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At least 19 recordsLinked to original sources
PubMed1978

Fluorescein iris angiography. II. Disturbances in iris circulation following strabismus operation on the various recti.

Iris circulation was investigated by fluorescein iris angiography in 33 human eyes before and after tenotomy of one or more recti for correction of strabismus. Tenotomy of one or both horizontal recti produced no appreciable circulatory disturbance in the iris, but tenotomy of superior or inferior rectus produced circulatory delay in superior temporal or inferior temporal sectors, respectively, of the iris. When tenotomies of a horizontal and one or two vertical recti were combined, the defect occurred in the region of the vertical rectus only. Blood supply of the nasal half of the iris was usually not disturbed by tenotomy of the vertical and/or medial rectus. The findings indicate that the blood supply of the iris is segmental and suggest that, in strabismus surgery, cutting the two vertical recti along with the lateral rectus may subject the eye to the risk of anterior segment ischemia. In the light of the present findings, physiological anatomy of the blood supply of the iris and role of the major arterial circle of the iris are discussed.

Adolescent↗
PubMed1978

Fluorescein angiography of the iris. A correlation of microangiopathy in the iris and retina.

Fluorescein angiography of the iris using filters that eliminated pseudofluorescence was performed. In 10 of 40 non-diabetic healthy eyes, a fine-grained leakage of dye occurred from capillaries of the pupillary margin (PML). In 87 of 94 diabetic eyes with or without retinopathy a PML was present. The vascular changes of the iris were compared with those of the retina as disclosed by fundus fluorescein angiography. In 14 of 18 eyes without retinopathy PML was observed. In 25 of 28 eyes with non-proliferative retinopathy there was a PML, 12 of those in addition showed extravasation to the iris stroma. All 48 eyes with proliferative retinopathy showed PML. In addition, 19 of these had extravasation to the iris stroma and 26 iris neovascularization. When iris neovascularization is present, larger fibrovascular proliferations are usually found in the vitreous space, often associated with recurrent vitreous haemorrhages or retinal detachment. Iris angiography yields valuable information on the vitreo-retinal diabetic sequelae and is useful for selection of such eyes for vitrectomy.

Adult↗
PubMed2024

Complete plastid genome of Iris orchioides and comparative analysis with 19 Iris plastomes.

Iris is a cosmopolitan genus comprising approximately 280 species distributed throughout the Northern Hemisphere. Although Iris is the most diverse group in the Iridaceae, the number of taxa is debatable owing to various taxonomic issues. Plastid genomes have been widely used for phylogenetic research in plants; however, only limited number of plastid DNA markers are available for phylogenetic study of the Iris. To understand the genomic features of plastids within the genus, including its structural and genetic variation, we newly sequenced and analyzed the complete plastid genome of I. orchioides and compared it with those of 19 other Iris taxa. Potential plastid markers for phylogenetic research were identified by computing the sequence divergence and phylogenetic informativeness. We then tested the utility of the markers with the phylogenies inferred from the markers and whole-plastome data. The average size of the plastid genome was 152,926 bp, and the overall genomic content and organization were nearly identical among the 20 Iris taxa, except for minor variations in the inverted repeats. We identified 10 highly informative regions (matK, ndhF, rpoC2, ycf1, ycf2, rps15-ycf, rpoB-trnC, petA-psbJ, ndhG-ndhI and psbK-trnQ) and inferred a phylogeny from each region individually, as well as from their concatenated data. Remarkably, the phylogeny reconstructed from the concatenated data comprising three selected regions (rpoC2, ycf1 and ycf2) exhibited the highest congruence with the phylogeny derived from the entire plastome dataset. The result suggests that this subset of data could serve as a viable alternative to the complete plastome data, especially for molecular diagnoses among closely related Iris taxa, and at a lower cost.

Iris Plant↗
PubMedDate not supplied

Serum and pancreatic immunoreactive insulin (IRI) and proinsulin-like component (PLC), serum IRI and PLC response to different stimuli in normal subjects and organic hyperinsulinism.

The serum levels of total immunoreactive insulin (IRI) and proinsulin-like component (PLC) in the fasting state and following the administration of insulin secretagogues in 5 patients with organic hyperinsulinism and age and sex matched normal subjects are reported. Diagnosis of organic hyperinsulinism could be established in all instances on the basis of the inappropriately high total serum IRI levels for the corresponding blood glucose values; such an abnormal relationship was not seen in normal subjects, and was further enhanced by insulin secretagogues. Unrestrained insulin secretion in organic hyperinsulinism was enhanced following the administration of glucose, tolbutamide, glucagon or amino acids; the last 2 stimuli are known to be ineffective in causing insulin secretion in the presence of hypoglycemia in normal subjects. Four patints had insulinomas and one probably had islet cell hyperplasia or abnormal function of islet cells. Chromatography of serum IRI to quantitate PLC is a useful adjunct to the diagnosis of organic hyperinsulinism as in the fasting state the proportion of PLC is always elevated, above the normal range of 5-22%. Following the administration of insulin secretagogues there was pronounced increase in total serum IRI in organic hyperinsulinism but the proportion of PLC generally decreased, suggesting thereby that mojor increase in IRI was due to release of stored granular IRI which is known to have a low proportion of PLC.

Adenoma, Islet Cell↗
PubMed1977

Solitary iris nevus associated with peripheral anterior synechiae and iris endothelialization.

Two middle-aged patients developed pigmented intrastromal iris nevi and an associated loss of the surrounding iris stromal markings suggestive of a surface iris membrane. Because of the fear of malignant melanoma with superficial growth, we excised the lesions. Histopathologic examination of the specimens revealed that the pigmented lesions were benign iris nevi and that the surrounding membrane was caused by endothelial cell growth onto the iris from peripheral anterior synechiae. These synechiae occurred anterior to Schwalbe's line in the same sector as the nevi and had been noted preoperatively at gonioscopic examination, but their diagnostic significance was not appreciated.

Adult↗
PubMedDate not supplied

Progressive essential iris atrophy, Chandler's syndrome, and the iris nevus (Cogan-Reese) syndrome: a spectrum of disease.

Progressive essential iris atrophy, Chandler's syndrome, and the iris nevus (Cogan-Reese) syndrome are considered to be variations of a single disease process, which is characterized by abnormalities of the cornea, anterior chamber angle, and iris. In each variation, the typical patient is a white woman with unilateral disease, negative family history, and an onset of symptoms in early to middle adulthood. Since the membrane theory of Campbell suggests that the disease is a fundamental abnormality of the corneal endothelium, rather than the iris, the term "iridocorneal endothelial syndrome," as proposed by Yanoff, may be an appropriate inclusive term for the spectrum of disease, although further study of the pathogenesis is needed. For each variation of the disease, corneal edema and secondary glucoma are both treated primarily by medical or surgical reduction of the intraocular pressure, although penetrating keratoplasty is occasionally required for cases with advanced corneal edema.

Adult↗
PubMed1977

Response to experimental implantation of autologous iris tissue and to iris injuries.

Autoimmune disease has been suspected in some cases of human uveitis. The initiating event has been thought to be injury and/or infection. To investigate the effect of injury on the uvea and on the immune apparatus rabbits and guinea pigs were subjected to various repeated iris insults, including implantation of autologous iris tissue into the anterior chamber of the contralateral eye. Of the procedures employed only iridectomy and insertion of iris produced some anterior chamber clouding, which was only slightly increased on repetition of the procedure; 76% of these animals failed to produce circulating CF antibodies. No local CF antibodies in the anterior chamber fluid nor increases in fluorescent antibodes in sections of the eyes could be detected. None of the animals tested developed skin hypersensitivity to homologous uveal antigen. None of the other traumatic procedures, which included repeated insertions of plastic into the anterior chamber, produced uveitis manifested clinically or by histological examination, circulating or local humoral antibodies, nor increases in fluorescent antibodies in the tissues of the eye. Introduction of antiuveal antibody into the anterior chamber also failed to produce uveitis. It can be concluded from these experiments that simple, repeated injury to the iris is not sufficient to elicit an autoimmune response under the conditions tested.

Animals↗
PubMed1976

Iris nodules in essential iris atrophy.

Seven cases are reported, believed to be the first in the literature, in which iris nodules are verified in the complete spectrum of essential iris atrophies. This feature appears late in the course of the disease as small yellow nodules that progressively increase in number and gradually become dark brown. The differential diagnosis of multiple iris nodules includes neurofibromatosis, melanomas, inflammatory nodules, and developmental anomalies such as iridocorneal dysgenesis.

Adult↗
PubMed1977

Behaviour of the iris vasculature in central retinal vein occlusion: a fluorescein angiographic study of the vascular response of the retina and the iris.

The findings in iris fluorescein angiograms of 48 eyes with central retinal vein occlusion (CRVO) were correlated with the predominant retinal vascular response. In 24 eyes with the non-ischaemic type of CRVO there were no or only minimal iris vessel changes, whereas in all 24 eyes with ischaemic type of CRVO there was iris vessel dilatation and leakage with or without neovascularisation. These findings support the hypothesis that hypoxic retina may be a cause of rubeosis iridis in CRVO.

Fluorescein Angiography↗
PubMed1976

[Proliferation of the cells of iris and pigment epithelium of the retina in the early periods after removal of the lens and iris in Spanish newts].

It has been shown by means of autoradiography that following the simultaneous removal of lens and retina in the eyes of adult ribbed newts (Pleurodeles waltlii) the proliferative processes related to the regeneration of retina, rather than lens, are most active at the early stages of eye restoration. During the lens regeneration in the absence of retina, the proliferation of the cells of pars iridica of the dorsal iris zone, a source of lens regeneration, is delayed, possibly due to the increase of the duration of mitotic cycle of these cells.

Animals↗
PubMed1975

Estimation of pancreatic IRI output rate and its relations to glucose tolerance in normal anasthetized dogs.

The pancreaticoduodenal and portal venous blood flows were recorded electromagnetically in anaesthetized dogs. Blood glucose and IRI were measured in the arterial, portal, and peripheral venous as well as in the intestinal venous blood. By a mathematical model the actual net IRI output of the whole pancreas was estimated. Under basal conditions it is 10.2 +/- 2.4 mU/min (n = 30; 26 kg mean body wt.). After i.v. glucose injection, IRI output is rapidly enhanced. The biphasic nature of this reaction was unequivocally demonstrated by consideration of the ratio IRI output : blood glucose. Pancreaticoduodenal blood flow increases transiently in relation to the increased blood glucose concentration. The IRI secretion rate is well correlated with the blood glucose concentration and to the amounts of glucose or of blood reaching the whole pancreas. It is also correlated with the portal IRI Concentration. The overall peripheral venous or arterial IRI concentrations are correlated with the IRI secretion rate, but not in all individual experiments. The different phases of IRI output (basal rate, stimulated output 1-10 min and 10-60 min) show no influence on each other, nor are they correlated with the peripheral IRI concentration area. Basal IRI output is negatively correlated with the glucose assimilation constants. These constants or the peripheral BG areas, however, are independent of the stimulated IRI output rate. However, both the assimilation constants and the peripheral BG areas are related to the peripheral IRI concentration areas. Hepatic uptake of insulin and dynamics of pancreatic blood flow seem to contribute considerably to the estimated correlation pattern.

Animals↗
PubMed1976

Iris pigmentation and atropine mydriasis.

The experiments were designed to study the well-known pigment-dependent mydriatic effect of atropine in the eye. In vitro, relative to the accumulation of 3H-atropine by the nonpigmented rabbit iris, the pigmented iris accumulated high amounts of the drug. A nonpigmented tissue, stomch fundus strip, obtained from either albino or nonalbino animals, accumulated relatively low amounts of 3H-atropine. On repeated washings, the accumulated drug from the nonpigmented tissues was rapidly lost, T 1/2 of 14 minutes, while that accumulated by the pigmented iris was retained much longer. Although in vitro aqueous humor from serum-atropinesterase positive rabbits rapidly degraded atropine, extracts from irides of the same type of rabbit gave a single peak radioactivity, with Rf identical to the authentic atropine sulfate. The accumulation of 3H-atropine by pigmented human iris or pigment epithelium was similar to that observed for the pigmented rabbit iris. pA2 values of atropine from nonpigmented iris and from fundus strips varied between 8.58 and 8.88 with slope values close to 1. The pA2 value of atropine in pigmented iris was 8.82; at higher concentrations, atropine was less effective compared to the nonpigmented iris. In the pigmented iris, the lesser effectiveness of the drug at high concentration could be explained on the basis of accumulation of the drug by the pigment cell and its constituents. Thus, the free concentration of the drug in the vicinity of the muscarinic receptor will fall. The lesser concentration will give weaker muscarinic blockade in the pigmented iris. On repeated washing, the atropine blockade of the nonpigmented iris could be easily washed out while that in the pigmented iris was retained. In vivo, the relative T 1/2 for the duration of atropine mydriasis in rabbits were: albino atropinesterase-positive, 3.8 hours; nonalbino atropinesterase-positive, 12.4 hours; albino atropinesterase-negative is greater than or equal to 96 hours. Only the latter T 1/2 for the duration of atropine mydriasis is quite clear. The small magnitude of the mydriatic effect in humans is explained by the loss of free drug to the pigment cells and their constituents. The longer duration of mydriatic effect in the heavily pigmented eye is explained on the basis of slow release of the accumulated drug onto the muscarinic receptor.

Animals↗
PubMed1975

Iris nevus (Cogan-Reese) syndrome. A cause of unilateral glaucoma.

Fourteen patients (ten women, four men) with iris nevus (Cogan-Reese) syndrome, all having unilateral glaucoma, were studied clinically. Many had corneal edema, and all had changes in the iris consisting of one or more of the following: iris whorls or nodules or both, atrophy of iris stroma, heterochromia (the darker iris usually involved), or ectropion uveae. All had peripheral anterior synechias. Material for histological study was available from ten patients and showed a nonmalignant diffuse nevus of the anterior surface of the iris. An overgrowth of endothelium and Descemet membrane extending onto the iris surface may be a characteristic part of the process. Patients tended to be women in middle age. Conservative treatment avoiding enucleation is advised. Whenever a patient with suspected iris nevus syndrome or essential iris atrophy is subjected to glaucoma surgery, a biopsy specimen of the iris should be obtained for histological study.

Adolescent↗