PD-1-Expressing SARS-CoV-2-Specific CD8+ T Cells Are Not Exhausted, but Functional in Patients with COVID-19.

Memory T cell responses have been demonstrated in COVID-19 convalescents, but ex vivo phenotypes of SARS-CoV-2-specific T cells have been unclear. We detected SARS-CoV-2-specific CD8+ T cells by MHC class I multimer staining and examined their phenotypes and functions in acute and convalescent COVID-19. Multimer+ cells exhibited early differentiated effector-memory phenotypes in the early convalescent phase. The frequency of stem-like memory cells was increased among multimer+ cells in the late convalescent phase. Cytokine secretion assays combined with MHC class I multimer staining revealed that the proportion of interferon-γ (IFN-γ)-producing cells was significantly lower among SARS-CoV-2-specific CD8+ T cells than those specific to influenza A virus. Importantly, the proportion of IFN-γ-producing cells was higher in PD-1+ cells than PD-1- cells among multimer+ cells, indicating that PD-1-expressing, SARS-CoV-2-specific CD8+ T cells are not exhausted, but functional. Our current findings provide information for understanding of SARS-CoV-2-specific CD8+ T cells elicited by infection or vaccination.

Photonically active bowtie nanoassemblies with chirality continuum.

Chirality is a geometrical property described by continuous mathematical functions1-5. However, in chemical disciplines, chirality is often treated as a binary left or right characteristic of molecules rather than a continuity of chiral shapes. Although they are theoretically possible, a family of stable chemical structures with similar shapes and progressively tuneable chirality is yet unknown. Here we show that nanostructured microparticles with an anisotropic bowtie shape display chirality continuum and can be made with widely tuneable twist angle, pitch, width, thickness and length. The self-limited assembly of the bowties enables high synthetic reproducibility, size monodispersity and computational predictability of their geometries for different assembly conditions6. The bowtie nanoassemblies show several strong circular dichroism peaks originating from absorptive and scattering phenomena. Unlike classical chiral molecules, these particles show a continuum of chirality measures2 that correlate exponentially with the spectral positions of the circular dichroism peaks. Bowtie particles with variable polarization rotation were used to print photonically active metasurfaces with spectrally tuneable positive or negative polarization signatures for light detection and ranging (LIDAR) devices.

Enantiomer-dependent immunological response to chiral nanoparticles.

Chirality is a unifying structural metric of biological and abiological forms of matter. Over the past decade, considerable clarity has been achieved in understanding the chemistry and physics of chiral inorganic nanoparticles1-4; however, little is known about their effects on complex biochemical networks5,6. Intermolecular interactions of biological molecules and inorganic nanoparticles show some commonalities7-9, but these structures differ in scale, in geometry and in the dynamics of chiral shapes, which can both impede and strengthen their mirror-asymmetric complexes. Here we show that achiral and left- and right-handed gold biomimetic nanoparticles show different in vitro and in vivo immune responses. We use irradiation with circularly polarized light (CPL) to synthesize nanoparticles with controllable nanometre-scale chirality and optical anisotropy factors (g-factors) of up to 0.4. We find that binding of nanoparticles to two proteins from the family of adhesion G-protein-coupled receptors (AGPCRs)-namely cluster-of-differentiation 97 (CD97) and epidermal-growth-factor-like-module receptor 1 (EMR1)-results in the opening of mechanosensitive potassium-efflux channels, the production of immune signalling complexes known as inflammasomes, and the maturation of mouse bone-marrow-derived dendritic cells. Both in vivo and in vitro immune responses depend monotonically on the g-factors of the nanoparticles, indicating that nanoscale chirality can be used to regulate the maturation of immune cells. Finally, left-handed nanoparticles show substantially higher (1,258-fold) efficiency compared with their right-handed counterparts as adjuvants for vaccination against the H9N2 influenza virus, opening a path to the use of nanoscale chirality in immunology.

Rare coding variants in 35 genes associate with circulating lipid levels-A multi-ancestry analysis of 170,000 exomes.

Large-scale gene sequencing studies for complex traits have the potential to identify causal genes with therapeutic implications. We performed gene-based association testing of blood lipid levels with rare (minor allele frequency < 1%) predicted damaging coding variation by using sequence data from >170,000 individuals from multiple ancestries: 97,493 European, 30,025 South Asian, 16,507 African, 16,440 Hispanic/Latino, 10,420 East Asian, and 1,182 Samoan. We identified 35 genes associated with circulating lipid levels; some of these genes have not been previously associated with lipid levels when using rare coding variation from population-based samples. We prioritize 32 genes in array-based genome-wide association study (GWAS) loci based on aggregations of rare coding variants; three (EVI5, SH2B3, and PLIN1) had no prior association of rare coding variants with lipid levels. Most of our associated genes showed evidence of association among multiple ancestries. Finally, we observed an enrichment of gene-based associations for low-density lipoprotein cholesterol drug target genes and for genes closest to GWAS index single-nucleotide polymorphisms (SNPs). Our results demonstrate that gene-based associations can be beneficial for drug target development and provide evidence that the gene closest to the array-based GWAS index SNP is often the functional gene for blood lipid levels.

Chronic hepatitis B baseline viral load and on-treatment liver cancer risk: A multinational cohort study of HBeAg-positive patients.

BACKGROUND AND AIMS: A single-nation study reported that pretreatment HBV viral load is associated with on-treatment risk of HCC in patients who are HBeAg-positive without cirrhosis and with chronic hepatitis B initiating antiviral treatment. We aimed to validate the association between baseline HBV viral load and on-treatment HCC risk in a larger, multinational cohort. APPROACH AND RESULTS: Using a multinational cohort from Korea, Hong Kong, and Taiwan involving 7545 adult patients with HBeAg-positive, without cirrhosis and with chronic hepatitis B who started entecavir or tenofovir treatment with baseline HBV viral load ≥5.00 log 10 IU/mL, HCC risk was estimated by baseline viral load. HBV viral load was analyzed as a categorical variable. During continuous antiviral treatment (median, 4.28 y), HCC developed in 200 patients (incidence rate, 0.61 per 100 person-years). Baseline HBV DNA level was independently associated with on-treatment HCC risk in a nonlinear pattern. HCC risk was lowest with the highest baseline viral load (≥8.00 log 10 IU/mL; incidence rate, 0.10 per 100 person-years), but increased sharply as baseline viral load decreased. The adjusted HCC risk was 8.05 times higher (95% CI, 3.34-19.35) with baseline viral load ≥6.00 and <7.00 log 10 IU/mL (incidence rate, 1.38 per 100 person-years) compared with high (≥8.00 log 10 IU/mL) baseline viral load ( p <0.001). CONCLUSIONS: In a multinational cohort of adult patients with HBeAg-positive without cirrhosis and with chronic hepatitis B, baseline HBV viral load was significantly associated with HCC risk despite antiviral treatment. Patients with the highest viral load who initiated treatment had the lowest long-term risk of HCC development.

Viral Load-Based Prediction of Hepatocellular Carcinoma Risk in Noncirrhotic Patients With Chronic Hepatitis B : A Multinational Study for the Development and External Validation of a New Prognostic Model.

BACKGROUND: A nonlinear association between serum hepatitis B virus (HBV) DNA levels and hepatocellular carcinoma (HCC) risk has been suggested in patients with chronic hepatitis B (CHB). OBJECTIVE: To develop and externally validate a prognostic model for HCC risk in noncirrhotic adult patients with CHB and no notable alanine aminotransferase (ALT) elevation. DESIGN: Multinational cohort study. SETTING: A community-based cohort in Taiwan (REVEAL-HBV [Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer-Hepatitis B Virus]; REACH-B [Risk Estimation for HCC in CHB] model cohort) and 8 hospital-based cohorts from Korea and Hong Kong (GAG-HCC [Guide with Age, Gender, HBV DNA-HCC] and CU-HCC [Chinese University-HCC] cohorts). PARTICIPANTS: Model development: 6949 patients with CHB from a Korean hospital-based cohort. External validation: 7429 patients with CHB combined from the Taiwanese cohort and 7 cohorts from Korea and Hong Kong. MEASUREMENTS: Incidence of HCC. RESULTS: Over median follow-up periods of 10.0 and 12.2 years, the derivation and validation cohorts identified 435 and 467 incident HCC cases, respectively. Baseline HBV DNA level was one of the strongest predictors of HCC development, demonstrating a nonlinear parabolic association in both cohorts, with moderate viral loads (around 6 log10 IU/mL) showing the highest HCC risk. Additional predictors included in the new model (Revised REACH-B) were age, sex, platelet count, ALT levels, and positive hepatitis B e antigen result. The model exhibited satisfactory discrimination and calibration, with c-statistics of 0.844 and 0.813 in the derivation and validation cohorts with multiple imputation, respectively. The model yielded a greater positive net benefit compared with other strategies in the 0% to 18% threshold. LIMITATION: Validation in cohorts of other races and receiving antiviral treatment was lacking. CONCLUSION: Our new prognostic model, based on the nonlinear association between HBV viral loads and HCC risk, provides a valuable tool for predicting and stratifying HCC risk in noncirrhotic patients with CHB who are not currently indicated for antiviral treatment. PRIMARY FUNDING SOURCE: Korean government.

Non-linear association of baseline viral load with on-treatment hepatocellular carcinoma risk in chronic hepatitis B.

OBJECTIVE: The association between baseline pretreatment serum HBV DNA levels and on-treatment hepatocellular carcinoma (HCC) risk remains controversial in patients with chronic hepatitis B (CHB). We aimed to investigate the association between baseline HBV viral load and on-treatment HCC risk in CHB patients without cirrhosis. DESIGN: Using a multicentre historical cohort study including 4693 hepatitis B e antigen (HBeAg)-negative and HBeAg-positive, adult CHB patients without cirrhosis who initiated antiviral treatment, HCC risk was estimated by baseline HBV viral load as a categorical variable. RESULTS: During a median of 7.6 years of antiviral treatment, 193 patients developed HCC (0.53 per 100 person- years). Baseline HBV DNA level was independently associated with on-treatment HCC risk in a non-linear, parabolic pattern. Patients with moderate baseline viral loads (5.00-7.99 log10 IU/mL) exhibited the highest HCC risk (HR, 2.60; p<0.001), followed by those with low viral loads (3.30-4.99 log10 IU/mL; HR, 1.66; p=0.11). Patients with high viral loads (≥8.00 log10 IU/mL) presented the lowest HCC risk. Particularly, patients with baseline HBV DNA levels 6.00-6.99 log10 IU/mL had the highest on-treatment HCC risk (HR, 3.36; p<0.001) compared with those with baseline HBV DNA levels≥8.00 log10 IU/mL. These findings were more prominent among HBeAg-positive patients, younger patients, or those with less advanced hepatic fibrosis. CONCLUSION: Patients with moderate baseline viral load, particularly around 6 log10 IU/mL, demonstrated the highest on-treatment HCC risk, despite long-term antiviral treatment. Early initiation of antiviral treatment, tailored to viral load, should be considered to minimise HCC risk in adult CHB patients without cirrhosis.

Tenofovir Is Associated With a Better Prognosis Than Entecavir for Hepatitis B Virus-Related Hepatocellular Carcinoma.

BACKGROUND AND AIMS: Whether tenofovir or entecavir has different effects on the prevention of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in secondary and tertiary preventive settings is still a matter of debate. This study aimed to compare the long-term prognosis of HCC between tenofovir and entecavir in patients with chronic hepatitis B. METHODS: Chronic hepatitis B patients diagnosed with HCC between November 2008 and December 2018 and treated with either entecavir or tenofovir at a tertiary center in Korea were included. The effect of tenofovir compared with entecavir on the prognosis of HBV-related HCC was assessed using multivariable-adjusted Cox and propensity score (PS)-matched analyses. Various predefined subgroup analyses were conducted. RESULTS: During a median follow-up period of 3.0 years, the mortality rate for entecavir-treated patients (n = 3469) was 41.2%, while tenofovir-treated patients (n = 3056) had a mortality rate of 34.6%. Overall survival (OS) was better in the tenofovir group (adjusted hazard ratio [aHR], 0.79; P < .001), which were consistently observed in the PS-matched analysis. The magnitude of the risk difference in OS was more prominent 2 years after the diagnosis of HCC (aHR, 0.50; P < .001) than 2 years before (aHR, 0.88; P = .005), and it was more pronounced in patients with earlier HCC stages. In all subgroups, except for those with shorter life expectancy, such as those with compromised liver function, tenofovir was associated with better OS compared with entecavir. CONCLUSIONS: Among patients with HBV-related HCC, those treated with tenofovir had a better prognosis than those treated with entecavir, particularly among those with prolonged survival.

Updated Reference Intervals for Alanine Aminotransferase in a Metabolically and Histologically Normal Population.

BACKGROUND & AIMS: This study aims to reevaluate upper reference limit (URL) for alanine aminotransferase (ALT) by considering the changing epidemiology of major liver diseases. We employed histological and metabolic parameters in Asian living liver donors. METHODS: We performed a retrospective analysis of 5455 potential living liver donors from 2005 to 2019. Participants were screened for hepatitis B, C, HIV, and alcohol use. Histologically and metabolically healthy participants were assessed using the Prati criteria (body mass index <23 kg/m2, triglyceride ≤200 mg/dL, fasting glucose ≤105 mg/dL, total cholesterol ≤220 mg/dL). The updated ALT-URL was determined as the 95th percentile among participants without hepatic steatosis and who met the Prati criteria. RESULTS: The median age was 30 years, with a male predominance (66.2%). Among 5455 participants, 3162 (58.0%) showed no hepatic steatosis, with 1553 (49.1%) meeting both the criteria for no steatosis and the Prati criteria for metabolic health. The updated URL for ALT in these participants was 34 U/L for males and 22 U/L for females, which was significantly lower than conventionally accepted values. Using this revised ALT-URL, 72.8% of males with ALT levels ≥34 U/L and 55.0% of females with ALT levels ≥22 U/L showed signs of steatosis, whereas 32.7% of males and 22.2% of females met the criteria for metabolic syndrome. CONCLUSIONS: Our study provided the newly established reference intervals for ALT levels in a metabolically and histologically verified Asian population. The proposed URL for ALT are 34 U/L and 22 U/L for males and females, respectively.

Neoplastic progression risk in females with Barrett's esophagus: a systematic review and meta-analysis of individual patient data.

BACKGROUND AND AIMS: Females with Barrett's esophagus (BE) have a lower risk of neoplastic progression than males, but sufficiently powered risk analyses are lacking. This systematic review and meta-analysis of individual patient data (IPD) aims to provide more robust evidence on neoplastic progression risk in females. METHODS: Systematic literature search of three electronic databases (Medline, Embase, Google Scholar) from inception until August 2023. Eligible studies (1) reported original data on progression from non-dysplastic BE (NDBE), indefinite for dysplasia (IND) or low-grade dysplasia (LGD) to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC), and (2) included female and male patients. IPD were quality controlled by two independent reviewers. Primary outcome was the association between sex and neoplastic progression risk, adjusted for risk factors using multivariable Cox regression analysis. Secondary outcomes were sex differences in time to progression and annual progression rate. RESULTS: IPD were obtained from 11/66 eligible studies, including 2.196 (31%) females. Neoplastic progression risk was lower in females (HR 1.44 for males vs females, 95%CI 1.13-1.82) after adjusting for age, smoking, medication use, hiatal hernia, BE length, and baseline pathology. Annual progression rate was 0.88% in females vs 1.29% in males. Time to progression was similar in both sexes; 3.7 years (IQR 2.1-7.7) in females, and 4.2 years (IQR 2.0-8.1) in males. CONCLUSION: Although females had a lower neoplastic progression risk, sex differences were smaller than previously reported and time to progression was similar for both sexes. Future research should focus on other factors than sex to identify low- and high-risk BE patients.

Baseline Viral Load and On-treatment Hepatocellular Carcinoma Risk in Chronic Hepatitis B: A Multinational Cohort Study.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) risk persists in patients with chronic hepatitis B (CHB) despite antiviral therapy. The relationship between pre-treatment baseline hepatitis B virus (HBV) viral load and HCC risk during antiviral treatment remains uncertain. METHODS: This multinational cohort study aimed to investigate the association between baseline HBV viral load and on-treatment HCC risk in 20,826 noncirrhotic, hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with baseline HBV DNA levels ≥2000 IU/mL (3.30 log10 IU/mL) who initiated entecavir or tenofovir treatment. The primary outcome was on-treatment HCC incidence, stratified by baseline HBV viral load as a categorical variable. RESULTS: In total, 663 patients developed HCC over a median follow-up of 4.1 years, with an incidence rate of 0.81 per 100 person-years (95% confidence interval [CI], 0.75-0.87). Baseline HBV viral load was significantly associated with HCC risk in a non-linear parabolic pattern, independent of other factors. Patients with baseline viral load between 6.00 and 7.00 log10 IU/mL had the highest on-treatment HCC risk (adjusted hazard ratio, 4.28; 95% CI, 2.15-8.52; P < .0001) compared with those with baseline viral load ≥8.00 log10 IU/mL, who exhibited the lowest HCC risk. CONCLUSION: Baseline viral load showed a significant, non-linear, parabolic association with HCC risk during antiviral treatment in noncirrhotic patients with CHB. Early initiation of antiviral treatment based on HBV viral load may help prevent irreversible HCC risk accumulation in patients with CHB.

Clinicopathologic and Molecular Characterization of Inflammatory Bowel Disease-Associated Neuroendocrine Carcinomas and Mixed Neuroendocrine-Non-Neuroendocrine Neoplasms.

The pathogenesis of neuroendocrine carcinomas (NECs) and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) in the gastrointestinal tract remains poorly understood. This study aims to characterize the clinicopathologic and molecular features of NEC/MiNEN in patients with inflammatory bowel disease (IBD). Eighteen surgically resected IBD-associated intestinal carcinomas with a minimum of 30% neuroendocrine component were collected from 6 academic centers and compared with a control group of 12 IBD-associated carcinomas lacking neuroendocrine differentiation. Both groups exhibited a male predominance and similar age distribution. The NEC/MiNEN group was more likely to have a higher percentage of Crohn disease (9/18 vs 1/12; P = .024), occur in the rectum (9/18 vs 3/12) and small intestine (4/18 vs 0/12) (P < .01), be diagnosed on resection without a preceding biopsy (6/18 vs 0/12; P = .057), and have unidentifiable precursor lesions (10/18 vs 1/12; P = .018) than the control group. Synchronous carcinoma, advanced tumor stage (pT3 and pT4), and lymph node metastasis occurred at similar rates; however, the NEC/MiNEN group had a higher incidence of angiovascular invasion (14/18 vs 4/12; P = .024), distant metastasis (8/18 vs 1/12; P = .049), mortality (8/18 vs 2/12; P = .058), and worse survival (Kaplan-Meier; P = .023) than the control group. All tested cases were mismatch repair proficient. A Ki-67 proliferation index ranged from 25% to 100%. Next-generation sequencing in 11 NEC/MiNEN cases revealed low tumor mutational burdens but complex genetic abnormalities commonly involving TP53 (9/11; 82%), FBXW7 (4/11; 36%), and APC (3/11; 27%) genes, with the other genetic alterations randomly occurring in 1 or 2 cases. The neuroendocrine component, which shared similar molecular alterations as the nonneuroendocrine component, was subcategorized into intermediate (G3a) and high grade (G3b); the higher grade correlated with more genetic alterations. In conclusion, IBD-associated NEC/MiNEN shows diverse histologic features, variable precursor lesions, intricate genetic abnormalities, and aggressive biologic behavior. The classification and grading of gastrointestinal NEC/MiNEN may be refined for better clinical management.

Clinicopathologic Features of Gastrointestinal Tract Langerhans Cell Histiocytosis.

Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin and CD1a, S100, and Langerin immunohistochemical-stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months. All pediatric patients had concurrent multisystem LCH, presented with GI symptoms, and showed nonpolypoid lesions. Seven (88%) showed multifocal GI disease, including 5 with multiple GI organ involvement. All sampled lesions from children exhibited infiltrative growth. More than half had died of the disease or manifested persistent LCH at last follow-up. Twenty-five of 39 (64%) adults had LCH involving only the GI tract (single system), with the remaining 14 (36%) exhibiting multisystem disease. Adult single-system GI LCH was typically encountered incidentally on screening/surveillance endoscopy (72%). Most exhibited isolated colorectal involvement (88%) as a solitary polyp (92%), with a well-demarcated/noninfiltrative growth pattern (70%), and excellent prognosis (100%). In comparison, adult patients with multisystem LCH more frequently presented with GI symptoms (92%, P < .001), noncolorectal GI site involvement (50%, P = .02), multifocal GI lesions (43%, P = .005), nonpolypoid lesions (71%, P < .001), infiltrative histologic growth pattern (78%, P = .04), and persistent disease (57%, P < .001). Adult patients with multisystem LCH appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrated that adults with single-system LCH involving the GI tract have an excellent prognosis, whereas multisystem LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, noncolorectal GI involvement, multifocal GI disease, nonpolypoid lesions, and infiltrative growth pattern.

Overexpressing Vitamin C Defective 2 reduces fertility and alters Ca2+ signals in Arabidopsis pollen.

A potential strategy to mitigate oxidative damage in plants is to increase the abundance of antioxidants, such as ascorbate (i.e. vitamin C). In Arabidopsis (A. thaliana), a rate-limiting step in ascorbate biosynthesis is a phosphorylase encoded by Vitamin C Defective 2 (VTC2). To specifically overexpress VTC2 (VTC2 OE) in pollen, the coding region was expressed using a promoter from a gene with ∼150-fold higher expression in pollen, leading to pollen grains with an eight-fold increased VTC2 mRNA. VTC2 OE resulted in a near-sterile phenotype with a 50-fold decrease in pollen transmission efficiency and a five-fold reduction in the number of seeds per silique. In vitro assays revealed pollen grains were more prone to bursting (greater than two-fold) or produced shorter, morphologically abnormal pollen tubes. The inclusion of a genetically encoded Ca2+ reporter, mCherry-GCaMP6fast (CGf), revealed pollen tubes with altered tip-focused Ca2+ dynamics and increased bursting frequency during periods of oscillatory and arrested growth. Despite these phenotypes, VTC2 OE pollen failed to show expected increases in ascorbate or reductions in reactive oxygen species, as measured using a redox-sensitive dye or a roGFP2. However, mRNA expression analyses revealed greater than two-fold reductions in mRNA encoding two enzymes critical to biosynthetic pathways related to cell walls or glyco-modifications of lipids and proteins: GDP-d-mannose pyrophosphorylase (GMP) and GDP-d-mannose 3',5' epimerase (GME). These results support a model in which the near-sterile defects resulting from VTC2 OE in pollen are associated with feedback mechanisms that can alter one or more signaling or metabolic pathways critical to pollen tube growth and fertility.

Chiral Spectroscopy of Nanostructures.

ConspectusChirality is ubiquitous in the universe and in living creatures over detectable length scales from the subatomic to the galactic, as exemplified in the two extremes by subatomic particles (neutrinos) and spiral galaxies. Between them are living creatures that display multiple levels of chirality emerging from hierarchically assembled asymmetric building blocks. Not too far from the bottom of this pyramid are the foundational building blocks with chiral atomic centers on sp3 carbon atoms exemplified by l-amino acids and d-sugars that are self-assembled into higher-order structures with increasing dimensions forming highly complex, amazingly functional, and energy-efficient living systems. The organization and materials employed in their construction inspired scientists to replicate complex living systems via the self-assembly of chiral components. Multiple studies pointed to unexpected and unique electromagnetic properties of chiral structures with nanoscale and microscale dimensions, including giant circular dichroism and collective circularly polarized scattering that their constituent units did not possess.To address the wide variety of chiral geometries observed in continuous materials, singular particles, and their complex systems, multiple analytic techniques are needed. Simultaneously, their spectroscopic properties create a pathway to multiple applications. For example, mirror-asymmetric vibrations at chiral centers formed by sp3 carbon atoms lead to optical activity for the infrared (IR) wavelength regions. At the same time, understanding the optical activity in, for example, the IR region enables biomedical applications because multiple modalities of biomedical imaging and vibrational optical activity (VOA) of biomolecules are known for IR range. In turn, VOA can be realized in both absorption and emission modalities due to large magnetic transition moments, as vibrational circular dichroism (VCD) or Raman optical activity (ROA) spectroscopy. In addition to the VOA, in the range of longer wavelengths, lattice vibrational mode or phononic behavior occurs in chiral crystals and nanoassemblies, which can be readily detected by terahertz circular dichroism (TCD) spectroscopy. Meanwhile, chiral self-assembly can induce circularly polarized light emission (CPLE) regardless of the existence of chirality in coassembled fluorophores. The CPLE from self-assembled chiral materials is particularly interesting because the CPLE can originate from both circularly polarized luminescence and circularly polarized scattering (CPS). Furthermore, because self-assembled nanostructures often exhibit stronger optical activity than their building blocks owing to dimension and resonance effects, the optical activity of single assembled nanostructures can be investigated by using microscopic technology combined with chiral optics. Here, we describe the state of the art for spectroscopic methods for the comprehensive analysis of chiral nanomaterials at various photon wavelengths, addressed with special attention given to new tools emerging both for materials with self-organized hierarchical chirality and single-particle spectroscopy.

Low-threshold 2†µm InAs/InP quantum dash lasers enabled by punctuated growth.

2 µm photonics and optoelectronics is promising for potential applications such as optical communications, LiDAR, and chemical sensing. While the research on 2 µm detectors is on the rise, the development of InP-based 2 µm gain materials with 0D nanostructures is rather stalled. Here, we demonstrate low-threshold, continuous wave lasing at 2 µm wavelength from InAs quantum dash/InP lasers enabled by punctuated growth of the quantum structure. We demonstrate low threshold current densities from the 7.1 µm width ridge-waveguide lasers, with values of 657, 1183, and 1944 A/cm2 under short pulse wave (SPW), quasi-continuous wave (QCW), and continuous wave operation. The lasers also exhibited good thermal stability, with a characteristic temperature T0 of 43 K under SPW mode. The lasing spectra is centered at 1.97 µm, coinciding with the ground-state emission observed from photoluminescence studies. We believe that the InAs quantum dash/InP lasers emitting near 2 µm will be a key enabling technology for 2 µm communication and sensing.

Response to atezolizumab plus bevacizumab specific for lung and lymph node metastases affects survival of patients with HCC.

BACKGROUND & AIMS: Tumour microenvironment heterogeneity among different organs can influence immunotherapy responses. Here, we evaluated the impact of differential organ-specific responses on survival in patients with advanced-stage hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab (Atezo/Bev). METHODS: We retrospectively analysed 366 consecutive patients with advanced-stage HCC treated with Atezo/Bev as first-line systemic treatment. Therapeutic response was assessed using RECIST v1.1. Patients were divided into an intention-to-treat (ITT) group (patients treated with ≥1 dose of Atezo/Bev) and a per-protocol (PP) analysis group (patients with at least one measurable lesion irrespective of location treated with ≥3 doses of Atezo/Bev). Overall response and organ-specific response at initial and best response were evaluated in the PP group. Responders were defined as patients achieving complete remission or partial response. Initial progressors were defined as patients with progressive disease after three doses of Atezo/Bev. RESULTS: The ITT and PP groups comprised 324 and 236 patients, respectively. In the PP group, the organ-specific response rate of lung and lymph node (LN) metastases at both initial and best responses were higher than those of intrahepatic lesions and macrovascular tumour thrombosis. Lung and LN-specific response rates were 21.1% and 23.5%, respectively, at initial response, and 24.7% and 31.4%, respectively, at best response. Both initial pulmonary and lymphatic progressors (adjusted hazard ratios [95% confidence intervals], 6.37 [2.10-19.3], and 8.36 [2.16-32.4], respectively) were independently associated with survival regardless of intrahepatic response. CONCLUSIONS: The response of metastatic HCC to the Atezo/Bev regimen may be used to determine whether to continue treatment or switch to second-line treatment at an early phase of therapy.

Improving the hepatitis C virus care cascade with the in-hospital Reflex tEsting ALarm-C (REAL-C) model.

BACKGROUND: The World Health Organization (WHO) has set targets to eliminate viral hepatitis, including hepatitis C virus (HCV) infection, by 2030. We present the results of the in-hospital Reflex tEsting ALarm-C (REAL-C) model, which incorporates reflex HCV RNA testing and sending alerts to physicians. METHODS: We conducted a retrospective study analysing the data of 1730 patients who newly tested positive for anti-HCV between March 2020 and June 2023. Three distinct periods were defined: pre-REAL-C (n = 696), incomplete REAL-C (n = 515) and complete REAL-C model periods (n = 519). The primary outcome measure was the HCV RNA testing rate throughout the study period. Additionally, we assessed the referral rate to the gastroenterology department, linkage time for diagnosis and treatment and the treatment rate. RESULTS: The rate of HCV RNA testing increased significantly from 51.0% (pre-REAL-C) to 95.6% (complete REAL-C). This improvement was consistent across clinical departments, regardless of patients' comorbidities. Among patients with confirmed HCV infection, the gastroenterology referral rate increased from 57.1% to 81.1% after the REAL-C model. The treatment rate among treatment-eligible patients was 92.4% during the study period. The mean interval from anti-HCV positivity to HCV RNA testing decreased from 45.1 to 1.9 days. The mean interval from the detection of anti-HCV positivity to direct-acting antiviral treatment also decreased from 89.5 to 49.5 days with the REAL-C model. CONCLUSION: The REAL-C model, featuring reflex testing and physician alerts, effectively increased HCV RNA testing rates and streamlined care cascades. Our model facilitated progress towards achieving WHO's elimination goals for HCV infection.

Tuning the CO2 Reduction Selectivity of an Immobilized Molecular Ag Complex beyond CO.

The electrochemical reduction of carbon dioxide (CO2) to produce fuels and chemicals has garnered significant attention. However, achieving control over the selectivity of the resulting products remains a challenging task, particularly within molecular systems. In this study, we employed a molecular silver complex immobilized on graphitized mesoporous carbon (GMC) as a catalyst for converting CO2 into CO, achieving an impressive selectivity of over 90% at -1.05 V vs RHE. Notably, the newly formed silver nanoparticles emerged as the active sites responsible for this high CO selectivity rather than the molecular system. Intriguingly, the introduction of copper ions into the restructured Ag-nanoparticle-decorated carbon altered the product selectivity. At -1.1 V vs RHE in 0.1 M KCl, we achieved a high C2 selectivity of 75%. Furthermore, not only the Ag-Cu bimetallic nanoparticle but also the small-sized Ag-Cu nanocluster decorated over GMC was proposed as active sites during catalytic reactions. Our straightforward approach offers valuable insights for fine-tuning the product selectivity of immobilized molecular systems, extending beyond C1 products.

Revisiting the steatosis-associated fibrosis estimator score in young Asian subjects with steatotic liver disease and consideration for population variability.

BACKGROUND AND AIM: The steatosis-associated fibrosis estimator (SAFE) score has been developed to distinguish clinically significant fibrosis in patients with steatotic liver disease (SLD). However, validation of its performance in Asian subjects is limited. This study aimed to evaluate the performance of the SAFE score in Asian subjects with biopsy-proven SLD and in different subgroups according to age, sex, and body mass index. METHODS: We retrospectively analyzed 6383 living liver donors who underwent a liver biopsy between 2005 and 2023. Of these, 1551 subjects with biopsy-proven SLD were included. The performance of the SAFE score was evaluated using areas under the curve and compared with those of the nonalcoholic fatty liver disease fibrosis score (NFS) and fibrosis-4 index (FIB-4). RESULTS: The prevalence of clinically significant fibrosis in the cohort was 2.2%. The proportion of subjects with a "low-risk" SAFE score was the highest (91.0%), followed by those with "intermediate-risk" (7.8%) and "high-risk" (1.2%) scores. The prevalence of fibrosis in subjects with low-risk, intermediate-risk, and high-risk scores was 1.6%, 6.6%, and 21.1%, respectively. The SAFE outperformed FIB-4 and NFS (area under the curve: 0.70 vs 0.64 for both NFS and FIB-4). However, it showed low diagnostic accuracy and sensitivity (27%) at the low cutoff (SAFE < 0) in subjects aged 30-39 years (fibrosis: 1.2%), despite having a high negative predictive value (0.99). CONCLUSION: While the SAFE score demonstrates superior performance compared with other noninvasive tests in Asian subjects with SLD, its performance varies across age groups. In younger subjects, particularly, its performance may be more limited.