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This paper describes further confirmation of the successful application of the macrophage electrophoretic mobility (MEM) test to the detection of malignant disease. Results from fifty-one patients and eighteen controls are presented. The apparatus and technique used for the measurement of macrophage elctrophoretic mobility differed from those previously used in other investigations. Further information is presented on the nature and behaviour of macrophage slowing factor(s), and experiments concerning the possible use of cells other than guinea-pig macrophages as indicators of slowing factor production are also described. [ABSTRACT FROM AUTHOR]

There is considerable evidence that electrolytes can penetrate the stratum corneum but there is no evidence on whether this penetration occurs through or between the corneum cells. In this paper evidence is presented which shows that the equilibrium water content of intact corneum immersed in electrolyte solutions depends upon the electrolyte concentration and obeys the laws of osmosis. Removal of lipid by solvent extraction destroys the osmotic properties. This evidence indicates that the osmotic properties of corneum depend upon the presence of a lipid-containing semipermeable membrane system. Other evidence indicates that this membrane system is the cell walls of the corneum cells themselves. If electrolytes cannot enter the corneum cells in these osmotic experiments it follows that they cannot enter the corneum cells during penetration through the stratum corneum and that they must therefore pass between the cells. [ABSTRACT FROM AUTHOR]

In a case of pyoderma gangrenosum without associated disease, clumping of cells was noted during routine leucocyte counts. It was probably due to a cryoglobulin in the patient's plasma. [ABSTRACT FROM AUTHOR]

The article focuses on the physiological prerequisites required for the transition of autotrophic plants from water to terrestrial life. It is stated that the presence of cells with central vacuoles seems to be a prerequisite for invasion of land by plants. An inner aqueous medium is provided by their cell sap which determines the status of protoplasmic hydration. There is an reemphasis of the fact that the protoplasm is the site of all vital processes. Therefore, it is important to study the hydration of protoplasm.

The article discusses the paper "The Problem of Cellular Naevi," by C. Voss. This paper concludes that the cellular naevus is a complex neurogenic malformation, of neuroectodermal and neuromesodermal origin. Dendritic chromatophores and dendritic cells belong to the same system.

Freshly harvested epidermal cells from the dorsal skin of albino guinea-pigs have been cultured for several days on glass slides and on collagen films within Leighton tubes. Routinely it has been observed that the keratinocytcs which initially attach to the substratum rapidly detach again during the first 6 days and the presence of collagen does not influence their overall survival. However, the keratinocytes cultured on collagen films exhibit greatly enhanced cellular metabolism, in particular, dehydrogenase activity, DNA synthesis and phospholipid turnover. These findings support those published by others that collagen (and, presumably, other components of dermis) greatly influences the epidermis in vitro. [ABSTRACT FROM AUTHOR]

Two out of sixteen biopsies from verrucous lesions of xeroderma pigrnentosum revealed unusual electronmicroscopic changes. Structures resembling anchoring fibrils and the basal lamina were noted within the grossly dilated rough endoplasmic reticulum of some basal and suprabasal keratinocytes. [ABSTRACT FROM AUTHOR]

Biopsies from affected skin of sixty-two patients with stable psoriasis were investigated by in vitro labelling with tritiated thymidine and by routine histological techniques. In the same patient there were considerable variations in the number of DNA-synthesizing ceils in biopsies taken from different but similarly located lesions of the same macroscopic appearance, whereas variations in the number of DNA-synthesizing cells in biopsies taken from the same lesions were less pronounced. With due regard given to this finding, it is shown that treatment with dithranol for I and 2 weeks significantly reduces the number of DNA-synthesizing cells. There was an inverse relationship comparing the development of the granular layer with the number of DNA-synthesizing cells and parakeratosis. The variations in the number of DNA-synthesizing cells in different lesions in the same patient may also have implications for paired comparisons of topical treatment efficiency. [ABSTRACT FROM AUTHOR]

A quantitative in vitro method for phytohaemagglutinin (PHA) induced lymphocyte transformation is described. This method has the following advantages. Cultures require as few as 105 lymphocytes and are performed in microtrays, over a short incubation period (48 hr). A short pulse time of 4 hr with [³H] thymidine is utilized. This enables high levels of [³H]thymidine to be maintained throughout the labelling period, ensures maximum incorporation of thymidine into cellular DNA, and diminishes cellular damage by internal irradiation. The extraction process has been simplified by using a communal washing procedure after drying the cultures on glass-fibre filter discs. The procedure is both quicker and more reproducible (coefficient of variation 6%) than extraction and drying on filtration manifolds (coefficient of variation 23%). The effect of adjusting variables such as the number of cells, incubation time, concentration of [³H]thymidine, concentration of PHA, specific activity of [³H]- thymidine and duration of [³H]thymidine pulse has been studied in order to approach optimal labelling conditions for the assay system. The reproducibility of the method has been investigated by repeated testing of normal individuals on a day-to-day basis and over extended periods. The mean coefficient of variation for samples repeated daily and over longer time intervals (weeks or months between samples) was 15%. [ABSTRACT FROM AUTHOR]

Guinea-pigs made tolerant to dinitrochlorobenzene (by prior intracardiac injection of dinitrobenzene sulphonate) failed to give positive skin reactions after contact sensitization, but nevertheless had peritoneal cells which reacted with the hapten in macrophage migration inhibition (MMI) tests. This reactivity was blocked in vitro by the addition of serum from tolerant animals but not by serum from hyper-sensitive animals. Cells from hypersensitive guinea-pigs were anomalous, in that their reaction with hapten in MMI was not blocked by tolerant serum. Hypersensitive serum, though not active by itself in MMI, was able to prevent blocking by tolerant serum when the two sera were mixed. This was interpreted as an `unblocking' phenomenon and suggested that hypersensitive cells were insusceptible to blocking because they themselves produced an unblocking substance (antibody ?), although preliminary efforts to demonstrate this directly were not successful. Hypersensitive serum had an analogous activity in vivo, since when passively transferred to otherwise tolerant animals it enabled them to produce typical skin reactions; that is, it broke tolerance. Tolerance or non-reactivity in vivo in the situation investigated thus appears to be an enhancement-like process, characterized by the presence of reactive lymphoid cells and a blocking factor (antigen-antibody complex?) detectable in the serum of the tolerant animals. [ABSTRACT FROM AUTHOR]

The epidermal component of lichen planus seems to result from a continuous process of erosion of the basal zone, and repopulation of the `wounded' area by cells from nearby uninvolved epidermis. In order to investigate these migrating cells further, we have studied tissue slices from forty papules of lichen planus derived from twenty-nine patients. The tissue slices were cultured for periods of 24 or 48 h. Marked migration of fusiform and spindle-shaped cells into the eroded dermo-epidermal zone appeared to have taken place. In general, the changes represented an exaggeration of those usually present in vivo. Cytochalasin B, in concentrations of 5 μg/mI or greater in the culture medium, prevented cell migration. This effect, and the fact that autoradiographic studies showed few cells to be synthesizing DNA, suggested that cell migration took place by movement rather than by mitotic activity. [ABSTRACT FROM AUTHOR]

On the basis of a detailed case report it is suggested that a distinctive dermatosis is specifically associated with a tumour of pancreatic alpha cells. [ABSTRACT FROM AUTHOR]

The article presents information on the paper "Qualitative and Quantitative Data on Melanocytes in Human Epidermis Treated With Thorium X," by R.J. Staricco that appeared in the 1957 issue of the "Journal of Investigative Dermatology." Researchers found that in skin reacting mildly to thorium X, the melanocytes exhibit increased activity, send out long processes and may even ascend the outer layer and be desquamated, but they do not increase numerically out of proportion to the basal cells.

The article focuses on the research paper "Senile Keratoses and Intraepidermal Epitheliomas," by G. Achten. The authors have studied 112 biopsies of senile keratoses and classified them according to findings in precancerous lesions of the cervix uteri. Their results show that 42% showed simple abnormality of the epidermis (thickening without cellular changes), 27% showed aggravated abnormality (thickening with loss of regularity of arrangement of cells and with cell nests but little or no alteration in the cells themselves) and epithelioma in situ.

The article presents an abstract of the paper "The Treatment of Alopecia With Fresh Pituitary Cells," by H. Flegel. The author comes to the conclusion that treatment of alopecia by intramuscular injection of suspensions of calf's pituitary in saline with the addition of penicillin is not superior to other forms of treatment and should be abandoned.

This article focuses on the paper "Histological Chemical States of the Human Skin: The Cellular Spaces," by A. Dupre that was published in a 1953 issue of the periodical "Annals of Dermatology and Syphilology." Using the MacManus stain and other reactions the author demonstrates a complex lipo-glycoprotein body corresponding to the cement substance between epidermal cells.

The article offers information on the research living cells grown in tube. A research was conducted at the National Institutes of Health in the United States, of devising an artificial circulatory network that allows them to grow living animal cells in the laboratory to density that resembles natural body tissue. Scientists involved to the research include Richard A. Knazek, Peter O. Kohler, and William R. Kidwell. With the research many types of human and animal cells can be grown in the test tube.

The development of cell-mediated immunity to paternally-derived foetal transplantation antigens in parous mice has been assessed by two techniques: skin grafting in an H-2 incompatible mating and a local graft-versus-host assay in an H-2 compatible mating. (1) Lymphoid cells from BALB/c females, parous one to seven times to C3H/Bi males, were injected i.p. into syngeneic males or females which were then grafted with skin from the paternal strain. A slightly accelerated rejection in the adoptively immunized recipients was observed. (2) Lymphoid cells from CBA females, parous one to five times to AKR males, were injected into the feet of young F1 hybrid recipients. The degree of popliteal lymph node enlargement was significantly greater in recipients of cells from parous than from virgin donors. Results using both techniques demonstrated that the development of cell-mediated immunity to paternal transplantation antigens is a regular feature in parous mice and that the degree of immunity increases with successive interstrain pregnancies. [ABSTRACT FROM AUTHOR]

A 51Cr in vitro system was used to study the influence of cyclophosphamide on: (1) The capacity of rat lymphocytes to destroy allogeneic kidney cells. (2) The formation of enhancing and cytoaggressive antibodies. (3) The sensitivity of allogeneic rat kidney cells to an attack from lymphocytes and/or antibodies. It was found that : (1) Lymphocytes from a non-immunosuppressed transplant recipient rat had a clear ability to destroy the allogeneic kidney cells. (2) Serum from a non-immunosuppressed recipient rat without complement had a slight blocking or enhancing effect. (3) Antibodies capable of exerting a cytoaggressive action on allogeneic kidney cells together with complement were produced in non immunosuppressed recipient rats. The amount of these antibodies diminished when cyclophosphamide was given. (4) Cyclophosphamide treatment diminished the number of white blood cells and the number of lymphoid cells in the thoracic duct. When the same number of thoracic duct cells as in the non-immunosuppressed group was used about the same cytoaggressive effect occurred. Thus cyclophosphamide had a 'quantitative' but not a 'qualitative' depressive effect on cell bound immunity. (5) Cyclophosphamide treatment had no effect on the enhancing activity in serum. No differences were found between transplanted and non transplanted target kidney cells. [ABSTRACT FROM AUTHOR]

It is known that after mixed culture lymphocytes exhibit an increase in cytotoxicity to a target cell. The present study was undertaken to see if the degree of cytotoxicity was also related to HL-A differences. A cytotoxic effect was found where there was antigenic disparity. The degree was unrelated to the number of different antigens at the HL-A locus but cytotoxic effect was absent in cultures where there was complete HL-A identity using lymphocytes from twins, siblings and unrelated persons. [ABSTRACT FROM AUTHOR]

Eight-week-old pigs fed a protein-rich diet ad libitum developed an abnormal intestinal microbial flora within 1 week. The main feature was a significant increase in the number of atypical Clostridim perfringens, type A. In the first week after the change of diet, the pigs showed disturbances of movement and swollen peripheral joints. The ESR was concomitantly elevated and later on hypergammaglobulinaemia with increased antibody titres to Cl. perfringens antigens were noted. Joint deformities were observed after some months. The joint lesions consisted of synovitis with a cell-rich exudate. The lesions of the synovial tissue were characterized by proliferation of the synovial lining cells with villous hypertrophy and highly vascularized granulation tissue containing accumulations of lymphoid cells. Pannus formation and erosion of joint cartilage were seen in some animals. Bacteriological examination, including search for mycoplasmas, was negative. Subcutaneous nodules of rheumatoid nature were also found. Signs of proliferative glomerulonephritis were demonstrated in most of the animals. Different pathogenic aspects are discussed with regard to the direct influence of Cl. perfringens antigens on the joint tissues, circulating antigen-antibody complexes and cell-bound antibodies. As the same abnormal intestinal flora and immunological reaction to intestinal Cl. perfringens have been found in human rheumatoid disease, this diet-induced pig arthritis of remarkably similar clinical and histological characteristics is of special interest. [ABSTRACT FROM AUTHOR]

Mice were rendered specifically unresponsive to picryl chloride by pretreatment with picryl sulphonic acid. These mice fail to develop contact sensitivity, as judged by increment of car thickness, when, subsequently sensitized on the abdomen and challenged 6 days later with picryl chloride on the car. These mice were not in a pure state of classical immune tolerance. This was shown in two ways. (1) Cells from unresponsive donors were injected intravenously into normal CBA mice. The mice were then sensitized on the same day and challenged 6 days later. 'Unresponsive' (but not a variety of control) lymph node cells impaired the development of contact sensitivity to picryl chloride. The impairment was immunologically specific and 'unresponsive' cells did not impair the development of contact sensitivity to 'oxazolone'. (2) Unresponsive mice were irradiated and restored with 'unresponsive' bone marrow cells. They regained immune competence to picryl chloride when injected with normal lymph node cells and sensitized on the same day, and failed to regain competence when injected with unresponsive lymph node cells. The distinctive finding was that the injection of a mixture of normal and unresponsive lymph node cells failed to restore immune competence. Similar results were obtained when irradiated but otherwise normal recipients were used. Unresponsive cells also impaired the passive (adoptive) transfer of contact sensitivity. These results show that lymph node cells from mice which are unresponsive to picryl chloride actively and specifically impair the induction or manifestation of contact sensitivity to picryl chloride. It was concluded that this form of unresponsiveness is not classical tolerance and the hypothesis is put forward that the unresponsiveness is due at least in part to antibody mediated depression of contact sensitivity. [ABSTRACT FROM AUTHOR]

A technique is described for the detection of immunoglobulins secreted by individual lymphoid cells. Cells were cultured. in agarose gel containing dilute radio- labelled anti-immunoglobulin antibodies. The secreted immunoglobulins produced a precipitin lattice which was made visible by washing the gel, followed by autoradiography. Immunoglobulin secreting cells were surrounded by clusters, or 'galaxies' of silver grains. Galaxies did not appear in the presence of certain metabolic inhibitors, indicating that the secretion of immunoglobulin was an active process dependent upon cell metabolism. [ABSTRACT FROM AUTHOR]

Macrophage migration inhibition has been induced with cultures of normal guinea-pig peritoneal exudate cells and mitochondrial antigen of guinea-pig liver. The effect, like the antigen induced phenomenon, is prevented by exposure to trypsin. Puromycin and cycloheximide in contrast did not prevent macrophage migration inhibition. The migration inhibition was compared with the results of skin tests and with passive haemagglutination and immunocyto-adherence tests using liver antigen coated cells. Only the latter test was positive. The migration inhibitory effect is considered. in relation to cell-mediated immunity to tissue antigens and its possible role in localization of macrophages in the inflammatory response. [ABSTRACT FROM AUTHOR]

An experimental system is described, based on the use of 51Cr-labelled L cells, permitting the measurement of cell detachment and of 51Cr release by cells. This system is used to quantify detachment of, and 51 release by L cells subjected to normal mouse spleen cells. A detachment of L cells is thus observed. It is mediated by (a) soluble factor(s). It may be produced by normal non-immunized non-stimulated lymphocytes, but non-lymphoid nucleated cells may have the same effect. It is increased by heparin and Trypan blue. Possible implications of these observations for the interpretation of results of experiments on cell-mediated cytotoxicity are discussed. [ABSTRACT FROM AUTHOR]

The mechanism of immunological tolerance of sheep red blood cells (SRBC) in mice treated with a single dose of cyclophosphamide was studied. Specific tolerance lasted for as long as nine months in some animals, and its maintenance required the repeated administration of SRBC. Anti-SRBC antibody-forming cells were significantly reduced in the tolerant mice, and X-irradiated recipients of their ere specifically tolerant of SRBC. The smallest number of SRBC required for induction of tolerance was 107 this was the smallest number of SRBC that could elicit antibody synthesis within 5 days in normal mice. Since the effects of cyclophosphamide on antibody-forming cells last only 5 days, it was concluded mechanism of tolerance induction involved destruction of antigen- stimulated cells. In support of this is the finding that mice treated with small doses of cyclophosphamide were rendered tolerant only when SRBC were given before the drug. Drug-induced immunological tolerance thus appears to differ significantly from both pneumococcal polysaccharide paralysis and classical, acquired tolerance. A central loss of immunocompetence does not occur in the former, while the latter requires for its induction the administration of antigen in a dose or form that does not stimulate antibody synthesis. [ABSTRACT FROM AUTHOR]

gThe article states that electrophoretic mobility of peripheral blood lymphocytes from human subjects with positive Mantoux tests was measured before and after treatment with purified protein derivative. Lymphocytes from subjects with negative Mantoux reactions were used as controls. A large number of the first group lymphocytes showed a reduction of electrophoretic mobility and hence of the surface electrical charge. The mobility of the control cells submitted to the same treatment was unchanged. The possible presence of cytophilic antibodies or of cellular specific receptors on the lymphocyte surface is discussed.

The article presents information on a study which describes immunoglobulin G antibody to parathyroid oxyphil cells in the serum of one of nine patients with idiopathic hypoparathyroidism. This serum also reacted with the chief cells of the parathyroid. A limited number of unfixed frozen sections were obtained from a small parathyroid adenoma from a female patient aged 42 years with hyperparathyroidism. Immediately after the removal of the adenoma from the patient, the tissue was rapidly frozen and the sections prepared.

The article presents information on an immunological study of maple bark disease. The immunological response of three groups of guinea-pigs to the spores of Cryptostroma corticate (C. corticate) was studied. The first group received spores only intradermally (i.d.) and all of eleven developed precipitating antibody and ten out of eleven developed a positive skin reactivity. The second group received the spores i.d. and were exposed to an airborne suspension of the spores. The skin reactivity was maximal at 24 hour and could be passively transferred with buffy coat cells but not with serum. This supports the hypothesis that there is a delayed hypersensitivity phenomenon in maple bark disease.

The article presents a discussion related to prednisolone and gastric atrophy. Eight patients with Addisonian pernicious anaemia were given 20 mg of prednisolone daily for up to 20 weeks. Improvement in absorption of vitamin B12 as judged by the Schilling test occurred in six cases and was pronounced in four, and there was increased secretion of gastric intrinsic factor in four cases. Gastric biopsies showed regeneration of specialized gastric glands in four cases; chief cells were demonstrated histochemically and parietal cells by an immunofluorescent procedure using serum containing parietal cell antibody.

The article reports on a recent study in which the effect of neonatal thymectomy and antigenic stimulation on the lymphoid cell population has been studied in germ-free mice. It was found in the study that thymectomy did not influence the cellularity of the lymphoid follicles but less germinal centre and plasma cell activity occurred in response to an injection of sheep erythrocytes. Lesions suggestive of autoimmune reactivity were not found in lymphoid or nonlymphoid tissues of neonatally thymectomized germ-free mice.

This article reports that The antibodies were present in the IgG globulins, in the IgM globulins also in nearly 50% of the IgG-positive crises and rarely in the IgA globulins. One-third ofthe antibodies proved to be complement-fixing. No antibodies were found in normal controls matched for sex and age. No correlation was demonstrated between antibodies to salivary duct cells and any of the other antibodies mentioned. Antibodies to salivary duct cells could only be absorbed with salivary gland tissue and not with other-tissues.

Epidermal cells migrate from the edges of adult human skin in culture during the first 48 h. In order to determine whether mitotic activity was responsible for this cell movement the autoracliographic labelling index for cells in DNA synthesis was determined for skin at different stages of culture. The labelling index of skin maintained for 48 h but labelled with tritiated thymidine in the first 4 h, did not differ significantly from skin both maintained and labelled for 4 h only. Skin maintained for 48 h but labelled in the last 4 h showed a much lower labelling index. No normal mitotic figures were seen in the epidermis of skin maintained for 48 h but exposed to colcemid for the last 4 h of culture. It has been concluded that at Least in short-term organ culture of adult human skin there is a phase of mitotic arrest and that epidermal migration during the first 48 h is an active process independent of mitotic activity. [ABSTRACT FROM AUTHOR]

The rate of epidermal cell proliferation has been examined by autoradiographic methods in lichen simplex chronicus in sixteen patients. The corrected labelling index was found to be 25.9% in eleven biopsies removed 50 min to 1 h after intracutaneous injection of tritiated thymidine (i.e. similar to that in psoriasis). Twelve biopsies were removed 1-8 days subsequent to injection with tritiated thymidine, and in the autoradiographs that resulted it was found that the rate of travel of labelled cells was not fast as in psoriasis. The possible explanations for the finding of a labelling index similar to that of psoriasis but a slower transit time include; the presence of a greater epidermal volume in lichen simplex; the inclusion of 'high level labelled cells' in the labelling index; and epidermal damage from the trauma of scratching resulting in intra-epidermal cell death of labelled cells. [ABSTRACT FROM AUTHOR]

Rat dorsal skin was fractionated by means of an electrokeratotome into epidermis and dermis containing the sebaceous glands. These fractions were separately cultured in the presence of 32P-orthophosphate, 14C-acetate, 14C-glycerol and 14C-mevalonate, and the radioactivity incorporated into different classes of lipids was measured. The nature of the labelled products was different in the epidermis compared with the sehaceous glands: in the former, phospholipids and sterols were the major radioactive lipids synthesized, whereas, in the sebaceous glands labelled triglycerides, sterol esters and wax esters predominated. The nature of individual fatty acids labelled from 14C-acetate was studied and it was found that the sterol/wax esters fractions of both epidermis and sebaceous glands contained more radioactive odd-numbered normal chain and iso- and anteiso-branched chain fatty acids than the phospholipids and triglycerides. Isolated epidermal cells were prepared, and lipogenesis studies with radioactive precursors showed labelling patterns very similar to those of the cultured intact epidermis fractions. The presence of biochemically active sebaceous glands in the dermal residues, after excision of the epidermis fractions, was confirmed by treating skin in vivo with methyl testosterone, a hormone which stimulates the function of sebaceous glands, when a higher rate of lipogenesis was observed in the subsequently cultured dermal residue fractions, compared with untreated controls. No such differences were seen in the epidermis after testosterone treatment. [ABSTRACT FROM AUTHOR]

The effects of 2-bromostearic acid, 2:4-dinitrophenol and menadione on the respiration of skin slices in the presence or absence of added glucose was measured. All 3 compounds depress endogeneous respiration, whereas in the presence of added substrate, 2-broinostearic acid has no effect and 2:4-dinitrophenol and menadione stimulate respiration. Since cells in the upper part of the epidermis are in a glucose-free environment, it is suggested that in vitro tests of potentially toxic substances should be performed both in the presence and in the absence of glucose. [ABSTRACT FROM AUTHOR]

A study has been made of 34 cases of fibrous papule of the nose presenting at St John's Hospital for Diseases of the Skin in the past decade, Histologicai sections from biopsies of these lesions were examined and compared with lesions of juvenile melanoma and naevus cell naevus arising on the face. In 2 patients fibrous papules were investigated by enzyme histochemical methods. Fibrous papules were usually single small nodules on the nose, often simulating angiomata, moles or pyogenic granulomata. The sexes were equally affected and most of the patients were in the third to the fifth decades. Although these lesions were not distinctive clinically, histologically they presented a characteristic appearance, which included a distinctive fibrovascular component composed of broad bands of connective tissue orientated at right angles to the surface and interspersed with multinucleate cells and undoubted naevus cells, and an increased number of epidermal clear cells. A marked decrease in the elastic staining properties of the dermal connective tissue was characteristic of these lesions as was increased staining with P.A.S, The available evidence, including the enzyme histochemical findings, is consistent with this lesion being a member of the naevus cell spectrum of disorders. [ABSTRACT FROM AUTHOR]

Attention is focused on an excretory function of the epidermis, for which the term ‘catharsis’ is proposed. In this context, the epidermis is viewed as an organ participating actively in the percutaneous elimination of materials from the system. This phenomenon involves the phagocytic activity of epidermal cells, selective uptake, and epidermal proliferation. The particular modus operandi is conceivably dependent on the size and nature of the material to be disposed of. Phagocytosis is operative in certain pathological conditions such as cutaneous leishmaniasis. Selective epidermal uptake occurs in the elimination of certain chemicals. Epidermal proliferation, engulfment and eventual trans-epithelial elimination is seen in elastosis perforans serpiginosa, reactive perforating collagenosis and calcinosis cutis. This mechanism is also observed to a certain extent in the skin lesions of a variety of other conditions such as tuberculosis and North American blastomycosis. The phenomenon of catharsis is regarded as another feature of the intimate dermo-epidermal interplay and interaction. Some of the factors involved in this interaction are reviewed. [ABSTRACT FROM AUTHOR]

59Fe-ferric citrate was injected into the skin of 23, normal subjects and 6 iron deficient patients. Iron clearance, measured by external scintillation counting, could be resolved into 3 exponential components. The first, rapid component resulted from the removal of unbound iron by the blood stream. A lymphatic component, t1/2 23.9 hr., accounted for; the clearance of two-thirds of the transferrin bound iron from the skin of normal subjects; the remaining one-third was taken up by the epidermal cells arid cleared only slowly (t1/2 67 days) from the injection site; This pattern was not altered by binding the iron to plasma before injection but in the anaemic iron, deficient patients over half of the transferrin bound iron was taken up by the cells. The possible causes of the increase in the epidermal- component in the iron deficiency are discussed. [ABSTRACT FROM AUTHOR]

The article focuses on the effects of neutrophils on tissues. Neutrophils are the first cells to infiltrate damaged tissue and continue to do so as long as it persists. Much of the damaged tissue is digested extracellularly by enzymes liberated from the neutrophils accumulating in the tissue. If the foreign material is toxic, susceptible tissues are thereby protected at the expense of the phagocyte. Lysosomes contain the enzymes required to digest substances taken up by all living cells but whereas in most cells the substances ingested are normally those required for cell metabolism, phagocytes ingest and digest foreign material.

The method of exhibiting the layers of cells of the stratum corneum described by Kligman and Christophers has been employed and elaborated, and has proved to be practical and reproducible. The cells can be counted and observations made on their morpbology. The shape of the cells treated by this method has been shown to be different at various sites and at different levels of the stratum corneum, and in patbological states. The stratum corneum is probably more compact than bas been hitherto supposed. Differences in susceptibility to alkali have been demonstrated in the horny cells surrounding the eccrine sweat ducts and the pilosebaceous orifices. There are also age differences in the susceptibility of the stratum corneum to alkali and possibly in its thickness. [ABSTRACT FROM AUTHOR]

Staining of the human stratum corneum in vivo with fluorescent tetrachlorsalicylanilide has been used to measure the transit time of horny cells in the normal forearm skin of aged people. Stratum corneum thickness was estimated by counting the horny cell layers in biopsy specimens of epi - dermis, visualized by hydration in alkali. From the two parameters thus obtained, stratum corneum replacement rates were calculated. In 6 aged men, transit times varied between 20 and 36 (mean 26) days, and replacement rates between 30 and 47 (mean 34) hr. per cell layer. These data suggest reduced epidermal mitotic activity compared with that of young men. In 5 aged women, transit times varied between 17 and 26 (mean 20) days and replacement rates between 16 and 31 (mean 24) hr. per cell layer. This faster replacement in old women compared with old men is not much slower than that observed in young adults. [ABSTRACT FROM AUTHOR]

Fixation of the normal epidermis in osmium tetroxide followed by passage of the tissue through solvents to paraffin wax for light microscopy results in a different appearance of the horny layer compared with that after formalin fixation. Osmium fixed horny cells appear solid in structure and this appearance corresponds with that observed under the electron microscope. In contrast, after formalin fixation and processing through solvents, the horny layer has a basket-weave appearance with hollow keratinocytes, only tin peripheral keratinized cytoplasm remaining in the preparations. A thin transitional basal portion of the horny layer is composed of solid cells even after formalin fixation and this region appears to correspond to the basal part of the horny layer seen in electron micrographs. The differences produced by osmium and formalin fixation suggest that normally soluble degradation products of the horny cells together with absorbed sebum may be precipitated and rendered insoluble by osmium tetroxide but these substances arc dissolved out during histological processing after formalin fixation. In a further experiment, skin was fixed in formalin and taken through water and lipid solvents before immersing it in osmium tetroxide. Soluble reactive substances were removed in this way and only the insoluble keratinized peripheries of the horny cells remained to be stained with osmium giving a basket-weave appearance. The effects of different fixatives on the epidermis show that a correct appreciation of the horny layer can only be obtained by examining it by light microscopy and by electron microscopy. Hairs examined in keratin studies are normally first washed in various solvents to remove all soluble substances. Subsequent conclusions on the keratin structure are, therefore, more reliable for hair than for the epidermal horny layer in which the soluble substances are not removed. Some fibrils seen in electron micrographs of the horny layer are probably precipitated from soluble short-chain polypeptides normally found in the keratinocytes, and this confuses keratin studies on the epidermis. [ABSTRACT FROM AUTHOR]

Studies of the histochemical properties of non-specific esterase in the epidermal dendritic cells of the mouse have shown that the enzyme is an acetylesterase which will hydrolyse naphthyl but not naphthol esters. It is sulphydryl dependent, insensitive to 10-4 M eserine, and inhibited by fluoride and organophosphate. The distribution of esterase activity and tyrosinase activity in epidermal dendritic cells has been investigated in relation to epidermal patterning in the tail and a coincidence of mosaic demonstrated. These findings are discussed in the context of patterning mechanisms and a possible subordinate relationship between the patterns of dendritic cell activity and scale and interscale regions of keratinization considered. [ABSTRACT FROM AUTHOR]

Our purpose has been to draw attention to the existence of sudoriferous metaplasia in a number of superficial neoplasms of the skin. The neoplastic cells arise by an adnexal deviation of the rete cells ; the matrices which they form represent neoplastic primordia in which, under suitable conditions, differentiation into sweat glandular structures will occur. The structure of individual tumours is linked to the degree of adnexal deviation. Six structural variants can be recognized, two being benign and four malignant. In their histology many examples of benign hidroacanthoma simplex correspond with the intraepidermal basal cell epithelioma as classically described by Jadassohn, Among the tumours generally classed as seborrhoeic warts are a few which represent formes frustes of hidroacanthoma simplex. The cancers include examples of intraepidermal carcinoma and of Bowen's disease. Reasons are advanced for the prolonged in situ course of many of the latter. [ABSTRACT FROM AUTHOR]

Examines the morphology, methods of production and specifity of the L. E. cell, a polymorphonuclear leucocytes containing a round homogeneous body. Significance of the cells in the diagnosis and wider clinical concept of systemic lupus erythematosus; Correlation of the cells with the various type of lupus erythematosus; Demonstration of the L. E. serum factor in the protracted systemic type of the disease.

This article discusses an unsealed hanging-drop technique for the investigation of microsporum in hair. Researcher Plaut Later recorded with photomicrographs and other illustrations his attempts to grow ringworm fungi from hair and scales which he had collected from patients infected by these fungi. He placed the material moistened with a little water in the centre of a slide and over it a cover-slip which was supported at the corners by drops of wax on the slide. As the apparatus cooled, moisture condensed on the underside of the cover-slip. Infected material was then introduced into the film of moisture and the cover-slip was finally sealed to the glass cylinder, thus closing the cell.

Two attenuated strains of Shigella flexneri 2a, a Shigella-E. coli hybrid, and a streptomycin-dependent mutant, were safely given to adult male volunteers. When vaccinated individuals ingested virulent S. flexneri 2a, clinical disease and fecal excretion of virulent organisms occurred with less frequency than in unvaccinated volunteers. The level of immunity resembled that seen after recovery from active infection. These studies have given some indication that bacillary dysentery may be controlled by an oral live vaccine, and field trials designed to quantitate induced immunity are planned for the near future. [ABSTRACT FROM PUBLISHER]

The article focuses on some of the molecular mechanisms involved in the regulation of cell function and offers a conceptual framework on the categories of all potential molecular control mechanisms. It talks about the regulation of the general levels of cellular flow of information as a way to systematically deal with achieving cell regulation. The four basic levels at which control can be exerted include the transcription of genetic information from DNA to RNA, the translation of information from RNA to protein, direct modification of a protein's activity, and degradation of protein.

This year marks the three-hundredth anniversary of Robert Hooke's discovery of cells. A brief look at Hooke's life and work shows him to have been a scientist of genius and exciting versatility. Nevertheless, scientific history has been neglectful of his importance, and this anniversary provides a fine opportunity to become reacquainted with his brilliance. [ABSTRACT FROM AUTHOR]