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J Arnn

Publications and source records attributed to J Arnn.

5 recordsLinked to original sources

Common structural domains in the sarcoplasmic reticulum Ca-ATPase and the transverse tubule Mg-ATPase.

Transverse tubule (TT) membranes isolated from chicken skeletal muscle possess a very active magnesium-stimulated ATPase (Mg-ATPase) activity. The Mg-ATPase has been tentatively identified as a 102-kD concanavalin A (Con A)-binding glycoprotein comprising 80% of the integral membrane protein (Okamoto, V.R., 1985, Arch. Biochem. Biophys., 237:43-54). To firmly identify the Mg-ATPase as the 102-kD TT component and to characterize the structural relationship between this protein and the closely related sarcoplasmic reticulum (SR) Ca-ATPase, polyclonal antibodies were raised against the purified SR Ca-ATPase and the TT 102-kD glycoprotein, and the immunological relationship between the two ATPases was studied by means of Western immunoblots and enzyme-linked immunosorbent assays (ELISA). Anti-chicken and anti-rabbit SR Ca-ATPase antibodies were not able to distinguish between the TT 102-kD glycoprotein and the SR Ca-ATPase. The SR Ca-ATPase and the putative 102-kD TT Mg-ATPase also possess common structural elements, as indicated by amino acid compositional and peptide mapping analyses. The two 102-kD proteins exhibit similar amino acid compositions, especially with regard to the population of charged amino acid residues. Furthermore, one-dimensional peptide maps of the two proteins, and immunoblots thereof, show striking similarities indicating that the two proteins share many common epitopes and peptide domains. Polyclonal antibodies raised against the purified TT 102-kD glycoprotein were localized by indirect immunofluorescence exclusively in the TT-rich I bands of the muscle cell. The antibodies substantially inhibit the Mg-ATPase activity of isolated TT vesicles, and Con A pretreatment could prevent antibody inhibition of TT Mg-ATPase activity. Further, the binding of antibodies to intact TT vesicles could be reduced by prior treatment with Con A. We conclude that the TT 102-kD glycoprotein is the TT Mg-ATPase and that a high degree of structural homology exists between this protein and the SR Ca-ATPase.

Animals↗

Individualizing patient care.

Patients are people as well as potential problems. Increasing our awareness of patients' lifestyle preferences, as well as developing more productive ways to interact with them, can promote growth along with recovery. The very least it can do is to facilitate working with patients and reduce the negative impact of stress of conflict in a very demanding profession.

Female↗

Human autoantibodies against desmosomes: possible causative factors in pemphigus.

Pemphigus is a human disease that causes extensive blistering of the skin. This blistering is related to a loss of epidermal cell cohesion and is accompanied by circulating autoantibodies that stain epidermal cell surfaces, as shown by immunofluorescence microscopy. One of the major components involved in epidermal cell cohesion is the desmosome. The pathological changes that accompany pemphigus led us to determine whether the autoantibodies are specific for desmosomes. Incubation of cultured mouse keratinocytes in medium containing pemphigus antiserum leads to cell separation at cell-cell contact sites, which possess desmosomes. Tissue sections of mouse skin processed for indirect immunofluorescence, using pemphigus antiserum or a rabbit antiserum directed against components of desmosomes, show similar punctate cell-surface staining patterns within the epidermis. Cultured mouse keratinocytes possessing well-defined intermediate filament bundles (tonofilaments) and desmosomes were processed for double indirect immunofluorescence, using a monoclonal antibody directed against mouse skin keratin and either pemphigus antiserum or the desmosome antiserum. The keratinocytes exhibit a complex system of keratin-containing tonofilaments. Tonofilaments in contacting cells are separated by thin dark bands at the cell surface, which correspond precisely to desmosomal plaques seen by phase-contrast microscopy. These bands specifically stain with both pemphigus antiserum and the desmosome antiserum. Double indirect immunofluorescence of the cultured mouse keratinocytes, using pemphigus antiserum and the desmosome antiserum, reveals that the pemphigus autoantibodies stain the same areas of cell-cell contact as the desmosome antibodies. Our evidence supports the idea that pemphigus blisters form, at least in part, from a specific antibody-induced disruption of desmosomes in the epidermis.

Animals↗

Orientation on understanding interpersonal influence.

Everyone influences and is influenced by others. Are you satisfied with the impact your influence has on others? If not, it can be changed by examining and working on the dimensions of your "style of influence," such as activity, visibility, involvement, and productivity. The author analyzes some of the opposites on a spectrum or "wheel of influence," showing how they may be melded by moderation to achieve the kind of impact you may wish. For instance, there is the analyzer vs. the performer, the leader vs. the follower, the experimenter vs. the organizer, and the asserter vs. the listener. As modes of influence, extremes in any dimension are self-defeating, but by balancing aspects of both sides, desirable "compromises" can be developed. Should you wish to change your style of influence, helfpful procedures to follow are suggested, which, hopefully, will result in satisfying interpersonal relationships and understanding.

Child↗