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A Sajantila

Publications and source records attributed to A Sajantila.

17 recordsLinked to original sources
PubMed1995

Characterization and radiosensitivity of UT-EC-2A and UT-EC-2B, two new highly radiosensitive endometrial cancer cell lines derived from a primary and metastatic tumor of the same patient.

UT-EC-2A was established from a patient with moderately differentiated Stage III endometrial adenocarcinoma with squamous metaplasia. UT-EC-2B was established from the same patient 17 months later from a metastasis in the left supraclavicular fossa. The origin of these cell lines was confirmed by DNA identity testing. Nude mice tumors produced by UT-EC-2A and UT-EC-2B cells recapitulated the histology of the original human tumors. Flow cytometric DNA contents of both primary and metastatic human tumors as well as corresponding nude mice tumors were diploid. The S-phase fractions of both cell lines were > or = 30%. The UT-EC-2A cell line was cytogenetically normal. The UT-EC-2B cell line had quite simple karyotype at low passage with an extra i(18p) and a deletion 21q, but at higher passages an additional three-way translocation 5;14;19 was observed. Radiosensitivity of the cell lines was tested with the 96-well plate clonogenic assay. The areas under the survival curves corresponding to the mean inactivation doses of UT-EC-2A and UT-EC-2B were 0.65 +/- 0.10 and 0.60 +/- 0.06 Gy, respectively. Measured survival at 2.0 Gy (SF2) was 0.042 for UT-EC-2A, 0.044 for UT-EC-2B, and 0.2 for skin fibroblasts. These cell lines are among the most radiosensitive human cancer cell lines described in the literature. Studying the characteristics of primary and metastatic cells derived from the same patient provides an opportunity to evaluate tumor progression.

Adenocarcinoma↗
PubMed1994

A microsatellite polymorphism in the von Willebrand factor gene: comparison of allele frequencies in different population samples and evaluation for forensic medicine.

The allele frequencies at the tetranucleotide repeat (TCTA) vWA locus in the vWF gene were determined in the general Finnish population, in a population representing an internal isolate of Finland, in the Vologda-Russian population, and in US Black population samples. The allele and genotype frequencies from these population samples were compared with each other and with those reported from Spanish and British population samples. Statistically significant differences were demonstrated between most of the different groups (Finns vs. Vologda-Russians, Finns vs. US Blacks, Finns vs. Spanish, Vologda-Russians vs. US Blacks, Vologda-Russians vs. Spanish, US Blacks vs. Spanish and US Blacks vs. British Caucasians), but not between the two Caucasoid population samples from Finland and Great Britain, nor between or within the subpopulation samples from Finland and those from Vologda-Russia. In addition, the vWA marker was evaluated and demonstrated to be reliable for forensic purposes and paternity testing.

Adult↗
PubMed1994

Mitochondrial DNA sequences from Switzerland reveal striking homogeneity of European populations.

Mitochondrial DNA sequences from 74 Swiss individuals were compared to sequences from British and Finish populations. We found that the nucleotide sequence differences between these populations are almost as low as those within the populations. This is in contrast to three African populations, which display substantial differences between each other. The homogeneity of the mitochondrial gene pool in Europe suggests a recent common ancestry for European populations. This may reflect the arrival of anatomically modern humans about 40,000-30,000 years ago or, alternatively, the spread of agriculturalists about 10,000-6,000 years ago. Taking into account the estimated rate of evolution of the mitochondrial control region, the data favor the former explanation.

Black People↗
PubMed1993

Forensic DNA typing by the solid-phase minisequencing method.

We describe a method for DNA-typing, in which a panel of biallelic markers are detected by the solid-phase minisequencing method (Syvänen et al., 1990). This method identifies single nucleotide variations in DNA fragments amplified by the PCR. Determination of the panel of 12 markers selected in this study proved to be an efficient and reliable method for forensic identification of individuals. We also introduce a novel approach for rapid determination of allele frequencies by quantitative analysis of pooled DNA samples.

Alleles↗
PubMed1993

Determination of allele frequencies at loci with length polymorphism by quantitative analysis of DNA amplified from pooled samples.

We present a new method that allows rapid determination of allele frequencies at loci exhibiting length polymorphism. In this method a fluorescence-labeled PCR primer is used to amplify the polymorphic region from pooled DNA samples originating from a large number of individuals. The fluorescent PCR products are separated by gel electrophoresis on an automatic DNA sequencer and the relative amount of the PCR products are determined. The distribution of the PCR products obtained from the alleles present in the pooled samples directly corresponds to the allele frequency in the population in question. The allele frequencies at a short tandem repeat locus in the von Willebrand factor gene and at the D1S80 locus were determined in the Finnish population. We found that the allele frequencies determined by quantitative analysis of PCR products from pooled DNA samples and by analyzing individual samples were in good agreement.

Alleles↗
PubMed1993

Identification of individuals by analysis of biallelic DNA markers, using PCR and solid-phase minisequencing.

We have developed a new method for forensic identification of individuals, in which a panel of biallelic DNA markers are amplified by the PCR, and the variable nucleotides are detected in the amplified DNA fragments by the solid-phase minisequencing method. A panel of 12 common polymorphic nucleotides located on different chromosomes with reported allele frequencies close to .5 were chosen for the test. The allele frequencies for most of the markers were found to be similar in the Finnish and other Caucasian populations. We also introduce a novel approach for rapid determination of the population frequencies of biallelic markers. By this approach we were able to determine the allele frequencies of the markers in the Finnish population, by quantitative analysis of three pooled DNA samples representing 3,000 individuals. The power of discrimination and exclusion of the solid-phase minisequencing typing test with 12 markers was similar to that of three VNTR markers that are routinely used in forensic analyses at our institute. The solid-phase minisequencing method was successfully applied to type paternity and forensic case samples. We also show that the quantitative nature of our method allows typing of mixed samples.

Adult↗
PubMed1992

Genetic susceptibility to multiple sclerosis linked to myelin basic protein gene.

Genetic factors have been implicated in the aetiology of multiple sclerosis (MS), but the genes conferring susceptibility to MS have not been identified. We carried out genetic linkage and association analyses by studying polymorphism of the myelin basic protein (MBP) gene on chromosome 18, a candidate gene for MS, in 21 MS families, 51 additional unrelated patients with definite MS, and 85 controls. All subjects were Finnish, and 14 of the families were from an area with an exceptional familial clustering of MS. Magnetic resonance imaging (MRI) was used to examine subclinical disease in symptom-free family members. In the association analysis, the allele frequencies between MS patients and controls differed significantly, p = 0.000049), the difference being attributable mainly to a higher frequency of a 1.27 kb allele among patients. In the linkage analysis, based on an autosomal dominant model and penetrance 0.05, a maximum LOD score of 3.42 (theta = 0.00) was obtained when patients with optic neuritis and their symptom-free siblings with abnormal MRI findings were classified as "affected". When these subjects were classified as "unknown" the maximum LOD scores ranged from 2.99 to 3.25 (theta = 0.00). The results suggest that in this population genetic predisposition to MS is closely linked to the MBP gene and that polymorphism at the MBP locus or an adjacent locus has a role in the aetiology of MS.

Adult↗
PubMed1992

Isolation of two keratinocyte cell lines derived from HPV-positive dysplastic vaginal lesions.

Explant cultures were started from human papillomavirus (HPV)-infected genital lesions in order to isolate and propagate abnormally differentiating cells from squamous intraepithelial neoplasia. A medium with high calcium concentration was used to induce terminal differentiation of cells from surrounding normal epithelium. Two cell lines with extended life-spans were established. The UT-DEC-1 cell line was derived from an HPV-33-positive mild vaginal dysplasia (VAIN I). In cultured UT-DEC-1 cells, HPV 33 DNA was detected with Southern-blot hybridization and the polymerase chain reaction (PCR) technique. The restriction pattern of HPV 33 changed during early passages and flow cytometric analysis detected a decrease in chromosomal DNA content. HPV 33 RNA from the E6-E7 region could be amplified by PCR at late passage. UT-DEC-2 cell line was derived from an HPV-16-positive moderate vaginal dysplasia (VAIN II). HPV 16 DNA was also detected in cultured cells by the PCR technique. The senescence of normal keratinocytes and growth selection in favor of aneuploid cells was observed by flow cytometric analysis at subsequent passages. Karyotype analysis showed clonal chromosomal abnormalities in both cell lines. To date, UT-DEC-1 cells have undergone 40 and UT-DEC-2 cells 25 passages. This study shows that the isolation of HPV-infected dysplastic cells can be achieved by culturing the cells in a medium with high calcium concentration. The cell lines presented provide the opportunity of evaluating the early stages of squamous-cell carcinogenesis.

Adult↗
PubMed1992

Amplification of three hypervariable DNA regions by polymerase chain reaction for paternity determinations: comparison with conventional methods and DNA fingerprinting.

The present study evaluates the usefulness of a PCR-based method for routine paternity testing in 35 paternity cases. This identification method which is based on amplification of three hypervariable genetic loci, apoB, D1S80 and HLA-DQ alpha, is compared, with regard to reliability and technical feasibility, to the conventional identification methods based on protein polymorphisms and to Southern blot hybridizations with multi- and single locus probes. Data obtained by PCR-amplification of these three loci resulted in paternity indices (56.1, geometric mean value) which are at the same level as the corresponding values derived from standard genetic blood group markers (42.7). The geometric mean value of the paternity indices obtained by Southern blot hybridization using three single locus probes (190.6) was more informative, and the most informative analysis proved to be Southern blot hybridization with multilocus probes. The technical feasibility and the reproducibility of the PCR-based analysis is, however, overwhelming, and if several highly polymorphic loci are amplified, the resolving power of PCR-analysis is similar to that obtained using multilocus probes.

Blood Grouping and Crossmatching↗
PubMed1992

DNA profiling in a genetically isolated population using three hypervariable DNA markers.

We determined the allele frequencies for three hypervariable DNA loci D2S44, D1S7 and D7S21 using the probes YNH24, MS1 and MS31 in the genetically isolated Finnish population. The allelic length ranges were 1.7- < 6.0 kb for YNH24, 1.7- < 18.0 kb for MS1 and 3.2- < 12.0 kb for MS31. High heterozygosity rates (0.94-0.96) were detected for all three probes. In 48 mother-child pairs no mutations were found using the probes YNH24 and MS31, whereas a mutation rate of 0.064 was observed for probe MS1. In addition, an unexpected four-band pattern was detected in 1 out of 170 individuals using the probe MS1, suggesting complex DNA polymorphism based on both a variable number of tandem repeats and restriction site polymorphism. Our findings also show that all three probes are valuable in individual identification in this genetically isolated population.

Adult↗
PubMed1992

Amplification of reproducible allele markers for amplified fragment length polymorphism analysis.

A procedure for amplification by PCR of reproducible allele markers for amplified fragment length polymorphism (Amp-FLP) analysis is presented. We have prepared markers for the allelic products of the VNTR loci D1S80 (MCT118) and D17S30 (YNZ22) and for the hypervariable VNTR locus close to the 3' end of the apolipoprotein B gene (apoB) by re-amplifying a mixture of PCR products from individuals with known alleles. These allele markers allow precise and discrete determination of the VNTR alleles at these loci using the Amp-FLP technique that should prove suitable in forensic analyses, paternity testing and population studies.

Alleles↗
PubMed1992

PCR amplification of alleles at the DIS80 locus: comparison of a Finnish and a North American Caucasian population sample, and forensic casework evaluation.

Allele and genotype frequencies for the highly polymorphic D1S80 locus were determined in a Finnish population sample by using PCR followed by high-resolution PAGE and silver staining, a procedure called the amplified-fragment-length polymorphism (Amp-FLP) technique. In 140 unrelated Finnish individuals 15 alleles and 43 phenotypes were observed. The D1S80 locus demonstrated a heterozygosity of .77, and the power of discrimination was .92 in this sample representing a genetically isolated Finnish population. The distribution of observed genotypes conformed to Hardy-Weinberg expectations. In 36 mother-child pairs Mendelian inheritance for the alleles at the D1S80 locus could be demonstrated in all cases, and no mutations were observed. The usefulness of the D1S80 locus for forensic casework was assessed by using Amp-FLP analysis of the D1S80 locus in 36 forensic cases including 18 rapes, 14 homicides, and 4 other violent crimes. In most cases valuable information was obtained using the Amp-FLP technique, and in no case was there indication of either false-positive or false-negative results.

Alleles↗
PubMed1991

The distribution of the HLA-DQ alpha alleles and genotypes in the Finnish population as determined by the use of DNA amplification and allele specific oligonucleotides.

Allele and genotype frequencies for the HLA-DQ alpha locus were determined for use in forensic analyses and paternity tests in Finland. The polymerase chain reaction (PCR) and the reverse dot blot format were employed to detect 6 different HLA-DQ alpha alleles. All 6 HLA-DQ alpha alleles were detected among the 112 unrelated individuals with allele frequencies ranging from 5.8% to 32.6%. The distribution of the observed genotypes is in Hardy-Weinberg equilibrium. Additionally, this Finnish population sample is statistically similar to 2 other Caucasian sample populations. The power of discrimination of this system in the Finnish population sample is 0.92, suggesting this method may prove suitable for identification purposes.

Alleles↗
PubMed1991

The polymerase chain reaction and post-mortem forensic identity testing: application of amplified D1S80 and HLA-DQ alpha loci to the identification of fire victims.

The application of DNA typing methods after amplification by the polymerase chain reaction (PCR) of DNA derived from body tissues from charred fire victims was investigated. A total of 26 different tissue specimens from ten extensively burned individuals were analyzed. The samples included femoral muscle, psoas muscle, bone marrow and blood. The post-mortem period varied from 38 to 183 h. After amplifying the DNA by PCR from the various tissues, the D1S80 locus was analyzed with a high resolution polyacrylamide gel electrophoresis technique followed by silver staining and the alleles of the HLA-DQ alpha locus were detected by using a reverse dot blot format. All samples could be typed for both loci and the genotypes were consistent in the various tissues from each individual. A parentage test was performed in two cases and Mendelian inheritance of the alleles for both loci was observed.

Alleles↗
PubMed1991

Identification of individuals with DNA testing.

The fast technical development in molecular biology and the increasing knowledge of the human genome has had a major impact on forensic medicine. Genetic characterization of individuals at the DNA level enables identity testing from a minimal amount of biological specimen in cases of sexual assault, homicide, and unknown human remains. Also paternity testing is changing from level of gene products to the genomic level. This article addresses some of the advantages of DNA testing over the conventional forensic serology, and the DNA techniques currently used in forensic science.

ABO Blood-Group System↗
PubMed1990

Amplification of the hypervariable region close to the apolipoprotein B gene: application to forensic problems.

Our purpose was to identify individuals from blood stains in two murder cases. We used primers flanking the hypervariable region of the apoB gene to amplify DNA extracted from blood stains and blood samples from suspected persons. The sensitivity and specificity of the procedure was improved by carrying out two consecutive PCR amplifications with a nested set of primers in the second amplification. The size of the generated fragments was determined by polyacrylamide gel electrophoresis followed by staining with ethidium bromide. By comparing the fragments produced from the stains with those from the blood samples we were able to identify the origin of the blood stains in both cases.

Apolipoproteins B↗