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PubMed1984

Distribution of radiolabelled lymph cells in lymph nodes and the migratory properties of blood lymphocytes in sheep.

The results found in this study supported the concept of lymphocyte populations with preferential migratory pathways. Preferential localization of lymphocytes in lymph nodes could not explain the non-random lymphocyte migration patterns observed in sheep. The migration of lymphocytes isolated from the blood was similar to that of lymphocytes in the efferent lymph of a subcutaneous lymph node, but was different from the migration of lymphocytes isolated from efferent intestinal lymph. The subcutaneous lymph node did not need to be selective for lymphocytes which entered from blood. However, there must be a selective entry of a population of lymphocytes with preference for migrating through mesenteric lymph nodes into efferent intestinal lymph in order to observe the differential lymphocyte migration patterns exhibited by the lymphocytes in the efferent intestinal lymph of sheep.

Animals↗

PubMed1991

Modulation of B cell maturation and migration to the thymus of SJL mice. B cell migration to the thymus.

The direct linkage of the B cell maturation process and infiltration of the thymus with mature B cells was studied in SJL mice. Phenotypically and functionally, B cells in the thymus of old SJL mice are mature B cells; IgM+, IgD+, Ly-1-, and evince a high proliferative response to lipopolysaccharide and a low one to dextran sulphate. Memory B cells can be found in the thymus of mice immunized with T-dependent or T-independent antigens. Chronic depletion and B cell maturation arrest induced by fractionated total lymphoid irradiation or by neonatal splenectomy eliminate B cells from the thymus and block their migration from the periphery to the thymus. When examined in adoptive transfer experiments, thymus B cells were found to possess a normal migration pattern and homing receptors; their migration pattern did not differ from that of lymph node or splenic B cells. It is evident, therefore, that the large number of normal functioning B cells in the thymus of SJL mice reflects a massive infiltration of the thymus by mature B cells from the periphery due to thymus dysfunction rather than to an abnormal in situ differentiation of intrathymic B cell precursors.

Animals↗

PubMed1987

Patterns of disease in localized extranodal lymphomas.

The site of origin of lymphoid tissue is an important determinant of lymphocyte migration patterns. The association of gastrointestinal (GI) and Waldeyer's ring lymphoma and the unique lymphocyte migration pattern of gut-associated lymphoid tissue (GALT) have been previously described. To establish whether predictive clinical patterns of disease occur in localized Non-Hodgkin's lymphoma, survival and relapse patterns for 496 patients with stage I and II non-Hodgkin's lymphoma (NHL) treated with loco-regional irradiation (XRT) alone were examined. We identified 139 patients with GALT lymphoma (defined as arising from primitive gut and including Waldeyers' ring, thyroid, and GI lymphomas) and 87 patients with extranodal non-gut-associated lymphoma (ENL). Survival and relapse data were assessed in multifactorial analysis to correct for previously identified other prognostic variables. GALT lymphomas (GALT-L) have a survival advantage compared with other ENL (P = .017) independent of stage and histology. A difference in distant relapse (DR) rate between GALT-L and other ENL (P = .0002) was also identified. The presentation site of localized extranodal NHL is predictive of clinical behavior and is an independent determinant of outcome. This may be an expression of lymphocytic origin and determinants of migration patterns.

Abdominal Neoplasms↗

PubMed1982

Polymorphism of genomic RNAs within rotavirus serotypes and subgroups.

The genome of human rotaviruses is composed of 11 segments of double stranded RNA. Analysis by polyacrylamide gel electrophoresis of the genomic RNA from a number of strains of the same serotype has demonstrated a significant polymorphism in the migration pattern. However, two strains differing from each other in serotype were found to have apparently identical RNA migration patterns. It is concluded that serotype cannot be deduced from RNA migration patterns. Degrees of polymorphism have been observed within each of three known human rotavirus serotypes.

Electrophoresis, Polyacrylamide Gel↗

PubMed1993

[Epidemiology of rotavirus infantile diarrhea in Istanbul using virus genome RNA electrophoresis].

Rotaviruses were detected using ELISA and latex agglutination, in 210 of 826 (25.4%) stool specimens collected from children with gastroenteritis between October 1984 and August 1990. In 82 of the 85 specimens (96%), Rotavirus specific RNA pattern was detected with polyacrylamide gel electrophoresis and silver staining. In 44 of the 56 strains with long migration pattern, 20 different electropherotypes and in 25 of the 26 strains with short migration pattern, 9 different electropherotypes were seen, respectively. Of the remaining strains, 3 were accepted as having mixed RNA pattern since 15 or 16 bands were detected in electrophoresis and 2 strains (one from long; one from short migration pattern) showed an extra RNA band.

Diarrhea, Infantile↗

PubMed1988

Molecular epidemiology of human rotavirus infections based on genome segment variations in viral strains.

Molecular epidemiology of rotavirus infections in 621 hospitalized children was investigated by analysis of migration patterns of viral genomic ribonucleic acid (RNA) segments by electrophoresis in polyacrylamide gels. Based on migration patterns of RNA segments of 184 rotavirus strains, seven different electropherotypes were identified: 146 (79.3%) strains were "long," and 38 (20.7%) were "short" electropherotypes; 61% belonged to a single dominant "long" electropherotype, which persisted throughout the 15-month period of study, whereas six other cocirculating types appeared at varying intervals. Electrophoretic migration patterns of RNA from viral isolates of two patients suggested mixed infections with different rotaviruses. There was a lack of correlation between the electrophoretic migration of segments 10 and 11 and serologically defined subgroup specificity in three of the rotavirus strains. Rotavirus infections and different electropherotypes were observed throughout the year.

Child, Preschool↗

PubMed2004

Electrophoretic variants of cardiac myosin heavy chain-alpha in Sprague Dawley rats.

Analysis of cardiac myosin revealed differences in gel electrophoretic migration patterns of the alpha-isoform of myosin heavy chain, but not the beta-isoform, in Sprague Dawley rats. No differences in the migration patterns of the alpha-or beta-isoforms were observed in other rat strains. Three electrophoretic migration patterns of the alpha-isoforms were observed in individual rats: a slower migrating isoform alone (4% of all rats tested), a faster migrating isoform alone (55%), and both isoforms (41%). The isoform expression pattern was identical in all myocardial regions in each rat. Frequency of expression patterns suggests multiple gene sequences for alpha-cardiac myosin heavy chain in Sprague Dawley rats. Sequence analysis of amplified regions of the Sprague Dawley and Brown Norway rat alpha-myosin genes, specifically the 5'-untranslated region, exons 1-3, and associated introns, showed numerous single nucleotide polymorphisms in coding and noncoding regions, including putative regulatory sites in Sprague Dawley rats, but not in Brown Norway rats. All Sprague Dawley rats varied from Brown Norway rats and no heterogeneity was observed in Brown Norway rats. Several deletions and dimorphic positions were also observed. Dimorphic positions were evident on automated sequencing comparisons. The data indicate that at least two alpha-myosin heavy chain isoforms exist in Sprague Dawley rats and these rats exhibit sequence diversity within that portion of the alpha-myosin heavy chain gene reported in this study.

Animals↗

PubMed2005

16S rDNA PCR-denaturing gradient gel electrophoresis in determining proportions of coexisting Actinobacillus actinomycetemcomitans strains.

Certain serotypes of Actinobacillus actinomycetemcomitans seem to prefer coexistence in vivo. The 16S rDNA PCR-denaturing gradient gel electrophoresis (DGGE) was tested for its capability to distinguish coexisting A. actinomycetemcomitans strains of different serotypes or genetic lineages and to determine their proportions in vitro. The migration pattern of the PCR amplicon from serotype c differed from those of the other serotypes. Contrary to the strains of serotypes c, d, and e, strains of serotypes a, b, and f consistently demonstrated intra-serotype migration patterns similar to each other. Since the migration patterns differed between serotype c and b strains a strain of each was used to determine their proportional representation in a strain mixture. The strains were distinguishable from each other above the 5% PCR-DGGE detection level (12.5 ng DNA/1.5 x 10(6) cells). DGGE provides a promising tool for in vitro studies on the coexistence of different genetic lineages of A. actinomycetemcomitans.

Aggregatibacter actinomycetemcomitans↗

PubMed1997

[Discovery of a novel reassortant H1N2 influenza virus].

Three strains of influenza A virus were isolated from patients suffering from influenza like disease in Railway Hygiene and Anti-epidemic Station of Taiyuan in January 1996. The identification results by serological method indicated that the isolates were different from H1N2 subtype of influenza A virus isolated from men in 1989 and 1992 and that their HA antigenicity was similar to that of A/RP/8/34 (H1N1) virus, but distinguishable from that of influenza A (H1N1) virus circulating in mans recently. The comparison of migration patterns of the RNA among the isolates, the A/PR//34 (H1N1) and the A/Wuhan/359/95 (H3N2) viruses revealed that the migration patterns of RNA 1-4 segments of the isolates were similar to those of A/PR/8/34 (H1N1) virus, but those of RNA 5-6 segments were indistinguishable from those of A/Wuhan/359/95 (H3N2) strain. However, the migration patterns of RNA 7-8 segments of the isolates were not only different from those of A/PR/8/34 (H1N1) virus, but also distingrasgable from those of A/Wuhan/359/95 (H3N2) strain. Therefore, it could be considered that the isolates were a novel reassortant H1N2 influenza A virus.

Adolescent↗

PubMed1975

Patterns of migration of the femoral head in osteoarthritis of the hip. Roentgenographic-pathologic correlation and comparison with rheumatoid arthritis.

Characteristic roentgenographic patterns of femoral head migration occur in osteoarthritis of the hip. In a study of 100 patients superolateral migration was noted in 15, superomedial in 48, superior migration of intermediate type in 15, and medial displacement of the femoral head in 22. Correlation with pathologic specimens obtained following total hip replacements and comparison with patterns of femoral head migration in rheumatoid arthritis were accomplished. It would appear that anatomic features of the acetabulum are of prime importance in the determination of the type of femoral head displacement complicating osteoarthritis.

Acetabulum↗

PubMed1982

Polymorphism of the migration of double-stranded RNA genome segments of avian reoviruses.

A number of field isolates of avian reovirus were characterized by analysis of the migration pattern of their genomic double-stranded RNA (dsRNA) segments upon polyacrylamide gel electrophoresis. Comparison of the various isolates has demonstrated (i) no relationship between serotype and migration of any individual dsRNA segment, (ii) marked polymorphism of migration patterns of all dsRNA segments among isolates of the same serotype as well as among different serotypes, (iii) no correlation between genotype and disease state, (iv) less marked variability in migration pattern from isolates within a restricted geographic locale compared to isolates from distant locales, (v) the presence of a single genotype in local outbreaks of disease, and (vi) the relative invariant migration of several dsRNA segments among the avian reoviruses, one of which (S1) may serve to distinguish the avian from the mammalian reoviruses.

Animals↗

PubMed2002

Comparison of gene expression patterns and migration capability at quiescent and proliferating vascular smooth muscle cells stimulated by cytokines.

The changes of the gene expression patterns and the migration capability of vascular smooth muscle cells (VSMC) at the quiescent and proliferating states were investigated after VSMC was stimulated by cytokines. VSMC migration was measured using a model of wounding injury of confluent cultured cells and a Boyden chamber assay. The migration distance of the quiescent VSMC induced by cytokines bFGF, IL-1beta and TNF-alpha was 5.8, 4.7, and 4.2 times as long as that of the control group, respectively. However, the migration distance of the proliferating VSMC was only one-fourth of the quiescent cells under the same effects. The results of Boyden chamber assay indicated that VSMC was capable of degrading collagen and traversed the pores of membrane barriers in response to bFGF as a chemoattractant, and VSMC number across the membrane was markedly increased as concentration gradient of bFGF ascended. Northern blot and nuclear run-off assay showed that bFGF not only stimulated the expression of migration-related matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) but also enhanced the transcription of proliferation-related osteopontin (OPN) and c-jun genes in the quiescent VSMC. bFGF could moderately increase the expression of OPN and c-jun, but had no significant effect on the expression of MMP-2 and TIMP-2 in the proliferating cells under the same conditions. These findings suggest that VSMC migration capability and the expression activity of migration- and proliferation-related genes were significantly distinct for the quiescent and proliferating VSMC. The cellular migration capability and the expression activity of migration-related genes in the quiescent VSMC were much higher than those in the proliferating cells in response to cytokines.

Animals↗

PubMed1991

Black retirement migration in the United States.

The specific aim of this study was to extend the analysis of retirement migration patterns to older Blacks. The 1980 Census public use sample A provided the data for this analysis. Because of their strong initial southern settlement and their labor force out-migration patterns in this century, many older Black migrants are "provincial return migrants" to the South, a migrant type that may decline among Blacks in the future. There is also a regional counterstream migration pattern among older Black migrants. Out-migrants in this stream from the South have elevated indicators of dependency. Suggestions are made for other related studies of Black retirement migration.

Black or African American↗

PubMed1997

Migration of host and donor T cells in small bowel transplantation.

In this study migration of host and donor CD4+ and CD8+ T cells in a fully allogeneic model was described and compared with the migration pattern in a graft-versus-host reaction (GVHR) model, where the T-cell traffic in the graft served as a physiological control. Heterotopic small bowel transplantations were performed in a rat model, with animals being sacrificed on postoperative days (POD) 2, 3, 4, 5, and 7. Graft and host mesenteric lymph nodes were harvested, homogenized, and stained with monoclonal antibodies against MHC class I, CD4+, and CD8+ antigens. The host and donor T cell migration patterns were studied using a double-staining flow cytometric technique. We found that during the development of rejection, the normal physiological circulation of graft and host T cells was disrupted. In the graft of the allogeneic model, a shift from host cell to graft cell dominance occurred on POD 3-4. This change in migration pattern coincided in the host with a 6% peak in graft cell infiltration, which disappeared on POD 7. These patterns of T-cell migration may be further explored for diagnostic purposes.

Animals↗

PubMed2005

Mutations in GPIIIa molecule as a cause for Glanzmann thrombasthenia in Indian patients.

BACKGROUND: Glanzmann thrombasthenia (GT) results from a quantitative or qualitative defect of GPIIb-IIIa complex, the fibrinogen receptor on platelets, which plays a very important role in platelet aggregation. In this report we describe the molecular studies on 22 patients with Glanzmann Thrombasthenia at our institute. OBJECTIVES: The main objective was to identify the mutations present in our GT population in order to establish a strategy for genetic counseling and antenatal diagnosis. METHODS: Twenty-two patients with GT were included in the present study. Complete blood count (CBC), platelet aggregation, flow cytometry, Western blot, single strand conformation polymorphism (SSCP) and denaturing gradient gel electrophoresis (DGGE) were performed in all the patients. The patients showing an abnormal migration pattern in SSCP or DGGE were sequenced further on an automated sequencer. RESULTS: Of the 22 patients studied, mutations were detected in 12 individuals. Of these, 11 were novel mutations and one mutation Y115C was reported earlier. Flow cytometric analysis showed the absence of receptors in type I GT, highly reduced levels in type II GT and normal levels in type III GT. The DGGE analysis and SSCP analysis of the patients showed different migration patterns. Sequencing was performed in all patients showing an abnormal migration pattern. Of the 22 cases studied mutations could be detected in 12 cases of GT. We could detect six patients with point mutations, four patients with insertions and five patients with deletion mutations. Exon 4 has been found to be the most common site for mutations in our patients. CONCLUSION: This study has shown a wide array of mutations present in our GT patients which would be extremely useful in genetic counseling and prenatal diagnosis, essential in preventing these disorders in succeeding generations.

DNA Mutational Analysis↗

PubMed1993

Spatial and space-time correlations in systems of subpopulations with genetic drift and migration.

The geographic distribution of genetic variation is an important theoretical and experimental component of population genetics. Previous characterizations of genetic structure of populations have used measures of spatial variance and spatial correlations. Yet a full understanding of the causes and consequences of spatial structure requires complete characterization of the underlying space-time system. This paper examines important interactions between processes and spatial structure in systems of subpopulations with migration and drift, by analyzing correlations of gene frequencies over space and time. We develop methods for studying important features of the complete set of space-time correlations of gene frequencies for the first time in population genetics. These methods also provide a new alternative for studying the purely spatial correlations and the variance, for models with general spatial dimensionalities and migration patterns. These results are obtained by employing theorems, previously unused in population genetics, for space-time autoregressive (STAR) stochastic spatial time series. We include results on systems with subpopulation interactions that have time delay lags (temporal orders) greater than one. We use the space-time correlation structure to develop novel estimators for migration rates that are based on space-time data (samples collected over space and time) rather than on purely spatial data, for real systems. We examine the space-time and spatial correlations for some specific stepping stone migration models. One focus is on the effects of anisotropic migration rates. Partial space-time correlation coefficients can be used for identifying migration patterns. Using STAR models, the spatial, space-time, and partial space-time correlations together provide a framework with an unprecedented level of detail for characterizing, predicting and contrasting space-time theoretical distributions of gene frequencies, and for identifying features such as the pattern of migration and estimating migration rates in experimental studies of genetic variation over space and time.

Biometry↗

PubMed2002

Electropherotypes of rotaviral RNA from cases of infantile diarrhea in Uruguay.

Electropherotypes of human rotavirus isolates from infants with acute diarrhea belonging to two populations with different clinical features were determined. Thirteen electropherotypes were identified in total 69 isolates; 46 (66.6%) isolates had long RNA migration patterns and 23 (33.3%) isolates had short migration pattern. One of the long-pattern electropherotypes (47.82% of the total electropherotypes) was predominant. It was detected in both populations almost throughout the whole period of the study, while other electropherotypes were found only occasionally. The co-circulation of long and short electropherotypes was not frequent.

Diarrhea, Infantile↗

PubMed2005

Meta-ecosystems and biological energy transport from ocean to coast: the ecological importance of herring migration.

Ecosystems are not closed, but receive resource subsidies from other ecosystems. Energy, material and organisms are moved between systems by physical vectors, but migrating animals also transport resources between systems. We report on large scale energy transport from ocean to coast by a migrating fish population, the Norwegian spring-spawning (NSS) herring Clupea harengus. We observe a rapid body mass increase during parts of the annual, oceanic feeding migration and we use a bioenergetics model to quantify energy consumption. The model predicts strong seasonal variation in food consumption with a marked peak in late May to July. The copepod Calanus finmarchicus is the most important prey and 23 x 10(6) tones (wet weight) of C. finmarchicus is consumed annually. The annual consumption-biomass ratio is 5.2. During the feeding migration 17% of consumed energy is converted to body mass. The biomass transported to the coast and left as reproductive output is estimated from gonad weight and is about 1.3 x 10(6) tones for the current population. This transport is to our knowledge the world's largest flux of energy caused by a single population. We demonstrate marked temporal variation in transport during the last century and discuss the effects of NSS herring in the ocean, as a major consumer, and at the coast, where eggs and larvae are important for coastal predators. In particular, we suggest that the rapid decline of lobster Homarus gammarus landings in Western Norway during the 1960s was related to the collapse of NSS herring. We also discuss spatial variation in energy transport caused by changed migration patterns. Both climate and fisheries probably triggered historical changes in the migration patterns of NSS herring. New migration routes emerge at the level of individuals, which in turn determines where resources are gathered and delivered, and therefore, how meta-ecosystems function.

Animal Migration↗