Self-Propelled and Near-Infrared-Phototaxic Photosynthetic Bacteria as Photothermal Agents for Hypoxia-Targeted Cancer Therapy.

Hypoxia can increase the resistance of tumor cells to radiotherapy and chemotherapy. However, the dense extracellular matrix, high interstitial fluid pressure, and irregular blood supply often serve as physical barriers to inhibit penetration of drugs or nanodrugs across tumor blood microvessels into hypoxic regions. Therefore, it is of great significance and highly desirable to improve the efficiency of hypoxia-targeted therapy. In this work, living photosynthetic bacteria (PSB) are utilized as hypoxia-targeted carriers for hypoxic tumor therapy due to their near-infrared (NIR) chemotaxis and their physiological characteristics as facultative aerobes. More interestingly, we discovered that PSB can serve as a kind of photothermal agent to generate heat through nonradiative relaxation pathways due to their strong photoabsorption in the NIR region. Therefore, PSB integrate the properties of hypoxia targeting and photothermal therapeutic agents in an "all-in-one" manner, and no postmodification is needed to achieve hypoxia-targeted cancer therapy. Moreover, as natural bacteria, noncytotoxic PSB were found to enhance immune response that induced the infiltration of cytotoxicity T lymphocyte. Our results indicate PSB specifically accumulate in hypoxic tumor regions, and they show a high efficiency in the elimination of cancer cells. This proof of concept may provide a smart therapeutic system in the field of hypoxia-targeted photothermal therapeutic platforms.

[Change laws of water absorption in Chinese herbal pieces and prediction model of relative density for Chinese medicine decoction].

This study aims to explore the change laws of water absorption in Chinese herbal pieces and establish the prediction model of relative density for Chinese medicine compound decoction. Firstly, fitted equations of water absorption and decocting time was established by observing the change laws of water absorption in 36 kinds of Chinese herbal pieces in 12 groups(according to the drug-parts) with decocting time. The r value of the mineral group and other type group was 0.691 2 and 0.663 3, respectively. The r value of the remaining 10 groups was 0.802 2-0.925 4. All P values were less than 0.05(n=21). The formula of the amount of water added was optimized by combining the fitted equations with determined water absorption, and the liquid yield could be controlled in a range of 100%±10%. Secondly, it was determined that the liquid density tester could be used for the rapid determination of relative density of Chinese medicine decoction after methodological study and comparison with the pycnometer method. The linear regression equation between the corrected relative density(y) and extraction ratio(%, x) was built by measuring and analyzing the related parameters such as liquid yield, relative density and extraction ratio in 46 kinds of Chinese herbal pieces. The established equation was y=0.041 3x+1.003 7, r=0.930 9(P <0.01, n=46), with linear range of 1.94%-65.75%. Based on this, the prototype model for predicting relative density of Chinese medicine decoction was established, and the relative densities of 8 Chinese medicine decoctions were within the prediction interval of this model in verification. This study lays a foundation for database construction of Chinese medicine decoction, implementation of personalized decocting mode and rapid quality control of Chinese medicine decoction.

Bone-Targeted Nanoplatform Combining Zoledronate and Photothermal Therapy To Treat Breast Cancer Bone Metastasis.

Bone metastasis, a clinical complication of patients with advanced breast cancer, seriously reduces the quality of life. To avoid destruction of the bone matrix, current treatments focus on inhibiting the cancer cell growth and the osteoclast activity through combination therapy. Therefore, it could be beneficial to develop a bone-targeted drug delivery system to treat bone metastasis. Here, a bone-targeted nanoplatform was developed using gold nanorods enclosed inside mesoporous silica nanoparticles (Au@MSNs) which were then conjugated with zoledronic acid (ZOL). The nanoparticles (Au@MSNs-ZOL) not only showed bone-targeting ability in vivo but also inhibited the formation of osteoclast-like cells and promoted osteoblast differentiation in vitro. The combination of Au@MSNs-ZOL and photothermal therapy (PTT), triggered by near-infrared irradiation, inhibited tumor growth both in vitro and in vivo and relieved pain and bone resorption in vivo by inducing apoptosis in cancer cells and improving the bone microenvironment. This single nanoplatform combines ZOL and PTT to provide an exciting strategy for treating breast cancer bone metastasis.

Multifunctional Magnetic Nanoplatform Eliminates Cancer Stem Cells via Inhibiting the Secretion of Extracellular Heat Shock Protein 90.

Cancer stem cells (CSCs) are responsible for malignant tumor initiation, recurrences, and metastasis. Therefore, targeting CSCs is a promising strategy for the development of cancer therapies. A big challenge for CSC-based cancer therapy is the overexpression of therapeutic stress protein, heat shock protein 90 (Hsp90), which protects CSCs from further therapeutic-induced damage, leading to the failure of treatment. Thus, efficient strategies to target CSCs are urgently needed for cancer therapy. To this end, a multifunctional nanoparticle (MNP) for CSC-based combined thermotherapy and chemotherapy is reported. This strategy dramatically suppresses tumor growth in breast CSC xenograft-bearing mice. Furthermore, a new mechanism is present that the MNP exerts its striking effects on CSCs by inhibiting the secretion of extracellular Hsp90 (eHsp90), resulting in the interruption of several key signaling pathways. These findings open new perspectives on the use of an MNP for effective CSC-based cancer treatment by inhibiting the function of eHsp90.

Leucine-induced promotion of post-absorptive EAA utilization and hepatic gluconeogenesis contributes to protein synthesis in skeletal muscle of dairy calves.

The high rate of protein synthesis in skeletal muscle of dairy calves can benefit their first lactation even lifetime milk yield. Since the rate of protein synthesis is relatively low in the post-absorptive state, the aim of this research was to determine whether leucine supplementation could increase the post-absorptive essential amino acid (EAA) utilization and protein synthesis in the skeletal muscle. Ten male neonatal dairy calves (38 ± 3 kg) were randomly assigned to either the control (CON, no leucine supplementation, n = 5) or supplementation with 1.435 g leucine/L milk (LEU, n = 5). Results showed that leucine significantly increased the length and protein concentration in longissimus dorsi (LD) muscle, whereas it decreased creatinine concentration and glutamic-oxalacetic transaminase (GOT) activity. Compared to the control group, leucine supplementation also reduced the glutamic-pyruvic transaminase (GPT) activity. Supplementation of leucine improved the phosphorylation of mammalian target of rapamycin (mTOR), eukaryotic initiation factor 4E-binding protein 1 (4EBP1) and substrates ribosomal protein S6 kinase 1 (p70S6K). Supplementation of leucine resulted in increased concentrations of glucose, methionine, threonine, histidine and EAAs and decreased concentration of arginine in serum. Liver glucose concentration was higher and pyranic acid was lower in LEU compared to CON. In conclusion, leucine supplementation can promote post-absorptive EAA utilization and hepatic gluconeogenesis, which contributes to protein synthesis in skeletal muscle of dairy calves.

Nucleus-targeted nano delivery system eradicates cancer stem cells by combined thermotherapy and hypoxia-activated chemotherapy.

Many efforts have focused on the cancer stem cell (CSC) targeting nano delivery system, however, the anticancer therapy efficacy is relative low due to the highly drug-resistance and drug efflux. Nucleus-targeted drug delivery is a promising strategy for reverse the drug resistance and drug efflux of CSCs, but in vivo nucleus-targeted drug delivery has been challenging. Herein, we designed a mesoporous silica nanoparticle (MSN)-based nucleus-targeted system, which could directly target the CSCs and further enter the nucleus by the surface modification of anti-CD133 and thermal-triggered exposure of TAT peptides under an alternating magnetic field (AMF). The nucleus-targeted drug release ultimately leads to an exhaustive apoptosis of the CSCs through combined thermotherapy and hypoxia-activated chemotherapy. In vivo, the nucleus-targeted nano delivery system efficiently inhibits the tumor growth without notable side effects during the course of treatment. Molecular mechanism study illustrates that the system effectively eliminates the CSCs by blocking the hypoxia signaling pathway. This designed nucleus-targeted nano delivery system is expected to provide new insights for developing efficient platforms for CSC-targeted cancer therapy.

Porous Organic Polymer-Coated Band-Aids for Phototherapy of Bacteria-Induced Wound Infection.

Band-Aids have been widely used for wound care. For most adhesive bandages, however, they have a limited capacity to speed up the wound healing process, which in turn may cause serious wound infections. In this study, antibacterial Band-Aids, combining porphyrin-based porous organic polymers (POPs) with commercial antibiotic-free Band-Aids, are designed. Under white light irradiation, POPs can produce effective photothermal heat, as well as highly reactive oxygen species (ROS), thereby triggering the potent hyperthermia and simultaneous ROS increase on wounds. Additionally, white light is similar to sunlight, which makes POP-based Band-Aids (PBAs) ideal wound dressings for wound disinfection.

Effects of dietary leucine and phenylalanine on gastrointestinal development and small intestinal enzyme activities in milk-fed holstein dairy calves.

This study was investigated the effects of dietary supplementation of leucine and phenylalanine on the development of the gastrointestinal tract and the intestinal digestive enzyme activity in male Holstein dairy calves. Twenty calves with a body weight of 38 ± 3 kg at 1 day of age were randomly divided into four groups: a control group, a leucine group (1.435 g·l-1), a phenylalanine group (0.725 g·l-1), and a mixed amino acid group (1.435 g·l-1 leucine plus 0.725 g·l-1 phenylalanine). The supplementation of leucine decreased the short-circuit current (Isc) of the rumen and duodenum (P<0.01); phenylalanine did not show any influence on the Isc of rumen and duodenum (P>0.05), and also counteracted the Isc reduction caused by leucine. Leucine increased the trypsin activity at the 20% relative site of the small intestine (P<0.05). There was no difference in the activity of α-amylase and of lactase in the small intestinal chyme among four treatments (P>0.05). The trypsin activity in the anterior segment of the small intestine was higher than other segments, whereas the α-amylase activity in the posterior segment of the small intestine was higher than other segments. Leucine can reduce Isc of the rumen and duodenum, improve the development of the gastrointestinal tract, and enhance trypsin activity; phenylalanine could inhibit the effect of leucine in promoting intestinal development.

Metal-carbenicillin framework-based nanoantibiotics with enhanced penetration and highly efficient inhibition of MRSA.

The development of effective therapies to control methicillin-resistant Staphylococcus aureus (MRSA) infections is challenging because antibiotics can be degraded by the production of certain enzymes, for example, ß-lactamases. Additionally, the antibiotics themselves fail to penetrate the full depth of biofilms formed from extracellular polymers. Nanoparticle-based carriers can deliver antibiotics with better biofilm penetration, thus combating bacterial resistance. In this study, we describe a general approach for the construction of ß-lactam antibiotics and ß-lactamase inhibitors co-delivery of nanoantibiotics based on metal-carbenicillin framework-coated mesoporous silica nanoparticles (MSN) to overcome MRSA. Carbenicillin, a ß-lactam antibiotic, was used as an organic ligand that coordinates with Fe3+ to form a metal-carbenicillin framework to block the pores of the MSN. Furthermore, these ß-lactamase inhibitor-loaded nanoantibiotics were stable under physiological conditions and could synchronously release antibiotic molecules and inhibitors at the bacterial infection site to achieve a better elimination of antibiotic resistant bacterial strains and biofilms. We confirmed that these ß-lactamase inhibitor-loaded nanoantibiotics had better penetration depth into biofilms and an obvious effect on the inhibition of MRSA both in vitro and in vivo.

Using graphene oxide high near-infrared absorbance for photothermal treatment of Alzheimer's disease.

A novel strategy to dissociate amyloid aggregation is presented, using localised heat generation from a clinically used amyloid staining dye, thioflavin-S (ThS)-modified graphene oxide (GO) under NIR laser irradiation. Compared to traditional chemotherapies, photothermal therapy shows reduced side effects and improved selectivity and safety.

[Experimental study on treatment of systemic lupus erythematosus with langchuang-3 granule].

OBJECTIVE: To investigate the mechanism of action of Chinese drug Langchuang-3 Granule (LC-3) in treating systemic lupus erythematosus (SLE) through observing its effects on body weight (BW), antinuclear antibody (ANA), spleen index and thymus index in BXSB SLE model mice, as well as the deposition of immune complex in mice' renal glomeruli. METHODS: SLE model mice were randomized into 4 groups: the control group (A), the LC-3 treated group (B), the Western drug treated group (C), and the LC-3 combined Western drug treated group (D). BW of mice was dynamically observed; spleen index (SI) and thymus index (TI) were measured by weighting method; serum anti-ANA level was detected by ELISA; IgG and complement C3 in renal glomeruli were analysed by direct immunofluorescence. RESULTS: BW of mice remarkably increased after treatment in Group B and D, showing a significant difference to that in Group A (P < 0.05). Lower TI level and higher SI level were found in the model mice. As compared with Group A, TI was higher in Group B and D, SI was lower in Group D, and both indices were lower in Group C (P < 0.05 or P < 0.01). Level of ANA decreased (converting from positive to negative) remarkably in all the three treated groups (P < 0.01). The fluorescence intensity of IgG and C3 in the renal tissue was weaker in Group B, C (both P < 0.05) and D (P < 0.01) than that in Group A. CONCLUSION: Both LC-3 and Western medicine showed remarkable effects in treating SLE model mice, and the combination of the two could display an effect better than that of using either alone.