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In this work, we propose to employ strong optical feedback to narrow the spectral linewidth of quantum cascade lasers without using any phase control. Rate equation analysis demonstrates that optical feedback beyond a certain level always reduces the laser linewidth for any feedback phase. It is also found that the linewidth becomes less sensitive to the feedback phase for higher feedback strength. Simulations show that optical feedback with a feedback ratio of −10 dB can suppress the laser linewidth by about two orders of magnitude. This is in contrast to near-infrared laser diodes, which can be easily destabilized by strong feedback. [ABSTRACT FROM AUTHOR]

Narrow-linewidth mid-infrared laser sources are highly demanding for high-resolution gas spectroscopy applications. Interband cascade lasers (ICLs) are power-efficient laser sources emitting in the mid-infrared range. This work unveils the low phase noise characteristics of distributed feedback ICLs driven by a battery source. We show that the measured spectral linewidth of ICLs is as narrow as 284 kHz (at a 1 ms observation time), which is smaller than those of common quantum cascade lasers. On the other hand, raising the pump current reduces the intrinsic linewidth down to 12 kHz. The linewidth broadening factor is in the range of 2.0–3.0, leading to a Schawlow–Townes linewidth as narrow as 1.6 kHz. This work suggests the high potential of developing battery-driven, high-resolution gas spectroscopy instruments using ICLs. [ABSTRACT FROM AUTHOR]

This work reports the linewidth broadening factor (LBF) of a continuous-wave interband cascade laser operated both below and above threshold. Using the Hakki-Paoli method, the below-threshold LBFs around the gain peak are determined to be in the range of 1.1–1.4, where the thermal effect is carefully removed. Employing the self-mixing interferometry technique, the above-threshold LBFs are measured to be around 2.2, which do not increase with increasing pump current. [ABSTRACT FROM AUTHOR]

Introduction. To examine the protective effects of Liu Wei Di Huang Wan formula (LWDH) on liver and orbitofrontal cortex (OFC) injuries in monosodium glutamate (MSG) and partial hepatectomy (PH) rat model. Methods. Neonatal Wistar rats were given MSG or saline on postnatal days 2, 4, 6, 8, and 10. The rats were caged into five groups and treated accordingly at six weeks old as follows: Saline group, Saline+PH group, MSG group, MSG+PH group, and LWDH group (MSG+PH+LWDH). The PH was performed during week 8 by excision of the left and median hepatic lobes (occupying about 68% of whole liver).On day 8 after the PH, the rats were subjected to an inner OFT before being sacrificed. The liver and OFC were stained using H&E, ORO, or Nissl staining. The expression of neurotrophic factors (β-NGF, BDNF) was examined in the OFC lysates by ELISA. Serum levels of cytokines (IL-1β, VEGF) were examined using the Bio-Plex suspension array. Results. LWDH increased the total distance traveled by the animals (p<0.05), and LWDH improved the integrity of the Nissl bodies in the OFC (mean area of the Nissl bodies, p<0.01; mean diameter, p<0.05; mean density, p<0.05; and IOD, p<0.01). There were less white area in the liver (p>0.05) and decreased hepatic steatosis (p<0.01) in LWDH group. LWDH administration decreased the expression of serum levels of IL-1β (p>0.05), while it increased VEGF (p>0.05) expression. LWDH administration increased the expression of BDNF (p>0.05) and β-NGF (p>0.05) in the OFC, all as compared to the MSG+PH group. Conclusion. LWDH partly protected the animals from depressive-like behaviors in the MSG+PH-induced liver regeneration neonatal rat model. LWDH alleviated hepatic injury and steatosis and, furthermore, protected the Nissl body integrity and the growth of neurites. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the antioxidant effect of the surface layer proteins (SLPs) and their mechanism. We investigated four SLPs which were extracted from L. casei zhang, L. rhamnosus , L. gasseri and L. acidophilus NCFM respectively using LiCl. The protective effect of SLPs on H 2 O 2 -induced HT-29 cells oxidative injury was investigated. As results, SLPs (100 μg/mL) could significantly mitigate HT-29 cells cytotoxicity, improve the activities of total antioxidant capacity (T-AOC), catalase (CAT) and superoxide dismutase (SOD), decrease the contents of malondialdehyde (MDA) and lactate dehydrogenase (LDH), compared with H 2 O 2 -induced group ( P < 0.05). Furthermore, SLPs were also shown to attenuate the apoptosis rate (10.94–24.03%, P < 0.01), suppress the elevation of intracellular reactive oxygen species (ROS) and calcium levels, restore mitochondrial membrane potential (MMP) and block the activation of apoptosis-related proteins of caspase-3 and caspase-9 ( P < 0.05). Considering all the parameters analyzed, we concluded that Lactobacillus SLPs play an essential role in the antioxidant capacity of HT-29 cells induced by H 2 O 2 , and the mechanism could be attributed to SLPs’ ability to enhance the activity of the intracellular antioxidant enzyme system, reduce ROS accumulation and to inhibit apoptosis by regulating mitochondrial pathway. [ABSTRACT FROM AUTHOR]

Ethnopharmacological Relevance. “Diwu Yanggan” (DWYG) has been reported to regulate liver regeneration, modulate the immune response, ameliorate liver injury, kill virus, ameliorate liver fibrosis, and suppress hepatic cancer. However, its mechanisms are still unknown. Objectives. To investigate the effects of DWYG on oval cell proliferation in 2-AAF/PH rats and determine its mechanism. Methods. Wistar rats were randomly distributed into normal group, sham group, vehicle group, and DWYG group. Hepatic pathological changes were examined by H&E staining. The oval cell markers CD34, AFP, CK-19 and hematopoietic cell markers CD45, Thy1.1, and hepatocyte marker ALB were examined with immunohistochemistry. The percentage of CD34/CD45 double-positive cells in bone marrow was detected by flow cytometry. Cytokine levels were measured with the Bio-plex suspension array system. Results. DWYG significantly increased the survival rates of 2-AAF/PH rats and promoted liver regeneration. Furthermore, DWYG increased the ratio of CD34/CD45 double-positive cells on days 10 and 14. In addition, DWYG gradually restored IL-1, GRO/KC, and VEGF levels to those of the normal group. Conclusions. DWYG increases 2-AAF/PH rat survival rates, suppresses hepatic precarcinoma changes, and restores hepatic tissue structure and function. DWYG may act by modulating the hepatic microenvironment to support liver regeneration. [ABSTRACT FROM AUTHOR]

• A rapid and sensitive method for simultaneous determination of 5 phenolic acids and 17 flavonoids in Artemisiae Argyi Folium. • The method was applied for the QC of mugwort samples and found Qi'ai possesses superiority in constituent abundance. • Relevance analysis was design to accurately define the key active ingredients in mugwort. A rapid and reliable LC–MS/MS method was developed for the quantitation of major components in Folium Artemisiae Argyi (mugwort), a widely used traditional Chinese herbal medicine. A total of 5 phenolic acids and 17 flavonoids were separated and simultaneously determined by using a Shiseido C 18 column (150 × 3.0 mm, 3 μm) and gradient elution of acetonitrile-aqueous formic acid (100:0.1, v/v) at a 0.5 mL min−1 flow rate, via multiple reaction monitor (MRM) in polarity switching mode. The quantitative method was validated in terms of sensitivity, linearity, precision, accuracy and stability, which proved to be sensitive, accurate and reproducible. Then 65 samples collected from different areas were selected for component analysis by LC–MS/MS and assessment of antioxidant activity using DPPH, ABTS, FRAP, O 2 − and OH scavenging assays. Grey relational analysis and partial least square regression were used to evaluate the relevance between chemicals and bioactivities, and the results indicated chlorogenic acid, isochlorogenic acid B, A, C, eriodictyol, jaceosidin and eupatilin made the key contribution to antioxidant activity. The present study combines chemical analysis and bioassay to identify bioactive markers, which possesses potential value for the activity-oriented quality control of mugwort. [ABSTRACT FROM AUTHOR]

Although extensive studies have demonstrated the functional impairment of antigen-specific CD4+ and CD8+ T-cells during chronic hepatitis C virus (HCV) infection, the functional status of global CD4+ and CD8+ T-cells remains unclear. In this report, we recruited 42 long-term (~20 years) treatment-naïve chronic HCV (CHC) patients and 15 healthy donors (HDs) to investigate differences in global CD4+ and CD8+ T-cells function. We show that CD4+ and CD8+ T-cells from CHC patients underwent increased apoptosis after TCR stimulation. Furthermore, IFN-γ, IL-9 and IP-10 were elevated in CHC patients’ plasma and promoted activation-induced T-cells death. Global CD4+ and CD8+ T-cells also showed unique transcriptional profiles in the expression of apoptosis-related genes. We identified BCL2, PMAIP1, and CASP1 in CD4+ T-cells and IER3 and BCL2A1 in CD8+ T-cells from CHC patients as HCV-specific gene signatures. Importantly, the gene expression patterns of CD4+ and CD8+ T-cells from CHC patients differ from those in CD4+ and CD8+ T-cells from human immunodeficiency virus type 1 (HIV-1) or hepatitis B virus (HBV) infected individuals. Our results indicate that chronic HCV infection causes a systemic change in cytokine levels that primes T-cells for activation-induced apoptosis. Furthermore, HCV infection programs unique apoptosis-related gene expression profiles in CD4+ and CD8+ T-cells, leading to their enhanced activation-induced apoptosis. These results provide novel insights to the pathogenesis of chronic HCV infection. [ABSTRACT FROM AUTHOR]

1-17-2 is a rat anti-human DEC-205 monoclonal antibody that induces internalization and delivers antigen to dendritic cells (DCs). The potentially clinical application of this antibody is limited by its murine origin. Traditional humanization method such as complementarity determining regions (CDRs) graft often leads to a decreased or even lost affinity. Here we have developed a novel antibody humanization method based on computer modeling and bioinformatics analysis. First, we used homology modeling technology to build the precise model of Fab. A novel epitope scanning algorithm was designed to identify antigenic residues in the framework regions (FRs) that need to be mutated to human counterpart in the humanization process. Then virtual mutation and molecular dynamics (MD) simulation were used to assess the conformational impact imposed by all the mutations. By comparing the root-mean-square deviations (RMSDs) of CDRs, we found five key residues whose mutations would destroy the original conformation of CDRs. These residues need to be back-mutated to rescue the antibody binding affinity. Finally we constructed the antibodies in vitro and compared their binding affinity by flow cytometry and surface plasmon resonance (SPR) assay. The binding affinity of the refined humanized antibody was similar to that of the original rat antibody. Our results have established a novel method based on epitopes scanning and MD simulation for antibody humanization. [ABSTRACT FROM AUTHOR]

Tumor-associated antigens (TAAs) have been tested in various clinical trials in cancer treatment but the patterns of specific T cell response to personalized TAA immunization remains to be fully understood. We report antigen-specific T cell responses in patients immunized with dendritic cell vaccines pulsed with personalized TAA panels. Tumor samples from patients were first analyzed to identify overexpressed TAAs. Autologous DCs were then transfected with pre-manufactured mRNAs encoding the full-length TAAs, overexpressed in the patients' tumors. Patients with glioblastoma multiforme (GBM) or advanced lung cancer received DC vaccines transfected with personalized TAA panels, in combination with low-dose cyclophosphamide, poly I:C, imiquimod and anti-PD-1 antibody. Antigen-specific T cell responses were measured. Safety and efficacy were evaluated. A total of ten patients were treated with DC vaccines transfected with personalized TAA panels containing 3–13 different TAAs. Among the seven patients tested for anti-TAA T cell responses, most of the TAAs induced antigen-specific CD4+ and/or CD8+ T cell responses, regardless of their expression levels in the tumor tissues. No Grade III/IV adverse events were observed among these patients. Furthermore, the treated patients were associated with favorable overall survival when compared to patients who received standard treatment in the same institution. Personalized TAA immunization-induced-specific CD4+ and CD8+ T cell responses without obvious autoimmune adverse events and was associated with favorable overall survival. These results support further studies on DC immunization with personalized TAA panels for combined immunotherapeutic regimens in solid tumor patients. Trial registration ClinicalTrials.gov, NCT02709616 (March, 2016), NCT02808364 (June 2016), NCT02808416 (June, 2016). [ABSTRACT FROM AUTHOR]

Chronic hepatitis B virus (HBV) infection is a major global health burden. Functional exhaustion and numerical reduction of HBV-specific cytotoxic T lymphocytes (CTLs) in the liver and peripheral blood limit anti-HBV CTL activity in patients with chronic HBV infection (CHB). However, the ongoing anti-HBV CD8+ T cell responses in the lymphoid organs are largely unknown due to the infeasibility of obtaining lymphoid organs from CHB patients. Here we demonstrate that the percentage of HBV-specific CD8+ T cells is higher in the spleen of CHB patients than that from peripheral blood and liver. Although they do respond to TCR stimulation and produce IFNγ, the cells proliferate poorly. Furthermore, miR-720 expression is upregulated in HBV-specific CD8+ T cells. Overexpression of miR-720 in primary human CD8+ T cells inhibits TCR stimulation-induced proliferation. We also demonstrate that TGFβ sustains miR-720 upregulation after TCR stimulation, and blood TGFβ levels are associated with the outcome of type I interferon treatment of CHB patients. Thus, therapies targeting miR-720 may help restore impaired immunity in CHB patients. [ABSTRACT FROM AUTHOR]