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At least 253 records · Page 14Linked to original sources

[Distribution of the ABO blood groups and the HP, TF, GC, PI and C3 serum proteins in Yakuts].

In Yakut populations examined, polymorphisms of immunological and serum protein markers, including AB0 and Rhesus blood groups, HP, TF, GC, PI and C3, were revealed. Gene frequencies for the systems studied fell into the following ranges: AB0 system: r, 0.514 to 0.663; p, 0.136 to 0.306; q, 0.110 to 0.337; haptoglobin HP*1: 0.214 to 0.431; transferrin TF*C: 0.700 to 1.0; group specific component GC*1: 0.821 to 0.978; PI*M1 proteinase inhibitor (or alpha 1-antitrypsin) PIM1: 0.860 to 0.946; and third component of the complement C3*F: 0.031 to 0.143.

ABO Blood-Group System↗

[The use of discrete characters in discriminant analysis for diagnosis of pulmonary tuberculosis and for classification of patients differing in treatment efficiency based on polymorphisms at nine codominant loci-HP, GC, TF, PI, PGM1, GLO1, C3, ACP1 and ESD].

Discriminant analysis was used to differentiate patients with pulmonary tuberculosis (N = 106) from healthy individuals (N = 328) and patients whose treatment was efficient (N = 71) from those whose treatment was inefficient (N = 35). The analysis involved the data on nine polymorphic codominant loci: HP, GC, TF, PI, PGM1, GLO1, C3, ACP1, and ESD. The loci were selected by significance of differences in genotype frequencies between tuberculosis patients and healthy controls (GC, TF, PI, C3, ACP1) or between the two groups of patients differing in treatment efficiency (HP, GC, PI, PGM1, C3, ESD). Discrimination was based on a graphic method of Bayes classification procedure with a single-variate nomograph allowing easy estimation of the a posteriori probabilities for an individual to be classified. The two groups of patients proved to be discriminated sufficiently well (probability of misclassification Perr = 0.24), whereas discrimination between tuberculosis patients and healthy individuals was less efficient (Perr = 0.33). The method was proposed as a means of predicting the efficiency of treatment in pulmonary tuberculosis. Along with clinical, roentgenological, and laboratory examination, discriminant analysis may be employed as an accessory test in diagnostics of pulmonary tuberculosis, especially when the diagnosis is questionable.

Adult↗

[Genetic structure of the Mongols as derived from the ABO, MN, Rh, EsD, GLO1, PGM1, AcP, 6-PGD, Hp, Gc, Tf, C'3 and ChE2 loci].

According to integral characterization of gene frequencies of the investigated loci AB0, MN, Rh, GLO1, PGM1, EsD, AcP, 6-PGD, Hp, Tf, Gc, C'3 and ChE2, Mongolian population has high level of polymorphism, with the exception of haplotypes R" (cdE) and Ry(CdE) at the Rh locus and TfB0-1 at the Tf locus. The data on biochemical and immunological polymorphic gene markers analysed in the population of Mongolia show that the Mongolians have some distinctive features, in comparison with the mean-in-the-world characteristics: high frequencies of the B genes at the AB0 locus; D, E, R1 and R2 at the Rh locus; GLO11, PGDc, TfDChi, E2(C5+), PGM1(1+); low frequencies of the genes A(AB0), R0(Rh), AcPc, Hp1, Gc2, C'3F, PGM 1(2-); the rest of the genes at the above-mentioned loci and the genes of the locus MN have the mean-in-the-world frequencies.

ABO Blood-Group System↗

[Distribution of C subtypes and other Tf variants in populations of the USSR].

Serum samples from seventeen Caucasoids and Mongoloid populations of the USSR were tested for transferrin (Tf) subtypes. According to Tf patterns, the Caucasoids groups had high TfC1 frequency, whereas Mongoloids are characterized by increased frequency of TfC2 suballele. The following gene frequencies were observed: TfC1 - 0.8515, TfC2 - 0.1166, TfC3 - 0.0129, TfD - 0.0129, TfB - 0.0065 for Russians of Yegoryevsk town; TfC1 - 0.8663, TfC2 - 0.0930, TfC3 - 0.0233 for West-Pamirian populations of Khuf, those being for Pastkhuf 0.8476, 0.1159 and 0.0244, respectively. Mongoloid populations demonstrate following frequencies of five genes described (in the order shown above): 0.7870, 0.1620, 0.0232, 0.0139 for Kirghizes of East Pamir; 0.7963, 0.1805, 0.0050, 0.0182 for Buriats of Suduntui; 0.7647, 0.1985, 0.0074, 0.0221, 0.0037 and 0.0037 (gene TfDX) for Buriats of Sakhiurta, the frequencies of these genes being 0.7647, 0.1985, 0.0074, 0.021, 0.0037 and 0.0037 for Aginsky national district, Chita Region. The total sample of Buriats of Gakhan cluster (Ust-Ordyn national district) and Olkhon island of Irkutsk Region demonstrates following frequencies of genes (in the same order): 0.7876, 0.1962, 0.0012, 0.0057, 0.0082 and 0.7679 and 0.2321, respectively. In addition, a rare anodal variant designated tentatively TfC12Like was found among Pamir populations. The results obtained are compared with those reported for world populations.

Alleles↗

[Localization of the genes coding for the specific modification-restriction system in the E. coli tF strain].

The recombinant Escherichia coli tF strain has been shown to have its own specific modificational and restrictional system. In order to establish the location of genes, coding this system a plasmid has been isolated from the investigated strain, which substantiates the resistance to streptomycin. The plasmid DNA has been transformed into a recipient strain, E. coli O, which has no modificational and restrictional system of its own. The newly obtained E. coli O (ptF) transformants also have proved negative with regard to their testing for the presence of a specific modificational and restrictional system. The conclusion follows that the genes, coding the modificational and restrictional system of the E. coli tF strain are not located in the plasmid isolated from it.

Chromosomes, Bacterial↗

Distribution of group specific component (GC) and transferrin (TF) subtypes in populations of Sri Lanka.

A random sample of 503 individuals from five endogamous groups of Sri Lanka was studied for the genetic polymorphism of the group specific component (GC) and transferrin (TF) using isoelectric focusing. Both systems showed statistically significant heterogeneity among the five main populations of the island. The GC allele frequencies of Malays are significantly different from those of the other four populations (Sinhalese, Tamils, Moors and Burghers). However, the TF system shows less variation, since only the Moors show a significant heterogeneity compared to Tamils and Burghers. The frequencies found in the present study are very different from those reported for the populations of the Indian mainland.

Alleles↗

The lack of susceptibility to HIV-1 infection in human hematopoietic progenitor TF-1 cell line correlates with the absence of LFA-1 (CD11a) surface adhesion molecule.

Although substantially unsusceptible to HIV-1 infection, human hematopoietic progenitors (CD34+ cells) express significant amounts of gp120-binding CD4 molecules. As some experimental evidence suggests the need for one or more putative cellular accessory factor(s) for efficient CD4-mediate HIV-1 infection, we analyzed the presence and distribution of various adhesion molecules on the surface of two HIV-1-susceptible cell lines (H9 and A3.01) and one HIV-1-unsusceptible, CD4-positive, human hematopoietic progenitor cell line (TF-1). The only difference observed concerned the LFA-1 CD11a protein that has already been shown to be necessary for cell fusion in HIV-1-infected T4 lymphocytes. CD11a was present in a high percentage of HIV-1-susceptible cells and absent in HIV-1-unsusceptible TF-1 cells. A significant increase in HIV-1 replication was obtained in CD11a-enriched H9 cells in comparison with an almost completely CD11a-deprived H9 cell population. The lack of susceptibility to HIV-1 infection in human CD34+ cells may depend on various factors. Nevertheless, the lack of CD11a in a CD34+, CD4+ human hematopoietic progenitor cell line suggests that this molecule may be implicated in the susceptibility to HIV-1 infection.

Antigens, CD↗

CD4 engagement by HIV-1 in TF-1 hematopoietic progenitor cells increases protein kinase C activity and reduces intracellular Ca2+ levels.

Starting from our previous observations that the HIV-1-mediated engagement of CD4 induced apoptotic death of TF-1 hematopoietic progenitor cells, in this study we evaluated PKC activity and intracellular Ca2+ levels in TF-1 cells treated with viable and heat-inactivated HIV-1 (strain IIIB) or anti-CD4 Leu3a monoclonal antibody (mAb). Both viable and heat-inactivated HIV-1 or anti-CD4 mAb, but not anti-human cytomegalovirus (HCMV) 66kD protein or anti-CD8 mAb induced a rapid (5-10 min) increase in PKC activity under both serum-containing and serum-free conditions. The same treatment also induced both a transient and a long-lasting (48 hours) decrease (p < 0.05) in intracellular Ca2+ levels in serum-containing cultures. We propose that the observed changes in PKC activity and intracellular Ca2+ levels might be involved in the HIV-1 mediated apoptosis of hematopoietic progenitor cells.

Antibodies, Monoclonal↗

The first exon of Ad12 E1A excluding the transactivation domain mediates differential binding of COUP-TF and NF-kappa B to the MHC class I enhancer in transformed cells.

The major histocompatibility complex class I enhancer is the target for adenovirus-12 E1A-mediated down-regulation of class I transcription. In Ad12 transformed rodent cells, the class I enhancer is down-regulated through increased binding of the repressor COUP-TF to the R2 element and decreased binding of the activator NF-kappa B (p50/p65) to the R1 element. The reduced surface levels of class I antigens contribute to the tumorigenic potential of Ad12 transformed cells by favoring their immunoescape from cytotoxic T-lymphocytes. Previous studies using transformed cells containing hybrid Ad5/Ad12 E1A (plus Ad12 E1B) genes have indicated that sequences within the first exon of the 266R Ad12 E1A gene are required for class I down-regulation and tumorigenesis. In this study we demonstrate that these same sequences, which exclude the Ad12 CR3 transactivation domain, are also required for increased COUP-TF binding to the R2 element and decreased NF-kappa B binding to the R1 element of the class I enhancer. We further show that diminished NF-kappa B binding is not due to a lack of NF-kappa B1-p50 in the nuclei of Ad12 transformed rat cells.

Adenovirus E1A Proteins↗

Acetylsalicylic acid and sodium salicylate inhibit LPS-induced NF-kappa B/c-Rel nuclear translocation, and synthesis of tissue factor (TF) and tumor necrosis factor alfa (TNF-alpha) in human monocytes.

We have investigated the effects of acetylsalicylic acid and sodium salicylate on the LPS-induced synthesis of the pro-coagulant protein tissue factor (TF) and the pro-inflammatory protein tumor necrosis factor-alpha (TNF-alpha), as well as the prostaglandin PGE2 in human monocytes. Both drugs dose-dependently inhibited LPS-induced TF and TNF-alpha synthesis at the mRNA and the protein level, and reduced PGE2 production. As evidenced by electro mobility shift assay (EMSA) and the use of a NF-kappa B prototypic probe, these drugs probably exert their inhibitory effects by interference with the nuclear translocation of NF-kappa B/c-Rel proteins. These data may expand the understanding of the anti-thrombotic and anti-inflammatory effects of these drugs when activation of monocytes occurs.

Anti-Inflammatory Agents, Non-Steroidal↗

Divergent cortical connections to entorhinal cortex from area TF in the macaque.

The entorhinal cortex (EC) is an important component of the medial temporal lobe memory system in the primate and is often viewed as a "gatekeeper" area that passes on highly convergent cortical inputs toward the hippocampus. Further analysis of these connections at a microcircuitry level regarding the actual size and shape of arbors and terminations is not yet available, but may contribute to understanding the role of the EC in memory or other functions. The main emphasis of this report was on serial section analysis of anterogradely labeled axons that project from area TF (lateral parahippocampal cortex; Bonin and Bailey, 1947) to the EC (n = 12). By way of evaluating network organization, other projections from area TF--to TH (in the medial parahippocampal gyrus; n = 5) and to posterior visual areas (n = 3)--were also investigated. All three systems were found to terminate heavily in layer 1, as expected from previous investigations, but some terminations were verified in layer 6 of the EC as well. This technique further demonstrated that terminal fields are widely divergent and elongated. In the EC, terminal fields extended over 6-11 mm and spanned multiple cell islands and interislands. These axons resemble "feedback" cortical connections by virtue of their layer 1 terminations and their markedly divergent geometry, but not by their origin from layer 3. Spatially extended terminal fields recall the nontopographic, distributed character of olfactory connections and raise questions of how these features might be related to the memory functions attributed to medial temporal regions.

Animals↗

Classification of transferrin (Tf) subtypes by isoelectric focusing.

A sample of 450 sera from unrelated individuals from Southern Germany was examined by isoelectric focusing on polyacrylamide gels. Three common subtypes, TfC1, C2-1, and C2, were differentiated. In addition, the rare variants TfB1, B1-2, B2, D1, D1-2, D2, and D3 were observed. The frequencies of the Tf alleles in our sample were found to be: TfC1 = 0.8544, TfC2 = 0.1367, TfB1 = 0.0011, TfB1-2 = 0.0022, TfB2 = 0.0045, and TfD1 = 0.0011. Analysis of 73 parents with 73 children did not show deviations from the expected mode of inheritance. Modification of the method by addition of 0.01 M FeCl3 to the sera prior to examination did, however, reveal further variation and permitted the distinction of six subtypes, C1, C2-1, C2, C3, C3-1, and C3-2.

Adult↗

Human transferrin (Tf) and group-specific component (Gc) subtypes in Tunisia.

Simultaneous subtyping of two genetic markers--group-specific component (Gc) and transferrin (Tf)--by electrofocusing enabled us to compute the following gene frequencies for the Tunisian population: Gc1S, 0.525; Gc1F, 0.260; Gc2, 0.215; TfC1, 0.770; TfC2, 0.215; TfD1, 0.015. The frequencies of TfD, TfC2, and Gc1 are higher than those found in Caucasoid populations and can be explained by Negroid contribution. A selective advantage related to the metabolic role of this vitamin D-binding protein does not seem very likely for any particular Gc type or subtype. It is postulated that the differences in the frequencies of the Gc alleles might be related to selective advantage for genes belonging to other genetic systems originally closely linked to either Gc1 or to Gc2 alleles.

Blood Proteins↗

Isoelectric focusing of rare transferrin (Tf) variants and common TfC subtypes.

TransferrinC (TfC) subtypes were determined by isoelectric focusing (PAGIF) on samples from 90 carriers of the TFB and TfD alleles. In all cases of CB and CD heterozygotes only one of the two common subtypes of the TfC allele, TfC1 or TfC2, was observed. This is considered strong support for the hypothesis of two common alleles at the Tf locus. The different isofocusing patterns of rare B and D variants are compared with the results obtained after agarose gel electrophoresis (AGE).

Alleles↗

IL-13 and IL-4 share signal transduction elements as well as receptor components in TF-1 cells.

IL-13 and IL-4 are growth factors for the human erythroleukemia cell line TF-1. In these cells both cytokines share overlapping binding sites, but the number of sites for IL-13 is half of that for IL-4. Two monoclonal antibodies against the extracellular domain of the IL-4R alpha chain completely abolish the binding of IL-13, although IL-13 does not bind to this chain. Following receptor triggering, IL-13 and IL-4 induce the phosphorylation of a 170 kDa protein, probably the IL-4-induced phosphotyrosine substrate. In addition the phosphorylation of the 170 kDa protein results in its tight association with phosphatidylinositol-3-kinase.

Antibodies, Monoclonal↗

Transferrin (Tf) polymorphism: an analysis by isoelectric focusing.

The polymorphism of the transferrin (Tf) system was studied in a total of 300 unrelated Japanese individuals from Miyagi prefecture, the northern part of Japan using isoelectric focusing in thin-layer polyacrylamide gel. In our population samples three common phenotypes and nine variants were observed. The calculated allele frequencies were TfC1 = 0.773, TfC2 = 0.212, TfDchi (Chinese) = 0.008, and the combined frequencies for the TfBvar (variants) = 0.007. Family data (n = 44) were in accordance with an autosomal codominant fashion of inheritance. The use of isoelectric focusing procedure among Japanese will raise the probability of excluding a man falsely accused of paternity to 15.8% as compared with 1.5% when the conventional electrophoretic methods are used.

Asian People↗