Alveolar surfactant protein A (SP-A) is endocytosed by type II epithelial cells through clathrin-dependent uptake and targeted to lamellar bodies for resecretion. However, the mechanism for secretion of newly synthesized SP-A, whether regulated exocytosis of lamellar bodies or constitutive secretion, is unresolved. If it is the latter, lamellar body SP-A would represent endocytosed protein. Ama...

PURPOSE To report six cases of late onset diffuse lamellar keratitis associated with epithelial defects 2 to 12 months following uncomplicated laser in situ keratomileusis (LASIK). METHODS Retrospective case series. RESULTS The interface inflammation and epithelial defects were treated aggressively with topical corticosteroids and topical antibiotics with complete resolution over 1 to 2 wee...

Lipid rafts are cholesterol and sphingolipid-enriched plasma membrane domains, Caveolae represent a subclass of lipid rafts and the chief structural proteins are caveolins (caveolin-1, -2 and –3). Caveolae formation plays a major role in epidermal barrier permeability, regulating lamellar body secretion and terminal differentiation. Disruption of the epidermal barrier leads to protease-activate...

We recently identified mutations of the keratinocyte transglutaminase gene as a cause of lamellar ichthyosis. In this study we analyzed two sporadic cases of lamellar ichthyosis. Transglutaminase activity measured in membrane extracts from cultured differentiating keratinocytes was within the range observed in normal individuals. Western blot and Northern blot analysis revealed normal size and ...

PURPOSE To compare the measurement of contrast sensitivity at a distance in patients submitted to penetrating keratoplasty versus patients submitted to deep anterior lamellar keratoplasty for keratoconus treatment. METHODS Contrast sensitivity of fourteen subjects submitted to penetrating keratoplasty and fourteen subjects submitted to deep anterior lamellar keratoplasty have been analyzed th...

Dendritic lamellar bodies have been reported to be associated with dendrodendritic gap junctions. In the present study we investigated this association at both the morphological and electrophysiological level in the olivocerebellar system. Because cerebellar GABAergic terminals are apposed to olivary dendrites coupled by gap junctions, and because lesions of cerebellar nuclei influence the coup...

The phase behavior of mixed lipid dispersions representing the inner leaflet of the cell membrane has been characterized by X-ray diffraction. Aqueous dispersions of phosphatidylethanolamine:phosphatidylserine (4:1 mole/mole) have a heterogeneous structure comprising an inverted hexagonal phase H(II) and a lamellar phase. Both phases coexist in the temperature range 20-45 degrees C. The fluid-t...

Patients with atopic dermatitis (AD) have an epidermal barrier dysfunction, which allows invasion of allergens to occur. Stratum corneum skin barrier is formed by corneocytes and extracellular lipids extruded from the epidermal lamellar bodies. In a controlled, randomized, double-blinded, right-left comparison study we investigated the effect of pimecrolimus (PIM) cream compared with triamcinol...

We used the technique of lineal analysis to study the influence of 48 h of hyperoxia on cytoplasmic organelles of pulmonary granular pneumocytes with particular reference to their lamellar bodies. We undertook this study because lamellar bodies are considered to be storage granules for pulmonary surfactant and because we had found that hyperoxia decreased [(14)C]leucine incorporation into prote...

The effects of the slow Ca++ channel blocker, nifedipine, and ACAT inhibitor, octimibate, on cholesterol-loaded macrophages were compared at the ultrastructural level. The Ca++ antagonist induced the formation of membrane-surrounded "lamellar bodies" originating from lysosomes. The macrophages secreted these lamellar bodies, which were rich in phospholipids and cholesterol, into the culture med...