[Scoring system for chronic open glaucoma]. / Evaluation du glaucome chronique à angle ouvert par un score de gradation: analyse préliminaire.

PURPOSE: The aim of this study was to evaluate a scoring system for chronic open-angle glaucoma. We devised an empirical scoring system grading severity of the disease and correlated this with treatment. MATERIAL: and methods: Ninety patients were evaluated on 11 parameters: 1) Family history of glaucoma: blindness (2), yes (1) no (1); 2) Age: infantile (4), juvenile (4); 3) Race: Caucasian (0), Asian (1), Afro-Caribbean (2); 4) Myopia: 0-6 diopters (1), 6-12 diopters (2),>12 diopters (3); 5) Pigment dispersion or pseudoexfoliation (1); 6) Intraocular pressure without treatment:>30 mmHg (4); 25-30 mmHg (3), 20-25 mmHg (2); 7) Corneal central thickness:<500 micro m (3),>500 micro m (0); 8) Optic disc appearance: suspect (1), pathological (4); 9) Visual field defect: early (1), moderate (3), advanced (5); 10) Vascular risk factors: yes (1), no (0); 11) Loss of eyesight in one eye due to glaucoma (4). Scoring values were 2-34. We correlated this score with patient treatment: medical or surgical, number of glaucoma medications. RESULTS: Patients were divided into three groups: group 1 (36 patients), score 0-8; group 2 (24 patients), score 9-13; group 3 (30 patients), score above 13. Distribution between patients treated with medicine (mean number of medications) and patients with filtering surgery was: group 1, medical treatment with 1.63+/-0.73 medications, surgery 4/36; group 2, medical treatment with 2.00+/-0.7 medications, surgery 17/24 and group 3, medical treatment with 2.12+/-0.67 medications, surgery 27/30. In group 1, 88% of the patients did not have filtering surgery, but 90% of the patients in group 3 had filtering surgery. CONCLUSION: This scoring system seems to be an easy and practical tool to evaluate chronic open-angle glaucoma, which could also be used to evaluate target pressure. Other studies are necessary to validate this scoring system.

Solution structure of a zinc substituted eukaryotic rubredoxin from the cryptomonad alga Guillardia theta.

The rubredoxin from the cryptomonad Guillardia theta is one of the first examples of a rubredoxin encoded in a eukaryotic organism. The structure of a soluble zinc-substituted 70-residue G. theta rubredoxin lacking the membrane anchor and the thylakoid targeting sequence was determined by multidimensional heteronuclear NMR, representing the first three-dimensional (3D) structure of a eukaryotic rubredoxin. For the structure calculation a strategy was applied in which information about hydrogen bonds was directly inferred from a long-range HNCO experiment, and the dynamics of the protein was deduced from heteronuclear nuclear Overhauser effect data and exchange rates of the amide protons. The structure is well defined, exhibiting average root-mean-square deviations of 0.21 A for the backbone heavy atoms and 0.67 A for all heavy atoms of residues 7-56, and an increased flexibility toward the termini. The structure of this core fold is almost identical to that of prokaryotic rubredoxins. There are, however, significant differences with respect to the charge distribution at the protein surface, suggesting that G. theta rubredoxin exerts a different physiological function compared to the structurally characterized prokaryotic rubredoxins. The amino-terminal residues containing the putative signal peptidase recognition/cleavage site show an increased flexibility compared to the core fold, but still adopt a defined 3D orientation, which is mainly stabilized by nonlocal interactions to residues of the carboxy-terminal region. This orientation might reflect the structural elements and charge pattern necessary for correct signal peptidase recognition of the G. theta rubredoxin precursor.

Eukaryotically encoded and chloroplast-located rubredoxin is associated with photosystem II.

We analyzed a eukaryotically encoded rubredoxin from the cryptomonad Guillardia theta and identified additional domains at the N- and C-termini in comparison to known prokaryotic paralogous molecules. The cryptophytic N-terminal extension was shown to be a transit peptide for intracellular targeting of the protein to the plastid, whereas a C-terminal domain represents a membrane anchor. Rubredoxin was identified in all tested phototrophic eukaryotes. Presumably facilitated by its C-terminal extension, nucleomorph-encoded rubredoxin (nmRub) is associated with the thylakoid membrane. Association with photosystem II (PSII) was demonstrated by co-localization of nmRub and PSII membrane particles and PSII core complexes and confirmed by comparative electron paramagnetic resonance measurements. The midpoint potential of nmRub was determined as +125 mV, which is the highest redox potential of all known rubredoxins. Therefore, nmRub provides a striking example of the ability of the protein environment to tune the redox potentials of metal sites, allowing for evolutionary adaption in specific electron transport systems, as for example that coupled to the PSII pathway.

Identification and characterization of a eukaryotically encoded rubredoxin in a cryptomonad alga.

We have identified an open reading frame with homology to prokaryotic rubredoxins (rds) on a nucleomorph chromosome of the cryptomonad alga Guillardia theta. cDNA analysis let us propose that the rd preprotein has an NH(2)-terminal extension that functions as a transit peptide for import into the plastid. Compared to rds found in non-photosynthetic prokaryotes or found in bacteria that exhibit an anoxigenic photosynthesis apparatus, nucleomorph rd has a COOH-terminal extension, which shows high homology exclusively to the COOH-termini of cyanobacterial rds as well as to a hypothetical rd in the Arabidopsis genome. This extension can be divided into a putative membrane anchor and a stretch of about 20 amino acids with unknown function linking the common rd fold to this anchor. Overexpression of nucleomorph rd in Escherichia coli using a T7 RNA polymerase/promotor system resulted in a mixture of iron-containing holorubredoxin and zinc-substituted protein. Preliminary spectroscopic studies of the iron form of nucleomorph rd suggest the existence of a native rd-type iron site. One-dimensional nuclear magnetic resonance spectroscopy of recombinant Zn-rd suggests the presence of a stable tertiary fold similar to that of other rd structures determined previously.

Transport of proteins into cryptomonads complex plastids.

Complex plastids, found in many alga groups, are surrounded by three or four membranes. Therefore, proteins of the complex plastids, which are encoded in the cell nucleus, must cross three or four membranes during transport to the plastid. To study this process we have developed a method for isolating transport-competent two membrane-bound plastids derived from the complex plastids of the cryptophyte Guillardia theta. This in vitro protein import system provides the first non-heterologous system for studying the import of proteins into four-membrane complex plastids. We use our import system as well as canine microsomes to demonstrate in the case of cryptomonads how nuclear proteins pass the first nucleomorph-encoded proteins the third and fourth membrane and discuss the potential mechanisms for protein transport across the second membrane.

Chloroplast protein and centrosomal genes, a tRNA intron, and odd telomeres in an unusually compact eukaryotic genome, the cryptomonad nucleomorph.

Cells of several major algal groups are evolutionary chimeras of two radically different eukaryotic cells. Most of these "cells within cells" lost the nucleus of the former algal endosymbiont. But after hundreds of millions of years cryptomonads still retain the nucleus of their former red algal endosymbiont as a tiny relict organelle, the nucleomorph, which has three minute linear chromosomes, but their function and the nature of their ends have been unclear. We report extensive cryptomonad nucleomorph sequences (68.5 kb), from one end of each of the three chromosomes of Guillardia theta. Telomeres of the nucleomorph chromosomes differ dramatically from those of other eukaryotes, being repeats of the 23-mer sequence (AG)(7)AAG(6)A, not a typical hexamer (commonly TTAGGG). The subterminal regions comprising the rRNA cistrons and one protein-coding gene are exactly repeated at all three chromosome ends. Gene density (one per 0.8 kb) is the highest for any cellular genome. None of the 38 protein-coding genes has spliceosomal introns, in marked contrast to the chlorarachniophyte nucleomorph. Most identified nucleomorph genes are for gene expression or protein degradation; histone, tubulin, and putatively centrosomal ranbpm genes are probably important for chromosome segregation. No genes for primary or secondary metabolism have been found. Two of the three tRNA genes have introns, one in a hitherto undescribed location. Intergenic regions are exceptionally short; three genes transcribed by two different RNA polymerases overlap their neighbors. The reported sequences encode two essential chloroplast proteins, FtsZ and rubredoxin, thus explaining why cryptomonad nucleomorphs persist.

Ancient gene duplication and differential gene flow in plastid lineages: the GroEL/Cpn60 example.

Cryptomonads, small biflagellate algae, contain four different genomes. In addition to the nucleus, mitochondrion, and chloroplast is a fourth DNA-containing organelle the nucleomorph. Nucleomorphs result from the successive reduction of the nucleus of an engulfed phototrophic eukaryotic endosymbiont by a secondary eukaryotic host cell. By sequencing the chloroplast genome and the nucleomorph chromosomes, we identified a groEL homologue in the genome of the chloroplast and a related cpn60 in one of the nucleomorph chromosomes. The nucleomorph-encoded Cpn60 and the chloroplast-encoded GroEL correspond in each case to one of the two divergent GroEL homologues in the cyanobacterium Synechocystis sp. PCC6803. The coexistence of divergent groEL/cpn60 genes in different genomes in one cell offers insights into gene transfer from evolving chloroplasts to cell nuclei and convergent gene evolution in chlorophyll a/b versus chlorophyll a/c/phycobilin eukaryotic lineages.

[Pigmented basal cell carcinoma of the eyelid. Apropos of a clinical case]. / Carcinome basocellulaire tatoué de la paupière. A propos d'une observation anatomo-clinique.

A clinico-pathologic case of a 83-year-old female patient with a deeply pigmented inferior lid tumor is reported. The histopathological study of the tumor demonstrated a pigmented basal cell carcinoma. Numerous different tumors may affect the eyelids, melanocytic or not in nature. True melanomas are infrequent compared with the numerous other pigmented tumors, which always need a histological analysis.

[Palpebral form of mixed tumor of the lacrimal gland. Apropos of a case]. / Forme palpébrale d'une tumeur mixte de la glande lacrymale. A propos d'une observation.

The clinico-pathological findings in a 45-year-old male patient with a lacrimal gland tumor are reported. This tumor had a spontaneous course of about nine years before it was resected. The clinical presentation was unusual as the tumor appeared as a nodular well-circumscribed swelling of the lateral part of the left superior eyelid. Imaging techniques did not reveal any involvement of the orbital part of the lacrimal gland. However a wide supero-lateral approach was chosen to achieve monobloc resection. Histopathology showed the typical features of an encapsulated pleomorphic adenoma, with no suspicious cytologic changes. Complete resection had a total curative effect for the patient. A wide lateral approach seems to be mandatory for tumors of the lacrimal gland to avoid partial resection and local recurrences.