Convex Dual Theory Analysis of Two-Layer Convolutional Neural Networks With Soft-Thresholding.

Soft-thresholding has been widely used in neural networks. Its basic network structure is a two-layer convolution neural network with soft-thresholding. Due to the network's nature of nonlinear and nonconvex, the training process heavily depends on an appropriate initialization of network parameters, resulting in the difficulty of obtaining a globally optimal solution. To address this issue, a convex dual network is designed here. We theoretically analyze the network convexity and prove that the strong duality holds. Extensive results on both simulation and real-world datasets show that strong duality holds, the dual network does not depend on initialization and optimizer, and enables faster convergence than the state-of-the-art two-layer network. This work provides a new way to convexify soft-thresholding neural networks. Furthermore, the convex dual network model of a deep soft-thresholding network with a parallel structure is deduced.

Construction of carboxymethyl chitosan-based nanoparticles of hypoxia response for co-loading doxorubicin and tanshinone IIA.

As a first-line drug for breast cancer chemotherapy, the effectiveness of doxorubicin (DOX) is challenged by high doses and high toxicity. Studies showed the combination of Tanshinone IIA (TSIIA) and DOX could enhance the efficacy of DOX for cancer and reduce the toxic effects to normal tissues. Unfortunately, free drugs are easily metabolized in the systemic circulation, which are less prone to aggregation at the tumor site to exert anticancer efficacy. In present study, we prepared a carboxymethyl chitosan-based hypoxia-responsive nanoparticles loaded with DOX and TSIIA for the treatment of breast cancer. The results demonstrated that these hypoxia-responsive nanoparticles not only improved the delivery efficiency of the drugs but also enhanced the therapeutic efficacy of DOX. The average size of nanoparticles was about 200-220 nm, the optimal drug loading and encapsulation efficiency of TSIIA in DOX/TSIIA NPs were 9.06 % and 73.59 %, respectively. Hypoxia-responsive behavior were recorded in vitro, while the synergistic efficacy is significantly exhibited in vivo and the tumor inhibitory rate was 85.87 %. Notably, TUNEL assay and immunofluorescence staining verified that the combined nanoparticles exerted a synergistic anti-tumor effect by inhibiting tumor fibrosis, decreasing the expression of HIF-1α and inducing tumor cell apoptosis. Collectively, this carboxymethyl chitosan-based hypoxia-responsive nanoparticles could have promising application prospect for effective breast cancer therapy.

Probiotic-Functionalized Silk Fibroin/Sodium Alginate Scaffolds with Endoplasmic Reticulum Stress-Relieving Properties for Promoted Scarless Wound Healing.

Bioactive substances such as probiotics are becoming a research hotspot in the field of tissue regeneration due to their excellent regulatory functions. Here, we proposed to load Lactobacillus casei onto a bilayer silk fibroin/sodium alginate (SF/SA) scaffold to endow the scaffold with both antibacterial and regenerative properties. The performance of the scaffold was characterized systemically. The L. casei-loaded scaffolds (L-SF/SA) bring in lactic acid, which has antibacterial and wound healing properties. In vitro, the cell-free supernatant (CFS) of L. casei inhibited the transformation of fibroblasts to myofibroblasts and relieved the endoplasmic reticulum stress (ERS). In vivo, L-SF/SA accelerated the healing of infected wounds in SD rats. The L-SF/SA reduced the bacterial load, induced M2 polarization of macrophages, increased angiogenesis, regulated collagen ratio, and alleviated the ERS, thereby promoting scarless wound healing and increasing hair follicle regeneration. Therefore, probiotic-functionalized silk fibroin/alginate scaffolds showed potential in the infected wound healing.

A glutathione-sensitive drug delivery system based on carboxymethyl chitosan co-deliver Rose Bengal and oxymatrine for combined cancer treatment.

At present, monotherapy of tumor has not met the clinical needs, due to high doses, poor efficacy, and the emergence of drug resistance. Combination therapy can effectively solve these problems, which is a better option for tumor suppression. Based on this, we developed a novel glutathione-sensitive drug delivery nanoparticle system (OMT/CMCS-CYS-RB NPs) for oral cancer treatment. Briefly, carboxymethyl chitosan (CMCS) was used as a carrier to simultaneously load Rose Bengal (RB) and oxymatrine (OMT). The OMT/CMCS-CYS-RB NPs prepared by ion crosslinking were spheres with a stable structure. In addition, the nanoparticles can be excited in vitro to generate a large amount of singlet oxygen, which has a good photodynamic effect. In vitro anti-tumor activity study showed that the nanoparticles after the laser enhanced therapeutic efficacy on tumor cells compared with the free drug and exhibited well security. Furthermore, OMT/CMCS-CYS-RB NPs could inhibit the PI3K/AKT signaling pathway in oxidative stress, and realize tumor apoptosis through mitochondria-related pathways. In conclusion, this combination delivery system for delivering RB and OMT is a safe and effective strategy, which may provide a new avenue for the tumor treatment.

Structural Color Controllable Humidity Response Chiral Nematic Cellulose Nanocrystalline Film.

Through self-assembly, environmentally friendly cellulose nanocrystals (CNCs) can form films with a photonic crystal structure whose pitch size can be adjusted in a variety of ways at the fabrication stage. Moreover, the films exhibit response performance to multiple stimuli, which offers extensive applications. Poly(ethylene glycol) (PEG) and CNCs combine to form a smaller chiral nematic domain that develops a solid film with a uniform spiral structure when slowly dried. By changing the composition of CNCs and PEG, flexible and flat photonic composite films with uniform structural colors from blue to red are prepared. Benefiting from the change in pitch size by insertion and detachment of water molecules into the chiral nematic structure, CNCs films and CNC-PEG composite films exhibit a reversible structural color change in response to different humidity. In addition, the chiral nematic films formed by the combination of glycerol and CNCs have a reversible stimulation response to hydrochloric acid gas. Similarly, adjusting the ratio of glycerol can control the pitch size of the films and, thus, the reflective color. In summary, the pitch size of the photonic crystal structure of the films can be precisely tuned by regulating the additive ratio, and the two prepared films have reversible responses to humidity and hydrochloric acid gas, respectively. The CNC-based films show promise in the application of colorimetric biosensors.

Glutathione-sensitive IPI-549 nanoparticles synergized with photodynamic Chlorin e6 for the treatment of breast cancer.

We combined phosphoinositol-3-kinin inhibitor IPI-549 and photodynamic Chlorin e6 (Ce6) on carboxymethyl chitosan to develop a novel drug delivery nanoparticle (NP) system (Ce6/CMCS-DSP-IPI549) and evaluate its glutathione (GSH) sensitivity and targeting ability for breast cancer treatment. The NPs were spherical with a uniform size of 218.8 nm, a stable structure over 7 days. The maximum encapsulation efficiency was 64.42%, and NPs drug loading was 8.05%. The NPs released drugs within tumor cells due to their high GSH concentration, while they maintained structural integrity in normal cells, which have low GSH concentration. The cumulative release rates of IPI-549 and Ce6 at 108 h were 70.67% and 40.35% (at GSH 10 mM) and 8.11% and 2.71% (at GSH 2µM), respectively. The NPs showed a strong inhibitory effect on 4T1 cells yet did not affect human umbilical vein endothelial cells (HUVECs). After irradiation by a 660 nm infrared laser for 72 h, the survival rate of 4T1 cells was 15.51%. Cellular uptake studies indicated that the NPs could accurately release drugs into tumor cells. In addition, the NPs had a good photodynamic effect and promoted the release of reactive oxygen species to damage tumor cells. Overall, the combination therapy of IPI-549 and Ce6 is safe and effective, and may provide a new avenue for the treatment of breast cancer.

InP/ZnS quantum dots doped blue phase liquid crystal with wide temperature range and low driving voltage.

Blue-phase liquid crystals (BPLCs) are regarded as potential materials for the exploitation of next-generation optical devices due to the rapid response, wide viewing angle, and simple industrial production procedures. However, practical application of traditional BPLCs is limited by their narrow temperature range and high driving voltage. Herein, we demonstrated that doping of chiral molecular isosorbide hexyloxybenzoate (R811) into BPLCs is able to increase the temperature range. More importantly, addition of InP/ZnS quantum dots (QDs) with oleylamine surface groups could also effectively broaden the temperature range of the BPLCs further while decreasing the driving voltage, which is attributed to the quantum dot trapped by BPLCs lattice defect that reduces its free energy. Since the trapped quantum dot subsequently forms a local electric field under electric field, the effective electric field of the surrounding liquid crystal molecules is enhanced and the rotation of the liquid crystal molecules is accelerated. Specially, the temperature range is widened by 1.4 °C, and the driving voltage is reduced by 57%, under the optimal concentration of R811 and lnP/ZnS QDs. The accomplishment we proposed in this work is a prospective optimization which makes the practical application of blue phase liquid crystals one step closer.

Performance Characteristics and Clinical Value of the Lipoprotein-Associated Phospholipase A2 by an Enzymatic Kinetic Method.

OBJECTIVE: To analyze the performance characteristics, stability, and clinical value of lipoprotein-associated phospholipase A2 (Lp-PLA2) using an enzymatic kinetic method. METHODS: The performance characteristics included reference intervals, precision, and accuracy. We assessed Lp-PLA2 stability by comparing Lp-PLA2 changes under different conditions. Lp-PLA2 was determined in the following groups: control individuals, patients with coronary heart disease (CHD), patients of different lipid subgroups within CHD, and patients with high total cholesterol (TC). Also, correlations between Lp-PLA2 and traditional cardiovascular risk factors were assessed. RESULTS: The mean (SD) reference interval of serum Lp-PLA2 activity was 451 (113) U per L with sex differences. Inter- and intra-assay precision revealed coefficients of variance (CVs) of 1.81% to 2.63% and 1.43% to 1.77%. The average bias was 0.33%. Lp-PLA2 activity was stable. In the CHD group, high-lipid subgroups, and high-TC group, Lp-PLA2 was elevated, and correlation was observed between Lp-PLA2 and traditional risk factors. CONCLUSION: Lp-PLA2 activity has important clinical value in CHD.