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1.
J Surg Res ; 298: 36-40, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38552588

ABSTRACT

INTRODUCTION: Readmissions after a traumatic brain injury (TBI) can have severe impacts on long-term health outcomes as well as rehabilitation. The aim of this descriptive study was to analyze the Nationwide Readmissions Database to determine possible risk factors associated with readmission for patients who previously sustained a TBI. METHODS: This retrospective study used data from the Nationwide Readmissions Database to explore gender, age, injury severity score, comorbidities, index admission hospital size, discharge disposition of the patient, and cause for readmission for adults admitted with a TBI. Multivariable logistic regression was used to assess likelihood of readmission. RESULTS: There was a readmission rate of 28.7% (n = 31,757) among the study population. The primary cause of readmission was either subsequent injury or sequelae of the original injury (n = 8825; 29%) followed by circulatory (n = 5894; 19%) and nervous system issues (n = 2904; 9%). There was a significantly higher risk of being readmitted in males (Female odds ratio: 0.87; confidence interval [0.851-0.922), older patients (65-79: 32.3%; > 80: 37.1%), patients with three or more comorbidities (≥ 3: 32.9%), or in patients discharged to a skilled nursing facility/intermediate care facility/rehab (SNF/ICF/Rehab odds ratio: 1.55; confidence interval [0.234-0.262]). CONCLUSIONS: This study demonstrates a large proportion of patients are readmitted after sustaining a TBI. A significant number of patients are readmitted for subsequent injuries, circulatory issues, nervous system problems, and infections. Although readmissions cannot be completely avoided, defining at-risk populations is the first step of understanding how to reduce readmissions.

2.
J Med Chem ; 67(2): 1115-1126, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38215028

ABSTRACT

The development of more effective drugs requires knowledge of their bioavailability and binding efficacy directly in the native cellular environment. In-cell nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for investigating ligand-target interactions directly in living cells. However, the target molecule may be NMR-invisible due to interactions with cellular components, while observing the ligand by 1H NMR is impractical due to the cellular background. Such limitations can be overcome by observing fluorinated ligands by 19F in-cell NMR as they bind to the intracellular target. Here we report a novel approach based on real-time in-cell 19F NMR that allows measuring ligand binding affinities in human cells by competition binding, using a fluorinated compound as a reference. The binding of a set of compounds toward Hsp90α was investigated. In principle, this approach could be applied to other pharmacologically relevant targets, thus aiding the design of more effective compounds in the early stages of drug development.


Subject(s)
Magnetic Resonance Imaging , Humans , Binding, Competitive , Ligands , Magnetic Resonance Spectroscopy/methods , Protein Binding , Fluorine/chemistry
3.
ACS Chem Neurosci ; 15(3): 671-684, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38238043

ABSTRACT

α1A-, α1B-, and α1D-adrenoceptors (α1-ARs) are members of the adrenoceptor G protein-coupled receptor family that are activated by adrenaline (epinephrine) and noradrenaline. α1-ARs are clinically targeted using antagonists that have minimal subtype selectivity, such as prazosin and tamsulosin, to treat hypertension and benign prostatic hyperplasia, respectively. Abundant expression of α1-ARs in the heart and central nervous system (CNS) makes these receptors potential targets for the treatment of cardiovascular and CNS disorders, such as heart failure, epilepsy, and Alzheimer's disease. Our understanding of the precise physiological roles of α1-ARs, however, and their involvement in disease has been hindered by the lack of sufficiently subtype-selective tool compounds, especially for α1B-AR. Here, we report the discovery of 4-[(2-hydroxyethyl)amino]-6-methyl-2H-chromen-2-one (Cpd1), as an α1B-AR antagonist that has 10-15-fold selectivity over α1A-AR and α1D-AR. Through computational and site-directed mutagenesis studies, we have identified the binding site of Cpd1 in α1B-AR and propose the molecular basis of α1B-AR selectivity, where the nonconserved V19745.52 residue plays a major role, with contributions from L3146.55 within the α1B-AR pocket. By exploring the structure-activity relationships of Cpd1 at α1B-AR, we have also identified 3-[(cyclohexylamino)methyl]-6-methylquinolin-2(1H)-one (Cpd24), which has a stronger binding affinity than Cpd1, albeit with reduced selectivity for α1B-AR. Cpd1 and Cpd24 represent potential leads for α1B-AR-selective drug discovery and novel tool molecules to further study the physiology of α1-ARs.


Subject(s)
Prazosin , Receptors, Adrenergic, alpha-1 , Receptors, Adrenergic, alpha-1/metabolism , Tamsulosin , Norepinephrine
4.
SLAS Discov ; 29(1): 40-51, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37714432

ABSTRACT

Surface plasmon resonance (SPR) biosensor methods are ideally suited for fragment-based lead discovery.  However, generally applicable experimental procedures and detailed protocols are lacking, especially for structurally or physico-chemically challenging targets or when tool compounds are not available. Success depends on accounting for the features of both the target and the chemical library, purposely designing screening experiments for identification and validation of hits with desired specificity and mode-of-action, and availability of orthogonal methods capable of confirming fragment hits. The range of targets and libraries amenable to an SPR biosensor-based approach for identifying hits is considerably expanded by adopting multiplexed strategies, using multiple complementary surfaces or experimental conditions. Here we illustrate principles and multiplexed approaches for using flow-based SPR biosensor systems for screening fragment libraries of different sizes (90 and 1056 compounds) against a selection of challenging targets. It shows strategies for the identification of fragments interacting with 1) large and structurally dynamic targets, represented by acetyl choline binding protein (AChBP), a Cys-loop receptor ligand gated ion channel homologue, 2) targets in multi protein complexes, represented by lysine demethylase 1 and a corepressor (LSD1/CoREST), 3) structurally variable or unstable targets, represented by farnesyl pyrophosphate synthase (FPPS), 4) targets containing intrinsically disordered regions, represented by protein tyrosine phosphatase 1B  (PTP1B), and 5) aggregation-prone proteins, represented by an engineered form of human tau  (tau K18M). Practical considerations and procedures accounting for the characteristics of the proteins and libraries, and that increase robustness, sensitivity, throughput and versatility are highlighted. The study shows that the challenges for addressing these types of targets is not identification of potentially useful fragments per se, but establishing methods for their validation and evolution into leads.


Subject(s)
Biosensing Techniques , Surface Plasmon Resonance , Humans , Surface Plasmon Resonance/methods , Small Molecule Libraries/pharmacology , Proteins , Carrier Proteins
5.
Cult Health Sex ; : 1-16, 2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37740584

ABSTRACT

This paper describes the strategies used by Aboriginal young people to build positive relationships and sexual wellbeing. It does so to counter the risk-focussed narratives present in much existing research and to showcase the resourcefulness of Aboriginal young people. We used peer-interview methods to collect qualitative data from 52 Aboriginal young people living in western Sydney, Australia. Participants reported a strong desire to stay safe and healthy in their sexual relationships and to achieve this they relied heavily on oral communication and yarning strategies. Participants viewed communication as a way to gain or give advice (about bodies, infections, pregnancy, relationships); to assess the acceptability and safety of potential partners; to negotiate consent with partners; to build positive relationships; and to get themselves out of unhealthy relationships. Participants also discussed 'self-talk' as a strategy for building sexual wellbeing, referring to narratives of self-respect and pride in culture as important in establishing Aboriginal young people's positive views of self and as deserving of respectful and safe sexual relationships. These findings suggest that future programmes and interventions based on yarning could be well-regarded, given it is a cultural form of pedagogy and a strategy Aboriginal young people already use to build positive relationships and identities.

6.
Front Vet Sci ; 10: 1228505, 2023.
Article in English | MEDLINE | ID: mdl-37601751

ABSTRACT

We describe a case of lumpy skin disease in an endangered banteng in Cambodia and the subsequent initiation of a vaccination campaign in domestic cattle to protect wild bovids from disease transmission at the wildlife-livestock interface. Lumpy skin disease virus (LSDV) was first detected in domestic cattle in Cambodia in June of 2021 and rapidly spread throughout the country. In September 2021, a banteng was seen in Phnom Tnout Phnom Pok wildlife sanctuary with signs of lumpy skin disease. Scab samples were collected and tested positive for LSDV. Monitoring using line transect surveys and camera traps in protected areas with critical banteng and gaur populations was initiated from December 2021-October 2022. A collaborative multisector vaccination campaign to vaccinate domestic livestock in and around priority protected areas with banteng and gaur was launched July 2022 and a total of 20,089 domestic cattle and water buffalo were vaccinated with LumpyvaxTM. No signs of LSDV in banteng or gaur in Cambodia have been observed since this initial case. This report documents the first case of lumpy skin disease in wildlife in Cambodia and proposes a potential intervention to mitigate the challenge of pathogen transmission at the domestic-wildlife interface. While vaccination can support local livestock-based economies and promote biodiversity conservation, it is only a component of an integrated solution and One Health approach to protect endangered species from threats at the wildlife-livestock interface.

7.
Cureus ; 15(7): e41292, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37539422

ABSTRACT

Multiple myeloma (MM) is a clonal plasma cell proliferative disorder characterized by the abnormal increase of monoclonal paraprotein and can lead to specific end-organ damage. Necrotizing enterocolitis or bowel necrosis is a surgical emergency defined by cellular death because of reduced blood flow to the gastrointestinal tract. We report a case of a 75-year-old female who was diagnosed with hyperviscosity syndrome (HVS) and was sent to ED. Further workup showed that she had a new diagnosis of IgG kappa MM for which she was started on chemotherapy. Later, she developed respiratory distress and abdomen distention with less frequent bowel movements, and general surgery was consulted. CT scan of the abdomen and pelvis with contrast showed findings consistent with bowel ischemia vs infarction. The patient was immediately taken to the operating room, and exploratory laparotomy showed nonsurvivable bowel necrosis. She was transitioned to comfort care and passed away later. We aim to increase awareness among physicians to include HVS as one of the possible complications of MM and to detect it early to prevent morbidity and mortality.

8.
Appl Biosaf ; 28(2): 96-101, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37342516

ABSTRACT

Introduction: Shigella bacteria cause shigellosis, a gastrointestinal infection most often acquired from contaminated food or water. Methods: In this review, the general characteristics of Shigella bacteria are described, cases of laboratory-acquired infections (LAIs) are discussed, and evidence gaps in current biosafety practices are identified. Results: LAIs are undoubtedly under-reported. Owing to the low infectious dose, rigorous biosafety level 2 practices are required to prevent LAIs resulting from sample manipulation or contact with infected surfaces. Conclusions: It is recommended that, before laboratory work with Shigella, an evidence-based risk assessment be conducted. Particular emphasis should be placed on personal protective equipment, handwashing, and containment practices for procedures that generate aerosols or droplets.

9.
PLoS One ; 18(4): e0283977, 2023.
Article in English | MEDLINE | ID: mdl-37018347

ABSTRACT

Although vaccination is widely considered one of the most cost-effective health interventions available, global coverage rates for many vaccines remain lower than necessary for disease elimination and eradication. New vaccine technologies can play an important role in addressing barriers to vaccination and increasing coverage rates. To identify and prioritize vaccine technology investments, decision makers must be able to compare the overall costs and benefits of each investment option. While these data points may exist, they are often confined to silos. Decision makers would benefit from a model that synthesizes this broad range of data and provides clear and actionable information. To facilitate vaccine investment, purchasing and deployment decisions, we developed a systematic and transparent cost-benefit model that estimates the value and risk of a given investment scenario from the perspective of both "buyers" (e.g., global donors, country governments) and "sellers" (e.g., developers, manufacturers) of vaccines. This model, which can be used to evaluate scenarios related to a single vaccine presentation or a portfolio of vaccine presentations, leverages our published approach for estimating the impact of improved vaccine technologies on vaccination coverage rates. This article presents a description of the model and provides an illustrative example application to a portfolio of measles-rubella vaccine technologies currently under development. Although the model is generally applicable to organizations involved in vaccine investment, manufacturing or purchasing, we believe it may be particularly useful to those engaged in vaccine markets that rely strongly on funding from institutional donors.


Subject(s)
Measles , Rubella , Humans , Cost-Benefit Analysis , Rubella/prevention & control , Measles/prevention & control , Measles Vaccine , Rubella Vaccine , Vaccination
10.
Glob Public Health ; 18(1): 2196561, 2023 01.
Article in English | MEDLINE | ID: mdl-37018760

ABSTRACT

Aboriginal and Torres Strait Islander (Aboriginal) young people seek information and access health services for their sexual health needs. This study examined Aboriginal young people's perspectives on sexual health services and sex education in Australia. Overall, 51 Aboriginal people aged 16-26 years were interviewed by peer researchers in Sydney, Australia in 2019-2020. The findings suggest that the internet was used to assess information quickly and confidentially, but Aboriginal young people questioned its reliability and accuracy. Family, Elders and peers were seen as sources of advice because they had real-life experience and highlighted intergenerational learning that occurs in Aboriginal communities. School-based sex education programmes had mixed reviews, with a preference for programmes delivered by external specialists providing anonymity, clear and accurate information about sex and relationships and positive approaches to sex education, including how to gain consent before sex. There was a need identified for school-based programmes to better consider the needs of Aboriginal young people, including those who identified as LGBTQI + . Aboriginal Medical Services were highly valued for providing culturally safe access to services, while sexual health clinics were valued for providing specialised confidential clinical services with low levels of judgement.


Subject(s)
Australian Aboriginal and Torres Strait Islander Peoples , Sex Education , Adolescent , Humans , Australia , Delivery of Health Care , Reproducibility of Results
11.
Soft Matter ; 18(44): 8476-8485, 2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36317698

ABSTRACT

E-skins consisting of soft pressure sensors are enabling technology for soft robots, bio-integrated devices, and deformable touch panels. A well-known bottleneck of capacitive pressure sensors (CPS) is the drastic decay in sensitivity with increasing pressure. To overcome this challenge, we have invented a hybrid-response pressure sensor (HRPS) that exhibits both the piezoresistive and piezocapacitive effects intrinsic to a highly porous nanocomposite (PNC) with carbon nanotube (CNT) dopants. The HRPS is constructed with two conductive electrodes sandwiching a laminated PNC and a stiff dielectric layer. We have simplified the hybrid response into a parallel resistor-capacitor circuit, whose output depends on the AC (alternating current) frequency used for the capacitance measurement. Herein, through theoretical analysis, we discover a dimensionless parameter that governs the frequency responses of the HRPS. The master curve is validated through experiments on the HRPS with various doping ratios, subject to different compressive strains, under diverse AC frequencies. In addition, the relative contribution of piezoresistive and piezocapacitive mechanisms are also found to vary with the three parameters. Based on this experimentally validated theory, we establish a very practical guideline for selecting the optimal AC frequency for the capacitance measurement of HRPSs.

12.
PLoS One ; 17(2): e0263612, 2022.
Article in English | MEDLINE | ID: mdl-35143563

ABSTRACT

Vaccines are one of the most cost-effective tools for improving human health and well-being. The impact of a vaccine on population health is partly determined by its coverage rate, the proportion of eligible individuals vaccinated. Coverage rate is a function of the vaccine presentation and the population in which that presentation is deployed. This population includes not only the individuals vaccinated, but also the logistics and healthcare systems responsible for vaccine delivery. Because vaccine coverage rates remain below targets in many settings, vaccine manufacturers and purchasers have a shared interest in better understanding the relationship between vaccine presentation, population characteristics, and coverage rate. While there have been some efforts to describe this relationship, existing research and tools are limited in their ability to quantify coverage rate changes across a broad set of antigens, vaccine presentations, and geographies. In this article, we present a method for estimating the impact of improved vaccine technologies on vaccination coverage rates. It is designed for use with low- and middle-income country vaccination programs. This method uses publicly available data and simple calculations based on probability theory to generate coverage rate values. We first present the conceptual framework and mathematical approach. Using a Microsoft Excel-based implementation, we then apply the method to a vaccine technology in early-stage development: micro-array patch for a measles-rubella vaccine (MR-MAP). Example outputs indicate that a complete switch from the current subcutaneous presentation to MR-MAP in the 73 countries ever eligible for Gavi support would increase overall vaccination coverage by 3.0-4.9 percentage points depending on the final characteristics of the MR-MAP. This change equates to an additional 2.6-4.2 million children vaccinated per year. Our method can be readily extended to other antigens and vaccine technologies to provide quick, low-cost estimates of coverage impact. As vaccine manufacturers and purchasers face increasingly complex decisions, such estimates could facilitate objective comparisons between options and help these decision makers obtain the most value for money.


Subject(s)
Data Interpretation, Statistical , Measles-Mumps-Rubella Vaccine/immunology , Vaccination Coverage , Vaccine Development , Biotechnology , Humans , Immunization Programs , Mathematics , Technology, Pharmaceutical/trends
13.
Eur J Med Chem ; 231: 114163, 2022 Mar 05.
Article in English | MEDLINE | ID: mdl-35131537

ABSTRACT

Intrinsically disordered proteins (IDPs) play important roles in disease pathologies; however, their lack of defined stable 3D structures make traditional drug design strategies typically less effective against these targets. Based on promising results of targeted covalent inhibitors (TCIs) on challenging targets, we have developed a covalent design strategy targeting IDPs. As a model system we chose tau, an endogenous IDP of the central nervous system that is associated with severe neurodegenerative diseases via its aggregation. First, we mapped the tractability of available cysteines in tau and prioritized suitable warheads. Next, we introduced the selected vinylsulfone warhead to the non-covalent scaffolds of potential tau aggregation inhibitors. The designed covalent tau binders were synthesized and tested in aggregation models, and inhibited tau aggregation effectively. Our results revealed the usefulness of the covalent design strategy against therapeutically relevant IDP targets and provided promising candidates for the treatment of tauopathies.


Subject(s)
Intrinsically Disordered Proteins , Neurodegenerative Diseases , Tauopathies , Cysteine , Drug Design , Humans , Intrinsically Disordered Proteins/chemistry , Neurodegenerative Diseases/metabolism , Tauopathies/drug therapy , tau Proteins/metabolism
14.
Methods Mol Biol ; 2263: 247-270, 2021.
Article in English | MEDLINE | ID: mdl-33877602

ABSTRACT

This chapter describes the use of NMR to screen a fragment library as part of a fragment-based lead discovery (FBLD) campaign. The emphasis is on the practicalities involved in fragment screening by NMR, with particular attention to the use of 1D ligand-observed 1H NMR experiments. An overview of the theoretical considerations underlying the choice of method and experimental configuration is given, along with a discussion of steps that can be taken in order to minimize the risk of experimental artifacts often associated with the identification of low-affinity interactions.


Subject(s)
Drug Discovery/methods , Proton Magnetic Resonance Spectroscopy/methods , Small Molecule Libraries/analysis , High-Throughput Screening Assays , Ligands , Structure-Activity Relationship
15.
J Med Educ Curric Dev ; 7: 2382120520973214, 2020.
Article in English | MEDLINE | ID: mdl-33283050

ABSTRACT

OBJECTIVES: To evaluate and analyze the efficacy of implementation of hemorrhage-control training into the formal medical school curriculum. We predict this training will increase the comfort and confidence levels of students with controlling major hemorrhage and they will find this a valuable skill set for medical and other healthcare professional students. METHODS: After IRB and institutional approval was obtained, hemorrhage-control education was incorporated into the surgery clerkship curriculum for 96 third-year medical students at the University of Arkansas for Medical Sciences using the national Stop The Bleed program. Using a prospective study design, participants completed pre- and post-training surveys to gauge prior experiences and comfort levels with controlling hemorrhage and confidence levels with the techniques taught. Course participation was mandatory; survey completion was optional. The investigators were blinded as to the individual student's survey responses. A knowledge quiz was completed following the training. RESULTS: Implementation of STB training resulted in a significant increase in comfort and confidence among students with all hemorrhage-control techniques. There was also a significant difference in students' perceptions of the importance of this training for physicians and other allied health professionals. CONCLUSION: Hemorrhage-control training can be effectively incorporated into the formal medical school curriculum via a single 2-hour Stop The Bleed course, increasing students' comfort level and confidence with controlling major traumatic bleeding. Students value this training and feel it is a beneficial addition to their education. We believe this should be a standard part of undergraduate medical education.

16.
Int J Mol Sci ; 21(15)2020 Jul 24.
Article in English | MEDLINE | ID: mdl-32722166

ABSTRACT

Over the past decade intrinsically disordered proteins (IDPs) have emerged as a biologically important class of proteins, many of which are of therapeutic relevance. Here, we investigated the interactions between a model IDP system, tau K18, and nine literature compounds that have been reported as having an effect on tau in order to identify a robust IDP-ligand system for the optimization of a range of biophysical methods. We used NMR, surface plasmon resonance (SPR) and microscale thermophoresis (MST) methods to investigate the binding of these compounds to tau K18; only one showed unambiguous interaction with tau K18. Several near neighbors of this compound were synthesized and their interactions with tau K18 characterized using additional NMR methods, including 1D ligand-observed NMR, diffusion-ordered spectroscopy (DOSY) and 19F NMR. This study demonstrates that it is possible to detect and characterize IDP-ligand interactions using biophysical methods. However, care must be taken to account for possible artefacts, particularly the impact of compound solubility and where the protein has to be immobilized.


Subject(s)
Intrinsically Disordered Proteins/chemistry , Molecular Docking Simulation , tau Proteins/chemistry , Humans , Ligands , Nuclear Magnetic Resonance, Biomolecular
17.
J Biomol NMR ; 74(1): 95-109, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31915980

ABSTRACT

NMR spectroscopy provides a powerful approach for the characterisation of chemical exchange and molecular interactions by analysis of series of experiments acquired over the course of a titration measurement. The appearance of NMR resonances undergoing chemical exchange depends on the frequency difference relative to the rate of exchange, and in the case of one-dimensional experiments chemical exchange regimes are well established and well known. However, two-dimensional experiments present additional complexity, as at least one additional frequency difference must be considered. Here we provide a systematic classification of chemical exchange regimes in two-dimensional NMR spectra. We highlight important differences between exchange in HSQC and HMQC experiments, that on a practical level result in more severe exchange broadening in HMQC spectra, but show that complementary alternatives to the HMQC are available in the form of HZQC and HDQC experiments. We present the longitudinal relaxation optimised SOFAST-H(Z/D)QC experiment for the simultaneous acquisition of sensitivity-enhanced HZQC and HDQC spectra, and the longitudinal and transverse relaxation optimised BEST-ZQ-TROSY for analysis of large molecular weight systems. We describe the application of these experiments to the characterisation of the interaction between the Hsp90 N-terminal domain and a small molecule ligand, and show that the independent analysis of HSQC, HMQC, HZQC and HDQC experiments provides improved confidence in the fitted dissociation constant and dissociation rate. Joint analysis of such data may provide improved sensitivity to detect and analyse more complex multi-state interaction mechanisms such as induced fit or conformational selection.


Subject(s)
Algorithms , Nuclear Magnetic Resonance, Biomolecular , Quantum Theory , HSP90 Heat-Shock Proteins/chemistry , HSP90 Heat-Shock Proteins/metabolism , Ligands , Protein Binding , Protein Domains
18.
RSC Med Chem ; 11(5): 591-596, 2020 May 01.
Article in English | MEDLINE | ID: mdl-33479661

ABSTRACT

Recently we have established an NMR molecular replacement method, which is capable of solving the structure of the interaction site of protein-ligand complexes in a fully automated manner. While the method was successfully applied for ligands with strong and weak binding affinities, including small molecules and peptides, its applicability on ligand fragments remains to be shown. Structures of fragment-protein complexes are more challenging for the method since fragments contain only few protons. Here we show a successful application of the NMR molecular replacement method in solving structures of complexes between three derivatives of a ligand fragment and the protein receptor PIN1. We anticipate that this approach will find a broad application in fragment-based lead discovery.

19.
ACS Omega ; 4(5): 8892-8906, 2019 May 31.
Article in English | MEDLINE | ID: mdl-31459977

ABSTRACT

We describe our work to establish structure- and fragment-based drug discovery to identify small molecules that inhibit the anti-apoptotic activity of the proteins Mcl-1 and Bcl-2. This identified hit series of compounds, some of which were subsequently optimized to clinical candidates in trials for treating various cancers. Many protein constructs were designed to identify protein with suitable properties for different biophysical assays and structural methods. Fragment screening using ligand-observed NMR experiments identified several series of compounds for each protein. The series were assessed for their potential for subsequent optimization using 1H and 15N heteronuclear single-quantum correlation NMR, surface plasmon resonance, and isothermal titration calorimetry measurements to characterize and validate binding. Crystal structures could not be determined for the early hits, so NMR methods were developed to provide models of compound binding to guide compound optimization. For Mcl-1, a benzodioxane/benzoxazine series was optimized to a K d of 40 µM before a thienopyrimidine hit series was identified which subsequently led to the lead series from which the clinical candidate S 64315 (MIK 665) was identified. For Bcl-2, the fragment-derived series were difficult to progress, and a compound derived from a published tetrahydroquinone compound was taken forward as the hit from which the clinical candidate (S 55746) was obtained. For both the proteins, the work to establish a portfolio of assays gave confidence for identification of compounds suitable for optimization.

20.
J Med Chem ; 62(15): 6913-6924, 2019 08 08.
Article in English | MEDLINE | ID: mdl-31339316

ABSTRACT

Myeloid cell leukemia 1 (Mcl-1), an antiapoptotic member of the Bcl-2 family of proteins, whose upregulation when observed in human cancers is associated with high tumor grade, poor survival, and resistance to chemotherapy, has emerged as an attractive target for cancer therapy. Here, we report the discovery of selective small molecule inhibitors of Mcl-1 that inhibit cellular activity. Fragment screening identified thienopyrimidine amino acids as promising but nonselective hits that were optimized using nuclear magnetic resonance and X-ray-derived structural information. The introduction of hindered rotation along a biaryl axis has conferred high selectivity to the compounds, and cellular activity was brought on scale by offsetting the negative charge of the anchoring carboxylate group. The obtained compounds described here exhibit nanomolar binding affinity and mechanism-based cellular efficacy, caspase induction, and growth inhibition. These early research efforts illustrate drug discovery optimization from thienopyrimidine hits to a lead compound, the chemical series leading to the identification of our more advanced compounds S63845 and S64315.


Subject(s)
Cell Survival/physiology , Drug Discovery/methods , Myeloid Cell Leukemia Sequence 1 Protein/antagonists & inhibitors , Myeloid Cell Leukemia Sequence 1 Protein/metabolism , Pyrimidines/chemistry , Pyrimidines/metabolism , Thiophenes/chemistry , Thiophenes/metabolism , Cell Survival/drug effects , HCT116 Cells , HeLa Cells , Humans , Protein Structure, Tertiary , Pyrimidines/pharmacology , Structure-Activity Relationship , Thiophenes/pharmacology
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