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PubMed1991

Characterization of seminoma-derived placental-like alkaline phosphatase.

Characteristics of placental-like alkaline phosphatase (PLAP-like enzyme) in seminoma was studied. By use of lectin affinity chromatography, PLAP-like enzyme in seminoma revealed extra sugar chains compared to placental alkaline phosphatase (PLAP), indicating heterogeneity of the carbohydrate moiety. However, the glycosylation patterns were found to be essentially similar between seminoma and normal testis. On isoelectric focusing, differences in migration patterns were revealed between seminoma-derived and normal testis-derived PLAP-like enzyme as well as between PLAP-like enzyme and PLAP. The differences in charge were mainly due to differences in sialylation of the molecules. The complex pattern of PLAP-like enzyme from seminoma on isoelectric focusing was not altered by neuraminidase treatment, indicating a considerable charge heterogeneity within the population of the enzyme molecules from the tumor.

Alkaline Phosphatase↗
PubMed1975

The different migratory characteristics of lymphocyte populations from a whole spleen transplant.

Spleens from AS x BN donor rats labelled in vivo by multiple doses of [3H]thymidine were transplanted into syngeneic recipients by anastomosis to the abdominal great vessels. The recipients were killed 1-5 days after receiving the whole spleen transplants and the numbers and location of the [3H]thymidine-labelled cells which had migrated from the labelled donor spleen traced by means of autoradiographs of sections, imprints and smears of various recipient lymphoid tissues. These results were compared with the migration pattern of labelled dissociated spleen cell suspensions injected intravenously. The latter consists almost entirely of small lymphocytes which migrate to T or B areas of recipient spleen, lymph nodes and Peyer's patches. The labelled whole spleens also contained cells which migrated to the T and B areas of recipient lymphoid tissues, but in addition contained many lymphoid cells which migrated to the red pulp of the recipient spleen and to the lamina propria of the gut. These experiments showed, therefore, that the spleen contains mobile elements which have not been detected by transfer of spleen cell suspensions.

Animals↗
PubMed1992

Analysis of genetic variation of epizootic hemorrhagic disease virus and bluetongue virus field isolates by coelectrophoresis of their double-stranded RNA.

Thirty-two bovine field isolates of bluetongue virus (BTV), 6 field isolates of epizootic hemorrhagic disease virus (EHDV) from deer, 4 BTV prototype serotypes (10, 11, 13, and 17), and 2 EHDV prototype serotypes (1 and 2) were coelectrophoresed, using polyacrylamide gels. Field isolates were obtained from various regions of the United States. Analysis of polyacrylamide gels and scattered plots generated for comparison of migration patterns for different isolates within each serotype of BTV revealed wide variation among the individual segments. The BTV serotypes 10 and 11 had more variation, compared with BTV serotypes 13 and 17, especially for migration of genome segment 5. A definitive correlation was not seen between the double-stranded RNA migration profiles on polyacrylamide gel electrophoresis, geographic origin, herd of origin, or year of collection. One BTV field isolate contained more than 1 electropherotype, with 2 bands at the segment-7 position, and it was further characterized as BTV serotype 11. Segments 2 and 5 of EHDV isolates were more variable in their migration than were the other gene segments. Generally, migration profiles for EHDV double-stranded RNA were more variable, compared with those of BTV isolates. Although a correlation was found between migration profiles and serotype of 2 isolates of EHDV, a study of additional EHDV isolates is required before the diversity of electrophoretic patterns of EHDV can be determined.

Animals↗
PubMed1991

Generation of avian cells resembling osteoclasts from mononuclear phagocytes.

Several lines of indirect evidence suggest that a monocyte family precursor gives rise to the osteoclast, although this hypothesis is controversial. Starting with a uniform population of nonspecific esterase positive, tartrate-sensitive, acid phosphatase-producing, mannose receptor-bearing mononuclear cells, prepared from dispersed marrow of calcium-deprived laying hens by cell density separation and selective cellular adherence, we generated multinucleated cells in vitro. When cultured with devitalized bone, these cells show, by electron microscopy, the characteristic osteoclast morphology in that they are mitochondria-rich, multinucleated, and, most importantly, develop characteristic ruffled membranes at the matrix attachment site. Moreover, as documented by scanning electron microscopy, these cells pit bone slices in a manner identical to freshly isolated osteoclasts. In addition, isoenzymes of acid phosphatase from generated osteoclasts, separated by 7.5% polyacrylamide gel electrophoresis at pH 4, are identical to those of mature osteoclasts in migration pattern and tartrate resistance, although the precursor cells from which the osteoclasts are generated produce an entirely different isoenzyme, which is tartrate-sensitive and migrates less rapidly at pH 4. The fused cells also exhibit a cAMP response to prostaglandin E2. Therefore, osteoclast-like cells can be derived by in vitro culture of a marrow-derived monocyte cell population.

Animals↗
PubMed1990

In vivo migration and tissue localization of highly purified lymphokine-activated killer cells (A-LAK cells) in tumor-bearing rats.

Our laboratory has previously reported that the adoptive transfer of highly purified lymphokine-activated killer cells (adherent-LAK, A-LAK) into Fischer 344 (F344) rats bearing established lung or liver micrometastases effectively reduced the resultant tumor growth more than 90%, leading to significant increases in animal survival (Cancer Res. 49, 1441, 1989). To begin to investigate the mechanism(s) by which A-LAK cells mediate this anti-tumor effect, we studied their migration patterns in F344 rats bearing experimentally induced lung and liver metastases as well as subcutaneous tumors. A-LAK cells which were phenotypically 95 to 100% natural killer cells/large granular lymphocytes were labeled with either 51Chromium or fluorescein diacetate (so as to be visualized microscopically). Intravenous injection of such labeled A-LAK cells did not show significant differences in their tissue distribution patterns in tumor-bearing versus normal rats, even when high levels of exogenous recombinant interleukin-2 (rIL-2) was administered. A-LAK cells first migrated to the lungs and then subsequently migrated to the liver and spleen as early as 2 to 6 hr following iv injection. The kinetics of exit of A-LAK cells from the pulmonary capillary beds was not significantly different in rats bearing 3-day micrometastases or 14-day macrometastases compared to normal rats. Moreover, the presence of metastases in the liver did not alter the extent or kinetics of entry of A-LAK cells into the liver even in the presence of exogenously administered rIL-2. Finally, in rats bearing subcutaneous tumors, no evidence could be obtained that A-LAK cells were selectively localized to the tumor site. Tissue sections of livers from metastases-bearing animals injected with fluorescein diacetate labeled A-LAK cells did not demonstrate significant numbers of A-LAK cells infiltrating tumor nests with or without the administration of exogenous IL-2. These data suggest that A-LAK cells may mediate tumor regression in vivo by direct and indirect mechanisms, possibly through the secretion of cytokines and/or the recruitment of secondary effector cells.

Adenocarcinoma↗
PubMed1989

[Transplantation of embryonic cerebella into adult rat cerebella].

Cerebellar primordia of rat embryos (embryonic days of 14-20) were transplanted into mature cerebella of normal adult rats (Fischer 344). After 1-12 months, animals were sacrificed, and the development of grafts and the interaction between host and graft were examined by light and electron microscopy. Grafts from E14 rat cerebella showed the highest survival rate (85%), which decreased with increasing donor age. In some experiments, the donor tissue developed and differentiated to form folia with the trilaminar organization of the cerebellar cortex. Synaptic connections between neuronal elements in the graft showed basically the normal pattern. Thus, mossy terminals formed synaptic contacts with dendrites of granule cells, and axons of basket cells made synaptic contacts with somata of Purkinje cells. Many spines of Purkinje dendrites were contacted with parallel fibers, while others were surrounded by processes of astroglia. Migration of donor Purkinje and granule cells in the host molecular layer was frequently observed. Some donor granule cells, implanted in the superficial aspect of the host molecular layer, migrated down along processes of Bergmann glia, which resembled the migration pattern of the normal development. Other granule cells attached to neuroglial processes which ensheathed capillary walls. While the migration of granule cells was found to be glial-dependent, the glial role in the migration of Purkinje cells was not clear. Purkinje cells probably migrated into the host molecular layer under favorable conditions where the loss of host Purkinje cells had been occurred to some extent and consequently followed by the increase of free axon endings of parallel fibers and interneurons of the host.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1977

Decay of genetic variability in geographically structured populations.

The ultimate rate and pattern of approach to equilibrium of a diploid, monoecious population subdivided into a finite number of equal, large, panmictic colonies are calculated. The analysis is restricted to a single locus in the absence of selection, and every mutant is assumed to be new to the population. It is supposed that either the time-independent backward migration pattern is symmetric in the sense that the probability that an individual at position x migrated from y equals the probability that one at y migrated from x, or it depends only on displacements and not on initial and final positions. Generations are discrete and nonoverlapping. Asymptotically, the rate of convergence is approximately (I-u)2t[I-(2NT)-1]t, where u, NT, and t denote the mutation rate, total population size, and time in generations, respectively; the transient part of the probability that two homologous genes are the same allele is approximately independent of their spatial separation. Thus, in this respect the population behaves as if it were panmictic.

Genetic Variation↗
PubMedDate not supplied

A spatial analysis of 100 surnames in England and Wales.

Spatial patterns are described and analysed for the 84 most common surnames in England and Wales, as well as 16 others selected for various reasons. At least three-quarters of the surname frequencies show spatial structure and are heterogeneous over the area of study. While they do not exhibit clines extending over the entire area of study, they do divide into four characteristics patterns. Spatial autocorrelation, while significant, is relatively low; similarity in surname frequency does not extend much beyond 100 km. Correlograms could be clustered to yield groups of surfaces denoting partial clines, isolation by distance, and differentiation at far distances. A method for detecting zones of rapid change found 21 such zones, mostly near the periphery of the study area. These boundaries do not indicate barriers to gene flow, but appear to be patterns brought about by historical factors. There are diffusion patterns between areas that differ greatly in surname composition, such as Wales and central England. There is little evidence of long-distance movements involving several surnames. At least three characteristic migration patterns, east-west and north-south diffusion and local dispersal, were found.

England↗
PubMedDate not supplied

Effects of migration on cancer incidence and resources for prevention and treatment in Florida.

Migration adds a complex dimension to the task of those who plan and allocate resources for health care. The authors offer a methodology for estimating the contribution of migration to the incidence of cancer, allow for age- and sex-specific cancer risks, and estimate, by country, the impact of recent migration on the annual incidence of cancer in Florida. Cancer and migration data were used to develop estimates of the number of cancer cases for Florida counties that were attributable to recent migrants. A net gain and loss ratio was calculated for new cancer cases in 1980 resulting from the 1975-80 migration pattern. Florida data was used because that State has one of the highest crude cancer incidence rates in the nation, is one of the most populous States, and has a population growth from migration rather than from natural increase. Preliminary findings on the relationship between cancer health services resources and net cancer rates from migration are discussed. County cancer health services resources had a strong positive relationship to population size, but the impact of migration on cancer incidence was in a curvilinear relationship to population size.

Cancer Care Facilities↗
PubMed1992

Phosphorylation by cAMP-dependent protein kinase inhibits the degradation of tau by calpain.

The effects of cAMP-dependent protein kinase (cAMP-PK) phosphorylation on the degradation of the microtubule-associated protein tau by calpain were studied. Purified bovine brain tau that had been phosphorylated by cAMP-PK had a slower migration pattern on sodium dodecyl sulfate-polyacrylamide gels and a more acidic, less heterogeneous pattern on two-dimensional, nonequilibrium pH gradient electrophoresis (NEPHGE) gels compared with untreated tau. Phosphorylation of tau by cAMP-PK significantly inhibited its proteolysis by calpain compared with untreated tau. To our knowledge this is the first demonstration that phosphorylation of tau by a specific kinase results in increased resistance to hydrolysis by calpain. Tau dephosphorylated by alkaline phosphatase migrated more rapidly on sodium dodecyl sulfate-polyacrylamide gels and also showed an altered two-dimensional NEPHGE pattern. Dephosphorylation of tau had no effect on its susceptibility to calpain proteolysis, indicating that regulation of the susceptibility to calpain hydrolysis is due to the phosphorylation of a specific site(s). These results suggest a role for phosphorylation in regulating the degradation of tau. Abnormal phosphorylation could result in a protease-resistant tau population which may contribute to the formation of paired helical filaments in Alzheimer's disease.

Animals↗
PubMed1979

Immunochemical cross-reactions between type III group B Streptococcus and type 14 Streptococcus pneumoniae.

Serological cross-reactions between certain streptococci and some serotypes of Streptococcus pneumoniae have been reported. These studies detail the serological cross-reactivity observed between hot HCl-extracted group b streptococcus type III (GBS III) antigens and S. pneumoniae type 14 (Pn 14) polysaccharide. Similar electrophoretic migration patterns of GBS III and Pn 14 were observed when either type-specific BGS III antisera or pneumococcal omniserum was utilized to precipitate these antigens. Both the GBS III antigen and the Pn 14 polysaccharide migrated toward the cathode, whereas all other pneumococcal polysaccharides migrated toward the anode. No cross-reactions were observed between GBS III antisera and the 11 other types of pneumococcal polysaccharides. Lines of identity were observed between type-specific GBS III antisera and monospecific Pn 14 antiserum with either GBS III antigens or purified Pn 14 polysaccharide. The cross-reacting antigens of GBS III and Pn 14 appear to be identical by immunodiffusion and immunoelectrophoresis.

Antigens, Bacterial↗
PubMed1979

Gel electrophoresis of rotavirus RNA derived from six different animal species.

Rotavirus RNA prepared from calf, pig, mouse, deer, foal and dog-adapted human isolates was compared using polyacrylamide gel electrophoresis. Reproducible differences in the RNA migration patterns were found between all isolates. There were 11 clearly resolved segments in the pig, mouse and foal samples. The calf rotavirus RNA and deer rotavirus RNA separated into 9 bands and 10 bands, respectively. The dog-adapted human virus migrated in 12 bands, and this probably results from the complex passage history of the original human rotavirus isolate.

Animals↗
PubMed1990

Characterization of monoclonal antihuman small bowel and colon specific mucin antibodies.

Three human small bowel and colon mucosal specific monoclonal antibodies with distinct morphologic and electrophoretic characteristics were generated by fusion of immunized Balb/c spleen cells and murine plasmacytoma cells. Morphologic specificity by indirect immunofluorescence (IIF) revealed three antibody binding patterns corresponding to villus surface (TP-NG-43), goblet cell apical granules (TP-NG-2), and a combined surface/goblet cell apical granule antibody (TP-NG-20). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) produced three distinct electrophoretic migration patterns. These antibodies reacted with very high molecular weight determinants: TP-NG-2, one band greater than 400 kD; TP-NG-20, two bands corresponding to 370-400 kD; and TP-NG-43, two bands in the 350-400-kD range with smaller bands in the 50-94-kD range. Cross-reactivity with various other human organ systems was evaluated by indirect immunofluorescence and SDS-PAGE electrophoresis with Western blotting. By IIF, all three monoclonal antibodies reacted very strongly with components of gastric mucosa. Weak cross-reactivity was seen with colon, rectum and mucin-producing adenocarcinoma of the colon. No cross-reactivity was observed by IIF with other mucin-containing and non-mucin-containing tissues. However, cross-reactivity with gastric mucin was not detected by enzyme-linked immunosorbent assay (ELISA) and Western blotting. Antibody reactivity with mucin was confirmed by purifying various regional gastrointestinal mucins and by subsequent testing by ELISA. Monoclonal antibody affinity columns were prepared and evaluated. The utility of these methods will allow for further definition of important goblet cell mucin glycoprotein characteristics and isolation of mucin subpopulations.

Antibodies, Monoclonal↗
PubMed1991

Patterns of immunoreactive pancreatic polypeptide in human plasma.

Pancreatic polypeptide (PP) is synthesized as an amino-terminal moiety of a precursor peptide and is released into plasma during stimulation as an amidated hormone (PP1-36). The purpose of this investigation was to ascertain the immunoreactive forms of PP in human plasma using HPLC chromatographic technique. Plasma was obtained from five normal volunteers under various postprandial intervals and from the Blood Bank. PP in each plasma sample was processed for HPLC analysis by immunoprecipitation and/or immunoaffinity extractions. Migration patterns of PP-forms were identified under isocratic elution. This study shows that human plasma contains four distinct immunoreactive (IR) forms of PP during stimulation by a protein-rich meal. These forms are PP1-36 (peak 4), PP3-36 (peak 3) and unidentified material migrating as peak 2 and peak 1. The corresponding migration constants were Kav 0.828 +/- 0.04, Kav 0.790 +/- 0.003, Kav 0.570 +/- 0.009 and Kav 0.409 +/- 0.007, respectively. The predominant fasting from of IR PP chromatographed as peak 1, while peaks 2 and 4 were reduced in amplitude. The 1 h and 3 h postprandial chromatograms of HPLC profiles of plasma PP were similar in shape but lower in relative magnitude and amplitude. The authenticity of peak 4 as the migration of native PP1-36 was confirmed using purified IR native PP1-36 extracted from human pancreas. Partial amino acid sequence analysis of PP peak 3 revealed deletions of two N-terminal amino acid residues. The chemical identities of peaks 1 and 2 are unknown but appear to differ from PP in peaks 3 and 4 by virtue of their migration profiles. It is concluded that there are at least four distinct IR forms of PP in human plasma. Native PP1-36 accounts for less than 1% of total PP after an overnight fast and is about 1/3 of total postprandial IR plasma PP. Discernment of the nature and etiology of forms of PP in plasma may provide a new understanding of the role of PP in mammalian physiology.

Adult↗
PubMed1992

DNA relatedness, karyotyping and gene probing of Candida tropicalis, Candida albicans and its synonyms Candida stellatoidea and Candida claussenii.

Isolates of Candida albicans with varied phenotypes, including sucrose-negative variants (C. stellatoidea, serotypes A and B) and avirulent germ tube-negative forms (C. claussenii) showed significant (greater than 90%) DNA relatedness to classical C. albicans, but insignificant relatedness to C. tropicalis and sucrose-negative C. tropicalis. A transverse alternating-field gel electrophoresis procedure (TAFE) showed discrete karyotype patterns among the phenotypic variants of C. albicans including the sucrose-negative C. stellatoidea. The number of chromosome-sized DNA bands for C. tropicalis (7 bands) were within the range of bands observed for C. albicans (5 to 10 bands). The general DNA-migration pattern for C. albicans appeared distinct from that of C. tropicalis. An aspartyl proteinase (PrA) gene probe from C. albicans hybridized with chromosomal DNA from C. albicans, C. claussenii and C. stellatoidea but not with that from C. tropicalis.

Aspartic Acid Endopeptidases↗
PubMed1977

Skin penetration of infective hookworm larvae. III. Comparative studies on the path of migration of the hookworms Ancylostoma braziliense, Ancylostoma ceylanicum, and Ancylostoma caninum.

The lateral skin areas of nine hookworm-free puppies were exposed to infective larvae of Ancylostoma braziliense, Ancylostoma ceylanicum and Ancylostoma caninum. Serial sections, stained with Harris' haematoxylin and eosin, showed that many similarities exist in the migration patterns of the hookworm species used. However, striking differences were observed between Ancylostoma braziliense on the one hand and Ancylostoma ceylanicum and Ancylostoma caninum on the other hand with regard to the speed with which the penetration occurred. Larvae of Ancylostoma braziliense may travel directly from the epidermis into the dermis--apart from migration via hair follicle systems--a path of migration we did not observe in infections with the other species used. Larvae of Ancylostoma braziliense seem to pass the skin more rapidly than those of Ancylostoma ceylanicum and Ancylostoma caninum. Many larvae of Ancylostoma ceylanicum managed to penetrate the skin 2--6 h after the onset of the exposure.

Ancylostoma↗
PubMed1992

Transcultural nursing and health care issues in urban and rural contexts.

The distinction between urban and rural health care has been based largely on population density, with little attention given to contextual meaning of patterns related to the lifeways of the people. When considering sociocultural factors, the differentiation becomes more complex. In this paper some of the transcultural nursing issues and challenges are discussed in relation to cultural context and health care trends in urban and rural settings. Four urban-rural health-related issues with transcultural dimensions are examined. Migration patterns, diversity among rural communities, utilization of services, and change related to intervention strategies are identified as transcultural nursing knowledge and practice in relation to urban and rural contexts.

Health Services Needs and Demand↗
PubMed1992

A bifunctional genetic regulatory element of the rat dopamine beta-hydroxylase gene influences cell type specificity and second messenger-mediated transcription.

Dopamine beta-hydroxylase, the enzyme which converts dopamine to norepinephrine, is expressed in a cell type-restricted pattern in neuroendocrine tissue. A segment of the rat gene containing 395 bases of 5'-flanking sequence regulates expression of a reporter gene in a cell type-selective pattern in mammalian cell cultures. Using deletion mutants of the 5'-flanking sequence, we have identified a 30-base genetic regulatory element, designated DB1, which enhances transcription from a heterologous promoter 5-20-fold in neuroendocrine cell lines. DB1-specific DNA-protein complexes are found in nuclear extracts from all cell lines examined, but the migration pattern differs between cell lines. The 5'-flanking region of the dopamine beta-hydroxylase gene is also responsive to cyclic AMP and phorbol ester treatment of SHSY-5Y neuroblastoma cells. The simultaneous presence of both effectors results in synergistic increases in DBH1 mRNA and reporter gene activity. The second messenger regulatory element was localized to the region containing the DB1 element, and reporter plasmids containing multiple copies of the DB1 element are responsive to treatment with inducers. The results of this study identify a cis-acting regulatory element which influences both cell type selectivity and second messenger responsiveness of the rat dopamine beta-hydroxylase gene.

Animals↗