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N J Nowak

Publications and source records attributed to N J Nowak.

48 records · Page 3Linked to original sources
PubMed1993

A human chromosome 11 NotI end clone library.

A NotI end clone library has been constructed from a human-hamster hybrid cell line containing only human chromosome 11. Fifty-one NotI clones were chosen to characterize the library. The majority of NotI clones hybridize to small 15- to 200-kb fragments and have proven to be valuable for chromosome 11 physical mapping by detecting fragments not previously recognized by random probes. These NotI end clones have been used to isolate corresponding NotI linking cosmids which were then used to identify adjacent NotI fragments on pulsed-field gels. The clones were mapped using fluorescence in situ hybridization and a somatic cell hybrid panel. Although these clones were localized over the entirety of chromosome 11, a nonrandom distribution was observed. Northern blot analysis indicated that 57% (17/30) of the NotI clones examined detected poly(A)+ transcripts in HeLa cell RNA.

Animals↗
PubMed1993

A chromosome 11 YAC library.

A targeted yeast artificial chromosome (YAC) library for chromosome 11 has been constructed from the J1 cell line that carries a single human chromosome 11 within a hamster DNA background. Interspecies chimeric clones generated during construction of the library were detected during the screening process and eliminated from the library. Contig assembly becomes much less difficult using such a library as the complexity is decreased and the ends of the clone inserts can be rescued for walking to neighboring clones. The library contains > 1824 clones with an average insert length of 337 kb. This represents a fourfold coverage of chromosome 11 or a > 95% chance of recovering a unique single-copy sequence from the library. Two hundred YAC clones were localized by fluorescence in situ hybridization and found to be randomly distributed along the chromosome. The library has been screened with probes for the chromosome 11 markers HBB, GLUR4, H19, and D11S193. Corresponding YAC clones have been isolated for each locus. This analysis has indicated that the library is unbiased, that cognate YAC clones can be recovered with chromosome 11 markers, and that extensive contig assembly should be feasible.

Animals↗
PubMed1989

The human mineralocorticoid receptor gene (MLR) is located on chromosome 4 at q31.2.

The gene for the human mineralocorticoid receptor (MLR) was previously localized to chromosome 4. Here, we have localized this gene to 4q31.2 by in situ hybridization. This precise mapping of MLR will assist in the linkage analysis and genetic characterization of pseudohypoaldosteronism, an autosomal recessive disorder which likely results from a defect in the MLR gene.

Animals↗
PubMed1988

Two anonymous DNA segments distinguish the Wilms' tumor and aniridia loci.

The association of Wilms' tumor with aniridia (the WAGR complex) in children with 11p13 chromosomal abnormalities has been established, but the paucity of molecular probes in 11p13 has hampered identification of the responsible genes. Two new anonymous DNA segments have been identified that map to the WAGR region of 11p13. Both DNA probes identify a cytologically undetectable deletion associated with a balanced chromosome translocation inherited by a patient with familial aniridia, but not Wilms' tumor. The same two DNA segments are also included in the distal p13-p14.1 deletion of another patient, who has aniridia, Wilms' tumor, and hypogonadism, but they are not included in the p12-p13 deletion of a third patient, who does not have aniridia but has had a Wilms' tumor. The discovery of this aniridia deletion and these two DNA segments that physically separate the Wilms' tumor and aniridia loci should facilitate identification of the genes in the WAGR locus, beginning with the aniridia gene.

Animals↗
PubMed1988

Four new DNA markers are assigned to the WAGR region of 11p13: isolation and regional assignment of 112 chromosome 11 anonymous DNA segments.

One hundred eighty-three human single copy clones were isolated from the Livermore Laboratory chromosome 11 library (ID code LL11NSO1) and 112 of them were mapped to chromosome 11. Using a panel of somatic cell hybrids segregating chromosome 11 translocations and short arm deletions, 54 of the clones were assigned to one of nine segments on the short arm of chromosome 11; the remainder were assigned to the long arm. Nine of these clones map to 11p13, and four of the nine [57(D11S89), 530(D11S90), 706(D11S93), and 1104(D11S95)] are confined to the same segment within p13 that contains catalase (CAT), the beta subunit of follicle stimulating hormone (FSHB), and the Wilms' tumor-aniridia (WAGR) gene complex.

Catalase↗
PubMed1986

The chromosome 11 gene map: genes for growth and development, Wilms' tumor deletions, and cancer chromosome breakpoints.

Human chromosome 11 is clearly a model autosome encoding genes and characteristics associated with both normal and abnormal growth and development, and several significant disorders. A fine-structure molecular, genetic, and physical map of this chromosome would add considerably to our knowledge of the organization and control of human genes and to an understanding of normal and abnormal human biology.

Animals↗
PubMed1986

Characterization of a new primary human pancreatic tumor line.

A primary human pancreatic tumor line (BxPC-3) has been established from a biopsy specimen of a histologically confirmed adenocarcinoma of the body of the pancreas. Tumorigenicity was proven by xenograft in athymic nude mice. Upon re-establishment of tumor xenografts in tissue culture, the epithelial tumor cells retained their original morphology. Histopathologically, the tumors grown in nude mice exhibited the original characteristics of the primary adenocarcinoma in the patient, producing traceable mucin and displaying moderately well to poorly differentiated adenocarcinomas with occasional lymphocytic infiltrations at the tumor peripheries. Furthermore, the tumor xenografts differentially expressed carcinoembryonic antigen, human pancreas cancer-associated antigen, and human pancreas-specific antigen. Karyotyping and glucose-6-phosphate dehydrogenase isoenzyme characterization revealed that this tumor line was of human origin and devoid of HeLa cell contamination. The BxPC-3 tumor line has been maintained for more than four years in our laboratory and represents a valuable model for primary human pancreatic cancer.

Adenocarcinoma↗
PubMed1983

Correlation of tumor-cell growth in four semisolid systems.

The correlation of the colony growth of cells disaggregated from human melanoma, sarcoma, lung, and ovarian carcinomas were studied in four different semisolid tissue culture assays: (a) the soft agar assay of Pluznik and Sachs; (b) the soft agar assay of Hamburger and Salmon; (c) the soft agar-methyl cellulose assay of Buick et al.; and (d) the methyl cellulose assay of Ogawa et al. There was no colony growth of tumor cells achieved in 15 of 15 cases assayed in Ogawa's methyl cellulose assay. The plating efficiency of the above mentioned tumors was similar in the assays of Pluznik and Sachs, Hamburger and Salmon, and Buick et al. However, the tumor take rate differed among these three systems. The assay of Buick et al. appears potentially useful for analysis of the biology of human tumors.

Adenocarcinoma↗
PubMed1981

The soft agar clonogenicity and characterization of cells obtained from human solid tumors by mechanical and enzymatic means.

A two-step procedure for releasing cells from solid tumors has been applied to specimens of human melanoma, sarcoma, lung, colon, and breast carcinoma. The first population released mechanically has been compared with the population subsequently released enzymatically in tests of dye exclusion, ribonucleoside triphosphate pool sizes, intactness of DNA, and clonogenicity in soft agar. While greater numbers of dye-excluding cells are released in the enzymatic step, and these cells have higher ribonucleoside triphosphate pools and more intact DNA, both populations contain clonogenic cells in approximately equal numbers. Several semisolid media were employed in tests of clonogenicity, and all methods employing an agar underlayer appeared satisfactory and approximately equivalent in cloning efficiency. The methyl cellulose upper layer system facilitated implanting of pooled colonies into nude mice, which resulted in growth in the nude host and marked increase in cloning efficiency when the cells were replanted into soft agar-methyl cellulose plates. A comparison of four different areas of individual tumor specimens was made with cells released enzymatically and measuring cell yield, dye exclusion, ATP pool size, and uptake and metabolism of 5-fluoropyrimidines. Only relatively small variations were seen from one area to the next, with trypan blue exclusion exhibiting the least variation, and metabolism of fluorinated pyrimidines showing the most.

Animals↗