Human Motion Enhancement via Tobit Kalman Filter-Assisted Autoencoder.

We present a novel approach to enhance the quality of human motion data collected by low-cost depth sensors, namely D-Mocap, which suffers from low accuracy and poor stability due to occlusion, interference, and algorithmic limitations. Our approach takes advantage of a large set of high-quality and diverse Mocap data by learning a general motion manifold via the convolutional autoencoder. In addition, the Tobit Kalman filter (TKF) is used to capture the kinematics of each body joint and handle censored measurement distribution. The TKF is incorporated with the autoencoder via latent space optimization, maintaining adherence to the motion manifold while preserving the kinematic nature of the original motion data. Furthermore, due to the lack of an open source benchmark dataset for this research, we have developed an extension of the Berkeley Multimodal Human Action Database (MHAD) by generating D-Mocap data from RGB-D images. The newly extended MHAD dataset is skeleton-matched and time-synced to the corresponding Mocap data and is publicly available. Along with simulated D-Mocap data generated from the CMU Mocap dataset and our self-collected D-Mocap dataset, the proposed algorithm is thoroughly evaluated and compared with different settings. Experimental results show that our approach can improve the accuracy of joint positions and angles as well as skeletal bone lengths by over 50%.

[Effects of ginkgolide B on arachidonic acid metabolizing enzymes and level of intracellular calcium in rat polymorphonuclear leukocytes].

AIM: To investigate the effects of ginkgolide B on arachidonic acid (AA) metabolizing enzymes and the level of intracellular calcium in rat polymorphonuclear leukocytes. METHODS: Intracellular free calcium was quantitated by Fura-2 fluorescence technique. Phospholipase A2 (PLA2) activity was determined by incorporating 3H-arachidonic acid in leukocytes. 5-Lipoxygenase (5-LO) activity was evaluated by RP-HPLC. RESULTS: In comparison with control, ginkgolide B at final concentration of 0.1-10 mumol.L-1 inhibited A23187 induced AA release by 10.9%-22.2%; at final concentration of 0.1-50 mumol.L-1, ginkgolide B inhibited LTB4 and 5-HETE synthesis stimulated by PAF by 29.4%-88.8% and 26.2%-89.3% respectively. At the final concentration of 0.1-100 mumol.L-1, ginkgolide B decreased the rise of intracellular calcium level induced by pletelet activating factor (PAF) and N-formyl-methionine-leucine-phenglalanine (fMLP) by 13.9%-51.4% and 2.2%-36.6%, respectively. CONCLUSION: Ginkgolide B was found to significantly inhibit PLA2 and 5-LO activities, as well as the increase of the intracellular calcium induced by PAF.

[Effects of musk glucoprotein on PAF production and cytosolic Ca2+ level in rat polymorphonuclear leukocytes in vitro].

OBJECTIVE: To investigate the effects of Musk glucoprotein on platelet activating factor (PAF) production and the concentration of cytosolic free Ca2+ in polymorphonuclear leukocytes of rat. METHODS: An in vitro incubation system was used, production of PAF and activity of acetyl transferase were measured by isotope incorporation, the concentration of cytosolic free Ca2+ was quantitated using the fluorescent Ca2+ indicator Fura-2. RESULTS: Musk-1 at concentration of 1-100 micrograms.ml-1 can significantly inhibit production of PAF, activity of acetyl transferase and the increase of cytosolic Ca2+ concentration in polymorphonuclear leukocytes of rat. CONCLUSION: Part of mechanisms underlying antiinflammatory action of Musk-1 is through inhibiting the synthesis of PAF and the increase of cytosolic Ca2+ level.

[Effects of a novel antiprogestin derivative ZXH951 on proliferation and telomerase activity of human breast carcinoma cell lines].

AIM: To investigate the antiproliferative activity of a new synthetic steroid ZXH951 structurally related to mifepristone (RU486) and its effects on cell cycle traverse and telomerase activity in human breast carcinoma cell lines. METHODS: Antiproliferative activity was determined by cell growth curve, MTT reduction and colony formation. Receptor binding affinities were measured by competitive binding assay using radiolabelled ligands. Cell cycle distribution was analyzed by flow cytometry. Telomerase activity was investigated by TRAP-PCR. RESULTS: ZXH951 exhibited potent antiproliferative activity in estrogen receptor and progesterone receptor positive human breast carcinoma cell lines in vitro, high affinity with human progesterone receptor-A, little affinity with estrogen receptor and blockade the cells in G1 phase. Moreover, when T47D cells were exposed to 0.4, 1.0 and 10 mumol.L-1 of ZXH951 for 72 h, the telomerase activity was significantly decreased. CONCLUSION: ZXH951 is a promising progesterone receptor antagonist. It significantly inhibits the growth of estrogen receptor and progesterone receptor positive human breast carcinoma cells. Its mechanism of action may be related to its antiproliferation mediated by progesterone receptor and inhibition of telomerase activity.

Calamistrins A and B, two new cytotoxic monotetrahydrofuran annonaceous acetogenins from Uvaria calamistrata.

Two new bioactive monotetrahydrofuran acetogenins, calamistrins A (1) and B (2), and two known compounds, uvarigrin (3) and uvarigranin (4), have been isolated from the roots of Uvaria calamistrata. The structures of the new compounds were elucidated by spectroscopic and chemical methods. The absolute stereochemistry of the stereogenic centers was established by Mosher ester methodology.