Immunoglobulin class-switch recombination: Mechanism, regulation, and related diseases.

Maturation of the secondary antibody repertoire requires class-switch recombination (CSR), which switches IgM to other immunoglobulins (Igs), and somatic hypermutation, which promotes the production of high-affinity antibodies. Following immune response or infection within the body, activation of T cell-dependent and T cell-independent antigens triggers the activation of activation-induced cytidine deaminase, initiating the CSR process. CSR has the capacity to modify the functional properties of antibodies, thereby contributing to the adaptive immune response in the organism.

Triterpene esters of and their anti-inflammatory activity.

Two new triterpene fatty acid esters, 3-palmityloxy-12,27-cyclofriedoolean-14-en-11-ol () and 3-palmityloxy-19-hydroxyursane (), together with 3-hydroxy-11-oxo-olean-12-enyl palmitate () were isolated from the potent anti-inflammatory active fraction of the petroleum ether-soluble part of ethanol extract. Compound was found to be a rare 12,27-cyclopropane triterpenoid. Their structures were determined through spectral data analysis combined with literature reports.

Seco-nortriterpenoids from Cirsium setosum and their anti-inflammatory activity.

Five unusual seco-nortriterpenoids, 3β-hydroxy-20,21-seco-30-nortaraxastan-20,21-dioic acid (1), 3β-hydroxy-20,21-seco-30-nortaraxastan-20-oic-21-oate (2), 3β-hydroxy-20-oxo-21,22-seco-30-nortaraxastan-22-oic acid (3), 3β-hydroxy-19-oxo-20,21-seco-29,30-nortaraxastan-21-oic acid (4) and 3β-hydroxy-19-oxo-20,21-seco-19-norlupan-21-oic acid (5) were isolated and elucidated from the anti-inflammatory activity fraction of the ethanol extract of Cirsium setosum. The structures of these compounds were established through spectroscopic methods. Preliminary biological assays showed that compounds 1-5 had significant inhibitory effect on NO production on lipopolysaccharide-stimulated RAW 264.

A review on cell damage, viability, and functionality during 3D bioprinting.

Three-dimensional (3D) bioprinting fabricates 3D functional tissues/organs by accurately depositing the bioink composed of the biological materials and living cells. Even though 3D bioprinting techniques have experienced significant advancement over the past decades, it remains challenging for 3D bioprinting to artificially fabricate functional tissues/organs with high post-printing cell viability and functionality since cells endure various types of stress during the bioprinting process. Generally, cell viability which is affected by several factors including the stress and the environmental factors, such as pH and temperature, is mainly determined by the magnitude and duration of the stress imposed on the cells with poorer cell viability under a higher stress and a longer duration condition.

Single-mode lasing in an AlGaInAs/InP dual-port square microresonator.

Mode selection is crucial to achieving stable single-mode lasing in microlasers. Here, we demonstrate experimentally a dual-port square microresonator for single-mode lasing with a side-mode-suppression ratio (SMSR) exceeding 40 dB. By connecting waveguides at two opposite vertices, the quality factor for the antisymmetric mode (ASM) is much higher than that of the symmetric mode (SM), enabling single-mode lasing.

Multi-omics research in sarcopenia: Current progress and future prospects.

Sarcopenia is a systemic disease with progressive and generalized skeletal muscle dysfunction defined by age-related low muscle mass, high content of muscle slow fibers, and low muscle function. Muscle phenotypes and sarcopenia risk are heritable; however, the genetic architecture and molecular mechanisms underlying sarcopenia remain largely unclear. In recent years, significant progress has been made in determining susceptibility loci using genome-wide association studies.

Corrigendum: Blood Immune Cell Composition Associated With Obesity and Drug Repositioning Revealed by Epigenetic and Transcriptomic Conjoint Analysis.

[This corrects the article DOI: 10.3389/fphar.2021.

Blood Immune Cell Composition Associated with Obesity and Drug Repositioning Revealed by Epigenetic and Transcriptomic Conjoint Analysis.

This research was designed to analyze the composition of immune cells in obesity and identify novel and potent drugs for obesity management by epigenetic and transcriptomic conjoint analysis. DNA methylation data set (GSE166611) and mRNA expression microarray (GSE18897) were obtained from the Gene Expression Omnibus database. A total of 72 objects (35 obese samples and 37 controls) were included in the study.

[Evaluation of the quality of human settlement in downtown Fuzhou based on multi-source data].

The objective evaluation of human settlement in cities helps find the problems exposed in urban development and make targeted adjustments to improve urban environment. Taking the downtown of Fuzhou as the research area, the residential area as the research unit, using multi-source data such as meteorological monitoring data, remote sensing imagery, map points of interest data (POI), and land planning data, we constructed monitoring system of urban human settlement from four aspects: environmental health and comfort, traffic convenience, city safety, and life conve-nience. The TOPSIS method was used to conduct a comprehensive evaluation of human settlement.

Numerical simulation of all-optical logic gates based on hybrid-cavity semiconductor lasers.

All-optical switch and multiple logic gates have been demonstrated using a hybrid-cavity semiconductor laser composed of a square microcavity and a Fabry-Perot cavity experimentally. In this paper, two-section tri-mode rate equations with optical injection terms are proposed and applied to study all-optical logic gates of NOT, NOR, and NAND operations utilizing the hybrid-cavity laser. Steady-state and dynamical characteristics of all-optical multiple logic gates are simulated, taking into account the influence of mode frequency detuning, gain suppression coefficients, mode Q factor, injection energy, and biasing current.

Drug Repurposing for COVID-19 Treatment by Integrating Network Pharmacology and Transcriptomics.

Since coronavirus disease 2019 (COVID-19) is a serious new worldwide public health crisis with significant morbidity and mortality, effective therapeutic treatments are urgently needed. Drug repurposing is an efficient and cost-effective strategy with minimum risk for identifying novel potential treatment options by repositioning therapies that were previously approved for other clinical outcomes. Here, we used an integrated network-based pharmacologic and transcriptomic approach to screen drug candidates novel for COVID-19 treatment.

Interaction of Microglia and Astrocytes in the Neurovascular Unit.

The interaction between microglia and astrocytes significantly influences neuroinflammation. Microglia/astrocytes, part of the neurovascular unit (NVU), are activated by various brain insults. The local extracellular and intracellular signals determine their characteristics and switch of phenotypes.

Transactivation domain of Krüppel-like factor 15 negatively regulates angiotensin II-induced adventitial inflammation and fibrosis.

Krüppel-like factor (KLF) 15 has emerged as a critical regulator of fibrosis in cardiovascular diseases. However, the precise role that KLF15 and its functional domain played in adventitial inflammation and fibrosis remains unclear. This study aims to investigate the role of the transactivation domain (TAD) of KLF15 in angiotensin II (Ang II)-induced adventitial pathologic changes.