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The anatomy and development of mammary tissue and the physiology of lactation show many similarities and significant differences among various mammalian species. Although the mammary glands are skin organs whose significance has been recognized for a long time, there is much new information that is reviewed in this paper. [ABSTRACT FROM AUTHOR]

Various techniques were used to obtain cell cultures from benign and malignant tumors removed from human breasts. Cell suspensions were prepared by trypsinizing finely minced tissue or by the "spilling" technique or Lasfargues and Ozzello, and T-flasks or T-flasks coated with collagen were inoculated. Trypsinized tissue yielded predominantly fibroblastic cultures, whereas those obtained by the "spilling" technique were rich in epithelial cells. The mixed cell populations were separated into pure suspensions by density gradient centrifugation. Most epithelial cell cultures grew best when they were collected by the "spilling" technique and inoculated into collagen-coated T-flasks with Eagle's medium enriched with 30% fetal calf serum. However, tears developed in the collagen coat with subsequent peeling which led to the loss of many epithelial cell colonies. Primary epithelial cells did not remain viable for prolonged periods, and attempts to obtain subcultures were unsuccessful. In this Paper the work of several investigators is reviewed and their methods of growing breast tumor cell are discussed. [ABSTRACT FROM AUTHOR]

Among the many factors that control mammary gland growth, hormones play a leading role. To assess the importance of each factor on the growth of the gland, different methods have been devised. These methods are complementary hence no method is capable by itself of a total estimate of mammary growth. Fetal growth of the mammary rudiment is influenced by hormonal factors and at the same time (more than at any other stage of mammary growth) by the mesenchyme. A marked characteristic of the fetal period is the establishment of sexual dimorphism. This peculiar phenomenon has been studied in vitro. After birth, the gland falls under the direct control of stimuli from the hypothalamus pituitary axis. By means of its cyclic variations or changes conditioned by conception, growth is induced by pituitary hormones proper (prolactin growth hormone) or via the ovary or the adrenals. Other factors such as diet, age, mesenchyme, and genetic background modulate the action of hormones on the gland. The action of all these factors is examined in this paper throughout the life of different mammals, from the prepuberal stage, through adult nulliparous life, gestation, the maximal growth induced by the hormonal levels of lactation, and in regression (produced alter hormone removal). In vivo and in vitro studies have been correlated in demonstrate which of the stimuli induce mammary cell replication and growth in the preneoplastic and neoplastic mammary gland. [ABSTRACT FROM AUTHOR]

Some of the constituents of milk are unbiquitous biochemical compounds and others are unique products of the mammary gland. Lactose, the distinctive milk disaccharide, caseins, a group of phosphoproteins, and fat are present in nearly all milks that have been examined and the pathways involved in their biosynthesis are discussed in this paper. Milks of various species differ quantitatively in the proportions of their principal constituents. These differences suggest phylogenetic grouping and undoubtedly reflect evolutionary divergence. The extent to which this divergence has been affected by the nutritive requirements of the young, by the dietary sources of the lactating female, and by various other environmental factors has not been completely clarified. Evolutionary divergence is also evident in the composition and amino acid sequences of several families of milk proteins. The relationship between such differences and the function of these proteins has not yet been elucidated. [ABSTRACT FROM AUTHOR]

The article presents news and information related to dermatology. It states that the twelve dermatological residents will compete in December 1974 for the Fifth Henry W. Stelwagon Prize presented by the College of Physicians of Philadelphia to "the resident who shall be adjudged to give the most outstanding paper" at the annual meeting of the American Academy of Dermatology. The Stelwagon Prize stems from an endowment bequeathed to the College of Physicians of Philadelphia by Henry Weightman Stelwagon, who was the first teacher of Dermatology at Jefferson Medical College, Philadelphia, Pennsylvania.

Immunofluorescent studies are currently being done on patients with pemphigus, pemphigoid, dermatitis, lupus erythematosus and its variants, the cutaneous prophyrias, scarring alopecia, erosive mouth lesions, light-sensitive disorders, and cutaneous vasculitis. In this paper I shall review some of the recent advances in immunopathology and report the results that have been obtained in our laboratory. [ABSTRACT FROM AUTHOR]

In some patients with mycosis fungoides atypical cells ("mycosis cells") are found in the blood. Recently the T-cell membrane characteristics of these atypical cells have been described. In this paper the results of a study of the atypical cells isolated from the lymph nodes and the skin lesions of three patients with mycosis fungoides are presented. Using electron microscopy, it could be demonstrated that the atypical cells formed rosettes with uncoated sheep red blood cells, but not with antibody-complement-coated sheep erythrocytes, indicating the T-cell membrane characteristics of the atypical cells. [ABSTRACT FROM AUTHOR]

Data presented in this paper show that there is no significant difference between plasma and serum vitamin B12 activity when EDTA is used as the anticoagulant. By drawing 5 ml of blood into a tube containing EDTA, the whole blood and plasma B12 activity can be measured using Lactobacillus leichmannii for the assay as the test organism. Erythrocyte B12 levels can be obtained by difference after correcting for hematocrit. Sodium heparin appears to inhibit the growth of L. leichmannii. [ABSTRACT FROM AUTHOR]

Almost from the beginning, each of the annual symposia on the Biology of Skin has been devoted to a single subject. The format has been fairly rigid: the first paper introduces the chosen subject, which is then discussed in detail in subsequent manuscripts. However, the purpose of this twenty-fifth symposium is not to pour over one cell, one organ, or one mechanism. Commemorating as it does a quarter of a century of biomedical research that was stimulated to adulthood by one man, this symposium marks a 25th anniversary and stands as a monumental tribute to biologist William Montagna.

The successful treatment of psoriasis with folic acid antagonists during the past 25 years has led to extensive research in the areas of cytokinetics and chemotherapy. In this paper we shall review selected aspects of these topics relevant to the treatment of psoriasis. The effectiveness of methotrexate treatment of psoriasis can be related to both the hyperproliferative cytokinetics of psoriasis and an increased biochemical sensitivity of psoriatic epidermal cells to this drug. Future research goals in chemotherapy of psoriasis include (a) optimizing drug schedules for available drugs; (b) identifying other susceptible biochemical points of selective drug attack; (c) identifying secondary advantages in order to facilitate selective drug action in psoriasis, such as ultraviolet light therapy in combination with a systemic drug; and (d) developing topically effective chemotherapeutic agents. Approaches. to research on topical therapy are reviewed with specific reference to animal testing models for psoriasis and percutaneous penetration of topically applied agents. [ABSTRACT FROM AUTHOR]

It was the aim of these studies to determine whether the presence of intracellular melanin quantitatively alters the rate of production of thymine dimers in DNA of irradiated cells in culture. Pigmented and nonpigmented Cloudman mouse melanoma cells were selected assuming that the two cell lines differ primarily in their content of melanin pigment. Cells were cultivated in tritiated thymine in order to label their DNA and were then exposed to ultraviolet (UV) irradiation (260 nm, 500-2000 ergs/mm²). Neither cell line survived these doses of irradiation. DNA was extracted immediately following irradiation and was subjected to acid hydrolysis. The presence of thymine dimers was determined by two-dimensional paper chromatography. The percent of labeled thymine recovered as thymine dimer was calculated and was found to be a linear function of UV dose for both cell lines. The rate of formation of dimers in the nonpigmented cells was nearly twice that in the pigmented cells. These data demonstrate the photoprotective property of intracellular melanin in shielding isolated cells from one type of photomediated injury to DNA. [ABSTRACT FROM AUTHOR]

The article presents abstracts of papers to be presented at the symposium to be held on December 7, 1976, at the Annual Meeting of the American Academy of Dermatology, at the Palmer House, Chicago, Illinois in association with The Society for Investigative Dermatology Inc. Oral psoraleri photochemotherapy (PUVA) has been used for over two years in the treatment of psoriasis with good results. Because sunlight or artificial UVB is sometimes beneficial to patients with eczema, the effect of PUVA on eczema has been investigated.

Fifty-two children, age 5-10, from acne-prone families, were studied for a period of 1 year to examine the interrelationship between sebum, acne, pubertal development, and urinary steroid excretion. In each of the subjects, 30 boys and 22 girls, the composition of forehead skin lipid was determined 4 times yearly by thin-layer chromatography, with measurement of triglycerides, diglycerides, free fatty acids, wax esters, squalene, cholesterol, and cholesterol esters. Twice yearly, examination was made of the presence or absence of acne, pubertal maturation and the 24-hour urinary excretion of testosterone as determined by radioimmunoassay, and of total 17-ketosteroids, dehydroepiandrosterone, androsterone, and etiocholanolone, as determined by paper chromatography. The relative amount of sebaceous lipids was positively correlated with age of the subjects (wax esters p < .001, squalene p < .05), as was the triglyceride-diglyceride component (p < .05). No significant correlation was seen with the fatty acids. Acne, primarily comedonal, occurred in 27/52 subjects (15 girls, 12 boys) and was associated with higher sebum values. One-half of the children with acne had no signs of pubertal development. A significantly positive correlation was observed between the relative amount of sebaceous lipid and the urinary excretion of 17-ketosteroids, androsterone, and etiocholanolone in both sexes, and of testosterone and dehydroepiandrosterone in boys. The development of acne in children is an early pubertal event, often evident before other signs of pubertal maturation, and it is associated with an increase in sebum and in the urinary excretion of androgenic steroids. [ABSTRACT FROM AUTHOR]

This article reports on a research conference of the European Society for Comparative Skin Biology, that will be take place at the University College Hospital Medical School, University of London, England from September 19-22, 1978. The meeting will include papers on the cell structure and function, permeability and barrier function, and control mechanisms. There will be discussion group sessions on mucogenesis, cell growth and proliferation, and keratinization.

Langerhans cells constitute a minor cell population within the mammalian epidermis. This paper defines these cells immunologically and functionally and supports the concept that Langerhans cells are closely related to cells from the monocyte-macrophage-histiocyte series. Both cell types bear surface receptors for Fc-IgG and C3 and express surface glycoproteins, termed Ia antigens, encoded for by immune-response genes (Ir genes) of the major histocompatibility complex of the species. The expression of Ia antigens by Langerhans cells and macrophages is intimately associated with important functions of both cell types, including the capacity to present immunologically relevant antigen to the T lymphocyte and to cause proliferation to allogeneic T lymphocytes in mixed leukocyte reactions. [ABSTRACT FROM AUTHOR]

Basophilic leukocytes constitute a significant proportion of the cellular infiltrates in many forms of delayed-in-onset hypersensitivity reactions in human beings, guinea pigs, and other animals. In this paper, I review current information on the role of basophils in the reactions, and present similarities and differences between Jones-Mote and classic delayed hypersensitivities. [ABSTRACT FROM AUTHOR]

The article givesa information on proceedings of the First International Workshop on Vitiligo. The first International Workshop on Vitiligo was held at the National Institutes of Health, Bethesda, Maryland, on March 3-4, 1977. Dermatologists and pigment cell biologists from several countries gathered to share their ideas on vitiligo, to review known facts about the disease and its treatment, and to make recommendations for further investigations.The first series of papers dealt with the biology of pigment cells and the relationship of cell function to vitiligo. Vitiligo as a disease process deserves to be studied vigorously because current therapy is far from successful and because the disorder is a major problem for affected persons.

Although there has been much discussion in recent years of the applicability of mathematical methods in the social sciences, little attention has been paid to the interaction of the sociological analysis and the mathematics. In this paper, an example of an extremely fruitful interaction between anthropology and mathematics is described. The interaction has, on the one hand, greatly increased the subtlety and sophistication of the sociological analysis, while on the other hand it has posed interesting mathematical questions. [ABSTRACT FROM AUTHOR]

This paper presents a generalization of the concept of "structural equivalence ", the key concept in algebraic approaches to the study of social networks. Two points in a graph or set of relations will be called "structurally related" if they are connected in the same ways to structurally related points. It is suggested that this new definition suitably weakens Lorrain and White's categorical approach, and is more appropriate than CONCOR. Structural relatedness is compared to these approaches via several simple examples. [ABSTRACT FROM AUTHOR]

Protein requirements in maintenance hemodialysis patients are still unclear. Based on nitrogen balance studies and different analyses of protein and amino acid metabolism, the recommendations until recently were 1 g/kg of body weight, primarily of high biological value protein. According to the results of controlled long-term studies the 1 g recommendation now seems too low. The paper reports on the results of a controlled study undertaken to define protein requirements. The effect of supplementation with a special protein mixture is studied on the basis of 1 g of protein per kilogram of body weight intake and about 20 hr standard dialysis per week. The results suggest that 1.2 g of protein per kilogram of body weight primarily of high biological value protein and 35 kcal/kg of body weight should be prescribed for dialysis patients. In case of complications (bleeding, infection, and other stress situations) additional supplements are necessary. [ABSTRACT FROM AUTHOR]

Anaerobic, gram-negative, nonsporing rod-shaped bacteria that digest wet-ball-milled filter paper have been isolated in numbers of over 108 per gram wet weight of feces, about 0.3% of total viable bacteria, from feces of two humans. Significant numbers of cellulolytic bacteria were not detected in four other humans. One of the strains is a Bacteroides sp., which only slowly digests cellulose and produces succinate, acetate, and H2 in carbohydrate fermentation. [ABSTRACT FROM AUTHOR]

This paper is an attempt to examine and define the world network of a typical individual by discovering how many of his or her acquaintances could be used as first steps in a small-world procedure, and for what reasons. The town and occupation of each target was provided, together with the ethnic background, where this could not be inferred from the name. Starters were instructed in the small-world experiment and asked to write down their choice, amongst the people they knew, for the first link in a potential chain from them to each of 1267 targets. Starters provided information on each choice made (e.g. mother, cousin, friend, acquaintance, etc.) together with the sex of the choice) and the reason that choice had been made. The reason could be in one or more of four categories: something about the location of the target caused tile starter to think of his or her choice; the occupation of the target was responsible for the choice; the ethnicity of the target; or some other, unspecified, reason. Six main conclusions may be drawn from the data: (1) A mean of 210 choices per starter account for the "world" (i.e. the 1267 targets). This number is probably an underestimate. Only 35 choices are necessary to account for half the world, however, Of the 210, 95 (45%) were chosen most often for location reasons, 99 (4 7%) were chosen most often for occupation reasons, and only 7% of the chokes were mainly based on ethnicity or other reasons. (2) Chokes were mainly friends and acquaintances, with strong cleavage by sex. For any given target, the type of choke used by the majority of starters was a friend or acquaintance, and not family. For any given target, the most likely sex of the choice (i.e. over all starters) can be predicted accurately on 82% of occasions. This sex tends to be male, unless both starter and target are female, or if the target has a low-status occupation. Additionally, any given starter is most likely to pick a male choice for any target, except for the female starter-female target combination, when female choices are more likely. This was correct on 64% of occasions. (3) Location was the usual reason for choice (out of the four categories), with occupation second, and ethnicity or other reasons rarely used. This most popular reason for choice may be correctly predicted for any given target 81% of the time. (4) The decision as to which choke was made appears to depend primarily on the occupation of the target, and secondly on the distance (near/far) from Morgan town, West Virginia, where the experiment took place. (5) The expression "having one's man in ..." can be partially quantified. We may define a choke to "handle" a state in the U.S. if he or she was chosen for two-thirds or more of the targets in that state for which choices were made on the basis of location. Then, for any starter, on average, half the states are each handled by a single choice. (6) The accuracy of starters' recall about their networks is low, in the sense that their recall is incorrect more often than it is correct (i.e. their recall could not be put to any other use with any reliability). This confirms previous experiments on informant accuracy. [ABSTRACT FROM AUTHOR]

This paper poses two questions about the process of friendship formation: what is the relative stability of asymmetric and mutual friendship dyads and what is the nature of change in asymmetric dyads over time? These questions are examined in longitudinal sociometric data from five elementary classes. Change in friendship choices is shown to be at least partially embeddable as a continuous time, stationary Markov process and the unique Q matrices governing the process are determined. The findings show that unreciprocated friendship choices of the children in the sample are less stable than reciprocated choices and that their unreciprocated choices tend to be withdrawn rather than reciprocated over time. [ABSTRACT FROM AUTHOR]