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Biomedical subjects

M P Farrell

Publications and source records attributed to M P Farrell.

29 records · Page 2Linked to original sources
PubMed1986

A recombinant murine retrovirus for simian virus 40 large T cDNA transforms mouse fibroblasts to anchorage-independent growth.

A recombinant murine retrovirus containing the intact cDNA sequence for the simian virus 40 (SV40) large T antigen (T) was constructed by using the pZIPNeo SV(X)1 vector. Psi 2 packaging cells were then transfected, and G418-resistant clones were used to generate helper-free viral stocks. NIH 3T3 mouse fibroblasts infected by the recombinant T cDNA retrovirus were selected fro G418 resistance. Such cultures synthesized authentic SV40 T and were transformed to anchorage-independent growth at high efficiency. Therefore, this vector has allowed the study of the transformation properties of T under conditions of neutral drug selection and in the absence of SV40 small t antigen.

Animals↗
PubMed1980

Polypeptide synthesis and phosphorylation in Epstein-Barr virus-infected cells.

Epstein-Barr virus superinfection of the human lymphoblastoid cell line Raji, a Burkitt lymphoma-derived line that contains Epstein-Barr virus genomes in an episomal form, results in the sequential synthesis of 29 detectable proteins, which range in molecular weight from approximately 155,000 to 21,000, and in the shutoff of the bulk of host protein synthesis within 6 to 9 h after infection. There are three classes of virus-induced proteins; these are an early class, consisting of eight proteins synthesized by 6 h postinfection, an intermediate class, containing two proteins synthesized 9 h postinfection, and a late class, consisting of five proteins synthesized 12 h postinfection. In addition, there is a fourth class of polypeptides, called persistent, that are found both before and after superinfection. The rates of synthesis of the proteins fall into three patterns; these are pattern A, in which the rate of synthesis decreases, pattern B, in which the rate of synthesis remains steady, and pattern C, in which the rate of synthesis increases after the initial appearance of the polypeptide. Both 9-(2-hydroxy-ethoxymethyl)guanine (acyclovir) and phosphonoacetic acid inhibit the appearance of one intermediate protein and at least three late proteins. Seven polypeptides are phosphorylated at different times after infection.

Acyclovir↗
PubMed1978

T antigen of BK papovavirus in infected and transformed cells.

BK virus T antigen from BKV-transformed rat and hamster cells and from productively infected monkey cells has been examined by immunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Forms of the antigen that migrate as proteins of 86,000 and 92,000 daltons have been identified. Both forms can be labeled by 32P.

Animals↗
PubMed1976

Identity and crisis in middle aged men.

The authors selectively review disparate literature bearing on the issue of the male mid-life transition. There is considerable evidence that the entrance into middle age is associated with stress and often maladaptive patterns of reaction. There is little available information, however, on the specific nature of the stressors, their differential impact, or the factors associated with the individual's attempted style of adaptation to them. Through the process of exploring relevant findings from sociology, social and clinical psychology, and popular fiction we attempt to specify a working model of the experience of entering middle age. The authors see this model as being of heuristic value in that it specifies a number of dimensions to be operationalized which may, together, provide a more holistic view of the changes in the self-system undergone by the middle aged male.

Adult↗
PubMed1976

Effects of Sevin on the reproductive biology of the Coturnix.

Adult Coturnix quail (Coturnix coturnix japonica) were subjected to three levels of carbaryl pesticide treatment (Sevin-20 p.p.m., 40 p.p.m., and 400 p.p.m) and monitored to observe any modifications in either their reproductive biology or behavior. There was an increase in the amount of pesticide excreted with increasing treatment levels during the first 48 hours following intubation, after which pesticide levels in the fecal material for all groups approached zero. Addditionally, significant amounts of the pesticide were detected in the egg yolks after pesticide ingestion (treatment levels, 20, 40, and 400 p.p.m. resulted in pesticide residues of 1.58, 2.03, and 3.15 p.p.m., respectively). Egg production was significantly reduced (p less than or equal to 0.05), although egg viability was not affected by the pesticide stress. Agonistic behavior decreased in males while it increased in the females following pesticide ingestion.

Aggression↗
PubMed1975

Rapid determination of the amount of cetylpyridinium chloride bound by bacteria.

A modification of the Colowick and Womack procedure for measuring ligand binding by macromolecules is described for drug binding by bacteria. This technique is based on the determination of drug concentration in the dialysate from a bacteria-drug mixture at equilibrium. The dialysis cell of the original procedure was replaced by a Minibeaker (Bio-Rad), which has a larger membrane surface area, and the dialysate was continuously monitored with a spectrophotometer equipped with a flow cell. With this system, only 3 min was required to determine the amount of cetylpyridinium chloride bound by Escherichia coli K-12 strain P678. Possible applications of the technique are discussed.

Absorption↗
PubMedDate not supplied

Statistical analysis of structure-activity relationships.

The relationship between organic structure and biological activity (toxicity) is examined by statistically comparing concentration-response regression lines among structurally related compounds. Response data from acute toxicity tests are initially transformed to the logistic function while concentration data are transformed to the logarithm base 10 before being fit to a linear model using a weighted least squares analysis. A sequential approach is presented that uses statistical models for testing differences among related compounds. The approach first tests for the overall equality of regression lines (slopes and intercepts). If the regression lines are found to be different, another set of tests are conducted to determine if the slopes of the lines are equal (i.e. parallel). If the slopes are equal, multiple comparisons are made using Scheffé's procedure for determining which compounds differ in their intercepts. Relative toxicities are then estimated for various concentrations of particular compounds.

Regression Analysis↗
PubMedDate not supplied

Reasons for non-attendance at a child guidance clinic.

A consecutive group of children (n = 19) referred to a child guidance clinic who failed to attend an initial interview were followed-up. These 'non-attenders' did not differ from a matched group of 'attenders' with respect to duration or nature of their problems, waiting period for the appointment, type of referring agencies or socio-demographic variables, but were more likely to be living with their natural parents. Disinclination among the parents was the main reason for absenteeism and could be related to ignorance about the clinic. The problems leading to referral persisted in most cases and had not received further treatment.

Child↗