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Biomedical subjects

B Forslind

Publications and source records attributed to B Forslind.

At least 37 records · Page 2Linked to original sources
PubMed1993

Water and ion distribution profiles in human skin.

Bulk sample x-ray microanalysis (XRMA) of human gluteal skin was performed to provide data on water and ion profiles over the epidermal cross section. All samples were analyzed both in the frozen hydrated state and in the frozen dried state. This allows, for the first time, a quantitative determination of the local water content in different strata of the skin. A steep water gradient was found in the stratum corneum towards the stratum granulosum, while the water content was constant in all deeper layers of the skin, including the papillary dermis. Previously demonstrated distributions over the epidermis of the monovalent ions sodium (Na), potassium (K) and chlorine (Cl) given in concentrations per unit dry weight were confirmed, as were the distributions of phosphorus (P) and sulfur (S). Combining the water and ion distributions, our data indicate the major monovalent ions Na, K and Cl to be in equilibrium between the stratum corneum and the dermis if the assumption is that all monovalent ions are in solution and that all the water of the tissue is available as solvent for the ions. This result does not disprove the existence of an ion transport gradient in the epidermis but sets significant bounds to it.

Body Water↗
PubMed1992

Dimensions of capsular collagen fibrils: image analysis of rapid compared with slow tissue expansion for breast reconstruction.

Thirty women who were to undergo breast reconstruction by tissue expansion were randomly divided into two groups. Those in the first group were to undergo expansion once a day (rapid expansion) and the second group once a week (slow expansion). When the expanders were replaced by permanent prostheses, biopsy specimens were taken from the capsules around the expanders, and were examined by transmission electron microscopy at a magnification x 22,000. The diameters of the collagen fibrils in the capsules were analysed by an interactive image analysis system and measured. An analysis of variance was performed on a test series to optimize the sample. Ninety fibrils from each patient (two patients were excluded), were analysed and there were no significant differences in collagen fibrillar diameters (about 50 nm) between those who had undergone rapid or slow expansion, or between patients who had also undergone radiotherapy to the chest wall and those who had not. These results indicate that the collagen fibrils may still be in a transitional stage, and that further longer term studies are desirable. It is difficult, however, to see how they could be justified ethically in patients who are otherwise well.

Adult↗
PubMed1992

Elemental changes in guinea pig epidermis at repeated exposure to sodium lauryl sulfate.

Epidermal hyperplasia is the response of the epidermis to external harmful stimuli. The control and regulation of this hyperplasia is not completely understood. It has been proposed that changes in the cellular sodium/potassium ratio are of importance in the regulation of cell proliferation. To evaluate if such a change in the elemental content of epidermal cells can be one factor to consider at irritant contact dermatitis, we performed a quantitative assessment of sodium lauryl sulfate (SLS)-induced contact reactions in the guinea pig. SLS was applied 1, 2 or 3 times and biopsies were obtained at 24 and 84 h after the last application. It was found that repeated exposures to SLS induced a hyperplasia of epidermis at 24 h persisting at 84 h. At 24 h there were significant changes in the sodium and potassium content of the keratinocytes. At 84 h there was still an increased potassium level in the cells and the sodium/potassium ratio was significantly decreased in epidermis exposed three times to SLS. This implies that changes in cellular sodium/potassium ratios occur in epidermal hyperplasia following irritant stimuli.

Animals↗
PubMed1992

Quantitative and computer assisted electron microscopic and microprobe studies in dermatology.

Electron microscopes are not yet routine instruments in modern dermatological pathology even though they have provided detailed data about pathological changes in the skin for more than three decades. At present, dermatopathology is still dominated by light microscopy and especially so since the introduction of immunological techniques such as the use of monoclonal antibodies. These tools applied at electron microscopic resolution, however, may provide the ultimate identification of cells and subcellular components. In addition, electron microscopes have no peers in areas of quantitative investigation at subcellular levels, e.g. morphometry. The electron microprobe provides a unique tool in elemental analysis and may be used for the analysis of conventionally prepared specimens when foreign matter, not soluble in water, is deposited in the tissue. On the other hand, with water soluble substances the technique is most effective when freeze sections are utilized. This paper gives a selected review of the present day status of quantitative skin research as analysed with electron microscopy and the related technique of electron microprobe analysis.

Electron Probe Microanalysis↗
PubMed1991

Morphometric evaluation of collagen fibril dimensions in expanded human breast skin.

A great innovation in plastic surgery in recent years has been skin expansion, which has provided the discipline with new possibilities for skin reconstruction. At present, little is known about the biology of skin expansion although it is clear that cell proliferation occurs both in the epidermis and the dermis. During previous morphological investigations of skin under expansion we recorded a number of signs comparable with those seen in wound healing. In the present study, the collagen fibril diameter of of skin before and under expansion has been recorded using an IBAS computer-based morphometric system. Preferentially, we have studied the papillary dermis where the most conspicuous morphological events occur.

Adult↗
PubMed1991

Langerhans' cell histiocytosis in an adult.

A woman with typical skin lesions of histiocytosis X is reported. Electron microscopic and immunohistochemical investigations revealed a large number of markedly long Birbeck Langerhans' cell granulae. During treatment with Interferon alpha -2b, the patient developed infarctus cerebri and died.

Adult↗
PubMed1991

Hereditary hair changes revealed by analysis of single hair fibres by scanning electron microscopy.

In many disorders with a genetic background the sparsity of scalp hairs may deter the clinician from trying to extract information from single hair fibres. Presenting a number of diverse conditions, we propose to show that simple measures can be taken in the doctor's office which makes single fibre analysis a useful tool for assessment of factors involved in genetic disorders including the integument and its appendages. The paper is focussed on the utilization of the scanning electron microscope with the goal of demonstrating that pertinent information can be gained where information from transmission electron microscopy and other techniques are not immediately available.

Adolescent↗
PubMed1991

Proton induced X-ray emission analysis of biological specimens--past and future.

Proton induced X-ray emission (PIXE) analysis is a comparatively new member of the family of spectrographic methods. In the last decade PIXE techniques have been applied to biological problems with great success. This review gives a condensed presentation of recent developments in biological (medical, zoological, and botanical) applications of PIXE analysis with special focus on factors which commonly influence the results, such as calibration, contamination, and preparation. The great advantage of PIXE analysis in studying physiologically important trace elements such as Zn, Mg, Fe, and Cu is underlined. Elemental mapping not only allows quantitative elemental analysis, but can also demonstrate the important differences in the morphological distributions of elements by comparing normal and pathological tissue.

Animals↗
PubMed1989

The use of scanning electron microscopy in the analysis of pathological hairs.

The potentials of the scanning electron microscope (SEM) have only to a certain degree been exploited in the study of pathological hair fibers. In this review brief viewpoints on aspects of preparation and interpretation are discussed. It is shown that SEM will reveal important facts on the morphology of pathological hairs is appropriate experiment are performed, such as forming a knot on the fiber. Such a simple experiment will provide information on the fiber cross section, and on the tensile strength of the cuticle and the fiber. Complementary methods for qualitative and quantitative analysis of pathological hair fibers are suggested.

Hair↗
PubMed1989

Sodium lauryl sulfate enhances nickel penetration through guinea-pig skin. Studies with energy dispersive X-ray microanalysis.

The effect of sodium lauryl sulphate (SLS), a common ingredient of detergents, on the penetration of nickel through the stratum corneum in the guinea-pig skin model was studied with energy dispersive X-ray microanalysis (EDX) to evaluate the barrier-damaging properties of this common detergent. The EDX technique allows a simultaneous determination of physiologically important elements, e.g., Na, Mg, P, Cl, K, Ca and S in addition to Ni at each point of measurement in epidermal cell strata. Our results show that SLS reduces the barrier function to Ni-ion penetration of the stratum corneum. In addition we have shown that EDX allows analysis of the influence of different factors involved in nickel penetration through the skin by giving data on the physiological effects on the epidermal cells caused by the applied substances.

Animals↗
PubMed1988

Clinical applications of scanning electron microscopy and energy dispersive X-ray analysis in dermatology--an up-date.

Dermatological papers comprising scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis data published 1983 through 1986 in international journals are reviewed, as an update to our 1984 paper on Clinical applications of scanning electron microscopy and X-ray microanalysis in dermatology. The present paper not only deals with a review of recent publications in this area but also presents the application of microincineration to hair and cryosectioned freeze-dried skin specimens. Examples of the increased contrast obtained in hair cross sections are presented and a discussion on the feasibility of microincineration at analysis of hair and skin cross sections is given. Particle probe analysis (EDX: energy dispersive X-ray analysis and PMP: proton microprobe analysis) as applied to hair and skin samples are presented with stress put on the proton probe analysis. The complementarity of EDX and PMP is demonstrated and future applications are suggested.

Animals↗
PubMed1988

Human hair form. Morphology revealed by light and scanning electron microscopy and computer aided three-dimensional reconstruction.

The alleged relationship between the cross sectional shape of the hair shaft and the form of the hair, eg, curly or straight hair, has been challenged. By serial sections of human hair follicles from ten patients representing the three biological races, the relation between the follicle form and the hair form was studied. Using three-dimensional computer-aided reconstruction it was demonstrated that the follicle form determines the hair form, eg, the Negroid follicle has a helical form, whereas that of the Oriental follicle is completely straight. The caucasoid follicle represent variation between these extremes. However, even a straight caucasoid follicle may produce a hair shaft that has an oval cross section.

Adult↗
PubMed1987

Membrane-coating granules in "dry" non-eczematous skin of patients with atopic dermatitis. A quantitative electron microscopic study.

In recent years much interest has been focused on the functions of the membrane-coating granules (MCGs). These granules seem to play an essential role in the formation of the barrier of the stratum corneum by extruding their lipid-rich content into the extracellular space of the corneocytes. The dry non-eczematous skin in atopic dermatitis has been reported to have defective barrier function. In the present study a quantitative electron microscopic analysis was made of the volume of MCGs in the transition zone between the stratum granulosum and stratum corneum in dry skin of patients with atopic dermatitis. The relative volume of MCGs was significantly greater than that in normal skin. This finding may indicate a disturbance of the "maturation" of the MCGs, leading to a defect in the barrier function in atopic dermatitis.

Adult↗