Clinically Applicable AI System for Accurate Diagnosis, Quantitative Measurements, and Prognosis of COVID-19 Pneumonia Using Computed Tomography.

Many COVID-19 patients infected by SARS-CoV-2 virus develop pneumonia (called novel coronavirus pneumonia, NCP) and rapidly progress to respiratory failure. However, rapid diagnosis and identification of high-risk patients for early intervention are challenging. Using a large computed tomography (CT) database from 3,777 patients, we developed an AI system that can diagnose NCP and differentiate it from other common pneumonia and normal controls. The AI system can assist radiologists and physicians in performing a quick diagnosis especially when the health system is overloaded. Significantly, our AI system identified important clinical markers that correlated with the NCP lesion properties. Together with the clinical data, our AI system was able to provide accurate clinical prognosis that can aid clinicians to consider appropriate early clinical management and allocate resources appropriately. We have made this AI system available globally to assist the clinicians to combat COVID-19.

A novel galactose electrochemical biosensor intended for point-of-care measurement of quantitative liver function using galactose single-point test.

Liver disease has emerged as a healthcare burden because of high hospitalization rates attributed both to steatohepatitis and to severe hepatic toxicity associated with changes of drug exposure. Early detection of hepatic insufficiency is critical to preventing long-term liver damage. The galactose single-point test is recommended by the US FDA as a sensitive means to quantify liver function, yet the conventional method used for quantitation of circulating galactose still relies on the standard colorimetric method, requiring time-consuming and labor-intensive processes, and is confined to the medical laboratory, thus limiting prevalence. To facilitate time- and cost-effective disease management particularly during a pandemic, a pocket-sized rapid quantitative device consisting of a biosensor and electrochemical detection has been developed. An in vitro validation study demonstrated that the coefficient of variation was less than 15% and deviations were between -4 and 14% in the range of 100-1500 µg/mL. The device presented good linear fit (correlation coefficient, r = 0.9750) over the range of 150-1150 µg/mL. Moreover, the device was found to be free from interference of common endogenous and exogenous substances, and deviated hematocrit, enabling a direct measurement of galactose in the whole blood without sample pre-treatment steps. The clinical validation comprising 118 subjects showed high concordance (r = 0.953) between the device and the conventional colorimetric assay. Thus, this novel miniaturized device is reliable and robust for routine assessment of quantitative liver function intended for follow-up of hepatectomy, drug dose adjustment, and screening for galactosemia, allowing timely and cost-effective clinical management of patients.

A Double-blind, Randomized Phase 2 Controlled Trial of Intradermal Hepatitis B Vaccination With a Topical Toll-like Receptor 7 Agonist Imiquimod, in Patients on Dialysis.

BACKGROUND: Patients on dialysis are hyporesponsive to the hepatitis B virus vaccines (HBVv). We examined intradermal (ID) HBVv Sci-B-Vac, with topical Toll-like receptor 7 (TLR7) agonist imiquimod pretreatment in dialysis patients. METHODS: We enrolled and prospectively followed adult patients on dialysis between January 2016 and September 2018. Eligible patients were randomly allocated (1:1:1) into 1 treatment group, topical imiquimod cream followed by ID HBVv (IMQ + ID); and 2 control groups: topical aqueous cream (placebo) followed by ID HBVv (AQ + ID) or topical aqueous cream followed by intramuscular HBVv (AQ + IM). The primary endpoint was the seroprotection rate (hepatitis B surface antibody ≥10 mIU/mL) at 52 weeks. RESULTS: Ninety-four patients were enrolled, among which 57.4% were previous nonresponders. Seroprotection rate was significantly better at week 52 for the IMQ + ID group with 96.9% compared to 74.2% and 48.4% for AQ + ID and AQ + IM groups, respectively (P < .0001). The geometric mean concentration was significantly higher at week 52 for the IMQ + ID group: 1135 (95% confidence interval [CI], 579.4-2218.2) mIU/mL, compared to 86.9 (95% CI, 18.5-409.3) mIU/mL and 7.2 (2.0-26.5) mIU/mL for the AQ + ID and AQ + IM groups, respectively (P < .0001). IMQ + ID vaccination (odds ratio, 3.70 [95% CI, 1.16-11.81]; P = .027) was the only factor independently associated with higher 52-week seroprotection rate. Adverse reaction was infrequent. CONCLUSIONS: Pretreatment with topical imiquimod before ID HBVv Sci-B-Vac was safe with favorable seroprotection in dialysis patients. CLINICAL TRIALS REGISTRATION: NCT02621112.

Preclinical evaluation of the mono-PEGylated recombinant human interleukin-11 in cynomolgus monkeys.

The mono-PEGylated recombinant human interleukin-11 (rhIL-11) was evaluated for its pharmacology and toxicology profile in non-human primates. This PEGylated IL-11 (PEG-IL11) showed a much prolonged circulating half-life of 67h in cynomolgus monkeys as compared to its un-PEGylated counterpart (~3h) through subcutaneous administration, implicating that a single injection of the recommended dose will effectively enhance thrombopoiesis in humans for a much longer period of time compared to rhIL-11 in humans (t1/2=6.9h). The toxicokinetics study of single dose and multiple doses showed that systemic exposure was positively correlated with the dosing level, implying that efficacy and toxicity were mechanism-based. A single high dose at 6.25mg/kg through subcutaneous route revealed tolerable and transient toxicity. Multiple-dose in monkeys receiving 0.3mg/kg weekly of the drug developed only mild to moderate toxicity. Major adverse events and immunogenicity in monkeys were only observed in the overdose groups. Bones were positively impacted; while reversible toxicities in heart, liver, kidney and lung observed were likely to be consequences of fluid retention. In summary, the PEG moiety on rhIL-11 did not elicit additional toxicities, and the drug under investigation was found to be well tolerated in monkeys after receiving a single effective dose of 0.1-0.3mg/kg through subcutaneous delivery, which may be allometrically scaled to a future clinical dose at 30-100µg/kg, creating a potential long acting, safer, and more convenient treatment approach based on rhIL-11.

Efficient expression and isolation of recombinant human interleukin-11 (rhIL-11) in Pichia pastoris.

Current source of recombinant human interleukin-11 (rhIL-11) is isolated from a fusion protein expressed by E. coli that requires additional enterokinase to remove linked protein, resulting in product heterogeneity of N-terminal sequence. Due to lack of glycosylation, rhIL-11 is suitable to be expressed by yeast cells. However, the only available yeast-derived rhIL-11 presents an obstacle in low production yield, as well as an unamiable process, such as the use of reverse-phase chromatography employing plenty of toxic organic solvents. Our findings showed that the low yield was due to self-aggregation of rhIL-11. A novel process recovering bioactive rhIL-11 from the yeast secretory medium therefore has been developed and demonstrated, involving fermentation from Pichia pastoris, followed by a two-phase extraction to precipitate rhIL-11. After renaturing, the protein of interest was purified by a two-column step, comprising a cation-exchanger, and a hydrophobic interaction chromatography in tandem at high sample loads that was facile and cost-effective in future scale-up. Identity and quality assessments confirmed the expected amino acid sequence without N-terminal heterogeneity, as well as high quality in potency and purity. Such a process provides an alternative and adequate supply of the starting material for the PEGylated rhIL-11.

KX2-361: a novel orally bioavailable small molecule dual Src/tubulin inhibitor that provides long term survival in a murine model of glioblastoma.

PURPOSE: A major challenge to developing new therapies for patients with malignant brain tumors is that relatively few small molecule anticancer drugs penetrate the blood-brain barrier (BBB) well enough to provide therapeutically effective concentrations in brain tissue before drug exposure in non-CNS tissues results in unacceptable toxicity. METHODS: KX2-361, a member of a novel family of compounds with Src-kinase and tubulin polymerization inhibitory activity, demonstrates good oral bioavailability and readily crosses the BBB in mice. The objective of this study was to investigate the activity of KX2-361 against human and murine glioma cells and assess its therapeutic effect in a syngeneic orthotopic model of glioblastoma. RESULTS: In addition to reducing the level of Src autophosphorylation in the GL261 murine glioblastoma cell line, KX2-361 binds directly to tubulin and disrupts microtubule architecture in glioma cells maintained in culture. CONCLUSIONS: The drug is active in vivo against orthotopic GL261 gliomas in syngeneic C57BL/6 mice. Long term survival is not observed in mice lacking an adaptive immune system, indicating that KX2-361 works in concert with the host immune system to control tumor growth and promote long-term survival in the GL261 glioma model.

TRANSFORMing theory to practice: Developing and implementing an anti-racist, community-based racial stress and trauma group intervention for BIPOC youth.

Evidence-informed trauma interventions developed specifically by and for Black, Indigenous, and People of Color (BIPOC) that address racial, historical, and intergenerational trauma are sparse, particularly for youth. To meet this need, the current study developed and piloted a new intervention - Trauma and Racism Addressed by Navigating Systemic Forms of Oppression using Resistance Methods (TRANSFORM) - using a and community-engaged research-to-practice approach. Across two phases, we documented the community-participatory development of TRANSFORM and analyzed preliminarily quantitative data collected in a pilot study with N = 19 BIPOC youth. Phase 1 reports on the process and lessons learned from the community centered co-development. The phase 2 pilot study results revealed statistically significant pretest-to-posttest reductions in racial discrimination stress as well as trauma-related symptoms interfering with daily functioning for youth. Implications for community-based approaches to disrupting and healing racial stress and trauma within and across youth-serving systems are discussed.

Transformer-based AI technology improves early ovarian cancer diagnosis using cfDNA methylation markers.

Epithelial ovarian cancer (EOC) is the deadliest women's cancer and has a poor prognosis. Early detection is the key for improving survival (a 5-year survival rate in stage I/II is over 70% compared to that of 25% in stage III/IV) and can be achieved through methylation markers from circulating cell-free DNA (cfDNA) using a liquid biopsy. In this study, we first identify top 500 EOC markers differentiating EOC from healthy female controls from 3.3 million methylome-wide CpG sites and validated them in 1,800 independent cfDNA samples. We then utilize a pretrained AI transformer system called MethylBERT to develop an EOC diagnostic model which achieves 80% sensitivity and 95% specificity in early-stage EOC diagnosis. We next develop a simple digital droplet PCR (ddPCR) assay which archives good performance, facilitating early EOC detection.

SARS-CoV-2 Delta and Omicron variants resist spike cleavage by human airway trypsin-like protease.

Soluble host factors in the upper respiratory tract can serve as the first line of defense against SARS-CoV-2 infection. In this study, we described the identification and function of a human airway trypsin-like protease (HAT), capable of reducing the infectivity of ancestral SARS-CoV-2. Further, in mouse models, HAT analogue expression was upregulated by SARS-CoV-2 infection. The antiviral activity of HAT functioned through the cleavage of the SARS-CoV-2 spike glycoprotein at R682. This cleavage resulted in inhibition of the attachment of ancestral spike proteins to host cells, which inhibited the cell-cell membrane fusion process. Importantly, exogenous addition of HAT notably reduced the infectivity of ancestral SARS-CoV-2 in vivo. However, HAT was ineffective against the Delta variant and most circulating Omicron variants, including the BQ.1.1 and XBB.1.5 subvariants. We demonstrate that the P681R mutation in Delta and P681H mutation in the Omicron variants, adjacent to the R682 cleavage site, contributed to HAT resistance. Our study reports what we believe to be a novel soluble defense factor against SARS-CoV-2 and resistance of its actions in the Delta and Omicron variants.

Assessment of reliability and validity of a handheld surface spine scanner for measuring trunk rotation in adolescent idiopathic scoliosis.

PURPOSE: To assess the reliability and validity of a handheld scanner (SpineScan3D) for trunk rotation measurement in adolescent idiopathic scoliosis (AIS) subjects, as compared with Scoliometer. METHODS: This was a cross-sectional study with AIS subjects recruited. Biplanar spine radiographs were performed using an EOS imaging system with coronal Cobb angle (CCA) determined. The angle of trunk rotation (ATR) was measured using Scoliometer. SpineScan3D was employed to assess the axial rotation of subjects' back at forward bending, recorded as surface tilt angle (STA). Intra- and inter-examiner repeats were conducted to evaluate the reliability of SpineScan3D. RESULTS: 97 AIS patients were recruited. Intra- and inter-examiner reliability of STA measures were good to excellent in major thoracic and lumbar curves (p < 0.001). A strong correlation was found between STA and ATR measures in both curve types (p < 0.001) with a standard error of the ATR estimate of between 1 and 2 degrees from linear regression models (R squared: 0.8-0.9, p < 0.001). A similar correlation with CCA was found for STA and ATR measures (r: 0.5-0.6, p < 0.002), which also demonstrated a similar sensitivity (72%-74%) and specificity (62%-77%) for diagnosing moderate to severe curves. CONCLUSION: SpineScan3D is a handheld surface scanner with a potential of wide applications in subjects with AIS. The current study indicated that SpineScan3D is reliable and valid for measuring trunk rotation in AIS subjects, comparable to Scoliometer. Further studies are planned to investigate its measurements in coronal and sagittal planes and the potential of this device as a screening and monitoring tool. TRIAL REGISTRATION NUMBER (DATE OF REGISTRATION): HKUCTR-2288 (06 Dec 2017). LEVEL OF EVIDENCE: Level III.

Gut microbiota-derived tryptamine and phenethylamine impair insulin sensitivity in metabolic syndrome and irritable bowel syndrome.

The incidence of metabolic syndrome is significantly higher in patients with irritable bowel syndrome (IBS), but the mechanisms involved remain unclear. Gut microbiota is causatively linked with the development of both metabolic dysfunctions and gastrointestinal disorders, thus gut dysbiosis in IBS may contribute to the development of metabolic syndrome. Here, we show that human gut bacterium Ruminococcus gnavus-derived tryptamine and phenethylamine play a pathogenic role in gut dysbiosis-induced insulin resistance in type 2 diabetes (T2D) and IBS. We show levels of R. gnavus, tryptamine, and phenethylamine are positively associated with insulin resistance in T2D patients and IBS patients. Monoassociation of R. gnavus impairs insulin sensitivity and glucose control in germ-free mice. Mechanistically, treatment of R. gnavus-derived metabolites tryptamine and phenethylamine directly impair insulin signaling in major metabolic tissues of healthy mice and monkeys and this effect is mediated by the trace amine-associated receptor 1 (TAAR1)-extracellular signal-regulated kinase (ERK) signaling axis. Our findings suggest a causal role for tryptamine/phenethylamine-producers in the development of insulin resistance, provide molecular mechanisms for the increased prevalence of metabolic syndrome in IBS, and highlight the TAAR1 signaling axis as a potential therapeutic target for the management of metabolic syndrome induced by gut dysbiosis.

Deep-learning-enabled protein-protein interaction analysis for prediction of SARS-CoV-2 infectivity and variant evolution.

Host-pathogen interactions and pathogen evolution are underpinned by protein-protein interactions between viral and host proteins. An understanding of how viral variants affect protein-protein binding is important for predicting viral-host interactions, such as the emergence of new pathogenic SARS-CoV-2 variants. Here we propose an artificial intelligence-based framework called UniBind, in which proteins are represented as a graph at the residue and atom levels. UniBind integrates protein three-dimensional structure and binding affinity and is capable of multi-task learning for heterogeneous biological data integration. In systematic tests on benchmark datasets and further experimental validation, UniBind effectively and scalably predicted the effects of SARS-CoV-2 spike protein variants on their binding affinities to the human ACE2 receptor, as well as to SARS-CoV-2 neutralizing monoclonal antibodies. Furthermore, in a cross-species analysis, UniBind could be applied to predict host susceptibility to SARS-CoV-2 variants and to predict future viral variant evolutionary trends. This in silico approach has the potential to serve as an early warning system for problematic emerging SARS-CoV-2 variants, as well as to facilitate research on protein-protein interactions in general.

Phase 1 clinical trial to assess safety and efficacy of NY-ESO-1-specific TCR T cells in HLA-A∗02:01 patients with advanced soft tissue sarcoma.

New York esophageal squamous cell carcinoma-1 (NY-ESO-1)-specific T cell receptor (TCR) T cell therapy is effective in tumors with NY-ESO-1 expression, but a safe and effective TCR-T cell therapeutic protocol remains to be improved. Here, we report a phase 1 investigational new drug clinical trial with TCR affinity-enhanced specific T cell therapy (TAEST16001) for targeting NY-ESO-1. Enrolled patients receive TAEST16001 cell infusion after dose-reduced lymphodepletion with cyclophosphamide (15 mg/kg/day × 3 days) combined with fludarabine (20 mg/m2/day × 3 days), and the TCR-T cells are maintained with low doses of interleukin-2 injection post-adoptive transfer. Analysis of 12 patients treated with the regimen demonstrates no treatment-related serious adverse events. The overall response rate is 41.7%. The median progression-free survival is 7.2 months, and the median duration of response is 13.1 months. The protocol of TAEST16001 cells delivers a safe and highly effective treatment for patients with advanced soft tissue sarcoma (ClinicalTrials.gov: NCT04318964).

Automated System for Multiplexing Detection of COVID-19 and Other Respiratory Pathogens.

OBJECTIVE: Infectious diseases are global health challenge, impacted the communities worldwide particularly in the midst of COVID-19 pandemic. The need of rapid and accurate automated systems for detecting pathogens of concern has always been critical. Ideally, such systems shall detect a large panel of pathogens simultaneously regardless of well-equipped facilities and highly trained operators, thus realizing on-site diagnosis for frontline healthcare providers and in critical locations such as borders and airports. METHODS & RESULTS: Avalon Automated Multiplex System, AAMST, is developed to automate a series of biochemistry protocols to detect nucleic acid sequences from multiple pathogens in one test. Automated processes include isolation of nucleic acids from unprocessed samples, reverse transcription and two rounds of amplifications. All procedures are carried out in a microfluidic cartridge performed by a desktop analyzer. The system was validated with reference controls and showed good agreement with their laboratory counterparts. In total 63 clinical samples, 13 positives including those from COVID-19 patients and 50 negative cases were detected, consistent with clinical diagnosis using conventional laboratory methods. CONCLUSIONS: The proposed system has demonstrated promising utility. It would benefit the screening and diagnosis of COVID-19 and other infectious diseases in a simple, rapid and accurate fashion. Clinical and Translational Impact Statement- A rapid and multiplex diagnostic system proposed in this work can clinically help to control spread of COVID-19 and other infectious agents as it can provide timely diagnosis, isolation and treatment to patients. Using the system at remoted clinical sites can facilitate early clinical management and surveillance.

Ruminococcus gnavus plays a pathogenic role in diarrhea-predominant irritable bowel syndrome by increasing serotonin biosynthesis.

Diarrhea-predominant irritable bowel syndrome (IBS-D), a globally prevalent functional gastrointestinal (GI) disorder, is associated with elevated serotonin that increases gut motility. While anecdotal evidence suggests that the gut microbiota contributes to serotonin biosynthesis, mechanistic insights are limited. We determined that the bacterium Ruminococcus gnavus plays a pathogenic role in IBS-D. Monocolonization of germ-free mice with R. gnavus induced IBS-D-like symptoms, including increased GI transit and colonic secretion, by stimulating the production of peripheral serotonin. R. gnavus-mediated catabolism of dietary phenylalanine and tryptophan generated phenethylamine and tryptamine that directly stimulated serotonin biosynthesis in intestinal enterochromaffin cells via a mechanism involving activation of trace amine-associated receptor 1 (TAAR1). This R. gnavus-driven increase in serotonin levels elevated GI transit and colonic secretion but was abrogated upon TAAR1 inhibition. Collectively, our study provides molecular and pathogenetic insights into how gut microbial metabolites derived from dietary essential amino acids affect serotonin-dependent control of gut motility.

Discovery and Characterization of Potent Dual P-Glycoprotein and CYP3A4 Inhibitors: Design, Synthesis, Cryo-EM Analysis, and Biological Evaluations.

Targeted concurrent inhibition of intestinal drug efflux transporter P-glycoprotein (P-gp) and drug metabolizing enzyme cytochrome P450 3A4 (CYP3A4) is a promising approach to improve oral bioavailability of their common substrates such as docetaxel, while avoiding side effects arising from their pan inhibitions. Herein, we report the discovery and characterization of potent small molecule inhibitors of P-gp and CYP3A4 with encequidar (minimally absorbed P-gp inhibitor) as a starting point for optimization. To aid in the design of these dual inhibitors, we solved the high-resolution cryo-EM structure of encequidar bound to human P-gp. The structure guided us to prudently decorate the encequidar scaffold with CYP3A4 pharmacophores, leading to the identification of several analogues with dual potency against P-gp and CYP3A4. In vivo, dual P-gp and CYP3A4 inhibitor 3a improved the oral absorption of docetaxel by 3-fold as compared to vehicle, while 3a itself remained poorly absorbed.

Jinhua Qinggan granules for non-hospitalized COVID-19 patients: A double-blind, placebo-controlled, and randomized controlled trial.

Background: Key findings from the World Health Organization Expert Meeting on Evaluation of Traditional Chinese Medicine (TCM) in treating coronavirus disease 2019 (COVID-19) reported that TCMs are beneficial, particularly for mild-to-moderate cases. The efficacy of Jinhua Qinggan granules (JHQG) in COVID-19 patients with mild symptoms has yet to be clearly defined. Methods: We conducted a phase 2/3, double-blind, randomized, placebo-controlled trial to evaluate the efficacy and safety of treatment with JHQG in mild, non-hospitalized, laboratory-confirmed COVID-19 patients. Participants were randomly assigned to receive 5 g/sacket of JHQG or placebo granules orally thrice daily for 10 days. The primary outcomes were the improvement in clinical symptoms and a proportion tested negative on viral polymerase chain reaction (PCR) after treatment. Secondary outcomes were the time to recover from clinical symptoms and changes in white blood cells (WBC) and acute phase reactants (C-reactive protein (CRP) and ferritin) on the 10th day after treatment initiation. Results: A total of 300 patients were randomly assigned to receive JHQG (150 patients) and placebo (150 patients). Baseline characteristics were similar in the two groups. In the modified intention-to-treat analysis, JHQG showed greater clinical efficacy (82.67%) on the 10th day of the trial compared with the placebo group (10.74%; rate difference: 71.93%; 95% CI 64.09-79.76). The proportion of patients with a negative PCR after treatment was comparable (rate difference: -4.67%; 95% CI -15.76 to 6.42). In contrast, all changes in WBC, ferritin, and CRP levels showed a statistically significant decline in JHQG (P ≤ 0.044) after treatment, but not the latter in placebo (P = 0.077). The median time to recovery of COVID-19-related symptoms including cough, sputum, sore throat, dyspnea, headache, nasal obstruction, fatigue, and myalgia was shorter in the JHQG group compared to the placebo group (P < 0.001 for all). Three patients experienced mild-to-moderate adverse events (AEs) duringthe treatment period in the JHQG group. Findings were similar between the modified intention-to-treat and the per-protocol analysis that included only patients who reported 100% adherence to the assigned regimen. Conclusion: Based on the time to recover from the COVID-19-related symptoms and AEs, it is concluded that JHQG is a safe and effective TCM for symptomatic relief of patients with mild COVID-19. A symptomatic improvement in the JHQG group patients was observed and JHQG use would have important public health implications in such patients. Clinical Trial Registration: The Trial was prospectively registered on www.clinicaltrials.gov with registration number: NCT04723524.

Hepatic expression of cell proliferation markers and growth factors in giant cell hepatitis: implications for the pathogenetic mechanisms involved.

OBJECTIVES: The aim of this study is to determine whether amitotic division or nuclear proliferation is involved in the formation of giant cells (GCs) in giant cell hepatitis (GCH). PATIENTS AND METHODS: Liver sections from 18 pediatric patients with idiopathic infantile GCH and 12 patients with postinfantile GCH were evaluated for the expression of proliferating cell nuclear antigen (PCNA) and human histone 3 (H3) mRNA, transforming growth factor-alpha (TGF-α), TGF-ß1, hepatocyte growth factor (HGF), and epidermal growth factor receptor (EGFR). RESULTS: Proliferation markers were detected in 1% to 80% in the nuclei of GC and non-GC hepatocytes in 10 of 18 (56%) infantile GCH biopsies and 11 of 12 (92%) postinfantile GCH biopsies, but not in normal liver. The expression of proliferation markers in GCs paralleled that in non-GC hepatocytes (P < 0.05 for both markers). TGF-α and EGFR were detected in both GCs (9/29 and 4/30 patients with infantile or postinfantile GCH, respectively) and non-GC hepatocytes (15/29 and 11/30 patients with infantile or postinfantile GCH, respectively). TGF-ß1 and HGF were detected mainly in sinusoidal cells in 20 of 29 and 10 of 30 patients with infantile or postinfantile GCH, respectively; the expression of HGF was positively correlated with PCNA and H3 mRNA in non-GC hepatocytes and with H3 mRNA in GCs (P < 0.01). CONCLUSIONS: Hepatic expressions of nuclear proliferation markers and growth factors were similar in infantile and postinfantile GCH, nuclear proliferation markers were detected in both GCs and non-GC hepatocytes in a high proportion of patients, and expression of HGF correlated positively with the proliferation markers. These data indicate that nuclear proliferation may contribute to the pathogenesis of GCs in at least a proportion of patients with GCH. A model for the pathogenesis of GCH is proposed.

COVID-19 Delta variants-Current status and implications as of August 2021.

The SARS-CoV-2 Delta variant has evolved as the dominant strain of the current pandemic. Studies have shown that this variant has increased infectivity/viral load, and reduced neutralization by the host antibodies from convalescent patients/vaccinees. Clinically, Delta variant infection has been observed/documented in convalescent patients/vaccinees, although with less incidence of severe diseases, but can serve as reservoir to spread the infection to the unvaccinated. The current understanding (as of 18 August 2021) on the virologic aspect (including the amino acid substitutions), clinical implications, and public health implications will be discussed in this mini review, and recommendations to health authorities will be provided.