A previously healthy 70-year-old woman was hospitalized for acute pain and edema of her right leg. Deep vein thrombosis was suspected, and she was put on anticoagulant therapy. Ten hours later, she developed a massive swelling of the leg with a well-demarcated violaceous discoloration of the skin and hemorrhagic bullae.
View Article and Find Full Text PDFIn the embryo, epithelia give rise to mesenchyme at specific times and places. Recently, it has been reported (Greenburg, G., and E.
View Article and Find Full Text PDFThe disappearance of palatal medial edge epithelium (MEE) after fusion of secondary palatal shelves is often cited as a classical example of embryonic remodeling by programmed cell death. We reinvestigated this phenomenon in 16-day rat embryos, using light and electron microscopy. We confirm reports that the periderm of the two-layered MEE begins to slough after shelves assume horizontal positions.
View Article and Find Full Text PDFCell Motil Cytoskeleton
April 1990
Cell Motil Cytoskeleton
April 1990
We present a model of cell motility based on emigration of neural crest cells into the neural tube lumen under in vitro conditions (10% fetal calf serum or YIGSR) that inhibit their normal emigration from the base of the neuroepithelium into surrounding extracellular matrix (ECM). Ultrastructural observations reveal that cells lining the lumen are joined by zonulae adherentes (ZA), which are points of strong intercellular attachment, and thereby serve as markers for fixed regions of plasmalemma and cortical actin. Three major observations of the relationship of cells to the ZA support the "fixed cortex" model of mesenchymal cell migration.
View Article and Find Full Text PDFIn a prospective study, 41 patients with documented chronic macular edema of various causes were entered into a therapeutic trial of acetazolamide sodium, a carbonic anhydrase inhibitor. Each patient received a five-cycle cross-over regimen of treatment/no treatment with a further two cycles of cross-over with another diuretic, cyclopenthiazide, which does not inhibit carbonic anhydrase. At each cross-over patients were examined for evidence of macular edema.
View Article and Find Full Text PDFIn considering the mechanism of transformation of epithelium to mesenchyme in the embryo, it is generally assumed that the ability to give rise to fibroblast-like cells is lost as epithelia mature. We reported previously that a definitive embryonic epithelium, that of the anterior lens, gives rise to freely migrating mesenchyme-like cells when suspended in type I collagen matrices. Here, we show that a highly differentiated epithelium that expresses cytokeratin changes to a vimentin cytoskeleton and loses thyroglobulin during epithelial-mesenchymal transformation induced by suspension in collagen gel.
View Article and Find Full Text PDFThe trunk neural crest originates by transformation of dorsal neuroepithelial cells into mesenchymal cells that migrate into embryonic interstices. Fibronectin (FN) is thought to be essential for the process, although other extracellular matrix (ECM) molecules are potentially important. We have examined the ability of three dimensional (3D) ECM to promote crest formation in vitro.
View Article and Find Full Text PDFThe senior author has performed the Swanson implant arthroplasty for arthritis of the basal joint of the thumb for the past 12 years. Fifty-two patients with a total of 64 arthroplasties of the thumb were reviewed, with follow-up periods of 12-156 months (average, 4.4 years).
View Article and Find Full Text PDFBetween the third and sixth day of embryonic development, the avian corneal epithelium produces both a basal lamina and the primary corneal stroma composed of 20 orthogonally arranged layers of collagen fibrils. If the epithelium is removed by enzyme treatment from the basal lamina and stroma, the basal cell surface extends cell processes (blebs) which contain disorganized actin filaments and the epithelium decreases production of collagen. When placed on extracellular matrix or on Millipore filters in media containing soluble matrix molecules, the epithelium retracts the blebs, forms an organized basal actin cortical mat, and doubles its production of collagen.
View Article and Find Full Text PDFOsteoarthritis should initially be treated conservatively with the use of oral medication, intra-articular steroid injections, hand therapy, and splinting. The reduction of pain and the resultant increase in function to the patient are the ultimate goals of this treatment.
View Article and Find Full Text PDFThe case of a 73-year-old man who developed acute thrombosis of the left subclavian artery during CPR is presented. The patient was known to have severe chronic obstructive lung disease, hypertension, coronary artery disease, and severe peripheral vascular disease. He was admitted with ventricular fibrillation.
View Article and Find Full Text PDFOphthalmology
December 1986
A retrospective review of 13 cases of lymphangioma has led to a classification of these lesions into categories of superficial, deep, and combined types. The clinical manifestations, prognosis, and management directly correlate with the pathophysiology and the location of the lesions. Superficial lesions consist of isolated multicystic vascular abnormalities of cosmetic significance only.
View Article and Find Full Text PDFA number of adult and embryonic epithelia, when suspended within native type I collagen gels, give rise to elongate bipolar cells that migrate freely within the three-dimensional matrix. The morphology of these newly formed mesenchyme-like cells is indistinguishable from "true" mesenchymal cells at the light and ultrastructural level. In this report, we extend previous observations on the transformation of embryonic avian lens epithelium to mesenchyme-like cells.
View Article and Find Full Text PDFSporothrix schenckii is a fungus known to cause infection of skin in the subcutaneous tissues. In this case tenosynovitis was caused by sporotrichosis resulting in rupture of the extensor tendon. Excision of the involved tenosynovium and repair of the tendons were done.
View Article and Find Full Text PDFPreviously, we have shown that embryonic corneal epithelia can interact with, and respond to, soluble extracellular matrices (ECM) (laminin, collagen, and fibronectin). The basal surface of epithelia isolated free of the underlying ECM can be seen to be disrupted by numerous blebs that sprout from this formerly smooth surface. Laminin, collagen, or fibronectin added to the culture medium cause the epithelium to reorganize its cytoskeleton and flatten its basal surface.
View Article and Find Full Text PDFAnterior dislocation of the proximal interphalangeal joint is a complex injury involving specific pathomechanics. Progression of this injury to a chronic stage is associated with considerable morbidity in the form of pain, instability, and loss of motion in the involved joint. Surgical reconstruction is complicated and results of delayed intervention are compromised.
View Article and Find Full Text PDFA patient with nonunion of the capitate presented for treatment with a painful, snapping wrist. Grafting was successful in obtaining union of the fracture and relief of symptoms.
View Article and Find Full Text PDFThe embryonic avian corneal epithelium in vitro responds to extracellular matrix (ECM) molecules in either soluble or polymerized form by flattening its basal surface, organizing the basal cortical actin cytoskeleton, and stepping up its production of corneal stroma twofold. Embryonic corneal epithelia, like hepatocytes and mammary gland cells, seem to contain heparan sulfate proteoglycan (HSPG) in their plasmalemma, which may interact with actin on the one hand or underlying collagen on the other. Work on the corneal epithelium suggests that, in addition to HSPG, specific glycoprotein receptors for laminin and collagen exist in the basal plasmalemma and play the critical role in actually organizing the basal epithelial cytoskeleton.
View Article and Find Full Text PDFArch Environ Health
March 1985
Hematological findings on a population of 70 male workers exposed to benzene revealed no significant differences when compared statistically to a control group on the basis of estimated cumulative doses using analysis of variance (ANOVA) and Dunnett's t statistic procedure. The hematological data evaluated included the following parameters: red blood cell counts, white blood cell counts, and hemoglobin levels. Cumulative benzene exposure indices for each employee were estimated utilizing available personal monitoring and general air sampling data, as well as the professional judgment of local environmental health engineers familiar with the operations.
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