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J Rowsey

Publications and source records attributed to J Rowsey.

4 recordsLinked to original sources
PubMed2000

Measurement of mRNAs for TGFss and extracellular matrix proteins in corneas of rats after PRK.

PURPOSE: To assess the role of the transforming growth factor (TGF)ss system in formation of corneal haze after excimer laser photorefractive keratectomy (PRK), levels of mRNAs for three TGFss isoforms (TGFss1, TGFss2, and TGFss3), the TGFss type II receptor (TssRII), and extracellular matrix (ECM) genes including fibronectin (FN), collagen I, collagen III, and collagen IV were measured in rat corneas. METHODS: Corneas were graded for corneal haze at 0, 1.5, 7, 21, 42, and 91 days after PRK. Total RNA was isolated from pooled corneas, and the levels of mRNAs were measured using competition-based quantitative reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Severe corneal haze developed by day 42 and persisted to day 91. Levels of TGFss1 mRNA were high in rat corneas before PRK and remained relatively constant. In contrast, levels of TGFss2 and TGFss3 mRNAs were very low in normal corneas, increased 300-fold and 25-fold, respectively, on day 21, and remained elevated on day 91. Levels of mRNA for TssRII increased, with a peak elevation of 50-fold on day 42 after PRK. Levels of mRNAs for ECM proteins also increased. Fibronectin mRNA was nondetectable in normal corneas but rapidly increased to 675 copies/cell on day 7 and remained elevated to day 91. Collagen III mRNA levels peaked on day 21 with a 700-fold increase compared with a very low level of expression in normal cornea, and then decreased on day 91. Expression of collagen I mRNA lagged expression of collagen III mRNA and peaked at day 42 after PRK with a 1200-fold increase over normal cornea. In contrast, mRNA for collagen alpha(1)IV, a major component in basement membranes, remained relatively stable through day 21 and then increased slightly on days 42 and 91. CONCLUSIONS: The synchronized increase in mRNA synthesis for both the TGFss system and key ECM genes supports the hypothesis that TGFss is a key growth factor promoting stromal haze formation in corneas after PRK and suggests that limiting TGFss system may reduce corneal scarring after excimer laser ablation.

Animals↗
PubMed1993

Coagulase-negative staphylococci in conjunctivitis and blepharitis.

Coagulase-negative staphylococcus (C-NS) are regarded as normal flora of the lids and conjunctiva. The ability of these organisms to cause conjunctivitis and blepharitis can be overlooked or disregarded. To elucidate the role of individual C-NS species in these eye diseases we compared Staphylococcus sp. isolated from the conjunctiva and lids of 50 healthy volunteers with 248 strains of Staphylococcus isolated from patients with staphylococcal conjunctivitis or blepharitis. S. epidermidis was the most frequent species isolated from the conjunctiva and lids of both groups. S. aureus was isolated only from infected patients. No individual C-NS species was found to be significantly associated with eye disease, but the colony count of C-NS after isolation was a useful indicator of conjunctivitis and blepharitis. The ability of Staphylococcus to ferment mannitol or mannose was associated with isolates only from infected patients.

Blepharitis↗
PubMed1988

[A trial use of lenses of human placental collagen in epikeratoplasty procedures].

Epikeratoplasty is a refractive surgery procedure described by Werblin and Kaufman which is simple, effective and reversible. However its development is hampered by the need of human corneas. We evaluated this procedure in rabbits and monkeys using lenticules of human collagen. The collagen is obtained from frozen human placentas, washed and subjected to pepsin digestion; it is contained in the supernatant of centrifugation and can be isolated by a physico-chemical treatment. 15 days after surgery the lenses of 14 rabbits were completely covered with a layer of epithelial cells. 6 months after surgery, the eyes of 14 monkeys were quiet and the lenses were covered with an epithelium made up of 2 to 5 layers of cells. The lens exhibited no inflammatory infiltration and there was no inflammatory reaction around the lens. These studies are still preliminary and longer term tests are necessary. These initial results are very encouraging, prompting us to develop the use of this type of material in refractive surgery.

Animals↗