Ribosomal RNA of Nosema algerae and phylogenetic relationship to other microsporidia.

Microsporidia are intracellular parasites that are common in invertebrates. Taxonomic classification is mostly restricted to morphologic and physiologic data. Limited data are available about taxonomic classification using DNA-sequence data for analysis.

In vitro replication of Nosema algerae (Microsporidia), a parasite of anopheline mosquitoes, in human cells above 36 degrees C.

Microsporidia form a large and ubiquitous group of obligately intracellular parasitic eukaryotes, increasingly recognized as pathogens in humans. Transmission of invertebrate microsporidia to mammals has been considered impossible because temperature seemed to be a limiting factor for development. Nosema algerae, a microsporidian of anopheline mosquitoes, was cultured in human muscle fibroblasts at temperatures of 31 degrees C and 38 degrees C.

Relevant criteria for detecting microsporidia in stool specimens.

By using different staining techniques, 479 stool specimens from 212 diarrheic patients with AIDS were examined for microsporidian spores. Calcofluor fluorescence staining of 119 specimens revealed fluorescent ovoid structures of microsporidian size. Staining of these samples according to the method of Weber et al.

Morphologic changes in Nosema algerae (Microspora) during extrusion.

As a member of the phylum Microspora, Nosema algerae is a small obligate intracellular parasite. Its free invasive stage is a spore with a characteristic cellular organization, including an apically anchored polar tube that serves as a tool for the transmission of genetic material into the host cell. By detailed electron micrographic documentation of the spore ultrastructure we present the aspects related to the biologic process of spore extrusion.

[Fluorescence microscopy study of fluorescein in the posterior segment of the eye following local application of drugs].

After local application of gentamicin, dexamethasone and tropicamide to rat eyes, no effect on the permeability or the caliber of retinal vessels was observed, nor any diffusion of fluorescein from the choriocapillaris to the outer retinal layers. The qualitative assessment of fluorescence microscopic preparations (and photographic reproductions of them) is relatively unreliable and has led to confusion in the literature. The results presented here, which to some extent contradict earlier findings published in 1971, are discussed.

[Demonstration of ocular blood/tissue and blood/fluid barriers].

In addition to previous fluorescence-microscopic investigations on ocular barriers, quantitative fluorescence-photometric measurements on the eye tissues of albinotic rats were performed. The eyes were enucleated 5-30 min after intravenous injection, and tissue samples were compared with analogous eye tissues of untreated animals. The results were (I) different increases of measured data in the region of endothelium and stroma of the cornea, of vessels and stroma of the ciliary body and iris, of choroid and choriocapillaris, as well as of pigment epithelium and retina vessels; (II) no increase of the photometer values was observed in the epithelium of the cornea and in all other external and internal layers of the retina.

8-methoxypsoralen and long ultraviolet effects on the rat lens: experiments with high dosage.

The effect of systemic 8-methoxypsoralen (8-MOP; 100 mg/kg daily) and subsequent long ultraviolet irradiation (UVA; 300 mJ/cm2; peak: 365 nm) on albino and pigmented rat eyes was studied in a 3-dimensional experimental set-up. While 8-MOP and UVA did not cause any ocular pathology when administered alone, a combined application of the two factors caused reversible corneal opacities, and irreversible iris devascularisation and cataracts. The irreversible changes were seen only in the albinos and accompanied by a significant decrease in lens wet weight.

[Secondary fluorescence of intraocular vessels of the anterior segment of the rat eye after local drug application (author's transl)].

After local application of gentamycine, dexamethasone and tropicamide to rat eyes, no effect was observed on the permeability of the vascular wall of the iris and ciliary body compared with fluorescein-Na. Nor were there any changes in vessel caliber. The constriction of the dye column observed in corneal neovascularizations was not seen in the (normal) iris vessels and the vessels of the ciliary body.

[Behavior of fluorescein dye in the vascularized cornea of the animal eye after local application of certain drugs (author's transl)].

In pigmented rabbits we investigated the much-used drugs pilocarpine, atropine, and tropicamide (Mydriaticum, Roche) with regard to their possible influence on the permeability of newly formed corneal vessels. Sodium fluorescein was chosen as test substance. Corneal vessels were produced by introcorneal injection of 0.

[Differences in permeability for FITC-dextrane in cornea neovascularisation (author's transl)].

3 weeks after NaOH cauterization of rat corneas, the newly formed vessels were angiographically investigated by means of FITC dextran fractions. An angiographic picture similar to that of fluorescein Na was observed after intravenous administration of FD 3. A minimum diffusion of FD 40 could only be detected in the area of the distal terminal loops of the newly formed corneal vessels.

[Limited diffusion of dye between choroid and retina during animal experiments after injection of fluorescein and rhodamin (author's transl)].

For contributing to the question of an existence of a diffusion of the unbound part of the fluorescein between choroid and retina in fluorescein angiography, on pigmented rats, after intravenous injection of Fluorescein sodium and Rhodamine B respectively, comparing observations were effectuated. Rhodamine B in its unbound form showed a distinct diffusion between choroid and retina and coloured all retinal layers in the late phases whereas in the case of the Fluorescein sodium, only a poor diffusion was observable. The similar spectral bands of the primary and secondary fluorescences render difficult the observation of the behaviour of the fluorescein dye.

[Regression of corneal neovascularization by laser treatment? (author's transl)].

The corneal neovascularization produced by NaOH burns was examined in two groups of pigmented rabbits following laser treatment. The treatment was carried out with energy level 500 mW, spot diameter 200 micron, and exposure time 1 s throughout. In the first group, a single newly formed vessel was coagulated in each case.

[A rat holder for experimental fundus and anterior segment photography (author's transl)].

We conceived and manufactured a holder for rats. It is a useful little apparatus for some experiments on rats as well as for its fundus photography, angiographies included. The utility of our device is discussed and illustrated.

[Experimental fluorescein angiographic and microscopic investigations on laser treated rat eyes (author's transl)].

On fundi of pigmented rats, with Argon laser constantly 300 mW of power. 2 seconds exposure time and 50 microns spot diameter, coagulations have been performed. The eyes have been observed up till 3 months after the intervention, then angiographies were performed, and the following enucleated eyes have been examined with the fluorescence microscope.

[Occurrence of diffusions shown by fluorescence angiography of the laser coagulation in animals (author's transl)].

Laser treated rat fundi were observed angiographically and with the fluorescence microscope for 3 months. Angiographically diffusions have been observable up to about one week post laser, fluorescence microscopically, however, for the whole observation time of 3 months. From the 2nd week, these diffusions were produced mainly by neovascularizations which angiographically were not visible.

Observation of injected fluorescein diffusion after laser treatment of cat fundi. An experimental study with angiography and microscopy.

Argon laser coagulations with a power of 100 mW and 300 mW, exposure time 0.02 and 0.02 sec, and constant spot size of 100 microns were applied on normal cat fundi.

[Experimental fluorescence angiographic and microscopic investigations on laser treated animal eyes (author's transl)].

The effects of laser coagulation on rat fundi were studied angiographically and with the fluorescence microscope. The coagulations were performed using constantly 300 mW and 0.2 second exposure time and 50 microns spot diameter.