Meibomian Gland Performance in Glaucomatous Patients With Long-term Instillation of IOP-lowering Medications.

PURPOSE: To investigate the meibomian gland (MG) performance in patients with glaucoma under topical intraocular pressure (IOP)-lowering medications. MATERIALS AND METHODS: This was a cross-sectional case-control study. Patients with glaucoma under different dosages and instillation periods of topical IOP-lowering medications were included. A total of 30 eyes out of 30 healthy participants and 85 eyes out of 85 patients with glaucoma were analyzed. The burden of instilling antiglaucoma agents [burden of antiglaucoma (BAG)] was simply scored for each participant based on the number, formula, frequency, and duration of topical IOP-lowering medications used. All participants completed the MG and tear assessments, including Standard Patient Evaluation of Eye Dryness questionnaire, lipid layer thickness, MG secretion and dropout, Schirmer test, tear break-up time, and blinking patterns. RESULTS: Patients with glaucoma had significantly lower Standard Patient Evaluation of Eye Dryness scores, thinner lipid layer thickness, worse mebium quality, and lower MG secretion compared with healthy participants. Among the patients with glaucoma, MG loss ratio (P=0.006) and meiboscale (P=0.017) were significantly correlated with the BAG score. Compared with the low BAG group (score <80), the high BAG group (score ≥80) had significantly shorter tear break-up time (P=0.047), lower MG density (P=0.032), higher MG loss ratio (P=0.011), and higher meiboscale (P=0.036). CONCLUSIONS: Patients with a higher BAG agents had more unstable tear films and more severe MG dropout. Therefore, MG disease should be particularly observed in patients with glaucoma following a higher BAG regimen.

A DNA dot hybridization model for molecular diagnosis of parasitic keratitis.

PURPOSE: Developing a DNA dot hybridization model for diagnosing parasitic keratitis. METHODS: Newly designed oligonucleotide probes for detecting Acanthamoeba and microsporidia were tested with target reference strains of Acanthamoeba (n = 20) and microsporidia (n = 3), and non-target microorganisms, including bacteria (n = 20) and fungi (n = 20). These probes, which had passed the preliminary tests, were then assembled as a parasite dot hybridization (PDH) model for assessing 33 clinical samples from patients with clinically suspected Acanthamoeba and microsporidia keratitis, including eight positives for Acanthamoeba, 13 positives for microsporidia, and 12 negatives for both pathogens. RESULTS: Two probes for detecting Acanthamoeba and two for detecting microsporidia passed the tests using target and non-target strains and then were assembled in the PDH model. For clinical samples, one Acanthamoeba-positive sample (proved with pathology) was falsely negative according to the PDH assay. The sensitivity and specificity of the PDH assay for diagnosing Acanthamoeba keratitis were 87.5% and 100%, respectively, while the sensitivity and specificity for diagnosing microsporidia keratitis were 100%. The infectious agent of all clinical samples of microsporidia keratitis was identified as Vittaforma corneae with DNA sequencing, while those of Acanthamoeba keratitis were caused by four species of Acanthamoeba, with Acanthamoeba castellanii found in four samples (50%, 4/8). CONCLUSIONS: The PDH model has the potential to be a molecular assay for diagnosing Acanthamoeba and microsporidia keratitis. However, a prospective clinical study might be needed before the model is adopted in routine clinical practice.

A dot hybridization assay for the diagnosis of bacterial keratitis.

PURPOSE: To evaluate a bacterial dot hybridization (BDH) assay for the diagnosis of bacterial keratitis (BK). METHODS: Sixty-one qualified corneal scrapings from 61 patients with suspected microbial keratitis were collected consecutively and prospectively. Among the 61 patients, 16 cases were BK and 45 cases were non-BK, including fungal keratitis, viral keratitis, parasitic keratitis, and non-microbial keratitis. Molecular diagnosis of BK in these corneal scrapes was performed using the BDH assay with three universal bacterial probes (PB1, PB2, and PB3) and three genus-specific probes (Aci, Klb, and Psu) to detect Acinetobacter, Klebsiella, and Pseudomonas, respectively. Signals were standardized after grayscale image transformation for objective validation using receiver operating characteristic (ROC) curves. RESULTS: The standardized intensities for the three universal probes differed statistically significantly between the BK group and the non-BK group. Based on the ROC curves, the sensitivities of PB1, PB2, and PB3 were 81.3%, 81.3%, and 93.8%, and the specificities were 71.1%, 88.9%, and 91.1%, respectively. The sensitivity and specificity of the Psu probe were 92% and 100%, respectively, while those of the Aci and Klb probes could not be estimated because there were no BK cases caused by Acinetobacter spp. or Klebsiella spp. CONCLUSIONS: The BDH assay is an effective molecular approach to improve the diagnosis of BK. Because the bias from bacterial contamination on the ocular surface can be minimized with signal standardization, the assay has the potential to be adopted for routine clinical practice.

Bacterial Bioburden Decrease in Orthokeratology Lens Storage Cases After Forewarning: Assessment by the DNA Dot Hybridization Assay.

BACKGROUND: The aim of this study was to measure the changes in the bacterial bioburden in orthokeratology (OK) lens storage cases using the DNA dot hybridization assay (DHA) after forewarning patients about their bacterial contamination severity. METHODS: Thirty-one OK lens wearers were prospectively enrolled in this study. Dot hybridization assay was used for serial measurements of bacterial bioburden in OK storage cases after lenses had been soaked for approximately 6 hr. After the first assessment, the lens wearers were informed of the extent of case contamination and the possible risk of microbial keratitis (MK), and best practices for lens care and lens case hygiene were reviewed and reinforced. A second assessment by the same DHA method was performed after approximately 6 months. RESULTS: Two universal bacterial probes confirmed a significant decrease in bacterial bioburden at the second assessment (P<0.01 and P<0.001). Genus-specific probes showed significant reductions in Acinetobacter and Klebsiella (P=0.02 and P=0.01), but not in Pseudomonas (P=0.42). CONCLUSIONS: Making OK lens wearers aware of the bacterial bioburden in their lens cases resulted in improved quality of case care and reduced bioburden. Our results suggest that a strategy of bioburden assessment with forewarning could be a useful method to decrease the incidence of OK-related MK.

A Multiplex Dot Hybridization Assay For Detection and Differentiation of Acanthamoeba and Herpes Keratitis.

PURPOSE: We verified a multiplex dot hybridization (MDH) assay for the rapid detection and differentiation of Acanthamoeba keratitis (AK) and herpes simplex keratitis (HSK). METHODS: Molecular detection of Acanthamoeba and herpes simplex virus in corneal scrapes was performed with the MDH assay and standard diagnostic methods. The experimental group included corneal scrapes (n = 33) from patients with culture- or pathology-confirmed AK (n = 15) and real-time PCR-confirmed HSK (n = 16). The control group included 50 samples from cases of bacterial keratitis (n = 15), fungal keratitis (n = 15), and initially presumed AK (n = 5) or HSK (n = 17) which finally were excluded by culture for Acanthamoeba or by real-time PCR for herpes simplex virus, respectively. Discrepant results between methods were resolved by DNA sequencing of the PCR amplicons. RESULTS: After discrepant analysis, the sensitivity for the diagnosis of AK and HSK was both 93.3% by the MDH assay, while the specificity was 100% for the two types of keratitis. The turnaround time of MDH assay was within a working day using an already prepared array. Two false-negatives (one AK case and one HSK case) were obtained by the MDH assay. CONCLUSIONS: The MDH assay could effectively prevent missed or delayed diagnosis of AK and HSK and has a potential to be adopted in routine clinical practice if the test is commercialized.

PCR analysis for assessment of bacterial bioburden in orthokeratology lens cases.

PURPOSE: To develop a PCR gel analysis method for assessing the bacterial bioburden in orthokeratology contact lens (OK) case fluid determined by culture. METHODS: A prospective study with the participation of 41 OK wearers (20 girls, 21 boys) was performed. The mean OK-wearing experience was 3.5±1.9 years. PCR was used to assess the bacterial bioburden (colony-forming units per milliliter) of OK after removal and soaking in the storage case for 6 h. The signal intensity of the PCR bands was analyzed after grayscale image transformation. The difference (cPCR-d) and ratio (cPCR-r) between a PCR signal and its background were used as two standardized indices of PCR signals. The association between the two indices of the PCR signals and the bacterial bioburden determined by culture were analyzed with Pearson's correlation coefficient (r) and receiver operating characteristic (ROC) plots. RESULTS: At least one microbe was isolated from the OK lens case from 38 of the 41 subjects. Both cPCR-d and cPCR-r showed strong correlations with the bacterial bioburden (r>0.7, p<0.0001). ROC analysis enabled good determination of the cutoff values for the two PCR indices with acceptable sensitivity and specificity (78-89%) to assess the degree of bacterial contamination. CONCLUSIONS: The high microbial contamination rate of the OK lens cases revealed the general inappropriate lens care by OK wearers. PCR analysis provides an alternative and rapid method for assessing the bacterial bioburden of OK lens cases, and these results should serve as a warning to OK wearers to follow appropriate lens care procedures to prevent infection.

Microbial Bioburden of Orthokeratology Contact Lens Care System.

OBJECTIVE: To assess the bioburden in an orthokeratology contact lens (OK) care system (defined by microbial identification from OK case fluid) and to identify the risk factors causing high bioburden for pediatric OK wearers in southern Taiwan. METHODS: A prospective study for the investigation of bioburden in the OK care system was performed in a tertiary medical center in southern Taiwan. Microbial isolates from the case fluids soaking OKs were analyzed, and pathogenicity was determined. Age, gender, OK experiences, and contact lens care habits were considered the potential risk factors of microbial bioburden (colony-forming units per milliliter) for causal analysis. RESULTS: Forty-one OK wearers (20 female and 21 male subjects) participated in this study. The mean age was 12.7 years, and the mean OK-wearing experience was 3.5 years. A total of 86 microbial strains were isolated from 38 culture-positive specimens. Frequently reported pathogens in contact lens-related microbial keratitis were less common in the current study, but still present, including 4 strains (5%) of Serratia marcescens, 1 strain (1%) of Pseudomonas aeruginosa, and 1 strain (1%) of Staphylococcus aureus. Microbial bioburden of the OK care system was significantly higher (P<0.05) in male subjects. CONCLUSIONS: The contamination rate of the OK care system was high, and many isolated microorganisms had potential pathogenicity. Reinforcement of proper contact lens care and education should be mandatory for OK wearers, particularly for male subjects, to decrease the risk of high bioburden of the OK care system.

A DNA dot hybridization model for assessment of bacterial bioburden in orthokeratology lens storage cases.

PURPOSE: The aim of this study was to evaluate a DNA dot hybridization assay (DHA) for assessing bacterial bioburden in orthokeratology lens (OK) storage cases. METHODS: Forty-one OK wearers participated in this study. The dot hybridization assay was used to assess the bacterial bioburden of OK after removal and 6-hour soaking in a storage case. Signals of the DHA were standardized after gray image transformation. The correlations between the hybridization intensities of three universal bacteria probes (BP1, BP2, and BP3) and bacterial bioburden determined by culture (colony forming units per milliliter) was analyzed by Pearson's correlation coefficient and receiver operating characteristic plots. In addition, three genus-specific probes for Pseudomonas, Acinetobacter, and Klebsiella were used to detect potentially hazardous bacterial contamination regardless of bacterial viability status. RESULTS: Among the three universal probes, there were good correlations between probe BP2 (r2 = 0.31, P = 9.5 × 10(-5)) and probe BP3 (r2 = 0.35, P = 3.1 × 10(-5)) with bacterial bioburden, but no correlation was found between probe BP1 and bacterial bioburden (r2 = 0.04, P = 0.11). In 41 samples, one was Pseudomonas-positive by both DHA and culture, while 10 were Pseudomonas-positive by DHA but negative by culture. Furthermore, nine samples tested positive for Acinetobacter (n = 7) and Klebsiella (n = 2) by DHA only. CONCLUSIONS: The dot hybridization assay provides a novel way to assess the bacterial bioburden of OK storage cases. Lens care quality can be assessed with universal bacteria probes, while potentially hazardous bacterial contamination can be traced with genus-specific probes.

Increased Dickkopf-1 expression accelerates bone cell apoptosis in femoral head osteonecrosis.

Intensive bone cell apoptosis contributes to osteonecrosis of femoral head (ONFH). Dickkopf-1 (DKK1) reportedly mediates various types of skeletal disorders. This study investigated whether DKK1 was linked to the occurrence of ONFH. Thirty-nine patients with various stages of ONFH were recruited. Bone specimens were harvested from 34 ONFH patients underwent hip arthroplasty, and from 10 femoral neck fracture patients. Bad, Bcl2 TNFalpha, DKK1, Wnt3a, LRP5, and Axin1 expressions were analyzed by quantitative RT-PCR and ELISA. Apoptotic cells were assayed using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labelling (TUNEL). Primary bone-marrow mesenchymal cells were treated with DKK1 RNA interference and recombinant DKK1 protein. ONFH patients with the histories of being administrated corticosteroids and excessive alcohol consumption had significantly higher Bad and DKK1 mRNA expressions in bone tissue and DKK1 abundances in serum than femoral neck fracture patients. Bone cells adjacent to osteonecrotic bone displayed strong DKK1 immunoreactivity and TUNEL staining. Increased DKK1 expression in bone tissue and serum correlated with Bad expression and TUNEL staining. Serum DKK1 abundance correlated with the severity of ONFH. The DKK1 RNA interference and recombinant DKK1 protein regulated Bad expression and apoptosis of primary bone-marrow mesenchymal cells. Knock down of DKK1 reduced dexamethasone-induced apoptosis of mesenchymal cells. Taken together, promoted DKK1 expression was associated with bone cell apoptosis in the occurrence of ONFH patients with the histories of corticosteroid and alcohol intake and progression of ONFH. DKK1 expression in injured tissue provides new insight into ONFH pathogenesis.

Increased IL-1beta expression and myofibroblast recruitment in subacromial bursa is associated with rotator cuff lesions with shoulder stiffness.

We evaluated whether proinflammatory cytokine expression and myofibroblast recruitment in subacromial bursa was linked to rotator cuff lesions with shoulder stiffness. We analyzed expressions of IL-1beta, IL-6, and TNF-alpha in subacromial bursa and joint fluid collected from 14 patients with cuff tears with stiffness as a study group (Group I) and 14 patients with rotator cuff tears without shoulder stiffness as a control group (Group II) using real-time RT-PCR, immunohistochemistry, and ELISA. Myofibroblast apoptosis in subacromial bursa was analyzed using terminal deoxynucleotidyl transferase -mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) and alpha-smooth muscle actin immunofluorescence staining. Shoulder function was evaluated using the Constant score. Group I had higher mRNA expression (p < 0.001) and immunoreactivities (p < 0.001) of IL-1beta. They also had higher levels of IL-1beta, IL-6, and TNF-alpha in joint fluid. Increased IL-1beta mRNA expression in the subacromial bursa and IL-1beta levels in joint fluid were correlated with a preoperative deficit in shoulder motion (p < 0.001) and preoperative Constant scores (p < 0.001). Immunofluorescence observations showed that Group I subjects had more myofibroblasts (p < 0.001) than Group II. In Group II, a significant correlation was found between apoptotic myofibroblasts and total myofibroblasts (p = 0.002), but not in Group I (p = 0.510). Increased expression of IL-1beta and myofibroblast recruitment in the subacromial bursa in rotator cuff lesions are linked to shoulder stiffness.