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PubMed1991

[Effect of anti-glaucoma eyedrops on cell differentiation of the conjunctiva].

After local application of pilocarpine (minimum 1%), timolol (0.5%) or levobunolol (0.5%) to 6 patients, cell differentiation of the conjunctival epithelium was compared to that in 48 healthy persons. The least difference was found after pilocarpine application. The five ultrastructurally defined cell types were found to vary least when compared to the same cell types in normal subjects. The patients treated with timolol and levobunolol showed a reduction in secretory epithelial cells, especially within the conjunctiva bulbi, and a pronounced increase in cells with rough endoplasmatic reticulum. In addition to a loss of desmosomes and zonulae occludentes on the cell surface, a minimum 1-year application of the three antiglaucomatous medications leads to a reduction in the microvilli and microplicae and, particularly in patients treated with beta blockers, to intracellular changes, specifically increased vacuolization and dilation of the rough endoplasmatic reticulum. The latter may be attributable to the action of benzalkonium chloride (present as a preservative in all three eye drops studied) on the superficial epithelial cells. The cytotoxic action of the preservative may be intensified by the simultaneous application of beta blockers due to their destabilizing effect on the tear film.

Cell Differentiation↗
PubMed1991

Accumulation of Th-2-like helper T cells in the conjunctiva of patients with vernal conjunctivitis.

A total number of 132 T cell clones (TCC) were obtained by PHA-stimulation of single T cells from mononuclear cell suspensions of conjunctival flogistic infiltrates of three patients with vernal conjunctivitis (VC). The phenotype and functional properties of these TCC were compared with those of 122 TCC contemporarily established from PB mononuclear cell suspensions of the same patients, 120 TCC established from lymph nodes of three patients with nonspecific hyperplastic lymphoadenitis and 159 TCC established from thyroid lymphocyte infiltrates of three patients with Graves' disease. The great majority of conjunctival TCC displayed the CD4+ CD8- phenotype (CD4/CD8 ratios ranging from 6.1 to 7.0), whereas the mean CD4/CD8 ratios for control TCC ranged from 0.9 to 2.4. After stimulation with either PHA or PMA plus anti-CD3 mAb, conjunctival TCC differed from control TCC for their ability to produce cytokines. In particular, a large number of conjunctival TCC produced IL-4, but no, or limited amounts of, IFN-gamma, whereas no difference was observed between conjunctival and control TCC with regard to the production of IL-2. The failure of IFN-gamma production by conjunctival TCC was apparently not caused by delay or block in cytokine production, but actually reflected the lack of IFN-gamma transcription. Virtually all conjunctival TCC able to produce IL-4, but not IFN-gamma, as well as most of those producing both cytokines, provided helper function for IgE synthesis in allogeneic normal B cells. The accumulation in the conjunctiva of patients with vernal conjunctivitis of CD4+ T cells that, apart from the production of IL-2, resembles murine Th2 cells for their profile of cytokine production and helper function suggests a possible role for these cells in the pathogenesis of the disease.

Adult↗
PubMed1991

The effects of glaucoma medications on Tenon's capsule and conjunctiva in the rabbit.

Glaucoma filtering surgery fails most frequently due to fibrosis at the episcleral-conjunctival/Tenon's capsule interface. Sherwood et al have suggested that chronic topical antiglaucoma medications increase conjunctival inflammatory cells, which could increase the likelihood of fibrosis and subsequent bleb failure. In a pilot study in a rabbit model, we placed timolol, pilocarpine, and epinephrine, or a combination of all three, in one eye of 24 animals twice daily for 7 months. The fellow eye received distilled water. Microscopic examination revealed no statistically significant change in the number of acute or chronic inflammatory cells, fibroblasts, or goblet cells in the treated as compared with the control eyes. A longer duration of drug administration, or drug administration followed by surgical intervention, may be required to produce an effect on the conjunctiva and Tenon's capsule, if such an effect exists.

Administration, Topical↗
PubMedDate not supplied

Nucleolar organizer regions (NORs) in dysplastic and neoplastic epithelial lesions of the conjunctiva.

Using a silver staining technique (AgNOR technique), we have investigated the nucleolar organizer-associated proteins (NORs) in formalin-fixed paraffin embedded conjunctival specimens of 15 intraepithelial squamous carcinomas, 10 hyperplastic-dysplastic samples and 10 control epithelial fragments; the mean number of intranuclear black dots was determined for each case. A significant difference in the mean number of NORs was found when intraepithelial squamous carcinomas were compared with hyperplastic-dysplastic lesions (P less than 0.001); in addition, normal control conjunctiva and hyperplastic-dysplastic lesions were also discernible (P less than 0.05).

Adult↗
PubMedDate not supplied

Particle uptake by conjunctiva-associated lymphoid tissue (CALT) in turkeys.

Uptake of tracer particles was assessed in lower eyelid conjunctiva-associated lymphoid tissue (CALT) of 3-week-old turkeys. Tracer particle suspensions, including carbon, iron oxide, or three sizes of latex beads (0.81 micron, 1.7 microns, and 2.9 microns), were placed into the experimentally sealed conjunctival space. After 5, 15, or 30 minutes, eyelids were removed and CALT was examined by light microscopy. Uptake was confirmed for all tracers and occurred within the lymphoepithelium of CALT. The uptake of latex beads was not as frequent as for carbon and iron. Tracers were increasingly evident in lymphoepithelium and subepithelial macrophage clusters as contact time increased. These findings provide additional evidence that CALT is capable of antigen uptake and may play a role in paraocular and upper respiratory immunity in turkeys.

Animals↗
PubMedDate not supplied

Quantification of particle uptake by conjunctiva-associated lymphoid tissue (CALT) in chickens.

Tracer particle uptake by conjunctiva-associated lymphoid tissue (CALT) was quantified in the lower eyelids of 1-, 3-, 5-, and 7-week-old broiler chickens. CALT was measured histologically by computerized image analysis in all birds and in additional 1-day-old and 16-week-old chickens not subjected to uptake assessment. Suspensions of carbon or iron oxide were placed in contact with CALT for 5, 15, or 30 minutes (contact time). After eyelid removal, tracer uptake was scored by light microscopy, CALT was measured, and a mathematically derived uptake index was evaluated statistically. At each age examined, computer-generated measurements showed a significant increase in the proportion of CALT lymphoepithelium within proximal eyelids. Within the conjunctival sites evaluated, tracer uptake was significantly greater in lymphoepithelium than in non-lymphoepithelium at all ages and at all contact times. Uptake increased significantly between 3 and 5 weeks of age and between 5 and 15 minutes of tracer contact. Based on these uptake data for CALT in chickens, a minimal age-specific maturity is suggested that may influence function in mucosal immunity.

Animals↗
PubMed1978

[Mucoepidermoid carcinoma of the conjunctiva (author's transl)].

This is a report on a mucoepidermoid carcinoma in a 69 year old male, a rare occurence, originating clinically from the conjunctiva of the globe. The microscopic features, the pathogenesis and the histological differentiation are discussed.

Adenocarcinoma, Mucinous↗
PubMed1989

[Cytoenzymatic studies on the influence of soil dust on the cornea and conjunctiva of experimental animals].

The studies of the effect of the soil dust on the cornea and the conjunctiva of the experimental animals have been performed. The rats were divided into 3 experimental groups and 1 control group. The animals were given 3 different, selected at random, kinds of soil dust to the conjunctival sac 3 times daily for 7 days. The results show that the soil dust has the negative effect on the organ of sight. The cornea is particularly sensitive to the action of dust, which evidenced itself by the significant changes in the histochemical reactions.

Acid Phosphatase↗
PubMed1989

[The pathogen spectrum of the conjunctiva of inhabitants of refuse disposal sites in Cairo. I].

In Cairo's waste disposal sites conjunctivitis is frequently found resulting from the burning process of plastic, paper, etc.. Recurrent secondary contamination of the conjunctiva by pathogenic and non-pathogenic microorganisms often takes place; however, in certain germ species, the differentiation between pathogenic or non-pathogenic organisms within a damaged mucous membrane cannot be made. Furthermore, in this study, we have attempted to investigate germ reproduction during the application of PVP-eyedrops. However, our results cannot be conclusive because of the high environmental contamination, very low personal hygiene resulting from contaminated water and the constant exposure of samples to environmental contamination. Studies will be continued.

Air Microbiology↗
PubMed1988

Synergistic effects of LTB4 and LTD4 on leukocyte emigration into the guinea pig conjunctiva.

Leukotrienes (LT) B4 and D4, alone and in combination, were topically applied to the eyes of guinea pigs, and their effects on conjunctival leukocyte infiltration studied. LTD4 potentiated the neutrophil response to LTB4, even though no neutrophil emigration was evoked by LTD4 itself over a dose range of 10-1000 ng. LTB4 alone at the 1-ng and 10-ng doses failed to evoke any leukocyte emigration, but significant numbers of neutrophils were observed at these concentrations when LTD4 (1-1000 ng) was present. Although a dose-dependent increase in neutrophil infiltration was observed for the 100-ng and 1000-ng doses of LTB4, cell counts were substantially higher with these doses in the presence of LTD4. Eosinophil numbers increased in a dose-related manner in response to LTB4 and LTD4 alone, with a greater response to LTD4. The addition of either 10 ng or 100 ng of LTB4 to graded doses of LTD4 (10-1000 ng) caused increased eosinophil numbers, the lower dose of LTB4 potentiating the response to LTD4 and the higher LTB4 dose showing no significant effect. The effects on leukocyte infiltration that were evoked by the LT combinations could not be explained simply on the basis of an increase in vascular permeability. Bradykinin (BK), a potent conjunctival microvascular permeability factor that does not elicit any leukocyte infiltration, did not significantly potentiate LTB4-induced eosinophil or neutrophil emigration. The synergistic effects of LTs on leukocyte emigration are also difficult to ascribe to hyperemia (ie, increased blood volume in the conjunctiva), because both LTB4 and LTD4 caused only very modest increases in conjunctival blood content, and BK, which did not potentiate the leukocytic responses to LTB4, caused marked increases in tissue blood content. High-dose LT combinations caused eosinophils, but not neutrophils, to migrate into the conjunctival epithelium and fragment, resulting in overt tissue damage. These results further suggest a synergistic interaction between LTB4 and LTD4 that directly alters leukocyte function. The relevance of these observations to a number of disease and trauma states is discussed.

Animals↗
PubMed1989

[The value of studying the ocular conjunctiva in case-finding in prediabetic states].

Capillaroscopy, the only method available for the study of the microcirculation, without modifying its hydraulics, often provides a wealth of information in certain systemic diseases in which the microcirculatory involvement precedes clinical manifestations and of course, macrovascular complications. The prospective study of a healthy population is particularly demonstrative and the authors proposed scores on which diabetic microangiopathy could be suspected. The latter was confirmed by detailed laboratory investigations on one hand, and by the course of the disease on the other. For this reason, any subject at risk of diabetes should undergo at least one annual capillaroscopic examination of the ocular conjunctiva or if not, of the peri-ungual region. Furthermore, the study of microvessels in subjects with controlled and treated disease showed a regression of the anomalies which depended on proper control of diabetes, and this particularly nontraumatic test procedure which can be repeated and provides a wealth of information, can give a good reflection of proper therapeutic control, especially if it is performed by a trained and experienced investigator.

Capillaries↗
PubMed1979

Squamous metaplasia or epidermalization of the conjunctiva as an adverse reaction to topical medication.

Prolonged topical medication causes epidermalization of the conjunctiva in some patients. Loss of the normal conjunctival goblet cells, direct toxic effects on the corneal epithelium, and disturbance of lid function may combine to produce corneal changes which may be misinterpreted and treated with further potentially toxic compounds. Examples of conjunctival changes caused by miotic and non-miotic antiglaucoma therapy, mydriatics, preservatives, and antiviral compounds are presented.

Aged↗
PubMed1976

Immunotherapy with dinitrochlorobenzene (DNCB) for recurrent squamous cell tumor of conjunctiva.

Over the course of nine years a young man sustained repeated recurrences of a squamous papillary epithelial tumor of the conjunctiva and canaliculus. Treatment had included repeated surgical excisions, fulguration, cryotherapy, and localized applications of Thiotepa. When we examined him in 1972 he had a recurrent lesion measuring about 1 cm in diameter. Because of past failures with the above-noted therapeutic modalities, we decided to treat him with immunotherapy using the immunological adjuvant DNCB (dinitrochlorobenzene). We sensitized him systemically to DNCB by applying 2,000 microng of this agent to the skin of his forearm. A spontaneous "flare" reaction, indicative of delayed hypersensitivity, developed. Delayed hypersensitivity to DNCB was confirmed by in vitro testing of his lymphocytes for their ability to produce migration inhibitory factor (MIF) in response to DNCB. Subsequent localized application of DNCB to the conjunctival tumor resulted in rapid regression of the lesion and there has been no recurrence during a follow-up period of three years. We believe this is the first time a conjunctival tumor has been successfully treated with immunotherapy.

Adjuvants, Immunologic↗
PubMed1987

A seed tick infestation of the conjunctiva: Amblyomma americanum larva.

Ticks commonly infest humans but rarely bite the eyes. They are vectors of disease; therefore, rapid and complete removal is important. Their attachment can be so secure that removal is difficult or hazardous. We excised a larval form of Amblyomma americanum from a woodsman's conjunctiva.

Adult↗
PubMed1987

[Carcinoma in situ of the conjunctiva bulbi. Clinical and histopathologic findings].

The present paper communicates clinical and pathohistologic findings in a case of carcinoma in situ of the conjunctiva (Bowen's disease) with a five-year course. Initially, there are clinical similarities between Bowen's disease and Mooren's ulcer; the diagnosis can be established on the basis of the histologic findings. In this case the clinical picture at first resembled that of Mooren's ulcer. An epithelial dysplasia was confirmed histologically following perilimbal conjunctivectomy. A year later the dysplasia was found to have progressed and was treated by diathermy coagulation. At the check-up examination three months later the tumor had diminished in size. Four years later, however, it had redeveloped. As a rule, tumor excision is the treatment of choice. In the case described here it was first coagulated by diathermy because of its great extent, but this only brought the tumor to a temporary standstill.

Basement Membrane↗
PubMedDate not supplied

Graphite foreign body of the conjunctiva simulating melanoma.

A case of a growing vascular pigmented mass of the conjunctiva resembling a melanoma in a patient with a history of a pencil injury to the eye is presented. The lesion was surgically removed and histopathologically found to be a graphite foreign body granuloma. In the differential diagnosis of enlarging pigmented conjunctival lesions, graphite foreign body granuloma should be considered.

Adult↗
PubMed1985

[Condition of the microcirculatory bed of the bulbar conjunctiva in physiological and pathological pregnancies].

By means of biomicroscopic method the bulbar conjunctiva in 150 women (18-35 years of age) have been examined. Of them: 30 healthy women make the control group; the second group includes 60 healthy women at their first and second half of pregnancy; the third group includes 60 women with pregnancy developing against the background of noncomplicated insulin-dependent diabetus mellitus during their first and second half of pregnancy. In the healthy women there are not any significant changes in most of the parameters of the microcirculatory bed during the first half of their pregnancy, and in the second half of their pregnancy a great density of the blood vascular bed is determined. Diameters of all vessels in the hemomicrocirculatory bed are significantly increased, as compared to those in the control group. In the women suffering from diabetus mellitus, during the first half of pregnancy certain changes in the picture of the vascular network is observed, as well as an increased convolution. uneveness in distribution of blood vessels; in the second half of their pregnancy a pronounced deformity of the vacular network is observed, decreasing diameter of afferent vessels and an essential dilatation of postcapillaries and venules are registered. Certain signs of aggregation of blood formed elements is noted.

Adolescent↗
PubMed1979

[Functional and morphological basis for the nature of the microcirculatory bed reactions of the bulbar conjunctiva in experimental occlusion of the cranial mesenteric artery].

A complex analysis on changes occurring in conjunctival microcirculation and a number of indices of hemodynamics, hemorheology and metabolism at different time of experimental occlusion in the cranial mesenteric artery has demonstrated certain objective and many-sided correlations that prove a systemic character of biomicroscopical changes in the conjunctiva. The degree of changes in the conjunctival microcirculation depends on duration of occlusion. After a 3 hours' occlusion revascularization is accompanied by reversible general microcirculatory disorders that are registered in bulboconjunctiva. In a 6 and 12 hours' occlusion revascularization is characterized by increasing general changes in microcirculation.

Animals↗