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Petechial hemorrhage of the conjunctiva and histological findings of the lung and pancreas in infantile asphyxia--evaluation of 85 cases.

Eighty-five cases of infantile asphyxia were examined in relation to the degree of conjunctivae petechial hemorrhages and histological and immunohistochemical findings of the lungs and the pancreas. In very young cases, even in the strangulation cases, conjunctivae petechial hemorrhages were unremarkable and sometimes absent. The lungs showed remarkable to moderate congestion, while the pancreas showed only slight to moderate edema and cell infiltrations. Many pancreata of cases of accidental and homicidal asphyxia had hyperplasia and nesidioblastosis of islet cells. In adult asphyxia cases, remarkable congestion has been the main finding in the lungs and the pancreas. This study shows many similarities between the findings in homicidal suffocation and in genuinely accidental suffocation, both in inspection and on histological examination. So, we here, stressed on the necessity of legal necropsy for various infantile asphyxia cases, in the speculation of the cause of death, in order to not only study infantile sudden death cause but also not to mis-diagnose genuine accidental asphyxia cases or homicidal cases using suffocation for Sudden Infant Death Syndrome (SIDS).

Asphyxia↗

Conjunctiva is an estrogen-sensitive epithelium.

BACKGROUND: To investigate whether the conjunctival epithelium shows cyclical maturation changes during the ovarian cycle and to study the cytological appearance of the conjunctiva in postmenopausal and pregnant women. PATIENTS: Fifteen menstruating women with ovulatory cycles, ten postmenopausal women, and twelve pregnant women in the second or the third trimester of their pregnancy. INTERVENTIONS: Conjunctival and vaginal smears were taken on a near-daily basis. MAIN OUTCOME MEASURES: The percentage of the parabasal, the intermediate and the superficial cells (Maturation Index) in each specimen was determined. RESULTS: In the conjunctival smears of the menstruating women cyclical maturation changes were noted. These changes were parallel to those of the vaginal smears, but to a minor degree. No cyclical changes were found in either the postmenopausal women or in the pregnant women, showing an extreme shift to the left in the Maturation Index. CONCLUSION: Conjunctiva appears to be a relatively estrogen-sensitive epithelium.

Adult↗

Active sodium and chloride transport across the isolated rabbit conjunctiva.

The bulbar-palpebral conjunctiva from albino rabbits was dissected as a cylinder and cut longitudinally to convert it to a flat epithelium that was mounted as a partition between Using-type chambers, exposing 0.38 cm2 of cross-sectional area. The tissue was bathed with a modified Tyrode's solution at 37 degrees C, pH 7.5. The tear-facing side (apical) was 14.6 +/- 1.5 mV negative relative to the basolateral side. Transepithelial resistance was 1.23 +/- 0.01 K omega.cm2 and the short-circuit current (Isc) was 14.4 +/- 1.3, microA/cm2. Sixty percent of the Isc could be accounted for by a Na(+)-dependent, bumetanide-inhibitable Cl- transport directed towards the apical side. The remainder of the Isc reflected a Na+ absorptive process at the apical surface that was amiloride resistant. Evidence was obtained that a likely contributor to this activity is an electrogenic Na(+)-glucose co-carrier. The Cl-dependent Isc was stimulated by forskolin and epinephrine. Permeabilization of the apical membrane with amphotericin B evinced a current carried by a basolateral Na+:K+ pump. An effect by heptanol suggested that part of the Isc traverse the epithelium via gap junctions. Our results imply that transport processes at the conjunctiva could influence the composition of the tear film.

Amiloride↗

Measurement of interleukin-4 and histamine in superficial cells of conjunctiva in patients with allergic conjunctivitis.

Interleukin 4 (IL-4) may play a role in the development of allergic disease. We questioned whether IL-4 related phenomenon occurred on the surface of the conjunctiva during allergic conjunctivitis. Ten patients with cedar pollen-allergic conjunctivitis and 10 patients with postsurgical conjunctivitis were enrolled in this study. Cells were collected by brush cytology from the upper palpebral conjunctiva. After the cells were cultured for 24 hours, the levels of IL-4, IgE, and histamine were measured in the supernatants. An ELISA was used for histamine and a highly sensitive sandwich ELISA for IL-4 and IgE. Conjunctival cells were also stained and fixed by May-Grunwalds stain solution. The number of superficial cells, especially lymphocytes, were compared in the two groups. The total number of cells collected by brush cytology did not differ in allergic vs., postsurgical conjunctivitis. Lymphocytes were similarly present in such specimens. The levels of IL-4 (p = 0.01) and histamine (p = 0.02) significantly increased in the specimens from patients with allergic conjunctivitis, although IgE was not detected in both groups. There was a correlation between the level of IL-4 and histamine (p = 0.0001). Conjunctival cells in allergic conjunctivitis produced a larger amount of IL-4 and histamine for cedar pollen compared to the postsurgical conjunctivitis. As with other allergic diseases, IL-4 may play a role similar to that of histamine in the development of allergic conjunctivitis.

Adolescent↗

Bacterial flora of the conjunctiva at birth.

In the largest study to date of bacterial flora in newborns, we cultured the conjunctivae of 100 infants within 15 minutes after vaginal delivery and before any antimicrobial agents had been applied to the eye. All cultures were intensively analyzed for anaerobic and aerobic bacteria. By far the largest group of bacteria isolated were microaerophilic, such as Lactobacillus species and diphtheroids, accounting for 46.8% of positive cultures and 62.3% of all bacteria isolated. The second largest group were true anaerobic bacteria, such as Bacteroides and Propionibacterium species. The smallest group were aerobic bacteria. This incidence of non-aerobic bacteria in the conjunctiva of newborns is the highest reported to date. Our finding should alert clinicians to consider non-aerobic, especially microaerophilic, bacteria in the differential diagnosis of ophthalmia neonatorum. The high rate of supposedly sterile cultures reported in other studies may be explained at least partially by improper isolation of non-aerobic bacteria.

Bacteria↗

[Seborrheic keratosis of conjunctiva: a case report].

CASE REPORT: Pigmented conjunctival lesions are a diagnostic challenge for the clinician. A 37-year-old man presented with a pigmented mass involving the conjunctiva of his right eye. Clinically, a diagnosis of malignant melanoma was made and a wide excision of the tumor was performed. The histopathologic diagnosis was seborrheic keratosis. DISCUSSION: Seborrheic keratosis is a benign lesion which occurs on the eyelids and face of middle-aged and elderly individuals. The occurrence of this lesion on the conjunctiva is rare, however there are 2 cases reported in the world literature. Seborrheic keratosis should be considered in the differential diagnosis of conjunctival pigmented lesions.

Adult↗

[Bacteria and resistance examination in bacterial conditions of the conjunctiva (author's transl)].

The optimal treatment of any inflammation within the area of conjunctiva, after recognition of pathogen and determination of resistance, is not always feasible in the daily practice of the ophthalmologist because usually immediate treatment is necessary. To test the (in vitro) efficacy of the medications available, determinations of pathogen and resistance were made in 100 conjunctival swabs taken from patients with inflammations of the conjunctiva and lacrimal duct. The relatively high incidence of resistance to penicillin, chloramphenicol and tetracycline should be the reason for using more effective substances such as gentamycine and rifamycin. The pathogens and resistance found at present are important criteria for the selection of appropriate chemotherapeutic agents.

Anti-Bacterial Agents↗

Quantification of MUC2 and MUC5AC transcripts in human conjunctiva.

PURPOSE: Transcripts of mucins 1, 4, and 5AC have been identified in human conjunctival tissue. Of these, only MUC5AC has been localized to goblet cells. MUC2 is a goblet cell mucin originally identified in the intestinal mucosa. The presence of MUC2 transcripts and levels of MUC2 and MUC5AC transcripts in normal human conjunctiva, as determined by quantitative polymerase chain reaction (PCR), is reported. METHODS: RNA from conjunctivae of six donors (3 men, 3 women, 44 to 69 years, all white) was isolated and subjected to competitive reverse transcription-PCR. Internal standards, which are dsDNA molecules with ends complementary to a given primer pair but containing nonhomologous central sequences, were prepared for each gene assayed. Titration of a constant amount of cDNA against serial dilutions of the internal standard allowed quantification of the template cDNA. MUC2 and MUC5AC levels were compared to levels of the "housekeeping" gene, beta2-microglobulin (beta2M). The identity of PCR products was confirmed by sequencing. RESULTS: In the six individual samples tested, beta2M mRNA is expressed, on average, at approximately 10(-20) moles per sample (1 microg RNA) or approximately 63.5x10(4) molecules. The mRNA encoding MUC5AC, a relatively abundant ocular mucin, exists at levels 10-fold lower than beta2M. In contrast to previous reports of MUC2 mRNA being absent at the ocular surface, these results show that MUC2 transcripts are present and expressed at levels 5900-fold lower than for MUC5AC. Apparently, MUC2 transcripts exist on the order of only approximately 100 to 1000 molecules/microg of RNA in the analyzed samples. CONCLUSIONS: MUC2 transcripts are present in human conjunctival tissue and their abundance is much lower than that of MUC5AC. This is the first application of competitive PCR to the quantitative analysis of mucin expression in human ocular tissue. The sensitivity of this method allows the detection of MUC2 transcripts that were not detected by Northern blot analysis or in situ hybridization in previous studies. It also makes possible the comparison of relative levels of expression for ocular mucins.

Adult↗

Electron microscopic studies on conjunctiva associated lymphoid tissue (CALT) in Angora goats.

The purpose of this study was to investigate the electron microscopic structure of conjunctiva associated lymphoid tissue (CALT) and to determine the uptake of macromolecules from follicle associated epithelium (FAE) of Angora goats. The sample tissues taken from lower and upper eyelids of ten 5-6 month-old healthy Angora goats were used in this study. The conjunctiva associated lymphoid tissue of Angora goats was formed by solitary or aggregate lymphoid follicle and follicle associated epithelium which cover these follicle. FAE was formed by flattened epithelial cells, lymphocytes, monocytes and polymorph nuclear leukocytes but no goblet cells. Ferritin particles were seen on the apical surface, in the invaginations, vesicles, vacuoles of flattened epithelial cells. It was concluded that these epithelial cells were specialized to uptake macromolecules.

Animals↗

Effect of latanoprost and timolol on the histopathology of the rabbit conjunctiva.

PURPOSE: Long-term medical treatment of glaucoma has an effect on the conjunctiva, possibly affecting the outcome of subsequent filtering surgery. The type and extent of these tissue changes caused by frequently used medications is important. An animal study using rabbits was performed to assess the tissue changes caused by timolol, latanoprost, and a combination of both substances. METHODS: Rabbits were treated with timolol, latanoprost, or a combination of these drugs for 18 months. Conjunctival specimens were examined by light microscopy, quantitative transmission electron microscopy, and immunohistochemistry with antibodies against matrix metalloproteinase (MMP)-3 and tissue inhibitors of metalloproteinase (TIMP)-2. RESULTS: By electron microscopy, the area of subepithelial collagen was significantly larger (P: < 0.03; Mann-Whitney test) in timolol-treated eyes (71.6%) than in control (52.7%) and latanoprost-treated eyes (57.7%). An increase of amorphous material was present in timolol-treated eyes (25.6% versus 7.6% in the controls) as well as a smaller area of empty spaces (2.5% versus 39.4% in control eyes). Latanoprost-treated eyes had no significant increase of empty spaces but showed a marked staining for MMP-3 in the conjunctiva. This staining was not present in control or timolol-treated eyes. Morphologically, degenerative changes of fibrocytes were seen in timolol-treated eyes only. CONCLUSIONS: A significant increase of subepithelial collagen density was present in timolol-treated eyes, whereas this finding was not apparent in latanoprost-treated eyes. Latanoprost-treated eyes showed an upregulation of MMP-3, which may be the reason for reduced extracellular matrix accumulation in such eyes. The morphologic feature of increased subepithelial collagen density and extracellular matrix changes may relate to failure of filtering blebs.

Animals↗

[Histological study of conjunctiva-associated lymphoid tissue in mice].

PURPOSE: To investigate conjunctiva-associated lymphoid tissue (CALT) in mouse conjunctiva. METHOD: We examined normal mice, ranging in age from 4 to 6 weeks, to investigate the presence of follicular tissue histologically. Next, we treated mice by topical instillation of ovalbumin and cholera toxin B, and then examined conjunctival follicles by immunohistological methods. RESULTS: Follicular tissue was present at the nictitating membrane. Both size and amount of follicular tissue was increased by the topical ovalbumin treatment. Immunohistological examination revealed CD4, CD8, and S-100 protein positive cells in follicular tissue. The epithelial layer, corresponding to follicular tissue, had intraepithelial pockets and CD4 positive cells in the pockets. CONCLUSION: It was concluded that the follicular tissue at the nictitating membrane is CALT in mice.

Animals↗

[Study of the nervous-vascular reactivity of the bulbar conjunctiva in patients with primary open-angle glaucoma with normalized intraocular pressure].

Clinical evaluation of adrenoreception was carried out in 96 patients with various clinical patterns of primary open-angle glaucoma with normalized intraocular pressure by changes in vascular reactivity in the bulbar conjunctiva capillaries in response to epinephrine and norepinephrine. Neuro-vascular reactions of the bulbar conjunctiva in response to norepinephrine and epinephrine were different in patients with different patterns of primary open-angle glaucoma with normalized intraocular pressure. A significant correlation between the rate of progress of optic disk glaucomatous atrophy and the parameters of ocular adrenoreceptor structures of the eye was detected.

Aged↗

[Corneal limbal stem cell autograft and conjunctiva transplantation for treatment of pterygium].

PURPOSE: To observe the therapeutic effects of corneal limbal stem cell autograft and conjunctiva transplantation for the treatment of pterygium. METHODS: Corneal limbal stem cell autograft and conjunctiva transplantation were performed on 38 cases (43 eyes) with newly developed or recurrent pterygium. The post-operative follow-up period ranged from 3 to 30 months (mean, 10 months). RESULTS: Of 38 cases (43 eyes), there were 34 cases (38 eyes) with stable epithelial healing and recovery of corneal transparency with no abnormal proliferation of pterygium-like tissue. 4 cases (5 eyes) were lost during the follow-up. CONCLUSION: To provide new stem cell source for injured limbus with limbal epithelial autograft transplantation is a reasonable therapeutic method for treatment of pterygium.

Adult↗

[The pterygium, Autologous conjunctiva-limbus transplantation as treatment].

Based on a new concept of the limbus as a junctional zone for separating the vascularized conjunctiva from the avascular cornea, this study presents conjunctival/limbal autograft transplantation for 22 cases of pterygium. The pterygia were primary in 17 eyes, cicatricial in 1 and recurrent in 4. In all cases a free transplant of the superotemperal limbus with an adjacent piece of thin conjunctiva was placed in the excision area. Postoperative follow-up ranged from 1 1/2 to 17 months, with a mean of 8.7 months. Only two pterygia recurred. In all other cases ideal anatomic reconstruction was achieved without any side effects. The authors believe that conjunctival/limbal transplantation is an encouraging technique for treating a pterygium surgically.

Conjunctiva↗

[Effect of 654-2 on the cerebral blood flow in patients with ischemic cerebrovascular disease by measurement of 133Xe rCBF and the microcirculation of bulbar conjunctiva].

Eighteen patients with cerebrovascular disorder were observed comparatively using 133Xe rCBF measurement and microcirculation test of bulbar conjunctiva before and after treatment with 654-2. Remarkable decreasing of blood flow in the brain and improving of bulbar conjunctiva microcirculation were found after treatment. We consider that the same drug caused the different change of blood flow in and out brain may due to the reaction of micrangium tissue construction, nerve regulation and different organ's micrangium to Ach. We recommend 133Xe as a objective measurement to estimate brain blood flow. The value of treatment of ischemic cerebrovascular disorder by 654-2 and raising microcirculation test as a objective measurement remains to discussed.

Adult↗

Calcitonin gene-related peptide immunoreactive nerve fibers in the rat conjunctiva.

Calcitonin gene-related peptide (CGRP) immunoreactive nerve fibers were studied in the rat conjunctiva by using indirect immunohistochemistry. Their origin was evaluated in a series of experiments where the animals were denervated by electrocoagulating the two first branches of the trigeminal nerve or by surgically extirpating the superior cervical ganglion. The CGRP-immunoreactive nerve fibers were seen mainly as thin varicose fibers in the epithelium and in the stroma. Many of the stromal fibers showed no apparent destination. However, CGRP-immunoreactive fibers were commonly found in association with stromal blood vessels, the smooth muscle of Müller, and the meibomian glands. Approximately 40% of the ganglion cells in the trigeminal ganglion were immunoreactive to CGRP. In the superior cervical ganglion, a few CGRP-immunoreactive fibers were seen although the ganglion cells were negative. After trigeminal denervation, all the epithelial and most of the stromal CGRP-immunoreactive nerve fibers disappeared. Sympathectomy had no effect on the presence of the CGRP-immunoreactive fibers. These observations indicate that most of the CGRP-immunoreactive nerve fibers in the rat conjunctiva are sensory nerves originating in the trigeminal ganglion. A few of the demonstrated fibers are, however, resistant to the sensory denervation and may be parasympathetic in their origin.

Animals↗

The effect of platelet-activating factor (PAF), histamine, and ethanol on vascular permeability of the guinea pig conjunctiva.

Increased vascular permeability, one of the characteristic features of immediate hypersensitivity (Type I), is mediated through a variety of compounds, including histamine and platelet-activating factor (PAF), a phospholipid inflammatory mediator. The effects on vascular permeability of histamine, PAF, and ethanol, the solvent for PAF, were compared in the guinea pig conjunctiva. Permeability at 30 min was investigated by evaluation of conjunctival edema and Evans blue extravasation (clinically estimated and colorimetrically measured). Doses of PAF from 1 to 10 nmol produced an increase in vascular permeability, with a peak effect at 10 nmol. Ethanol had no effect on vascular permeability below 40 X 10(3) nmol; above this concentration, however, permeability increased, reaching a maximum at 175 X 10(3) nmol. At low doses of PAF and ethanol, the effects were additive, whereas at 20-80 nmol of PAF with high concentrations of ethanol there was no additive effect of PAF, producing a decrease in the net effect of PAF. Histamine increased vascular permeability, with a minimum effect at 10 nmol and a maximum effect at 450 nmol. The slopes of the dose-response curves for all three compounds were linear and parallel, with statistically different potencies. The potencies for each compound were identical by all three methods of evaluation. Therefore, we conclude that PAF is a potential mediator in hypersensitivity reaction in the guinea pig conjunctiva, and that its effect is similar to but much more potent than that of histamine or ethanol. Since ethanol alone has a significant effect on vascular permeability, studies on PAF effects using control solutions without ethanol may be difficult to interpret.

Animals↗

[Conjunctival oxygen tension. Testing oxygen tension measurement of the conjunctiva].

A new apparatus which can measure oxygen tension and temperature in the conjunctiva was tested and compared with measurements of transcutaneous and arterial oxygen tension in eight volunteers in connection with normal oxygen tension, hypoxia and hyperoxia. In hypoxia, the conjunctival oxygen tension was found to be better correlated to and in better agreement with arterial oxygen tension than transcutaneous oxygen tension. The advantages with conjunctival oxygen measurements are continuous measurements in easily accessible and well vascularized tissue with the same arterial supply as the brain. In contrast to transcutaneous measurement, the new method does not require warming of the tissue as the conjunctiva is oxygen permeable.

Blood Gas Analysis↗