Patterns of physical activity of people with COPD during participation in a pulmonary rehabilitation program.

INTRODUCTION: Very few studies have examined patterns of physical activity (PA) during a pulmonary rehabilitation (PR) program in people with COPD. AIMS: To compare the patterns of PA in: 1) the week before commencing PR (pre-PR) with a week during PR (PR week); 2) PR days and non-PR days during a PR week; 3) pre-PR and the week following PR completion (post PR). METHODS: This was a multicenter, prospective cohort study. Participants attended twice weekly supervised PR for 8-12 weeks. Daily step count (primary outcome), time in light activities, time in moderate to vigorous PA (MVPA), total sedentary time and sit-to-stand (STS) transitions were measured using a thigh worn accelerometer for seven days, at each assessment time point: pre-PR, PR week and post PR. RESULTS: 29 participants, mean age (SD) 69years(7), FEV1 53%pred(16). The PR week compared to pre-PR, showed higher daily: step count (mean difference (95%CI)), 941steps(388-1494); and MVPA, 11mins(6-15), with no difference in: time in light activities, -1min(-6-5); total sedentary time, 7mins(-21-36); or STS transitions, 0(-5-6). PR days compared to non-PR days showed higher: step count, 2810steps(1706-3913); time in light activities 11mins(1-20); time in MVPA, 27mins(17-35) and STS transitions, 8(4-12), with no difference in total sedentary time: -33mins(-80-15). There were no differences in any PA measures post-PR compared to pre-PR (p<0.05). CONCLUSION: Daily step count and time spent in MVPA increased significantly during the PR week, solely due to increased PA on days participants attended PR.

Effect of a 4-Week Telerehabilitation Program for People with Post-COVID Syndrome on Physical Function and Symptoms: Protocol for a Randomized Controlled Trial.

OBJECTIVE: COVID-19 has led to significant morbidity and mortality globally. Post-COVID sequelae can persist beyond the acute and subacute phases of infection, often termed Post-COVID Syndrome (PCS). There is limited evidence on the appropriate rehabilitation for people with PCS. The aim of this study is to evaluate the effect on exercise capacity, symptoms, cognition, anxiety, depression, health-related quality of life (HRQoL), and fatigue, of a 4-week, twice-weekly supervised pulmonary telerehabilitation program compared to usual medical care for people with PCS with persistent respiratory symptoms. METHODS: The study will be a multi-site randomized controlled trial (RCT) with assessor blinding. Participants with confirmed previous COVID-19 infection and persistent respiratory symptoms who attend a post-COVID respiratory clinic will be randomized 1:1 to either an intervention group (IG) of 4 weeks, twice-weekly pulmonary telerehabilitation or a control group (CG) of usual medical care. Participants in the CG will be invited to cross-over into the IG after the week 4 assessment. Primary outcome: exercise capacity measured by the 1-minute sit-to-stand test. Secondary outcomes: 5 repetition sit-to-stand test; Montreal Cognitive Assessment; COVID-19 Yorkshire Rehabilitation Scale; COPD Assessment Test; 36-Item Short-Form Health Survey; Hospital Anxiety and Depression Scale; Fatigue Severity Scale; and the Kessler Psychological Distress Scale. Outcomes will be collected at baseline, after 4-weeks intervention or control period, after intervention in the cross-over group, and at 12-month follow-up. IMPACT STATEMENT: Research into effective rehabilitation programs is crucial given the substantial morbidity associated with PCS and the lack of long-term data for COVID-19 recovery. A short duration pulmonary telerehabilitation program, if effective compared to usual care, could inform practice guidelines and direct future clinical trials for the benefit of individuals with persistent respiratory symptoms post-COVID.

University students' willingness to receive a COVID-19 vaccine in the United States.

The disproportionate number of COVID-19 cases and deaths in the United States (US) requires understanding of health behaviors that contributed to low acceptance of public health guidelines. University students were at low risk for complications from COVID-19 infections but at high-risk for infecting others. It is important to understand which characteristics influenced willingness to receive the COVID-19 vaccine. The purpose of this cross-sectional study was to explore the social factors and identities that predicted university students' willingness to receive COVID-19 vaccines before one was available. This study used a stratified random sample from a Midwestern public university in 2020 (N = 614). Results suggest hesitancy toward childhood vaccinations, noncompliance with mask-wearing and large-group-avoidance guidelines, and conservative political ideology increased the odds of being unwilling to receive a COVID-19 vaccination. However, higher subjective social status and male gender increased the odds of being willing to be vaccinated.

Disposable platform for bacterial lysis and nucleic acid amplification based on a single USB-powered printed circuit board.

Recent advances in electronics and microfluidics have enabled several research groups to develop fully integrated, sample-to-result isothermal nucleic acid amplification test (NAAT) platforms for the point of care. However, high component counts and costs have limited translation of these platforms beyond the clinic to low-resource settings-including homes. Many NAATs include complex, multi-component heater electronics based on flex circuits or multiple printed circuit boards (PCBs) to support essential NAAT steps such as lysis, sample deactivation, and nucleic acid amplification. In contrast, current commercial assays for home use, such as those for pregnancy or ovulation that include electronics, typically have just one onboard PCB. This work describes a generalizable strategy to integrate all heaters and the electronics needed to control them onto a single low-cost, USB-powered PCB. We built a multiplexable disposable NAAT ("MD NAAT") platform that applies these principles, integrating small-area heaters that heat small regions to near-boiling (for pathogen lysis and deactivation) and large-area heaters (for amplification) on the same PCB. We show that both classes of heaters have high intra-board and inter-device reproducibility despite only heating a NAAT cartridge from below. We validated the small-area heaters by lysing methicillin-resistant Staphylococcus aureus (MRSA) cells and the large-area heaters by performing two types of isothermal NAATs (isothermal strand displacement amplification (iSDA) and loop-mediated isothermal amplification (LAMP)). These results demonstrate the merit of integrating NAAT heaters and control electronics onto a single printed circuit board and are a step toward translating NAATs to the home.

Shape-Morphing of an Artificial Protein Cage with Unusual Geometry Induced by a Single Amino Acid Change.

Artificial protein cages are constructed from multiple protein subunits. The interaction between the subunits, notably the angle formed between them, controls the geometry of the resulting cage. Here, using the artificial protein cage, "TRAP-cage", we show that a simple alteration in the position of a single amino acid responsible for Au(I)-mediated subunit-subunit interactions in the constituent ring-shaped building blocks results in a more acute dihedral angle between them. In turn, this causes a dramatic shift in the structure from a 24-ring cage with an octahedral symmetry to a 20-ring cage with a C2 symmetry. This symmetry change is accompanied by a decrease in the number of Au(I)-mediated bonds between cysteines and a concomitant change in biophysical properties of the cage.

"You say you're inclusive, but can you show us?" The importance of cultural competence when working with sexual minorities in a mental health setting.

OBJECTIVES: Sexual minorities experience higher rates of psychological distress than heterosexual people, likely due to minority stress. While rates of help-seeking by sexual minorities are high, sexual minorities report greater dissatisfaction with mental health service providers. This dissatisfaction may result from poor cultural competence practices. Our study sought to determine the importance of service provider cultural competence practices to a community sample of sexual minority people. METHODS: Participants (n = 274) were sexual minority Australians recruited from affirming Facebook groups, organizations, and research-based organizations. To measure the importance of cultural competence practices, participants completed a modified online version of the Gay Affirming Practices Scale (GAP) and responded to open-ended questions. RESULTS: Between 80% and 99% of participants endorsed each item on the GAP, indicating the importance of service providers demonstrating an array of culturally affirming practices. No significant associations were found between overall GAP score and age or sexual orientation, though further analyses revealed individual items on the GAP showed associations with age. A structured tabular thematic analysis, of open-ended participant responses, found positive attitudes, knowledge, and affirming practices were the three most important characteristics for service providers seeking to demonstrate culturally competent practices, mirroring the tripartite model (attitudes, knowledge, and skills) of cultural competence. CONCLUSION: Recommendations for service providers to demonstrate cultural competence include: utilizing affirming practices such as inclusive language, increasing knowledge about sexual minorities, and utilizing education resources such as cultural competence workshops, lived experience stories, and seeking mentorship from service providers with expertise in working with sexual minorities.

Automated liquid handling robot for rapid lateral flow assay development.

The lateral flow assay (LFA) is one of the most popular technologies on the point-of-care diagnostics market due to its low cost and ease of use, with applications ranging from pregnancy to environmental toxins to infectious disease. While the use of these tests is relatively straightforward, significant development time and effort are required to create tests that are both sensitive and specific. Workflows to guide the LFA development process exist but moving from target selection to an LFA that is ready for field testing can be labor intensive, resource heavy, and time consuming. To reduce the cost and the duration of the LFA development process, we introduce a novel development platform centered on the flexibility, speed, and throughput of an automated robotic liquid handling system. The system comprises LFA-specific hardware and software that enable large optimization experiments with discrete and continuous variables such as antibody pair selection or reagent concentration. Initial validation of the platform was demonstrated during development of a malaria LFA but was readily expanded to encompass development of SARS-CoV-2 and Mycobacterium tuberculosis LFAs. The validity of the platform, where optimization experiments are run directly on LFAs rather than in solution, was based on a direct comparison between the robotic system and a more traditional ELISA-like method. By minimizing hands-on time, maximizing experiment size, and enabling improved reproducibility, the robotic system improved the quality and quantity of LFA assay development efforts.

A systematic review to determine how service provider practises impact effective service provision to lesbian, gay and bisexual consumers in a mental health setting.

Lesbian, gay and bisexual (LGB) consumers utilize mental health services at a similar rate to their heterosexual counterparts yet report greater dissatisfaction with service quality. This dissatisfaction may be explained by service provider's microaggressions, stemming from a lack of cultural competence in working with LGB consumers. This systematic review examines how the practises of mental health service providers impacted effective service provision to LGB people in a clinical practice. Five health databases (Scopus, MEDLINE, PsycINFO, Web of Science and CINAHL) were examined to determine relevant studies for this review. Twenty four qualitative and quantitative studies between 2000 and 2020 examining data related to how service provider practises impacted effective service provision to LGB people were included in the final review. A narrative synthesis, thematic summary approach was employed to account for the multi-method nature of the data. Themes developed in our analysis are organized under the three components of cultural competence, service provider attitudes, knowledge and skills. Provider attitudes ranged from positive to negative towards LGB people and heterosexism were present in several services. Poor service provider knowledge about the issues impacting LGB consumers leads to a weakened therapeutic alliance and service providers often lacked a comprehensive understanding of the issues impacting LGB people. Service providers were seen as more skilful if they were LGB, created a safe space and had completed cultural competence training. Trends within the characteristics (explorative nature, mixed service provider samples, potential for bias) of the 24 studies included in the review are discussed. Based on the results, recommendations are included to ensure services demonstrate cultural competence in working with LGB consumers.

Changes in Exercise Capacity and Health-Related Quality of Life at Four and Eight Weeks of a Pulmonary Rehabilitation Program in People with COPD.

Pulmonary Rehabilitation (PR) is a key intervention in the management of people with chronic obstructive pulmonary disease (COPD), though few studies have assessed where changes in outcomes occur during a PR program. The aim of this study was to determine the changes in exercise capacity and health-related quality of life at four and eight weeks during a twice-weekly supervised PR program in people with COPD. Fifty participants with COPD were recruited and attended PR twice-weekly for eight weeks. The outcome measures were the endurance shuttle walk test (ESWT), six-minute walk distance (6MWD), St George's Respiratory Questionnaire (SGRQ), COPD Assessment Test (CAT) and the Hospital Anxiety and Depression Scale (HADS) which were measured at baseline, four and eight weeks. Compared to baseline, at week four there were significant improvements in ESWT (mean difference [95%CI] 197 [89 to 305] seconds), 6MWD (22 [8 to 36] metres), SGRQ symptom score (-6 [-12 to -1] points) and SGRQ total score (-4 [-7 to -1] points). Between week four and eight there were further significant improvements in ESWT (94 [8 to 181] seconds) only. By week eight, ESWT, 6MWD, SGRQ symptoms and total score, and CAT had all improved significantly compared to baseline measures. This study demonstrated that participants with moderate to very severe COPD who participated in a twice weekly, eight-week PR program (16 sessions) had significant improvement in ESWT, 6MWD, SGRQ, and CAT score with the greatest improvements occurring in the first four weeks of the program.Supplemental data for this article is available online at https://doi.org/10.1080/15412555.2021.2013793 .

Antibody Screening Results for Anti-Nucleocapsid Antibodies Toward the Development of a Lateral Flow Assay to Detect SARS-CoV-2 Nucleocapsid Protein.

The global COVID-19 pandemic has created an urgent demand for large numbers of inexpensive, accurate, rapid, point-of-care diagnostic tests. Analyte-based assays are suitably rapid and inexpensive and can be rapidly mass-produced, but for sufficiently accurate performance, they require highly optimized antibodies and assay conditions. We used an automated liquid handling system, customized to handle arrays of lateral flow (immuno)assays (LFAs) in a high-throughput screen, to identify anti-nucleocapsid antibodies that will perform optimally in an LFA. We tested 1021 anti-nucleocapsid antibody pairs as LFA capture and detection reagents with the goal of highlighting pairs that have the greatest affinity for the nucleocapsid protein of SARS-CoV-2 within the LFA format. In contrast to traditional antibody screening methods (e.g., ELISA, bio-layer interferometry), the method described here integrates real-time reaction kinetics with transport in, and immobilization directly onto, nitrocellulose. We have identified several candidate antibody pairs that are suitable for further development of an LFA for SARS-CoV-2.

Identification and Mechanistic Characterization of a Peptide Inhibitor of Glycogen Synthase Kinase (GSK3ß) Derived from the Disrupted in Schizophrenia 1 (DISC1) Protein.

Glycogen synthase kinase 3-beta (GSK3ß) is a critical regulator of several cellular pathways involved in neurodevelopment and neuroplasticity and as such is a potential focus for the discovery of new neurotherapeutics toward the treatment of neuropsychiatric and neurodegenerative diseases. The majority of efforts to develop inhibitors of GSK3ß have been focused on developing small molecule inhibitors that compete with adenosine triphosphate (ATP) through direct interaction with the ATP binding site. This strategy has presented selectivity challenges due to the evolutionary conservation of this domain within the kinome. The disrupted in schizophrenia 1 (DISC1) protein has previously been shown to bind and inhibit GSK3ß activity. Here, we report the characterization of a 44-mer peptide derived from human DISC1 (hDISCtide) that is sufficient to both bind and inhibit GSK3ß in a noncompetitive mode distinct from classical ATP competitive inhibitors. Based on multiple independent biochemical and biophysical assays, we propose that hDISCtide interacts at two distinct regions of GSK3ß: an inhibitory region that partially overlaps with the binding site of FRATide, a well-known GSK3ß binding peptide, and a specific binding region that is unique to hDISCtide. Taken together, our findings present a novel avenue for developing a peptide-based selective inhibitor of GSK3ß.

Effect of a pulmonary rehabilitation programme of 8 weeks compared to 12 weeks duration on exercise capacity in people with chronic obstructive pulmonary disease (PuRe Duration): protocol for a randomised controlled trial.

INTRODUCTION: Pulmonary rehabilitation (PR) is a key component in the management of chronic obstructive pulmonary disease (COPD). There is no strong evidence on the optimal duration of PR programmes. The aim of this study is to determine whether an 8-week PR programme is equivalent to a 12-week PR programme in people with COPD. METHODS AND ANALYSIS: This study will be a prospective, multisite, randomised controlled, equivalence trial with assessors blinded to group allocation and intention-to-treat analysis. 72 participants with COPD will be recruited and randomised to either a supervised, twice weekly for 8 weeks or a 12-week PR programme of exercise training and education. PRIMARY OUTCOME: endurance shuttle walk test. SECONDARY OUTCOMES: will include St George's Respiratory Questionnaire, 6-min walk distance, COPD assessment test, Hospital Anxiety and Depression Scale, physical activity monitoring and hospital admissions at 6 months and 12 months. Repeated measures analysis of variance will be used to analyse differences between the groups for all outcomes. ETHICS AND DISSEMINATION: Ethics approval was gained from all participating sites. Results of the trial will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ACTRN12616001586404.

Two-Fluorophore Mobile Phone Imaging of Biplexed Real-Time NAATs Overcomes Optical Artifacts in Highly Scattering Porous Media.

Nucleic acid amplification tests (NAATs) are common in laboratory and clinical settings because of their low time to result and exquisite sensitivity and specificity. Laboratory NAATs include onboard positive controls to reduce false negatives and specialized hardware to enable real-time fluorescence detection. Recent efforts to translate NAATs into at-home tests sacrifice one or more of the benefits of laboratory NAATs, such as sensitivity, internal amplification controls (IACs), or time to result. In this manuscript, we describe a mobile-phone-based strategy for real-time imaging of biplexed NAATs in paper. The strategy consisted of: (1) using mobile phones with multipass excitation and emission filters on the flash and camera to image the signal from distinct fluorophore-labeled probe types in a biplexed NAAT in a glass fiber membrane; and (2) analyzing the differential fluorescence signal between the red and green color channels of phone images to overcome a strong evaporation-induced optical artifact in heated glass fiber pads due to changes in the refractive index. We demonstrated that differential fluorescence imaging enabled low limits of detection (316 copies of methicillin-resistant Staphylococcus aureus DNA) in our lab's "MD NAAT" platform, even in biplexed isothermal strand displacement amplification reactions containing 100k copies of coamplifying IAC DNA templates. These results suggest that two-fluorophore mobile phone imaging may enable translating the benefits of extant laboratory-based, real-time NAATs to the point of care.

Discovery of suppressors of CRMP2 phosphorylation reveals compounds that mimic the behavioral effects of lithium on amphetamine-induced hyperlocomotion.

The effective treatment of bipolar disorder (BD) represents a significant unmet medical need. Although lithium remains a mainstay of treatment for BD, limited knowledge regarding how it modulates affective behavior has proven an obstacle to discovering more effective mood stabilizers with fewer adverse side effects. One potential mechanism of action of lithium is through inhibition of the serine/threonine protein kinase GSK3ß, however, relevant substrates whose change in phosphorylation may mediate downstream changes in neuroplasticity remain poorly understood. Here, we used human induced pluripotent stem cell (hiPSC)-derived neuronal cells and stable isotope labeling by amino acids in cell culture (SILAC) along with quantitative mass spectrometry to identify global changes in the phosphoproteome upon inhibition of GSK3α/ß with the highly selective, ATP-competitive inhibitor CHIR-99021. Comparison of phosphorylation changes to those induced by therapeutically relevant doses of lithium treatment led to the identification of collapsin response mediator protein 2 (CRMP2) as being highly sensitive to both treatments as well as an extended panel of structurally distinct GSK3α/ß inhibitors. On this basis, a high-content image-based assay in hiPSC-derived neurons was developed to screen diverse compounds, including FDA-approved drugs, for their ability to mimic lithium's suppression of CRMP2 phosphorylation without directly inhibiting GSK3ß kinase activity. Systemic administration of a subset of these CRMP2-phosphorylation suppressors were found to mimic lithium's attenuation of amphetamine-induced hyperlocomotion in mice. Taken together, these studies not only provide insights into the neural substrates regulated by lithium, but also provide novel human neuronal assays for supporting the development of mechanism-based therapeutics for BD and related neuropsychiatric disorders.

Sensitivity enhancement in lateral flow assays: a systems perspective.

Lateral flow assays (LFAs) are rapid, inexpensive, easy-to-manufacture and -use tests widely employed in medical and environmental applications, particularly in low resource settings. Historically, LFAs have been stigmatized as having limited sensitivity. However, as their global usage expands, extensive research has demonstrated that it is possible to substantially improve LFA sensitivity without sacrificing their advantages. In this critical review, we have compiled state-of-the-art approaches to LFA sensitivity enhancement. Moreover, we have organized and evaluated these approaches from a system-level perspective, as we have observed that the advantages and disadvantages of each approach have arisen from the integrated and tightly interconnected chemical, physical, and optical properties of LFAs.

Drug discovery for psychiatric disorders using high-content single-cell screening of signaling network responses ex vivo.

There is a paucity of efficacious new compounds to treat neuropsychiatric disorders. We present a novel approach to neuropsychiatric drug discovery based on high-content characterization of druggable signaling network responses at the single-cell level in patient-derived lymphocytes ex vivo. Primary T lymphocytes showed functional responses encompassing neuropsychiatric medications and central nervous system ligands at established (e.g., GSK-3ß) and emerging (e.g., CrkL) drug targets. Clinical application of the platform to schizophrenia patients over the course of antipsychotic treatment revealed therapeutic targets within the phospholipase Cγ1-calcium signaling pathway. Compound library screening against the target phenotype identified subsets of L-type calcium channel blockers and corticosteroids as novel therapeutically relevant drug classes with corresponding activity in neuronal cells. The screening results were validated by predicting in vivo efficacy in an independent schizophrenia cohort. The approach has the potential to discern new drug targets and accelerate drug discovery and personalized medicine for neuropsychiatric conditions.

The oral health status, behaviours and knowledge of patients with cardiovascular disease in Sydney Australia: a cross-sectional survey.

BACKGROUND: Periodontal disease is a risk factor for atherosclerotic cardiovascular disease and it is recommended internationally that patients with cardiovascular disease should engage in preventative oral health practices and attend regular dental care visits. This study aimed to explore the oral health status, behaviours and knowledge of patients with cardiovascular disease. METHODS: A cross-sectional questionnaire containing 31 items was administered to patients with cardiovascular disease from cardiac rehabilitation and outpatient clinics in Sydney Australia in 2016-2017. RESULTS: Of the 318 patients surveyed, 81.1% reported having at least one oral health problem. Over a third (41.2%) of participants had not seen a dentist in the preceding 12 months and 10.7% had received any oral healthcare information in the cardiac setting. Those with valvular conditions were more likely to have received information compared to those with other cardiovascular conditions (40.6% versus 7.4%, p < 0.001). Only half of the participants had adequate oral health knowledge. CONCLUSIONS: Despite a high incidence of reported oral health problems, many patients lacked knowledge about oral health, were not receiving oral health information from cardiac care providers and had difficulty accessing dental services. Further research is needed to develop oral health strategies in this area.

Foster Care Alumni Achievement in Higher Education: the Role of Trauma.

Foster care alumni lag behind the general population in post-secondary academic achievement. This cross-sectional study uses a random sample of forty-six foster care alumni from a Midwestern public university to explore the relationship between exposure to trauma and post-secondary academic achievement (14.5% response rate; age range 17-24). While no significant relationship was found between trauma exposure and GPA or failing classes, participants who experienced increased exposure to trauma were more likely to have withdrawn from a class because it was too difficult or the semester was too overwhelming. More research is needed to further understand these findings.

Oral health and cardiovascular care: Perceptions of people with cardiovascular disease.

MAIN OBJECTIVE: The aim of this study was to explore the perception of patients with cardiovascular disease towards oral health and the potential for cardiac care clinicians to promote oral health. METHOD: A needs assessment was undertaken with twelve patients with cardiovascular disease attending cardiac rehabilitation between 2015 and 2016, in three metropolitan hospitals in Sydney, Australia. These patients participated in face-to-face semi-structured interviews. Data was analysed using thematic analysis. RESULTS: Results suggested that while oral health was considered relevant there was high prevalence of poor oral health among participants, especially those from socioeconomic disadvantaged background. Awareness regarding the importance of oral health care its impact on cardiovascular outcomes was poor among participants. Oral health issues were rarely discussed in the cardiac setting. Main barriers deterring participants from seeking oral health care included lack of awareness, high cost of dental care and difficulties in accessing the public dental service. Findings also revealed that participants were interested in receiving further information about oral health and suggested various mediums for information delivery. The concept of cardiac care clinicians, especially nurses providing education, assessment and referrals to ongoing dental care was well received by participants who felt the post-acute period was the most appropriate time to receive oral health care advice. The issues of oral health training for non-dental clinicians and how to address existing barriers were highlighted by participants. RELEVANCE TO CLINICAL PRACTICE: The lack of oral health education being provided to patients with cardiovascular disease offers an opportunity to improve care and potentially, outcomes. In view of the evidence linking poor oral health with cardiovascular disease, cardiac care clinicians, especially nurses, should be appropriately trained to promote oral health in their practice. Affordable and accessible dental care services for people with cardiovascular disease should be considered and offered by health services in Australia.

Diversity-Oriented Synthesis as a Strategy for Fragment Evolution against GSK3ß.

Traditional fragment-based drug discovery (FBDD) relies heavily on structural analysis of the hits bound to their targets. Herein, we present a complementary approach based on diversity-oriented synthesis (DOS). A DOS-based fragment collection was able to produce initial hit compounds against the target GSK3ß, allow the systematic synthesis of related fragment analogues to explore fragment-level structure-activity relationship, and finally lead to the synthesis of a more potent compound.