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1.
Mol Pharm ; 21(1): 53-61, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38029291

ABSTRACT

Epithelial-mesenchymal transition (EMT) is a reversible and dynamic biological process in which epithelial cells acquire mesenchymal characteristics including enhanced stemness and migratory ability. EMT can facilitate cancer metastasis and is a known driver of cellular resistance to common chemotherapeutic drugs, such as docetaxel. Current chemotherapeutic practices such as docetaxel treatment can promote EMT and increase the chance of tumor recurrence and resistance, calling for new approaches in cancer treatment. Here we show that prolonged docetaxel treatment at a sub-IC50 concentration inhibits EMT in immortalized human mammary epithelial (HMLE) cells. Using immunofluorescence, flow cytometry, and bulk transcriptomic sequencing to assess EMT progression, we analyzed a range of cellular markers of EMT in docetaxel-treated cells and observed an upregulation of epithelial markers and downregulation of mesenchymal markers in the presence of docetaxel. This finding suggests that docetaxel may have clinical applications not only as a cytotoxic drug but also as an inhibitor of EMT-driven metastasis and multidrug resistance depending on the concentration of its use.


Subject(s)
Antineoplastic Agents , Epithelial-Mesenchymal Transition , Humans , Docetaxel/pharmacology , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Epithelial Cells
2.
Econ J (London) ; 134(657): 436-456, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38077853

ABSTRACT

We measure the adoption of management practices in over 220 private for-profit and non-profit health facilities in 64 districts across Tanzania and link these data to process quality-of-care metrics, assessed using undercover standardised patients and clinical observations. We find that better managed health facilities are more likely to provide correct treatment in accordance with national treatment guidelines, adhere to a checklist of essential questions and examinations, and comply with infection prevention and control practices. Moving from the 10th to the 90th percentile in the management practice score is associated with a 48% increase in correct treatment. We then leverage a large-scale field experiment of an internationally recognised management support intervention in which health facilities are assessed against comprehensive standards, given an individually tailored quality improvement plan and supported through training and mentoring visits. We find zero to small effects on management scores, suggesting that improving management practices in this setting may be challenging.

3.
Chem Sci ; 14(28): 7681-7687, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37476710

ABSTRACT

DNA G-quadruplexes (G4s) have been identified as important biological targets for transcriptional, translational, and epigenetic regulation. The stabilisation of G4s with small molecule ligands has emerged as a technique to regulate gene expression and as a potential therapeutic approach for human diseases. Here, we demonstrate that ligand stabilisation of G4s causes altered chromatin accessibility dependent on the targeting specificity of the molecule. In particular, stabilisation of a target G4 using the highly specific GTC365 ligand resulted in differential accessibility of 61 genomic regions, while the broad-targeting G4 ligand, GQC-05, stabilised many G4s and induced a global shift towards increased accessibility of gene promoter regions. Interestingly, while we observed distinct effects of each ligand on RNA expression levels and the induction of DNA double-stranded breaks, both ligands modified DNA damage response pathways. Our work represents the dual possibility of G4-stabilising ligands for specific or global chromatin modulation via unique targeting characteristics.

4.
J Am Chem Soc ; 144(31): 14112-14120, 2022 08 10.
Article in English | MEDLINE | ID: mdl-35901278

ABSTRACT

Non-viral delivery is an important strategy for selective and efficient gene therapy, immunization, and RNA interference, which overcomes problems of genotoxicity and inherent immunogenicity associated with viral vectors. Liposomes and polymers are compelling candidates as carriers for intracellular, non-viral delivery, but maximal efficiencies of around 1% have been reported for the most advanced non-viral carriers. Here, we develop a library of dendronized bottlebrush polymers with controlled defects, displaying a level of precision surpassed only by biological molecules like DNA, RNA, and proteins. We test concurrent and competitive delivery of DNA and show for the first time that, while intracellular communication is thought to be an exclusively biomolecular phenomenon, such communication between synthetic macromolecular complexes can also take place. Our findings challenge the assumption that delivery agents behave as bystanders that enable transfection by passive intracellular release of genetic cargo and improve upon coarse strategies in intracellular carrier design lacking control over polymer sequence, architecture, and composition, leading to a hit-or-miss outcome. Understanding the communication that takes place between macromolecules will help improve the design of non-viral delivery agents and facilitate translation of genome engineering, vaccines, and nucleic acid-based therapies.


Subject(s)
Liposomes , Polymers , Cell Communication , DNA/metabolism , Gene Transfer Techniques , Liposomes/metabolism , Transfection
5.
Biochimie ; 198: 33-47, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35259471

ABSTRACT

DNA is naturally dynamic and can self-assemble into alternative secondary structures including the intercalated motif (i-motif), a four-stranded structure formed in cytosine-rich DNA sequences. Until recently, i-motifs were thought to be unstable in physiological cellular environments. Studies demonstrating their existence in the human genome and role in gene regulation are now shining light on their biological relevance. Herein, we review the effects of epigenetic modifications on i-motif structure and stability, and biological factors that affect i-motif formation within cells. Furthermore, we highlight recent progress in targeting i-motifs with structure-specific ligands for biotechnology and therapeutic purposes.


Subject(s)
Cytosine , DNA , Base Sequence , Cytosine/chemistry , DNA/chemistry , Epigenesis, Genetic , Humans , Nucleotide Motifs
6.
Lancet Glob Health ; 9(9): e1262-e1272, 2021 09.
Article in English | MEDLINE | ID: mdl-34363766

ABSTRACT

BACKGROUND: Quality of care is consistently shown to be inadequate in health-care settings in many low-income and middle-income countries, including in private facilities, which are rapidly growing in number but often do not have effective quality stewardship mechanisms. The SafeCare programme aims to address this gap in quality of care, using a standards-based approach adapted to low-resource settings, involving assessments, mentoring, training, and access to loans, to improve clinical quality and facility business performance. We assessed the effect of the SafeCare programme on quality of patient care in faith-based and private for-profit facilities in Tanzania. METHODS: In this cluster-randomised controlled trial, health facilities were eligible if they were dispensaries, health centres, or hospitals in the faith-based or private for-profit sectors in Tanzania. We randomly assigned facilities (1:1) using computer-generated stratified randomisation to receive the full SafeCare package (intervention) or an assessment only (control). Implementing staff and participants were masked to outcome measurement and the primary outcomes were measured by fieldworkers who had no knowledge of the study group allocation. The primary outcomes were health worker compliance with infection prevention and control (IPC) practices as measured by observation of provider-patient interactions, and correct case management of undercover standardised patients at endline (after a minimum of 18 months). Analyses were by modified intention to treat. The trial is registered with ISRCTN, ISRCTN93644888. FINDINGS: Between March 7 and Nov 30, 2016, we enrolled and randomly assigned 237 health facilities to the intervention (n=118) or control (n=119). Nine facilities (seven intervention facilities and two control facilities) closed during the trial and were not included in the analysis. We observed 29 608 IPC indications in 5425 provider-patient interactions between Feb 7 and April 5, 2018. Health facilities received visits from 909 standardised patients between May 3 and June 12, 2018. Intervention facilities had a 4·4 percentage point (95% CI 0·9-7·7; p=0.015) higher mean SafeCare standards assessment score at endline than control facilities. However, there was no evidence of a difference in clinical quality between intervention and control groups at endline. Compliance with IPC practices was observed in 8181 (56·9%) of 14 366 indications in intervention facilities and 8336 (54·7%) of 15 242 indications in control facilities (absolute difference 2·2 percentage points, 95% CI -0·2 to -4·7; p=0·071). Correct management occurred in 120 (27·0%) of 444 standardised patients in the intervention group and in 136 (29·2%) of 465 in the control group (absolute difference -2·8 percentage points, 95% CI -8·6 to -3·1; p=0·36). INTERPRETATION: SafeCare did not improve clinical quality as assessed by compliance with IPC practices and correct case management. The absence of effect on clinical quality could reflect a combination of insufficient intervention intensity, insufficient links between structural quality and care processes, scarcity of resources for quality improvement, and inadequate financial and regulatory incentives for improvement. FUNDING: UK Health Systems Research Initiative (Medical Research Council, Economic and Social Research Council, UK Department for International Development, Global Challenges Research Fund, and Wellcome Trust).


Subject(s)
Certification , Health Facilities/standards , Infection Control/standards , Quality Improvement/organization & administration , Quality of Health Care/statistics & numerical data , Faith-Based Organizations , Guideline Adherence/statistics & numerical data , Humans , Practice Guidelines as Topic , Private Sector , Program Evaluation , Tanzania
7.
Health Policy Plan ; 36(5): 695-706, 2021 Jun 03.
Article in English | MEDLINE | ID: mdl-33851694

ABSTRACT

Overprovision-healthcare whose harm exceeds its benefit-is of increasing concern in low- and middle-income countries, where the growth of the private-for-profit sector may amplify incentives for providing unnecessary care, and achieving universal health coverage will require efficient resource use. Measurement of overprovision has conceptual and practical challenges. We present a framework to conceptualize and measure overprovision, comparing for-profit and not-for-profit private outpatient facilities across 18 of mainland Tanzania's 22 regions. We developed a novel conceptualization of three harms of overprovision: economic (waste of resources), public health (unnecessary use of antimicrobial agents risking development of resistant organisms) and clinical (high risk of harm to individual patients). Standardized patients (SPs) visited 227 health facilities (99 for-profit and 128 not-for-profit) between May 3 and June 12, 2018, completing 909 visits and presenting 4 cases: asthma, non-malarial febrile illness, tuberculosis and upper respiratory tract infection. Tests and treatments prescribed were categorized as necessary or unnecessary, and unnecessary care was classified by type of harm(s). Fifty-three percent of 1995 drugs prescribed and 43% of 891 tests ordered were unnecessary. At the patient-visit level, 81% of SPs received unnecessary care, 67% received care harmful to public health (prescription of unnecessary antibiotics or antimalarials) and 6% received clinically harmful care. Thirteen percent of SPs were prescribed an antibiotic defined by WHO as 'Watch' (high priority for antimicrobial stewardship). Although overprovision was common in all sectors and geographical regions, clinically harmful care was more likely in for-profit than faith-based facilities and less common in urban than rural areas. Overprovision was widespread in both for-profit and not-for-profit facilities, suggesting considerable waste in the private sector, not solely driven by profit. Unnecessary antibiotic or antimalarial prescriptions are of concern for the development of antimicrobial resistance. Option for policymakers to address overprovision includes the use of strategic purchasing arrangements, provider training and patient education.


Subject(s)
Health Facilities , Outpatients , Cross-Sectional Studies , Delivery of Health Care , Humans , Tanzania
8.
J Am Chem Soc ; 142(49): 20600-20604, 2020 12 09.
Article in English | MEDLINE | ID: mdl-33253551

ABSTRACT

Guanine- and cytosine-rich nucleic acid sequences have the potential to form secondary structures such as G-quadruplexes and i-motifs, respectively. We show that stabilization of G-quadruplexes using small molecules destabilizes the i-motifs, and vice versa, indicating these gene regulatory controllers are interdependent in human cells. This has important implications as these structures are predominately considered as isolated structural targets for therapy, but their interdependency highlights the interplay of both structures as an important gene regulatory switch.


Subject(s)
G-Quadruplexes , Base Sequence , Cell Cycle Checkpoints/drug effects , Cell Nucleus/chemistry , Cell Nucleus/metabolism , Chromatin/metabolism , Ellipticines/pharmacology , G-Quadruplexes/drug effects , Genetic Loci , Humans , Ligands , MCF-7 Cells
9.
Lancet Glob Health ; 8(6): e780-e789, 2020 06.
Article in English | MEDLINE | ID: mdl-32389195

ABSTRACT

BACKGROUND: As coronavirus disease 2019 (COVID-19) spreads, weak health systems must not become a vehicle for transmission through poor infection prevention and control practices. We assessed the compliance of health workers with infection prevention and control practices relevant to COVID-19 in outpatient settings in Tanzania, before the pandemic. METHODS: This study was based on a secondary analysis of cross-sectional data collected as part of a randomised controlled trial in private for-profit dispensaries and health centres and in faith-based dispensaries, health centres, and hospitals, in 18 regions. We observed provider-patient interactions in outpatient consultation rooms, laboratories, and dressing rooms, and categorised infection prevention and control practices into four domains: hand hygiene, glove use, disinfection of reusable equipment, and waste management. We calculated compliance as the proportion of indications (infection risks) in which a health worker performed a correct action, and examined associations between compliance and health worker and facility characteristics using multilevel mixed-effects logistic regression models. FINDINGS: Between Feb 7 and April 5, 2018, we visited 228 health facilities, and observed at least one infection prevention and control indication in 220 facilities (118 [54%] dispensaries, 66 [30%] health centres, and 36 [16%] hospitals). 18 710 indications were observed across 734 health workers (49 [7%] medical doctors, 214 [29%] assistant medical officers or clinical officers, 106 [14%] nurses or midwives, 126 [17%] clinical assistants, and 238 [32%] laboratory technicians or assistants). Compliance was 6·9% for hand hygiene (n=8655 indications), 74·8% for glove use (n=4915), 4·8% for disinfection of reusable equipment (n=841), and 43·3% for waste management (n=4299). Facility location was not associated with compliance in any of the infection prevention and control domains. Facility level and ownership were also not significantly associated with compliance, except for waste management. For hand hygiene, nurses and midwives (odds ratio 5·80 [95% CI 3·91-8·61]) and nursing and medical assistants (2·65 [1·67-4·20]) significantly outperformed the reference category of assistant medical officers or clinical officers. For glove use, nurses and midwives (10·06 [6·68-15·13]) and nursing and medical assistants (5·93 [4·05-8·71]) also significantly outperformed the reference category. Laboratory technicians performed significantly better in glove use (11·95 [8·98-15·89]), but significantly worse in hand hygiene (0·27 [0·17-0·43]) and waste management (0·25 [0·14-0·44] than the reference category. Health worker age was negatively associated with correct glove use and female health workers were more likely to comply with hand hygiene. INTERPRETATION: Health worker infection prevention and control compliance, particularly for hand hygiene and disinfection, was inadequate in these outpatient settings. Improvements in provision of supplies and health worker behaviours are urgently needed in the face of the current pandemic. FUNDING: UK Medical Research Council, Economic and Social Research Council, Department for International Development, Global Challenges Research Fund, Wellcome Trust.


Subject(s)
Ambulatory Care Facilities , Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Guideline Adherence/statistics & numerical data , Infection Control/standards , Pandemics/prevention & control , Pneumonia, Viral/epidemiology , Pneumonia, Viral/prevention & control , Practice Guidelines as Topic , COVID-19 , Cross-Sectional Studies , Humans , Tanzania/epidemiology
10.
Health Policy Plan ; 34(8): 625-634, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31424494

ABSTRACT

Standardized patients (SPs), i.e. mystery shoppers for healthcare providers, are increasingly used as a tool to measure quality of clinical care, particularly in low- and middle-income countries where medical record abstraction is unlikely to be feasible. The SP method allows care to be observed without the provider's knowledge, removing concerns about the Hawthorne effect, and means that providers can be directly compared against each other. However, their undercover nature means that there are methodological and ethical challenges beyond those found in normal fieldwork. We draw on a systematic review and our own experience of implementing such studies to discuss six key steps in designing and executing SP studies in healthcare facilities, which are more complex than those in retail settings. Researchers must carefully choose the symptoms or conditions the SPs will present in order to minimize potential harm to fieldworkers, reduce the risk of detection and ensure that there is a meaningful measure of clinical care. They must carefully define the types of outcomes to be documented, develop the study scripts and questionnaires, and adopt an appropriate sampling strategy. Particular attention is required to ethical considerations and to assessing detection by providers. Such studies require thorough planning, piloting and training, and a dedicated and engaged field team. With sufficient effort, SP studies can provide uniquely rich data, giving insights into how care is provided which is of great value to both researchers and policymakers.


Subject(s)
Patient Simulation , Quality Assurance, Health Care/methods , Developing Countries , Female , Health Services Research/methods , Humans , Male , Quality Assurance, Health Care/ethics
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