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Biomedical subjects

B J White

Publications and source records attributed to B J White.

At least 73 records · Page 4Linked to original sources
PubMed1972

Studies of mice with a balanced complement of 36 chromosomes derived from F 1 hybrids of T1Wh and T1Ald translocation homozygotes.

F(1) hybrids with 38 chromosomes, including single T1Wh and T1Ald translocations, resulted when mice homozygous for the Robertsonian translocations T1Wh and T1Ald were crossed. Meiotic studies of the hybrids showed two trivalents, indicating nonhomology of the T1Wh and T1Ald chromosomes. The hybrids had frequent (25%) unbalanced meiotic metaphase II complements; one trisomic mouse resulted from six F(1) crosses. The F(1) crosses also produced one mouse with 36 chromosomes homozygous for both T1Wh and T1Ald, as well as mice with balanced polymorphic complements of 37, 38, 39, and 40 chromosomes. By crossing the F(2), a homogeneous line with 36 chromosomes was established. The line is phenotypically normal, fertile, and has balanced meiotic metaphase II complements. Analysis of the chromosomes of these mice with quinacrine mustard and the Giemsa-banding technique confirmed that T1Wh and T1Ald consisted of chromosomes 5;19 and 6;15, respectively. Crosses between this line and other existing translocation stocks may produce new strains of mice with even further reduction in chromosome number. Accumulation of Robertsonian translocations, a possible evolutionary mechanism in the wild, can be studied in the laboratory. F(1) hybrids from certain crosses are also an important model for human translocation carriers; both have similar meiotic abnormalities and often have aneuploid offspring.

Aneuploidy↗
PubMed1967

In vitro transformation by the adenovirus-SV40 hybrid viruses. II. Characteristics of the transformation of hamster cells by the adeno 2-, adeno 3-, and adeno 12-SV40 viruses.

Primary weanling hamster kidney cultures were transformed with the adeno 2-SV40, adeno 3-SV40, and adeno 12-SV40 hybrid viruses and with adenovirus type 12. The transformed cell lines which were established were characterized with respect to morphology, virus and antigen content, and chromosome aberrations. The adeno 2 and adeno 3-SV40 hybrid transformed cells had the morphology and T antigen content characteristic of SV40 transformations; cells transformed by the former hybrid had cytogenetic changes typical of SV40-transformed cells as well. The adeno 12-SV40 transformed cells were similar morphologically to adeno 12-transformed cells, contained both the SV40 and adeno T antigens and demonstrated the karyotypic instability of SV40-transformed cells, indicating that both viral genomes are operative in these cells. Although the results indicate that the SV40 genome in hybrids derived from the moderately or nononcogenic adenoviruses supplies the determinants for most of the characteristics investigated, and perhaps for oncogenesis, evidence was presented which suggests that a portion of a nononcogenic adenovirus genome may be integrated in adeno 2-SV40 transformed cells and directs the synthesis of adenovirus T antigens.

Adenoviridae↗
PubMedDate not supplied

Cytogenetic studies of males with schizophrenia. Screening for the fragile X chromosome and other chromosomal abnormalities.

Genetic factors appear to play a role in the etiology of schizophrenia, although no specific genetic mechanism has yet been identified. As a preliminary measure in the search for the chromosomal location of a gene or genes relevant to this illness, cytogenetic screening of populations of patients might provide clues for further in depth molecular studies. Additionally, since the X chromosome has been implicated as a possible site, specific examinations aimed at identifying abnormalities in this chromosome including the presence of the fragile X site, could also be important. The following report reviews the previous literature on chromosomal aberrations in schizophrenia and presents data from a new survey of 46 unrelated male patients with schizophrenia. No chromosomal aberrations or folate-sensitive fragile sites were found in samples from these patients.

Adult↗
PubMedDate not supplied

Focal dermal hypoplasia: ocular manifestations in a male.

Focal dermal hypoplasia (Goltz Syndrome) is a rare congenital disorder resulting from ectodermal and mesodermal dysplasia. It involves ocular tissues in over 40% of cases. Considered to be X-linked dominant, the disorder characteristically occurs in females. This case represents, however, the ninth male affected by this disease to be reported in the literature. Ocular abnormalities included colobomatous microphthalmia, aniridia, and recurrent papillomas arising from the conjunctiva and lid margins. Both light and electron microscopic studies performed on papillomatous tissue failed to demonstrate the presence of viral particles. Prometaphase chromosome analysis performed on peripheral blood cells, and on papilloma cells grown in tissue culture, showed a normal male karyotype of 46, XY.

Abnormalities, Multiple↗