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F Gilbert

Publications and source records attributed to F Gilbert.

144 records · Page 8Linked to original sources
PubMed1970

Regulation of acetylcholinesterase in neuroblastoma cells.

The specific activity of mouse neuroblastoma acetylcholinesterase (EC 3.1.1.7) increased 25-fold when the rate of cell division was restricted. The results show that acetylcholinesterase activity is regulated in neuroblastoma cells and that the regulatory mechanism is inversely related to the rate of cell division. Under the same conditions the specific activity of catechol-O-methyl transferase (EC 2.1.1.6) did not change significantly.

Acetylcholinesterase↗
PubMedDate not supplied

Maternal cell contamination of amniotic fluid cell cultures from two consecutive pregnancies complicated by fibroids.

The detection of maternal cells in amniocyte cultures is thought to be due to the outgrowth of cells from small fragments of maternal tissue removed by the amniocentesis needle. An unusual case is reported in which maternal cell contamination (MCC) was found in the cell cultures from a woman in two different amniocenteses from two consecutive pregnancies. Both pregnancies were complicated by the presence of fibroids and the fibroid tissue may have been the source of the maternal cells. A history of an amniocentesis in which there was MCC of cell cultures, or the detection of fibroids, may pose an additional risk for MCC attributable misdiagnosis in prenatal genetic studies.

Adult↗
PubMedDate not supplied

Amplified DNA with limited homology to myc cellular oncogene is shared by human neuroblastoma cell lines and a neuroblastoma tumour.

Amplified cellular genes in mammalian cells frequently manifest themselves as double minute chromosomes (DMs) and homogeneously staining regions of chromosomes (HSRs). With few exceptions both karyotypic abnormalities appear to be confined to tumour cells. All vertebrates possess a set of cellular genes homologous to the transforming genes of RNA tumour viruses, and there is circumstantial evidence that these cellular oncogenes are involved in tumorigenesis. We have recently shown that DMs and HSRs in cells of the mouse adrenocortical tumour Y1 and an HSR in the human colon carcinoma COLO320 contain amplified copies of the cellular oncogenes c-Ki-ras and c-myc, respectively. Both DMs and HSRs are found with remarkable frequency in cells of human neuroblastomas. We show here that a DNA domain detectable by partial homology to the myc oncogene is amplified up to 140-fold in cell lines derived from different human neuroblastomas and in a neuroblastoma tumour, but not in other tumour cells showing cytological evidence for gene amplification. By in situ hybridization we found that HSRs are the chromosomal sites of the amplified DNA. The frequency with which this amplification appears in cells from neuroblastomas and its apparent specificity raise the possibility that one or more of the genes contained within the amplified domain contribute to tumorigenesis.

Cell Line↗
PubMedDate not supplied

Age at first pregnancy in relation to age at menarche and year of birth in Caucasian, Japanese, Chinese and part-Hawaiian women living in Hawaii.

A multiple regression analysis was undertaken to examine the relationship between age at first pregnancy and recollected age at menarche and sociological variables in Caucasian, Japanese, Chinese and part-Hawaiian parous women living in Hawaii. The analysis was conducted using the medical history records of 1198 Caucasian, 1770 Japanese, 453 Chinese and 578 part-Hawaiian women. Age at first pregnancy varied significantly among ethnic groups. Initial results showed an apparent heterogeneity among ethnic groups in the effect of age at menarche on age at first pregnancy. Once appropriate controls for the linear and non-linear effects of year of birth were made, the effects of age at menarche on age at first pregnancy no longer varied significantly among ethnic groups. The observed secular trends in age at first pregnancy have varied widely among the four ethnic groups studied and appear unrelated to genetic background.

Adult↗
PubMedDate not supplied

Ethnic intermarriage and its consequences for cystic fibrosis carrier screening.

Cystic fibrosis gene mutations can vary in frequency between different ethnic populations. However, there is a rising trend of ethnic intermarriage in the United States, a situation suggesting that differences in specific mutation frequencies currently apparent in Europe may not persist for long in this country. Therefore, limited mutation screens targeted at specific ethnic groups and risk calculations based on data from more homogeneous European populations may not be appropriate in the United States. The genetic consequences of ethnic admixture are also likely to extend to other recessive diseases (e.g., Tay-Sachs, thalassemia), which, in the past, have been limited largely to particular ethnic, racial, or religious subgroups, with implications for public health agencies overseeing newborn screening programs for genetic diseases and for clinical genetics programs offering population-based carrier-detection programs, carrier risk assessment, and counseling.

Cystic Fibrosis↗