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An enhanced configuration for a linearized MOS operational transconductance amplifier (OTA) is proposed. The proposed fully differential OTA circuit is based on resistive source degeneration and an improved adaptive biasing technique. It is robust to process variation, which has not been fully shown in previously reported linearization techniques. Detailed harmonic distortion analysis demonstrating the robustness of the proposed OTA is introduced. The transconductance gain is tunable from 160 to 340/[micro]S with a third-order intermodulation (IM3) below--70 dB at 26 MHz. As an application, a 26-MHz second-order low-pass filter fabricated in TSMC 0.35-[micro]m CMOS technology with a power supply of 3.3 V is presented. The measured IM3 with an input voltage of 1.4 Vpp is below--65 dB for the entire filter pass-band, and the input referred noise density is 156 nV/[square root of (Hz)]. The cutoff frequency of the filter is tunable in the range of 13-26 MHz. Theoretical and experimental results are in good agreement. Index Terms--Linearized operational transconductance amplifier (OTA), continuous-time filters, OTA-C filter, MOS transconductors, harmonic distortion, Volterra series.

Alzheimer's disease (AD) and vascular dementia (VaD) typically do not exhibit distinct differences in clinical manifestations and auxiliary examination results, which leads to a high misdiagnosis rate. However, significant differences in treatment approaches and prognosis between these two diseases underscore the critical need for an accurate diagnosis of AD and VaD. In this study, serum samples from 33 patients with AD patients, 37 patients with VaD, and 130 healthy individuals were collected, employing near-infrared aquaphotomics technology in combination with deep learning for differential diagnoses. Through an analysis of water absorption patterns among different diseases via aquaphotomics, the efficacies of traditional machine learning methods (Support Vector Machine and Decision Trees) and deep learning approaches (Deep Forest) in modeling were compared. Ultimately, by leveraging feature extraction techniques in conjunction with deep learning, a differential diagnostic model for AD and VaD was successfully developed. The results revealed that aquaphotomics could identify a certain correlation between the number of hydrogen bonds in water molecules and the development of AD and VaD; the deep learning model was found to be superior to traditional machine learning models, achieving an accuracy of 98.67 %, sensitivity of 97.33 %, and specificity of 100.00 %. The bands identified using the Competitive Adaptive Reweighting Algorithm method, primarily located at approximately 1300-1500 nm, showed a significant correlation with water molecules containing four hydrogen bonds. These results highlighted the potential role of the water molecule hydrogen-bond network in disease development and were consistent with the aquaphotomics analysis results. Therefore, the differential diagnostic model developed by integrating near-infrared spectroscopy and deep learning was proven to be effective and feasible, providing accurate and rapid diagnostic methods for AD and VaD diagnoses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Homoharringtonine (HHT) exhibits an anti-inflammatory activity. The potential protective effects and mechanisms of HHT on dextran sulfate sodium- (DSS-) induced colitis were investigated. DSS-induced colitis mice were intraperitoneally injected with HHT. Body weight, colon length, disease activity index (DAI), and histopathological change were examined. The relative contents of interleukin- (IL-) 1 β , tumor necrosis factor- (TNF-) α , IL-6, and the chemokine (C-C motif) ligand 2 (CCL2) in the colon tissues and HHT-treated RAW264.7 cells were detected with the enzyme-linked immunosorbent assay. In the meantime, the levels of p-p65 and p-I κ B α were detected by Western blot. The proportion of macrophages (CD11b + F4/80 + ) in the colon tissues was detected by flow cytometry. HHT alleviated DSS-induced colitis with downregulated TNF- α , IL-1 β , IL-6, and CCL2 expression; reduced activation of nuclear factor-kappa B (NF- κ B) signaling; and diminished proportion of recruited macrophages in colon tissues. It was further testified that HHT inhibited lipopolysaccharide-induced macrophage activation with reduced activation of NF- κ B signaling. In addition, HHT inhibited the M1 polarization of both human and mouse macrophages, while HHT did not affect the differentiation of human CD4 T cells into Th17, Th1, or Treg cells and did not affect the proliferation and migration of human colon epithelial cells. In summary, HHT attenuates DSS-induced colitis by inhibiting macrophage-associated NF- κ B activation and M1 polarization, which could be an option for the treatment of ulcerative colitis., Competing Interests: All authors declared that they had no competing interests., (Copyright © 2022 Jiangrui Liu et al.)

Endothelial microparticles (EMPs) are small vesicles released from endothelial cells (ECs) and found circulating in the blood. EMPs are formed by a plasma membrane surrounding a small amount of cytosol and contain a subset of cellular proteins. As the number of EMPs in the blood increases with certain diseases, they may be an attractive biomarker for clinical diagnosis. Proteomic analysis of EMPs has been previously performed by mass spectrometry. However, the proteomic information of the ECs that secrete EMPs is lacking. This study introduces an in vitro model of activated ECs we created for proteomic analyses and reports the changes of the protein content in the ECs and EMPs using proteomic methods. Thus, this study provides valuable information for the analysis of the highly dynamic secretion process of EMPs. There is a direct correlation between the proteins that form EMPs and tumor necrosis factor-α (TNF-α)-activated ECs. The endothelial proteins transferred by EMPs may play important roles in the interaction between EMPs and the target cells, which may lead to endothelial dysfunction.