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1.
Cornea ; 42(1): 110-112, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36036669

ABSTRACT

PURPOSE: Outcomes of Acanthamoeba keratitis are often worse in India than in the United States. The goal of this study was to determine whether antiamoebic susceptibility patterns were different when comparing Acanthamoeba isolates from India with those of the United States. METHODS: Acanthamoeba isolates were obtained from corneal scrapings of 43 patients with infectious keratitis seen at the Francis I. Proctor Foundation (N = 23) and Aravind Eye Hospital (N = 20) from 2008 through 2012 and plated on growth media. A previously described minimum cysticidal concentration (MCC) assay was performed by a single laboratory technician to assess susceptibility to 5 antiamoebic agents for all isolates. Testing was conducted in triplicate, with the median MCC chosen for analyses. RESULTS: The MCC (µg/mL) of polyhexamethylene biguanide was 6.25 [IQR 5.47-12.5] for Aravind isolates and 6.25 [IQR 6.25-9.375] for Proctor isolates ( P = 0.75), corresponding values were 6.25 [IQR 3.125-6.25] and 3.125 [IQR 3.125-9.375] for chlorhexidine ( P = 0.81), 2500 [IQR 2500-5000] and 5000 [IQR 1250-20,000] for voriconazole ( P = 0.25), 15.6 [IQR 15.6-39.0625] and 15.6 [IQR 15.6-31.25] for hexamidine ( P = 0.92), and 15.6 [IQR 7.81-15.6] and 15.6 [IQR 7.81-31.25] for propamidine ( P = 0.42). CONCLUSIONS: This study found no statistically significant differences in antiamoebic susceptibility of Indian versus US samples from Acanthamoeba keratitis clinical isolates. These findings suggest that differences in antiamoebic susceptibility are likely not responsible for differential outcomes in Acanthamoeba keratitis between the 2 locations.


Subject(s)
Acanthamoeba Keratitis , Acanthamoeba , Humans , Acanthamoeba Keratitis/drug therapy , Chlorhexidine/pharmacology , Voriconazole/pharmacology , California
3.
Cornea ; 41(11): 1386-1391, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-34743096

ABSTRACT

PURPOSE: The objective of this study was to compare the clinical and microbiological profiles of culture-proven pure Corynebacterium keratitis with mixed infection and their antibiotic susceptibility patterns over a 2-year period. METHODS: A retrospective analysis of culture-proven cases of Corynebacterium keratitis over a 2-year period was performed in 3 different tertiary eye care centers. All isolates were tested for antibiotic susceptibility in vitro using the disc-diffusion method for 7 antibiotics. RESULTS: Altogether 108 cases were identified as culture-positive Corynebacterium keratitis in 3 tertiary eye care centers. Of these, 60.2% (n = 65) and 39.8% (n = 43) of cases were due to pure Corynebacterium and mixed infection, respectively. The mean duration of symptoms was 23.2 ± 29.6 days. In the mixed-infection group, fungus was identified as the coexistent pathogen in 22 cases (51.1%). Ocular surface disorder was the most common risk factor (33.9%) in Corynebacterium keratitis. The most frequently isolated species was Corynebacterium amycolatum (22.2%) in both groups. Therapeutic keratoplasty was performed in 8.3% of cases. There was no significant difference in the outcome between the 2 groups. Cefazolin resistance was seen in 13.9% of patients, and all isolates were susceptible to vancomycin. The resistance pattern showed emerging resistance toward fluoroquinolone because the isolates were resistant to gatifloxacin (58.3%), moxifloxacin (47.2%), ciprofloxacin (54.6%), and ofloxacin (45.4%). CONCLUSIONS: Ocular surface disorder is the most common risk factor in Corynebacterium keratitis. Although fluoroquinolones are commonly used as first-line therapy in microbial keratitis, the in vitro resistance pattern indicates that these are less likely to be effective in infection with Corynebacterium species.


Subject(s)
Coinfection , Eye Infections, Bacterial , Keratitis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Cefazolin , Ciprofloxacin/therapeutic use , Coinfection/drug therapy , Corynebacterium , Eye Infections, Bacterial/drug therapy , Eye Infections, Bacterial/microbiology , Fluoroquinolones/pharmacology , Fluoroquinolones/therapeutic use , Gatifloxacin , Humans , Keratitis/drug therapy , Keratitis/microbiology , Microbial Sensitivity Tests , Moxifloxacin/therapeutic use , Ofloxacin/therapeutic use , Retrospective Studies , Tertiary Care Centers , Vancomycin/therapeutic use
4.
Transl Vis Sci Technol ; 10(5): 6, 2021 04 29.
Article in English | MEDLINE | ID: mdl-34003973

ABSTRACT

Purpose: We aimed to develop a novel chemical cross-linker treatment for keratoconus by reacting dicarboxylic acid spacer molecules and amine functional groups on protein structure of the tissue using carbodi-imide chemistry. We propose this as an alternative to conventional cross-linking treatment for keratoconus. Methods: The study involved optimization of the cross-linker formulation. Mechanical stiffness of ex vivo porcine and human corneas after application of the cross-linker was measured. Histochemical analysis was performed to record changes in gross morphology after cross-linker treatment on ex vivo porcine and human and in vivo rabbit corneas. Terminal deoxynucleotidyl transferase-mediated dUTP-X nick-end-labeling (TUNEL) staining was performed to study apoptotic effects of cross-linker. Cytotoxicity potential of cross-linker was evaluated by studying explant cultures for cellular outgrowth and immunostaining assays on porcine and human corneas after treatment. Results: We demonstrated a clinically relevant increase in stiffness in ex vivo experiments using porcine and human cornea without removal of corneal epithelium. Histological analysis showed no change in gross morphology of cornea and no evidence of apoptosis. In vivo treatment of rabbit eyes demonstrated initial thinning of corneal epithelium that recovered after seven days although with abnormal regularity of cells. Cellular outgrowth from corneal explant cultures after treatment further confirmed cell survival after treatment. Conclusions: This chemical cross-linking of corneal tissue has potential advantages over current therapeutic options including lower cytotoxicity to stromal cells than ultraviolet A treatment. Translational Relevance: The cross-linker has potential to become a treatment for keratoconus because it overcomes the need for procedures using specialized equipment and ensures accessibility to large populations.


Subject(s)
Keratoconus , Animals , Cornea , Cross-Linking Reagents , Humans , Keratoconus/drug therapy , Rabbits , Riboflavin , Swine , Ultraviolet Rays
5.
Indian J Ophthalmol ; 69(5): 1068-1072, 2021 05.
Article in English | MEDLINE | ID: mdl-33913834

ABSTRACT

Purpose: Earlier our group has demonstrated the drug reservoir function of the human amniotic membrane (HAM) using stable moxifloxacin and fortified cefazolin ophthalmic formulations and found it as a suitable tool to deliver drugs for an extended duration. The purpose of this study was to evaluate the extended-release kinetics of voriconazole from the impregnated human amniotic membrane (HAM) in vitro. Methods: HAM buttons were incubated with freshly prepared 1% topical ophthalmic formulation of voriconazole for 5 different exposure time to investigate the ideal exposure time for the extended-release of voriconazole from HAM. The drug release kinetics was studied in simulated tear fluid for 5 weeks and the amount of voriconazole released at different intervals was estimated using high-performance liquid chromatography (HPLC) with photodiode array (PDA) detector. Results: There was a marginal increase in drug entrapment efficiency with increased drug exposure time but neither the drug entrapment nor the drug release was found to be statistically significant (P ≥ 0.5). Voriconazole was detectable even at 5 weeks. Conclusion: A sustained release of voriconazole was achieved up to 5 weeks, when voriconazole was incubated with amniotic membrane for all the studied drug soaking times. Thus, voriconazole impregnated amniotic membrane can be considered for the sustained delivery for its in fungal keratitis.


Subject(s)
Eye Infections, Fungal , Pharmaceutical Preparations , Amnion , Antifungal Agents/therapeutic use , Eye Infections, Fungal/drug therapy , Humans , Moxifloxacin , Voriconazole
6.
Genomics ; 112(6): 4769-4776, 2020 11.
Article in English | MEDLINE | ID: mdl-32882326

ABSTRACT

The several virulence and drug-resistance mechanisms of Pseudomonas aeruginosa responsible for poor clinical outcomes in keratitis patients remain largely unknown. Here, we investigated the distribution of virulence factors and drug resistance by genes, mutations, efflux-pump systems of P. aeruginosa strains from keratitis patients with different clinical outcomes, included of whole-genome sequenced and annotated our five P. aeruginosa strains. Of the large number of virulence genes detected in all the genomes, MDR/XDR strains carry exoU and non-MDR strains carry exoS exotoxin of the type III secretion system, considered as main contributors of keratitis pathogenesis. However, several strain-specific virulence and resistance genes were detected in keratitis strains with poor outcome. Mainly, the flagellar genes fliC and fliD detected in the exoS carrying strains, reported to alter the host immune response, might impact the clinical outcome. This study may provide new insights into the genome of ocular strains and requires further functional studies.


Subject(s)
Keratitis/microbiology , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/genetics , Drug Resistance, Bacterial/genetics , Genome, Bacterial , Genomics , Humans , Microbial Sensitivity Tests , Virulence Factors/genetics
7.
Exp Eye Res ; 186: 107700, 2019 09.
Article in English | MEDLINE | ID: mdl-31233730

ABSTRACT

Corneal mycotic ulceration is predominantly due to Aspergillus and Fusarium solani infection in tropical countries. In this study, we examined the proteome profile of tear samples from A. flavus keratitis patients at various stages of infection. The proteome was profiled using 2D PAGE and the protein levels were quantified using 2D DIGE. Alpha-1-antitrypsin, apolipoprotein, haptoglobin, lactoferrin and albumin were up regulated while cystatin SA III precursor, lacrimal lipocalin precursor, lacritin precursor and Zinc alpha-2 glycoprotein (ZAG) were down regulated in tear fluid. In the case of ZAG all proteoforms were down regulated as the disease progressed from early to late stage of infection. Western blot analysis confirmed the results observed using DIGE. Further, there were no gender specific differences in the levels of ZAG expression in keratitis patient tear film. Published results show up regulation of ZAG in Fusarium keratitis patient tear indicating subtle changes in the early events of host response to these two fungal pathogens. We conclude that ZAG level could be used as an indicator of A. flavus or F. solani infection, even during the early stage of the disease.


Subject(s)
Aspergillosis , Aspergillus flavus , Eye Infections, Fungal , Keratitis , Proteome/metabolism , Seminal Plasma Proteins/metabolism , Tears/metabolism , Adolescent , Adult , Aged , Aspergillosis/metabolism , Aspergillosis/microbiology , Down-Regulation , Eye Infections, Fungal/metabolism , Eye Infections, Fungal/microbiology , Female , Humans , Keratitis/metabolism , Keratitis/microbiology , Male , Middle Aged , Young Adult , Zn-Alpha-2-Glycoprotein
8.
Indian J Ophthalmol ; 67(4): 472-475, 2019 04.
Article in English | MEDLINE | ID: mdl-30900576

ABSTRACT

Purpose: Our previous study demonstrated the drug reservoir function of human amniotic membrane (HAM) using stable moxifloxacin as a model drug. The purpose of the present study is to evaluate whether HAM can be used as a drug carrier for extended release of extemporaneous preparation of cefazolin. Methods: HAM Buttons (1 Control, 5 Test) were incubated in a freshly prepared (1 ml) sterile topical solution of cefazolin 5% (w/v) for 3 h and 24 h at two different temperatures. The groups were designated as follows: Group IA: Soaking duration 3 h at 4°C; Group IB: Soaking duration 3 h at room temperature; Group IIA: Soaking duration 24 h at 4°C; and Group IIB: Soaking duration 24 h at room temperature. The release kinetics of cefazolin from different groups of drug-laden HAM was studied for a period of 5 days. Samples were assayed for estimation of cefazolin content at different time intervals by High Performance Liquid Chromatography (HPLC) with Photodiode array (PDA) detector. Results: Three-hour cefazolin treatment with HAM at 4°C caused high drug entrapment (24%) compared to room temperature (11%; P < 0.005); however, the release kinetics was not significantly different between Group IA and IB as well as Group IIA and IIB up to the study period. Increase in drug treatment duration did not show increase in entrapment, but caused two-fold (IA Vs IIA) and 1.6-fold (IB Vs IIB) less drug entrapment at 4°C and room temperature, respectively. Conclusion: The results reveal that HAM may be a suitable drug carrier for extended delivery of fortified formulations without compromising stability.


Subject(s)
Amnion , Cefazolin/pharmacokinetics , Corneal Ulcer/drug therapy , Drug Carriers , Tears/chemistry , Anti-Bacterial Agents/pharmacokinetics , Cells, Cultured , Chromatography, High Pressure Liquid , Corneal Ulcer/metabolism , Corneal Ulcer/pathology , Drug Stability , Female , Humans , Ophthalmic Solutions
9.
Br J Ophthalmol ; 101(8): 1119-1123, 2017 08.
Article in English | MEDLINE | ID: mdl-28043985

ABSTRACT

BACKGROUND: Clinical outcomes in fungal keratitis vary between Fusarium and Aspergillus spp, therefore distinguishing between species using morphological features such as filament branching angles, sporulation along filaments (adventitious sporulation) or dichotomous branching may be useful. In this study, we assessed these three features within Heidelberg Retina Tomograph 3 in vivo confocal microscopy (IVCM) images from culture-positive Fusarium and Aspergillus spp keratitis participants. METHODS: Prospective observational cohort study in Aravind Eye Hospital (February 2011-February 2012). Eligibility criteria: age ≥18 years, stromal infiltrate ≥3 mm diameter, Fusarium or Aspergillus spp culture-positive. EXCLUSION CRITERIA: previous/current herpetic keratitis, visual acuity <6/60 in fellow eye, >80% corneal thinning. IVCM was performed and images analysed for branch angle, presence/absence of adventitious sporulation or dichotomous branching by a grader masked to the microbiological diagnosis. RESULTS: 98 participants were included (106 eligible, 8 excluded as no measurable branch angles); 68 were positive for Fusarium spp, 30 for Aspergillus spp. Mean branch angle for Fusarium spp was 59.7° (95% CI 57.7° to 61.8°), and for Aspergillus spp was 63.3° (95% CI 60.8° to 65.8°), p=0.07. No adventitious sporulation was detected in Fusarium spp ulcers. Dichotomous branching was detected in 11 ulcers (7 Aspergillus spp, 4 Fusarium spp). CONCLUSIONS: There was very little difference in the branching angle of Fusarium and Aspergillus spp. Adventitious sporulation was not detected and dichotomous branching was infrequently seen. Although IVCM remains a valuable tool to detect fungal filaments in fungal keratitis, it cannot be used to distinguish Fusarium from Aspergillus spp and culture remains essential to determine fungal species.


Subject(s)
Aspergillosis/diagnostic imaging , Eye Infections, Fungal/diagnostic imaging , Keratitis/diagnostic imaging , Adult , Aged , Aspergillus/isolation & purification , Corneal Ulcer/diagnostic imaging , Corneal Ulcer/microbiology , Female , Fusarium/isolation & purification , Humans , Keratitis/microbiology , Male , Microscopy, Confocal , Middle Aged , Young Adult
10.
Cornea ; 34(11): 1478-86, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26312622

ABSTRACT

PURPOSE: Using in vivo confocal microscopy, we established that unique hyperreflective structures in the anterior limbal stroma of healthy individuals represent the limbal stromal niche. The aim of this study was to characterize the limbal stromal microarchitecture in patients with limbal stem cell deficiency (LSCD). METHODS: After obtaining informed consent, 10 patients with LSCD and 3 with macular corneal dystrophy were recruited. In vivo confocal imaging of the limbus and cornea of the affected and normal eyes was performed using an HRT III laser scanning microscope, beyond the epithelium deep into the stroma. RESULTS: In the case of LSCD, the limbal epithelium was replaced by conjunctival epithelium. A large number of inflammatory and dendritic cells were identified along with blood vessels from the epithelium to deep stromal layers. The unique hyperreflective niche structures were replaced by homogenously bright fibrous structures in all eyes with total LSCD. In patients with partial LSCD, even the clinically defined normal limbus had fibrotic stroma. In a patient with focal LSCD, only the affected limbal stroma remained fibrotic, whereas the adjacent clinically normal limbus had the unique hyperreflective structures. Although the opaque corneal stroma appeared bright because of proteoglycan deposition, it was possible to identify the normal limbal epithelial and stromal architecture in macular corneal dystrophy. CONCLUSIONS: In the case of LSCD, the limbal stromal niche was replaced by bright fibrotic structures indicating persistence of damage several months after injury. Further studies are required to characterize the sequential events occurring in the anterior limbal stroma after injury using this noninvasive method.


Subject(s)
Corneal Dystrophies, Hereditary/pathology , Corneal Opacity/pathology , Corneal Stroma/pathology , Epithelium, Corneal/pathology , Limbus Corneae/pathology , Stem Cells/pathology , Adult , Cell Count , Corneal Stroma/cytology , Female , Humans , Limbus Corneae/cytology , Male , Microscopy, Confocal , Middle Aged , Stem Cell Transplantation
11.
Cornea ; 34(4): 464-70, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25742388

ABSTRACT

PURPOSE: To characterize the microarchitecture of anterior limbal stroma in healthy individuals using in vivo confocal microscopy (IVCM) and to correlate it with mesenchymal stem cells (MSCs), a component of the limbal niche. METHODS: The corneal side of the superior limbus was scanned in 30 eyes of 17 normal subjects beyond the basal epithelium, deep into the stroma using an HRT III laser scanning microscope. The IVCM findings were correlated with the immunohistochemical features of MSCs in the anterior limbal stroma. RESULTS: Clusters of hyperreflective structures were observed in the anterior limbal stroma, subjacent to the basal epithelium (depth, 50.2 ± 8.7 µm to 98 ± 12.8 µm), but not in the corneal stroma. The structures showed unique morphology compared with epithelial cells, keratocytes, neurons, and dendritic cells. In parallel, confocal analysis of immunostained sections showed clusters of cells, double positive for MSC-specific markers (CD90 and CD105) in the anterior limbal stroma at a depth of 55.3 ± 12.7 µm to 72 ± 37.6 µm. The organization and distribution of the MSC clusters locates them within the hyperreflective region in the anterior limbal stroma. CONCLUSIONS: The hyperreflective structures, demonstrated for the first time in the human anterior limbal stroma, probably represent an important component of the limbal niche. Our approach of in vivo imaging may pave the way for assessing the limbal stromal health.


Subject(s)
Corneal Stroma/cytology , Limbus Corneae/cytology , Adult , Biomarkers , Cell Count , Epithelium, Corneal/cytology , Female , Healthy Volunteers , Humans , Male , Mesenchymal Stem Cells/cytology , Microscopy, Confocal , Middle Aged , Young Adult
12.
J Proteomics ; 115: 23-35, 2015 Feb 06.
Article in English | MEDLINE | ID: mdl-25497218

ABSTRACT

Aspergillus flavus infects the human eye leading to keratitis. Extracellular proteins, the earliest proteins that come in contact with the host and virulence related exoproteins, were identified in the fungus isolated from infected cornea. Virulence of the corneal isolates was tested in the Galleria mellonella larvae model and those isolates showing higher virulence were taken for subsequent exoproteome analysis. High resolution two-dimensional electrophoresis and mass spectrometry were used to generate A. flavus exoproteome reference map as well as to profile most of the exoproteins. Analysis of the identified proteins clearly shows the major biological processes that they are involved in. Nearly 50% of the exoproteins possess catalytic activity and one of these, an alkaline serine protease (Alp1) is present in high abundance as well as multiple proteoforms. Many proteins in the A. flavus exoproteome have been shown to be virulence factors in other pathogens indicating the probable role for these proteins in the corneal infection as well. Interestingly, the majority of the exoproteins do not have secretory signal indicating that they are secreted through the non-classical pathway. Thus, this study provides a clue to the early strategies employed by the pathogen to establish an infection in an immunocompetent host. BIOLOGICAL SIGNIFICANCE: The outcome of a fungal infection in an immunocompetent human eye depends on the ability of the fungus to overcome the host defense and propagate itself. In this process, the earliest events with respect to the fungal proteins involved include the secretory proteins of the invading organism. As a first step towards understanding the role of the extracellular proteins, exoproteome profile of the fungal isolates was generated. The fungal isolates from cornea showed a distinct pattern of the exoproteome when compared to the saprophyte. Since corneal isolates also showed higher virulence in the insect larval model, presumably the proteins elaborated by the corneal isolates are virulence related. One of the abundant proteins is an alkaline serine protease and this protein exists as multiple proteoforms. This study reports the comprehensive profile of exoproteome and reveals proteins that are potential virulence factors.


Subject(s)
Alkaline Phosphatase/metabolism , Aspergillosis/metabolism , Aspergillus flavus , Corneal Diseases/metabolism , Proteome/metabolism , Animals , Aspergillus flavus/isolation & purification , Aspergillus flavus/metabolism , Aspergillus flavus/pathogenicity , Cornea/microbiology , Corneal Diseases/microbiology , Corneal Diseases/pathology , Disease Models, Animal , Fungal Proteins , Humans , Moths
13.
J Infect Dis ; 211(1): 130-4, 2015 Jan 01.
Article in English | MEDLINE | ID: mdl-25001461

ABSTRACT

Interleukin 17A (IL-17) production by peripheral blood neutrophils was examined in patients with fungal keratitis and in uninfected individuals in southern India, which has high levels of airborne Aspergillus and Fusarium conidia. Il17a gene expression and intracellular IL-17 were detected in all groups, although levels were significantly elevated in neutrophils from patients with keratitis. There were no significant differences in plasma IL-17 and IL-23 between patients with keratitis and uninfected individuals; however, combined data from all groups showed a correlation between the percentage IL-17 producing neutrophils and plasma IL-23, and between plasma IL-17 and IL-6 and IL-23.


Subject(s)
Eye Infections, Fungal/blood , Eye Infections, Fungal/microbiology , Interleukin-17/biosynthesis , Keratitis/blood , Keratitis/microbiology , Neutrophils/immunology , Adult , Aspergillosis/genetics , Aspergillosis/immunology , Aspergillosis/microbiology , Aspergillus/immunology , Case-Control Studies , Cohort Studies , Eye Infections, Fungal/immunology , Fusariosis/blood , Fusariosis/genetics , Fusariosis/immunology , Fusariosis/microbiology , Fusarium/immunology , Humans , India , Interleukin-17/blood , Interleukin-17/genetics , Interleukin-23/biosynthesis , Interleukin-23/blood , Interleukin-23/genetics , Interleukin-6/biosynthesis , Interleukin-6/blood , Interleukin-6/genetics , Interleukin-6/immunology , Keratitis/genetics , Keratitis/immunology , Middle Aged
14.
Microsc Res Tech ; 76(3): 242-8, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23280693

ABSTRACT

PURPOSE: Till date there is no exclusive marker for human corneal epithelial stem cells (CESCs). In this study, our strategy is to combine high expression of ABCG2, a putative SC marker with high N/C ratio to develop a specific method for identification of CESCs. METHODS: Limbal/corneal epithelial cells (LECs/CECs) were isolated from cadaver eyes by enzymatic treatment and the cytospin smears/cryosections were immunostained for ABCG2, p63, or connexin-43 (Cx-43) and counterstained with propidium iodide/DAPI. Analysis was carried out for (1) ABCG2 expression, N/C ratio, (2) p63, ABCG2, N/C ratio, and (3) ABCG2, Cx-43, N/C ratio using confocal/fluorescence microscopy. RESULTS: ABCG2 was highly expressed by cells in the basal and suprabasal layers of limbus. The SCs identified on the basis of our earlier method using high levels of p63 expression along with high (>0.7) N/C ratio were strongly positive for ABCG2 and negative for differentiation marker Cx-43. High expression of ABCG2 was also observed in cells with high p63 expression and low (<0.7) N/C ratio; however, they were positive for Cx-43. Combining high ABCG2 expression with large N/C ratio in fluorescence microscopy identified 5.3 ± 3.5% LECs as putative SCs and this was confirmed by confocal microscopic analysis. CONCLUSIONS: We demonstrate the importance of combining ABCG2 expression with N/C ratio for identification and quantification of human CESCs. This method will have application in evaluating the role of niche cells/factors in the maintenance of stemness.


Subject(s)
ATP-Binding Cassette Transporters/biosynthesis , Epithelium, Corneal/cytology , Gene Expression , Neoplasm Proteins/biosynthesis , Stem Cells/physiology , ATP Binding Cassette Transporter, Subfamily G, Member 2 , Humans , Microscopy, Confocal , Microscopy, Fluorescence
15.
J Infect Dis ; 204(6): 942-50, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-21828275

ABSTRACT

BACKGROUND: Filamentous fungi of the genera Aspergillus and Fusarium are major causes of corneal ulcers in the United States and in the developing world and result in significant visual impairment and blindness. METHODS: RNA was extracted from 110 patients with corneal ulcers in southern India within 1 week of infection with either Fusarium solani or Aspergillus flavus, and gene expression was determined by quantitative polymerase chain reaction. Posttransplant corneas from later stage disease (>2 weeks after infection) were also examined. RESULTS: Expression of Dectin-1, Toll-like receptor 2 (TLR2), TLR4, TLR9, and NOD-like receptor protein (NLRP)3 messenger RNA was elevated >1000-fold compared with uninfected donor corneas, whereas Dectin-2 was constitutively expressed in uninfected corneas. Furthermore, interleukin 1ß (IL-1ß) expression was elevated >1000-fold, whereas IL-1α expression was not increased. Expression of IL-8, IL-17, and tumor necrosis factor α was also elevated. CD3(+)and CD4(+) T cells were detected in infected posttransplant corneas. Expression of IL-17 and interferon γ was elevated but not that of IL-4. There were no significant differences in the host response between Aspergillus- and Fusarium-infected corneas at any time point. CONCLUSIONS: There is a common innate and adaptive immune response to these filamentous fungi, which includes the generation of T-helper 1 and T-helper 17 cells.


Subject(s)
Aspergillus flavus/immunology , Cornea/immunology , Fusarium/immunology , Gene Expression Profiling , Keratitis/immunology , Mycoses/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , India , Keratitis/microbiology , Male , Middle Aged , Mycoses/microbiology , Reverse Transcriptase Polymerase Chain Reaction , Th1 Cells/immunology , Th17 Cells/immunology , Young Adult
16.
Exp Eye Res ; 92(6): 454-63, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21396361

ABSTRACT

The proteomic profile of tear fluid is of fundamental interest in eye research. In this study we optimized the tear sample preparation method for two-dimensional (2D) analysis and determined the protein profile of tear fluid from healthy males and females. To find the most efficient method for tear sample preparation, four widely applied precipitation methods and ultrafiltration were compared. Of these, TCA precipitation & ultrafiltration resulted in efficient sample concentration and desalting. Use of a nonionic wetting agent, Tergitol NP7, in rehydration solution during isoelectric focusing improves protein separation in 2D gel electrophoresis considerably. Using this optimized method, tear protein profile was analyzed from healthy males and females. Of the thirty six tear proteins identified by LC-MS/MS, seven tear proteins were found to be significantly up regulated in the healthy female tear samples when compared to the male tear samples. These results indicate that the tear protein profile differs with respect to the sex. Mostly, the up regulated proteins are involved in the local immune defense; implying that there may be a sex difference in the ability to defend against infection at the anterior segment of the eyes of normal individuals.


Subject(s)
Eye Proteins/analysis , Proteome/analysis , Tears/chemistry , Electrophoresis, Gel, Two-Dimensional/methods , Fatty Alcohols/pharmacology , Female , Humans , Isoelectric Focusing , Male , Molecular Sequence Data , Peptide Fragments/analysis , Proteomics/methods , Sequence Analysis, Protein , Sex Factors , Tandem Mass Spectrometry
17.
Curr Eye Res ; 35(11): 953-60, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20958183

ABSTRACT

PURPOSE: The purpose of the present study was to evaluate the kinetics of single and multiple doses of topical, non-preserved voriconazole (VZ) in human eyes. METHODS: For single dose kinetics, 119 patients undergoing cataract surgery were divided into group I and group II and each group received a single drop (30 µl) of either 1% or 0.1% VZ formulation. Aqueous humor was collected at designated time intervals. For multidose kinetics, a single drop of 1% VZ was instilled 5 times either hourly or every 2 hr. The aqueous humor was tested for VZ at the 5th hr and 9th hr, respectively, after initial instillation. The stability and efficacy of the reconstituted VZ formulations were also evaluated after 30 days. RESULTS: Single dose ocular kinetics of 1% VZ resulted in a maximum mean aqueous concentration of 3.333 ± 1.61 µg/ml in 30 min whereas 0.1% showed a maximum mean aqueous concentration of 0.817 ±.36 µg/ml. In the multidose kinetic study, hourly and bi-hourly dosing resulted in mean aqueous concentrations of 7.47 ± 2.14 µg/ml and 4.69 ± 2.7 µg/ml, respectively. The reconstituted VZ formulations were stable at all studied temperatures, and their efficacy was maintained throughout the study period. CONCLUSION: The present study showed that the achieved mean concentration of VZ in both single dose and multi dose kinetic studies satisfactorily met the MIC(90) for almost all causative fungal organisms. The frequency of instillation may be designed for an "every 2 hr regimen" to maintain a therapeutic concentration for successful therapy.


Subject(s)
Antifungal Agents/administration & dosage , Antifungal Agents/pharmacokinetics , Aqueous Humor/metabolism , Pyrimidines/administration & dosage , Pyrimidines/pharmacokinetics , Triazoles/administration & dosage , Triazoles/pharmacokinetics , Administration, Topical , Aged , Aged, 80 and over , Area Under Curve , Cataract Extraction , Chromatography, High Pressure Liquid , Corneal Ulcer/prevention & control , Drug Stability , Eye Infections, Fungal/prevention & control , Female , Half-Life , Humans , Male , Middle Aged , Preservatives, Pharmaceutical/administration & dosage , Tandem Mass Spectrometry , Tissue Distribution , Voriconazole
18.
Arch Ophthalmol ; 126(5): 700-8, 2008 May.
Article in English | MEDLINE | ID: mdl-18474783

ABSTRACT

OBJECTIVE: To identify Solute Carrier family 4 (sodium borate cotransporter) member 11 (SLC4A11) gene mutations associated with autosomal recessive congenital hereditary endothelial dystrophy (CHED2). METHODS: DNA extraction from blood, polymerase chain reaction amplification, and direct sequencing of all the exons of the SLC4A11 gene were performed for 26 affected members of 20 unrelated families with CHED2. RESULTS: Of 10 mutations observed, 6 were novel, 1 of which involves a complete deletion of exon 6, identified for the first time, to our knowledge, in SLC4A11. The mutations cosegregated with the disease phenotype and were absent in 200 ethnically matched control chromosomes analyzed. CONCLUSIONS: This study increases the number of SLC4A11 gene mutations and confirms the role of this gene in causing CHED2. Clinical examination did not reveal any considerable variability in disease expressivity in patients carrying SLC4A11 mutations. Extensive linkage analysis may reveal the modifier genes involved in causing CHED2 in the SLC4A11 mutations unidentified in 9 families. CLINICAL RELEVANCE: In India, there is a high frequency of CHED2, possibly related to consanguineous marriages. Counseling could be provided to explain the drawbacks of consanguineous marriages to assist in reducing this devastating disorder.


Subject(s)
Anion Transport Proteins/genetics , Antiporters/genetics , Corneal Dystrophies, Hereditary/genetics , Endothelium, Corneal/pathology , Genes, Recessive/genetics , Mutation , Adolescent , Adult , Amino Acid Sequence , Child , Child, Preschool , Consanguinity , Corneal Dystrophies, Hereditary/ethnology , DNA Mutational Analysis , Exons/genetics , Female , Humans , India/epidemiology , Male , Molecular Sequence Data , Pedigree , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Promoter Regions, Genetic/genetics
19.
Mol Vis ; 14: 500-7, 2008 Mar 12.
Article in English | MEDLINE | ID: mdl-18385783

ABSTRACT

PURPOSE: Mycotic keratitis is a major cause of corneal blindness in India. A proper understanding of the pathogenesis may help in refining the existing treatment. The purpose of this study is to examine the total tear protein profile of fungal keratitis patients, which may have a bearing on pathogenesis and disease progression. METHODS: Tear samples were collected from culture positive fungal keratitis patients. Tears from the uninfected fellow eye and from other healthy individuals served as controls. Two-dimensional electrophoresis (2DE) was used for the separation of fractionated tear proteins, and selected protein spots, which showed differential expressions, were identified using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry. Wherever needed, tag sequencing of peptide fragments using post source decay (PSD) was done to confirm the identification. RESULTS: The glutaredoxin-related protein was expressed only in the tears of fungal keratitis patients. Six other normal tear proteins were present in both samples but with varied expression levels. Prolactin inducible protein and serum albumin precursor were upregulated in the infected samples. Cystatin S precursor, cystatin SN precursor, cystatin, and human tear lipocalin were downregulated in the infected samples. CONCLUSIONS: Tears can be used as a clinical source to study the proteomic responses in patients with fungal keratitis. The glutaredoxin-related protein is known to be produced by Aspergillus during oxidative stress conditions, and the presence of this protein in the tears of patients with mycotic keratitis indicates that this pathogen undergoes stress-related gene expression during infection.


Subject(s)
Aspergillosis , Eye Proteins/metabolism , Fusarium , Keratitis/metabolism , Keratitis/microbiology , Mycoses , Chromatography, Liquid , Electrophoresis, Gel, Two-Dimensional , Humans , Proteomics , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tandem Mass Spectrometry
20.
Am J Ophthalmol ; 144(1): 144-6, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17601443

ABSTRACT

PURPOSE: To analyze cases with posttraumatic lenticular abscess and study the etiology, clinical presentation, management, and outcome. DESIGN: Retrospective case series. METHODS: Seventeen eyes of 17 patients with traumatic lenticular abscesses were managed with extracapsular cataract extraction after aspirating the abscess. RESULTS: The mean age of the patients was 40.3 years, and males constituted 82%. The mean time to presentation after injury was 14.35 days (range, one to 60 days), and the patients had a mean follow-up of 125.94 days (range, 21 to 300 days). Culture of the lenticular abscess revealed bacterial growth in eight cases (47%) and fungi in four cases (23.5%). In five (29.4%) cases, culture was negative. Staphylococcus epidermidis grew in seven cases (41%). Thirteen eyes (77%) had best-corrected visual acuity better than 20/120. CONCLUSIONS: Surgical removal of the abscess, with systemic and local antimicrobial treatment is effective in cases of posttraumatic intralenticular abscess.


Subject(s)
Abscess/etiology , Eye Infections, Bacterial/etiology , Eye Infections, Fungal/etiology , Eye Injuries, Penetrating/complications , Lens Diseases/etiology , Lens, Crystalline/injuries , Abscess/therapy , Adult , Anti-Bacterial Agents/therapeutic use , Cataract Extraction , Combined Modality Therapy , Eye Infections, Bacterial/therapy , Eye Infections, Fungal/therapy , Eye Injuries, Penetrating/therapy , Female , Humans , Lens Diseases/therapy , Lens Implantation, Intraocular , Male , Retrospective Studies , Treatment Outcome
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