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Dive into the research topics where Walter A. Nelson-Rees is active.

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Featured researches published by Walter A. Nelson-Rees.


Cancer | 1974

CHARACTERIZATION OF A NEWLY DERIVED HUMAN SARCOMA CELL LINE (HT-1080)

Suraiya Rasheed; Walter A. Nelson-Rees; Eva Toth; Paul Arnstein; M. Gardner

A tumor cell line was derived from the fibrosarcoma of a 35‐year‐old Caucasian man who died without having received chemotherapy or radiotherapy. The in vitro growth properties and transplantability into antithymocytic sera treated mice were characteristic of these malignant cells. An aberrant karyology with marker chromosomes was present. No virus particles were detected.


Somatic Cell and Molecular Genetics | 1981

Specific chromosome loss associated with the expression of tumorigenicity in human cell hybrids

Eric J. Stanbridge; Robert R. Flandermeyer; David W. Daniels; Walter A. Nelson-Rees

Four related nontumorigenic and tumorigenic HeLa × fibroblast intraspecific human hybrid cell lines were analyzed to determine whether specific chromosome(s) are associated with the control of tumorigenic expression. The loss of one copy each of both chromosome 11 and chromosome 14 were associated, with a high degree of statistical significance, with the expression of tumorigenicity in two segregants derived from the original nontumorigenic hybrid population. Although the parental origin of the chromosomes could not be established in this study, our preliminary results suggest that complex, genetically determined, regulatory interactions may operate in the control of neoplastic expression.


Science | 1974

Banded Marker Chromosomes as Indicators of Intraspecies Cellular Contamination

Walter A. Nelson-Rees; Robert R. Flandermeyer; Paula K. Hawthorne

Chromosome banding revealed marked chromosomes characteristic of HeLa cells in cultures designated HEK, HEK/HRV, HBT-3, HBT-39B, MA160, and a strain of SA-4TxS-Husa1. Ohter HeLa cell characteristics found were glucose-6-phosphate dehydrogense type A mobility and lack the Y chromosome. Conventional chromosome analysis and immunological and enzymatic technique serve to monitor species specificity and racial origin of the donor. Chromosome banding, however, can monitor intralinear karyotype peculiarity and its evolution during long-term cultivation.


Chromosoma | 1980

Heterochromatinization, chromatin elimination and haploidization in the parahaploid mite Metaseiulus occidentalis (Nesbitt) (Acarina: Phytoseiidae)

Walter A. Nelson-Rees; Marjorie A. Hoy; Richard T. Roush

Embryogenic mitoses, mitoses in females and spermatogenesis are described in the predatory mite Metaseiulus occidentalis (Nesbitt). At 22° C, egg development lasts approximately 4 days. Six chromosomes are seen in mitotic metaphases and anaphases of 0–24 h eggs. Toward the end of this period some embryo squashes have patches of cells containing nuclei which are partially heteropycnotic. These patches of cells apparently increase in size with the age of the embryo. In approximately 1/2 of all 24–48 h-old eggs they encompass all or most cells of the embryo. In these embryos metaphases involved 6 chromosomes, anaphases 3. Either prior to, or following metaphase, a pairing of chromosomes appeared to take place to form 3 units which resembled meiotic diplotene chromosomes where there is opening out between homologues. At metaphase, two sets of 3 chromosomes were slightly differentially stained. One, designated the H set, was darker and slightly more contracted than the other, the E set. At anaphase, 3H and 3E chromosomes segregated in a reductional division retaining the differential contraction until telophase. No cytokinesis appeared. The H set appeared to remain contracted while the E set decontracted to assume the appearance of an interphase nucleus. Both of these entities, side-by-side, created the partially heteropycnotic nucleus mentioned above. The H set then appeared to be excluded from the cell. Mitotic meta and anaphases involving 6 chromosomes were noted in female deutonymphs. Spermatogenesis appeared to encompass an equational division of 3 chromosomes, with the formation of a binucleate spermatid. Two tail structures appeared juxtaposed at the edge of each spermatid and thereafter a separation into two individual sperms occurred. —While mitosis was not studied in known males, we believe that the embryos exhibiting heterochromatinization and elimination of chromosomes in most or all cells were in fact demonstrating parahaploidization.


In Vitro Cellular & Developmental Biology – Plant | 1976

Source, alterations, characteristics and use of a new dog cell line (Cf2Th)

Walter A. Nelson-Rees; R. B. Owens; P. Arnstein; A. J. Kniazeff

SummaryA cell line derived from normal fetal canine thymus (Cf2Th) has been in culture since 1967. During cultivation the cells have changed morphologically from a fibroblast-like to flat, fusiform appearance and karyologically from diploid (2n=78) with 76 telocentric autosomes to hypodiploid with newly formed atelocentric chromosomes. The cells retain canine characteristic enzyme activity (G6PD and LDH) as well as cell membrane fluorescence and are free of mycoplasma. High passage cells produce tumors in ATST mice. No endogenous viruses have been detected in these cells. No original publication exists, to date, on the origin of this line, but seed stocks thereof have been distributed to many laboratories and the cells have served as experimental substrates in a number of published works in oncology albeit under different designations. The present information is offered in order to establish the provenance of this valuable cell line and to list characteristics which may serve to monitor for its purity and to distinguish it from other existing cell lines of dog origin also in common use.


Cytogenetic and Genome Research | 1967

Debut and Accumulation of Centric Fusion Products: An Index to Age of Certain Cell Lines

Walter A. Nelson-Rees; Alexis J. Kniazeff; Norman B. Darby

Fourteen cell lines derived from cattle ( Bos taurus ), sheep ( Ovis arks ), goat ( Capra hircus ) and dog ( Canis familiaris ) were


In Vitro Cellular & Developmental Biology – Plant | 1977

Establishment and characterization of a cell line derived from a spontaneous murinelung carcinoma (M109)

Richard M. Schultz; Phillip Ruiz; Michael A. Chirigos; Ursula I. Heine; Walter A. Nelson-Rees

SummaryThe Madison lung (M109) tumor cell line, initiated from a “spontaneous”, anaplastic murine lung carcinoma, has been propagated continuously in vitro for more than 300 cell generations. Cytogenetic analysis revealed a mouse karyotype with a mode of 78 chromosomes (2n=40). Three distinct marker chromosomes were identified by trypsin-giemsa banding. The cells piled up in culture and had a short generation time and high plating efficiency. Electron microscopy revealed highly undifferentiated cells with little rough endoplasmic reticulum, an abundance of free polysomes, the presence of few and often oddshaped mitochondria, lipid bodies and phagocytic vacuoles. Virus particles of the C-type were found frequently. The subcutaneous transplantation of M109 cultured cells at a relatively low cell inoculum produced highly metastatic tumors in syngeneic BALB/c mice.


Cytogenetic and Genome Research | 1966

Chromatin Bridges and Origin of Multinucleate Cells in a Bovine Testicular Cell Line

Walter A. Nelson-Rees; Alexis J. Kniazeff; Norman B. Darby

In the course of cytological observations of a cell line of bovine testicular origin since its initiation, many chromatin bridges and binucleate cells were noticed following the apparently spontaneous occurrence of chromatid fragmentation and formation of dicentric chromosomes. Subsequently, the frequency of binucleate cells and their respective nuclear sizes were recorded from permanent slides of material of passages made prior to, during, and after the incidence of chromatid fragmentation. Since the frequency of binucleate cells rose simultaneously with that of the chromatin bridges, and since the same nuclear size was involved in most cases, the frequency of chromatin bridges was taken as an index of their contribution to the production of binucleate cells following the period of chromatid fragmentation.


Virology | 1978

Endogenous type C RNA virus of mink (Mustela vison).

Vaclav Klement; Mary F. Dougherty; Pradip Roy-Burman; Bijay K. Pal; S.Susan Shimizu; Robert W. Rongey; Walter A. Nelson-Rees; Robert J. Huebner

Abstract A type C RNA virus was isolated from mink lung cell line (American Type Culture Collection No. CCL 64) which had been cocultivated with 5-bromodeoxyuridine (BUDR)-treated mouse spleen cells. The virus has type C RNA virus morphology as demonstrated by electron microscopy. The complement fixation and immunofluorescent tests performed with mouse anti-p30 antisera show a distinctive difference between mink and mouse type C viruses. Complement fixation tests also indicate that mink type C virus is antigenically different from rat, feline leukemia, feline endogenous (RD-114), baboon, and woolly monkey type C viruses. The virus propagates in cells of mouse, rat, cat, sheep, dog, and human origin, but not in bovine (MDBK) or simian (BSC-1) cells. The infection of rabbit (SIRC) cells and cells of virus origin (mink lung) was followed by delayed and low-titer polymerase release in tissue culture media. The virus sediments in sucrose density gradients as a broad band of densities, 1.13–1.17 g/ml, and contains 70 and 4S RNA. The protein profile is similar to that observed in other mammalian type C viruses. The DNA complementary to the poly(A)-containing virion RNA hybridized to a high degree (72%) with the RNA from virus-producing mink lung cells but not with the RNA from mouse cell lines or uninfected mink lung cell line. The nucleotide sequences homologous to mink viral cDNA were found in mink cell DNA from both virus-producing and nonproducing cells, but not in the DNA of mouse, rat, or feline origin. The virus here described therefore represents an endogenous mink type C virus.


Chromosoma | 1970

Chromosomes of the murine leukemia virus indicator cell line XC.

Walter A. Nelson-Rees

A cell line derived from the Rous Sarcoma Virus induced rat tumor XC (Svoboda), which was recently utilized as an indicator for the presence of murine leukemia virus growing in mouse cells, has been examined karyologically. The cells differ considerably from each other as well as from the normal rat karyotype (Rattus norvegicus, 2n=42). The modal chromosome number is 41. All cells bear one or more chromosome markers in common as well as non-rat-like chromosomes, but rat-like chromosomes still preserve the identity of species origin.

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Johng S. Rhim

National Institutes of Health

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M. Gardner

University of California

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Paul Arnstein

University of California

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Robert J. Huebner

United States Public Health Service

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Helene S. Smith

California Pacific Medical Center

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