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T Papp

Publications and source records attributed to T Papp.

50 records · Page 3Linked to original sources
PubMed1989

Differentiation between papillary and nonpapillary renal cell carcinomas by DNA analysis.

Recent studies have shown that the deletion of chromosome 3p or the loss of DNA sequences at 3p is generally associated with the development of renal cell carcinoma (RCC). However, chromosome analysis of some papillary RCCs suggested that this type of tumor differs genotypically from the most common nonpapillary RCCs. Therefore, by using cytogenetic and molecular genetic approaches, we examined human papillary and nonpapillary RCCs for the loss of heterozygosity or homozygosity at the short arm of chromosome 3. The constitutional heterozygosity for the DNF15S2 locus and for one allele of the c-erbA beta and the c-raf-1 proto-oncogenes was lost in nonpapillary RCCs, whereas both alleles were retained in each papillary RCC analyzed. We conclude that the loss of DNA sequences at the chromosome 3p region is a genomic change occurring consistently in nonpapillary RCCs, but never occurring in papillary RCCs.

Carcinoma, Renal Cell↗
PubMed1988

Beta-globin gene linked DNA haplotypes and frameworks in three South-East Asian populations.

DNA haplotypes and frameworks (numbers in parenthesis) linked to the beta-globin gene were determined by restriction fragment analysis using eight restriction endonucleases on 86 (97) chromosomes bearing the normal beta-globin gene (HBB*A) and 108 (118) chromosomes bearing HBB*E in subjects homozygous for HBB*A or HBB*E from three South-East Asian populations with high HBB*E frequencies (northern Thailand, north-eastern Thailand and Cambodia). A systematic nomenclature for beta-globin gene-linked haplotype characterized by six polymorphic sites is introduced. In all populations, HBB*A occurred preferentially (greater than 80%) in linkage with the haplotype 41 (+----+) and all three frameworks described by Antonarakis et al. (1982). In contrast, almost 80% of the HBB*E genes occurred with the haplotype 27 (-+- ). In northern and north-eastern Thailand, HBB*E was present almost exclusively in frame-work 2; HBB*E in framework 3 (Asian) was limited to the Khmer population of Cambodia, and the frequency of HBB*E-linked framework 3 increased from the west to the east in this country.

Asia, Southeastern↗
PubMed1988

Nondisjunction reduplication of chromosome 3 is not a common mechanism in the development of human renal cell tumors.

Because of the recurrent loss of regions of the chromosome 3 short arm in renal cell carcinomas, a chromosomal mechanism for the expression of recessive cancer genes has been implicated in the development of this type of tumor. Nondisjunction and subsequent reduplication of a mutant chromosome is one of the presumed mitotic mechanisms leading to the expression of recessive cancer genes. Using variant fluorescence at the centromeric region of chromosome 3 and a restriction fragment length polymorphism on chromosome 3p, we found chromosome 3 heteromorphism in the constitutional cells of 14 of 15 patients with renal tumors showing two normal chromosomes 3. This heteromorphism was maintained in each tumor. Therefore, the mechanism of nondisjunction and reduplication in the development of homozygosity for a mutant chromosome 3 in renal tumors remains questionable.

Chromosomes, Human, Pair 3↗
PubMed1988

Alpha-thalassemia in northern Thailand. Frequency of deletional types characterized at the DNA level.

The frequency of alpha-thalassemias in northern Thailand was estimated using DNA techniques. Among 106 healthy adult Thais from the Chiangmai area, 28 were shown to carry alpha-globin gene anomalies. There were 19 heterozygotes and 1 homozygote for alpha-thalassemia-2. One of the alpha-thalassemia-2 deletions was of the -alpha 4.2 type and the remaining 20 of the -alpha 3.7 type (subtype I). Deletions of both alpha-globin genes on one chromosome (alpha-thalassemia-1) of the Southeast Asian type were observed in 5 cases, and 3 alpha-globin gene triplications were identified. Compared with a previous report on alpha-thalassemia in northern Thailand which was based on the determination of hemoglobin Bart's in cord blood, the present DNA study reveals a similar frequency of alpha-thalassemia-2 but a considerably lower frequency of alpha-thalassemia-1.

Chromosome Deletion↗
PubMed1988

DNA haplotypes and frameworks associated with the beta-globin gene in the Kachari population of Assam (India).

DNA haplotypes and frameworks associated with the beta-globin gene were determined in a Tibeto-Burman group, the Kachari, from Upper Assam, India, using restriction analysis at eight restriction sites. Of the total of 59 subjects, 26 were homozygous for HBB*A and 33 homozygous for HBB*E. Complete haplotype determination in 33 subjects revealed a conspicuous difference in haplotype distribution between HBB*A- and HBB*E-bearing chromosomes. The Southeast Asian HBB*E-associated haplotype -+- +- (27-2 in the present terminology) predominated on HBB*E chromosomes. The previously established beta-globin-associated frameworks 1, 2 and 3 were evenly distributed among the HBB*A chromosomes, whereas all HBB*E chromosomes had framework 2. These findings favor a common origin of the HBB*E gene in Southeast Asia and Assam.

Adult↗
PubMed1988

Frequency of deletional types of alpha-thalassemia in Kampuchea.

The frequency of deletional types of alpha-thalassemias in the Khmer population of Kampuchea (Cambodia) was estimated using DNA techniques. Among 58 healthy adult Kampucheans from rural areas, 17 had alpha-globin gene anomalies. There were 14 heterozygotes and two homozygotes for alpha(+)-thalassemia; the remaining test subject carried a deletion of both alpha-globin genes (alpha(0) -thalassemia of the Southeast Asian type) on one chromosome 16, and triple alpha-globin genes on the other. All of the 18 alpha(+)-thalassemia deletions were of the -alpha 3.7 type (17 subtype I, 1 subtype II). The restriction pattern obtained with the enzyme RsaI and comparison of the intensity of hybridization with alpha-globin and beta-globin gene probes yielded no evidence of total deletion of the alpha-gene complex. The prevalence of deletional alpha(+)-thalassemia in Kampuchea is higher, and that of alpha(0)-thalassemia is lower than in neighbouring Thailand.

Blotting, Southern↗
PubMed1977

Juvenile pernicious anemia associated with intestinal nodular lymphoid hyperplasia and immune deficiency state. Report of a case.

A 17-year-old girl with humoral immune deficiency state was observed, in whom pernicious anemia developed one year before her death. The patient died after a very severe diarrheal attack and respiratory tract infection. The necropsy revealed intestinal nodular lymphoid hyperplasia. The immunological evaluation showed depressed IgG and IgM concentration with lack of IgA, however in the patient's blood there were found B lymphocytes containing IgA immunoglobulin. On the effect of crude gastric antigen the patient's lymphocytes showed M.I.F. release, although there were no circulating autoantibodies.

Adolescent↗
PubMedDate not supplied

Mutational analysis of the PTEN/MMAC1 tumour suppressor gene in primary human malignant mesotheliomas.

Eighteen primary human malignant mesotheliomas obtained from 18 patients were screened for point mutations and microdeletions/insertions in all exons of the tumour suppressor gene PTEN/MMAC1 by SSCP analysis. No mutation could be found. Our preliminary data indicate that disarrangements of PTEN/MMAC1 are at least not frequently involved in mesothelioma formation.

Genes, Tumor Suppressor↗
PubMedDate not supplied

Introducing foreign genes into fish eggs with electroporated sperm as a carrier.

A new method has been developed for introduction of foreign genes into fish eggs. The procedure is based on the incubation of fish sperm cells suspended in dilute citrate solution with plasmid DNA, followed by application of high-field-strength electrical pulses (electroporation) to increase DNA binding., uptake, or both. Tissue homogenates and genomic DNA extracts of free swimming fry developed from eggs fertilized with treated sperm was tested to evaluate the efficiency of gene transfer. Dot blot hybridization and gene expression assay demonstrated the presence and expression of the reporter genes introduced in 2.6 to 4.2% of several hundreds of tested larvae of common carp (Cyprinus carpio L.), African catfish (Clarias gariepinus), and tilapia (Oreochromis niloticus). No transgene has been found in the fry resulting from parallel experiments without sperm electroporation. This is the first report on successful application of electroporated sperm cells for production of transgenic fish.

Animals↗