Demography of an ice-obligate mysticete in a region of rapid environmental change.

Antarctic minke whales (Balaenoptera bonaerensis, AMW) are an abundant, ice-dependent species susceptible to rapid climatic changes occurring in parts of the Antarctic. Here, we used remote biopsy samples and estimates of length derived from unoccupied aircraft system (UAS) to characterize for the first time the sex ratio, maturity, and pregnancy rates of AMWs around the Western Antarctic Peninsula (WAP). DNA profiling of 82 biopsy samples (2013-2020) identified 29 individual males and 40 individual females. Blubber progesterone levels indicated 59% of all sampled females were pregnant, irrespective of maturity. When corrected for sexual maturity, the median pregnancy rate was 92.3%, indicating that most mature females become pregnant each year. We measured 68 individuals by UAS (mean = 8.04 m) and estimated that 66.5% of females were mature. This study provides the first data on the demography of AMWs along the WAP and represents the first use of non-lethal approaches to studying this species. Furthermore, these results provide baselines against which future changes in population status can be assessed in this rapidly changing marine ecosystem.

Variation in blubber cortisol levels in a recovering humpback whale population inhabiting a rapidly changing environment.

Glucocorticoids are regularly used as biomarkers of relative health for individuals and populations. Around the Western Antarctic Peninsula (WAP), baleen whales have and continue to experience threats, including commercial harvest, prey limitations and habitat change driven by rapid warming, and increased human presence via ecotourism. Here, we measured demographic variation and differences across the foraging season in blubber cortisol levels of humpback whales (Megaptera novaeangliae) over two years around the WAP. Cortisol concentrations were determined from 305 biopsy samples of unique individuals. We found no significant difference in the cortisol concentration between male and female whales. However, we observed significant differences across demographic groups of females and a significant decrease in the population across the feeding season. We also assessed whether COVID-19-related reductions in tourism in 2021 along the WAP correlated with lower cortisol levels across the population. The decline in vessel presence in 2021 was associated with a significant decrease in humpback whale blubber cortisol concentrations at the population level. Our findings provide critical contextual data on how these hormones vary naturally in a population over time, show direct associations between cortisol levels and human presence, and will enable comparisons among species experiencing different levels of human disturbance.

Brain Abnormalities in Patients with Germline Variants in H3F3: Novel Imaging Findings and Neurologic Symptoms Beyond Somatic Variants and Brain Tumors.

BACKGROUND AND PURPOSE: Pathogenic somatic variants affecting the genes Histone 3 Family 3A and 3B (H3F3) are extensively linked to the process of oncogenesis, in particular related to central nervous system tumors in children. Recently, H3F3 germline missense variants were described as the cause of a novel pediatric neurodevelopmental disorder. We aimed to investigate patterns of brain MR imaging of individuals carrying H3F3 germline variants. MATERIALS AND METHODS: In this retrospective study, we included individuals with proved H3F3 causative genetic variants and available brain MR imaging scans. Clinical and demographic data were retrieved from available medical records. Molecular genetic testing results were classified using the American College of Medical Genetics criteria for variant curation. Brain MR imaging abnormalities were analyzed according to their location, signal intensity, and associated clinical symptoms. Numeric variables were described according to their distribution, with median and interquartile range. RESULTS: Eighteen individuals (10 males, 56%) with H3F3 germline variants were included. Thirteen of 18 individuals (72%) presented with a small posterior fossa. Six individuals (33%) presented with reduced size and an internal rotational appearance of the heads of the caudate nuclei along with an enlarged and squared appearance of the frontal horns of the lateral ventricles. Five individuals (28%) presented with dysgenesis of the splenium of the corpus callosum. Cortical developmental abnormalities were noted in 8 individuals (44%), with dysgyria and hypoplastic temporal poles being the most frequent presentation. CONCLUSIONS: Imaging phenotypes in germline H3F3-affected individuals are related to brain features, including a small posterior fossa as well as dysgenesis of the corpus callosum, cortical developmental abnormalities, and deformity of lateral ventricles.

The rare C9 P167S risk variant for age-related macular degeneration increases polymerization of the terminal component of the complement cascade.

Age-related macular degeneration (AMD) is a complex neurodegenerative eye disease with behavioral and genetic etiology and is the leading cause of irreversible vision loss among elderly Caucasians. Functionally significant genetic variants in the alternative pathway of complement have been strongly linked to disease. More recently, a rare variant in the terminal pathway of complement has been associated with increased risk, Complement component 9 (C9) P167S. To assess the functional consequence of this variant, C9 levels were measured in two independent cohorts of AMD patients. In both cohorts, it was demonstrated that the P167S variant was associated with low C9 plasma levels. Further analysis showed that patients with advanced AMD had elevated sC5b-9 compared to those with non-advanced AMD, although this was not associated with the P167S polymorphism. Electron microscopy of membrane attack complexes (MACs) generated using recombinantly produced wild type or P167S C9 demonstrated identical MAC ring structures. In functional assays, the P167S variant displayed a higher propensity to polymerize and a small increase in its ability to induce hemolysis of sheep erythrocytes when added to C9-depleted serum. The demonstration that this C9 P167S AMD risk polymorphism displays increased polymerization and functional activity provides a rationale for the gene therapy trials of sCD59 to inhibit the terminal pathway of complement in AMD that are underway.

Factors affecting anatomical and visual outcome after macular hole surgery: findings from a large prospective UK cohort.

OBJECTIVES: To reassess the definition of a large macular hole, factors predicting hole closure and post-surgery visual recovery. DESIGN: Database study of 1483 primary macular hole operations. Eligible operations were primary MH operations treated with a vitrectomy and a gas or air tamponade. Excluded were eyes with a history of retinal detachment, high myopia, previous vitrectomy or trauma. RESULTS: A higher proportion of operations were performed in eyes from females (71.1%) who were 'on average' younger (p < 0.001), with slightly larger holes (p < 0.001) than male patients. Sulfur hexafluoride gas was generally used for smaller holes (p < 0.001). From 1253 operations with a known surgical outcome, successful hole closure was achieved in 1199 (96%) and influenced by smaller holes and complete ILM peeling (p < 0.001), but not post-surgery positioning (p = 0.072). A minimum linear diameter of ~500 µm marked the threshold where the success rate started to decline. From the 1056 successfully closed operations eligible for visual outcome analysis, visual success (defined as visual acuity of 0.30 or better logMAR) was achieved in 488 (46.2%) eyes. At the multivariate level, the factors predicting visual success were better pre-operative VA, smaller hole size, shorter duration of symptoms and the absence of AMD. CONCLUSIONS: Females undergoing primary macular hole surgery tend to be younger and have larger holes than male patients. The definition of a large hole should be changed to around 500 µm, and patients should be operated on early to help achieve a good post-operative VA.

Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species.

Understanding how dispersal and gene flow link geographically separated the populations over evolutionary history is challenging, particularly in migratory marine species. In southern right whales (SRWs, Eubalaena australis), patterns of genetic diversity are likely influenced by the glacial climate cycle and recent history of whaling. Here we use a dataset of mitochondrial DNA (mtDNA) sequences (n = 1327) and nuclear markers (17 microsatellite loci, n = 222) from major wintering grounds to investigate circumpolar population structure, historical demography and effective population size. Analyses of nuclear genetic variation identify two population clusters that correspond to the South Atlantic and Indo-Pacific ocean basins that have similar effective breeder estimates. In contrast, all wintering grounds show significant differentiation for mtDNA, but no sex-biased dispersal was detected using the microsatellite genotypes. An approximate Bayesian computation (ABC) approach with microsatellite markers compared the scenarios with gene flow through time, or isolation and secondary contact between ocean basins, while modelling declines in abundance linked to whaling. Secondary-contact scenarios yield the highest posterior probabilities, implying that populations in different ocean basins were largely isolated and came into secondary contact within the last 25,000 years, but the role of whaling in changes in genetic diversity and gene flow over recent generations could not be resolved. We hypothesise that these findings are driven by factors that promote isolation, such as female philopatry, and factors that could promote dispersal, such as oceanographic changes. These findings highlight the application of ABC approaches to infer the connectivity in mobile species with complex population histories and, currently, low levels of differentiation.

Does bariatric surgery prevent progression of diabetic retinopathy?

PurposeTo assess the changes in diabetic retinopathy (DR) in type 2 diabetes (T2DM) patients post bariatric surgery and report on the risk factors that may be associated with it.Patients and methodsRetrospective observational study of T2DM patients who underwent bariatric surgery in a UK specialist bariatric unit between 2009 and 2015. Preoperative and postoperative weight, HbA1c, and annual DR screening results were collected from medical records. Patients with preoperative retinal screening and at least one postoperative retinal screening were eligible for analysis. Multivariate analysis was used to explore significant clinical predictors on postoperative worsening in DR.ResultsA total of 102 patients were eligible for analysis and were followed up for 4 years. Preoperatively, 68% of patients had no DR compared to 30% with background retinopathy, 1% pre-proliferative retinopathy, and 1% proliferative retinopathy. In the first postoperative visit, 19% of patients developed new DR compared to 70% stable and 11% improved. These proportions remained similar for each postoperative visit over time. Young age, male gender, high preoperative HbA1c, and presence of preoperative retinopathy were the significant predictors of worsening postoperatively.ConclusionBariatric surgery does not prevent progression of DR. Young male patients with pre-existing DR and poor preoperative glycaemic control are most at risk of progression. All diabetic patients should attend regular DR screening post bariatric surgery to allow early detection of potentially sight-threatening changes, particularly among those with identifiable risk factors. Future prospective studies with prolonged follow-up are required to clarify the duration of risk.

Characteristics, socioeconomic status and ethnic variations of primary idiopathic macular hole repair in vitreoretinal centers in the United Kingdom.

OBJECTIVE: The purpose of this multicentre retrospective study was to investigate the characteristics and role of ethnicity and socioeconomic status amongst patients with idiopathic macular holes (IMH) and the surgical outcome. SUBJECTS AND METHOD: Consecutive patients undergoing primary IMH surgery at three vitreoretinal units in the UK (King's College Hospital, London, UK, Western Eye Hospital, London, UK, Sunderland Eye Infirmary, Sunderland, UK) between January 2007 and May 2017 were included. The main outcome measure was anatomical closure of IMH. RESULTS: Two hundred and thirty three primary IMH surgeries were included. All patients underwent pars plana vitrectomy, internal limiting membrane peeling, and gas tamponade. 69.10% of patients were European Caucasian, 6.44% were Asian, and 24.46% were Afro-Caribbean. The mean base macular hole diameter (BD) was 475.5mcm. Mean BD was 432.2mcm in European Caucasian patients, 481.3mcm in Asians (P=0.005), and 505.61mcm in Afro-Caribbeans (P=0.006). Regression analysis demonstrated that BD and Afro-Caribbean ethnicity were independent significant risk factors for surgical failure. Those who have longer duration of symptoms (Afro-Caribbeans) and leave in more deprived places (Afro-Caribbeans) in England where found to have lower success rate on macular hole closure. CONCLUSION: Asian and Afro-Caribbean patients present with larger IMH than European Caucasians. In addition to IMH base diameter, black origin and lower socioeconomic status are independent risk factors for surgical failure. This study presents a large population-based data analysis on ethnic variation in macular holes and may assist in the management and predicting the surgical outcome.

Real world outcomes of ocriplasmin use by members of the British and Eire Association of Vitreoretinal Surgeons.

PurposeTo describe a survey of the use of ocriplasmin by members of the British and Eire Association of VitreoRetinal Surgeons (BEAVRS) for VitreoMacular Traction (VMT) and Full Thickness Macular Hole (FTMH) and compare it to published MIVI TRUST trial data.MethodsAll 173 BEAVRS members were contacted by email in October 2014 requesting data on all cases treated with ocriplasmin up to that date. The total number of cases, FTMH closure rate, VMT release rate and the frequency of adverse events were recorded. Results were compared with trial data.Results48 members responded reporting results from 241 eyes. The respective BEAVRS and MIVI TRUST trial closure rates for small FTMHs were 42.1 and 58.3% (P=0.09) and for medium FTMH 12.7 and 36.7% (P=0.01). The respective VMT release rates were 34.1 and 37.4% (P=NS). Retinal detachment was observed in 3.3% of the BEAVRS cohort compared with 0.4% in MIVI TRUST. Reduction in visual acuity to <6/60 was observed in 5.8% of the BEAVRS cohort and 0.6% in MIVI TRUST. Other complications not reported in the MIVI TRUST trial included an increase in FTMH basal diameter following unsuccessful ocriplasmin use in 46.9% of BEAVRS cases and zonular instability at the time of subsequent phacoemulsification in 2.4%.ConclusionMacular hole closure rates were lower in the BEAVRS survey than published in the MIVI TRUST trial data. The incidence of adverse events was greater than previously reported. The reasons for these disparities are unknown but could include positive reporting bias inherent to retrospective surveys, treatment and population differences.

Predicting macular hole closure with ocriplasmin based on spectral domain optical coherence tomography.

PurposeTo assess the preoperative features of patients with idiopathic macular hole (IMH) and vitreomacular adhesion (VMA) treated with ocriplasmin (OCP) that can predict successful closure.MethodData were prospectively collected on all patients with IMH treated with OCP in three British ophthalmic centres. Several preoperative variables were recorded including the IMH base diameter (BD), minimum linear diameter (MLD), and VMA width measured on spectral domain optical coherence tomography. Several other IMH indices were derived including a 'width factor', defined as the BD minus the MLD in µm. The occurrence of VMA release and hole closure were used as the main outcome measures.ResultsThirty-three patients in total with IMH were treated with OCP. Two patients developed rhegmatogenous retinal detachment and were excluded. The mean age of the remaining 31 patients was 71 years, and 71% were female. VMA release occurred in 19 of the 31 (61%) patients and macular hole closure in 11 (35%). Width factor was the most predictive feature for closure on multivariate analysis. The deviance R(2) was 67% (P<0.001). An IMH with a width factor of <60 µm had a 95% certainty of closure, whereas if >290 µm then there was less than a 5% chance of closure. Neither VMA width nor MLD alone was associated with VMA release or closure.ConclusionsPatients with macular holes where the BD was close in size to the MLD had an improved probability of closure than holes with wider base configurations.

The design and validation of an optical coherence tomography-based classification system for focal vitreomacular traction.

PURPOSE: To develop and validate a classification system for focal vitreomacular traction (VMT) with and without macular hole based on spectral domain optical coherence tomography (SD-OCT), intended to aid in decision-making and prognostication. METHODS: A panel of retinal specialists convened to develop this system. A literature review followed by discussion on a wide range of cases formed the basis for the proposed classification. Key features on OCT were identified and analysed for their utility in clinical practice. A final classification was devised based on two sequential, independent validation exercises to improve interobserver variability. RESULTS: This classification tool pertains to idiopathic focal VMT assessed by a horizontal line scan using SD-OCT. The system uses width (W), interface features (I), foveal shape (S), retinal pigment epithelial changes (P), elevation of vitreous attachment (E), and inner and outer retinal changes (R) to give the acronym WISPERR. Each category is scored hierarchically. Results from the second independent validation exercise indicated a high level of agreement between graders: intraclass correlation ranged from 0.84 to 0.99 for continuous variables and Fleiss' kappa values ranged from 0.76 to 0.95 for categorical variables. CONCLUSIONS: We present an OCT-based classification system for focal VMT that allows anatomical detail to be scrutinised and scored qualitatively and quantitatively using a simple, pragmatic algorithm, which may be of value in clinical practice as well as in future research studies.

Wide-field imaging and OCT vs clinical evaluation of patients referred from diabetic retinopathy screening.

PURPOSE: Compare wide-field Optomap imaging and optical coherence tomography (OCT) with clinical examination in diabetic retinopathy (DR). METHODS: Patients referred from Diabetic Eye Screening Programmes to three centres underwent dilated ophthalmoscopy and were assigned a DR grade. Wide-field colour imaging and OCT were then examined by the same clinician at that visit and a combined grade was assigned. Independent graders later reviewed the images and assigned an imaging-only grade. These three grades (clinical, combined, and imaging) were compared. The method that detected the highest grade of retinopathy, including neovascularisation, was determined. RESULTS: Two thousand and forty eyes of 1023 patients were assessed. Wide-field imaging compared with clinical examination had a sensitivity and specificity of 73% and 96%, respectively, for detecting proliferative DR, 84% and 69% for sight-threatening DR, and 64% and 90% for diabetic macular oedema. Imaging alone found 35 more eyes with new vessels (19% of eyes with new vessels) and the combined grade found 14 more eyes than clinical examination alone. CONCLUSIONS: Assessment of wide-field images and OCT alone detected more eyes with higher grades of DR compared with clinical examination alone or when combined with imaging in a clinical setting. The sensitivity was not higher as the techniques were not the same, with imaging alone being more sensitive. Wide-field imaging with OCT could be used to assess referrals from DR screening to determine management, to enhance the quality of assessment in clinics, and to follow-up patients whose DR is above the screening referral threshold but does not actually require treatment.