Analysis of neuroretinal rim distribution and vascular pattern in eyes with presumed large physiological cupping: a comparative study

Background: To investigate possible differences in neuroretinal rim distribution, vascular pattern, and peripapillary region appearance between eyes with presumed large physiological optic disc cupping (pLPC) and eyes with minimal optic disc excavation.Methods: We prospectively enrolled consecutive subjects with pLPC and individuals with minimal excavation (optic disc excavation within normal limits; control group). All eyes had normal visual fields and untreated intraocular pressure (IOP) = 0.6 and >= 30 months of follow-up with no evidence of glaucomatous neuropathy. for controls, VCDR was limited to <= 0.5. We compared ocular signs and characteristics related to the neuroretinal rim distribution, vascular pattern, peripapillary region appearance and disc size between groups. Whenever both eyes were eligible, one was randomly selected for analysis.Results: A total of 74 patients (mean age, 45.6 +/- 14.9 years) with pLPC and 45 controls (mean age, 44.8 +/- 11.6 years) were enrolled (p = 0.76). Median disc size and VCDR was significantly larger in eyes with pLPC compared to controls (p < 0.01). the proportion of eyes with violation of the ISNT rule, laminar dot sign, nasal shifting of the central vessels, nasal excavation and baring of circumlinear vessel was significantly greater in the eyes with pLPC compared to controls (p < 0.01). There were no significant differences regarding the proportions of eyes with peripapillary atrophy between groups (p < 0.09). Finally, disc size was significantly associated with VCDR (r(2) = 0.47, p < 0.01), with an increase of 0.21 in VCDR for each 1 mm(2) in disc area.Conclusion: Compared to normal controls, eyes with pLPC may present a higher proportion of optic nerve head findings frequently observed in glaucomatous eyes. This seems to be explained in part by the larger discs found in these eyes. We believe care should be taken while classifying them as glaucomatous or not based solely on these characteristics.Universidade Federal de São Paulo, Dept Ophthalmol, BR-04021001 São Paulo, BrazilHosp Med Olhos, Glaucoma Unit, BR-06018180 Osasco, SP, BrazilMayo Clin, Dept Ophthalmol, Jacksonville, FL 32224 USAUniversidade Federal de São Paulo, Dept Ophthalmol, BR-04021001 São Paulo, BrazilWeb of Scienc

Large-scale Mitogenomics Enables Insights Into Schizophora (diptera) Radiation And Population Diversity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)True flies are insects of the order Diptera and encompass one of the most diverse groups of animals on Earth. Within dipterans, Schizophora represents a recent radiation of insects that was used as a model to develop a pipeline for generating complete mitogenomes using various sequencing platforms and strategies. 91 mitogenomes from 32 different species were sequenced and assembled with high fidelity, using amplicon, whole genome shotgun or single molecule sequencing approaches. Based on the novel mitogenomes, we estimate the origin of Schizophora within the Cretaceous-Paleogene (K-Pg) boundary, about 68.3 Ma. Detailed analyses of the blowfly family (Calliphoridae) place its origin at 22 Ma, concomitant with the radiation of grazing mammals. The emergence of ectoparasitism within calliphorids was dated 6.95 Ma for the screwworm fly and 2.3 Ma for the Australian sheep blowfly. Varying population histories were observed for the blowfly Chrysomya megacephala and the housefly Musca domestica samples in our dataset. Whereas blowflies (n = 50) appear to have undergone selective sweeps and/or severe bottlenecks in the New World, houseflies (n = 14) display variation among populations from different zoogeographical zones and low levels of gene flow. The reported highthroughput mitogenomics approach for insects enables new insights into schizophoran diversity and population history of flies.6FAPESP [09/51723-7]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [08/56769-2, 10/09961-5, 12/23200-2]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Mecanismos de fechamento angular sem bloqueio pupilar: análise de prevalência e resultados terapêuticos

Purpose: To assess the prevalence and treatment outcomes of angle-closure mechanisms other than pupillary block in a population of Brazilian patients.Methods: A retrospective chart review was conducted to evaluate patients who had undergone laser peripheral iridotomy (LPI) due to occludable angles at a single institution between July 2009 and April 2012. An occludable angle was defined as an eye in which the posterior trabecular meshwork was not visible for >= 180 degrees on dark-room gonioscopy. Key exclusion criteria were any form of secondary glaucoma and the presence of >90 degrees of peripheral anterior synechiae. Collected data were age, race, gender, angle-closure mechanism (based on indentation goniocopy and ultrasound biomicroscopy), intraocular pressure (IOP), number of antiglaucoma medications and subsequent management during follow-up. If both eyes were eligible, the right eye was arbitrarily selected for analysis.Results: A total of 196 eyes of 196 consecutive patients (mean age 58.3 +/- 11.6 years) who underwent LPI were included. in most of the patients [86% (169 patients; 133 women and 36 men]), LPI sucessfully opened the angle. Mean IOP was reduced from 18.3 +/- 6.4 mmHg to 15.4 +/- 4.5 mmHg after LPI (p<0.01). Among the 27 patients with persistent occludable angles, the most common underlying mechanisms were plateau iris (56%) and lens-induced component (34%). Most of these patients (85%) were treated with argon laser peripheral iridoplasty (ALPI); approximately 90% showed non-occludable angles following the laser procedure (mean IOP reduction of 18.9%), with no significant differences between patients with plateau iris and lens-induced components (p=0.34; mean follow-up of 11.4 +/- 3.6 months).Conclusions: Our findings suggest that, in this population of Brazilian patients, several eyes with angle closure were not completely treated with LPI. in the present large case series involving middle-age patients, plateau iris was the leading cause of persistent angle closure and was effectively treated with ALPI. A detailed eye examination with indentation gonioscopy should always be performed after LPI to rule out persistent angle closure due to non-pupillary block mechanisms.Hosp Med Olhos, Glaucoma Unit, Osasco, SP, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilMayo Clin, Jacksonville, FL 32224 USAUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

AimAmazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types.LocationAmazonia.TaxonAngiosperms (Magnoliids; Monocots; Eudicots).MethodsData for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny.ResultsIn the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types.Main ConclusionNumerous tree lineages, including some ancient ones (&gt;66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions