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Due to the major role of the sun in heating the earth's surface, the atmospheric planetary boundary layer over land is inherently marked by a diurnal cycle. The afternoon transition, the period of the day that connects the daytime dry convective boundary layer to the night-time stable boundary layer, still has a number of unanswered scientific questions. This phase of the diurnal cycle is challenging from both modelling and observational perspectives: it is transitory, most of the forcings are small or null and the turbulence regime changes from fully convective, close to homogeneous and isotropic, toward a more heterogeneous and intermittent state. These issues motivated the BLLAST (Boundary-Layer Late Afternoon and Sunset Turbulence) field campaign that was conducted from 14 June to 8 July 2011 in southern France, in an area of complex and heterogeneous terrain. A wide range of instrumented platforms including full-size aircraft, remotely piloted aircraft systems, remote-sensing instruments, radiosoundings, tethered balloons, surface flux stations and various meteorological towers were deployed over different surface types. The boundary layer, from the earth's surface to the free troposphere, was probed during the entire day, with a focus and intense observation periods that were conducted from midday until sunset. The BLLAST field campaign also provided an opportunity to test innovative measurement systems, such as new miniaturized sensors, and a new technique for frequent radiosoundings of the low troposphere. Twelve fair weather days displaying various meteorological conditions were extensively documented during the field experiment. The boundary-layer growth varied from one day to another depending on many contributions including stability, advection, subsidence, the state of the previous day's residual layer, as well as local, meso-or synoptic scale conditions. Ground-based measurements combined with tethered-balloon and airborne observations captured the turbulence decay from the surface throughout the whole boundary layer and documented the evolution of the turbulence characteristic length scales during the transition period. Closely integrated with the field experiment, numerical studies are now underway with a complete hierarchy of models to support the data interpretation and improve the model representations.

Purpose: Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is an acquired inflammatory disorder affecting the retina, retinal pigment epithelium, and choroid of healthy adults. APMPPE has been reported to occur after diverse infectious diseases, suggesting a possible immune disorder. The primary site of inflammation remains hypothetical.Methods/results: A previously healthy 37-year-old patient developed APMPPE soon after the onset of mumps. Indocyanine green angiography (ICGA) revealed numerous hypofluorescent lesions throughout the posterior pole, outnumbering the lesions detectable either ophthalmoscopically or on fluorescein angiography. The hypofluorescent lesions visible on ICGA disappeared on follow-up studies.Conclusion: This case represents the first reported patient with AMPPE following mumps. Our results suggest that a multifocal choroidopathy might be the underlying cause of APMPPE. [ABSTRACT FROM AUTHOR]

Transcription presents challenges to genome stability both directly, by altering genome topology and exposing single-stranded DNA to chemical insults and nucleases, and indirectly by introducing obstacles to the DNA replication machinery. Such obstacles include the RNA polymerase holoenzyme itself, DNA-bound regulatory factors, G-quadruplexes and RNA-DNA hybrid structures known as R-loops. Here, we review the detrimental impacts of transcription on genome stability in budding yeast, as well as the mitigating effects of transcription-coupled nucleotide excision repair and of systems that maintain DNA replication fork processivity and integrity. Interactions between DNA replication and transcription have particular potential to induce mutation and structural variation, but we conclude that such interactions must have only minor effects on DNA replication by the replisome with little if any direct mutagenic outcome. However, transcription can significantly impair the fidelity of replication fork rescue mechanisms, particularly Break Induced Replication, which is used to restart collapsed replication forks when other means fail. This leads to de novo mutations, structural variation and extrachromosomal circular DNA formation that contribute to genetic heterogeneity, but only under particular conditions and in particular genetic contexts, ensuring that the bulk of the genome remains extremely stable despite the seemingly frequent interactions between transcription and DNA replication., (© 2024 The Authors. Yeast published by John Wiley & Sons Ltd.)

The massive accumulation of extrachromosomal ribosomal DNA circles (ERCs) in yeast mother cells has been long cited as the primary driver of replicative ageing. ERCs arise through ribosomal DNA (rDNA) recombination, and a wealth of genetic data connects rDNA instability events giving rise to ERCs with shortened life span and other ageing pathologies. However, we understand little about the molecular effects of ERC accumulation. Here, we studied ageing in the presence and absence of ERCs, and unexpectedly found no evidence of gene expression differences that might indicate stress responses or metabolic feedback caused by ERCs. Neither did we observe any global change in the widespread disruption of gene expression that accompanies yeast ageing, altogether suggesting that ERCs are largely inert. Much of the differential gene expression that accompanies ageing in yeast was actually associated with markers of the senescence entry point (SEP), showing that senescence, rather than age, underlies these changes. Cells passed the SEP irrespective of ERCs, but we found the SEP to be associated with copy number amplification of a region of chromosome XII between the rDNA and the telomere (ChrXIIr) forming linear fragments up to approximately 1.8 Mb size, which arise in aged cells due to rDNA instability but through a different mechanism to ERCs. Therefore, although rDNA copy number increases dramatically with age due to ERC accumulation, our findings implicate ChrXIIr, rather than ERCs, as the primary driver of senescence during budding yeast ageing., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zylstra et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Aim: Ophthalmological complications associated with Berger's IgA nephropathy comprise scleritis, episcleritis, keratoconjunctivitis as well as anterior uveitis. We present a new association of IgA nephropathy with a retinal vasculopathy., Methods: Presentation of two clinical cases., Results: Two patients presented with hematuria and epistaxis associated with a retinal vasculopathy characterised by teleangiectasies, capillary occlusion with retinal hemorrhages, neovascularisations and macular edema with decreased visual acuity. Fluorescein angiography showed zones of non-perfusion as well as vasculitic changes. A general medical exam revealed a normal arterial pressure but a slightly elevated creatinine. Immunological investigations for the presence of antibodies showed no positive results. Renal biopsy demonstrated mesangial proliferations with diffuse deposits of IgA. Over the course of a 2 year follow-up some of the retinal changes regressed under treatment with cortisone and visual acuity returned to normal. The teleangiectasies showed no progression., Conclusion: Berger's IgA nephropathy can be associated with a retinal vasculopathy which may be due to local deposition of IgA immune complexes in the retinal vessels.

Objective: To evaluate short-term safety and the effects on visual acuity and fluorescein angiography of single or multiple sessions of photodynamic therapy with verteporfin for choroidal neovascularization (CNV) not related to age-related macular degeneration (AMD), including pathologic myopia, the ocular histoplasmosis syndrome, angioid streaks, and idiopathic causes., Design: A nonrandomized, multicenter, open-label, dose-escalation phase 1 and 2 clinical trial., Setting: Four ophthalmic centers in Europe and North America providing retinal care., Participants: Thirteen patients with subfoveal CNV due to pathologic myopia, the ocular histoplasmosis syndrome, angioid streaks, or idiopathic causes., Methods: Standardized protocol refraction, visual acuity testing, ophthalmic examinations, color photographs, and fluorescein angiograms were used to evaluate the results of photodynamic therapy treatments with verteporfin. Follow-up ranged from 12 weeks for patients who were treated once to 43 weeks for patients who were treated up to 4 times., Results: Verteporfin therapy was well tolerated in patients with CNV not related to AMD. No deterioration in visual acuity was observed; most patients gained at least 1 line of vision. Reduction in the size of leakage area from classic CNV was noted in all patients as early as 1 week after verteporfin therapy, with complete absence of leakage from classic CNV in almost half of the patients. Improvement in visual acuity after verteporfin therapy was greatest (+6, +8, and +9 lines) in 3 patients with relatively poor initial visual acuity (between 20/200 and 20/800). Up to 4 treatments were found to have short-term safety even with retreatment intervals as short as 4 weeks., Conclusions: Treatment of CNV not related to AMD with verteporfin therapy achieves short-term cessation of fluorescein leakage from CNV in a small number of patients without loss of vision. Further randomized clinical trials including a larger number of patients are under way to confirm whether verteporfin therapy is beneficial for subfoveal CNV not related to AMD.

Indocyanine green (ICG) angiography is a new diagnostic modality that was suggested, in small series, to provide a typical angiographic pattern in cases of choroidal hemangioma. Our study, through an exceptionally large series of 75 patients, assessed in a prospective way whether a typical ICG pattern of choroidal hemangioma exists and what would be its possible variations. The most constant feature is the sequence of the different ICG angiographic phases. The arterial phase demonstrates the filling of intratumoral vessels on a hypofluorescent tumoral background. During the venous phase, the hemangioma reaches a stage of maximal ICG-A fluorescence, with superimposed hyper- and hypofluorescent spots. Sturge-Weber cases have also extratumoral hyperfluorescent spots. The late phase shows a hypofluorescent lesion with residual hyperfluorescent caverns and a well-delineated, but complex border structure., (Copyright 2000 S. Karger AG, Basel.)

Purpose: To describe the characteristic findings of fundus flavimaculatus (Stargardt disease) as seen on indocyanine green angiography., Methods: Twelve eyes of 6 consecutive patients with fundus flavimaculatus were studied by fundus color photographs, fluorescein angiography and indocyanine green angiography., Results: Indocyanine green angiography allowed visualization of small, clearly demarcated areas in which hypofluorescence increased over time, leading eventually to a large reticular pattern with small areas of normal-appearing choroid encircled by a well-defined network of hypofluorescent curvilinear lesions. These hypofluorescent flecks were present in all 12 eyes but corresponded only partially to the yellow flecks visible on biomicroscopy of the fundus. The peripapillary area was well preserved on indocyanine green angiography and the periphery did not show any visible abnormalities., Conclusions: The hypofluorescent curvilinear areas visualized on indocyanine green angiography form a reticular pattern that is similar to the polygonal shape of the watershed zones between terminal choroidal arterioles, which supply the choriocapillaris. These dark areas may reflect choriocapillaris defects secondary to lysis of lipofuscin-engorged retinal pigment epithelial cells. The typical lesions of fundus flavimaculatus thus seem to be situated in areas of least vascular supply. Their absence in the peripapillary area, which benefits from anastomotic vascular connections, would support this hypothesis., (Copyright 2000 S. Karger AG, Basel.)

Objective: To evaluate the safety and short-term visual and fluorescein angiographic effects of a single photodynamic therapy treatment with verteporfin with the use of different dosage regimens in patients with choroidal neovascularization (CNV) from age-related macular degeneration., Design: Nonrandomized, multicenter, open-label, clinical trial using 5 dosage regimens., Setting: Four ophthalmic centers in North America and Europe providing retinal care., Participants: Patients with subfoveal CNV caused by age-related macular degeneration., Methods: Standardized protocol refraction, visual acuity testing, ophthalmic examination, color photographs, and fluorescein angiograms were used to evaluate the effects of a single treatment of photodynamic therapy with verteporfin. Follow-up was planned through 3 months in 97 patients and for less than 3 months in 31 other patients., Results: The mean visual acuity change (and range of change) from baseline at the follow-up examination at week 12 after a single treatment with regimens 1 through 5 was -0.2 (-3 to +2), -0.9 (-9 to +5), -1.6 (-9 to +2), +0.4 (-8 to +7), and +0.1 (-8 to +9) lines, respectively. Only the highest light dose (150 J/cm2) in regimens 2 and 3, which produced angiographic nonperfusion of neurosensory retinal vessels, caused marked vision loss. Some cessation of fluorescein leakage from CNV was achieved without loss of vision when the light dose used was less than 150 J/cm2. Systemic adverse events were rare. Cessation of fluorescein leakage from CNV was noted in all regimens by 1 week after photodynamic therapy. Fluorescein leakage from at least a portion of the CNV reappeared by 4 to 12 weeks after treatment in almost all cases. Progression of classic CNV beyond the area of CNV identified before treatment was noted in 42 (51%) of the 83 eyes with classic CNV followed up for 3 months after a single treatment. Eyes in which the area of any CNV leakage at 12 weeks was less than at baseline had a significantly better visual acuity outcome (+0.8 line) than eyes in which CNV leakage progressed (-0.8 line)., Conclusions: Photodynamic therapy with verteporfin achieved short-term cessation of fluorescein leakage from CNV without loss of vision or growth of classic CNV in some patients with age-related macular degeneration. Except for nonperfusion of neurosensory retinal vessels at a light dose of 150 J/cm2, no other adverse events were of concern. Randomized clinical trials to investigate whether this new modality can preserve vision in patients with CNV secondary to age-related macular degeneration are justified.

Objectives: To evaluate safety and short-term visual acuity and fluorescein angiographic effects of photodynamic therapy (PDT) after retreatments with verteporfin for choroidal neovascularization (CNV) in age-related macular degeneration (AMD) that demonstrated fluorescein leakage after at least 1 course of PDT., Design: Nonrandomized, multicenter, open-label phase 1 and 2 clinical trial using 2 different retreatment dosage regimens., Setting: Four ophthalmic centers in Europe and North America providing retinal care., Methods: Standardized protocol refraction, visual acuity testing, ophthalmic examinations, color photographs, and fluorescein angiograms were used to evaluate the results of multiple PDT treatments. Two regimens (regimens 2 and 4) for treatment and retreatment were chosen from 5 used in a single-treatment study. Both regimens used a verteporfin dose of 6 mg/m2 infused for 10 minutes. However, regimen 2 used a light dose of 100 J/cm2 applied 20 minutes after the start of the verteporfin infusion, whereas regimen 4 used a light dose of 50, 75, or 100 J/cm2 applied 15 minutes after infusion commenced. Posttreatment evaluations were planned in 31 participants up to 3 months after up to 2 retreatments given at 2- or 4-week intervals after initial PDT treatment. Similar posttreatment evaluations were planned after retreatments in 5 additional participants who were reenrolled some time more than 12 weeks after an initial PDT treatment., Results: The average visual acuity change for the 31 participants who had retreatment within 2 to 4 weeks after the initial treatment and a follow-up examination 16 to 20 weeks after the initial treatment was 0.2 lines (range, -4 to 4 lines) in regimen 2 and -1.0 line (range, -5 to 3 lines) in regimen 4. Similar outcomes were noted in the 5 reenrolled participants. Cessation of fluorescein leakage from classic CNV for at least 1 to 4 weeks could be achieved without loss of visual acuity after at least 2 treatments in 2 (6.5%) of 31 patients. Similar to single-treatment effects, the disappearance of leakage was documented regularly at 1 week after each retreatment. Fluorescein leakage reappeared by 4 to 12 weeks after a retreatment in almost all cases. However, compared with baseline, leakage activity appeared to be reduced after multiple PDT courses. For the 31 patients who had follow-up for 3 months after the last retreatment and had received retreatment 2 to 4 weeks after the initial treatment, progression of CNV beyond the area identified before the retreatment was noted in 10 (48%) of the 21 eyes with classic CNV in regimen 2 and 9 (90%) of 10 eyes in regimen 4. The rate and severity of ocular or systemic adverse events were not increased by multiple applications., Conclusions: Multiple applications of PDT with verteporfin achieve repetitive, short-term cessation of fluorescein leakage from CNV secondary to AMD, without loss of visual acuity. This strategy can be used in randomized clinical trials investigating the efficacy of verteporfin in PDT for recurrent fluorescein dye leakage from persistent or recurrent CNV, following an initial or subsequent PDT treatment, with maintenance of visual acuity. Retreatments may achieve progressive cessation of leakage and prevent further growth of CNV and subsequent visual loss.

Malattia Leventinese (ML) and Doyne honeycomb retinal dystrophy (DHRD) refer to two autosomal dominant diseases characterized by yellow-white deposits known as drusen that accumulate beneath the retinal pigment epithelium (RPE). Both loci were mapped to chromosome 2p16-21 (refs 5,6) and this genetic interval has been subsequently narrowed. The importance of these diseases is due in large part to their close phenotypic similarity to age-related macular degeneration (AMD), a disorder with a strong genetic component that accounts for approximately 50% of registered blindness in the Western world. Just as in ML and DHRD, the early hallmark of AMD is the presence of drusen. Here we use a combination of positional and candidate gene methods to identify a single non-conservative mutation (Arg345Trp) in the gene EFEMP1 (for EGF-containing fibrillin-like extracellular matrix protein 1) in all families studied. This change was not present in 477 control individuals or in 494 patients with age-related macular degeneration. Identification of this mutation may aid in the development of an animal model for drusen, as well as in the identification of other genes involved in human macular degeneration.

Objective: To analyze the retinal and choroidal vascular abnormalities in eyes with angioid streaks (AS) associated with pseudoxanthoma elasticum (PXE)., Methods: Color photographs and fluorescein angiograms of 54 eyes of 27 consecutive patients with AS and PXE were examined retrospectively., Results: Four (7%) of the 54 eyes had a major vascular abnormality at the level of the disc; this took the form of a large vascular loop corresponding to an arteriovenous communication between retina and choroid in 3 eyes (6%) and an anastomosis between 2 retinal arteries in 1 eye (2%)., Conclusion: Analysis of the vascular network in these eyes showed several vascular abnormalities, among which chorioretinal arteriovenous communications appear to be the most dramatic.

Purpose: The RHO C110Y mutation has been recently reported to cause a phenotypically unspecified form of autosomal dominant retinitis pigmentosa (adRP). The study of a family affected with this mutation allowed us to hereby describe the genotype/phenotype correlation associated with the RHO C110Y mutation., Methods: A six-generation pedigree cosegregating adRP and RHO C110Y in ten accessible individuals was ophthalmologically investigated. All family members affected with RP went through complete eye examination and ERG testing., Results: The disease first manifested with nyctalopia during adulthood and slowly progressed over the next decades towards tubular visual field defects and relatively preserved central vision. Ophthalmoscopically, the fundus remained almost unaltered until the end of the third decade of life, and then slowly progressed towards typical RP changes with minimal macular involvement by the eighth decade. Color vision remained unaltered. Earliest ERG alteration was limited to the rod system followed by a rod-cone pattern. Scotopic and photopic ERG were recordable until the fourth and sixth decades, respectively., Discussion: RHO C110Y-associated adRP is characterized by a late onset and a mild progression compatible with type 2 or regional RP with little intrafamilial phenotypic variability and complete penetrance. Characterization of genotype-phenotype correlations plays a role in the improvement of genetic and prognostic counselling.

Purpose: Phenotypic, genetic and molecular characterization of 69 index patients with retinitis pigmentosa (RP) and various inherited retinal diseases., Patients and Method: patients went through complete ocular examination and blood samples were drawn for mutational screening of three candidate genes: rhodopsin (RHO), peripherin/RDS, and ROM-1., Results: the most frequent type of RP among our population was the autosomal dominant (43.6%). Three RHO mutations were found among the RP patients. A RDS mutation was detected in three unrelated families segregating dominant macular dystrophy., Discussion and Conclusions: 18% of the autosomal dominant RP patients presented a RHO mutation; RDS R172W mutation was present in 25% of the dominant macular dystrophies.

Background: Conventional photocoagulation of subfoveal choroidal neovascularization (CNV) is often accompanied by visual loss due to thermal damage to adjacent retinal structures. Photodynamic therapy (PDT) allows vascular occlusion by selective photochemical destruction of vascular endothelial cells only. In a pilot study we evaluated the use of PDT in CNV., Methods: In a clinical phase I/II trial, patients with subfoveal CNV were treated with PDT. Benzoporphyrin derivative monoacid ring A (BPD) was used as sensitizer at a drug dose of 6 mg/m2 or 12 mg/m2. Irradiation was performed via a diode laser emitting at 690 nm coupled into a slit lamp. Safe and maximum tolerated light doses were defined by dose escalation from 25 to 150 J/cm2. Photodynamic effects were documented ophthalmoscopically and angiographically., Results: Sixty-one patients received a single course of BPD-PDT. Preliminary results suggest no damage to retinal structures within the treated area clinically. Retinal perfusion was not altered, while CNV demonstrated immediate absence of fluorescein leakage in the majority of lesions subsequent to PDT. At optimized parameters (6 mg/m2 and 50 J/cm2) complete cessation of leakage from classic CNV occurred in 100% of cases at 1 week and in 50% at week 4. In 70-80% of classic CNV, leakage reappeared at week 12, but markedly less than before treatment., Conclusion: PDT allows temporary absence of leakage from CNV with preservation of visual acuity. The long-term prognosis of CNV secondary to age-related macular degeneration treated with repeated courses of PDT is being evaluated in a phase III trial.

Purpose: To define the morphometric characteristics of indirect choroidal ruptures associated with choroidal neovascularization (CNV)., Methods: A total of 79 eyes that had sustained traumatic indirect choroidal ruptures was studied retrospectively. Color pictures of the fundus and fluorescein angiograms were available in all cases, and patients were followed for at least 1 year. Eyes that were free of CNV constituted Group I; eyes that developed CNV constituted Group II. Baseline characteristics of both groups, including age, sex, and visual acuity, were recorded. Distance of indirect choroidal ruptures from the center of the fovea and morphometric characteristics of the ruptures were calculated using image analysis software (Image 1.60; National Institutes of Health, Bethesda, MD)., Results: A total of 63 eyes (79.7%) free of CNV was included in Group I and 16 eyes (20.3%) that developed CNV were included in Group II. Morphometric analysis showed a greater distance between the indirect choroidal rupture and the center of the fovea in Group I than in Group II (median, 1480 microm versus 612 microm; P = 0.009). In addition, the length of the rupture was shorter in Group I than in Group II (median, 3054 microm versus 4504 microm; P = 0.03)., Conclusions: Two significant factors associated with the presence of CNV in case of traumatic choroidal rupture were identified and quantified: the proximity of the rupture to the center of the fovea and the length of the rupture. Both should be considered as risk factors for the development of CNV and monitoring should take them into account.

Mycoplasma pneumoniae is an atypical bacterium that can cause a great variety of respiratory infections and be responsible for ocular involvement such as conjunctivitis, anterior uveitis and very rarely optic neuropathy. We report herein an additional case of bilateral optic disc swelling with profound visual loss following Mycoplasma pneumoniae pneumonia and review the world literature on the ocular manifestations associated with this pathogen.