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D J Laurence

Publications and source records attributed to D J Laurence.

9 recordsLinked to original sources
PubMed1978

Antibodies to lactalbumin interfere with its radioimmunoassay in human plasma.

Two radioimmunoassays for human lactalbumin have been established using a rabbit antiserum. One assay uses a second antibody to separate bound from free label; the other uses polyethylene glycol to precipitate gamma globulin non-specifically. We have confirmed that about half the normal human population have a substance in their blood which inhibits the binding of lactalbumin to the rabbit antibody. Comparison of the two assays has demonstrated that this material is not lactalbumin but a naturally occurring antibody. We have shown that it is in the IgG fraction of human plasma and is probably a cross-reacting antibody to bovine lactalbumin. None out of fifteen males and fourteen out of fifty eight non-pregnant, non-lactating females had low levels of lactalbumin in the their blood (0.6--2.0 ng/ml). Our assay could not detect a statistically significant difference between normal women and those with either benign breast disease or metastatic mammary carcinoma.

Animals↗
PubMed1978

The monitoring role of plasma CEA alone and in association with other tumor markers in colorectal and mammary carcinoma.

During the past decade, evidence has accumulated to show that most, if not all, human tumors produce a variety of different factors which, if they pass into the blood and/or urine, may serve as tumor index substances (tumor markers).7 Tumor markers may either be: 1) tumor-derived--i.e., produced by the tumor itself, or 2) tumor-associated--i.e., produced by other tissues in response to the presence of the tumor and its local or distant effects on that tissue. Examples of this latter category include the changes in urinary hydroxyproline output in patients with bone metastases or the altered levels of serum acute phase proteins in neoplasia in general.7 Tumor-derived markers may be produced by either the tumor cell population itself, e.g., CEA, alpha-fetoprotein (AFP), and other oncofetal antigens, inappropriate hormones such as ACTH etc., or by their supporting framework (stroma), e.g., the osteolysins of human breast cancer.3

Breast Neoplasms↗
PubMed1977

Biochemical markers in human breast cancer.

Nineteen biochemical parameters, most of which have been individually advocated as tumour-index-substances for breast cancer, were measured in 51 patients with breast disease, 42 of whom had active breast cancer. Seven of these parameters were raised in more than half of the 17 patients of the series with overt metastases; these were serum ferritin (88%), C-reactive protein (87%), carcinoembryonic antigen (81%), acid glycoprotein (75%), total alkaline phosphatase (64%), sialyl transferase (56%), andthe urinary hydroxyproline/creatinine ratio (73%). The incidence of biochemical abnormalities in patients in this group compared favourably with the results of physical methods of detecting metastases. 7 of 16 further patients without evidence of distant metastases, but who had a poor prognosis as judged by histology of the primary tumour and axillary lymph-nodes, had abnormalities of at least one of the seven parameters. 3 of these patients have relapsed within a year of mastectomy. The results suggest that these biochemical tests could assist in monitoring metastatic disease and could indicate at the time of mastectomy, patients who might benefit from immediate systemic therapy in addition to local treatment of their breast carcinomas.

Adenofibroma↗
PubMed1975

First British standard for carcinoembryonic antigen (CEA).

In 1974, the National Institute for Biological Standards and Control (NIBSC) established the first British Standard for carcinoembryonic antigen (CEA) for use in comparative quantitative assays. The Standard, which was prepared for material processed by the Chester Beatty Research Institute, is in the form of a freeze-dried powder, sealed in all glass ampoules code labelled 73/601 and containing pure dry nitrogen. For practical purposes, each ampoule contains 100 units of CEA activity.

Amino Acids↗
PubMed1975

Human tumour-associated and tumour-specific antigens: some concepts in relation to clinical oncology.

The concept of tumour-specific antigens is constantly undergoing reappraisal with the development of more sensitive methods for their detection. This has resulted in the finding that the many 'new' antigens produced by human tumours or materials immunologically closely related to them are also present in non-neoplastic tissues, albeit in small amounts. However, other antigens still appear to exist almost entirely in or on tumour cells so that the antigens of human tumours may be subdivided into either tumour-associated macromolecules or tumour-specific antigens. The elucidation of the chemical nature of the tumour-specific antigens may result in important advances in cancer diagnosis and therapy. As many are organ specific, it should be possible to evolve test systems which will enable tumours to be diagnosed and located before they become apparent clinically. On the other hand the tumour-associated macromolecules, of which the oncofetal antigens are the principal examples, are found in elevated amounts in some non-neoplastic disorders. It is now clear that serial estimation of the levels of these macromolecules is of considerably more diagnostic value than single random measurements. Current work is establishing their value in the detection of recurrent and metastatic tumours before they become apparent by other methods, which is probably their most important role, and also their value as aids to monitor therapeutic efficacy. The future use of both types of antigen may unfold a new era in cancer detection and therapy but many basic chemical and immunological studies are needed before their clinical use can be fully defined.

Antigens, Neoplasm↗
PubMedDate not supplied

Milk proteins and mammary cancer: a review.

Milk proteins are of potential value in characterizing mammary carcinoma from a functional point of view. The major milk proteins are described with special reference to human milk. The caseins, whey proteins and membrane structures in the milk are discussed in terms of their chemical, biological and immunological properties. In vitro culture systems help to define the hormone dependency of normal mammary tissues and mammary carcinomas. The control of proliferation and milk protein production are partially independent, and this becomes especially evident in experimental tumours. Clinical samples of human tumours and plasma from patients with mammary carcinoma show differences in the level of certain milk proteins. These appear to relate to tumour spread, state of differentiation and the presence of hormone receptors.

Animals↗