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The cilium is a cell surface organelle with unique composition and shape. Although it has now been well appreciated as a signaling compartment for the vertebrate cell, the regulation and function of intraciliary calcium in cilia-mediated signaling are less clear and sometimes controversial. This review focuses on publications regarding calcium in the cilium and the potential interactions between intraciliary calcium and signaling pathways mediated by cilia. Unresolved questions and future directions in the field are also discussed.

The investigation of filtration and loading performance of fibrous filters with different structures is of high importance for designing filters with long lifetime used in applications with high soot concentrations. Penetration of the soot agglomerates and NaCl particles (with the mobility diameters of 50, 80, 100, 200 and 300 nm) through two types of composite filter media (with the nanostructured layer of electrospun nanofibers and PTFE membrane, respectively) was analyzed. Meanwhile, evolution of the experimental and modeled pressure drop during the particles loading process at the velocities of 6.7 and 11.1 cm/s was also studied. The cake thickness was measured by a new and non-contact method utilizing a 3D optical profiler which would not alter the cake structure. The results showed that the soot penetration was lower than that of NaCl particles under the same condition, because the soot agglomerates had larger effective interception length than the NaCl particles with the same mobility diameter. The pressure drop of the filters loaded with soot agglomerates increased faster than that with NaCl particles. Furthermore, the pressure drop increased faster at the velocity of 11.1 cm/s because of formation of more compact cake. In addition, the pressure drop of the filter with a lower solidity nanostructured layer increased slower because more particles could penetrate into its inner part. The model data agreed with the experimental data well in the case of soot loading. Our results indicate that the filters which have relatively low filtration efficiency against the standard compact aerosol particles yet sufficient efficiency against the soot agglomerates and an open structure can be used in the applications with high soot concentrations to gain a long lifetime.

Foxtail millet [Setaria italica (L.) Beauv], an important minor crop in semi-arid regions of Northern China, is valued for its flavor, color and nutrition. In order to understand the relationship between carotenoid accumulation and expression of related genes in foxtail millet, two contrasting varieties were studied. 'Jingu21', which produces yellow millet and 'Zhisheng', white millet, were analyzed for the accumulation and composition of millet carotenoids and for the expression profiles of genes involved in their metabolism.The total yellow pigment content in Jingu21 was 19.23 mg kg−1 due to the high levels of lutein (13.58 mg kg−1) and zeaxathin (3.77 mg kg−1), whereas Zhisheng contained only 2.01 mg kg−1 with 0.81 mg kg−1 lutein and 0.22 mg kg−1 zeaxathin. The expression patterns of 14 carotenoid-related genes at different grain maturing stages indicated that the marked differences in the accumulation of carotenoids in foxtail millet might be explained by the continued up-regulation of SiPSY1 accompanied by the significant down-regulation of SiCCD1 in Jingu21.

bHLH transcription factors play important roles in the abiotic stress response in plants, but their characteristics and functions in Tartary buckwheat (Fagopyrum tataricum), a traditional coarse cereal with a strong stress tolerance, haven't been sufficiently studied. Here, we found that the expression of a bHLH gene, FtbHLH2, was induced significantly by cold treatments in Tartary buckwheat seedlings. Subcellular localization indicated that FtbHLH2 localized in nucleus. Its overexpression in Arabidopsis increased tolerance to cold. The Arabidopsis plants overexpressing FtbHLH2 displayed higher root length and photosynthetic efficiency, and had lower malondialdehyde (MDA) and reactive oxygen species (ROS) after cold treatment compared to wild type (WT) plants. Meanwhile, the expression levels of some stress-related genes in transgenic plants were remarkably higher than that in wild type under normal and/or stress conditions. Furthermore, transgenic Arabidopsis lines with the FtbHLH2 promoter had higher GUS activity after cold stress. On the whole, the results suggest that FtbHLH2 may play a positive regulatory in cold stress of Tartary buckwheat.

Air filtration mechanisms in the composite filter media used in practical applications are important and challenging to understand because the component fibers could have various size scales and morphologies. In this work, a three-dimensional digital model of nanofiber-based filter media was reconstructed for the first time based on the X-ray tomography data for the cellulose substrate and the Focused Ion Beam-Scanning Electron Microscope (FIB-SEM) image analysis for the several micrometers thick (3.82–7.90 μm) electrospun polyvinylidene fluoride (PVDF) nanofiber membrane. Besides the high-resolution model where the details of the fibrous structures were fully resolved, another low-resolution model with approximated unresolved structures was also established. Filtration simulations utilizing these models were conducted considering the drag force, Brownian diffusion and aerodynamic slip. The simulated filtration efficiencies agreed well with the experiments for particles of 70–400 nm, including the most penetrating particle size (MPPS, 100–200 nm). Moreover, the structure-resolved models had higher accuracy but higher computational costs, while the unresolved simulations saved much running time but over-predicted the filtration efficiency, especially for smaller particles (, Journal of Membrane Science, 620, ISSN:0376-7388

Leber congenital amaurosis (LCA) is an early-onset form of retinal degeneration. Six of the 22 known LCA genes encode photoreceptor ciliary proteins. Despite the identification of 22 LCA genes, the genetic basis of ~30% of LCA patients remains unknown. We sought to investigate the cause of disease in the remaining 30% by examining cilia-associated genes. Whole-exome sequencing was performed on an LCA cohort of 212 unsolved probands previously screened for mutations in known retinal-disease genes. Immunohistochemistry using mouse retinas was used to confirm protein localization and zebrafish were used to perform rescue experiments. A homozygous nonsynonymous mutation was found in a single proband in CLUAP1, a gene required for ciliogenesis and cilia maintenance. Cluap1 knockout zebrafish exhibit photoreceptor cell death as early as 5 days after fertilization, and rescue experiments revealed that our proband’s mutation is significantly hypomorphic. Consistent with the knowledge that CLUAP1 plays an important role in cilia function and that cilia are critical to photoreceptor function, our results indicate that hypomorphic mutations in CLUAP1 can result in dysfunctional photoreceptors without systemic abnormalities. This is the first report linking mutations in CLUAP1 to human disease and establishes CLUAP1 as a candidate LCA gene. Genet Med 18 10, 1044–1051.

The bacteria and fungi captured on heat insulating materials or air filter media in the ventilation system in civil flights may reentrant into the indoor air which poses a threat to passengers’ health. The E. coli and B. subtilis bacteria survival rates on the heat insulating blankets typically used as padding materials inside the aircraft walls under the mimicked environmental condition were studied. Then the antibacterial performance of positively charged electret and chitosan modified filter media which can be used in the ventilation systems against E. coli bacteria was investigated. Our results showed that the E. coli survival rate deceased to less than 0.2% and that of the B. subtilis decreased to less than 2.1% of the control samples on the hydrophilic and hydrophobic blankets under the mimic conditions after one flight cycle. The survival rate of E. coli on the positively charged electret filter media decreased to less than 30% compared to the uncharged filter media after six hours due to the disruption of their metabolic balance by the positive charges on the fibers surface. Moreover, the E. coli survival rate on the pure nylon, nylon/chitosan and chitosan dipped nylon-6 nanofibrous filter media decreased to 8.4%, 7.1% and 2.8% after 120 min, respectively. This study sheds light on fabrication of the eco-friendly antibacterial filter materials for the ventilation systems., Building and Environment, 180, ISSN:0360-1323

We demonstrate a new polyvinyl alcohol (PVA)/Lyocell dual-layer (PLD) paper-based separator with high-efficiency and low-cost preparation process as a promising alternative to a commercialized composite separator applied in primary Zinc (Zn)-air batteries. The PLD paper-based separator is fabricated by dual-layer forming papermaking process, composed of PVA fiber layer and Lyocell fibrillated fiber layer. The dual-layer porous structure enables the PLD paper to have submicron-sized pores and good electrolyte retention. More notably, the pore size of the PLD paper can be tuned by controlling the specific surface area of Lyocell fibrillated fiber (herein, 7.1 m2 g−1 and 13.9 m2 g−1 Lyocell fibrillated fibers are exploited). Compared to a PVA/Lyocell monolayer (PLM) paper and a PLD paper containing 7.1 m2 g−1 fibrillated fiber, both a commercialized composite separator and a PLD paper containing 13.9 m2 g−1 fibrillated fiber provide superior discharge and high temperature storage performance.

Our previous study has indicated that prenatal caffeine exposure (PCE) could induce intrauterine growth retardation (IUGR) of offspring. Recent research suggested that IUGR is a risk factor for glomerulosclerosis. However, whether PCE could induce glomerulosclerosis and its underlying mechanisms remain unknown. This study aimed to demonstrate the induction to glomerulosclerosis in adult offspring by PCE and its intrauterine programming mechanisms. A rat model of IUGR was established by PCE, male fetuses and adult offspring at the age of postnatal week 24 were euthanized. The results revealed that the adult offspring kidneys in the PCE group exhibited glomerulosclerosis as well as interstitial fibrosis, accompanied by elevated levels of serum creatinine and urine protein. Renal angiotensin II receptor type 2 (AT2R) gene expression in adult offspring was reduced by PCE, whereas the renal angiotensin II receptor type 1a (AT1aR)/AT2R expression ratio was increased. The fetal kidneys in the PCE group displayed an enlarged Bowman's space and a shrunken glomerular tuft, accompanied by a reduced cortex width and an increase in the nephrogenic zone/cortical zone ratio. Observation by electronic microscope revealed structural damage of podocytes; the reduced expression level of podocyte marker genes, nephrin and podocin, was also detected by q-PCR. Moreover, AT2R gene and protein expressions in fetal kidneys were inhibited by PCE, associated with the repression of the gene expression of glial-cell-line-derived neurotrophic factor (GDNF)/tyrosine kinase receptor (c-Ret) signaling pathway. These results demonstrated that PCE could induce dysplasia of fetal kidneys as well as glomerulosclerosis of adult offspring, and the low functional programming of renal AT2R might mediate the developmental origin of adult glomerulosclerosis.

A four-stage wetland was constructed to improve the water quality and flow pattern of a heavily polluted river in Luzhi Town, a water town in the Taihu Lake region of China. The four-stage constructed wetland system is composed of four interlinked units: a rapid filter, a down-flow subsurface constructed wetland, an up-flow subsurface constructed wetland, and a surface flow constructed wetland. The concentrations of chemical oxygen demand (COD), nitrogen and phosphorus, along the flow path of the constructed wetland, were measured and the pollutant removal efficiencies were calculated. The average removal rate over the whole wetland system was around 60% for COD and total phosphorus (TP), and around 70% for total nitrogen (TN) and ammonia nitrogen (NH 4 + -N). The total annual reduction in COD, TN, NH 4 + -N, and TP by the whole system was about 3.16 t/yr, 0.57 t/yr, 0.13 t/yr, and 0.03 t/yr, respectively. Following treatment of river water via the four-stage constructed wetland system, significant improvements resulted in the water quality and flow pattern of the polluted river.

Urban river restoration is becoming a concern as a result of economic development. One scientific focus is how to restore urban river systems by integrating principles and practices of land use planning, landscaping, aquatic environmental protection, and flood control. A river revitalization project in a historical district in Suzhou City, Jiangsu Province, China is used here as a case study. The study demonstrates the development of a systematic solution that integrated knowledge of urban planning, landscape ecology, environmental science, and hydrology. In accordance with a low impact development (LID) strategy, the planning objectives were designed to give the district the ability to maintain the quantity and quality of the closed scenic water system and to reduce risks of flooding. Low impact development best management practice (LID-BMP) facilities were selected, placed and designed based on landscape planning and the other factors listed above. A model based on the storm water management model (SWMM) was developed to assess the water quantity and quality benefits to be expected by implementing the LID-BMPs under different storm scenarios. Based on an investigation of the pollution sources and the design of the water system, water quantity requirements were then estimated. Deployment of sources for the water system and a water quality maintenance scheme were proposed. In addition, according to the SWMM modeling analysis, although the stormwater pipe system in the district met only the standard required for 2-year recurrence-interval storms, there would be no local flooding in a 5-year recurrence-interval storm, and the local flooding situation would not be serious even when a 20-year recurrence-interval storm occurred.

SummaryMutations in Pkd1, encoding polycystin-1 (PC1), cause autosomal-dominant polycystic kidney disease (ADPKD). We show that the carboxy-terminal tail (CTT) of PC1 is released by γ-secretase-mediated cleavage and regulates the Wnt and CHOP pathways by binding the transcription factors TCF and CHOP, disrupting their interaction with the common transcriptional coactivator p300. Loss of PC1 causes increased proliferation and apoptosis, while reintroducing PC1-CTT into cultured Pkd1 null cells reestablishes normal growth rate, suppresses apoptosis, and prevents cyst formation. Inhibition of γ-secretase activity impairs the ability of PC1 to suppress growth and apoptosis and leads to cyst formation in cultured renal epithelial cells. Expression of the PC1-CTT is sufficient to rescue the dorsal body curvature phenotype in zebrafish embryos resulting from either γ-secretase inhibition or suppression of Pkd1 expression. Thus, γ-secretase-dependent release of the PC1-CTT creates a protein fragment whose expression is sufficient to suppress ADPKD-related phenotypes in vitro and in vivo.

Rad9 is required for the MEC1/TEL1-dependent activation of Saccharomyces cerevisiae DNA damage checkpoint pathways mediated by Rad53 and Chk1. DNA damage induces Rad9 phosphorylation, and Rad53 specifically associates with phosphorylated Rad9. We report here that multiple Mec1/Tel1 consensus [S/T]Q sites within Rad9 are phosphorylated in response to DNA damage. These Rad9 phosphorylation sites are selectively required for activation of the Rad53 branch of the checkpoint pathway. Consistent with the in vivo function in recruiting Rad53, Rad9 phosphopeptides are bound by Rad53 forkhead-associated (FHA) domains in vitro. These data suggest that functionally independent domains within Rad9 regulate Rad53 and Chk1, and support the model that FHA domain-mediated recognition of Rad9 phosphopeptides couples Rad53 to the DNA damage checkpoint pathway.