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Local authority fiscal stance and the pattern of residential migration in the north west of England.

The degree of fiscal mobility present in household migration flows between local authority areas in northwestern England is assessed. Following an introduction, the paper is divided into three sections. "The first reviews the methodologies of previous attempts to assess the extent of fiscally induced migration, noting the dominance of American studies, and outlines a choice-theoretic structure within which it is possible to model human migration patterns. Section III considers the problems inherent in modelling migration flows, and Section IV presents results for a Compound Poisson analysis of migration between local authority areas within the four counties of the North West region of England, as well as an assessment of the prevalence of fiscal mobility."

Demography↗

Changing patterns of internal migration 1970-1990: a comparative analysis of Jews and whites in the United States.

Independently conducted yet complementary sets of data from the 1970/1971 and 1990 National Jewish Population Surveys and the U.S. censuses of the same years were used to analyze changes in the internal migration of Jews and whites during the periods 1965-1970(1971) and 1985-1990. Interstate lifetime and five-year migration rates among Jews increased to levels significantly surpassing those of whites. Adjusting Jewish migration rates for the educational achievement of their white counterparts did not have much of an effect on lifetime migration or on the recent migration of the 1970/1971 Jewish population; however, it accounted meaningfully for the migration propensities of Jews in the period 1985-1990. These findings suggest that socioeconomic status has begun to play a larger role in promoting different migration patterns than in promoting ethnic group differences. Further, the direction of Jewish migrations followed those of whites (i.e., from the North-east and Midwest to the South and West): and due to their higher migration rates, Jews have considerably narrowed the regional distribution differences between themselves and whites. I interpret these results as evidence of the weakening role of ethnicity in present-day America.

Acculturation↗

On the pattern of ameloblast migration.

The kinetics of ameloblast cells in continuously growing guinea pig molars were studied using autoradiography. The results showed that there was no direct relationship between ameloblast migration rate and ameloblast production rate, which indicated that ameloblasts actively migrated coronally. It was found that ameloblast migration rate was maximal at the root apex, and then reduced to a minimum value as the ameloblasts left their proliferative compartment and migrated coronally. A multiple regression model was found to be the most suitable one to represent the ameloblast migration pattern.

Ameloblasts↗

The impact of elite labour migration on the identification, selection and development of European soccer players.

In this study, we examined sociocultural aspects of the identification, selection and development of elite soccer players as part of wider processes of globalization, particularly worker migration. Patterns of migration were identified among the 704 players who comprised the national squads of the 32 nations contesting the finals of the 1998 World Cup in France. An analysis of the migration patterns within and between the six Confederations into which member nations of FIFA are grouped established the European Federation (UEFA) as soccer's core economy. The study is subsequently focused on Europe and, in particular, upon the import strategies of clubs in the four most popular destination countries - England, Germany, Italy and Spain. It is argued that, in light of European Union deregulation of worker migration between member states and, in particular, the Bosman judgement, European soccer is being reshaped. The identification and selection of elite players are producing migrant patterns that are seen increasingly to impact upon indigenous player development and, potentially, the viability and success of national teams. We argue that, although these developments are contoured in part by global economic factors, economic accounts alone do not provide an adequate understanding of them. A series of interrelated economic, political, cultural and social factors is at work. We conclude with a brief outline of the policy implications of the analysis.

Culture↗

The geography of AIDS: patterns of urban and rural migration.

We sought to describe the migration patterns of patients infected with the human immunodeficiency virus (HIV) who seek health services in North Carolina. Of 390 consecutive adult patients with HIV seen at one tertiary care medical center in the southeastern United States in the summer of 1990, 340 (87%) were approached, and 325 (83%) completed surveys. Thirty-seven percent of respondents thought they had been infected and 20% were told they were infected with HIV while living outside of North Carolina. One in five patients thought they had been infected while living in a rural county and more than half now live in rural communities (population of < 50,000). Sixty percent of patients had moved to North Carolina since 1980; 61% of these were North Carolina natives. Injecting drug users were more likely than those with other modes of exposure to HIV to have been diagnosed with HIV infection out of state (34% vs 18%). Patients' reasons for moving to North Carolina included social support (88%), health reasons (54%), and better work/educational opportunities (52%). We found that most patients with HIV who seek health care services in North Carolina live in rural areas with their families, and a substantial proportion migrated in after they were diagnosed out of state. Characterizing these migration patterns is crucial for predicting the diffusion of HIV to rural areas; designing AIDS prevention strategies, education, and health service needs; and assessing federal HIV care funding policies.

Acquired Immunodeficiency Syndrome↗

Proteome analysis of migrating versus nonmigrating rat heart endothelial cells reveals distinct expression patterns.

Migration of endothelial cells plays an important role during angiogenesis and the late remodeling phase of arteriogenesis. To investigate mechanisms responsible for cell migration, the authors subcloned a rat heart endothelial cell line (RHE) into a migrating and a nonmigrating cell line (RHE-A and RHE-neg, respectively). Both cell lines form cobblestone patterns in confluent cultures similar to the originating cell line, but RHE-neg cells grow in dense cell islets of several layers whereas RHE-A cells grow in a less dense monolayer. Both cell lines show the same expression pattern of known endothelial cell surface antigens (e.g., FIK-1). The authors used two-dimensional gel electrophoresis technique to look for differentially regulated proteins with possible functional importance for cell migration. The analysis of the cytosolic fraction as well as the membrane fraction revealed differences in the protein expression patterns of RHE-neg and RHE-A cells. Regulated spots were isolated and analyzed by mass spectrometry (MS/MS technique), leading to the identification of proteins potentially responsible for endothelial cell migration, e.g., the intermediate filament vimentin that was exclusively expressed in RHE-A cells. The authors thus have generated a reproducible model that allows the analysis of the proteome responsible for endothelial cell migration.

Animals↗

Migration dynamics and development in rural South Africa: demographic and socioeconomic perspectives.

"This paper addresses five key questions related to migration dynamics and development in rural South Africa: (1) Which individual and household level factors are particularly important in understanding migration patterns? (2) Taken together, are sociodemographic or socioeconomic factors more influential? (3) Do present patterns of migration and remittance flows reflect strategies that connote survival, or do they represent household efforts to advance their well-being and their position in society? (4) Which segments of the population appear to gain or lose from contemporary patterns of migration and remittance flows? and (5) How might remittances shape trends in local level development and equality, or inequality?... The data source is the nationwide representative sample survey ¿Project for Statistics on Living Standards and Development' undertaken in the latter part of 1993."

Africa↗

Migration and disease problems: a study of pattern of migration in an endemic area of malaria in Thailand.

The preliminary results of a study of rural-rural migration in an endemic area of malaria is reported. The study on socio-economic status of migrant workers was made during the post planting season of sugarcane plantation in Tambon Nong Rhee Kanchanaburi Province. Among 9,311 population in four villages of this Tambon, 15.4% were migrants and 45.5% were from the northeast provinces of Thailand. Almost half of the migrant population came to the area for the first time and stayed for six months mostly during the sugarcane cutting season. No significant difference in experience with malaria (as recognized by the people not from blood examination) between the local population and the migrants was observed from the interview. However, the duration of migration seemed to relate with the risk of contracting malaria.

Adolescent↗

Phosphorylation polymorphism in the yolk protein 2 of Drosophila hawaiiensis.

An intraspecific polymorphism in the electrophoretic migration pattern of the yolk proteins in D. hawaiiensis was established and characterized. The polymorphism includes yolk protein migration patterns of two, three, or four bands by polyacrylamide gel electrophoresis. Peptide mapping analysis demonstrates that in the two band migration pattern YP2 comigrates with YP3, whereas in the three and four band migration patterns YP2 migrates between YP1 and YP3 in addition to comigrating with YP3. It further demonstrates that the top two bands of the four band migration pattern consists of YP1. Phosphatase treatment of the yolk proteins establishes that the different electrophoretic migration patterns of YP2 are caused by different degrees of phosphorylation. It is suggested that the YP1 polymorphism is caused by a yp1 gene modification and that the YP2 polymorphism is caused by two different post-translational processing paths.

Journal Article↗

Not as the crow flies: a historical explanation for circuitous migration in Swainson's thrush (Catharus ustulatus).

Many migratory songbirds follow circuitous migratory routes instead of taking the shortest path between overwintering and breeding areas. Here, we study the migration patterns in Swainson's thrush (Catharus ustulatus), a neartic-neotropical migrant songbird, using molecular genetic approaches. This species is presently separated into genetically distinct coastal and continental populations that diverged during the Late Pleistocene (as indicated by molecular dating), yet appear to have retained ancestral patterns of migration. Low nucleotide diversity, a star-like haplotype phylogeny and unimodal mismatch distributions all support the hypothesis that both the coastal and the continental populations have undergone recent demographic expansions. Nearctic-neotropical banding and genetic data show nearly complete segregation of migratory routes and of overwintering locations: coastal populations migrate along the Pacific Coast to overwintering sites in Central America and Mexico, whereas continental populations migrate along an eastern route to overwintering sites in Panama and South America. Nearctic-neotropical banding data also show that continental birds north, northwest and east of this migratory divide fly thousands of miles east before turning south. We conclude that circuitous migration in the Swainson's thrush is an artefact of a Late Pleistocene range expansion.

Animal Migration↗

Mutational and methylation analysis of the cyclin-dependent kinase 4 inhibitor (p16INK4A) gene in chronic lymphocytic leukemia.

OBJECTIVES: Chronic lymphocytic leukemia (CLL) comprises a heterogeneous group of at least two types of disease entities characterized by distinctive clinical, immunophenotypical and genetic features. The molecular mechanisms underlying the pathogenesis and the histological transformation of CLL are not well known. The INK4A/p16, a cyclin dependent kinase inhibitor has been considered as a tumor suppressor gene. Inactivation of this gene by homozygous deletions, mutations and hypermethylation occurs in a variety of human neoplasms. The aim of the present study was to determine the frequency of p16 gene deletions and mutations as well as the methylation status of the same gene in CLL patients. METHODS: We examined 34 samples from CLL patients by Southern Blotting, Single-Strand Conformation Polymorphism (SSCP), DNA sequencing and Methylation-Specific PCR. RESULTS: Southern Blot analysis revealed non-rearranged bands in 33/34 cases. Homozygous deletions were not observed in any case. In 1/34 case a rearranged band was detected with EcoRI enzyme. The PCR-SSCP analysis of exons 1 and 3 revealed normal pattern of migration in all cases examined. The analysis of exon 2 revealed abnormal migration pattern in 2/34 cases (5.8%). Sequencing of these cases revealed the presence of the ALA148THR polymorphism. Methylation analysis of p16 gene promoter revealed hypermethylation of CpG islands in 6/34 cases (17.6%). CONCLUSION: These results indicate that genetic alterations of p16 gene are rare events in patients with CLL. The clarification of the role of p16 gene promoter methylation in the pathogenesis and evolution of CLL needs further investigation.

CpG Islands↗

A longitudinal radiographic study of the periosteal migration along the growing rabbit mandible.

In the present study, the role of the periosteum in mandibular growth was investigated. The orientation of the superficial bony spicules of rabbit mandibles was determined on dry skulls after perfusion of the animals with an India ink solution. The spicular orientation in the ramus area appeared to be toward the condyle, rostrally toward the incisors, and caudally toward the angular region. The behavior, during growth, of the periosteum in the caudal mandibular half was studied by implantation of metal periosteal and bone markers. A series of cephalograms revealed the migration pattern of the periosteal markers, and by that the migration pattern of the periosteum. It can be concluded that both the pattern of the superficial bony spicules and the periosteal migration pattern suggest a possible influence of the periosteum on mandibular growth.

Animals↗

In vitro-activated human lupus T cells express normal estrogen receptor proteins which bind to the estrogen response element.

We have shown that estrogen receptor (ERalpha, ERbeta) transcripts are expressed in SLE and normal T cells. In this study, T cell nuclear extracts from female lupus patients and normal donors were tested for biologically active ER proteins capable of binding to the human estrogen response element (hERE) by electrophoretic mobility shift assays. When peripheral blood T cells were stimulated with 17beta-estradiol (E2), PMA and ionomycin, two major retarded bands in T cell nuclear extracts exhibited a migration pattern similar to slow migrating protein-ERE complexes in human breast cancer cell extracts. T cells cultured only with E2 did not have these complexes. The formation of the complexes was inhibited by competition with the hERE cold oligonucleotide and partially with anti-ERalpha antibodies. There was no notable difference in the migration pattern of ERE-binding proteins between the SLE and normal T cell extracts. Together, these results suggest that activated human T cells, whether lupus-derived or normal-derived, contain biologically active ERalpha proteins. Other factors may be responsible for differential sensitivity of lupus T cells to estrogen.

Adult↗

Recombination and migration of Cryphonectria hypovirus 1 as inferred from gene genealogies and the coalescent.

Genealogy-based methods were used to estimate migration of the fungal virus Cryphonectria hypovirus 1 between vegetative compatibility types of the host fungus, Cryphonectria parasitica, as a means of estimating horizontal transmission within two host populations. Vegetative incompatibility is a self/non-self recognition system that inhibits virus transmission under laboratory conditions but its effect on transmission in nature has not been clearly demonstrated. Recombination within and among different loci in the virus genome restricted the genealogical analyses to haplotypes with common mutation and recombinational histories. The existence of recombination necessitated that we also use genealogical approaches that can take advantage of both the mutation and recombinational histories of the sample. Virus migration between populations was significantly restricted. In contrast, estimates of migration between vegetative compatibility types were relatively high within populations despite previous evidence that transmission in the laboratory was restricted. The discordance between laboratory estimates and migration estimates from natural populations highlights the challenges in estimating pathogen transmission rates. Genealogical analyses inferred migration patterns throughout the entire coalescent history of one viral region in natural populations and not just recent patterns of migration or laboratory transmission. This application of genealogical analyses provides markedly stronger inferences on overall transmission rates than laboratory estimates do.

Ascomycota↗

Rapid, simple method of preparing rotaviral double-stranded ribonucleic acid for analysis by polyacrylamide gel electrophoresis.

A procedure for extracting rotaviral double-stranded ribonucleic acid (RNA) directly from fecal and intestinal specimens collected from calves and pigs is described. This procedure provides a rapid, simple, reproducible method of obtaining rotaviral double-stranded RNA preparations suitable for electrophoretic analysis in polyacrylamide-agarose composite gels. The rotaviral genome electrophoretic migration pattern produced by double-stranded RNA extracted directly from a specimen by this procedure was qualitatively identical to the electrophoretic migration pattern obtained with double-stranded RNA extracted from purified rotavirus derived from the same specimen. Direct extraction of specimens containing porcine rotavirus-like virus by this procedure gave preparations that had electrophoretic migration patterns similar, but not identical, to the characteristic electrophoretic migration pattern of the rotaviral genome. Sufficient rotaviral double-stranded RNA could be extracted from 6 ml of fecal or intestinal specimen by this procedure to permit 15 or more electrophoretic assays.

Animals↗

Indigenous human cutaneous leishmaniasis caused by Leishmania tropica in Kenya.

Six Leishmania isolates from 3 indigenous Kenyans (2 isolates from one patient) and 2 Canadian visitors in Kenya were characterized by cellulose acetate electrophoresis. The isolates were compared among themselves and with reference strains of Leishmania donovani, L. aethiopica, L. major, L. tropica, and L. arabica using 9 enzymes: malate dehydrogenase (MDH), malic enzyme (ME), phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), aspartate aminotransferase (ASAT), adenylate kinase (AK), mannose phosphate isomerase (MPI), glucose phosphate isomerase (GPI), and phosphoglucomutase (PGM). Enzyme migration patterns of isolates from the 3 indigenous Kenyans were indistinguishable from those of 2 L. tropica reference strains. The isolates from the 2 Canadians yielded migration patterns of 7 enzymes that were indistinguishable from those of 2 L. tropica reference strains. However, migration patterns of 2 enzymes, PGM and ME, differed from all migration patterns of the 10 reference strains. Balb/c mice were inoculated with stationary phase promastigotes cultured from 3 stabilates from the lesions of 2 of the Kenyan patients. The mice developed no gross pathological lesions in 6 months time. All of the study patients developed cutaneous leishmaniasis while living in or visiting districts in Central and Rift Valley Provinces, Kenya. This is the first report of human cutaneous leishmaniasis caused by L. tropica indigenous to Africa south of the Sahara.

Adolescent↗

Loss of alternately spliced messenger RNA of the luteinizing hormone receptor and stability of the follicle-stimulating hormone receptor messenger RNA in granulosa cell tumors of the human ovary.

OBJECTIVES: The expression of messenger RNA (mRNA) for the LH (LHR) and FSH receptors (FSHR) was examined in normal human corpora lutea and granulosa cell tumors. METHODS: Expression was examined by RT/PCR and DNA sequencing techniques. RESULTS: The full-length (FL) coding region and seven additional isoforms were identified for normal LHR mRNA. Isoform 1 had portions of exons II and III deleted, and isoform 2 had exon IX omitted. Isoform 3 also had portions of exons II and III deleted and all of exon IX deleted. Exons III through VI were missing in isoforms 4-7. Isoform 5 also had exon IX omitted, and isoform 6 also had part of exon XI missing. Isoform 7 also had exon IX and part of exon XI deleted. An aberrant migration pattern of the LHR mRNA isoforms was observed for granulosa cell tumors with FIGO Stage I-IV. Five tumor samples of Stage III-IV had many isoforms absent. Seven Stage I samples had aberrant migration patterns that depended on the size of the tumor. As the size of the tumor increased the aberrant migration pattern of the LHR mRNA isoforms was more pronounced and some isoforms were not detected. The FL and at least one additional isoform were identified for FSHR mRNA. Isoform 1 had regions of exons IV and V deleted. The FSHR mRNA isoforms had a similar migration pattern for the normal ovary and the granulosa cell tumors. CONCLUSIONS: Alternately spliced forms of mRNA for the LHR and FSHR exist for normal human ovary and granulosa cell tumors. The aberrant migration and missing LHR mRNA isoforms in granulosa cell tumors do not appear to result from general genomic instability associated with tumor progression. These findings are important to understand the role of alternate splicing in the regulation of LHR and FSHR expression in different pathological states.

Alternative Splicing↗