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We propose a simple optical model, which consists of two Kerr nonlinear parallel planar waveguides sandwiching a one-dimensional photonic crystal for demonstrating the phenomenon of spontaneous symmetry breaking in optics. We study the shape and stability of soliton pairs propagating in two planar waveguides and the spontaneous symmetry breaking of the power distribution of solitons in the two waveguides. The results of numerical simulation show that there is supercritical type of spontaneous symmetry breaking in this system. More optical power P and smaller refractive index of photonic crystals C 0 make soliton solutions more prone to spontaneous symmetry breaking bifurcation. Asymmetric soliton solutions and symmetric soliton solutions correspond to different dispersion relations. Under the given total power P, for the symmetric soliton solutions, the propagation constant k increases linearly with C 0 , and for asymmetric soliton solutions, the propagation constant k decreases nonlinearly with C 0 . The minimum point of k (C 0) is just the demarkation between the symmetric soliton solutions and the asymmetric soliton solutions. If C 0 is fixed, the minimum point of the Hamiltonian of the system, E (P) , is also the critical point of the two different kinds of soliton solutions. We also study stable and unstable distributions of two kinds of soliton solutions. [ABSTRACT FROM AUTHOR]

The colorimetric sensor has made great achievements in glucose sensing and diabetes prediction due to its simplicity, visualization, and lack of need for sophisticated instruments. The noninvasive sampling method has received more attention. Herein, a colorimetric agarose gel sensor was constructed by combining Cu-doped carbon nanowires (CuCNWs) with excellent peroxidase-like activity and glucose oxidase (GOx). CuCNWs can effectively catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) with a maximum catalytic rate of 12.5 × 10–8 M s–1, which is superior to most nanomaterials reported. The modification by PVP can significantly improve the stability of CuCNWs under physiological conditions without affecting their catalytic activity. By introducing GOx, the sensitive detections of hydrogen peroxide (H2O2) and glucose in a wide range with the limit of detection as low as 30 nM and 0.2 μM can be achieved. Notably, the colorimetric agarose gel sensor exhibits a higher sensitivity than commercial test strips in detecting glucose in solution. Furthermore, it was applied to the detection of urine glucose. Diabetic urine can be easily distinguished from normal urine by judging color changes with the naked eye. This work is of great significance in guiding the construction of colorimetric agarose gel sensors and expands the applications of nanozymes in the biosensing fields. [ABSTRACT FROM AUTHOR]

Nanomaterial-based cancer therapy has recently emerged as a new therapeutic modality with the advantages of minimal invasiveness and negligible normal tissue toxicity over traditional cancer treatments. However, the complex microenvironment and self-protective mechanisms of tumors have suppressed the therapeutic effect of emerging antitumor modalities, which seriously hindered the transformation of these modalities to clinical settings. Due to the excellent biocompatibility, unique physicochemical properties and easy surface modification, carbon dots, as promising nanomaterials in the biomedical field, can effectively improve the therapeutic effect of emerging antitumor modalities as multifunctional nanoplatforms. In this review, the mechanism and limitations of emerging therapeutic modalities are described. Further, the recent advances related to carbon dot-based nanoplatforms in overcoming the therapeutic barriers of various emerging therapies are systematically summarized. Finally, the prospects and potential obstacles for the clinical translation of carbon dot-based nanoplatforms in tumor therapy are also discussed. This review is expected to provide a reference for nanomaterial design and its development for the efficacy enhancement of emerging therapeutic modalities. [ABSTRACT FROM AUTHOR]

Inhibition of protein fibrillation process with nanomaterials is a promising strategy to combat neurodegenerative diseases. Copper-based nanomaterials have been seldom utilized in fibrillation inhibiting research due to Copper ions are generally considered as accelerators of fibrosis. Here, we proposed ultra-small Zn doped Cu 2 S (Zn:Cu 2 S) QDs as inhibitors of human insulin (HI) fibrosis. ThT, DLS, CD and TEM confirm that Zn:Cu 2 S QDs effectively inhibited insulin fibrosis in a dose-dependent manner with lag phase time extended (beyond 13-time by Zn:Cu 2 S QDs of 1 mg·mL -1 ), final fibril formation and the conversion from α-helix to β-sheet reduced. Additionally, thermodynamics analyzed results reveal that the HI fluorescence quenching process is static quenching dominated, and the Zn:Cu 2 S QDs inhibit HI fibrosis mainly through specific electrostatic interaction with oligomers. The positively charged amino acid residues of oligomers bind to the negatively charged Zn:Cu 2 S QDs, which prevents the self-assembly of the oligomers from growing into mature fibers to enhance the stability of the protein. Unlike free Copper ions, the as-prepared QDs show an excellent inhibition in HI fibrillation, breaking through the bottleneck of copper-based materials in inhibiting protein fibrosis and providing a potential strategy to inhibit protein fibrosis in-situ by biosynthesizing copper-based fibrosis inhibitors., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Theranostic agents that integrated chemodynamic therapy (CDT) and imaging functions have great potential application in personalized cancer therapy. However, most theranostic agents were fabricated by chemically coupling two or more independent functional units with diagnostic or therapeutic capabilities, and therefore have a large size. To date, one-step synthesis of unmodified ultrasmall quantum dots (QDs) integrating CDT and fluorescence imaging capabilities remains a challenge. Herein, we reported a simple one-step synthesis method of ultrasmall (2.46 nm) Zn-doped Cu 2 S (Zn:Cu 2 S) QDs with inherent properties of both high CDT activity and near-infrared fluorescence imaging capability. The fluorescence of Cu 2 S QDs was significantly enhanced approximately tenfold after Zn doping due to the compensation of defects. In vitro and in vivo experiments demonstrated that the Zn:Cu 2 S QDs could specifically and significantly inhibit the cancer cell growth (inhibition rate exceeded 65%) without damaging the normal cells. Furthermore, the CDT mechanism study suggested that a Fenton-like reaction occurred after the Zn:Cu 2 S QDs entered the tumor cells, inducing apoptosis via the mitochondrial signaling pathway, and activating the production of reactive oxygen species (ROS) and autophagy to selectively eliminate tumor cells to achieve CDT. This work proposed a simple one-step synthesis of unmodified ultrasmall QDs with fluorescence imaging and CDT, which provides a promising strategy for QDs to act as multi-functional theranostic agents.

Amyloid fibrillation of protein is associated with a great variety of pathologic conditions. The aggregation of protein is a complicated process with multisteps, whereas most of the inhibitors with elaborately designed structures can show an inhibition effect only on the nucleation stages of protein fibrillation. Herein, oxidized carbon dots (CDs) were achieved to study the relationship between the surface properties of CDs and their inhibition effect on human insulin (HI) fibrillation. More oxygen-containing function groups can be obtained after oxidation reaction of CDs, such as -OH and -COOH. The results show that 10-1 CDs (the mass ratios of CD/KMnO 4 is 10:1), with the highest carboxyl group content, possess the best inhibition ability. All the nucleation, growth, and final phases can be retarded by 10-1 CDs, which have been studied in detail by fluorescence spectra. However, CDs without oxidation can show only a weak inhibition effect on the nucleation stage. The 10-1 CDs is demonstrated to binding with HI monomers much stronger than that of CDs by isothermal titration calorimetry (ITC). Moreover, molecular dynamics simulations (MD) studies indicate that CDs with more carboxyl groups can show stronger affinities with native or unfolded HI monomers, which may be mainly derived from the active binding sites of histidine residues (His5 and His10) on B-chain through electrostatic interaction. Because the unfolding of B-chain in HI is prior to that of A-chain in our MD simulations, the later aggregation of HI can be inhibited effectively by the stronger binding forces between 10 and 1 CDs and the B-chain of HI.

This study was purposed to investigate the effect of multiple myeloma patients' sera on hepcidin mRNA expression of Hep-3b hepatoma cell line and effect of human interleukin-6 (IL-6) antibody or recombinant human erythropoietin (rhEPO) on hepcidin mRNA expression. The clinical information and serum of multiple myeloma patients were collected. Their sera of a final concentration of 10% were added into Hep-3b cell medium. The mRNA from Hep-3b cells was extracted, and hepcidin mRNA expression was detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). A final concentration of 10 ng/ml human IL-6 antibody and 2 U/ml rhEPO were added into the medium respectively. The results showed that the sera of untreated multiple myeloma patients elevated hepcidin mRNA expression of Hep-3b cells, compared with healthy controls and iron deficiency anemia patients. This effect was fully neutralized by human IL-6 antibody or rhEPO. The hemoglobin (Hb) level was stable during the follow up of regularly treated multiple myeloma patients and the effect of MM patient serum on Hep-3b cell hepcidin mRNA expression was reduced. It is concluded that the hepcidin mRNA expression of Hep-3b cell can be increased by untreated multiple myeloma patient serum. This promotive effect can be antagonised by IL-6, which suggests that IL-6 may be possible to elevate expression level of hepcidin in Hep-3b cells and results in anemia of chronic disease (ACD). The above mentioned promotive effects also can be suppressed by rhEPO, which indicates that the rhEPO may possess curative effect for ACD disease. During short-term follow-up of treated patients with multiple myeloma the Hb level is stable, the influence of patients serum on hepcidin mRNA of Hep-3b cells decreases, which shows the stabilization of disease and amelioration of ACD patient status.

Objective: To explore the therapeutic mechanisms of interferon-beta (IFN-beta) and intravenous immunoglobulin (IVIG) for experimental peripheral neuropathy induced by Campilobacter jejuni (Cj) lipopolysaccharide (LPS)., Method: Forty healthy Wistar rats weighing 205 - 230 g were divided into IFN-beta, IVIG, IFN-beta plus IVIG and control groups. After the immune neuropathy was induced in the rats by Cj LPS, IFN-beta (1.3 microg/kg) was given by subcutaneous injection to the rats every other day for 6 weeks; IVIG [400 mg/(kg x d)] was given to the rats for five days, every other week for two times and IFN-beta [1.3 microg/(kg x d)] and IVIG [400 mg/(kg x d)] were given to the rats on the same days. Meanwhile, the control group was given PBS. The sera were collected in the 2nd, 4th and 6th week after therapy, the titers of anti-GM(1) IgG, MMP-9 and TNF-alpha in sera of immunized rats were measured by ELISA; histological study of sciatic nerve was performed and IgG on sciatic nerve was detected by immunohistochemistry in the 6th week., Results: (1) There were no significant differences in titers of anti-GM(1) IgG, MMP-9 and TNF-alpha among the 3 therapeutic groups and control group after therapy for 2 weeks (P > 0.05). (2) The titers of anti- GM(1) IgG, MMP-9 or TNF-alpha in the control group were much higher than those of the IFN-beta group, the IVIG group or the IFN-beta and IVIG group after therapy for 4 weeks (P > 0.01) and there were no significant differences in titers of antibody among the 3 therapeutic groups (P > 0.05); the titers of MMP-9 or TNF-alpha in the IFN-beta and IVIG group were lower than those of the IFN-beta group or the IVIG group (P < 0.05). (3) The titers of anti-GM(1) IgG, MMP-9 or TNF-alpha in the control group were much higher than those of the IFN-beta group, the IVIG group or the IFN-beta with IVIG group after therapy for 6 weeks (P > 0.01); the IFN-beta with IVIG group had much lower levels of all indexes than the IFN-beta group or the IVIG group (P < 0.01)., Conclusion: IFN-beta and IVIG showed therapeutic effects on immune peripheral neuropathy through inhibiting the humoral and cellular immunity simultaneously in the peripheral neuropathy induced by CJ LPS, treatment with combined IFN-beta and IVIG was more effective.

Objective: To understand the correlation of lower serum folate, and red blood cell (RBC) folate level with birth defects including unexplained recurrent pregnancy loss, and to evaluate the role of RBC folate level as a suitable marker for folate supplement., Methods: Two hundred and ninety-nine non-pregnant women at child-bearing age with a birth defect history were selected as birth defect group. The levels of serum and RBC folate, and serum vitamin B(12) were determined. By comparing with the group of non-pregnant women at child-bearing age without any birth defect history (control group), we evaluated the correlation between lower serum folate, RBC folate level and main kinds of birth defects including unexplained recurrent pregnancy loss. And the levels of serum and RBC folate of birth defect group were also determined and compared before and after oral folate intake (5 mg/d) for one month., Results: The serum folate level of birth defect group was not different from the control group (17 - 26 vs 14 nmol/L, P > 0.05). The RBC folate level of birth defect group except the urinary defect was significantly lower compared with the control group (233 - 547 vs 689 nmol/L, P < 0.05). After the oral folate intake (5 mg/d), the serum folate level of unexplained recurrent pregnancy loss group and neural tube defects group were significantly increased than before [(22 +/- 9) vs (27 +/- 12) nmol/L, (19 +/- 10) vs (25 +/- 18) nmol/L; P < 0.05]. The RBC folate level of unexplained recurrent pregnancy loss group and congenital heart defect group were significantly increased than before [(374 +/- 275) vs (567 +/- 397) nmol/L, (322 +/- 205) vs (527 +/- 351) nmol/L, P < 0.05]., Conclusion: RBC folate level is more closely correlated than serum folate level with the incidence of main birth defect.

Sequencing batch reactor (SBR) was used to treat digested piggery wastewater, in order to investigate the impact of proportion of adding raw wastewater. In consecutive experiments, the reactor with adding 30% raw wastewater could get low ammonia nitrogen (NH3-N), usually less than 10 mg/L in the effluent, while the reactors with adding 10% or 20% raw wastewater, concentration of NH3-N increased by degrees until reached 300 mg/L or 80 mg/L respectively at end of experiment. These can be explained by the facts that the reactor with adding 30% raw wastewater could maintain stable pH (about 7.7), whereas pH in the reactors with adding 10% or 20% raw wastewater decreased gradually until to below 5.5. Performance monitoring of a cycle of SBR indicate that the peak value of nitrite nitrogen (NO2(-)-N) and valley value of ammonia nitrogen (NH3-N) occur in the fourth, third and second hour after aeration beginning for the reactors with adding 10%, 20% and 30% raw wastewater respectively, which imply that the more is the proportion of adding raw wastewater, the fast does the ammonia oxidized. These results can be attributed to the facts the higher proportion of adding raw wastewater brought better denitrification resulting in stable and high pH. The batch experiment shows that the rate of denitrification has positive correlation with ratio of BOD5 to TN in influent. The consecutive and batch experiment all prove the proportion of adding raw wastewater must reach more than 30% for normal operation of post-treatment of digested piggery wastewater.

Objective: To study the relationship between copper and organic components, total flavonoids of Astragalus (TFA), total saponins of Astragalus (TSA) and total polysaccharide of Astragalus (TPA)., Method: TFA, TSA and TPA were extracted from Astragalus roots using different organic solvents, and determined by colorimetry. The concentration of copper in extracts was determined by graphite furnace atomic absorption spectrometry (GFAAS)., Result: Copper was found in TFA, TPA and TSA, and its concentration in TFA and TPA was higher; the content of copper was correlated significantly to that of TFA and TPA (r1(2) = 0.754 8, F1 = 57.202, P < 0.01 and r2(2) = 0.499, F2 = 21.906, P < 0.01), while not to that of TSA ( r3(2) = 0.0026, F3 = 0.041, P > 0.1)., Conclusion: Correlation analysis could reveal the relationship of copper with organic components in Astragalus roots; contents and structure characteristics of organic components might be important factors influencing the distribution of copper in Astragalus roots.

Objective: To study whether hematologic malignancy patients with anemia have a lower erythropoietin (EPO) response., Methods: Serum EPO levels were detected by ELISA in patients with hematologic malignancies and with iron deficiency anemia (IDA). Eighty patients with hematologic malignancies, including 13 multiple myeloma (MM), 7 chronic lymphocytic leukemia (CLL) and 60 non-Hodgkin's lymphoma (NHL) were studied. Thirty of them had anemia(21 NHL,6 MM and 3 CLL). Twenty patients with IDA were studied as the control., Results: Hematologic malignancy patients with anemia had higher EPO levels [(97.8 +/- 183.9) IU/L] than those with normal Hb values [(27.8 +/- 85.4) IU/L; P <0.01]. In patients with IDA, serum EPO response was inversely correlated with Hb level (r= -0.5, P <0.05) , but no such inverse correlation was found in the hematologic malignancy patients with anemia (r = -0.14). After corrected for Hb level, the serum EPO levels were significantly lower in anemic patients with hematologic malignancies than in IDA patients (P = 0.032) , indicating a decreased EPO response in the former group., Conclusion: Anemia associated with hematologic malignancy might result from an inappropriately low EPO response. EPO treatment for these patients may be beneficial.