Masataka Kawai

Ocular surface and tear functions after topical cyclosporine treatment in dry eye patients with chronic graft-versus-host disease

We investigated the effect of 0.05% topical cyclosporine (Cys) on the ocular surface and tear functions in dry eye patients with chronic GVHD (cGVHD) in a prospective comparative study. Thirty eyes of 15 patients refractory to baseline treatment were recruited and the patients assigned for topical Cys treatment group (14 eyes of 7 patients) and control group (12 eyes of 6 patients) respectively. Two patients dropped out because of intolerable irritation while using topical Cys eye drops. Visual analog scale symptom scores, corneal sensitivity, Schirmer I test value, tear film break-up time (TBUT), tear evaporation rate and ocular surface vital staining scores were recorded at baseline and at the end of the following one month. Conjunctival impression and brush cytology were performed before and after the treatment. After topical Cys treatment, significant improvements were found in symptom scores, corneal sensitivity, tear evaporation rate, TBUT, vital staining scores, goblet cells density, conjunctival squamous metaplasia grade, inflammatory cell numbers and the MUC5AC expression. Our study suggests that 0.05% topical Cys may be an effective treatment for dry eye patients with cGVHD. The improvements in the ocular surface and tear functions resulted presumably from the decreased inflammation, increased goblet cell density and MUC5AC mRNA expression.

Decreased substance P concentrations in tears from patients with corneal hypesthesia.

PURPOSE To determine whether substance P concentrations in tears reflect corneal hypesthesia. METHODS Sixteen patients with unilateral corneal hypesthesia participated in this study. Unstimulated tears were collected from each eye of all subjects. Substance P concentrations in tears were measured by an enzyme immunoassay system. RESULTS Substance P concentrations in tears from the affected eye were lower than those in tears from the unaffected eye in all subjects. The mean concentration of substance P in tears from affected eyes was 197.7 +/- 69.5 pg/mL, markedly lower than those from unaffected eyes (333.2 +/- 74.6 pg/mL). CONCLUSION Substance P concentrations in tears, which are thought to reflect the neuropeptides levels in ocular tissues, can be used as an indicator of corneal denervation.

Aqueous humor levels of topically applied levofloxacin in human eyes

Purpose. To evaluate transcorneal penetration of topically applied 0.5% levofloxacin into the aqueous humor in human eyes. Methods. Twenty cataract patients (14 females, 6 males) received 3 drops of 0.5% levofloxacin at 15 min intervals from 90 minutes before the surgery. At the beginning of the cataract surgery, 50 µL of aqueous humor was aspirated from the anterior chamber and stored at -80°C until analysis. The drug concentration of the samples was analyzed using high-performance liquid chromatography. Results. A mean aqueous humor level of levofloxacin was 1.00 ± 0.48 µg/mL (mean ± standard deviation, n = 20), ranging from 0.30 µg/mL to 2.32 µg/mL. Conclusions. The mean concentration of levofloxacin in the aqueous humor was higher than the MIC 90 values against some common pathogens of postoperative endophthalmitis, although a great degree of interpatient variability was present.

A CD40-CD154 Interaction in Tissue Fibrosis

OBJECTIVE To examine the role of an interaction between fibroblasts and mononuclear infiltrates through CD40-CD154 engagement in the development of tissue fibrosis. METHODS Cultured dermal fibroblasts derived from healthy skin were induced to express CD40 by adenoviral gene transfer, stimulated with soluble CD154, and evaluated for proliferation, gene expression, and protein expression in vitro. The skin of mice with bleomycin-induced skin sclerosis, a model for systemic sclerosis (SSc), was assessed for CD40 and CD154 expression, in vivo fibroblast proliferation, and the expression of specific genes. The effects of an anti-CD154 monoclonal antibody on bleomycin-induced skin sclerosis were also examined. RESULTS Upon stimulation with soluble CD154, cultured fibroblasts induced to express CD40 by adenoviral gene transfer proliferated and showed up-regulation of the genes for intercellular adhesion molecule 1, interleukin-6 (IL-6), IL-8, monocyte chemoattractant protein 1 (MCP-1), and RANTES, as well as up-regulation of their proteins. In the skin from bleomycin-treated mice, dermal fibroblasts expressed CD40, and mast cells and CD4+ T cells expressed CD154. Electron microscopic analysis revealed fibroblasts attached to mast cells and T cells with primitive contacts. The proliferation of fibroblasts and the up-regulated MCP-1 gene expression preceded thickening of the dermis. Finally, the anti-CD154 antibody inhibited the bleomycin-induced skin sclerosis by suppressing fibroblast proliferation and down-regulating MCP-1 expression. CONCLUSION The interaction between fibroblasts and mast cells or T cells through CD40-CD154 signaling is critical for fibroblast activation early in the course of fibrosis. Blockade of the CD40-CD154 signal may be a novel therapeutic strategy for human fibrotic diseases, such as SSc.

Substance P in human tears.

Purpose To determine the levels and biochemical characteristics of substance P–like immunoreactivity (SPLI) in human tears and ascertain whether substance P (SP) concentrations in tears reflect the condition of the ocular surface. Methods Unstimulated tears were collected with a micropipette. Tear samples were partially purified using C-18 cartridges. Levels of SPLI in purified samples were measured using an enzyme immunoassay (EIA). For biochemical characterization of SPLI, tear extracts were fractionated using high-performance liquid chromatography (HPLC); each fraction was then subjected to EIA. To determine the catabolism of SP in tears, synthetic SP was incubated in medium containing pooled tears and then analyzed using HPLC. Results The concentration of SPLI in normal human tears was 306.0 ± 96.5 pg/mL (mean ± SD, range 148–555 pg/mL). Levels of SPLI did not vary significantly by age or gender. Concentrations of SPLI in tears from eyes with unilateral corneal hypesthesia were lower than those in tears from contralateral healthy eyes. Diclofenac sodium eye drops reduced concentrations of prostaglandin E2 and SPLI in tears. Analysis using HPLC indicated that five different substances contributed to SPLI in tears and that SP was broken down into several fragments, including SP8–11, by enzymes present in tears. Conclusions Substance P is a normal component of human tears. Levels of SPLI in tears might reflect the denervated status of the ocular surface. Substance P is catabolized by degradative enzymes in tears to maintain the ocular surface by exerting the trophic effects of SP while avoiding undesirable effects.

Aqueous humor levels of topically applied levofloxacin, norfloxacin, and lomefloxacin in the same human eyes

Purpose: To assess the relative penetration of topical eyedrops of 3 fluoroquinolones into the aqueous humor in human eyes. Setting: Department of Ophthalmology, Sano‐Kosei Hospital, Sano, Japan. Methods: Fifty‐nine cataract patients (36 women, 23 men) received 3 drops each of levofloxacin 0.5%, norfloxacin 0.3%, and lomefloxacin 0.3% in the same eye at 15‐minute intervals beginning 90 minutes before cataract surgery. At the beginning of surgery, 50 &mgr;L of aqueous humor was aspirated from the anterior chamber and stored at −80°C until analyzed. The drug concentrations in the samples were analyzed using high‐performance liquid chromatography. Results: Five patients were excluded from the study because their sample volumes were insufficient. Norfloxacin was detected in 3 patients; the mean aqueous humor level was 0.10 &mgr;g/mL ± 0.02 (SD). Levofloxacin was detected in all cases; the mean aqueous humor level was 0.60 ± 0.28 &mgr;g/mL (n = 54). Lomefloxacin was not detected in 10 patients; the mean aqueous humor level was 0.23 ± 0.11 &mgr;g/mL (n = 44). Conclusion: Topically applied levofloxacin had better penetration into the aqueous humor than lomefloxacin and norfloxacin.

Quantitative evaluation of tear meniscus height from fluorescein photographs

Purpose: To describe a method of quantifying the tear meniscus height (TMH) and using these values to diagnose patients with dry eye. Methods: Thirty-eight eyes of 19 healthy subjects and 14 patients diagnosed with dry eye were studied. Each eye received 2 μL of 1% fluorescein-sodium solution in the conjunctival sac, and digital photographs were taken of the external surface of the eye with a fundus camera. The tear meniscus was extracted from the digitalized image and used to measure the TMH with NIH image software. The correlation between the mean TMH and Schirmer test values or cotton-thread test values was evaluated. Results: The means of the upper and lower TMH in healthy subjects were 0.22 ± 0.06 and 0.24 ± 0.08 mm, respectively. The comparable values in patients with dry eye were 0.17 ± 0.04 and 0.17 ± 0.07 mm (upper TMS, P = 0.01; lower TMH, P = 0.04; unpaired t test). A significant correlation was found between the TMH and Schirmer test values (r = 0.72, P = 0.01) but not with cotton-thread test values. Conclusions: Fluorescein photographs of the eye can be used to quantify the upper and lower TMH separately and simultaneously without specialized equipment. This technique can be used for the diagnosis of dry eye.

Expression and localization of aging markers in lacrimal gland of chronic graft-versus-host disease

Aging is commonly defined as the accumulation of diverse deleterious changes in cells and tissues with advancing age. To investigate whether aging changes are involved in the lacrimal glands of chronic graft-versus-host disease (cGVHD) model mice, we obtained the specimens from cGVHD model mice, untreated aged and young mice, and examined by histopathology, and immunoblotting. Oxidative stress markers, 8-OHdG, 4-HNE, and hexonoyl lesion (HEL), and other aging markers, p16 and p38, were used to assess the samples. The infiltrating mononuclear cells and endothelia of capillaries in the cGVHD and aged mice expressed the oxidative stress markers and other aging markers, but not in the young mice. Histological changes and the expression of aging markers in the samples from cGVHD mice exhibited similar features to those in aging mice. These results suggest that changes that typically appear with advanced age occur earlier in the lives of mice with lacrimal gland cGVHD.

Evaluation of corneal endothelial pump function with a cold stress test.

Purpose: This study was designed to evaluate corneal endothelial pump function with a cold-stress test. Methods: The study group was comprised of 16 healthy volunteers (20 eyes), 12 patients with penetrating keratoplasty (15 eyes), 9 patients with decreased corneal sensitivity (9 eyes), and 7 patients with corneal endothelial anomaly (10 eyes). After measuring central corneal sensitivity, endothelial cell density, temperature, and thickness, cold stress was applied for 10 minutes and corneal temperature and thickness were measured again. Results: After cooling, the average corneal temperature decreased from 34.7°C to 26.0°C. The degree of corneal swelling (percent increase in thickness) for the control, penetrating keratoplasty, decreased corneal sensitivity, and corneal endothelial anomaly groups was 1.25 ± 0.89, 3.37 ± 2.44, 4.72 ± 2.51, and 3.40 ± 1.92 (% ± standard deviation), respectively. There was a negative correlation between the degree of corneal swelling and corneal sensitivity, but not endothelial cell density, temperature, or thickness. Conclusion: Corneal sensitivity is an effective factor in assessing endothelial pump function.

Control of structural transition in FeSe 1− x Te x thin films by changing substrate materials

Iron chalcogenide superconductors FeSe1−xTex are important materials for investigating the relation be-tween the superconductivity and the orbital and/or electronic nematic order, because the end member material FeSe exhibits a structural transition without a magnetic phase transition. However, the phase separation occurs in the region of 0.1 ≤ x ≤ 0.4 for bulk samples, and it prevents the complete understanding of this system. Here, we report the successful fabrication of epitaxial thin films of FeSe1−xTex with 0 ≤ x ≤ 0.7, which includes the phase-separation region, on LaAlO3 substrates via pulsed laser deposition. In the temperature dependences of differential resistivity for these films with 0 ≤ x ≤ 0.3, the dip- or peak- anomalies, which are well-known to be originated from the structural transition in FeSebulk samples, are observed at the characteristic temperatures, T*. The doping-temperature (x–T) phase diagram of FeSe1−xTex films clearly shows that T* decreases with increasing x, and that Tc suddenly changes at a certain Te content where T* disappears, which turns out to be commonly observed for both films on LaAlO3 and CaF2. These indicate the importance of controlling the structural transition to achieve high Tc in iron chalcogenides.