Long-Term Follow-Up of a Family with Retinal Dystrophy Caused by RPE65 Mutation

We present here the case histories of two siblings, a boy and a girl, with Leber’s congenital amaurosis (LCA). The diagnosis was based on non-recordable full-field electroretinogram (ffERG). The long-term ophthalmologic follow-up included kinetic perimetry (Goldmann), visual evoked potentials with flash stimulation, optical coherence tomography (OCT: B-scan images at the area of fovea), and multifocal ERG. The boy (sibling 1, born in 1986) was sent for electrophysiological examination at the age of four because he had nystagmus from birth. The diagnosis would be LCA based on non-recordable ffERG. Four years later, his visual acuity decreased rapidly due to vitreous opacification, caused by the autoimmune reaction of the retinal pigment epithelial cells. This was treated successfully with steroid injections, administered parabulbarly. Retinal autoimmune panel was not performed. Genetic testing became available only in 2019, and it revealed a RPE65 gene mutation: (NM_000329.2) c.{442G>A};{442G>A} (p.{Glu148Lys}; {Glu148Lys}). His sister (sibling 2, born in 1993) showed similar symptoms, caused by the same genetic mutation. Even though their parents were free of symptoms, it appeared that they were heterozygous carriers of the same mutation. Research of the family tree revealed a consanguineous marriage four generations before. Both siblings received successful gene therapy relatively late in their age: sibling 1 was 35 and sibling 2 was 28 years old, meaning that they were at an advanced stage of the disease. Nevertheless, follow-up examinations showed measurable improvements in their retinal function. The study shows that electrophysiological examinations, including flash-evoked responses, are useful in the objective evaluation of the progression in the central photoreceptor loss during the follow-up of LCA. The results also show that gene therapy can have beneficial effects even at an advanced stage of the disease

Characterization of Na+-K+-2Cl- Cotransporter Activity in Rabbit Lacrimal Gland Duct Cells

PURPOSE: We recently reported that isolated duct segments from rabbit lacrimal gland (LG) were able to secrete fluid in response to secretagogues, which were blocked completely by bumetanide. This suggests the functional involvement of Na+-K+-2Cl- cotransporter (NKCC1) in ductal fluid secretion. Therefore, the aim of this study was to investigate the activity profile of NKCC1 in isolated rabbit LG duct segments. METHODS: Interlobular ducts were isolated from fresh rabbit LG tissue. Microfluorometry with the ammonium (NH4+)-pulse technique was used to elicit pH changes in duct cells, and the rate of bumetanide-sensitive cytosolic acidification after addition of NH4+ was used to quantify the activity of NKCC1. RESULTS: While basal activity of NKCC1 was undetectable, low cytosolic chloride (Cl-) level and hyperosmotic challenge (390 mOsm) were able to increase the activity of NKCC1. Carbachol (100 muM) had no significant effect on NKCC1 activity. Elevation of cytosolic calcium (Ca2+) level with Ca2+-ionophore (A 23187, 1 muM) did not cause any alteration in the activity of the cotransporter while direct activation of protein kinase C (phorbol myristate acetate, 100 nM) increased its activity slightly but in a significant manner. Addition of either forskolin (10 muM), cell-permeable cAMP analogue (8-bromo cAMP, 100 muM) or vasoactive intestinal peptide (200 nM) resulted in a significant increase in the activity of NKCC1. CONCLUSIONS: These results highlight the functional involvement of NKCC1 in LG duct secretion. These findings may facilitate our understanding of LG function and may contribute to the development of targeted pharmacologic interventions in case of dry eye disease

Rhodes grass

<p>Subepithelial conjunctival naevus: anterior segment optical coherence tomography (AS-OCT) (A); histopathological appearance (B, hematoxylin-eosin, x10) and clinical appearance (C). Junctional conjunctival naevus: AS-OCT feature (D); result of histopathological examination (E, hematoxylin-eosin, x10); clinico-morphological appearance (F).</p

Comparison of anterior segment optical coherence tomography (AS-OCT), ultrasound biomicroscopy (UBM) and slit-lamp (SL) examinations in naevus margin visualization, in the detection of intralesional cysts and in posterior naevus shadowing in 21 conjunctival naevi (21 eyes).

<p>Comparison of anterior segment optical coherence tomography (AS-OCT), ultrasound biomicroscopy (UBM) and slit-lamp (SL) examinations in naevus margin visualization, in the detection of intralesional cysts and in posterior naevus shadowing in 21 conjunctival naevi (21 eyes).</p

Results of histological examination of the excised naevi (n = 24).

<p>Epithelial layer thickness above the naevus was measured on anterior segment optical coherence tomography images before surgical excision.</p

Localization of conjunctival naevi: Bulbar (A), caruncular (B), plical (C), intermarginal (D).

<p>Localization of conjunctival naevi: Bulbar (A), caruncular (B), plical (C), intermarginal (D).</p

Anterior segment optical coherence tomography (AS-OCT) features of conjunctival naevi (total number of naevi = 57).

<p>Anterior segment optical coherence tomography (AS-OCT) features of conjunctival naevi (total number of naevi = 57).</p

Clinical appearances of conjunctival naevi are extremely variable.

<p>Anterior segment pictures of amelanotic and cystic (A), moderately pigmented and cystic (B), small, strongly pigmented (C) and giant juvenile (D) conjunctival naevi.</p