Identification of Leishmania donovani PEX5-PTS1 Interaction Inhibitors through Fluorescence Polarization-Based High-Throughput Screening

Leishmaniasis, an infectious disease caused by pathogenic Leishmania parasites, affects millions of people in developing countries, and its re-emergence in developed countries, particularly in Europe, poses a growing public health concern. The limitations of current treatments and the absence of effective vaccines necessitate the development of novel therapeutics. In this study, we focused on identifying small molecule inhibitors which prevents the interaction between peroxin 5 (PEX5) and peroxisomal targeting signal 1 (PTS1), pivotal for kinetoplastid parasite survival. The Leishmania donovani PEX5, containing a C-terminal tetratricopeptide repeat (TPR) domain, was expressed and purified, followed by the quantification of kinetic parameters of PEX5-PTS1 interactions. A fluorescence polarization-based high-throughput screening assay was developed and small molecules inhibiting the LdPEX5-PTS1 interaction were discovered through the screening of a library of 51,406 compounds. Based on the confirmatory assay, nine compounds showed half maximal inhibitory concentration (IC50) values ranging from 3.89 to 24.50 µM. In silico docking using a homology model of LdPEX5 elucidated that the molecular interactions between LdPEX5 and the inhibitors share amino acids critical for PTS1 binding. Notably, compound P20 showed potent activity against the growth of L. donovani promastigotes, L. major promastigotes, and Trypanosoma brucei blood stream form, with IC50 values of 12.16, 19.21, and 3.06 μM, respectively. The findings underscore the potential of targeting LdPEX5-PTS1 interactions with small molecule inhibitors as a promising strategy for the discovery of new anti-parasitic compounds.

AI is a viable alternative to high throughput screening: a 318-target study

High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery.

High-throughput screening of small-molecules libraries identified antibacterials against clinically relevant multidrug-resistant A. baumannii and K. pneumoniae

BACKGROUND

The current pipeline for new antibiotics fails to fully address the significant threat posed by drug-resistant Gram-negative bacteria that have been identified by the World Health Organization (WHO) as a global health priority. New antibacterials acting through novel mechanisms of action are urgently needed. We aimed to identify new chemical entities (NCEs) with activity against Klebsiella pneumoniae and Acinetobacter baumannii that could be developed into a new treatment for drug-resistant infections.

METHODS

We developed a high-throughput phenotypic screen and selection cascade for generation of hit compounds active against multidrug-resistant (MDR) strains of K. pneumoniae and A. baumannii. We screened compound libraries selected from the proprietary collections of three pharmaceutical companies that had exited antibacterial drug discovery but continued to accumulate new compounds to their collection. Compounds from two out of three libraries were selected using "eNTRy rules" criteria associated with increased likelihood of intracellular accumulation in Escherichia coli.

FINDINGS

We identified 72 compounds with confirmed activity against K. pneumoniae and/or drug-resistant A. baumannii. Two new chemical series with activity against XDR A. baumannii were identified meeting our criteria of potency (EC50 ≤50 μM) and absence of cytotoxicity (HepG2 CC50 ≥100 μM and red blood cell lysis HC50 ≥100 μM). The activity of close analogues of the two chemical series was also determined against A. baumannii clinical isolates.

INTERPRETATION

This work provides proof of principle for the screening strategy developed to identify NCEs with antibacterial activity against multidrug-resistant critical priority pathogens such as K. pneumoniae and A. baumannii. The screening and hit selection cascade established here provide an excellent foundation for further screening of new compound libraries to identify high quality starting points for new antibacterial lead generation projects.

FUNDING

BMBF and GARDP.

Inhibition of DNMT3B expression in activated hepatic stellate cells overcomes chemoresistance in the tumor microenvironment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a complex disease associated with a plethora of environmental and genetic/hereditary causative risk factors, more so than other oncological indications. Additionally, patients with HCC exhibit fibrosis, cirrhosis, and liver-related disease. This complicated etiology can affect the disease course and likely contributes to its poor prognosis. In this study, we aimed to improve HCC therapy by evaluating combination treatment using anti-cancer and anti-fibrosis drugs via identification of novel anti-fibrosis drugs. We performed high-throughput screening of 10,000 compounds to identify hepatic fibrosis inhibitors through morphometry analysis of multicellular hepatic spheroid (MCHS) models and identified CHIR-99021 as a candidate anti-fibrotic drug. Treatment with CHIR-99021 induced loss of cell-cell interactions and suppression of extracellular matrix-related protein expression via reprogramming of hepatic stellate cell (HSC) activation in MCHSs. In particular, CHIR-99021 regulated DNMT3B expression only in activated HSCs. Moreover, CHIR-99021 markedly improved the efficacy of sorafenib in HCC- multicellular tumor spheroids in vitro and through induction of apoptosis by decreasing DNMT3B expression in vivo. In summary, these findings suggest that targeting HSC reprogramming by attenuation of DNMT3B expression in the tumor environment might represent a promising therapeutic strategy for liver fibrosis and HCC.

Madurastatins with Imidazolidinone Rings: Natural Products or Side-Reaction Products from Extraction Solvents?

Madurastatins are a group of pentapeptides containing an oxazoline moiety, and, in a few cases, an imidazolidinone ring as an additional structural feature. In our search for new potential antiparasitic metabolites from natural sources, we studied the acetone extracts from a culture of Actinomadura sp. CA-135719. The LC/HRMS analysis of this extract identified the presence of the known madurastatins C1 (1), D1 (4), and D2 (5) together with additional members of the family that were identified as the new madurastatins H2 (2) and 33-epi-D1 (3) after isolation and spectroscopic analysis. The planar structures of the new compounds were established by HRMS, ESI-qTOF-MS/MS, and 1D and 2D NMR data, and their absolute configuration was proposed using Marfey's and bioinformatic analyses of the biosynthetic gene cluster (BGC). A revision of the absolute configuration of madurastatins D1 and D2 is proposed. Additionally, madurastatins containing imidazolidinone rings are proved to be artifacts originating during acetone extraction of the bacterial cultures.

A pattern-centered analysis of adolescents' concerns and hopes about future crises: Differences in ways of coping and personal adjustment

INTRODUCTION

Many adolescents are concerned about global and future crises, such as the health of the planet or terrorism/safety. Yet, adolescents can also express hope about the future. Thus, asking adolescents about their concern and hope could yield subgroups with different ways of coping and personal adjustment.

METHOD

Australian adolescents (N = 863; age 10-16) completed surveys to report their concern (worry and anger) and hope about the planet, safety, jobs, income, housing, and technology, as well as their active and avoidant coping, depression, and life satisfaction.

RESULTS

Four distinct subgroups were identified using cluster analysis: Hopeful (low on concern and high on hope across all issues, 32%), Uninvolved (low in concern and hope; 26%), Concerned about the Planet (CP, 27%), and Concerned about Future Life (CFL, 15%). When compared (adjusting for age, sex, and COVID timing), the CP subgroup was highest in active coping (e.g., taking action) but moderate in personal adjustment. Hopeful had the most positive adjustment, whereas CFL had the poorest adjustment. Uninvolved were lowest in coping but moderate in adjustment.

CONCLUSIONS

Findings suggest ways of coping and adjustment may not always align, in that CP is connected with more active coping but also some cost to personal adjustment, whereas Hopeful is associated with optimal adjustment but perhaps at the cost of active coping. In addition, although CFL adolescents emerged as the at-risk group, the low levels of hope and coping in Uninvolved adolescents raise the possibility that they are at risk of future problems.

Garbage in, garbage out: how reliable training data improved a virtual screening approach against SARS-CoV-2 MPro

Introduction: The identification of chemical compounds that interfere with SARS-CoV-2 replication continues to be a priority in several academic and pharmaceutical laboratories. Computational tools and approaches have the power to integrate, process and analyze multiple data in a short time. However, these initiatives may yield unrealistic results if the applied models are not inferred from reliable data and the resulting predictions are not confirmed by experimental evidence. Methods: We undertook a drug discovery campaign against the essential major protease (MPro) from SARS-CoV-2, which relied on an in silico search strategy -performed in a large and diverse chemolibrary- complemented by experimental validation. The computational method comprises a recently reported ligand-based approach developed upon refinement/learning cycles, and structure-based approximations. Search models were applied to both retrospective (in silico) and prospective (experimentally confirmed) screening. Results: The first generation of ligand-based models were fed by data, which to a great extent, had not been published in peer-reviewed articles. The first screening campaign performed with 188 compounds (46 in silico hits and 100 analogues, and 40 unrelated compounds: flavonols and pyrazoles) yielded three hits against MPro (IC₅₀ ≤ 25 μM): two analogues of in silico hits (one glycoside and one benzo-thiazol) and one flavonol. A second generation of ligand-based models was developed based on this negative information and newly published peer-reviewed data for MPro inhibitors. This led to 43 new hit candidates belonging to different chemical families. From 45 compounds (28 in silico hits and 17 related analogues) tested in the second screening campaign, eight inhibited MPro with IC₅₀ = 0.12-20 μM and five of them also impaired the proliferation of SARS-CoV-2 in Vero cells (EC₅₀ 7-45 μM). Discussion: Our study provides an example of a virtuous loop between computational and experimental approaches applied to target-focused drug discovery against a major and global pathogen, reaffirming the well-known "garbage in, garbage out" machine learning principle.

A Genome-Wide RNAi Screen Reveals Common Host-Virus Gene Signatures: Implication for Dengue Antiviral Drug Discovery

Dengue is the most common mosquito-borne viral disease that in recent years has become a major international public health concern. Dengue is a tropical neglected disease with increasing global incidences, affecting millions of people worldwide, and without the availability of specific treatments to combat it. The identification of host-target genes essential for the virus life cycle, for which effective modulators may already exist, would provide an alternative path to a rapid drug development of the much needed antidengue agents. For this purpose, we performed the first genome-wide RNAi screen, combining two high-content readouts for dengue virus infection (DENV E infection intensity) and host cell toxicity (host cell stained nuclei), against an arrayed lentiviral-based short hairpin RNA library covering 16,000 genes with a redundancy of at least 5 hairpins per gene. The screen identified 1924 gene candidates in total; of which, 1730 gene candidates abrogated dengue infection, whereas 194 gene candidates were found to enhance its infectivity in HEK293 cells. A first pass clustering analysis of hits revealed a well-orchestrated gene-network dependency on host cell homeostasis and physiology triggering distinct cellular pathways for infectivity, replication, trafficking, and egress; a second analysis revealed a comprehensive gene signature of 331 genes common to hits identified in 28 published RNAi host-viral interaction screens. Taken together, our findings provide novel antiviral molecular targets with the potential for drug discovery and development.

Collaborative Virtual Screening Identifies a 2-Aryl-4-aminoquinazoline Series with Efficacy in an In Vivo Model of Trypanosoma cruzi Infection

Probing multiple proprietary pharmaceutical libraries in parallel via virtual screening allowed rapid expansion of the structure-activity relationship (SAR) around hit compounds with moderate efficacy against Trypanosoma cruzi, the causative agent of Chagas Disease. A potency-improving scaffold hop, followed by elaboration of the SAR via design guided by the output of the phenotypic virtual screening efforts, identified two promising hit compounds 54 and 85, which were profiled further in pharmacokinetic studies and in an in vivo model of T. cruzi infection. Compound 85 demonstrated clear reduction of parasitemia in the in vivo setting, confirming the interest in this series of 2-(pyridin-2-yl)quinazolines as potential anti-trypanosome treatments.

Strategies to build more effective interventions for elder abuse: a focus group study of nursing and social work professionals in Hong Kong

BACKGROUND

One in six older adults living in communities experience abuse and neglect. Elder abuse has serious consequences for individuals, families, and society, including mortality, physical and psychological morbidities, and increased care requirements. Timely and effective interventions for elder abuse should therefore be a priority. This study used a qualitative focus group approach to address the following questions: What are the essential elements of elder abuse interventions? What can be done to improve current interventions?

METHOD

The 32 participants in this focus group study included social workers, medical social workers, and nurses from seven organizations who shared their knowledge and insights. All sessions were conducted online, audio-recorded, and transcribed verbatim. Three researchers with backgrounds in social work and psychology independently coded the transcripts and agreed on the themes emerging from the focus groups.

RESULTS

Based on the experiences of frontline helping professionals in Hong Kong, we highlighted the key factors for effective elder abuse intervention: 1) identification and assessment; 2) essential skills and attitudes; 3) elements of effective interventions; 4) collaborative efforts across disciplines and agencies; and 5) raising awareness among professionals and the public.

CONCLUSIONS

Training can equip frontline professionals with the necessary skills to identify elder abuse cases and to assess the risk of abuse. Effective interventions should not only address clients' safety and need for tangible support but also respect their autonomy and privacy. A client-centered, strength-based approach that involves supportive peers and addresses the complex family relationships involved can be useful. Interventions should also involve cross-discipline and cross-agency collaboration.

Immunogenicity and Durability of Antibody Responses to Homologous and Heterologous Vaccinations with BNT162b2 and ChAdOx1 Vaccines for COVID-19

During the COVID-19 pandemic, vaccines were developed based on various platform technologies and were approved for emergency use. However, the comparative analysis of immunogenicity and durability of vaccine-induced antibody responses depending on vaccine platforms or vaccination regimens has not been thoroughly examined for mRNA- or viral vector-based vaccines. In this study, we assessed spike-binding IgG levels and neutralizing capacity in 66 vaccinated individuals prime-boost immunized either by homologous (BNT162b2-BNT162b2 or ChAdOx1-ChAdOx1) or heterologous (ChAdOx1-BNT162b2) vaccination for six months after the first vaccination. Despite the discrepancy in intervals for the prime-boost vaccination regimen of different COVID-19 vaccines, we found stronger induction and relatively rapid waning of antibody responses by homologous vaccination of the mRNA vaccine, while weaker boost effect and stable maintenance of humoral immune responses were observed in the viral vector vaccine group over 6 months. Heterologous vaccination with ChAdOx1 and BNT162b2 resulted in an effective boost effect with the highest remaining antibody responses at six months post-primary vaccination.

Need for a Standardized Translational Drug Development Platform: Lessons Learned from the Repurposing of Drugs for COVID-19

In the absence of drugs to treat or prevent COVID-19, drug repurposing can be a valuable strategy. Despite a substantial number of clinical trials, drug repurposing did not deliver on its promise. While success was observed with some repurposed drugs (e.g., remdesivir, dexamethasone, tocilizumab, baricitinib), others failed to show clinical efficacy. One reason is the lack of clear translational processes based on adequate preclinical profiling before clinical evaluation. Combined with limitations of existing in vitro and in vivo models, there is a need for a systematic approach to urgent antiviral drug development in the context of a global pandemic. We implemented a methodology to test repurposed and experimental drugs to generate robust preclinical evidence for further clinical development. This translational drug development platform comprises in vitro, ex vivo, and in vivo models of SARS-CoV-2, along with pharmacokinetic modeling and simulation approaches to evaluate exposure levels in plasma and target organs. Here, we provide examples of identified repurposed antiviral drugs tested within our multidisciplinary collaboration to highlight lessons learned in urgent antiviral drug development during the COVID-19 pandemic. Our data confirm the importance of assessing in vitro and in vivo potency in multiple assays to boost the translatability of pre-clinical data. The value of pharmacokinetic modeling and simulations for compound prioritization is also discussed. We advocate the need for a standardized translational drug development platform for mild-to-moderate COVID-19 to generate preclinical evidence in support of clinical trials. We propose clear prerequisites for progression of drug candidates for repurposing into clinical trials. Further research is needed to gain a deeper understanding of the scope and limitations of the presented translational drug development platform.

Efficacy of Prospective Memory Rehabilitation Plus Metacognitive Skills Training for Adults With Traumatic Brain Injury: A Randomized Controlled Trial

BACKGROUND

Prospective memory (PM) failure can limit independence and productivity following traumatic brain injury (TBI). Compensatory strategy use may ameliorate the effect of PM impairment on daily life but requires sufficient self-awareness. Metacognitive skills training (MST) can facilitate self-awareness and strategy use and may improve the efficacy of PM rehabilitation.

OBJECTIVE

To evaluate the effectiveness of compensatory strategy training (COMP) with an MST component (COMP-MST) for reducing everyday PM failure and improving psychosocial integration in adults with moderate-severe TBI, compared to COMP alone and a control condition. Secondary aims were to evaluate the effect of training on psychometric PM test scores, strategy use, self-awareness, and level of care.

METHODS

Assessor and participant-blinded randomized controlled trial with 52 participants (77% male, mean age = 39.0. SD = 13.6) allocated to 3 groups: COMP-MST, COMP, and waitlist control. Interventions were delivered over 6 weekly sessions. Measures were collected pre- and post-intervention and 3-month follow-up. Data were analyzed using unstructured linear mixed-effects modeling for repeated measures and planned contrasts between time-points for each group.

RESULTS

The models showed no significant differences between the groups on primary or secondary outcome measures. Significant pre-post intervention improvements were found for significant other's ratings of everyday PM failure for both intervention groups but not the control group, with medium to large effect sizes. Clinically relevant improvements on primary outcomes were found for participants across all 3 groups.

CONCLUSIONS

This study found no significant benefits of combining MST with COMP for improving everyday PM and psychosocial integration.

CLINICAL TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry https://www.anzctr.org.au/ ACTRN12615000996561.

Effectiveness of sensory modulation for people with schizophrenia: A multisite quantitative prospective cohort study

INTRODUCTION

Current research evidence suggests that people with schizophrenia have sensory processing difficulties. Sensory modulation has growing evidence for use in this population. This study aimed to evaluate the extent to which health, social, cognitive, and occupational functioning outcomes were impacted by sensory modulation interventions for people with schizophrenia.

METHODS

A prospective observational cohort study using a waitlist control design was used in two large hospital and health services in Queensland, Australia. The study recruited patients who used sensory modulation (n = 30) across the two hospitals and those who did not use sensory modulation interventions as a control (n = 11). Results were analysed using a series of planned comparisons including independent and paired t-tests, and mixed ANOVA was used whenever statistically indicated. The analysed measures were pre- and post-intervention scores.

RESULTS

This study found no statically significant differences between the control and intervention groups at both pre- and post-intervention. However, analysis of results from within the intervention group showed statistically significant improvements between pre- and post-test scores on distress, occupational functioning, and health and social functioning but not on sensory processing and global cognitive processing. Further analysis of results from this study, compared with those from an earlier study on the general population showed significant differences in Low Registration and Sensation Avoiding, as measured by the Adult/Adolescent Sensory Profile, between participants with schizophrenia and those without schizophrenia.

CONCLUSION

This study provides evidence to suggest that sensory modulation interventions can be complementary to standard care when utilised appropriately in clinical settings. Findings also suggest that the sensory profile of people with schizophrenia is different to that of the general population and this may have clinical implications. Further longitudinal research is needed with larger and randomised samples, using more targeted measures to better explore effectiveness of sensory modulation interventions.

A combination screening to identify enhancers of para-aminosalicylic acid against Mycobacterium tuberculosis

Para-aminosalicylic acid (PAS) is an antibiotic that was largely used for the multi-therapy of tuberculosis in the twentieth century. To try to overcome the inconvenience of its low efficacy and poor tolerance, we searched for novel chemical entities able to synergize with PAS using a combination screening against growing axenic Mycobacterium tuberculosis. The screening was performed at a sub-inhibitory concentration of PAS on a library of about 100,000 small molecules. Selected hit compounds were analyzed by dose–response and further probed with an intracellular macrophage assay. Scaffolds with potential additive effect with PAS are reported, opening interesting prospects for mechanism of action studies. We also report here evidence of a yet unknown bio-activation mechanism, involving activation of pyrido[1,2-a]pyrimidin-4-one (PP) derivatives through the Rv3087 protein.

Drug-like molecules with anti-trypanothione synthetase activity identified by high throughput screening

Trypanothione synthetase (TryS) catalyses the synthesis of N¹,N⁸-bis(glutathionyl)spermidine (trypanothione), which is the main low molecular mass thiol supporting several redox functions in trypanosomatids. TryS attracts attention as molecular target for drug development against pathogens causing severe and fatal diseases in mammals. A drug discovery campaign aimed to identify and characterise new inhibitors of TryS with promising biological activity was conducted. A large compound library (n = 51,624), most of them bearing drug-like properties, was primarily screened against TryS from Trypanosoma brucei (TbTryS). With a true-hit rate of 0.056%, several of the TbTryS hits (IC₅₀ from 1.2 to 36 µM) also targeted the homologue enzyme from Leishmania infantum and Trypanosoma cruzi (IC₅₀ values from 2.6 to 40 µM). Calmidazolium chloride and Ebselen stand out for their multi-species anti-TryS activity at low µM concentrations (IC₅₀ from 2.6 to 13.8 µM). The moieties carboxy piperidine amide and amide methyl thiazole phenyl were identified as novel TbTryS inhibitor scaffolds. Several of the TryS hits presented one-digit µM EC₅₀ against T. cruzi and L. donovani amastigotes but proved cytotoxic against the human osteosarcoma and macrophage host cells (selectivity index ≤ 3). In contrast, seven hits showed a significantly higher selectivity against T. b. brucei (selectivity index from 11 to 182). Non-invasive redox assays confirmed that Ebselen, a multi-TryS inhibitor, induces an intracellular oxidative milieu in bloodstream T. b. brucei. Kinetic and mass spectrometry analysis revealed that Ebselen is a slow-binding inhibitor that modifies irreversible a highly conserved cysteine residue from the TryS’s synthetase domain. The most potent TbTryS inhibitor (a singleton containing an adamantine moiety) exerted a non-covalent, non-competitive (with any of the substrates) inhibition of the enzyme. These data feed the drug discovery pipeline for trypanosomatids with novel and valuable information on chemical entities with drug potential.

Executive function moderates the relationship between temperament and psychological difficulties in middle childhood

The current study examined the possible moderating influence of hot and cool executive function (EF) on the relationship between temperament and psychological difficulties in middle childhood. One hundred and twenty-six children and their parents (n = 105) participated. Children aged between 5 and 12 years completed three hot (motivational decision-making on the Cambridge Gambling Task (CGT), delayed gratification, and Theory of Mind [ToM]) and three cool EF (working memory, inhibition, and attentional set shifting) measures. Children's parents completed the Behavioral Inhibition Sensitivity (BIS) and Behavioral Approach Sensitivity (BAS) Scale and the Strengths and Difficulties Questionnaire. Hot EF (CGT, ToM) exacerbated the relationship between BAS and externalizing problems. Neither hot nor cool EF moderated the relationship between BIS and internalizing problems. The current findings provide further evidence of a hot-cool distinction in EF in middle childhood, suggesting that these constructs should be investigated separately when assessing EF. In addition, by considering potential interactions between temperament and EF, clinicians/researchers may be able to predict broad categories of psychological problems in middle childhood.

Correlation between Reactogenicity and Immunogenicity after the ChAdOx1 nCoV-19 and BNT162b2 mRNA Vaccination

Correlation between vaccine reactogenicity and immunogenicity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unclear. Thus, we investigated to determine whether the reactogenicity after coronavirus disease 2019 vaccination is associated with antibody (Ab) titers and T cell responses. This study was prospective cohort study done with 131 healthcare workers at tertiary center in Seoul, South Korea. The degrees of the local reactions after the 1st and 2nd doses of ChAdOx1 nCov-19 (ChAdOx1) vaccination were significantly associated with the S1-specific IgG Ab titers (p=0.003 and 0.01, respectively) and neutralizing Ab (p=0.04 and 0.10, respectively) in age- and sex-adjusted multivariate analysis, whereas those after the BNT162b2 vaccination did not show significant associations. T cell responses did not show significant associations with the degree of reactogenicity after the ChAdOx1 vaccination or the BNT162b2 vaccination. Thus, high degree of local reactogenicity after the ChAdOx1 vaccine may be used as an indicator of strong humoral immune responses against SARS-CoV-2.

Immune responses to the ChAdOx1 nCoV-19 and BNT162b2 vaccines and to natural COVID-19 infections over a three-month period

BACKGROUND

There are limited data directly comparing immune responses to vaccines and to natural infections with COVID-19. This study assessed the immunogenicity of the BNT162b2 and ChAdOx1 nCoV-19 vaccines over a 3-month period and compared the immune responses with those to natural infections.

METHOD

We enrolled healthcare workers (HCWs) who received BNT162b2 or ChAdOx1 nCoV-19 vaccines and COVID-19-confirmed patients, and then S1-IgG and neutralizing antibodies and T cell responses were measured.

RESULTS

A total of 121 vaccinees and 26 patients with confirmed COVID-19 were analyzed. After the 2 nd dose, the BNT162b2 vaccine yielded S1-IgG antibody responses similar to natural infections (2241 ± 899 vs. 2601 ± 5039, p=0.676), but significantly stronger than the ChAdOx1 vaccine (174 ± 96, p <0.0001). The neutralizing antibody titer generated by BNT162b2 was 6-fold higher than that generated by ChAdOx1, but lower than that by natural infection. T cell responses persisted for the 3 months in the BNT162b2 and natural infection but decreased in the ChAdOx1.

CONCLUSIONS

Antibody responses after the 2 nd dose of BNT162b2 are higher than after the 2 nd dose of ChAdOx1 and like those occurring after natural infection. T cell responses are maintained longer in BNT162b2 vaccinees than in ChAdOx1 vaccinees.

A High-Content Screen for C/EBPα Expression Identifies Novel Therapeutic Agents in Dedifferentiated Liposarcoma

PURPOSE

Dedifferentiated liposarcoma (DDLS), one of the most common and aggressive sarcomas, infrequently responds to chemotherapy. DDLS survival and growth depend on underexpression of C/EBPα, a tumor suppressor and transcriptional regulator controlling adipogenesis. We sought to screen and prioritize candidate drugs that increase C/EBPα expression and may therefore serve as differentiation-based therapies for DDLS.

EXPERIMENTAL DESIGN

We screened known bioactive compounds for the ability to restore C/EBPα expression and inhibit proliferation selectively in two DDLS cell lines but not in normal adipose-derived stem cells (ASC). Selected hits' activity was validated, and the mechanism of the most potent, SN-38, was investigated. The in vivo efficacy of irinotecan, the prodrug of SN-38, was evaluated in DDLS xenograft models.

RESULTS

Of 3,119 compounds, screen criteria were met by 19. Validation experiments confirmed the DDLS selectivity of deguelin, emetine, and SN-38 and showed that they induce apoptosis in DDLS cells. SN-38 had the lowest IC₅₀ (approximately 10 nmol/L), and its pro-apoptotic effects were countered by knockdown of CEBPA but not of TP53. Irinotecan significantly inhibited tumor growth at well-tolerated doses, induced nuclear expression of C/EBPα, and inhibited HIF1α expression in DDLS patient-derived and cancer cell line xenograft models. In contrast, doxorubicin, the most common treatment for nonresectable DDLS, reduced tumor growth by 30% to 50% at a dose that caused weight loss.

CONCLUSIONS

This high-content screen revealed potential treatments for DDLS. These include irinotecan, which induces apoptosis of DDLS cells in a C/EBPα-dependent, p53-independent manner, and should be clinically evaluated in patients with advanced DDLS.

Comparison of Antibody and T Cell Responses Induced by Single Doses of ChAdOx1 nCoV-19 and BNT162b2 Vaccines

There are limited data directly comparing humoral and T cell responses to the ChAdOx1 nCoV-19 and BNT162b2 vaccines. We compared Ab and T cell responses after first doses of ChAdOx1 nCoV-19 vs. BNT162b2 vaccines. We enrolled healthcare workers who received ChAdOx1 nCoV-19 or BNT162b2 vaccine in Seoul, Korea. Anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S1 protein-specific IgG Abs (S1-IgG), neutralizing Abs (NT Abs), and SARS-CoV-2-specific T cell response were evaluated before vaccination and at 1-wk intervals for 3 wks after vaccination. A total of 76 persons, comprising 40 injected with the ChAdOx1 vaccine and 36 injected with the BNT162b2 vaccine, participated in this study. At 3 wks after vaccination, the mean levels (±SD) of S1-IgG and NT Abs in the BNT162b2 participants were significantly higher than in the ChAdOx1 participants (S1-IgG, 14.03±7.20 vs. 6.28±8.87, p<0.0001; NT Ab, 183.1±155.6 vs. 116.6±116.2, p=0.035), respectively. However, the mean values of the T cell responses in the 2 groups were comparable after 2 wks. The humoral immune response after the 1st dose of BNT162b2 developed faster and was stronger than after the 1st dose of ChAdOx1. However, the T cell responses to BNT162b2 and ChAdOx1 were similar.

Anti-Cancer Effect of Moroccan Cobra Naja haje Venom and Its Fractions against Hepatocellular Carcinoma in 3D Cell Culture

Hepatocellular carcinoma (HCC) is the most common primary liver cancer in adults, the fifth most common malignancy worldwide and the third leading cause of cancer related death. An alternative to the surgical treatments and drugs, such as sorafenib, commonly used in medicine is necessary to overcome this public health problem. In this study, we determine the anticancer effect on HCC of Moroccan cobra Naja haje venom and its fraction obtained by gel filtration chromatography against Huh7.5 cancer cell line. Cells were grown together with WI38 human fibroblast cells, LX2 human hepatic stellate cell line, and human endothelial cells (HUVEC) in MCTS (multi-cellular tumor spheroids) models. The hepatotoxicity of venom and its fractions were also evaluated using the normal hepatocytes cell line (Fa2N-4 cells). Our results showed that an anti HCC activity of Moroccan cobra Naja haje venom and, more specifically, the F7 fraction of gel filtration chromatography exhibited the greatest anti-hepatocellular carcinoma effect by decreasing the size of MCTS. This effect is associated with a low toxicity against normal hepatocytes. These results strongly suggest that the F7 fraction of Moroccan cobra Naja haje venom obtained by gel filtration chromatography possesses the ability to inhibit cancer cells proliferation. More research is needed to identify the specific molecule(s) responsible for the anticancer effect and investigate their mechanism of action.

Identification of hepatic fibrosis inhibitors through morphometry analysis of a hepatic multicellular spheroids model

A chronic, local inflammatory milieu can cause tissue fibrosis that results in epithelial-to-mesenchymal transition (EMT), endothelial-to-mesenchymal transition (EndMT), increased abundance of fibroblasts, and further acceleration of fibrosis. In this study, we aimed to identify potential mechanisms and inhibitors of fibrosis using 3D model-based phenotypic screening. We established liver fibrosis models using multicellular tumor spheroids (MCTSs) composed of hepatocellular carcinoma (HCC) and stromal cells such as fibroblasts (WI38), hepatic stellate cells (LX2), and endothelial cells (HUVEC) seeded at constant ratios. Through high-throughput screening of FDA-approved drugs, we identified retinoic acid and forskolin as candidates to attenuate the compactness of MCTSs as well as inhibit the expression of ECM-related proteins. Additionally, retinoic acid and forskolin induced reprogramming of fibroblast and cancer stem cells in the HCC microenvironment. Of interest, retinoic acid and forskolin had anti-fibrosis effects by decreasing expression of α-SMA and F-actin in LX2 cells and HUVEC cells. Moreover, when sorafenib was added along with retinoic acid and forskolin, apoptosis was increased, suggesting that anti-fibrosis drugs may improve tissue penetration to support the efficacy of anti-cancer drugs. Collectively, these findings support the potential utility of morphometric analyses of hepatic multicellular spheroid models in the development of new drugs with novel mechanisms for the treatment of hepatic fibrosis and HCCs.

A new high-content screening assay of the entire hepatitis B virus life cycle identifies novel antivirals

Background & Aims

Chronic hepatitis B is an incurable disease. Addressing the unmet medical need for therapies has been hampered by a lack of suitable cell culture models to investigate the HBV life cycle in a single experimental setup. We sought to develop a platform suitable to investigate all aspects of the entire HBV life cycle.

Methods

HepG2-NTCPsec+ cells were inoculated with HBV. Supernatants of infected cells were transferred to naïve cells. Inhibition of infection was determined in primary and secondary infected cells by high-content imaging of viral and cellular factors. Novel antivirals were triaged in cells infected with cell culture- or patient-derived HBV and in stably virus replicating cells. HBV internalisation and target-based receptor binding assays were conducted.

Results

We developed an HBV platform, screened 2,102 drugs and bioactives, and identified 3 early and 38 late novel HBV life cycle inhibitors using infectious HBV genotype D. Two early inhibitors, pranlukast (EC₅₀ 4.3 μM; 50% cytotoxic concentration [CC₅₀] >50 μM) and cytochalasin D (EC₅₀ 0.07 μM; CC₅₀ >50 μM), and 2 late inhibitors, fludarabine (EC₅₀ 0.1 μM; CC₅₀ 13.4 μM) and dexmedetomidine (EC₅₀ 6.2 μM; CC₅₀ >50 μM), were further investigated. Pranlukast inhibited HBV preS1 binding, whereas cytochalasin D prevented the internalisation of HBV. Fludarabine inhibited the secretion of HBV progeny DNA, whereas dexmedetomidine interfered with the infectivity of HBV progeny. Patient-derived HBV genotype C was efficiently inhibited by fludarabine (EC₅₀ 0.08 μM) and dexmedetomidine (EC₅₀ 8.7 μM).

Conclusions

The newly developed high-content assay is suitable to screen large-scale drug libraries, enables monitoring of the entire HBV life cycle, and discriminates between inhibition of early and late viral life cycle events.

Lay summary

HBV infection is an incurable, chronic disease with few available treatments. Addressing this unmet medical need has been hampered by a lack of suitable cell culture models to study the entire viral life cycle in a single experimental setup. We developed an image-based approach suitable to screen large numbers of drugs, using a cell line that can be infected by HBV and produces large amounts of virus particles. By transferring viral supernatants from these infected cells to uninfected target cells, we could monitor the entire viral life cycle. We used this system to screen drug libraries and identified novel anti-HBV inhibitors that potently inhibit HBV in various phases of its life cycle. This assay will be an important new tool to study the HBV life cycle and accelerate the development of novel therapeutic strategies.

•

We developed a high-content screening assay suitable to monitor the entire HBV life cycle and eligible to discriminate between early and late viral life cycle inhibition.

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We screened FDA-approved drugs and bioactives.

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We confirmed antiviral activity in primary and secondary assays, using stably virus replicating cells and cell culture- and patient-derived HBV.

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Novel HBV inhibitors prevent receptor binding, virus internalisation, replication, or egress of viral progeny.

Screening of FDA-Approved Drugs Using a MERS-CoV Clinical Isolate from South Korea Identifies Potential Therapeutic Options for COVID-19

Therapeutic options for coronaviruses remain limited. To address this unmet medical need, we screened 5406 compounds, including United States Food and Drug Administration (FDA)-approved drugs and bioactives, for activity against a South Korean Middle East respiratory syndrome coronavirus (MERS-CoV) clinical isolate. Among 221 identified hits, 54 had therapeutic indexes (TI) greater than 6, representing effective drugs. The time-of-addition studies with selected drugs demonstrated eight and four FDA-approved drugs which acted on the early and late stages of the viral life cycle, respectively. Confirmed hits included several cardiotonic agents (TI > 100), atovaquone, an anti-malarial (TI > 34), and ciclesonide, an inhalable corticosteroid (TI > 6). Furthermore, utilizing the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we tested combinations of remdesivir with selected drugs in Vero-E6 and Calu-3 cells, in lung organoids, and identified ciclesonide, nelfinavir, and camostat to be at least additive in vitro. Our results identify potential therapeutic options for MERS-CoV infections, and provide a basis to treat coronavirus disease 2019 (COVID-19) and other coronavirus-related illnesses.

A retrospective comparison of cognitive performance in individuals with advanced Parkinson's Disease in Hong Kong and Canada

A deeper understanding of the cross-cultural applicability of cognitive tests across countries and cultures is needed to better equip neuropsychologists for the assessment of patients from diverse backgrounds. Our study compared cognitive test scores in patients with advanced Parkinson's disease (PD) at the Prince of Wales Hospital (n = 63; Hong Kong) and the Foothills Medical Center (n = 20; Calgary, Canada). The groups did not differ in age or sex (p > .05), but Western patients had significantly more years of education (M = 14.2, SD = 2.7) than Asian patients (M = 10.33, SD = 4.4). Cognitive tests administered to both groups included: digit span, verbal fluency (animals), the Boston Naming Test, and verbal memory (California Verbal Learning Test or Chinese Auditory Verbal Learning Test). Testing was completed before and 12 months after deep brain stimulation surgery. Results showed cognitive performance was similar across time, but significant group differences were found on digit span forward (longer among patients from Hong Kong; F(1, 75) = 44.155, p < .001) and the Boston Naming Test (higher percent spontaneous correct among patients from Canada; F(1, 62) = 7.218, p = .009, η² = 0.104), after controlling for age, sex, and years of education. In conclusion, our findings provide preliminary support for the similarity of Chinese versions of tests originally developed for Western populations. Also, we caution that some aspects of testing may be susceptible to cultural bias and therefore warrant attention in clinical practice and refinement in future test development for Asian patients.

Views about sensory modulation from people with schizophrenia and treating staff: A multisite qualitative study

Introduction

Current non-pharmacological treatment options for people with schizophrenia are limited. There is, however, emerging evidence that sensory modulation can be beneficial for this population. This study aimed to gain insight into sensory modulation from the user’s and the treating staff’s perspectives.

Method

A qualitative content analysis design was used. Transcripts from occupational therapists ( n=11) and patients with schizophrenia ( n=13) derived from in-depth semi-structured interviews were analysed for themes using content analysis.

Results

Five themes emerged from this study: Service user education on the sensory approach is the key; A variety of tools should be tried; Sensory modulation provides a valued treatment option; There are challenges of managing perceived risk at an organisational level; and There is a shortage of accessible and effective training.

Conclusion

People with schizophrenia and treating staff had congruent perceptions regarding the use of sensory modulation as a treatment option. The findings suggest that sensory modulation can be a valued addition to treatment options for people with schizophrenia. We suggest further research on sensory modulation intervention effectiveness using quantitative methods so these results can be further explored.

Collaborative virtual screening to elaborate an imidazo[1,2-a]pyridine hit series for visceral leishmaniasis

An innovative pre-competitive virtual screening collaboration was engaged to validate and subsequently explore an imidazo[1,2-a]pyridine screening hit for visceral leishmaniasis. In silico probing of five proprietary pharmaceutical company libraries enabled rapid expansion of the hit chemotype, alleviating initial concerns about the core chemical structure while simultaneously improving antiparasitic activity and selectivity index relative to the background cell line. Subsequent hit optimization informed by the structure–activity relationship enabled by this virtual screening allowed thorough investigation of the pharmacophore, opening avenues for further improvement and optimization of the chemical series.

Ligand-based similarity screening of proprietary pharmaceutical company libraries enables rapid hit to lead investigation of a chemotype with anti-leishmania activity.

Discovery of thienothiazolocarboxamide analogues as novel anti-tubercular agent

In order to identify anti-tubercular agents with a novel scaffold, commercial libraries of small organic compounds were screened against a fluorescent strain of Mycobacterium tuberculosis H37Rv, using a dual phenotypic assay. Compounds were assessed against bacteria replicating in broth medium, as well as inside macrophages, and thienothiazolocarboxamide (TTCA) scaffold was identified as hit in both assays, with submicromolar inhibitory concentrations. Derivatives of TTCA were further synthesized and evaluated for their inhibitory effects on M.tuberculosis H37Rv. In the present study we report the structure-activity relationship of these TTCA derivatives. Compounds 28, 32 and 42 displayed good anti-tubercular activities, as well as favorable ADME and PK properties. Compound 42 exhibited excellent oral bioavailability in mice with high distribution to lungs, within 1 h. It was found to be efficacious in a dose dependent manner in a murine model of M. tuberculosis infection. Hence, compound 42 is now under evaluation as a potential lead candidate for treatment of tuberculosis.

Identification of Antiviral Drug Candidates against SARS-CoV-2 from FDA-Approved Drugs

Drug repositioning is the only feasible option to immediately address the COVID-19 global challenge. We screened a panel of 48 FDA-approved drugs against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which were preselected by an assay of SARS-CoV. We identified 24 potential antiviral drug candidates against SARS-CoV-2 infection. Some drug candidates showed very low 50% inhibitory concentrations (IC50s), and in particular, two FDA-approved drugs-niclosamide and ciclesonide-were notable in some respects.

Self-reported prospective memory after stroke

Prospective Memory (PM) is the memory for completing future intentions. This study aimed to compare self-reported PM of individuals with stroke to healthy controls, to determine if PM is impaired after stroke. Additionally, self-reported PM for individuals with stroke was compared to significant-other reports, ascertaining a level of self-awareness of PM function. Twenty-eight individuals with stroke, 25 significant-others, and 27 healthy controls completed the Brief Assessment of PM (BAPM) and the Prospective and Retrospective Memory Questionnaire (PRMQ) as part of a larger study. Individuals with stroke reported significantly more Basic Activities of Daily Living (BADL) PM failures compared to controls on Part A of the BAPM. On Part B, individuals with stroke reported BADL PM failures to be less problematic/important than controls, suggesting a lack of self-awareness into the consequences of PM failure. Individuals with stroke also reported significantly more PM and RM failures compared to controls on the PRMQ. No significant differences were found between individuals with stroke and their significant-others on both the BAPM and PRMQ. Results of this study helped to clarify the previous research and highlighted that individuals with stroke reported more PM failures than controls but underestimated the importance of such memory lapses.

Identification of inhibitors of Bcl-2 family protein-protein interaction by combining the BRET screening platform with virtual screening

Bcl-2 family proteins play key roles in tumor initiation, progression, and resistance to therapy. Therefore, the protein-protein interactions (PPIs) between the pro-survival proteins, B-cell lymphoma (Bcl)-2 and Bcl-xL, and the pro-apoptotic proteins, Bax and Bak, could be attractive therapeutic targets for anti-cancer drug discovery. Here, we found new small molecules, BIP-A1001 and BIP-A2001 that modulated Bak/Bax and Bcl-xL interactions by combining the Nanoluc/YFP-based bioluminescence resonance energy transfer (BRET) assay with structure based virtual screening. In addition, we chose compounds with similar structures to BIP-A1001 and BIP-A2001 and tested their inhibitory effects using the BRET assay as a dose-response function. The results indicated that identifying compounds that inhibit interactions between Bak/Bax and Bcl-xL could be a promising approach to enhance cancer therapy.

In Vitro and in Vivo Activity of mTOR Kinase and PI3K Inhibitors Against Leishmania donovani and Trypanosoma brucei

Kinetoplastid parasites, including Leishmania and Trypanosoma spp., are life threatening pathogens with a worldwide distribution. Next-generation therapeutics for treatment are needed as current treatments have limitations, such as toxicity and drug resistance. In this study, we examined the activities of established mammalian target of rapamycin (mTOR)/phosphoinositide 3-kinase (PI3K) inhibitors against these tropical diseases. High-throughput screening of a library of 1742 bioactive compounds against intracellular L. donovani was performed, and seven mTOR/PI3K inhibitors were identified. Dose-dilution assays revealed that these inhibitors had half maximal effective concentration (EC₅₀₎ values ranging from 0.14 to 13.44 μM for L. donovani amastigotes and from 0.00005 to 8.16 μM for T. brucei. The results of a visceral leishmaniasis mouse model indicated that treatment with Torin2, dactolisib, or NVP-BGT226 resulted in reductions of 35%, 53%, and 54%, respectively, in the numbers of liver parasites. In an acute T. brucei mouse model using NVP-BGT226 parasite numbers were reduced to under the limits of detection by five consecutive days of treatment. Multiple sequence and structural alignment results indicated high similarities between mTOR and kinetoplastid TORs; the inhibitors are predicted to bind in a similar manner. Taken together, these results indicated that the TOR pathways of parasites have potential for the discovery of novel targets and new potent inhibitors.

Inhibitors of Na+/K+ ATPase exhibit antitumor effects on multicellular tumor spheroids of hepatocellular carcinoma

Hepatocellular carcinoma (HCC), one of the most common malignant cancers worldwide, is associated with substantial mortality. Because HCCs have strong resistance to conventional chemotherapeutic agents, novel therapeutic strategies are needed to improve survival in patients with HCC. The multicellular tumor spheroid (MCTS) model is a powerful method for anticancer research because of its ability to mimic the complexity and heterogeneity of tumor tissue, the three-dimensional cellular context of tumor tissue, and the pathophysiological gradients of in vivo tumors. However, it is difficult to obtain meaningful results from the MCTS model without considering the conditions of clinical tumors. We, therefore, provided a proof of concept to determine whether spheroid models simulate in vivo tumor microenvironments. Through a high-throughput screening for HCC therapy using the MCTS model, we selected inhibitors of Na⁺/K⁺-ATPase (ouabain and digoxin) that could suppress cell growth and migration via inhibition of the epithelial-mesenchymal transition of HCC in vivo and in vitro. The results showed that this model provides a new paradigm for high-throughput drug screening and will significantly improve the efficiency of identifying new drugs for HCC treatment. Through utilization of MCTS models, here we found that inhibitors of Na⁺/K⁺-ATPase may be feasible as a novel target to sensitize HCC cells.

Responses to academic stress mediate the association between sleep difficulties and depressive/anxiety symptoms in Chinese adolescents

OBJECTIVE

Sleep difficulties are pervasive in Chinese adolescents, which exert aversive influence on their emotional health. However, the underlying mechanisms of this effect remain unclear. This study addressed whether stress responses mediate the concurrent and prospective relationship between sleep difficulties and depressive/anxiety symptoms in Chinese adolescents.

METHOD

17,946 adolescents (14-18 years-old) were administrated the Pittsburgh Sleep Quality Index, the Center for Epidemiologic Studies Depression Scale, Revised Children's Manifest Anxiety Scale and the Responses to Stress Questionnaire. Further, 710 of them finished the one-year follow-up assessments. Structural equation models were conducted to determine the concurrent and prospective mediation effects of stress responses and the moderated effect of gender and age.

RESULTS

Involuntary engagement and disengagement responses, as well as engagement coping, significantly mediated the cross-sectional relationship between sleep difficulties and depressive/anxiety symptoms. Moreover, sleep difficulties at baseline predicted enhanced involuntary engagement responses but reduced the use of engagement coping strategies one year later, resulting in an elevated level of depressive/anxiety symptoms. Finally, females and younger adolescents with greater sleep difficulties were more likely to generate maladaptive stress responses.

LIMITATIONS

First, sleep difficulties were only measured using self-reported approaches. Second, potential confounding variables (e.g., socioeconomic status) were not adjusted for. Third, our study only focused on typically-developing youth samples rather than clinical samples.

CONCLUSIONS

Our findings highlight the important role of stress responses in the relationship between sleep difficulties and depressive/anxiety symptoms. The findings might also shed some light on the psychological intervention of sleep difficulties and mood disorder in adolescent populations.

Common Nodes of Virus-Host Interaction Revealed Through an Integrated Network Analysis

Viruses are one of the major causes of acute and chronic infectious diseases and thus a major contributor to the global burden of disease. Several studies have shown how viruses have evolved to hijack basic cellular pathways and evade innate immune response by modulating key host factors and signaling pathways. A collective view of these multiple studies could advance our understanding of virus-host interactions and provide new therapeutic perspectives for the treatment of viral diseases. Here, we performed an integrative meta-analysis to elucidate the 17 different host-virus interactomes. Network and bioinformatics analyses showed how viruses with small genomes efficiently achieve the maximal effect by targeting multifunctional and highly connected host proteins with a high occurrence of disordered regions. We also identified the core cellular process subnetworks that are targeted by all the viruses. Integration with functional RNA interference (RNAi) datasets showed that a large proportion of the targets are required for viral replication. Furthermore, we performed an interactome-informed drug re-purposing screen and identified novel activities for broad-spectrum antiviral agents against hepatitis C virus and human metapneumovirus. Altogether, these orthogonal datasets could serve as a platform for hypothesis generation and follow-up studies to broaden our understanding of the viral evasion landscape.

Efficient long-term amplification of hepatitis B virus isolates after infection of slow proliferating HepG2-NTCP cells

BACKGROUND & AIMS

As hepatitis B virus (HBV) spreads through the infected liver it is simultaneously secreted into the blood. HBV-susceptible in vitro infection models do not efficiently amplify viral progeny or support cell-to-cell spread. We sought to establish a cell culture system for the amplification of infectious HBV from clinical specimens.

METHODS

An HBV-susceptible sodium-taurocholate cotransporting polypeptide-overexpressing HepG2 cell clone (HepG2-NTCPsec+) producing high titers of infectious progeny was selected. Secreted HBV progeny were characterized by native gel electrophoresis and electron microscopy. Comparative RNA-seq transcriptomics was performed to quantify the expression of host proviral and restriction factors. Viral spread routes were evaluated using HBV entry- or replication inhibitors, visualization of viral cell-to-cell spread in reporter cells, and nearest neighbor infection determination. Amplification kinetics of HBV genotypes B-D were analyzed.

RESULTS

Infected HepG2-NTCPsec+ secreted high levels of large HBV surface protein-enveloped infectious HBV progeny with typical appearance under electron microscopy. RNA-seq transcriptomics revealed that HBV does not induce significant gene expression changes in HepG2-NTCPsec+, however, transcription factors favoring HBV amplification were more strongly expressed than in less permissive HepG2-NTCPsec-. Upon inoculation with HBV-containing patient sera, rates of infected cells increased from 10% initially to 70% by viral spread to adjacent cells, and viral progeny and antigens were efficiently secreted. HepG2-NTCPsec+ supported up to 1,300-fold net amplification of HBV genomes depending on the source of virus. Viral spread and amplification were abolished by entry and replication inhibitors; viral rebound was observed after inhibitor discontinuation.

CONCLUSIONS

The novel HepG2-NTCPsec+ cells efficiently support the complete HBV life cycle, long-term viral spread and amplification of HBV derived from patients or cell culture, resembling relevant features of HBV-infected patients.

LAY SUMMARY

Currently available laboratory systems are unable to reproduce the dynamics of hepatitis B virus (HBV) spread through the infected liver and release into the blood. We developed a slowly dividing liver-derived cell line which multiplies infectious viral particles upon inoculation with patient- or cell culture-derived HBV. This new infection model can improve therapy by measuring, in advance, the sensitivity of a patient's HBV strain to specific antiviral drugs.

Next-Generation Phenotypic Screening in Early Drug Discovery for Infectious Diseases

Cell-based phenotypic screening has proven to be valuable, notably in recapitulating relevant biological conditions, for example, the host cell/pathogen niche. However, the corresponding methodological complexity is not readily compatible with high-throughput pipelines, and fails to inform either molecular target or mechanism of action, which frustrates conventional drug-discovery roadmaps. We review the state-of-the-art and emerging technologies that suggest new strategies for harnessing value from the complexity of phenotypic screening and augmenting powerful utility for translational drug discovery. Advances in cellular, molecular, and bioinformatics technologies are converging at a cutting edge where the complexity of phenotypic screening may no longer be considered a hinderance but rather a catalyst to chemotherapeutic discovery for infectious diseases.

High-resolution quantitative acoustic microscopy of cutaneous carcinoma and melanoma: Comparison with histology

BACKGROUND

The increased incidence rate of skin cancers during the last decades is alarming. One of the significant difficulties in the histopathology of skin cancers is appearance variability due to the heterogeneity of diseases or tissue preparation and staining process. This study aims to investigate whether the high-resolution acoustic microscopy has the potential for identifying and quantitatively classifying skin cancers.

MATERIAL/METHODS

Unstained standard formalin-fixed skin tissue samples were used for ultrasonic examination. The high-frequency acoustic microscope equipped with the 320 MHz transducer was utilized to visualize skin structure. Fourier transform was performed to calculate the sound speed and attenuation in the tissue.

RESULTS

The acoustic images demonstrate good concordance with the traditional histology images. All histological features in the tumour were easily identifiable on acoustic images. Each skin cancer type has its combination of ultrasonic properties significantly different from the healthy skin.

CONCLUSIONS

High-resolution acoustic imaging strengthened with quantitative analysis shows a potential to work as an auxiliary imaging modality assisting pathologists to lean to the particular decision in doubtful cases. The method can also assist surgeon to ensure the complete resection of a tumour.

Using a therapeutic companion robot for dementia symptoms in long-term care: reflections from a cluster-RCT

OBJECTIVES

We undertook a cluster-randomised controlled trial exploring the effect of a therapeutic companion robot (PARO) compared to a look-alike plush toy and usual care on dementia symptoms of long-term care residents. Complementing the reported quantitative outcomes , this paper provides critical reflection and commentary on individual participant responses to PARO, observed through video recordings , with a view to informing clinical practice and research.

METHOD

A descriptive, qualitative design with five participants selected from the PARO intervention arm of the trial. The trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12614000508673).

RESULTS

The five participants and their responses to PARO are presented in terms of three issues: i.) Different pre-intervention clinical presentations and different responses; ii.) Same individual, different response - the need for continual assessment and review; and iii.) The ethics of giving and retrieving PARO. Implications for clinical practice and future research are discussed in relation to each issue.

CONCLUSION

The findings suggest that one approach does not fit all, and that there is considerable variation in responses to PARO. A number of recommendations are discussed to aid the delivery of psychosocial interventions with PARO in practice, as well as to guide future research.

Identification of radiation-induced EndMT inhibitors through cell-based phenomic screening

Radiation‐induced pulmonary fibrosis (RIPF) triggers physiological abnormalities. Endothelial‐to‐mesenchymal transition (EndMT) is the phenotypic conversion of endothelial cells to fibroblast‐like cells and is involved in RIPF. In this study, we established a phenomic screening platform to measure radiation‐induced stress fibers and optimized the conditions for high‐throughput screening using human umbilical vein endothelial cells (HUVECs) to develop compounds targeting RIPF. The results of screening indicated that CHIR‐99021 reduced radiation‐induced fibrosis, as evidenced by an enlargement of cell size and increases in actin stress fibers and α‐smooth muscle actin expression. These effects were elicited without inducing serious toxicity in HUVECs, and the cytotoxic effect of ionizing radiation (IR) in nonsmall cell lung cancer was also enhanced. These results demonstrate that CHIR‐99021 enhanced the effects of IR therapy by suppressing radiation‐induced EndMT in lung cancer.

Enhancing Dignity for Older Inpatients: The Photograph-Next-to-the-Bed Study

OBJECTIVES

Older inpatients compromised by illness and cognitive decline may be stripped of physical and cultural identifiers, making them vulnerable to erosion of dignity. This study explored the experiences of patients, carers and clinical staff in response to a simple intervention that could enhance the dignity of care for older inpatients.

METHODS

All patients in a rehabilitation ward were encouraged to have a photograph of themselves next to their bed. Of those who participated, focus groups were recruited for patients, family members and staff to explore their reflections. Discussions were transcribed and analyzed using a deductive approach to capture evolving themes relating to patient care.

RESULTS

All groups reported that the photograph provided "connection" and means of communication between patients and staff. Staff spoke positively of gaining additional insights into patients' lives. Benefits included enrichment of inter-personal relationships between patients and staff, between staff and families and between patients themselves.

CONCLUSIONS

A bedside photograph improved connections between staff, patients and carers, promoting patients' dignity of identity.

CLINICAL IMPLICATIONS

Displaying a bedside photograph as a visual reminder of the patient in the pre‑illness state helps preservation of an individual's dignity, a core concept in patient‑centered care.

Identification of Antipneumococcal Molecules Effective Against Different Streptococcus pneumoniae Serotypes Using a Resazurin-Based High-Throughput Screen

Streptococcus pneumoniae is a major human pathogen, causing around 1.6 million deaths worldwide each year. By optimizing a resazurin-based assay to detect S. pneumoniae growth in 384-well microplates, we developed a new high-throughput screening (HTS) system for the discovery of antipneumococcal molecules, which was unsuccessful using conventional absorbance measurements. Before applying our protocol to a large-scale screen, we validated the system through a pilot screen targeting about 7,800 bioactive molecules using three different S. pneumoniae serotypes. Primary screenings of a further 27,000 synthetic small molecules facilitated the identification of 3-acyl-2-phenylamino-1,4-dihydropquinolin-4-one (APDQ) derivatives that inhibited growth of S. pneumoniae with MIC₉₀ values <1 μM (0.03-0.81 μM). Five selected APDQ derivatives were also active against Staphylococcus aureus but neither Klebsiella pneumoniae nor Pseudomonas aeruginosa, suggesting that APDQ may act specifically against Gram-positive bacteria. Our results both validated and demonstrated the utility of the resazurin-based HTS system for the identification of new antipneumococcal molecules. Moreover, the identified new antipneumococcal molecules in this study may have potential to be further developed as new antibiotics.

Does Cognitive Impairment and Agitation in Dementia Influence Intervention Effectiveness? Findings From a Cluster-Randomized-Controlled Trial With the Therapeutic Robot, PARO

OBJECTIVES

To explore whether severity of cognitive impairment and agitation of older people with dementia predict outcomes in engagement, mood states, and agitation after a 10-week intervention with the robotic seal, PARO.

DESIGN

Data from the PARO intervention-arm of a cluster-randomized controlled trial was used, which involved individual, nonfacilitated, 15-minute sessions with PARO 3 afternoons per week for 10 weeks.

SAMPLE AND PARTICIPANTS

One hundred thirty-eight residents-aged ≥60 years, with dementia-from 9 long-term care facilities.

MEASURES

A series of stepwise multiple linear regressions were conducted. Dependent variables were participants' levels of engagement, mood states, and agitation at week 10 [assessed by video observation and Cohen Mansfield Agitation Inventory-Short Form (CMAI-SF)]. Predictor variables were baseline levels of cognitive impairment [assessed by Rowland Universal Dementia Assessment Scale (RUDAS)] and agitation (CMAI-SF).

RESULTS

Five models were produced. The strongest finding was that participants with more severe agitation at baseline had higher levels of agitation at week 10 (R² = .82, P < .001). Predictors of positive response were less significant. Low levels of agitation at baseline predicted greater positive behavioral engagement with PARO (R² = .054, P = .009) and fewer observed instances of agitation (R² = .033, P = .045) at week 10, whereas greater visual engagement was predicted by both lower levels of agitation and cognitive impairment (R² = .082, P = .006). Less severe cognitive impairment predicted greater pleasure at week 10 (R² = .067, P = .004).

CONCLUSIONS/IMPLICATIONS

Participants with severe agitation had poor response to PARO. Lower levels of agitation and higher cognitive functioning were associated with better responses. In clinical practice, we recommend PARO should be restricted to people with low-moderate severity of agitation. Further research is needed to determine the optimal participant characteristics for response to PARO.

Health Care Workers' Experiences of Aggression

PRIMARY OBJECTIVE

To identify the prevalence of patient aggression against health care workers, the consequences and coping mechanisms.

DESIGN

Retrospective cross-sectional design.

SUBJECTS

50 participants comprised 37 nurses, 1 ward staff, 12 allied health staff employed in two brain injury wards with experience ranging from 3months to 34years.

SETTING

Neurosciences and Brain Injury Rehabilitation wards of a metropolitan tertiary hospital in Brisbane.

MAIN OUTCOME MEASURES

Researcher designed self-report questionnaire.

RESULTS

98% of respondents had experienced aggression during their health care careers with an average of 143.93 events. Physical injuries had been sustained by 40% of staff, psychological injury by 82%, but only 12% sought treatment. Verbal aggression related to receiving a psychological injury (r=0.305, p<0.05). Experiencing one type of aggression made it more likely the person would also experience the other types of aggression. Verbal aggression was correlated with physical aggression (r=0.429, p<0.01) and non-verbal aggression (r=0.286, p<0.05), and physical aggression was correlated with non-verbal aggression (r=0.333, p<0.05). The majority of staff used informal debriefing with others as their main coping strategy which was considered effective.

CONCLUSIONS

Patient aggression is prevalent and of serious concern for staff working in hospital settings.