Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022568 (keratitis)
 5,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Herpes simplex keratitis s a significant cause of blindness worldwide. Nitric oxide (NO) has been shown to play a role in non-specific defence mechanisms and cell signalling in bacterial and parasitic infections. We investigated if Herpes simplex virus (HSV) isolated from keratitis could induce NO production. Human corneal epithelial cells were infected with high (multiplicity of infection; MOI 0.4) and low (MOI 0.04) HSV-1 and HSV-2 concentrations. Culture supernatants were collected at 1 h, 4 h, 8 h, 12 h and 24 h postchallenge. Samples were prepared by removal of proteins by ultrafiltration. Production of NO was measured using nitrite and nitrate assays. Herpes simplex virus-1 downregulated the production of NO, while HSV-2 upregulated NO production. Downregulation of NO could be a survival strategy against the cytotoxic action of NO, to eliminate infected cells. Upregulation of NO production may be associated with the presence of glycoproteins on the viral coat, which have been shown to induce NO in other disease conditions. Further studies are required to confirm the role of NO in viral keratitis.
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PMID:The differential regulation of nitric oxide by Herpes simplex virus-1 and -2 in a corneal epithelial cell line. 1098 95

Herpetic keratitis and uveitis probably represent two of the most under- and misdiagnosed diseases affecting the anterior eye segment despite their being major causes of blindness in developed countries. Recurrences are pathognomonic of herpetic eye disease and are responsible for the high socioeconomic costs of this affection. In recent years, the application of molecular biological methods and the results of long-term clinical studies have afforded us new insights into the pathophysiology of herpetic eye disease and have advanced our perception of how best to manage it. This article summarizes our current understanding of the pathophysiology of herpetic eye disease and, in the light of this wisdom, discusses specific conditions (epithelial and geographic keratitis, ulcerating and non-ulcerative stromal keratitis, disciform keratitis/endotheleitis, uveitis and metaherpetic keratitis) as well as contemporary therapeutic and prophylactic strategies. The possible mechanistic basis of recurrence is also dealt with, as is the sociomedical relevance of the disease. In addition to providing a documentation of typical clinical pictures, the article also furnishes information respecting the course of the disease, its diagnosis and treatment.
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PMID:[Clinical manifestations of herpetic keratitis and uveitis]. 1121 82

We present a series of 1,540 corneal allografts studied since 1982. Corneal edema was the major lesion in 439 corneal specimens (28.4%). Keratitis was the largest group with 378 cases (24.5%), including 134 cases of corneal scarring (8.7%). There were 113 cases of herpes simplex virus keratitis (7.3%), mostly of the disciform stromal type, and 60 cases of non herpetic interstitial keratitis (3.9%), 44 of superficial keratitis (2.8%) and 10 of ulcerative keratitis (0.6%). Among the 17 other cases (1.1%), there were 3 of fungal keratitis, 2 syphilitic keratitis and one case of acanthamoebic keratitis. The third group was formed by corneal dystrophies with 376 cases (24.4%). There were 192 keratoconus (12.5%), 121 Fuchs' dystrophies (7.9%), 28 calcific band keratopathies (1.8%), 18 had corneal dystrophies with amyloid deposits and 16 did not. There were 169 regrafts (11%) and 135 traumatic lesions (8,8%). Among the 43 miscellaneous cases (2,8%), there were 22 cases with previous refractive eye surgery, one corneal myxoma, 5 cases of dysplasia, 5 pterigia, 3 sclerocornea, one fish-eye disease, one floppy eyelid syndrome and 5 unclassifiable cases. The mechanisms of these lesions are mainly related to an autoimmune disease in most cases of herpes keratitis. Some rare forms of corneal dystrophies contain amyloid deposits produced by an abnormal kerato-epithelin. Cases of graft failure are not particulary frequent, due to the avascularity of the cornea and its particular immune status.
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PMID:Histologic findings in a series of 1,540 corneal allografts. 1122 55

Famciclovir (FCV) is efficacious in the treatment of acute herpes zoster and recurrent genital infections but has not been used to treat ocular herpes simplex virus (HSV) infections. We evaluated the efficacy of orally administered FCV in treating HSV-1 epithelial keratitis and determined its effects on the establishment of latency and subsequent reactivation. Rabbits were inoculated with HSV-1 strain 17 syn+ and treated twice daily with increasing concentrations of FCV (60 to 500 mg/kg of body weight). This resulted in a significant, dose-dependent improvement in keratitis scores, as well as prolonged survival. Regardless of the dose of drug used, all groups exhibited the high rates of spontaneous and induced reactivation characteristic of 17syn+. The efficacy of 250 mg of FCV per kg was also compared to topical treatment with 1% trifluorothymidine (TFT). Although TFT treatment was more effective at reducing eye disease, FCV-treated rabbits had a better survival rate. Real-time quantitative PCR analysis of rabbit trigeminal ganglia (TG) demonstrated that FCV significantly reduced the HSV-1 copy number compared to that after treatment with TFT or the placebo but not in a dose-dependent manner. In summary, oral FCV treatment significantly reduces the severity of corneal lesions, reduces the number of HSV-1 genomes in the TG, improves survival, and therefore may be beneficial in reducing the morbidity of HSV keratitis in the clinic.
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PMID:Effect of famciclovir on herpes simplex virus type 1 corneal disease and establishment of latency in rabbits. 1140 21

BACKGROUND: Herpes simplex keratitis is a sight threatening ocular infection. A rapid and specific diagnosis is essential for the institution of specific antiviral therapy and to avoid complications that can arise from misdiagnosis and inappropriate treatment. Though a variety of techniques are available, isolation of Herpes simplex virus 1 (HSV-1) in culture provides the most reliable and specific method, and is considered as the gold standard in laboratory diagnosis of herpes simplex keratitis. We report a comparative study of the sensitivity of a 24 h-shell vial assay and conventional tube culture in the isolation of HSV-1 from corneal scrapings. METHODS: A total of 74 corneal scrapings obtained from 74 patients with a clinical suspicion of herpes simplex keratitis submitted for the isolation of HSV-1, were simultaneously inoculated into shell vial and tube cultures employing the vero cell line. Shell vial and tube cultures were terminated at 24 h and fifth day respectively. Isolation of HSV-1 was confirmed employing an indirect immunofluorescence assay. RESULTS: HSV-1 was isolated from 24/74 (32.4%) specimens employing both the methods. Sensitivity of both the techniques were found to be similar (20/24, 83.3%) (P = 1.0). CONCLUSION: A 24 h-shell vial assay is a rapid alternative technique in comparison to the time consuming conventional tube cultures for the isolation of HSV-1, especially from corneal scrapings for the laboratory diagnosis of herpes simplex keratitis.
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PMID:Comparison of the sensitivity of a 24 h-shell vial assay, and conventional tube culture, in the isolation of Herpes simplex virus - 1 from corneal scrapings. 1188 56

The author report about study results conducted in Russia during the recent 30 years and dedicated to the treatment of ocular pathologies caused by the virus of herpes simplex. Three high-efficiency directions took shape during the mentioned period: 1. Non-specific antiviral therapy based on the local and systemic administration of interferon inductors (poludan--complexes of poly A, poly U etc.) possessing an extensive spectrum of the antiviral and immune-modeling actions; 2. Antirecurrent therapy, including the application of herpetic vaccine against the virus of herpes simplex, types I and II, combined with immune-modeling agents. A focal allergic test with herpetic vaccine was offered, it made it possible, for the first time, a non-invasive diagnostics of intraocular herpes. 3. A system of sparing microsurgical methods adapted to the treatment of an active herpetic keratitis and its outcomes. A synergistic effect of interferon inductors and acyclovir was proven both experimentally and clinically; a method of local autocytokinotherapy (based on poludan), which turned out to be most effective in the treatment of severe lesions at the cornea and of intraocular herpes, was worked out. The authors believe that the methods and means offered for the treatment of ophthalmoherpes contribute, to a great extent, to handling with the ocular herpes viral infection.
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PMID:[Modern aspects in the treatment of ophthalmic herpes]. 1269 90

To determine the effect of roscovitine, a potent antiviral in tissue culture administered intramuscularly to rabbits or by eye drops to mice for the treatment of herpetic keratitis this study was commenced.New Zealand white rabbits infected with McKrae strain herpesvirus (HSV-1) were treated twice a day with 10mg Roscovitine or vehicle from day 3 to 7, or 1% trifluridine eye drops five times a day. Severity of keratitis was graded daily by a masked observer. ICR strain mice were randomized into 14 groups. Both corneas of the mice were scarified with a 25-gauge needle, and were inoculated with the KOS strain of HSV-1. Roscovitine was dissolved in Cremophor((R)) and tissue culture medium. Group 1A, 1B, 2A, and 2B mice were treated eight times daily with either 800 micro M Roscovitine or its vehicle. Trifluridine treated animals (groups 3A and 3B) received topical treatment five times daily. In groups 1A-3B, the treatment was begun two days prior to or two days after viral inoculation. Mice were examined on days 2, 3, 5, and 9 after infection. In rabbits, the severity of keratitis in animals treated with intramuscular roscovitine was not significantly different from that in vehicle-treated animals except on day 7 (p=0.0460). In mice, there was no significant difference between roscovitine and vehicle treatment at any time point studied. However, the trifluridine treated mice had significantly lower scores compared to the roscovitine or vehicle-treated mice. Although roscovitine dramatically suppresses viral replication in tissue culture studies, in vivo this drug failed to alter the course of HSV keratitis in rabbits or mice. Considering high cost of roscovitine and the poor efficacy in these experiments, we feel that roscovitine is not feasible antiviral agent for today.
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PMID:The effect of roscovitine on herpetic keratitis. 1274 50

Recent work suggests that herpes simplex virus (HSV) stromal keratitis in the mouse is caused by autoreactive T lymphocytes triggered by a 16 amino acid region of the HSV UL6 protein (aa299-314), Science 279, 1344-1347). In the present study we sought to determine whether genetic variation of this presumed autoreactive UL6 epitope is responsible for different pathogenic patterns of human HSV keratitis. To accomplish this, we sequenced the HSV UL6 gene from ocular isolates of 10 patients with necrotizing stromal keratitis, 7 patients with recurrent epithelial keratitis, and 8 patients with other forms of HSV keratitis. The sequences obtained predicted identical UL6(299-314) epitopes for all 25 viral isolates. Furthermore, the upstream sequence of all isolates was free of insertions, deletions, and stop codons. We conclude that different pathogenic patterns of human HSV keratitis occur independent of genetic variation of the HSV UL6 (299-314) epitope.
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PMID:Analysis of the herpes simplex virus type 1 UL6 gene in patients with stromal keratitis. 1278 27

To determine the distribution and activities of metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) during the course of experimental herpes simplex virus (HSV) type-1 keratitis, BALB/c mice were corneally infected with 10(5) plaque-forming units (PFU) of HSV-1 (KOS strain) and then observed for the clinical signs of keratitis. Corneas were harvested at days 0, 2, 7 and 14 post-infection (p.i.). MMP-2, MMP-9, MMP-8, TIMP-1 and TIMP-2 were detected by immunohistochemistry and the Western blot technique. The enzymatic activities were analyzed by zymography. Epithelial HSV keratitis was present at day 2 after corneal infection and healed by day 5 p.i. While the expression and activity of MMP-2, MMP-8 and MMP-9 increased in the corneas at day 2 p.i., it was reduced at day 7 p.i. TIMP-1 and -2 were expressed in the corneas before and seven days after infection. Necrotizing stromal keratitis with corneal ulceration and dense polymorphonuclear leukocyte (PMN) infiltration was present at day 14 p.i. This correlated with increased expression of MMP-2, MMP-8 and MMP-9 in the corneas. MMP-8, MMP-9 and MMP-2 staining was particularly intense in the proximity of the ulcers and in areas of PMN infiltration. At day 14 p.i., MMP-2, -8 and -9 activities were upregulated, and TIMP-2 was expressed. These data suggest that MMPs produced by resident corneal cells and PMNs may possibly play a role in early epithelial keratitis and in the ulcerative process in the late phase after corneal HSV-1 infection. The ratio of MMPs to TIMPs may be important for the course of necrotizing HSV keratitis. TIMPs might participate in the repair process.
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PMID:Matrix metalloproteinases (MMP-2 and 9) and tissue inhibitors of matrix metalloproteinases (TIMP-1 and 2) during the course of experimental necrotizing herpetic keratitis. 1287 54

Chronic corneal epithelial defects (CCEDs; indolent corneal ulcerations) are the most common refractory ulcerations in veterinary medicine and are diagnosed by their classic appearance. CCEDs are superficial ulcerations without stromal involvement and have a nonadherent epithelial border (lip). Fluorescein stain adheres to the exposed stroma and extends below the epithelial border, outlining the epithelial lip. CCEDs occur secondary to adnexal disease, keratoconjunctivitis sicca, exposure keratitis, neurotrophic keratitis, and primary corneal disease. In cats, herpes keratitis is associated with the development of CCEDs. Bacterial infections are not responsible for the refractory nature of CCEDs. Because of the refractory nature of CCEDs, treatment can be frustrating for both owner and veterinarian. Current treatment recommendations consist of identifying and treating the underlying cause and performing procedures that stimulate epithelialization and adhesion of the corneal epithelium. Initial treatment of CCEDs includes ulcer debridement and grid keratotomy. Superficial keratectomy is indicated in refractory cases.
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PMID:Diagnosis and management of chronic corneal epithelial defects (indolent corneal ulcerations). 1460 91


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