T6SS in plant pathogens: unique mechanisms in complex hosts.

Type VI secretion systems (T6SSs) are complex molecular machines that allow bacteria to deliver toxic effector proteins to neighboring bacterial and eukaryotic cells. Although initial work focused on the T6SS as a virulence mechanism of human pathogens, the field shifted to examine the use of T6SSs for interbacterial competition in various environments, including in the plant rhizosphere. Genes encoding the T6SS are estimated to be found in a quarter of all Gram-negative bacteria and are especially highly represented in , a group which includes the most important bacterial phytopathogens.

Genetic characterization and barcoding of taxa in the genus Wolffia Horkel ex Schleid. (Lemnaceae) as revealed by two plastidic markers and amplified fragment length polymorphism (AFLP).

The genus Wolffia of the duckweed family (Lemnaceae) contains the smallest flowering plants. Presently, 11 species are recognized and categorized mainly on the basis of morphology. Because of extreme reduction of structure of all species, molecular methods are especially required for barcoding and identification of species and clones of this genus.

Genetic structure of the genus Lemna L. (Lemnaceae) as revealed by amplified fragment length polymorphism.

Duckweeds (Lemnaceae) are extremely reduced in morphology, which made their taxonomy a challenge for a long time. The amplified fragment length polymorphism (AFLP) marker technique was applied to solve this problem. 84 clones of the genus Lemna were investigated representing all 13 accepted Lemna species.

A contribution to the histological and topographical anatomy of the aponeurosis of the levator palpebrae superioris and of the tarsal muscle in the normal lid and in blepharoptosis.

Eight normal upper lids were examinated histologically with special regard to the aponeurosis of the levator and of the tarsal muscle (Müller's). The aponeurosis originates from the levator muscle within the orbit (behind the septum orbitale) and inserts at the upper anterior surface of the tarsal plate. The tarsal muscle originates from the levator muscle and inserts at the upper tarsal border.

[Incomplete central vein occlusion. A clinicopathologic case report].

A 71-year-old patient died 4 weeks after the occurrence of incomplete occlusion of the central retinal vein. Histology of the two bulbi was compared with the photographic and fluorescenceangiographic findings of the fundus. Histologic evaluation showed that the occlusion had been caused by a thickening of the vein wall due to proliferation of fibrocytes and histiocytes just behind the lamina cribrosa.

[Ulcerative herpetic keratitis. Clinical and pathological findings and prognosis of the graft].

Between 1971 and 1982 33 corneae were excised for therapeutic keratoplasty because of ulcerative herpetic keratitis. The histologic findings and the clinical course enabled distinction of a nonreactive form with a rather good prognosis for keratoplasty (62% clear grafts) and an inflammatory form with bad prognosis (20% clear grafts) because of many herpetic recurrences. Perforating keratoplasty and first interventions in particular did better than lamellar keratoplasty or retransplantation.

[Juvenile nevoxanthogranuloma of the iris].

Juvenile Xanthogranuloma of the iris is a rare but benign disease of infants. The iris is swollen and of yellowish color, there are exsudates in the anterior chamber and occasionally spontaneous hyphema may occur. Secondary glaucoma with edema of the corneal epithelium and hydrophthalmus are often seen.

[Conjunctivitis lignosa].

A 57-year-old woman patient presented with a pseudo-membranous necrotizing conjunctivitis. The biopsy exhibited histological changes typical for conjunctivitis lignosa with definite vasculitis, vascular occlusions and vascular necrosis. The clinical course was typical for conjunctivitis lignosa.

[An epidemic of pseudomonas keratitis due to permanent-wear contact lenses (author's transl)].

In 1977 thirty-three patients (35 eyes) with permanent-wear contact lenses presented with keratitis in varying degrees of severity. Among the nine cases investigated bacteriologically (including some contact lenses) three showed no organisms, while six were found to have pseudomonas aeruginosa. The contact lenses all came from the same optician, where shortly beforehand the patients had had their lenses either replaced or checked.

[Dyskeratosis of the corneal epithelium (author's transl)].

Three patients presented an unilateral whitish cloudiness of the corneal epithelium which reduced the vision considerably. In two cases, radiotherapy was carried out previously (because of pterygium and because of teleangiectasia of the conjunctiva). In the eye of one patient, a superficial corneal lesion developed during general anesthesia.

[The role of bulb echography in the diagnosis of malignant melanoma of the choroid (author's transl)].

The combined A- and B-scan echography reliably separates intraocular melanoma from other intraocular lesion. This is showed by the analysis of 79 cases with clinically certain or possible melanoma during the last three years. In all 33 enucleated eyes the histology proved the echographic diagnosis of melanoma to be correct.

[A new iris double-forceps in the cryoextraction of cataract (author's transl)].

In the cryoextraction of a cataract associated with severe hypotension and narrow pupil, a new smooth iris double-forceps has been found useful for the grasping of the iris and the dilatation of the pupil. Thus, it will be possible to obtain a round pupil even in these rare cases.