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Biomedical subjects

J A Witkowski

Publications and source records attributed to J A Witkowski.

At least 91 records · Page 5Linked to original sources
PubMed1983

A cell surface abnormality in Duchenne muscular dystrophy: intercellular adhesiveness of skin fibroblasts from patients and carriers.

The intercellular adhesiveness of skin fibroblasts from patients and carriers of Duchenne muscular dystrophy (DMD) and control subjects has been determined using couette viscometers. The values for 12 DMD patients (mean = 1.38, SEM = 0.1, n = 32) were significantly lower than for ten control subjects (mean = 3.17, SEM = 0.2, n = 22). According to the Lyon hypothesis, carriers of DMD should be mosaics of cells expressing the normal and DMD phenotypes, and their cultured skin fibroblasts should have intercellular adhesiveness intermediate between that for normal and DMD cells. Cells from three obligate heterozygotes and five individuals at high risk of being carriers had normal values (in both groups mean = 2.82) in contrast to artificial 1:1 mixtures of normal and DMD cells that had intermediate values (mean = 2.22, SEM = 0.2, n = 15). This unexpected finding is probably the result of "correction" of the DMD cells by normal gene product from the cells expressing the normal gene.

Cell Adhesion↗
PubMed1983

Freeze-fracture analysis of plasma membranes in Duchenne muscular dystrophy. A study using cultured skin fibroblasts.

Quantitative freeze-fracture studies of the numercial density and distribution of intramembrane particles (IMP) were carried out on the plasma membrane of cultured skin fibroblasts from 4 patients with Duchenne muscular dystrophy and 3 normal controls. Analysis of P and E fracture faces of the fibroblast plasma membrane failed to show any significant differences in either IMP density or distribution between normal and dystrophic specimens. In contrast to previous reports, our results indicate that an altered IMP density is not a characteristic feature of the dystrophic cell membrane.

Cell Adhesion↗
PubMed1982

Histopathology of the decubitus ulcer.

The histologic studies of the decubitus ulcer spectrum, which include blanchable erythema, nonblanchable erythema, decubitus dermatitis, decubitus ulcer, and the black eschar/gangrene reveal a dynamic process. The initial change occurs in the vessels of the papillary dermis. This is followed by necrosis of skin structures. The eschar/gangrene represents a full-thickness defect due either to prolonged ischemia and anoxemia or a sudden large vessel occlusion caused by shearing injury.

Adult↗
PubMed1982

Bacterial skin infections: management of common streptococcal and stapylococcal lesions.

Skin infection occurs in any age-group, sex, and race but is particularly common in children. It is usually minor, but may indicate underlying systemic disease or may lead to systemic infection. Streptococci and staphylococci are common causes. Group A beta-hemolytic streptococci account for the majority of streptococcal infections in man. Infection most often involves the lower extremities and produces spreading erythema and necrosis but little purulence. Staphylococcal infections most commonly involve the face, the hair follicles and eccrine sweat ducts being the initial sites. Lesions appear as bullae and pustules with a narrow rim of erythema. Intense cellulitis surrounding the lesions usually points to a virulent, penicillin-resistant strain of Staphylococcus. Treatment of both types of infection consists of cleansing with antibacterial agents, removal of crusts, application of warm compresses, and use of topical or systemic antibiotics, depending on the severity of the infection and the type of pyoderma involved.

Bacterial Infections↗
PubMed1982

Porokeratosis of Mibelli. A perforating disease of the epidermis.

A case of linear porokeratosis of Mibelli is presented. Although there was no suggestion clinically of a perforating disorder, histologic examination revealed a cornoid lamella penetrating into the dermis. Special stains did not show any evidence of a transepidermal elimination syndrome.

Female↗
PubMed1981

Analysis of skin fibroblast aggregation in Duchenne muscular dystrophy.

Skin fibroblasts from patients with Duchenne muscular dystrophy have a low intercellular adhesiveness compared with normal cells when aggregated in a Couette viscometer (collision efficiencies of 2.52 and 4.62, respectively). The pattern of aggregation was quantitated using a digitizer system to measure the areas of particles (single cells and aggregates) formed after 20 min aggregation. This size analysis showed that the majority of dystrophic cells remained unaggregated but that a small number of very large aggregates was always formed. Normal cell suspensions only rarely contained large aggregates but contained many intermediate-size aggregates. These differences in intercellular adhesiveness and aggregate pattern formation indicate that there may be an alteration in the surface of dystrophic cells.

Cell Adhesion↗