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Domes are multicellular structures generated from confluent monolayers of mammary epithelium under the influence of insulin and a corticosteroid hormone. The hemicyst structure and occurrence patterns of domes suggest an in vitro analogy to organized acini of mammary parenchyma. Two activities of dome cells, vegetative replication of the mammary tumor virus and synthesis of casein, suggest a functional analogy between domes and acini. The corticosteroid hormone is considered the primary hormonal stimulant for dome formation. Evidence is presented that RNA and protein synthesis is required for the corticosteroid effect, as are intact active transport functions of epithelial cells.

This study investigated school innovativeness and a number of variables commonly found to be associated with this phenomenon in similar North American studies. Analysis of data collected from a sample of Victorian Catholic secondary schools revealed that only teacher age and extent of professional reading appeared to be significantly related to innovativeness. Subsequent factor analysis suggested the importance to school innovativeness of a ‘career consolidation’ factor and an ‘awareness’ factor. The concept of organizational inertia, developed as part of the theoretical framework of this study, also emerged as a relatively important concept.

THE search for RNA-containing human breast cancer viruses has been helped by the discovery of several biochemical and biophysical characteristics of the oncornavirus group1–4. Although these properties may not be unique to oncornaviruses5, they provide biological reagents for more discriminating tests6–8 to establish species of origin, natural history and virus taxonomy for candidate viruses exhibiting these properties.

Mammary tumor virus (MTV) replication was confined primarily to cells organized as acini in intact mouse mammary glands. Primary mammary tumors maintained a high degree of acinar organization and cells therein continued to replicate MTV vegetatively. Nonacinar mammary cells, derived by serial transplantation of acinar tumor cells, no longer actively replicated MTV. This suggests that phenotypic differences exist among mammary epithelial cells in their ability to support virus replication, that a fundamental relationship exists between the organization of epithelium for secretion and active virus replication, and that this relationship is not altered as a primary consequence of neoplastic transformation. Mammary epithelial cells from pregnant, non-tumor-bearing, MTV-infected BALB/cfC3H mice or from acinar mammary tumors from a number of mouse strains were grown in primary monolayer cultures. Such cell cultures under the influence of insulin and cortisol exhibited the ability to organize into discrete three-dimensional structures called “domes.” MTV replication in such cultures took place primarily in cells within the organized domes. Cells cultured from nonacinar tumors did not exhibit any propensity to organize into domes, nor did they replicate MTV in primary culture. This suggests that the cell organizational requirement for MTV replication observed in vivo is conserved in primary culture. Dome formation is not an effect of virus replication, as cells from uninfected BALB/c animals organized into domes in culture without concomitant MTV replication. Growth-regulating signals, exerted between contiguous cells in cultures of non-MTV-infected mammary epithelium, were not modified by the occurrence of active virus replication nor as a direct consequence of neoplastic transformation. Cells derived from nontumor BALB/cfC3H glands and from spontaneous tumors exhibited cell growth kinetics, saturation densities, and deoxyribonucleic acid synthesis kinetics nearly identical to those of noninfected normal mammary epithelium in primary culture. Cell to cell growth regulatory signals were modified in cultures of nonalveolar tumor cells wherein evidence of overgrowth is documented.

1. The pupillary phenomenon originally described by Argyll Robertson is a complex one, and consists invariably of the following components when it is fully developed: Loss of the direct and consensual response to light, retention (not invariably of normal degree) of the response to convergence, trophic changes in the texture and colour of the iris, and abnormalities in the dimensions (miosis) and in the form of the pupil. No one of these components is more constant than another, and no one of them is separable from the rest. 2. This, the true Argyll Robertson pupil, is invariably associated with neuro-syphilis, and is never found apart from that condition. 3. The Argyll Robertson phenomenon commonly develops segmentally, becoming uniform only when fully developed. It is to this segmental development of iris changes that segmental loss of light reaction and pupil irregularity are due. 4. This mode of development indicates that the underlying nervous lesion must be in the peripheral neuron. The observations recorded here are not compatible with a central lesion in the mid-brain. 5. The so-called Argyll Robertson pupil of non-syphilitic lesions of the nervous system is clinically distinguishable from the true Argyll Robertson pupil. It is accompanied by pupil dilatation, and characterized by an absence of miosis, pupil irregularity or trophic changes in the iris. Theories as to its pathogenesis have no bearing upon the problems presented by the true Argyll Robertson pupil.

Enhancement of the computing in an engineering environment by the installation of a virtual machine time-sharing system is discussed. This installation has been particularly useful in allowing the engineer to make the computer an integral part of a design cycle through the interactive use of graphic displays. Described is a CP-67 system implementing the virtual machine concept. By using an operating system of his choice in his own virtual machine, the engineering user has great flexibility in the development of applications.

SEPTEMBER 14, 1960, marked the dedication of a new ehv (extra-high-voltage) cable testing station at Cornell University. Inasmuch as the utility load doubles about every 8 years, rights of way become more difficult to obtain, and station units are larger, the need to develop 500-mva cable was foreseen in 1953.

The desire to obtain maximum yields of polyoma virus from infected mouse tissue culture lysates prompted us to examine more closely the interaction between virus and cell fragments. The objective was to find the best and most economical means of alleviating this interaction, and allow quantitative recovery of the virus for further purification. Sonication of polyoma virus infected mouse-kidney cultures sufficed to release the virus in a form amenable to hemagglutinin assay. In contrast infected mouse embryo lysates required neuraminidase to effect maximum release. A variety of other enzymes and treatments were tested and found to be completely ineffective, or less effective than neuraminidase. However, in spite of the ability to effect release of virus at this stage, subsequent centrifugation to pellet the cell fragments always resulted in reattachment of the virus to these fragments. Complete elution of the virus then required several cycles of neuraminidase, trypsin, pH 8.5 treatments. It was shown that full and empty viral capsids behaved similarly.

There has been considerable investigation in the field of cytology and since Papanicolaou'sl initial stimulating report of his experiences in exfoliative gastric cytology, efforts to improve the frequency of accurate results in this field of analysis have been intensified. We became interested in this method of study in 1948 and at that time material for examination was obtained through simple aspiration, with the aid of lavage using Ringer's solution, or after alcohol stimulation. Unsatisfactory results led us to abandon this test as a practical means of distinguishing between benign and malignant disease. Gradually, reports concerning newer methods in recovery of exfoliated gastric cells began to appear. All of these methods incorporated either the underlying principles of mucosal abrasion or of a mucolytic effect on the gastric mucous membrane, with strikingly improved results. Chief among these methods have been the development of the abrasive balloon,2 the antral abrasive balloon,3 the gastric brush,4 lavage with papain," and lavage with chymotrypsin in a buffered acetate solution.6 Throughout this survey we constantly sought one objective. We realize that by present standards of diagnosing gastric malignancy there is no necessity for another test in establishing the diagnosis in the obvious case. We hoped that a method of cytologic examination could be utilized for that group of patients whose gastric abnormalities are difficult to diagnose, and particularly in the group of patients whose malignancy is in its early phase. The results reported here indicate that while improvement has been made in the cytologic diagnosis of cancer of the stomach, we remain in accord with the general opinion that the failure to identify tumor cells by exfoliative cytologic methods does not exelude the possibility of a malignant tumor of the stomach.

Alpha-Lactalbumin was isolated from mature human milk and utilized as an immunogen in rabbits. A radioimmunoassay was developed that was capable of detecting nanogram quantities of the antigen. Alpha-Lactalbumin synthesis was detected in human breast cancer cells (MCF-7) cultivated as a continuous cell line in vitro. Other human carcinoma epithelial cell lines (throat and cervix) failed to react in this assay. The ability to synthesize alpha-lactalbumin by breast carcinoma cells appeared to be independent of the addition of prolactin to the culture medium.

Publisher Summary This chapter summarizes briefly the past literature on the studies of spontaneous mouse mammary cancer and discusses in detail the discoveries that have been made only recently. Mammary tumor studies on mice began with the first description of such tumors in a wild mouse in the year 1854. This is an area of tumor biology that was studied first by pathologists, was nurtured by geneticists and endocrinologists, and is only lately being pursued vigorously by investigators from other disciplines such as virology, immunology, biochemistry, molecular biology. Mouse mammary tumors offer many advantages for tumor biological studies. The chapter also talks about mammary tumor virus (MTV), their hormonal influences on mouse mammary neoplasia, and the two categories of inbred strains of mice employed in mammary cancer research—susceptible strains and resistant strains. The mouse mammary tumor system still remains an area of interest to researchers from different disciplines. One of the great advantages of this system remains the amenability of the host animals to laboratory experimentation.

Kinetics of cell division in cultures of Escherichia coli grown in casamino acids – glucose and recovering from short pulses of inhibition of DNA synthesis by nalidixic acid clearly demonstrates that preexisting cycles of chromosome replication continue to their ends.

It has been shown that tryptophan is not utilized in a cell-free system of Penicillium cyclopium; α-acetyl-γ-(β-indolyl)methyltetramic acid, a biosynthetic intermediate of the cyclopiazonic acids, has been identified, and the L-configuration at the asymmetric centre of the new indole established.