Biomedical subjects

William L Miller

Publications and source records attributed to William L Miller.

At least 19 recordsLinked to original sources

PubMed2006

Size-dependent spectroscopic properties of conjugated polymer nanoparticles.

This paper is focused on how the spectroscopic properties of conjugated polymers evolve in the size range between single polymer chains and the bulk material. The measurements used single-particle spectroscopy techniques and include both static and dynamic measurements. The main observation of this work is that the spectroscopic properties of MEH-PPV evolve rapidly as a function of nanoparticle size and achieve bulk-like properties for nanoparticles greater than 10 nm in size. Nanoparticles were assembled by a reprecipitation technique and characterized by fluorescence emission spectroscopy. The physical origin of the size-dependent spectroscopic properties is assigned to the distance dependence of four main processes: electronic energy transfer between blue and red sites, triplet-triplet annihilation, singlet exciton quenching by triplets, and singlet exciton quenching by hole polarons.

Journal Article↗

PubMed2006

Rapid targeting followed by sustained deployment of visual spatial attention.

We investigated preparatory attention processes when a spatial discrimination was required at a cued location, by measuring electroencephalography following a central symbolic cue to deploy spatial attention. Electroencephalography activity in response to the cue revealed three cue-related activations: an early-onset positivity following the P1 at posterior scalp sites contralateral to the cued location, followed by cue-related frontal scalp activity and later-onset sustained activity at posterior scalp sites contralateral to the cued location. The early contralateral positivity may reflect rapid targeting of the cued location. Our results also extend the findings of cue-related frontal activity followed by posterior activity contralateral to the cued location, found with nonspatial feature discriminations, to a task requiring a spatial discrimination.

Adult↗

PubMed2006

Effect of temperature and chain length on the bimodal emission properties of single polyfluorene copolymer molecules.

Fluorescence emission spectra were recorded for isolated polymer chains of the polyfluorene copolymer, F8BT [poly(9,9-di-n-octylfluorene-alt-benzothiadiazole)], at 298 and 20 K for two molecular weights (chain lengths). For long-chain F8BT at 298 K, the observed distribution of single-molecule emission maxima G(Emax) is bimodal, with peaks at approximately 2.35 eV ("blue") and approximately 2.25 eV ("red"). Previously, the red forms have been assigned to polymer chains that possess intrachain contacts, which lowers the local singlet exciton energy. At approximately 20 K, G(Emax) collapses into a single broad distribution centered at approximately 2.3 eV for long-chain F8BT. However, this distribution can be further divided into a high-energy edge that is dominated by the "blue" form, while the remainder of the distribution is composed of the "red" form. Low-molecular-weight F8BT samples emit exclusively from the blue form, and no shift in peak maxima with low temperature was observed. A Franck-Condon analysis reveals a decrease in emitting state displacements between spectra measured at 298 and 20 K, suggesting that temperature-induced structural displacements are responsible for the change in the bimodal emission.

Journal Article↗

PubMed2006

Acute corneal hydrops: a case report including confocal and histopathological considerations.

This is a case report of corneal hydrops associated with keratoconus with a review of current literature pertaining to diagnosis, histopathology, and treatment options. A 30-year-old African American male presented to the University Eye Institute with acute unilateral pain, redness, and visual impairment. His symptoms, clinical presentation and past diagnosis of keratoconus confirmed his condition to be acute corneal hydrops (CH). The condition was closely followed utilizing topical treatment including hyper-osmotic (Muro 128) and non-steroidal anti-inflammatory agents (Acular and Voltaren). After 4 months, the patient's condition resolved but subsequent corneal scarring resulted. Corneal ectasia in patients with keratoconus may progress into acute rupture of the posterior limiting lamina (PLL) and the endothelium, resulting in CH, which may manifest as an area of edematous and opacified cornea lasting up to 4 months in duration. Acute complications such as CH seldom occur. Histopathology and confocal microscopy can be used to help visualize and understand CH on a cellular level. After regeneration of the corneal structures, central scarring may limit visual acuity and necessitate a corneal transplant.

Acute Disease↗

PubMed2006

Conjunctival cytokine expression in symptomatic moderate dry eye subjects.

PURPOSE: To compare ocular surface cytokine expression in healthy controls and subjects with moderate dry eye and to study the ability of interleukin (IL)-1beta to modulate cytokine expression in cultured human conjunctival epithelial cells (CECs). METHODS: Subjective (symptom questionnaire) and objective (tear osmolality, fluorescein tear break-up time [TBUT]) measures of dry eye were determined in five healthy controls and five subjects with moderate dry eye. Tear clearance rates were measured with a fluorophotometer. Enzyme immunoassay and a cytokine bead assay were used to quantify IL-1beta in tear fluid. RT-PCR was performed to detect expression of IL-1beta, IL-6, IL-8, growth-related oncogene (GRO)-beta, intercellular adhesion molecule (ICAM)-1, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), and ephrin A5 in conjunctival impression cytology (CIC) samples and in CECs (IOBA-NHC cell line, n=3; primary cultured CEC, n=3) exposed to 10 ng/mL IL-1beta for 6 hours. RESULTS: Subjects with moderate dry eye had significantly higher symptom scores, higher tear osmolality, and shorter TBUT than healthy controls. Subjects with dry eye demonstrated slightly slower tear clearance (13.1% per minute) than healthy controls (15.4% per minute). Very low levels of IL-1beta protein were detected in the tear fluid of both groups. TRAIL was constitutively expressed in CIC samples, whereas IL-1beta, IL-6, and GRO-beta were absent. Weak expression of IL-8 (two healthy, four dry eye), ICAM-1 (four healthy, four dry eye), and ephrin A5 (one healthy, two dry eye) was observed. IL-1beta upregulated its own expression and that of IL-6, IL-8, GRO-beta, and ICAM-1 in cultured CECs but not that of ephrin A5 or TRAIL. CONCLUSIONS: The lack of major differences in ocular surface cytokine expression between the two groups of subjects implies other inflammatory pathways or etiologies are involved in moderate dry eye. Although IL-1beta modulated the expression of various cytokines in cultured CECs, its absence in tear fluid and CIC samples suggests that IL-1beta does not play a modulatory role in moderate dry eye.

Adult↗

PubMed2005

Differential regulation of follicle stimulating hormone by activin A and TGFB1 in murine gonadotropes.

BACKGROUND: Activins stimulate the synthesis of follicle stimulating hormone (FSH) in pituitary gonadotropes, at least in part, by inducing transcription of its beta subunit (Fshb). Evidence from several laboratories studying transformed murine LbetaT2 gonadotropes indicates that activins signal through Smad-dependent and/or Smad-independent pathways, similar to those used by transforming growth factor beta-1 (TGFB1) in other cell types. Therefore, given common intracellular signaling mechanisms of these two ligands, we examined whether TGFBs can also induce transcription of Fshb in LbetaT2 cells as well as in purified primary murine gonadotropes. METHODS: Murine Fshb promoter-reporter (-1990/+1 mFshb-luc) activity was measured in LbetaT2 cells treated with activin A or TGFB1, and in cells transfected with either activin or TGFB receptors. The ability of the ligands to stimulate phosphorylation of Smads 2 and 3 in LbetaT2 cells was measured by western blot analysis, and expression of TGFB type I and II receptors was assessed by reverse transcriptase polymerase chain reaction in both LbetaT2 cells and primary gonadotropes purified from male mice of different ages. Finally, regulation of endogenous murine Fshb mRNA levels by activin A and TGFB1 in purified gonadotropes and whole pituitary cultures was measured using quantitative RT-PCR. RESULTS: Activin A dose-dependently stimulated -1990/+1 mFshb-luc activity in LbetaT2 cells, but TGFB1 had no effect at doses up to 5 nM. Similarly, activin A, but not TGFB1, stimulated Smad 2 and 3 phosphorylation in these cells. Constitutively active forms of the activin (Acvr1b-T206D) and TGFB (TGFBR1-T204D) type I receptors strongly stimulated -1990/+1 mFshb-luc activity, showing that mechanisms down stream of Tgfbr1 seem to be intact in LbetaT2 cells. RT-PCR analysis of LbetaT2 cells and whole adult murine pituitaries indicated that both expressed Tgfbr1 mRNA, but that Tgfbr2 was not detected in LbetaT2 cells. When cells were transfected with a human TGFBR2 expression construct, TGFB1 acquired the ability to significantly stimulate -1990/+1 mFshb-luc activity. In contrast to LbetaT2 cells, primary murine gonadotropes from young mice (8-10 weeks) contained low, but detectable levels of Tgfbr2 mRNA and these levels increased in older mice (1 yr). A second surprise was the finding that treatment of purified primary gonadotropes with TGFB1 decreased murine Fshb mRNA expression by 95% whereas activin A stimulated expression by 31-fold. CONCLUSION: These data indicate that TGFB1-insensitivity in LbetaT2 cells results from a deficiency in Tgfbr2 expression. In primary gonadotropes, however, expression of Tgfbr2 does occur, and its presence permits TGFB1 to inhibit Fshb transcription, whereas activin A stimulates it. These divergent actions of activin A and TGFB1 were unexpected and show that the two ligands may act through distinct pathways to cause opposing biological effects in primary murine gonadotropes.

Activins↗

PubMed2005

Photodegradation of dimethyl sulfide (DMS) in natural waters: laboratory assessment of the nitrate-photolysis-induced DMS oxidation.

The interaction of sunlight and dissolved chromophoric matter produces reactive chemical species that are significant in the removal of dimethyl sulfide (DMS) in the surface ocean. Using artificial solar radiation, we examined the role of several inorganic components of seawater on the kinetics of NO3- -photolysis-induced DMS removal in aqueous solution. This study strongly suggests that NO3- photolysis products react significantly with DMS in aqueous solution possibly via an electrophilic attack on the electron-rich sulfur atom. This supports previous field observations that indicate that NO3- photolysis has a substantial control on DMS photochemistry in nutrient-rich waters. A key finding of this research is that the oxidation rate of DMS induced by NO3- photolysis is dramatically enhanced in the presence of bromide ion. Moreover, our results suggest that bicarbonate/carbonate ions are involved in free radical production/scavenging processes important for DMS photochemistry. These reactions are pH dependent. We propose that DMS removal by some selective free radicals derived from bromide and bicarbonate/carbonate ion oxidation is a potentially important and previously unrecognized pathway for DMS photodegradation in marine waters.

Biodegradation, Environmental↗

PubMed2005

Transforming growth factor beta-activated kinase 1 is a key mediator of ovine follicle-stimulating hormone beta-subunit expression.

FSH, a key regulator of gonadal function, contains a beta-subunit (FSHbeta) that is transcriptionally induced by activin, a member of the TGFbeta-superfamily. This study used 4.7 kb of the ovine FSHbeta-promoter linked to luciferase (oFSHbetaLuc) plus a well-characterized activin-responsive construct, p3TPLuc, to investigate the hypothesis that Smad3, TGFbeta-activated kinase 1 (TAK1), or both cause activin-mediated induction of FSH. Overexpression of either Smad3 or TAK1 induced oFSHbetaLuc in gonadotrope-derived LbetaT2 cells as much as activin itself. Induction of p3TPLuc by activin is known to require Smad3 activation in many cell types, and this was true in LbetaT2 cells, where 10-fold induction by activin (2-8 h after activin treatment) was blocked more than 90% by two dominant negative (DN) inhibitors of Smad3 [DN-Smad3 (3SA) and DN-Smad3 (D407E)]. By contrast, 6.5-fold induction of oFSHbetaLuc by activin (10-24 h after activin treatment) was not blocked by either DN-Smad inhibitor, suggesting that activation of Smad3 did not trigger induction of oFSHbetaLuc. By contrast, inhibition of TAK1 by a DN-TAK1 construct led to a 50% decrease in activin-mediated induction of oFSHbetaLuc, and a specific inhibitor of TAK1 (5Z-7-Oxozeanol) blocked induction by 100%, indicating that TAK1 is necessary for activin induction of oFSHbetaLuc. Finally, inhibiting p38-MAPK (often activated by TAK1) blocked induction of oFSHbetaLuc by 60%. In conclusion, the data presented here indicate that activation of TAK1 (and probably p38-MAPK), but not Smad3, is necessary for triggering induction of oFSHbeta by activin.

Activins↗

PubMed2005

Conditional induction of ovulation in mice.

Follicle-stimulating hormone controls the maturation of mammalian ovarian follicles. In excess, it can increase ovulation (egg production). Reported here is a transgenic doxycycline-activated switch, tested in mice, that produced more FSHB subunit (therefore more FSH) and increased ovulation by the simple feeding of doxycycline (Dox). The transgenic switch was expressed selectively in pituitary gonadotropes and was designed to enhance normal expression of FSH when exposed to Dox, but to be regulated by all the hormones that normally control FSH production in vivo. Feeding maximally effective levels of Dox increased overall mRNA for FSHB and serum FSH by over half in males, and Dox treatment more than doubled the normal ovulation rate of female mice for up to 10 reproductive cycles. Lower levels of Dox increased the number of developing embryos by 30%. Ovarian structure and function appeared normal. In summary, gene switch technology and normal FSH regulation were combined to effectively enhance ovulation in mice. Theoretically, the same strategy can be used with any genetic switch to increase ovulation (or any highly conserved physiology) in any mammal.

Animals↗

PubMed2005

How complexity science can inform a reflective process for improvement in primary care practices.

BACKGROUND: Quality improvement processes have sometimes met with limited success in small, independent primary care settings. The theoretical framework for these processes uses an implied understanding of organizations as predictable with potentially controllable components. However, most organizations are not accurately described using this framework. Complexity science provides a better fit for understanding small primary care practices. METHODS: The Multimethod Assessment Process (MAP)/Reflective Adaptive Process (RAP) is informed by complexity science. This process was developed in a series of studies designed to understand and improve primary care practice. A case example illustrates the application and impact of the MAP/RAP process. RESULTS: Guiding principles for a reflective change process include the following: an understanding of practices' vision and mission is useful in guiding change, learning and reflection helps organizations adapt to and plan change, tension and discomfort are essential and normal during change, and diverse perspectives foster adaptability and new insights for positive change. DISCUSSION: A reflective change process that treats organizations as complex adaptive systems may help practices make sustainable improvements.

Organizational Case Studies↗

PubMed2005

Healing landscapes: patients, relationships, and creating optimal healing places.

Healing can be both an intensely personal and a social and community event that often surprises us when it emerges from the landscape of everyday life. This observation raises at least three questions that serve as the focus for this paper's reflections about creating optimal healing places. Who are patients? What relationships and features of those relationships help patients toward healing? How do we understand and facilitate the emergence of healing over time and place? Using existing literature and our own past and current studies of patients, clinical encounters, and primary care practices, we explore each of these questions. We identify four different aspects or faces of patients: patients as human animals, patients as persons, patients as techno-consumers, and patients as patients. We highlight 10 lessons or observations about patients and their healing experiences. Key features of relational process are described, and nine interdependent relationship characteristics that appear to promote healing are discussed. The idea of healing landscapes as an emergent life space is introduced as a way of conceptualizing and further investigating these observations. A reflective action process for facilitating the emergence of healing landscapes and creating an ecology of hope is presented, and recommendations for future research are briefly shared.

Environment Design↗

PubMed2005

The diagnosis and characteristics of moderate dry eye in non-contact lens wearers.

PURPOSE: To identify and characterize moderate dry eye in non-contact lens wearers with a new scoring system-based dry eye questionnaire and to determine which objective tests better differentiate patients with moderate dry eye from healthy patients. METHODS: Fifty-two healthy subjects (21 women and 31 men with a mean age of 27.8 +/- 9.2 years) and 37 subjects with moderate dry eye (33 women and 4 men with a mean age of 36.4 +/- 12.9 years) completed a 42-item dry eye questionnaire. Seventeen healthy subjects (11 women and 6 men with a mean age of 30.5 +/- 9.7 years) and 28 subjects with moderate dry eye (24 women and 4 men with a mean age of 38.50 +/- 3.8 years) underwent additional objective assessment of ocular surface health, tear osmolality, tear stability, and tear volume. RESULTS: Subjects with moderate dry eye scored significantly higher (49.8 +/- 20.3, P<0.0001) on the dry eye questionnaire than did normal subjects (11.7 +/- 10.3). Ocular irritation symptoms worsened with progression of time of day in both groups of subjects. Internal reliability (0.95 Cronbach alpha) was excellent, and concurrent validity (Spearman rho 0.507) was acceptable when compared to the McMonnies and Ho dry eye questionnaire. Significant differences in tear osmolality (P<0.00001), invasive tear breakup time (P<0.034), and corneal vital dye staining (P<0.0001) were detected between the two groups of subjects. A stepwise linear regression on objective clinical tests, however, did not account for 77% of the total variance in the questionnaire scores. CONCLUSIONS: A unique scoring system-based dry eye questionnaire was validated to separate non-contact lens wearers with moderate dry eye from healthy subjects. Objective tests of tear osmolality and stability and ocular surface integrity were better than other clinical measures at identifying differences between the two subject groups. The results strongly support the evidence that the diagnosis and treatment of moderate dry eye requires a detailed assessment of self-perceived symptoms and that objective clinical testing alone may be insufficient.

Adolescent↗

PubMed2004

Rapid, efficient isolation of murine gonadotropes and their use in revealing control of follicle-stimulating hormone by paracrine pituitary factors.

FSH and LH are produced only in gonadotropes, which are reported to comprise 3-12% of mammalian pituitaries. Factors made within the pituitary are powerful regulators of FSH and also influence LH expression, but their identities and cellular origins are unknown because it is impossible to isolate and individually analyze different pituitary cell types. In this study FSH-producing gonadotropes were specifically tagged in vivo with a transgenic cell surface antigen (H-2Kk) so they could be purified in vitro using paramagnetic anti-H-2Kk microbeads. After enzymatic dispersion of pituitary cells, it took 1 h or less to extract 55 +/- 5% of FSH-producing gonadotropes at 95 +/- 0.5% purity, as judged by immunostaining for FSH or prolactin. Although this procedure selected for FSH expression, the isolated gonadotropes were also enriched 22-fold for LH-containing cells. For studies aimed at understanding factors that control FSH transcription, the purified gonadotropes were treated with activin A, which increased FSH expression 480% above basal levels (d 3 of culture). Coincubation of purified gonadotropes with pituitary nongonadotropes increased FSH expression 800% (d 3 of culture). Follistatin, an activin-binding protein, decreased FSH expression 35-50%, suggesting that gonadotropes make some activin and/or other follistatin-sensitive molecule(s) that induce FSH. These data show that paracrine factors from pituitary nongonadotropes can play a major role in controlling FSHbeta at the pituitary level. The study presented here describes a rapid, reliable, and efficient method for isolating any specialized cell type, including all cells that produce endocrine hormones.

Activins↗

PubMed2004

A comparison of tear volume (by tear meniscus height and phenol red thread test) and tear fluid osmolality measures in non-lens wearers and in contact lens wearers.

PURPOSE: Various measures are available to assess the tear film, yet little specific information is available on how they relate to each other. An exploratory study was undertaken to assess three measures and their relationship in non-contact lens wearers and in contact lens wearers. METHODS: Forty-three young subjects (mean age, 25.0 +/- 3.1 years; 19 men and 24 women) without overt ocular disease were recruited and categorized into four similarly sized groups based on contact lens wear (no lens wear, conventional daily wear hydrogels, silicone hydrogel lenses worn on a continuous basis, and gas-permeable contact lenses). Sets of measures, in random order and from both eyes whenever possible, were made using a phenol red thread (PRT) test over 15 seconds (open eye), biomicroscopy to assess tear meniscus height (TMH) from a perpendicular perspective using a 0.05-mm resolution graticule, and a borosilicate glass micropipette used to collect a 5-microL sample of tears for assessment of osmolality by vapor pressure measures. RESULTS: For the complete group of subjects, the TMH data averaged 0.22 +/- 0.07 mm; the average PRT wetting length was 18.0 +/- 6.1 mm; and the tear osmolality averaged 317 +/- 28 mOsm/kg. The intereye differences averaged 0.04 mm for TMH, 3.7 mm for PRT, and 15 mOsm/kg for tear osmolality. There were no detectable sex-related differences in the measures. Compared with the control group (average, 0.25 mm), the TMH data showed a trend to be lower in daily hydrogel (0.21 mm) and silicone hydrogel (0.20 mm) lens wearers, but not in gas-permeable lens wearers (0.24 mm). PRT data was bimodally distributed, with the control group showing slightly higher (average, 21.1 mm) wetting compared with hydrogel lens wearers (16.7 and 17.4 mm) and gas-permeable lens wearers (average, 17.3 mm). Hydrogel (319 mOsm/kg for both groups) and gas-permeable lens wearers (average, 324 mOsm/kg) had higher tear osmolality measures compared with the control group (average, 305 mOsm/kg). Although some of the differences approached statistical significance, any statistical differences were evident only after outliers were removed. However, on pooling all data, there was a statistically significant positive correlation between TMH and open-eye PRT measures (P < 0.001) and an indication of a negative correlation between open-eye PRT and tear osmolality measures. CONCLUSIONS: Even contemporary contact lens wear can have a small but measurable impact on the precorneal tear film osmolality or volume. The changes are internally consistent and, overall, support the idea that the PRT test provides a useful measure of tear meniscus volume.

Adolescent↗

PubMed2004

The Clinical Hand: A curricular map for relationship-centered care.

Learning and teaching the complex craft of relationship-centered care in the context of the competing demands of clinical family medicine can be challenging. The "Clinical Hand" is an educational aid, which serves as a curricular map specifying what content and skills are important for relationship centered care. The Clinical Hand illuminates seven features of the clinical encounter. "Opening the Hand" symbolizes the importance of relationship and healing intention. The "Grip of Power" highlights the significance of locating, owning, aiming, and sharing power in the relationship. The "Wrist Lines of Guidance" name three goals for every visit and three types of clinical encounters. The "Fingers of Direction" identify five sequential tasks for each encounter, and the "Nails for Trouble" remind residents of the BATHE technique. The "Palm of Hope" represents a diagnostic and management tool, and a "Swinging Cultural Ape" emphasizes the importance of evolution, culture, and the need to "keep swinging." The use of the Clinical Hand in a residency program is briefly discussed.

Curriculum↗

PubMed2003

Pituitary tumorigenesis targeted by the ovine follicle-stimulating hormone beta-subunit gene regulatory region in transgenic mice.

Targeted tumorigenesis in transgenic mice has been a powerful tool for the study of gene expression and oncogenesis, as well as for the production of differentiated immortal cell lines from rare cell types. Follicle-stimulating hormone (FSH) is secreted by the gonadotrope cells of the anterior pituitary gland and plays a pivotal role in mammalian reproduction. Here we have used the regulatory region of the ovine FSH beta gene to direct expression of the SV40 T antigen oncogene to gonadotrope cells in the pituitary of transgenic mice. Two of five transgenic mouse lines bearing this fusion gene rapidly developed pituitary tumors, with appearance of adenomatous foci as early as 6 weeks of age, resulting in death by 12 weeks of age in both genders. Histologic examination of tumor development over time revealed that increases in cell proliferation and dysplasia were accompanied by decreases in synthesis of pituitary hormones, indicating dedifferentiation of the pituitary cells. Histological features observed in these tumors were in agreement with this rapid transformation of cell phenotype. Tumors were multifocal in origin, and the most highly transformed cell types observed consisted of giant pale basophilic cells with enormous hyperploid nuclei associated with infiltrating neuronal-like cells, which were very abundant at later stages of tumor development. Mitotic indices were much higher in transgenic than wild-type pituitaries, as expected. Morphologic analysis of the gonads of these transgenic mice showed no major developmental differences, as compared to wild-type littermates, however the length of the seminiferous tubules in transgenic males was greater than age-matched wild-type animals. Despite this phenotype difference, both genders were fertile, with normal sperm development observed in males and normal estrous cycle stages in females. Moreover, while 8 -- 10-week-old transgenic males had much lower blood levels of FSH than littermates, transgenic female FSH levels were the same as those of wild-type females. These animals offer a unique and potentially useful model of organ-specific tumorigenesis, where a multistage pathway of tumor development is evident, both histologically and temporally. Study of such models will advance our knowledge on the physiological and molecular mechanisms involved in gene expression as well as tumor formation.

Animals↗

PubMed2003

Expression of human beta-defensins in conjunctival epithelium: relevance to dry eye disease.

PURPOSE: The goals of this study were to investigate whether beta-defensins are differentially expressed in the conjunctival epithelium of patients with moderate dry eye when compared with normal subjects and whether proinflammatory cytokines or bacteria can modulate the expression of human beta-defensins (hBDs)-1, -2, and -3 by conjunctival epithelial cells. METHODS: RNA extracted from conjunctival impression cytology specimens of eight normal subjects and nine patients with moderate dry eye was used in RT-PCR to detect mRNA for hBDs-1, -2, and -3. Two conjunctival epithelial cell lines and primary cultured conjunctival epithelial cells were treated with proinflammatory cytokines or heat-killed Pseudomonas aeruginosa. RT-PCR and immunoblot analysis were used to detect mRNA for hBD-1, -2, and -3 and protein secretion of hBD-2, respectively. RESULTS: hBD-2 message was detected in RNA samples of eight of nine patients with dry eye, but not in any of the normal subjects' samples, whereas hBD-1 and -3 were detected in all subjects tested. RT-PCR revealed an upregulation of hBD-2 but no difference in expression of hBD-1 and -3 in cultured conjunctival cells after a 24-hour treatment with 10 ng/mL interleukin (IL)-1beta, IL-1beta and tumor necrosis factor-alpha (10 ng/mL) or heat-killed Pseudomonas aeruginosa (1 million colony-forming units; n = 3). hBD-2 expression was upregulated from 4 hours of treatment with IL-1beta (at 10 ng/mL; (n = 2-3) and at a concentration of 0.1 ng/mL IL-1beta (24-hour treatment; n = 2-3). Immunoblots demonstrated protein secretion results corresponding to the RT-PCR data. CONCLUSIONS: hBD-2 was expressed only in the conjunctival epithelium of patients with moderate dry eye. Because cytokines such as IL-1beta and TNF-alpha induced the expression of hBD-2 by conjunctival epithelial cells and because increased proinflammatory cytokine activity is a feature of dry eye disease, it can be speculated that the hBD-2 upregulation observed in subjects with moderate dry eye is mediated by proinflammatory cytokine activity.

Adult↗

PubMed2003

The association of bulbar conjunctival folds with other clinical findings in normal and moderate dry eye subjects.

BACKGROUND: Conjunctival folds have been reported as incidental findings in routine biomicroscopic examination, especially related to patients with dry eye disease. We compared the number of lower temporal lid-parallel conjunctival folds (LIPCOF) in normal and moderate dry-eyed patients with specific biomicroscopic findings (corneal staining, limbal injection, and bulbar conjunctival injection) and tear osmolality. METHODS: Fourteen moderate dry eye subjects (12 female, 2 male; mean age, 43.4 years--range, 23 to 71 years) and eight normal subjects (3 female, 5 male; mean age, 37.25 years--range, 20 to 55 years) participated in this study. Bulbar conjunctival folds were quantified in the temporal aspect of each eye following fluorescein instillation. Tear osmolality was measured with a vapor pressure osmometer. RESULTS: There was a slight difference in the number of bulbar conjunctival folds between the moderate dry eye group and the normal controls (2.07 +/- 2.16 vs. 2.25 +/- 0.70, p = 0.676). Conjunctival folds were not correlated with any of the above parameters nor were they associated with the age of the subject. However, the study did reveal that tear osmolality (p = 0.005), corneal staining (p = 0.019), and conjunctival bulbar injection (p = 0.016) were significantly higher in the moderate dry eye group of subjects (Mann Whitney U Test). A significant correlation (Spearmans rho) was found between limbal injection (r2 = 0.535, p = 0.01) and comeal staining. Age was only found to be correlated with tear osmolality (r2 = 0.520, p = 0.013). CONCLUSIONS: Although there was a small difference in the number of conjunctival folds between normal and moderate dry eye subjects, they do not appear to be as discriminating as other variables measured in the study. Additionally, age does not affect the number of conjunctival folds.

Adult↗