Five-year incidence of Nd:YAG laser capsulotomy and association with in vitro proliferation of lens epithelial cells from individual specimens: a case control study

BACKGROUND: The aims of this study were to determine the 5-year incidence of posterior capsule opacification (PCO) requiring Nd:YAG laser capsulotomy in a representative mixed cohort of cataract patients, to determine risk factors for PCO and to investigate possible association with growth of human lens epithelial cells (HLEC) in vitro. METHODS: Pieces of the anterior lens capsule and adhering HLEC were obtained at cataract surgery and cultured individually. After one and two weeks respectively, cultured cells were stained with carboxy-fluorescein diacetate succinimidyl ester (CFDA SE), after which image processing software was used to determine the area of the confluent cell layer. The 5-year incidence of Nd:YAG laser capsulotomy in this cohort was determined through medical records and by mail or telephone interviews. For statistic analyses Mann–Whitney U-test, Fisher’s exact test and binary logistic regression were used. RESULTS: Data on treatment/no treatment for PCO was obtained from 270 patients with a median follow-up time of 57 months (range 50–64 months). The three-year cumulative incidence of PCO was 5.2% and the cumulative 5-year incidence was 11.9%. Patients who had undergone Nd:YAG laser capsulotomy were significantly younger (median 71 years) than patients who did not receive treatment for PCO (median 75 years, p = 0.022). Logistic regression demonstrated that apart from younger age, follow-up time and type of intraocular lens (IOL) were associated with risk of PCO, with hydrophilic 1-piece IOLs conferring a higher risk than hydrophobic acrylic 1-piece or 3-piece IOLs (adjusted OR = 9.4, 95% CI 2.5-35.7, p = 0.001). Of the 270 patients from whom information could be retrieved regarding PCO treatment, in vitro cell culture could be established and quantified from 185 patients. No significant difference in cell growth in vitro was shown between patients subsequently requiring/not requiring Nd:YAG laser capsulotomy. CONCLUSIONS: The cumulative 5-year incidence of 11.9% is comparable or slightly higher than reported in other recent studies. The type of IOL was the most important risk factor for PCO in this study, whereas intrinsic proliferative capacity of the individual’s lens epithelial cells seems to be less important for subsequent PCO development

Guidelines and Recommendations on Yeast Cell Death Nomenclature

Elucidating the biology of yeast in its full complexity has major implications for science, medicine and industry. One of the most critical processes determining yeast life and physiology is cellular demise. However, the investigation of yeast cell death is a relatively young field, and a widely accepted set of concepts and terms is still missing. Here, we propose unified criteria for the definition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death routines that are relevant for the biology of (at least some species of) yeast. As this area of investigation advances rapidly, changes and extensions to this set of recommendations will be implemented in the years to come. Nonetheless, we strongly encourage the authors, reviewers and editors of scientific articles to adopt these collective standards in order to establish an accurate framework for yeast cell death research and, ultimately, to accelerate the progress of this vibrant field of research

Stream dissolved organic matter in permafrost regions shows surprising compositional similarities but negative priming and nutrient effects

Permafrost degradation is delivering bioavailable dissolved organic matter (DOM) and inorganic nutrients to surface water networks. While these permafrost subsidies represent a small portion of total fluvial DOM and nutrient fluxes, they could influence food webs and net ecosystem carbon balance via priming or nutrient effects that destabilize background DOM. We investigated how addition of biolabile carbon (acetate) and inorganic nutrients (nitrogen and phosphorus) affected DOM decomposition with 28-day incubations. We incubated late-summer stream water from 23 locations nested in seven northern or high-altitude regions in Asia, Europe, and North America. DOM loss ranged from 3% to 52%, showing a variety of longitudinal patterns within stream networks. DOM optical properties varied widely, but DOM showed compositional similarity based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. Addition of acetate and nutrients decreased bulk DOM mineralization (i.e., negative priming), with more negative effects on biodegradable DOM but neutral or positive effects on stable DOM. Unexpectedly, acetate and nutrients triggered breakdown of colored DOM (CDOM), with median decreases of 1.6% in the control and 22% in the amended treatment. Additionally, the uptake of added acetate was strongly limited by nutrient availability across sites. These findings suggest that biolabile DOM and nutrients released from degrading permafrost may decrease background DOM mineralization but alter stoichiometry and light conditions in receiving waterbodies. We conclude that priming and nutrient effects are coupled in northern aquatic ecosystems and that quantifying two-way interactions between DOM properties and environmental conditions could resolve conflicting observations about the drivers of DOM in permafrost zone waterways

Guidelines and recommendations on yeast cell death nomenclature

Elucidating the biology of yeast in its full complexity has major implications for science, medicine and industry. One of the most critical processes determining yeast life and physiology is cel-lular demise. However, the investigation of yeast cell death is a relatively young field, and a widely accepted set of concepts and terms is still missing. Here, we propose unified criteria for the defi-nition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differ-ential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death rou-tines that are relevant for the biology of (at least some species of) yeast. As this area of investigation advances rapidly, changes and extensions to this set of recommendations will be implemented in the years to come. Nonetheless, we strongly encourage the au-thors, reviewers and editors of scientific articles to adopt these collective standards in order to establish an accurate framework for yeast cell death research and, ultimately, to accelerate the pro-gress of this vibrant field of research

Le déficit en alpha-1 antitrypsine : modèle d’altération de l’homéostasie protéique ou protéostasie

International audienc

Biological Normalcy

‘Biological normalcy’ refers to relationships between statistical distributions of biological traits (measures of central tendency and variance) and normative views about what bodies ‘should’ be like or what constitutes a ‘normal’ body