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G W Elgart

Publications and source records attributed to G W Elgart.

25 records · Page 2Linked to original sources
PubMed1992

Comparative structural analysis of desmoplakin, bullous pemphigoid antigen and plectin: members of a new gene family involved in organization of intermediate filaments.

Desmoplakins (DP) and bullous pemphigoid antigen (BPA) are major plaque components of the desmosome and hemidesmosome, respectively. These cell adhesion structures are both associated intimately with the intermediate filament (IF) network. Structural analyses of DP and BPA sequences have indicated that these molecules are likely to form extended dumbbell-shaped dimers with a central rod and globular end domains. Recent sequence data have indicated that the N-terminal domains of both DP and BPA (like their C-terminal domains) are highly related: the former contain regions of heptad repeats that are predicted to form several alpha-helical bundles. Comparisons of DP and BPA protein sequences with that of plectin (PL), a 466 kDa IF-associated protein, have also revealed large scale homology. Identities between their N-terminal domains are: DP:BPA = 35%, DP:PL = 32%, BPA:PL = 40%, suggesting that BPA is more closely related to PL than DP in this region. In the C-terminal domains, which contain a 38-residue repeating motif, however, DP and PL are closer relatives (identities: DP:BPA = 38%, BPA:PL = 40%, DP:PL = 49%). The central domains of all three proteins have extensive heptad repeat substructure, express the same periodic distribution of charged residues, and are predicted to form two-stranded alpha-helical coiled-coil ropes. These observations suggest that DP, BPA and PL belong to a new gene family encoding proteins involved in IF organization.

Amino Acid Sequence↗
PubMed1991

Cutaneous metastasis from papillary carcinoma of the thyroid gland.

Cutaneous metastases from carcinoma of the thyroid gland are rare. We present the clinical, histologic, and immunohistochemical features of a solitary metastasis from papillary carcinoma of the thyroid. Our results indicate that this tumor can produce epithelial mucin and, therefore, must be differentiated from other metastatic carcinomas and from primary apocrine tumors of the skin. Positive staining for thyroglobulin confirmed the diagnosis in this case.

Carcinoma, Papillary↗
PubMed1991

Southern analysis of the 230-kD bullous pemphigoid antigen gene in normal humans, animals, and patients with junctional epidermolysis bullosa.

To begin to characterize the 230-kD bullous pemphigoid antigen (BPA) gene, we performed Southern analysis on genomic DNA with probes derived from 7 kb of cDNA that spans most of the coding region of this hemidesmosomal plaque protein. When hybridized to a 1-kb fragment of this BPA cDNA, normal human genomic DNA digested with EcoRI, BamHI, PstI, HindIII, or EcoRV showed only a single band, which was unique for each enzyme, indicating a single human gene for BPA. To determine if a related gene exists in animals, we used probes covering the full 7 kb of cDNA for Southern analysis of genomic DNA from various vertebrates. A related gene was detected in other mammals (monkey, cow, dog, rabbit, mouse, and rat) but not in chicken, frog, or fish. Under these same hybridization conditions a probe for human beta-actin could detect an actin gene in all these species. Furthermore, immunofluorescence showed that an antibody raised against portions of the 230-kD BPA bound to the epidermal basement membrane of mammals but not that of a bird or amphibian. Finally, because most patients with junctional epidermolysis bullosa (JEB) have defective hemidesmosomes in ultrastructure, and probably function, we analyzed genomic DNA from these patients. No restriction fragment length polymorphisms (RFLP) were detected when the DNA from 11 normals and 8 JEB patients (representing 16 possible defective genes) was digested with BamHI, EcoRI, or PstI and hybridized to any part of the cDNA. These findings indicate that 1) there is a single BPA gene in humans; 2) a closely related gene exists in other mammals but not birds, amphibia, or fish; and 3) gross abnormalities of the BPA gene are not characteristic of JEB patients.

Animals↗
PubMed1990

Congenital midline hamartoma: case report with histochemical and immunohistochemical findings.

We report the case of a polypoid nodule on the chin of an infant. Microscopically, the lesion featured numerous pilosebaceous units, eccrine sweat glands, arrectores pilorum muscles, mature adipose tissue, and prominent admixtures of skeletal muscle. This lesion has much in common with the accessory tragus, and is similar to the one reported earlier as rhabdomyomatous mesenchymal hamartoma. We feel the more general term congenital midline hamartoma is preferable, as it encompasses both the clinical and microscopic features of the lesion.

Chin↗
PubMed1990

Ant, bee, and wasp stings.

Stinging insect envenomation and allergy remain important clinical and research problems. Approximately 40 deaths occur annually as a result of these stings. The dermatologist can help to avoid this outcome by appropriate recognition of the offending insect and by instituting or arranging the appropriate therapy and avoidance. Bee-sting kits should be encouraged for sensitive individuals. Dermatologists should be alert to the increasing imported fire ant problem, be able to make the diagnosis, and help the patient recognize and avoid these pesky arthropods.

Adult↗