Peripheral refractive changes associated with myopia progression

Purpose.: To evaluate the changes in peripheral refraction profiles associated with myopia progression and treatment modalities used in the Cambridge Anti-Myopia Study. Methods.: One hundred and seventy-seven myopes in the age range of 14 to 22 years were enrolled in the study. The mean spherical equivalent refractive error was −3.12 ± 1.87 diopters (D) and the refractive error of each participant was corrected with contact lenses. The participants were randomly assigned to one of four treatment groups, which included: altered spherical aberration and vision training, altered spherical aberration only, vision training only, and control. Peripheral refractive error was measured using an open field autorefractor in the central 60° of the retina in 10° steps. The refractive error was measured using cycloplegic autorefraction. Two-year refractive progression data and initial peripheral refraction measurements were available in 113 participants. Measurements of peripheral refraction and cycloplegic refraction were obtained at three visits over 2 years in 12-month intervals for 92 participants. Results.: All subjects showed a relative peripheral hyperopia, especially in the nasal retina. A limited magnitude of myopia progression of −0.34 ± 0.36 D over 2 years was found in each of the four groups on average. There were no significant differences in the rate of progression between any of the treatment groups (P > 0.05). Initial peripheral J45 astigmatic refractive error at 20° and 30° in the nasal retina was weakly correlated with progression of myopia over 2 years (r = −0.27, P = 0.004 and r = −0.20, P = 0.040, respectively; n = 113). The change in spherical equivalent peripheral refractive error at 30° nasal retina over time was also significantly correlated with progression of myopia especially at 24 months (r = −0.24, P = 0.017, n = 92). Conclusions.: Relative peripheral hyperopia is associated with myopia. Myopia progression may be weakly linked to changes in the peripheral refraction profiles in the nasal retina. However, a causative link between peripheral refractive error and myopia progression could not be established

The Cambridge Anti-myopia Study: variables associated with myopia progression

Purpose: To identify variables associated with myopia progression and to identify any interaction between accommodative function, myopia progression, age, and treatment effect in the Cambridge Anti-Myopia Study. Methods: Contact lenses were used to improve static accommodation by altering ocular spherical aberration, and vision training was performed to improve dynamic accommodation. One hundred forty-two subjects, aged 14–21 years, were recruited who had a minimum of −0.75D of myopia. Subjects were assigned to contact lens treatment only, vision training only, contact lens treatment and vision training, or control group. Spherical aberration, lag of accommodation, accommodative convergence/accommodation (AC/A) ratio, accommodative facility, ocular biometry, and refractive error were measured at regular intervals throughout the 2-year trial. Results: Ninety-five subjects completed the 24-month trial period. There was no significant difference in myopia progression between the four treatment groups at 24 months. Age, lag of accommodation, and AC/A ratio were significantly associated with myopia progression. There was a significant treatment effect at 12 months in the contact lens treatment group in younger subjects, based on a median split, aged under 16.9 years (p = 0.005). This treatment effect was not maintained over the second year of the trial. Younger subjects experienced a greater reduction in lag of accommodation with the treatment contact lens at 3 months (p = 0.03), compared to older contact lens treatment and control groups. There was no interaction between AC/A ratio and contact lens treatment effect. Conclusions: Age, lag of accommodation, and AC/A ratio were significantly associated with myopia progression. Although there was no significant treatment effect at 24 months, an interaction between age and contact lens treatment suggests younger subjects may be more amenable, at least in the short term, to alteration of the visual system using optical treatments

Dramatic Shifts in Benthic Microbial Eukaryote Communities following the Deepwater Horizon Oil Spill

Benthic habitats harbour a significant (yet unexplored) diversity of microscopic eukaryote taxa, including metazoan phyla, protists, algae and fungi. These groups are thought to underpin ecosystem functioning across diverse marine environments. Coastal marine habitats in the Gulf of Mexico experienced visible, heavy impacts following the Deepwater Horizon oil spill in 2010, yet our scant knowledge of prior eukaryotic biodiversity has precluded a thorough assessment of this disturbance. Using a marker gene and morphological approach, we present an intensive evaluation of microbial eukaryote communities prior to and following oiling around heavily impacted shorelines. Our results show significant changes in community structure, with pre-spill assemblages of diverse Metazoa giving way to dominant fungal communities in post-spill sediments. Post-spill fungal taxa exhibit low richness and are characterized by an abundance of known hydrocarbon-degrading genera, compared to prior communities that contained smaller and more diverse fungal assemblages. Comparative taxonomic data from nematodes further suggests drastic impacts; while pre-spill samples exhibit high richness and evenness of genera, post-spill communities contain mainly predatory and scavenger taxa alongside an abundance of juveniles. Based on this community analysis, our data suggest considerable (hidden) initial impacts across Gulf beaches may be ongoing, despite the disappearance of visible surface oil in the region

Serum IGF-1 Affects Skeletal Acquisition in a Temporal and Compartment-Specific Manner

Insulin-like growth factor-1 (IGF-1) plays a critical role in the development of the growing skeleton by establishing both longitudinal and transverse bone accrual. IGF-1 has also been implicated in the maintenance of bone mass during late adulthood and aging, as decreases in serum IGF-1 levels appear to correlate with decreases in bone mineral density (BMD). Although informative, mouse models to date have been unable to separate the temporal effects of IGF-1 depletion on skeletal development. To address this problem, we performed a skeletal characterization of the inducible LID mouse (iLID), in which serum IGF-1 levels are depleted at selected ages. We found that depletion of serum IGF-1 in male iLID mice prior to adulthood (4 weeks) decreased trabecular bone architecture and significantly reduced transverse cortical bone properties (Ct.Ar, Ct.Th) by 16 weeks (adulthood). Likewise, depletion of serum IGF-1 in iLID males at 8 weeks of age, resulted in significantly reduced transverse cortical bone properties (Ct.Ar, Ct.Th) by 32 weeks (late adulthood), but had no effect on trabecular bone architecture. In contrast, depletion of serum IGF-1 after peak bone acquisition (at 16 weeks) resulted in enhancement of trabecular bone architecture, but no significant changes in cortical bone properties by 32 weeks as compared to controls. These results indicate that while serum IGF-1 is essential for bone accrual during the postnatal growth phase, depletion of IGF-1 after peak bone acquisition (16 weeks) is compartment-specific and does not have a detrimental effect on cortical bone mass in the older adult mouse

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Stochastic expansions maintain the clonal stability of CD8+ T cell populations undergoing memory inflation driven by murine cytomegalovirus

CMV is an obligate and persistent intracellular pathogen that continually drives the production of highly differentiated virus-specific CD8+ T cells in an Ag-dependent manner, a phenomenon known as memory inflation. Extensive proliferation is required to generate and maintain inflationary CD8+ T cell populations, which are counterintuitively short-lived and typically exposed to limited amounts of Ag during the chronic phase of infection. An apparent discrepancy therefore exists between the magnitude of expansion and the requirement for ongoing immunogenic stimulation. To address this issue, we explored the clonal dynamics of memory inflation. First, we tracked congenically marked OT-I cell populations in recipient mice infected with murine CMV (MCMV) expressing the cognate Ag OVA. Irrespective of numerical dominance, stochastic expansions were observed in each population, such that dominant and subdominant OT-I cells were maintained at stable frequencies over time. Second, we characterized endogenous CD8+ T cell populations specific for two classic inflationary epitopes, M38 and IE3. Multiple clonotypes simultaneously underwent Ag-driven proliferation during latent infection with MCMV. In addition, the corresponding CD8+ T cell repertoires were stable over time and dominated by persistent clonotypes, many of which also occurred in more than one mouse. Collectively, these data suggest that stochastic encounters with Ag occur frequently enough to maintain oligoclonal populations of inflationary CD8+ T cells, despite intrinsic constraints on epitope display at individual sites of infection with MCMV

A meta-analysis of individual participant data reveals an association between circulating levels of IGF-I and prostate cancer risk

The role of insulin-like growth factors (IGF) in prostate cancer development is not fully understood. To investigate the association between circulating concentrations of IGFs (IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3) and prostate cancer risk, we pooled individual participant data from 17 prospective and two cross-sectional studies, including up to 10,554 prostate cancer cases and 13,618 control participants. Conditional logistic regression was used to estimate the ORs for prostate cancer based on the study-specific fifth of each analyte. Overall, IGF-I, IGF-II, IGFBP-2, and IGFBP-3 concentrations were positively associated with prostate cancer risk (Ptrend all ≤ 0.005), and IGFBP-1 was inversely associated weakly with risk (Ptrend = 0.05). However, heterogeneity between the prospective and cross-sectional studies was evident (Pheterogeneity = 0.03), unless the analyses were restricted to prospective studies (with the exception of IGF-II, Pheterogeneity = 0.02). For prospective studies, the OR for men in the highest versus the lowest fifth of each analyte was 1.29 (95% confidence interval, 1.16-1.43) for IGF-I, 0.81 (0.68-0.96) for IGFBP-1, and 1.25 (1.12-1.40) for IGFBP-3. These associations did not differ significantly by time-to-diagnosis or tumor stage or grade. Aftermutual adjustment for each of the other analytes, only IGF-I remained associated with risk. Our collaborative study represents the largest pooled analysis of the relationship between prostate cancer risk and circulating concentrations of IGF-I, providing strong evidence that IGF-I is highly likely to be involved in prostate cancer development.</p

STARD 2015: An Updated List of Essential Items for Reporting Diagnostic Accuracy Studies.

Incomplete reporting has been identified as a major source of avoidable waste in biomedical research. Essential information is often not provided in study reports, impeding the identification, critical appraisal, and replication of studies. To improve the quality of reporting of diagnostic accuracy studies, the Standards for Reporting of Diagnostic Accuracy Studies (STARD) statement was developed. Here we present STARD 2015, an updated list of 30 essential items that should be included in every report of a diagnostic accuracy study. This update incorporates recent evidence about sources of bias and variability in diagnostic accuracy and is intended to facilitate the use of STARD. As such, STARD 2015 may help to improve completeness and transparency in reporting of diagnostic accuracy studies