IC neuron: An efficient unit to construct neural networks.

As a popular machine learning method, neural networks can be used to solve many complex tasks. Their strong generalization ability comes from the representation ability of the basic neuron models. The most popular neuron model is the McCulloch-Pitts (MP) neuron, which uses a simple transformation to process the input signal. A common trend is to use the MP neuron to design various neural networks. However, the optimization of the neuron structure is rarely considered. Inspired by the elastic collision model in physics, we propose a new neuron model that can represent more complex distributions. We term it the Inter-layer Collision (IC) neuron which divides the input space into multiple subspaces to represent different linear transformations. Through this operation, the IC neuron enhances the non-linear representation ability and emphasizes useful input features for a given task. We build the IC networks by integrating the IC neurons into the fully-connected, the convolutional, and the recurrent structures. The IC networks outperform the traditional neural networks in a wide range of tasks. Besides, we combine the IC neuron with deep learning models and show the superiority of the IC neuron. Our research proves that the IC neuron can be an effective basic unit to build network structures and make the network performance better.

Antitumor effects of brucine immuno-nanoparticles on hepatocellular carcinoma in vivo.

In vitro and in vivo studies have demonstrated that brucine is able to inhibit the proliferation of liver cancer cells and growth of animal tumors, and may be a promising anticancer drug. However, high toxicity, poor water solubility, short half-life, narrow therapeutic window, and similar therapeutic and toxic doses limit its clinical application in the treatment of malignant tumors. In our previous study, brucine immuno-nanoparticles were successfully prepared and added to the culture medium of liver cancer SMMC-7721 cells, and the results indicated that the brucine immuno-nanoparticles were able to target the cell membrane of liver cancer SMMC-7721 cells and significantly inhibit the proliferation, adhesion, invasion and metastasis of SMMC-7721 cells. The aim of the present study was to investigate the antitumor effect of brucine immuno-nanoparticles in vivo by establishing an in situ transplanted liver cancer in nude mice. The results indicated that in vivo application of the brucine immuno-nanoparticles resulted in temporary liver and kidney damage, and significantly reduced the α-fetoprotein (AFP) secretion of tumor cells (Bru-NP-MAb vs. the other groups; P<0.05). The brucine concentration of tumor tissues in the brucine immuno-nanoparticles group was significantly increased compared with that of the brucine nanoparticles group (Bru-NP-MAb vs. Bru-NP group or brucine group; P<0.05). The brucine immuno-nanoparticles were able to inhibit tumor growth and cluster of differentiation 34 expression and angiogenesis of tumor tissues, and induce the apoptosis of tumor cells (Bru-NP-MAb vs. Bru-NP group or brucine group; P<0.05). In conclusion, as a novel type of targeted drug, brucine nanoparticles combined with anti-AFP monoclonal antibodies was more effective compared with brucine nanoparticles or brucine alone in inhibiting tumor growth via the enhancement of apoptosis, and the suppression of proliferation and angiogenesis in vivo. Therefore, the brucine immuno-nanoparticle is a promising targeted drug for the treatment of hepatocellular carcinoma.

Influence of particle size on transport of methotrexate across blood brain barrier by polysorbate 80-coated polybutylcyanoacrylate nanoparticles.

Transports of methotrexate-loaded polybutylcyanoacrylate nanoparticles with different sizes across blood brain barrier were investigated in this experiment. The drug-loaded nanoparticles were prepared by emulsion polymerization method. After coating with polysorbate 80, nanoparticles with the size 70, 170, 220, 345 nm were, respectively, i.v. injected into rats at the dose of 3.2 mg/kg. Uncoated nanoparticles and methotrexate solution were also i.v. injected at the same dosage as controls. 0.5, 1, 1.5, 2, 3, 4 h after injection, cerebrospinal fluids and brain tissues were collected for tests. Drug level in all biological samples was determined by HPLC. It was found out that nanoparticles overcoated by polysorbate 80 could significantly improve the drug level in both brain tissues and cerebrospinal fluids compared with uncoated ones and simple solution. Seventy-nanometer nanoparticles could deliver more drugs into brain while no significant difference was observed among the other three size ranges. In conclusion, polysorbate 80-coated polybutylcyanoacrylate nanoparticles could be used to overcome blood brain barrier especially those whose diameter was below 100 nm.

Effects of intranasal administration of nimodipine on cerebral hemodynamics of dogs.

AIM: To investigate the effect of nimodipine (NM) on cerebral blood flow (CBF) in dogs following intranasal administration. METHODS: NM solution was administered intranasally, intravenously (i.v.), and orally to dogs and the change of CBF was determined by using electromagnetic blood flowmeter. MFLab experimental program was applied to monitor the experimental process and analyze data. RESULTS: CBF markedly increased after iv and intranasal application, while large variance was observed after oral dosing. CBF in dogs after three administrations increased by 26.4%, 28.0% and 8.5%, respectively, compared with that of baseline. Following intranasal administration, the onset of action was slightly slower than that after iv injection [(5 +/- 4) min vs (2.2 +/- 1.2) min], however the duration of improvement was the longest [ (25 +/- 17) min]. CONCLUSION: Intranasal delivery for NM can be a promising alternative to parenteral or oral administration.

Anti-tumor effects of brucine immuno-nanoparticles on hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma is difficult to diagnose early, and most patients are already in the late stages of the disease when they are admitted to hospital. The total 5-year survival rate is less than 5%. Recent studies have showed that brucine has a good anti-tumor effect, but high toxicity, poor water solubility, short half-life, narrow therapeutic window, and a toxic dose that is close to the therapeutic dose, which all limit its clinical application. This study evaluated the effects of brucine immuno-nanoparticles (BIN) on hepatocellular carcinoma. MATERIALS AND METHODS: Anionic polymerization, chemical modification technology, and phacoemulsification technology were used to prepare a carboxylated polyethylene glycol-polylactic acid copolymer carrier material. Chemical coupling technology was utilized to develop antihuman AFP McAb-polyethylene glycol-polylactic acid copolymer BIN. The size, shape, zeta potential, drug loading, encapsulation efficiency, and release of these immune-nanoparticles were studied in vitro. The targeting, and growth, invasion, and metastasis inhibitory effects of this treatment on liver cancer SMMC-7721 cells were tested. RESULTS: BIN were of uniform size with an average particle size of 249 ± 77 nm and zeta potential of -18.7 ± 4.19 mV. The encapsulation efficiency was 76.0% ± 2.3% and the drug load was 5.6% ± 0.2%. Complete uptake and even distribution around the liver cancer cell membrane were observed. CONCLUSION: BIN had even size distribution, was stable, and had a slow-releasing effect. BIN targeted the cell membrane of the liver cancer cell SMMC-7721 and significantly inhibited the growth, adhesion, invasion, and metastasis of SMMC-7721 cells. As a novel drug carrier system, BIN are a potentially promising targeting treatment for liver cancer.