42 research outputs found
Split, Merge, and Refine: Fitting Tight Bounding Boxes via Learned Over-Segmentation and Iterative Search
We present a novel framework for finding a set of tight bounding boxes of a
3D shape via neural-network-based over-segmentation and iterative merging and
refinement. Achieving tight bounding boxes of a shape while guaranteeing the
complete boundness is an essential task for efficient geometric operations and
unsupervised semantic part detection, but previous methods fail to achieve both
full coverage and tightness. Neural-network-based methods are not suitable for
these goals due to the non-differentiability of the objective, and also classic
iterative search methods suffer from their sensitivity to the initialization.
We demonstrate that the best integration of the learning-based and iterative
search methods can achieve the bounding boxes with both properties. We employ
an existing unsupervised segmentation network to split the shape and obtain
over-segmentation. Then, we apply hierarchical merging with our novel
tightness-aware merging and stopping criteria. To overcome the sensitivity to
the initialization, we also refine the bounding box parameters in a game setup
with a soft reward function promoting a wider exploration. Lastly, we further
improve the bounding boxes with a MCTS-based multi-action space exploration.
Our experimental results demonstrate the full coverage, tightness, and the
adequate number of bounding boxes of our method
INO80 function is required for mouse mammary gland development, but mutation alone may be insufficient for breast cancer
The aberrant function of ATP-dependent chromatin remodeler INO80 has been implicated in multiple types of cancers by altering chromatin architecture and gene expression; however, the underlying mechanism of the functional involvement of INO80 mutation in cancer etiology, especially in breast cancer, remains unclear. In the present study, we have performed a weighted gene co-expression network analysis (WCGNA) to investigate links between INO80 expression and breast cancer sub-classification and progression. Our analysis revealed that INO80 repression is associated with differential responsiveness of estrogen receptors (ERs) depending upon breast cancer subtype, ER networks, and increased risk of breast carcinogenesis. To determine whether INO80 loss induces breast tumors, a conditional INO80-knockout (INO80 cKO) mouse model was generated using the Cre-loxP system. Phenotypic characterization revealed that INO80 cKO led to reduced branching and length of the mammary ducts at all stages. However, the INO80 cKO mouse model had unaltered lumen morphology and failed to spontaneously induce tumorigenesis in mammary gland tissue. Therefore, our study suggests that the aberrant function of INO80 is potentially associated with breast cancer by modulating gene expression. INO80 mutation alone is insufficient for breast tumorigenesis
Generation of homogeneous midbrain organoids with in vivo-like cellular composition facilitates neurotoxin-based Parkinson\u27s disease modeling
Recent studies have demonstrated the generation of midbrain-like organoids (MOs) from human pluripotent stem cells. However, the low efficiency of MO generation and the relatively immature and heterogeneous structures of the MOs hinder the translation of these organoids from the bench to the clinic. Here we describe the robust generation of MOs with homogeneous distribution of midbrain dopaminergic (mDA) neurons. Our MOs contain not only mDA neurons but also other neuronal subtypes as well as functional glial cells including astrocytes and oligodendrocytes. Furthermore, our MOs exhibit mDA neuron-specific cell death upon treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, indicating that MOs could be a proper human model system for studying the in vivo pathology of Parkinson\u27s disease (PD). Our optimized conditions for producing homogeneous and mature MOs might provide an advanced patient-specific platform for in vitro disease modeling as well as for drug screening for PD