摘要:

After recovery from primary herpes simplex virus (HSV) infection of the eye in rabbits, recurrent shedding of virus in the external eye can be produced by the local application of 6-hydroxydopamine (6-HD) and epinephrine. Surgical sympathectomy did not prevent shedding of HSV with 6-HD/epinephrine so the source of the virus in the outer eye induced by adrenergic stimulation is not just the superior cervical ganglia (SCG). Chemical sympathectomy with 6-HD prior to HSV infection of the cornea led to decreased viral replication in the SCG during acute infection but did not interfere with uptake of the virus and latent or low grade infection of the ganglion. Shedding of virus in the outer eye induced by 6-HD/epinephrine was reduced by treatment with the beta-adrenergic blocker, timoloi. These experiments strongly suggest that recurrent HSV shedding in the eye induced by catecholamines is due in part to effects on the peripheral (i.e. post synaptic) cells. While the peripheral neurons are the source of virus, it is possible that not all HSV detected in the external eye is due to release of preformed virus from nerve endings.

ISSN:0271-3683    

DOI:10.3109/02713688609015095

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

This paper reports the existence of midget bipolar cells on the chick retina, as determined by the staining methods of Golgi-Stensaas and Golgi-Colonnier. We date the appearance of these cell types at days 13 (HH-39) and 14 (HH-40) of incubation and describe them morphologically throughout their development until the time of hatching, at which time the cells show an adult structure. As an adjunct to this work we classify the midget bipolar cells into four groups.

ISSN:0271-3683    

DOI:10.3109/02713688609015096

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

The present study examined the anti-herpetic effect of the glycoprotein inhibitors, hydroxynorvaline and 2-deoxyglucose, alone and in combination with trifluridine on murine ocular herpes. Following ocular inoculation with a large dose of HSV-1 RE strain (106pfu), ICR mice were treated during the acute infection with different therapeutic regimens, and their efficacy was evaluated by ocular virus titers, clinical grading of blepharo-conjunctivitis and histological evaluation of stromal keratitis and iridocyclitis. The results following a large dose HSV-1 inoculum demonstrated that trifluridine was the best single therapeutic agent. Hydroxynorvaline and 2-deoxyglucose had no effect at all. Combination therapy of the glycoprotein inhibitors with trifluridine was no better than trifluridine alone. The mouse HSV-1 keratitis model proved to be an effective, economical alternative to the rabbit model for the evaluation of new antiviral agents.

ISSN:0271-3683    

DOI:10.3109/02713688609015097

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

This sd˚udy demonsd˚rad˚es in a rabbid˚model of eplred˚Inal membrane formad˚ion d˚had˚red˚lnal-assoclad˚ed ODC acd˚ivid˚y increases during d˚his pad˚hological process. These changes In red˚inal-associad˚ed ODC acd˚ivid˚y mosd˚likely occur In relad˚ionship d˚o d˚he proliterad˚ive lesion Id˚self, since d˚he red˚ina consisd˚s primarily of non-pro) Iferad˚ive d˚issues. Furd˚her knowledge of Ind˚raocular polyamlne med˚abolism during eplred˚inal membrane formad˚ion which can resuld˚In red˚inal ded˚achmend˚may lead d˚o d˚he developmend˚of an effecd˚ive pharmacological d˚read˚mend˚.

ISSN:0271-3683    

DOI:10.3109/02713688609015098

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

Collagen, fibronectin and laminin are important components of the extracellular matrix of the human cornea. We used the immunofluorescence technique with polyclonal antibodies directed against these proteins and to bullous pemphigoid antigen (BPA), in order to study their distribution in human corneas from 8 weeks of gestation to term and in adult corneas.Immunoreactivity was observed with antibodies to type I collagen in the limbus and the corneal stroma at 8 weeks of gestation. At 11 weeks of gestation it was found in epithelial basement membrane (EBM) and Descemet's membrane (DM) and continued thus throughout fetal and adult life. Type II collagen was not detected in fetal or adult cornea. Type III collagen was detected during 8–20th weeks of gestation in the EBM, DM and stroma. After 27th weeks of gestation, type III collagen could no longer be detected in the central cornea. Type IV collagen was detected in the EBM as early as 8 weeks of gestation and remained positive throughout fetal and adult life. Descemet's membrane was negative for type IV collagen at 8 weeks of gestation and became positive thereafter.Immunostaining for fibronectin in DM was negative at 8 weeks of gestation, followed by patchy staining of corneal stroma and EBM up to the age of 37 weeks of gestation. Staining in the EBM was negative or variable up to 70 years of age, and then became positive again in a 77 year old individual. Staining for LN was positive in the EBM after 8 weeks of gestation. Staining was negative in DM at that age, but became positive after 9 weeks of gestation. Staining for BPA was negative at 8–9 weeks of gestation, then gradually became positive.

ISSN:0271-3683    

DOI:10.3109/02713688609015099

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

The isoelectric point distribution of G-3-P DK and TPI from human lenses was examined as a function of age and cataract formation. Both enzymes exhibited progressive heterogeneity with age ard a shift towards an acidic charge. Little qualitative differences in the pI profiles of G-3-P DH and TPI were found to distinguish mixed cataracts from age comparable normal lenses. While the most alkaline form of G-3-P DH required less HasO4−for optimal activity, or other kinetic property, i.e. Km substrate, cofactor and inhibitors distinguished any of the charge forms of G-3-P DH. All meta-or isozyme forms of TPI had the same Km substrate in the forward and reverse reaction direction. The most acidic forms of G-3-P DH and TPI were less stable to increased temperatures than their more alkaline counterparts suggesting a decreased stability.1. Metazymes are variants of enzymes that are not primarily genetically coded but occur as secondary enzyme modifications (1).

ISSN:0271-3683    

DOI:10.3109/02713688609015100

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

The water soluble (WS), urea soluble (US) and urea insoluble (UI) fractions from individual human lenses 1.8 to 65 years of age were isolated from concentric fiber layers. In lenses younger than 19 years, a uniform distribution in the amount of WS, US and UI fractions was found throughout the entire lens. These fractions represent 83, 11.5 and 5.5%, respectively, of the lens dry weight. This compositin was observed with the cortical fibers of all lenses examined up to the 65-year old. In the nuclear fiber layers, the proportion of US protein gradually increases in the third to fourth decade of lens growth and appears to have reached a maximum representing 22–24% of the nuclear fiber mass in 50-year and older lenses. A large increase in the amount of the UI fraction to 30% of the fiber mass was observed in lenses between the 5th and 6th decade of lens growth. The change from the cortical to nuclear composition occurs in a narrow region of the lens which becomes more peripheral with aging.The cortical WS fractions were characterized by well defined polyacrylamide gel bands in sodium dodecyl sulfate (SDS). Those of the nuclear fibers were broadened, especially in the 27/29 and 16/18 kilodalton (KD) region. The disappearance of the 20/22 KD bands in the inner cortical and nuclear fibers cannot be accounted for by the small increase in protein insolubilization in these regions of lenses 40 years or younger.

ISSN:0271-3683    

DOI:10.3109/02713688609015101

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

Most pathologies of the outer retina include physiological and morphological changes in the pigment epithelium. The question of pigment epithelial involvement in retinal light damage caused by low intensities of light is still unresolved. In the present study, we investigated the effects of low intensity cyclic light on pigme nt epithelial function in albino rats. The functioning of the pigment epithelium was assessed electrophysiologically from d.c. recordings of ERG c-waves and sodium azide induced changes in the resting potential. Responses obtained from albino rats raised under low intensity cyclic light [0.63 ft cd, 12:12 L:] were compared to those obtained from albino rats raised under minimal light exposure conditions (dark-reared]and pigmented rats housed under low intensity cyclic light. We report, for the first time, that albino rats raised from birth under low intensity cyclic light possess c-waves. Their responses were comparable in amplitude and latency to those recorded from pigmented rats housed under similar conditions. but were significantly smaller than those recorded from dark-reared albino rats. The reduction in the amplitudes of the c-waves recorded from cyclic light-reared albino rats was probably not due to retinal light damage. Comparisons of the ampI itudes and latencies of ERG b-waves recorded from cyclic light-reared and dark-reared albino rats did not suggest that the retinas of the cyclic light-reared albino rats had been damaged by light. Light microscopic examination of these retinas also provided no evidence for light damage. The transient, positive potential changes recorded f rom cyclic light-reared albino rats in response to bolus injections of sodium azide were significantly smaller than those recorded from either dark-reared albino rats or pigmented rats housed under low intensity cyclic light. The results of these experiments suggest that the pigment epithelium of albino rats is functionally altered by extremely low intensities of cyclic light.

ISSN:0271-3683    

DOI:10.3109/02713688609015102

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

After corneas of mice had been totally denuded of their epithelium by the application of n-heptanol, the new epithelium which grew over the corneas was studied by electron microscopy at intervals up to 7 months. The purpose was to compare the basal attachment of the new cells, derived from conjunctiva, with that of true corneal epithelial cells growing on the same type of substratum, and studied previously.Goblet cells appeared after 2 weeks amid the squamous type of epithelial cells which had resurfaced the cornea in about 1 week. Goblet cells increased up to at least 6 weeks, but had decreased by 3 months. They persisted, however, for the entire 7 months of the study. Goblet cells had only a small area of contact with the basal lamina, and they had few desmosomes or hemidesmosomes.Basal cells of the squamous type had complex features of their basal attachment quite different from those of normal or repairing corneal epithelial cells studied previously. Flat cytoplasmic extensions of squamous cells underlay most of the goblet cell basal pole which therefore had only a small area on the basal lamina. Numerous filaments inserted into desmosomes and hemidesmosomes of squamous cells, and prominent bundles of these filaments lay just above the basal plasma membrane. They were orientated parallel to the radial axis of the cornea. Closely spaced corrugations of the basal plasma membrane were also orientated in this axis, as well as rows of hemidesmosomes. Even after a period of 7 months, the morphological features of conjunctival cells did not come to resemble those of normal corneal epithelium. The radial arrangement of fibers, hemidesmosome rows, and corrugations is interpreted as a reflection of the continued centripetal migration of the epithelium.

ISSN:0271-3683    

DOI:10.3109/02713688609015103

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor

摘要:

The low activity level of lenticular Y-glutamylcysteine synthetase appears to be an evolutionary phenomenon restricted to higher primates. Rapid reduction with age of the activity of both enzymes (γ-glutamylcysteine synthetase and glutathione synthetase) required for glutathione synthesis in the human lens was demonstrated in an earlier study.The activities ofγ-glutamylcysteine synthetase and giutathione synthetase, the two enzymes responsible for glutathione synthesis, were determined in 39 lenses from the rhesus monkey (Macaca mulatta) as a function of age. The ages ranged from 137 day old fetuses to a 34 year old monkey. Glutathione synthetase activity decreased 8-fold (units/g lens), 7-fold (units/mg soluble protein) and 2-fold (units/lens) over the age span studied.γ-Glutamylcysteine synthetase activity decreased 3-fold (units/g lens), 4-fold (units/mg soluble protein) and less than 2-fold (units/lens) over the same age span. A small increase inγ-glutamylcysteine synthetase activity (units/lens) from embryonic lenses to birth and one year of age was followed in later years by a decrease in activity. In adults, the overall ratio of glutathione synthetase activity toγ-glutamylcysteine synthetase activity was 42:1 as compared to 77:1 for the human and 2:1 to 4:1 for common domestic species. The aging study data indicate that the rhesus monkey lenticular glutathione synthesis system appears to be a good model for the human lens enzymic system.

ISSN:0271-3683    

DOI:10.3109/02713688609015104

出版商:Taylor&Francis    

年代:1986

数据来源: Taylor