These results suggest a poor relation between dry eye tests and symptoms, which represents a quandary in dry eye clinical research and practice.

Contact Lens Materials Given the fact that approximately 90% of the world's contact lens wearers are wearing soft lenses with no recent change in this figure, 1 this report primarily concerns itself with the role of soft lens materials and designs and care solutions in CLD, with some discussion of rigid gas permeable lens (RGP) materials or designs where appropriate. Conventional Hydrogel Materials The pioneering work of Wichterle and colleagues 2,3 is well known as a basis for the development of hydrogel polymers for soft contact lenses, including lightly cross-linked polymers of 2

Tear film thinning can be analyzed in terms of flow in three spatial directions: (1) outward (evaporation), (2) inward (into the epithelium or contact lens), and (3) parallel to the tear film surface. The results indicate that the second mechanism may be unimportant. Studies have shown a range of tear film evaporation rates from 0.24 to 1.45 microm/min, whereas, when the lipid layer is washed away from the tear film, the thinning rate, due to evaporation, would be approximately 7 microm/min. Thus, slow thinning rates may be due to tear film evaporation, whereas rapid rates (which are often greater than 7 microm/min) presumably include other mechanisms such as dewetting, Marangoni flow (i.e., surface tension gradients), and pressure-gradient flow.

A significant number of contact lens wearers are not satisfied with contact lenses and are at risk for discontinuation.

MG scores between lids were significantly different but correlated. MG loss was significantly correlated to tear film characteristics including lipid layer thickness and stability. MG thickness and bent angle of the UL were related to NIBUT. The combination of both lids' MG loss showed best predictive ability of dry eye.

No abstract

Meibomian gland dysfunction is one of the most common causes of dry eye resulting in morphology changes to the meibomian glands. Meibography provides an in vivo means to assess the structure of the meibomian gland. Over the past 40 years, meibography has undergone significant development regarding its application to research and clinical practice. This review describes the evolution of the various meibography techniques, grading methods, and their diagnostic relevance.

In the present report we describe a heretofore unrecognized role for a Jak/STAT signaling pathway, namely the stimulation of expression of the aromatase P450 (CYP19) gene, and hence of estrogen biosynthesis, in human adipose tissue. Expression of this gene in adipose tissue as well as in adipose stromal cells maintained in the presence of serum and glucocorticoids is regulated by a distal TATA-less promoter, I.4, which contains a glucocorticoid response element, an Sp1 binding site, and an interferon-gamma activation site (GAS) element. The stimulatory action of serum (in the presence of dexamethasone) can be replaced by interleukin (IL)-11, leukemia inhibitory factor, and oncostatin-M, as well as by IL-6, providing the IL-6 soluble receptor is also present. Stimulation of the cells by these factors led to rapid phosphorylation of Jak1, but not Jak2 or Jak3, on tyrosine residues. STAT3 but not STAT1 was also phosphorylated and bound to the GAS element in the I.4 promoter region. When regions of this promoter were fused upstream of the chloramphenicol acetyltransferase reporter gene and transfected into the cells, mutagenesis or deletion of the GAS element led to complete loss of reporter gene expression. Since adipose tissue is the major site of estrogen biosynthesis in men and in postmenopausal women, this pathway involving a Jak/STAT signaling mechanism acting together with glucocorticoids and Sp1 appears to be the principal means whereby estrogen biosynthesis is regulated in the elderly.