Raman spectroscopy study on terephthalamide crystal at high pressures.

In this study, we have investigated the structural stability of terephthalamide (TPA) crystal at pressure from ambient to 15 GPa in the diamond anvil cell at room temperature by Raman spectroscopy. Assignment for the Raman vibration modes of TPA crystal at ambient conditions has been performed based on the density functional theory (DFT) calculations. Pressure-induced structural transition was monitored using in-situ Raman spectroscopy.

High pressure Raman study of isobutyramide.

Isobutyramide (IBA) has attracted considerable attention due to its expansive prospects for practical applications in the synthesis of drugs, dyes and other organic compounds. Herein we perform the high-pressure studies of IBA crystal by Raman spectral measurements at room temperature from ambient pressure to 30 GPa by using diamond anvil cells (DACs) to gain comprehensive insights into its structure and stability. Raman vibrational modes of IBA crystal at ambient pressure are resolved based on the experimental results and the first-principles theoretical calculations.

Temperature-dependent study of Fermi resonance of CHCN and CHCN---Li complex in CHCN-LiClO mixture by Raman spectroscopy.

The Raman spectra of acetonitrile-LiClO mixture solution have been measured in the temperature range 20 to -196 °C at ambient pressure. Detailed Raman spectroscopy analysis revealed that, in acetonitrile-LiClO mixture solution, the liquid CHCN transformed into solid phase β at approximately -50 °C, and then into solid phase α at approximately -60 °C. Besides, the Fermi resonance parameters of CHCN and CHCN---Li complex at different temperatures were calculated by using the Bertran's equations, respectively.

Study the effect of Li on the ν/ν+ν Fermi resonance of acetonitrile by Raman Spectroscopy.

Raman spectra of the solution of LiClO in acetonitrile (CHCN) at different concentrations have been measured. With increasing the concentration of Li, it was noted that several vibrational modes of CHCN had significant changes in Raman shifts and some new Raman peaks emerged due to the CHCN⋯Li complex formation. In addition, Fermi resonance phenomenon between the ν and (ν + ν) Raman bands of CHCN⋯Li complex was observed.

Regulatory NK cells mediated between immunosuppressive monocytes and dysfunctional T cells in chronic HBV infection.

Background And Aims: HBV infection represents a major health problem worldwide, but the immunological mechanisms by which HBV causes chronic persistent infection remain only partly understood. Recently, cell subsets with suppressive features have been recognised among monocytes and natural killer (NK) cells. Here we examine the effects of HBV on monocytes and NK cells.

Dysregulates Monocytes and Inhibits Macrophage Polarization through LC3-Dependent Autophagy.

Brucellosis is caused by infection with species and exhibits diverse clinical manifestations in infected humans. Monocytes and macrophages are not only the first line of defense against infection but also a main reservoir for . In the present study, we examined the effects of infection on human peripheral monocytes and monocyte-derived polarized macrophages.

Hepatitis C Virus Induces MDSCs-Like Monocytes through TLR2/PI3K/AKT/STAT3 Signaling.

Background And Aims: Recent studies reveal the accumulation of myeloid derived suppressor cells (MDSCs) in human peripheral blood mononuclear cells (PBMCs) following HCV infection, which may facilitate and maintain HCV persistent infection. The mechanisms by which HCV induces MDSCs are poorly understood. In the present study, we investigated the mechanisms by which HCV induces MDSCs that lead to suppression of T cell proliferation and expansion of CD4+Foxp3+ regulatory T cells.

HCV core protein inhibits polarization and activity of both M1 and M2 macrophages through the TLR2 signaling pathway.

Hepatitis C virus (HCV) establishes persistent infection in most infected patients, and eventually causes chronic hepatitis, cirrhosis, and hepatocellular carcinoma in some patients. Monocytes and macrophages provide the first line of defense against pathogens, but their roles in HCV infection remains unclear. We have reported that HCV core protein (HCVc) manipulates human blood-derived dendritic cell development.

IL-10 plays a central regulatory role in the cytokines induced by hepatitis C virus core protein and polyinosinic acid:polycytodylic acid.

Hepatitis C virus (HCV) can cause persistent infection and chronic liver disease, and viral factors are involved in HCV persistence. HCV core protein, a highly conserved viral protein, not only elicits an immunoresponse, but it also regulates it. In addition, HCV core protein interacts with toll-like receptors (TLRs) on monocytes, inducing them to produce cytokines.

The Role of Immune Cells in Chronic HBV Infection.

Hepatitis B virus (HBV) infection is a major cause of chronic liver diseases that may progress to liver cirrhosis and hepatocellular carcinoma. Host immune responses are important factors that determine whether HBV infection is cleared or persists. After infection, viral replication occurs inside hepatocytes, and the secretion of infectious virions can take place at high rates for decades.

Hepatitis C virus core protein triggers expansion and activation of CD4(+)CD25(+) regulatory T cells in chronic hepatitis C patients.

CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) are increased in patients with chronic hepatitis C, which may contribute to the sustained suppression of hepatitis C virus (HCV)-specific T-cell responses and viral persistence in HCV-infected individuals. We postulated that HCV core protein (HCVc) directly contributes to the expansion of Tregs in HCV-infected patients, and we provide evidence to support this hypothesis in the report. Peripheral blood mononuclear cells (PBMCs) and sera were collected from 87 treatment-naïve chronic HCV-infected patients, CD4(+)CD25(+) Tregs were measured by flow cytometry, and HCV RNA and HCVc levels were detected using qPCR and enzyme-linked immunosorbent assay (ELISA), respectively.

Role of helicity of α-helical antimicrobial peptides to improve specificity.

A major barrier to the use of antimicrobial peptides as antibiotics is the toxicity or ability to lyse eukaryotic cells. In this study, a 26-residue amphipathic α-helical antimicrobial peptide A12L/A20L (Ac-KWKSFLKTFKSLKKTVLHTLLKAISS-amide) was used as the framework to design a series of D- and L-diastereomeric peptides and study the relationships of helicity and biological activities of α-helical antimicrobial peptides. Peptide helicity was measured by circular dichroism spectroscopy and demonstrated to correlate with the hydrophobicity of peptides and the numbers of D-amino acid substitutions.