The Natural History of Trisomy 21: Outcome Data from a Large Tertiary Referral Centre.

OBJECTIVE: The aim of the study was to prospectively gather data on pregnancy outcomes of prenatally diagnosed trisomy 21 (T21) in a large tertiary referral centre. METHODS: Data were gathered prospectively in a large tertiary referral centre over 5 years from 2013 to 2017 inclusively. Baseline demographic and pregnancy outcome data were recorded on an anonymized computerized database. RESULTS: There were 1,836 congenital anomalies diagnosed in the study period including 8.9% (n = 165) cases of T21. 79% (n = 131) were age 35 or older at diagnosis. 79/113 (69.9%) women chose a termination of pregnancy (TOP) following a diagnosis of T21. Amongst pregnancies that continued, there were 4 second-trimester miscarriages (4/34, 11.7%), 9 stillbirths (9/34, 26.4%), and 1 neonatal death, giving an overall pregnancy and neonatal loss rate of 14/34 (41.1%). CONCLUSION: The risk of foetal loss in prenatally diagnosed T21 is high at 38% with an overall pregnancy loss rate of 41.1%. This information may be of benefit when counselling couples who are faced with a diagnosis of T21 particularly in the context of limited access to TOP.

Generation of SARS-CoV-2 reporter replicon for high-throughput antiviral screening and testing.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research and antiviral discovery are hampered by the lack of a cell-based virus replication system that can be readily adopted without biosafety level 3 (BSL-3) restrictions. Here, the construction of a noninfectious SARS-CoV-2 reporter replicon and its application in deciphering viral replication mechanisms and evaluating SARS-CoV-2 inhibitors are presented. The replicon genome is replication competent but does not produce progeny virions. Its replication can be inhibited by RdRp mutations or by known SARS-CoV-2 antiviral compounds. Using this system, a high-throughput antiviral assay has also been developed. Significant differences in potencies of several SARS-CoV-2 inhibitors in different cell lines were observed, which highlight the challenges of discovering antivirals capable of inhibiting viral replication in vivo and the importance of testing compounds in multiple cell culture models. The generation of a SARS-CoV-2 replicon provides a powerful platform to expand the global research effort to combat COVID-19.

Discovery of an Anion-Dependent Farnesyltransferase Inhibitor from a Phenotypic Screen.

By employing a phenotypic screen, a set of compounds, exemplified by 1, were identified which potentiate the ability of histone deacetylase inhibitor vorinostat to reverse HIV latency. Proteome enrichment followed by quantitative mass spectrometric analysis employing a modified analogue of 1 as affinity bait identified farnesyl transferase (FTase) as the primary interacting protein in cell lysates. This ligand-FTase binding interaction was confirmed via X-ray crystallography and temperature dependent fluorescence studies, despite 1 lacking structural and binding similarity to known FTase inhibitors. Although multiple lines of evidence established the binding interaction, these ligands exhibited minimal inhibitory activity in a cell-free biochemical FTase inhibition assay. Subsequent modification of the biochemical assay by increasing anion concentration demonstrated FTase inhibitory activity in this novel class. We propose 1 binds together with the anion in the active site to inhibit farnesyl transferase. Implications for phenotypic screening deconvolution and HIV reactivation are discussed.

Discovery of Highly Selective and Potent HDAC3 Inhibitors Based on a 2-Substituted Benzamide Zinc Binding Group.

The selectivity of histone deacetylase inhibitors (HDACis) is greatly impacted by the zinc binding groups. In an effort to search for novel zinc binding groups, we applied a parallel medicinal chemistry (PMC) strategy to quickly synthesize substituted benzamide libraries. We discovered a series containing 2-substituted benzamides as the zinc binding group which afforded highly selective and potent HDAC3 inhibitors, exemplified by compound 16 with a 2-methylthiobenzamide. Compound 16 inhibited HDAC3 with an IC50 of 30 nM and with unprecedented selectivity of >300-fold over all other HDAC isoforms. Interestingly, a subtle change of the 2-methylthio to a 2-hydroxy benzamide in 20 retains HDAC3 potency but loses all selectivity over HDAC 1 and 2. This significant difference in selectivity was rationalized by X-ray crystal structures of HDACis 16 and 20 bound to HDAC2, revealing different binding modes to the catalytic zinc ion. This series of HDAC3 selective inhibitors served as tool compounds for investigating the minimal set of HDAC isoforms that must be inhibited for the HIV latency activation in a Jurkat 2C4 cell model and potentially as leads for selective HDAC3 inhibitors for other indications.

Identification of potent inhibitors of the sortilin-progranulin interaction.

High-throughput screening methods have been used to identify two novel series of inhibitors that disrupt progranulin binding to sortilin. Exploration of structure-activity relationships (SAR) resulted in compounds with sufficient potency and physicochemical properties to enable co-crystallization with sortilin. These co-crystal structures supported observed SAR trends and provided guidance for additional avenues for designing compounds with additional interactions within the binding site.

Selective Class I HDAC Inhibitors Based on Aryl Ketone Zinc Binding Induce HIV-1 Protein for Clearance.

HIV persistence in latently infected, resting CD4+ T cells is broadly considered a barrier to eradicate HIV. Activation of the provirus using latency-reversing agents (LRAs) followed by immune-mediated clearance to purge reservoirs has been touted as a promising therapeutic approach. Histone deacetylases (HDACs) and histone acetyltransferases (HATs) control the acetylation level of lysine residues in histones to regulate the gene transcription. Several clinical HDAC inhibitors had been examined as LRAs, which induced HIV activation in vitro and in vivo. Here we report the discovery of a series of selective and potent class I HDAC inhibitors based on aryl ketones as a zinc binding group, which reversed HIV latency using a Jurkat model of HIV latency in 2C4 cells. The SAR led to the discovery of a highly selective class I HDAC inhibitor 10 with excellent potency. HDACi 10 induces the HIV gag P24 protein in patient latent CD4+ T cells.

Discovery of MK-8718, an HIV Protease Inhibitor Containing a Novel Morpholine Aspartate Binding Group.

A novel HIV protease inhibitor was designed using a morpholine core as the aspartate binding group. Analysis of the crystal structure of the initial lead bound to HIV protease enabled optimization of enzyme potency and antiviral activity. This afforded a series of potent orally bioavailable inhibitors of which MK-8718 was identified as a compound with a favorable overall profile.

Development of a sensitive amplified luminescent proximity homogeneous assay to monitor the interactions between pTEFb and Tat.

The viral transactivator protein (Tat) plays an essential role in the replication of human immunodeficiency type 1 virus (HIV-1) by recruiting the host positive transcription elongation factor (pTEFb) to the RNA polymerase II transcription machinery to enable an efficient HIV-1 RNA elongation process. Blockade of the interaction between Tat and pTEFb represents a novel strategy for developing a new class of antiviral agents. In this study, we developed a homogeneous assay in AlphaLISA (amplified luminescent proximity homogeneous assay) format using His-tagged pTEFb and biotinylated Tat to monitor the interaction between Tat and pTEFb. On optimizing the assay conditions, the signal-to-background ratio was found to be greater than 10-fold. The assay was validated with untagged Tat and peptides known to compete with Tat for pTEFb binding. The Z' of the assay is greater than 0.5, indicating that the assay is robust and can be easily adapted to a high-throughput screening format. Furthermore, the affinity between Tat and pTEFb was determined to be approximately 20 pM, and only 7% of purified Tat was found to be active in forming tertiary complex with pTEFb. Development of this assay should facilitate the discovery of a new class of antiviral agents providing HIV-1 patients with broader treatment choices.

Chondroitin sulfate promotes activation of cathepsin K.

Cathepsin K (CatK), a major lysosomal collagenase produced by osteoclasts, plays an important role in bone resorption. Evidence exists that the collagenase activity of CatK is promoted by chondroitin sulfate (CS), a sulfated glycosaminoglycan. This study examines the role of CS in facilitating CatK activation. We have demonstrated that chondroitin 4-sulfate (C4-S) promotes autoprocessing of the pro-domain of CatK at pH ≤ 5, leading to a fully matured enzyme with collagenase and peptidase activities. We present evidence to demonstrate this autoactivation process is a trans-activation event that is efficiently inhibited by both the covalent cysteine protease inhibitor E-64 and the reversible selective CatK inhibitor L-006,235. During bone resorption, CatK and C4-S are co-localized at the ruffled border between osteoclast bone interface, supporting the proposal that CatK activation is accomplished through the combined action of the acidic environment together with the presence of a high concentration of C4-S. Formation of a multimeric complex between C4-S and pro-CatK has been speculated to accelerate CatK autoactivation and promote efficient collagen degradation. Together, these results demonstrate that CS plays an important role in contributing to the enhanced efficiency of CatK collagenase activity in vivo.

Does the addition of integrated cognitive behaviour therapy and motivational interviewing improve the outcomes of standard care for young people with comorbid depression and substance misuse?

OBJECTIVE: To determine whether the addition of cognitive behaviour therapy and motivational interviewing (CBT/MI) to standard alcohol and other drug (AOD) care improves outcomes for young people with comorbid depression and substance misuse. PARTICIPANTS AND SETTING: Participants were young people with comorbid depression (Kessler Psychological Distress Scale score ≥ 17) and substance misuse (mainly alcohol and/or cannabis) seeking treatment at two youth AOD services in Melbourne, Australia. The study was conducted between September 2006 and September 2008. Sixty young people received CBT/MI in addition to standard care (SC) (the SC+CBT/MI group) and 28 received SC only (the SC group). MAIN OUTCOME MEASURES: Depressive symptoms and AOD use in the previous 30 days, measured at baseline and at 3-month and 6-month follow-up. RESULTS: Compared with participants in the SC group, those in the SC+CBT/MI group showed significant reductions in depression and cannabis use and increased social contact and motivation to change substance use at 3-month follow-up. However, at 6-month follow-up, the SC group had achieved similar improvements to the CBT/MI group on these variables. All young people achieved significant improvements in functioning and quality of life variables over time, regardless of treatment group. No changes in AOD use were found in either group at 6-month follow-up. CONCLUSION: The delivery of CBT/MI in addition to SC may achieve accelerated treatment gains in the short term.

Outcomes of an integrated cognitive behaviour therapy (CBT) treatment program for co-occurring depression and substance misuse in young people.

BACKGROUND: There are high rates of co-occurring depression among young people with substance use disorders. While there is preliminary evidence for the effectiveness of integrated cognitive behaviour therapy (CBT) in combination with antidepressants among alcohol and substance dependent adolescents and adults with co-existing depression, no studies have examined the effectiveness of integrated CBT interventions in the absence of pharmacotherapy. The aim of the current study was to determine the outcomes of an integrated CBT intervention for co-occurring depression and substance misuse in young people presenting to a mental health setting. METHODS: Sixty young people (aged 15 to 25), with a DSM-IV diagnosis of Major Depressive Disorder and concurrent substance misuse (at least weekly use in the past month) or disorder were recruited from a public youth mental health service in Melbourne, Australia. Participants received 10 sessions of individual integrated CBT treatment delivered with case management over a 20-week period. RESULTS: The intervention was associated with significant improvements in depression, anxiety, substance use, coping skills, depressive and substance use cognitions and functioning at mid- (10 weeks) and post- (20 weeks) treatment. These changes were maintained at 6 months follow-up (44 weeks). CONCLUSIONS: These results provide preliminary evidence for the effectiveness of the integrated CBT intervention in young people with co-occurring depression and substance misuse. Further studies using randomised controlled designs are required to determine its efficacy.

Identification and biological evaluation of a series of 1H-benzo[de]isoquinoline-1,3(2H)-diones as hepatitis C virus NS5B polymerase inhibitors.

The hepatitis C virus (HCV) NS5B RNA-dependent RNA polymerase (RdRp) plays a central role in virus replication. NS5B has no functional equivalent in mammalian cells and, as a consequence, is an attractive target for inhibition. Herein, we present 1H-benzo[de]isoquinoline-1,3(2H)-diones as a new series of selective inhibitors of HCV NS5B polymerase. The HTS hit 1 shows submicromolar potency in two different HCV replicons (1b and 2b) and displays no activity on other polymerases (HIV-RT, Polio-pol, GBV-b-pol). These inhibitors act during the pre-elongation phase by binding to NS5B non-nucleoside binding site Thumb Site II as demonstrated by crystal structure of compound 1 with the DeltaC55-1b and DeltaC21-2b enzymes and by mutagenesis studies. SAR in this new series reveals inhibitors, such as 20, with low micromolar activity in the HCV replicon and with good activity/toxicity window in cells.

Integrated cognitive behaviour therapy for co-occurring substance misuse and major depression: lessons from a youth mental health service.

OBJECTIVE: The aim of this paper is to describe a 20-week integrated cognitive behavioural therapy (CBT) program addressing co-occurring substance misuse and major depression in young people. METHOD: Participants were aged between 15 and 25 years, met DSM-IV criteria for major depressive disorder and had at least weekly illicit drug use and/or weekly alcohol use exceeding the Australian national guidelines on alcohol. RESULTS: Between December 2004 and January 2007, an integrated CBT program was offered to 60 young people with co-occurring depression and substance misuse who presented to a youth-specific mental health service. Young people attended for a median of 10.5 sessions. CONCLUSIONS: We describe the components of a 20-week integrated CBT program for young people with co-occurring depression and comorbid substance misuse, as well as the challenges associated with providing such treatment. While integrated treatment approaches are recommended as best practice for this population, further evaluation is necessary to determine their effectiveness within routine clinical settings.