthquake, in 1977. According to a census performed by local Primary Health Care Agents, there were 82 households, where 72 (88%) of them were inhabited, with a total human population of 198 people. Forty-eight from those inhabited dwellings (67%) were visited, and a general questionnaire was completed. Information gathered included, sex, age, working activity, number of people and domestic animals at the house, construction patterns of houses and outdoor premises, resting habits of animals, specially dogs, domestic use of insecticides and migration patterns of inhabitants. A timed collection of triatomines (man-hour method) was undertaken in 17 out of 48 of the visited households. Sampled triatomines were kept and classified by collection site, instar, and sex at the field. Species identification, microscopical examination of fecal contents to detect trypanosomes and blood-meals identification, were performed at the laboratory. Sixty-nine per cent (33/48) of the dwellings were "ranchos" with mud-brick ("adobe") and cane walls, roofs made of cane and mud dirt floors. The remainder were as follows: 11 (23%), partially improved houses and 4 (8%) had brick walls and were tiled or had zinc roofs. Data of migration patterns of local population were obtained in 31 (65%) out of 48 households. Seasonal movements within San Juan Province, mainly related to vintage were reported in 20/31 (65%) families.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1995

Antibody transformation by peroxynitrite as determined using capillary electrophoresis: a feasibility study.

Peroxynitrite may be a physiologically relevant endogenous neurotoxin that forms following CNS trauma when excessive levels of NO and .O2 accumulate. Recently, peroxynitrite was found to inactivate the polyclonal antibody to cAMP. A feasibility study was performed to evaluate the use of capillary electrophoresis as an effective tool regarding the structural transformation of antibody following exposure to peroxynitrite with or without co-incubation with a peroxynitrite scavenger. A polyclonal antibody to cAMP and a monoclonal antibody to plasminogen activation inhibitor-1 were exposed to peroxynitrite with or without penicillamine coincubation. Samples were analyzed by an Applied Biosystems analytical capillary electrophoresis system, model 270A. Initial examination of the peroxynitrite scavenger penicillamine and its reaction with peroxynitrite showed a penicillamine migration peak at about 9.1 min and a presumed s-nitro adduct of penicillamine that migrated at 10.9 min. Exposure of either antibody to peroxynitrite resulted in structural transformation of protein based on changes in migration patterns. In addition, co-incubation with penicillamine prevented this transformation and preserved the pre-peroxynitrite migration patterns of antibodies. In cases of antibody reaction, s-nitro adduct formation could be simultaneously monitored. We found capillary electrophoresis to be ideally suited to this type of analysis. With capillary electrophoresis, we were able to simultaneously monitor the effects of peroxynitrite on large proteins and a small scavenger molecule. As a result, a complete record of the reaction was obtained within a single 15-min analysis period.

Antibodies↗

PubMed1988

Glial fiber pattern in the developing chicken cerebellum: vimentin and glial fibrillary acidic protein (GFAP) immunostaining.

The possible relation between glial fibers and the formation of longitudinal granule cell migration patterns that occur in the cerebellar anlage of the chicken was investigated by immunocytochemistry of vimentin (monoclonal antibody) and glial fibrillary acidic protein (polyclonal antibody against GFAP, PGF) on fixed and unfixed brain tissues. In addition, neuronal development was studied with a monoclonal antibody for neurofilament. Vimentin was present in radial and tangential fibers in the cerebellar anlage during granule cell migration in almost all parts of the anlage. However, no specific topographic relation of vimentin and GFAP to the migration pattern of granule cells was observed. In adults, Bergmann fibers and astroglia were stained with vimentin antiserum and not with GFAP antiserum. Conclusions are that radial fibers do not determine the formation of longitudinal cytoarchitectonic patterns in the chick cerebellum and that vimentin is the main cytoskeletal component of Bergmann fibers and astroglial cells in embryonic and adult chicken cerebellum.

Animals↗

PubMed1986

Molecular epidemiology of rotavirus infections in Uppsala, Sweden, 1981: disappearance of a predominant electropherotype.

The molecular epidemiology of rotavirus infections was studied in children with acute gastroenteritis in Uppsala, Sweden, during 1981. Altogether 118 virus strains were investigated by analysis of the RNA migration pattern in silver-stained polyacrylamide gels. Six different electropherotypes were seen: two with "short" and four with "long" RNA migration patterns. Forty-two strains (36%) exhibited "short" patterns. The seasonal distribution showed that strains with "long" and "short" RNA patterns cocirculated in equal frequency during the first seven months of the year, until the predominant "short" RNA electropherotype suddenly disappeared. More than 11 RNA segments were seen in two stool specimens. A complete correlation was found between the electrophoretic migration of segments 10 and 11 and the serological defined subgroup specificity.

Adolescent↗

PubMed2003

A preliminary hip joint simulator study of the migration of a cemented femoral stem.

A hip joint simulator that can be used to evaluate the outcome of the cemented total hip replacement has been designed, manufactured and evaluated. The simulator produces motion of a cemented hip construct in the extension/flexion plane, with a socket to rotate internal/externally. At the same time a dynamic loading cycle is applied to the construct. A validation test was performed on a cemented femoral stem within a novel composite femur. The study demonstrates the value of using a hip joint simulator to evaluate the outcome of the cemented hip construct. A complex migration pattern of the cemented hip prosthesis with respect to load cycling was observed, demonstrated in vitro comparable prosthesis migration behaviour, both the stem migration and migration patterns, to that found clinically.

Cementation↗

PubMed1990

Subgroup classification of porcine group-A rotaviruses, using monoclonal antibodies in an enzyme-linked immunosorbent assay.

Fifty-six samples of feces and intestinal contents from nonvaccinated diarrheal pigs with rotavirus infections were tested, using a subgroup (SGP)-specific ELISA, to determine rotavirus SGP classification. Forty-one percent (23/56) were SGP 1, 25% (14/56) were SGP 2, and 34% (19/56) were not classifiable. For classifiable samples, the geographic distribution for SGP 1 and SGP 2, respectively was: 60%/40% from Ohio (n = 15), 63%/37% from other midwestern states (Iowa, Minnesota, Nebraska, South Dakota; n = 16), and 67%/33% from Canada (n = 6). Thirty-seven SGP-classifiable samples were categorized according to age of pigs. Of pigs less than or equal to 1 week old, 22% of samples were SGP 1 (n = 8), and 14% (n = 5) were SGP 2. Of samples from 1- to 2-week-old pigs, 8% were SGP 1 (n = 3), and 5% were SGP 2 (n = 2). Of samples from 2- to 3-week-old pigs, 5% were SGP 1 (n = 2), and 8% were SGP 2 (n = 3). Of samples from 3- to 4-week-old pigs, 5% were SGP 1 (n = 2), and 3% were SGP 2 (n = 1). Of samples from pigs greater than 4 weeks old, 22% were SGP 1 (n = 8) and 8% were SGP 2 (n = 3). Double-stranded RNA extracted from positive controls and from 10 selected field samples (5 from SGP 1 and 5 from SGP 2) was electrophoresed in polyacrylamide gels to detect correlation between subgroup classification by ELISA and long or short double-stranded RNA electrophoretic-migration patterns. All SGP-1 and -2 rotavirus samples tested had typical long double-stranded RNA electrophoretic-migration patterns.

Age Factors↗

PubMed1999

The Caenorhabditis elegans gene ham-2 links Hox patterning to migration of the HSN motor neuron.

The Caenorhabditis elegans HSN motor neurons permit genetic analysis of neuronal development at single-cell resolution. The egl-5 Hox gene, which patterns the posterior of the embryo, is required for both early (embryonic) and late (larval) development of the HSN. Here we show that ham-2 encodes a zinc finger protein that acts downstream of egl-5 to direct HSN cell migration, an early differentiation event. We also demonstrate that the EGL-43 zinc finger protein, also required for HSN migration, is expressed in the HSN specifically during its migration. In an egl-5 mutant background, the HSN still expresses EGL-43, but expression is no longer down-regulated at the end of the cell's migration. Finally, we find a new role in early HSN differentiation for UNC-86, a POU homeodomain transcription factor shown previously to act downstream of egl-5 in the regulation of late HSN differentiation. In an unc-86; ham-2 double mutant the HSNs are defective in EGL-43 down-regulation, an egl-5-like phenotype that is absent in either single mutant. Thus, in the HSN, a Hox gene, egl-5, regulates cell fate by activating the transcription of genes encoding the transcription factors HAM-2 and UNC-86 that in turn individually control some differentiation events and combinatorially affect others.

Amino Acid Sequence↗

PubMedDate not supplied

Primary isolation and identification of avian rotaviruses from turkeys exhibiting signs of clinical enteritis in a continuous MA 104 cell line.

Avian rotaviruses were isolated from turkeys with enteritis using MA 104 cell line. MA 104 cells were suitable for primary isolation and propagation of avian rotaviruses. Trypsin appeared essential for the enhancement of infectivity and the occurrence of cytopathic effect (CPE). Serum neutralization (SN), electron microscopy (EM), and analysis of genomic RNA were done to identify and confirm the identity of rotaviruses. Electrophoretic migration patterns of genomic RNA from avian rotaviruses were examined, and they were compared with those from mammalian rotaviruses. The migration patterns differed between these groups.

Animals↗

PubMed1984

The changing structure of nonmetropolitan migration in the American Deep South.

"The United States and other post-industrial societies have recently undergone a form of population deconcentration characterized as rural-urban 'population turnaround'. This phenomenon may be attributed to changes in internal migration patterns. Explanations for such changes frequently imply that they have been accompanied by changes in the structure, or determinants, of migration. This study examines that thesis for a specific region, the American Deep South, for the 1950-1978 time period." The results suggest "that a structural transformation has occurred. During the 1950s, a decade of heavy net emigration, nonmetropolitan migration patterns were closely linked to the patterning of sustenance activity and metropolitan accessibility. By the 1970s, such linkages had weakened considerably. But this structural transformation can be detected in some parts of the region in the 1960s. Elsewhere, it still had not occurred in the 1970s."

Alabama↗

PubMed2006

Migration and cyclic motion of a new short-stemmed hip prosthesis--a biomechanical in vitro study.

BACKGROUND: Uncemented, short-stemmed hip prostheses have been developed to reduce the risk of stress shielding and to preserve femural bone stock. The long-term success of these implants is yet uncertain. Prerequisite for osseointegration is sufficient primary stability. In this study the cyclic motion and migration patterns of a new short-stemmed hip implant were compared with those for two clinically successful shaft prostheses. METHODS: The prostheses were implanted in paired fresh human femura and loaded dynamically (gait cycle) with increasing load (max 2,100 N) up to 15,000 cycles. Relative displacements between prosthesis and bone were recorded using a 3D-video analysis system. FINDINGS: The short stem displayed a biphasic migration pattern with stabilisation at maximum load. Initial migration was predominantly into varus and was greater than that for the shaft prostheses. Failure occurred in cases of poor bone quality and malpositioning. Cyclic motion of the short prosthesis was less than that for the shaft prostheses. Surface finish showed no effect. System stiffness for the new stem was lower than for the shaft prostheses. INTERPRETATION: The new stem tended to migrate initially more than the shaft prostheses, but stabilised when cortical contact was achieved or the cancellous bone was compacted sufficiently. Bone quality and correct positioning were important factors for the short stem. The lower cyclic motion of the new stem should be favourable for bony ingrowth. The lower system bending stiffness with the new implant indicated a more physiological loading of the bone and should thereby reduce the effects of stress shielding.

Adult↗

PubMed2004

Long-lasting donor passenger leukocytes after hepatic and intestinal transplantation in rats.

BACKGROUND: Donor passenger leukocytes (DPLs) that migrate after organ transplantation stimulate the recipient immune system and normally cause rejection and graft vs. host reaction. However, DPLs also contribute to the unresponsiveness to the donor organ. The quantity and quality of these migrating cells are considered dependent on individual transplanted organs. We compared the DPLs of the liver, which might contain somatic stem cells, with those of intestinal grafts that have highly immunogenetic cells. To study DPLs over a long period, we used green fluorescent protein (GFP) transgenic (Tg) rats developed by us as donors. METHODS: We performed orthotopic liver transplantation (OLT) and small bowel transplantation (SBT) from GFP Tg rats to wild recipients. A short course of tacrolimus (0.64 mg/kg, intramuscularly) was used to prevent antigenicity of the GFP. The fate of the DPLs in the peripheral blood and the recipient bone marrow was monitored by flow cytometry. Using long-surviving recipients, the GFP(+) cells in the graft and various host immunologic organs were measured and characterized by immunohistochemical staining. RESULTS: In both groups, the numbers of the GFP(+) cells in the peripheral blood increased transiently and then gradually decreased to undetectable levels. While no GFP(+) cells were identified in the long-surviving-recipient bone marrow, there were a few GFP(+) cells in the graft liver, graft mesenteric lymph nodes and the recipient spleen. These cells showed major histocompatibility complex (MHC) class II antigen. There was no significant difference in the migration patterns of the GFP(+) cells in the OLT and SBT rats. CONCLUSIONS: In both the OLT and SBT groups, the DPLs migrated transiently in the recipient peripheral blood. A small numbers of MHC class II-positive DPLs were present at the graft site and in the host spleen, but not in the bone marrow. There were no significant differences in the migration patterns of the DPLs between the OLT and SBT rats over the long term.

Animals↗

PubMed2003

The role of Grg4 in tectal laminar formation.

Mature chick optic tecta consist of 16 laminae and receive retinal fiber projections in a precise retinotopic manner. Retinal axons arborize in laminae a-f of the SGFS, but do not cross the border between lamina f and g. In order to elucidate molecular mechanisms of tectal laminar formation, we first looked at the migration of tectal postmitotic cells. We found that the migration pattern of postmitotic cells changes around E5 and that late migratory cells intervened laminae that were formed by early migratory cells. The coincident appearance of Grg4 expression in the tectal ventricular layer and the change in migration pattern suggested an important role for Grg4. Clonal misexpression of Grg4 resulted in cells migrating to laminae h-j of the SGFS. Massive misexpression of Grg4 resulted in disruption of laminae that were formed by early migratory cells, in particular lamina g of the SGFS. Application of Grg4 morpholino antisense oligonucleotide or the misexpression of a dominant-negative form of Grg4 exerted the opposite effect. We concluded that Grg4 may direct tectal postmitotic cells to follow a late migratory pathway.

Animals↗

PubMed1983

In vivo migration of 111In radiolabeled mouse-spleen lymphocytes and tumor cells.

Mouse-spleen lymphocytes, mouse mammary adenocarcinoma cells (MMA-67) and mouse lymphoma cells (S49.1) were radiolabeled with 111In and their in vivo migration patterns studied over a 24-72 h period after i.v. injection into syngeneic mice. All three cell lines showed different in vivo migration patterns. Initially, some trapping of the cells occurred in the lungs at 15 min. More MMA-67 cells were initially trapped in the lungs than S49.1 cells or lymphocytes. At 24 h, most of the 111In labeled cells had left the lungs and accumulated in various tissues and organs. At 48 and 72 h, only slight changes in the localization patterns of the 111In radiolabeled cells in vivo were noted when compared to the 24 h patterns. About 35% of the injected 111In was excreted from the animals over the 72 h period of these experiments. In vitro studies compared the growth and/or viability of 111In radiolabeled lymphocytes or tumor cells to nonradiolabeled lymphocytes or tumor cells. The percentage of 111In released from the cells in culture was also determined. Similar values for growth and/or viability were obtained between non-radiolabeled cells and MMA-67 cells radiolabeled with 1.35 dpm 111In per cell; S49.1 cells, 0.51 dpm111In per cell; and lymphocytes, 0.04 dpm 111In per cell.

Adenocarcinoma↗

PubMed1996

Internal migration of the foreign-born in Canada.

"This article uses the Public Use Sample file of the 1986 Canadian census to characterize and explain the interprovincial migration patterns of the foreign-born in Canada. Simple overall in- and outmigration rates are calculated for the foreign-born and compared to the interprovincial migration rates for Canadian-born migrants, specifically primary, return and onward migrants. A two-level nested logit model is then applied for foreign-born migrants age 20-64 to study the effects of personal factors and provincial attributes on their interprovincial migration patterns. The foreign-born have higher in- and outmigration rates than primary migrants, with Ontario having a strong ability to attract and retain the foreign-born. Despite these differences, the foreign-born respond to economic variables in a rational way and relatively little of the migration decision process can be explained by place-of-birth effects. Selectivity with respect to personal factors (i.e., education, age, sex, family type) is similar to the Canadian-born."

Americas↗

PubMed1989

In vivo localization of lymphocytes labelled with low concentrations of Hoechst 33342.

Hoechst 33342 (HO 33342) is a fluorescent dye which binds specifically to DNA and can be used to label lymphocytes for in vivo migration studies. Lymphocytes were treated with varying concentrations of HO 33342 and assayed in vitro for effects on viability, mitogen-stimulated proliferation, and motility. In vivo traffic studies were performed to determine a dye concentration with minimal toxicity for lymphocytes, but sufficient fluorescence for detection of cells in frozen sections. The concentration reported to yield quantitative staining of nuclear DNA (10.7 microM, or 6 micrograms/ml) reduced motility and proliferative response, and resulted in an altered lymphocyte migration pattern compared to untreated lymphocytes. A concentration of 0.25 microM, however, produced no toxicity in the in vitro assays, and an in vivo migration pattern similar to that of untreated cells; lymphocytes stained with 0.25 microM HO 33342 for 30 min were readily observable in histological sections. This study indicates that the concentration of HO 33342 optimal for DNA staining may exert deleterious effects on in vivo lymphocyte traffic studies, and that far lower dye concentrations are more suitable for such studies.

Animals↗

PubMed1995

Denaturing gradient gel electrophoresis analysis for the detection of point mutations in the Chlamydia trachomatis major outer-membrane protein gene.

Fifty clinical strains of Chlamydia trachomatis were studied by denaturing gradient gel electrophoresis (DGGE) of bacterial DNA amplified by the polymerase chain reaction (PCR). The strains belonged to the three most commonly encountered serovars in developed countries--D, E and F. Six reference strains, including the serovar Da strain, were also studied. The DNA sequences explored encompassed the four variable domains (VDs) of omp1, the gene encoding the major outer-membrane protein (MOMP). The corresponding regions in the MOMP contain the species-, subspecies- and serovar-specific epitopes. The four distinct serovars were clearly differentiated by specific migration pattern. No sequence variations were observed among strains of serovar F. However, variant strains within serovars D and E were found, which exhibited migration patterns different from those of the reference strains and these were sequenced directly. According to the observed sequence variations, serovar D strains could be divided into three stable representative groups (D, D1 and D2). Two variants were identified among serovar E strains. No biological differences were observed for the variant strains in terms of growth properties, ecology or pathogenicity. All the nucleotide substitutions detected in the VDs were non-synonymous at the protein level and, for the serovar D strains, could account for differences identified by specific monoclonal antibodies. These substitutions could be involved in antigenic drift, driven by the immune pressure of the host, leading to the emergence of serovariants. The data may explain, in part, chlamydial infection recurrences and could have critical implications for developing rational vaccine strategies.

Algorithms↗