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The seasonal and regional variations of cloud fractions are compared across two generations of global climate model ensembles, specifically, the Coupled Model Intercomparison Project-5 (CMIP5) and CMIP6, through the historical period in terms of skills and multimodel agreement. We find a wider spread of historical cloud fraction changes in the CMIP6 than was simulated by the CMIP5. The global mean cloud fractions of CMIP6 increased by about 4.5% from the CMIP5, which attributed to greater changes in the northern hemisphere than in the southern hemisphere. The CMIP6 cloud fractions in recent years are validated with the CALIPSO_CLOUSAT observations to understand the cloud fraction uncertainties in CMIP6 models. The CMIP6 ensemble mean of cloud fractions compares well with the observations with a mean difference of 0.5% in lower altitudes. The CMIP6 cloud fractions are higher than the observations at higher latitudes in both hemispheres in the upper troposphere, and the biases vary from one model to another. The spatial difference between the ensemble and observations is further revealed over the tropics: where the model displays a 3% higher bias. In addition, we observed a significant trend occuring in the northern hemisphere since the mid-20th century using calculations of cloud fraction trends based on the robust regression technique. Finally, we reduce the differences between the model and observations by applying a simple regression technique. The results exemplify that the model and modified observations compare well, with the root mean square value decreased by nearly 28%, and the correlation increased significantly. ©2020. The Authors.

PurposeThe application of induced pluripotent stem cell-derived retinal pigmented epithelium (iPSC-RPE) in patients with retinal degenerative disease is making headway toward the clinic, with clinical trials already underway. Multiple groups have developed methods for RPE differentiation from pluripotent cells, but previous studies have shown variability in iPSC propensity to differentiate into RPE.MethodsThis study provides a comparison between 2 different methods for RPE differentiation: (1) a commonly used spontaneous continuously adherent culture (SCAC) protocol and (2) a more rapid, directed differentiation using growth factors. Integration-free iPSC lines were differentiated to RPE, which were characterized with respect to global gene expression, expression of RPE markers, and cellular function.ResultsWe found that all 5 iPSC lines (iPSC-1, iPSC-2, iPSC-3, iPSC-4, and iPSC-12) generated RPE using the directed differentiation protocol; however, 2 of the 5 iPSC lines (iPSC-4 and iPSC-12) did not yield RPE using the SCAC method. Both methods can yield bona fide RPE that expresses signature RPE genes and carry out RPE functions, and are similar, but not identical to fetal RPE. No differences between methods were detected in transcript levels, protein localization, or functional analyses between iPSC-1-RPE, iPSC-2-RPE, and iPSC-3-RPE. Directed iPSC-3-RPE showed enhanced transcript levels of RPE65 compared to directed iPSC-2-RPE and increased BEST1 expression and pigment epithelium-derived factor (PEDF) secretion compared to directed iPSC-1-RPE. In addition, SCAC iPSC-3-RPE secreted more PEDF than SCAC iPSC-1-RPE.ConclusionsThe directed protocol is a more reliable method for differentiating RPE from various pluripotent sources and some iPSC lines are more amenable to RPE differentiation.

PurposeThe application of induced pluripotent stem cell-derived retinal pigmented epithelium (iPSC-RPE) in patients with retinal degenerative disease is making headway toward the clinic, with clinical trials already underway. Multiple groups have developed methods for RPE differentiation from pluripotent cells, but previous studies have shown variability in iPSC propensity to differentiate into RPE.MethodsThis study provides a comparison between 2 different methods for RPE differentiation: (1) a commonly used spontaneous continuously adherent culture (SCAC) protocol and (2) a more rapid, directed differentiation using growth factors. Integration-free iPSC lines were differentiated to RPE, which were characterized with respect to global gene expression, expression of RPE markers, and cellular function.ResultsWe found that all 5 iPSC lines (iPSC-1, iPSC-2, iPSC-3, iPSC-4, and iPSC-12) generated RPE using the directed differentiation protocol; however, 2 of the 5 iPSC lines (iPSC-4 and iPSC-12) did not yield RPE using the SCAC method. Both methods can yield bona fide RPE that expresses signature RPE genes and carry out RPE functions, and are similar, but not identical to fetal RPE. No differences between methods were detected in transcript levels, protein localization, or functional analyses between iPSC-1-RPE, iPSC-2-RPE, and iPSC-3-RPE. Directed iPSC-3-RPE showed enhanced transcript levels of RPE65 compared to directed iPSC-2-RPE and increased BEST1 expression and pigment epithelium-derived factor (PEDF) secretion compared to directed iPSC-1-RPE. In addition, SCAC iPSC-3-RPE secreted more PEDF than SCAC iPSC-1-RPE.ConclusionsThe directed protocol is a more reliable method for differentiating RPE from various pluripotent sources and some iPSC lines are more amenable to RPE differentiation.

Kawasaki disease (KD) is a childhood vasculitis and the most frequent cause of paediatric acquired heart disease in North America, Europe and Japan. It is increasingly recognised in rapidly industrialising countries such as China and India where it may replace rheumatic heart disease as the most common cause of acquired heart disease in children. We review the current global epidemiology of KD and discuss some public health implications.

Kawasaki disease (KD) is a childhood vasculitis and the most frequent cause of paediatric acquired heart disease in North America, Europe and Japan. It is increasingly recognised in rapidly industrialising countries such as China and India where it may replace rheumatic heart disease as the most common cause of acquired heart disease in children. We review the current global epidemiology of KD and discuss some public health implications.