Nan Qi

A monolithically integrated optical receiver comprising a four-channel microring-based WDM array, Ge-Si photodetectors (PDs) and a co-designed high-speed electronic front end is presented. The receiver achieves 112 Gb/s PAM-4 operation per channel with a power consumption of 0.71 pJ/bit and a bandwidth density of 437.5 Gb/s/mm². The four-channel wavelength division multiplexing (WDM) array supports an aggregate data throughput of 448 Gb/s. These results demonstrate good optical filtering and detector performance, offering a practical path toward dense, high-speed monolithic integration for optical interconnects.

Influenza A virus (IAV) is the primary pathogen responsible for seasonal and pandemic influenza, causing 3 to 5 million severe cases and approximately 290,000 to 650,000 deaths annually worldwide [...

Host restriction factors and viral evasion strategies involved in the virus-host arms races remain to be discovered. Through an initial membrane protein-targeted CRISPR-Cas9 screening, we identified Acyl-CoA synthetase long-chain family member 3 (ACSL3) as a restriction factor against influenza A virus (IAV). Clinical transcriptomic analysis shows that ACSL3 is upregulated in peripheral blood mononuclear cells from mildly ill patients with influenza. Ectopic expression and loss-of-function validation demonstrate the physiological role of ACSL3 in restricting viral proliferation of diverse IAV subtypes (H1N1, H3N2, H3N8) in vitro and in vivo. Mechanistically, ACSL3 potentiates the antiviral unfolded protein response (UPR) by engaging the endoplasmic reticulum (ER) stress sensors IRE1α and PERK, thereby enhancing the IRE1α-XBP1-s driven inflammation and inhibiting the PERK-ATF4-CHOP mediated apoptosis. Conversely, IAV triggers the lysosomal degradation of ACSL3 and thus reprograms UPR to promote an immunologically silent apoptosis for viral egress and dissemination. Our findings establish ACSL3 as a molecular switch balancing the UPR-mediated antiviral response, and reveal a targeted viral evasion strategy in the virus-host interplay.

A comprehensive molecular epidemiological study was conducted on a vancomycin‐resistant Enterococcus faecium (VR‐Efm) outbreak in Guangdong, China, with the aim of analyzing transmission routes and antimicrobial resistance patterns, developing specific diagnostic tools for early detection, and elucidating genetic relationships with previously reported strains. Strain identification was performed using matrix‐assisted laser desorption/ionization mass spectrometry, whereas whole‐genome sequencing was performed for bacterial genomic characterization. Comprehensive bioinformatic analyses, including multilocus sequence typing, phylogenetic tree construction, principal component analysis, minimum spanning tree, and comparative genomic analyses, were performed. Our genomic investigation identified as predominant the sequence type 80 strain of VR‐Efm, which exhibited a high level of resistance to a range of antibiotics, particularly vancomycin, amoxicillin, and teicoplanin. Through genome sequencing, we established genetic proximity between the outbreak strain and those previously identified in India and Japan. Furthermore, functional genomic analyses have elucidated genetic variations within critical genes, such as rsmH , which may be associated with the acquisition of antibiotic resistance. The identification of unique molecular markers within the outbreak strain facilitated the development of specific PCR assays, thereby significantly enhancing our capacity for early and precise detection of VR‐Efm. Our in‐depth genomic analysis of the VR‐Efm outbreak in Guangdong, China, identified a predominant ST80 strain that exhibited multidrug resistance, especially to vancomycin. This finding underscores the need for enhanced global public health surveillance to address this emerging threat.

Viral myocarditis, often caused by Coxsackievirus B (CVB), is the leading cause of dilated cardiomyopathy and heart failure. Despite extensive research, the pathogenesis of CVB infection remains incompletely understood. Our previous study found that Anisomycin inhibits CVB replication by promoting the degradation of eukaryotic translation elongation factor 1 alpha 1 (eEF1A1). However, the precise mechanism through which eEF1A1 facilitates the replication of CVB remains to be fully elucidated. Here, we demonstrated that upregulated eEF1A1 is required for CVB3 replication. In vitro transcription and RNA pulldown assay demonstrated that eEF1A1 binds to the 5' cloverleaf region of CVB3 RNA. We observed that eEF1A1 interacts with double-stranded viral RNA, viral precursor protein 3 CD, and poly(A)-binding protein (PABP), which enhances its interaction with 3 CD. We show that CVB3 upregulates eEF1A1 expression by activating NF-κB. Chromosome-immunoprecipitation assay confirmed that NF-κB p65 binds to the EEF1A1 promoter. Luciferase reporter assays validated that NF-κB up-regulates EEF1A1 transcription. We further showed that eEF1A1 promotes CVB3 replication through interacting with viral RNA, 3 CD, and cellular protein PABP. This study highlights that eEF1A1, which is essential for cellular translation, is manipulated by CVB3 to promote viral replication. These findings suggest that targeting eEF1A1 could be a potential antiviral strategy against CVB infection.

In the original publication [...].

Cholesterol is a key carbon source for Mycobacterium tuberculosis (Mtb) survival and persistence within macrophages. However, little is known about the role of cholesterol metabolism by Mtb in host-Mtb interplay. Here, we report the immune suppression mediated by Mtb's cholesterol metabolites. Conducting the cholesterol metabolic profiling and loss-of-function experiments, we show that the cholesterol oxidation products catalyzed by a thiolase FadA5 from Mtb H37Ra, 4-androstenedione (AD), and its derivant 1,4-androstenedione (ADD) inhibit the expression of pro-inflammatory cytokines and thus promote bacterial survival in bone marrow-derived macrophages (BMDMs). Our time-resolved fluorescence resonance energy transfer (TR-FRET)-based screening further identifies the nuclear receptor LXR alpha as the target of ADD. Activation of LXR alpha via ADD impedes the nuclear factor-kappa B (NF-kappa B) and mitogen-activated protein kinases (MAPK) signaling and reduces cholesterol accumulation in lipid rafts upon TLR4 simulation, thereby compromising the inflammatory responses. Our findings provide the evidence that Mtb could suppress the host immunity through its cholesterol metabolic enzyme and products, which are potential targets for screening novel anti-tuberculosis (TB) agents.