Subsurface scattering in point-based rendering

The Department of Computer Engineering, Sejong University in Korea and ETH Zurich in Switzerland have recently introduced a novel and simple framework for rendering subsurface scattering on surfaces represented by points. This is useful for realistically rendering a cloud of points representing translucent materials such as the human skin. This significant study is reported in Vol. 53, No. 5 of SCIENCE CHINA Information Sciences.
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Genome-wide association study identifies susceptibility loci for IgA nephropathy

We carried out a genome-wide association study of IgA nephropathy, a major cause of kidney failure worldwide. We studied 1,194 cases and 902 controls of Chinese Han ancestry, with targeted follow up in Chinese and European cohorts comprising 1,950 cases and 1,920 controls. We identified three independent loci in the major histocompatibility complex, as well as a common deletion of CFHR1 and CFHR3 at chromosome 1q32 and a locus at chromosome 22q12 that each surpassed genome-wide significance (P values for association between 1.59 × 10?2? and 4.84 × 10?? and minor allele odds ratios of 0.63-0.80). These five loci explain 4-7% of the disease variance and up to a tenfold variation in interindividual risk. Many of the alleles that protect against IgA nephropathy impart increased risk for other autoimmune or infectious diseases, and IgA nephropathy risk allele frequencies closely parallel the variation in disease prevalence among Asian, European and African populations, suggesting complex selective pressures.     

Genetics of early mammalian folliculogenesis

Early ovarian folliculogenesis begins with the breakdown of germ cell clusters and formation of primordial follicles. Primordial follicles are the smallest ovarian follicle units continuously recruited to grow into primary and more advanced ovarian follicles. Genes expressed in the germ cells such as Figla, Nobox, Kit and Ntrk2, as well as genes expressed in the surrounding somatic cells such as Foxl2, Kitl and Ngf, play critical functions during early folliculogenesis. Transgenic mice continue to provide important insights into the genetic pathways that regulate early mammalian folliculogenesis. Genes critical in early folliculogenesis are important determinants of reproductive life span and represent candidate genes for human ovarian failure. Received 25 August 2005; received after revision 18 October 2005; accepted 21 November 2005     

α-Synuclein occurs physiologically as a helically folded tetramer that resists aggregation

Parkinson's disease is the second most common neurodegenerative disorder. Growing evidence indicates a causative role of misfolded forms of the protein α-synuclein in the pathogenesis of Parkinson's disease. Intraneuronal aggregates of α-synuclein occur in Lewy bodies and Lewy neurites, the cytopathological hallmarks of Parkinson's disease and related disorders called synucleinopathies. α-Synuclein has long been defined as a 'natively unfolded' monomer of about 14?kDa (ref. 6) that is believed to acquire α-helical secondary structure only upon binding to lipid vesicles. This concept derives from the widespread use of recombinant bacterial expression protocols for in vitro studies, and of overexpression, sample heating and/or denaturing gels for cell culture and tissue studies. In contrast, we report that endogenous α-synuclein isolated and analysed under non-denaturing conditions from neuronal and non-neuronal cell lines, brain tissue and living human cells occurs in large part as a folded tetramer of about 58?kDa. Several methods, including analytical ultracentrifugation, scanning transmission electron microscopy and in vitro cell crosslinking confirmed the occurrence of the tetramer. Native, cell-derived α-synuclein showed α-helical structure without lipid addition and had much greater lipid-binding capacity than the recombinant α-synuclein studied heretofore. Whereas recombinantly expressed monomers readily aggregated into amyloid-like fibrils in vitro, native human tetramers underwent little or no amyloid-like aggregation. On the basis of these findings, we propose that destabilization of the helically folded tetramer precedes α-synuclein misfolding and aggregation in Parkinson's disease and other human synucleinopathies, and that small molecules that stabilize the physiological tetramer could reduce α-synuclein pathogenicity.     

Bacterial peptide deformylase inhibitor PMT analogs inhibit cancer cell growth by interacting with human peptide deformylase

Potent inhibitors of human peptide deformylase （HsPDF） were screened using known PMT analog inhibi- tors of bacterial peptide deformylase. Forty-three species of PMT analogs that are non-peptidyl bacterial PDF inhibitors like actinonin were selected using virtual screening GOLD. Ten species out of 43 that could bind to HsPDF were selected and their antitumor activities were tested. Among them, four species （PMT-172, PMT-173, PMT-199, and PMT-201） showed excellent growth inhibition of cancer cell in the MTT assay. HsPDF-PMT binding was confirmed through a 1H-CPMG-T2 filter NMR experiment leading to a significant change in peak intensity for PMT-172 and PMT-199. These results suggest that PMT analogs could possibly interact with HsPDF and be a novel anticancer drug candidate.     

Models and Algorithm for Stochastic Network Designs

The network design problem (NDP) is one of the most difficult and challenging problems in trans-portation. Traditional NDP models are often posed as a deterministic bilevel program assuming that all relevant inputs are known with certainty. This paper presents three stochastic models for designing transporta-tion networks with demand uncertainty. These three stochastic NDP models were formulated as the expected value model, chance-constrained model, and dependent-chance model in a bilevel programming framew...