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1.
J Pediatr Gastroenterol Nutr ; 79(5): 934-942, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38937992

RESUMO

There are two main complementary feeding (CF) approaches: traditional spoon-feeding (TSF) and baby-led weaning (BLW). Many parents and healthcare professionals have concerns about the risk of choking associated with BLW. Since asphyxia is one of infants' main causes of death, this study aims to understand the influence of the CF approach adopted by caregivers on infants' risk of choking. A systematic review was performed. The search was conducted through PubMed, Scopus, and Web of Science databases. We included randomized controlled trials or observational studies published between January 2010 and November 2023, with a clear definition of the intervention and directly assessing the risk of choking. After the selection procedure, 7 of the 165 studies initially identified were included. No study reported statistically significant differences in the risk of choking between babies following BLW, baby-led introduction to solids (BLISS), and TSF. In five studies, although not statistically significant, infants in the TSF group had more choking episodes than those in the BLW or BLISS groups. The risk of choking does not seem to be associated with the CF approach. Instead, it may be related to the familiarity of the baby with each texture and the parent's understanding of the information about how to minimize the risk of choking. Recall bias may be present in all included studies. Advice on how to modify foods to make them safer needs to be clearer and reinforced to all parents.


Assuntos
Obstrução das Vias Respiratórias , Fenômenos Fisiológicos da Nutrição do Lactente , Desmame , Humanos , Lactente , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/prevenção & controle , Alimentos Infantis , Fatores de Risco
2.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474312

RESUMO

The role of the epidermal growth factor receptor (EGFR) in tumor progression and survival is often underplayed. Its expression and/or dysregulation is associated with disease advancement and poor patient outcome as well as drug resistance in breast cancer. EGFR is often overexpressed in breast cancer and particularly triple-negative breast cancer (TNBC), which currently lacks molecular targets. We examined the synergistic potential of an EGFR inhibitor (EGFRi) in combination with doxorubicin (Dox) in estrogen-positive (ER+) MCF-7 and MDA-MB-231 TNBC cell lines. The exposure of MDA-MB-231 and MCF-7 to EGFRi produced an IC50s of 6.03 µM and 3.96 µM, respectively. Dox induced MDA-MB-231 (IC50 9.67 µM) and MCF-7 (IC50 1.4 µM) cytotoxicity. Combinations of EGFRi-Dox significantly reduced the IC50 in MCF-7 (0.46 µM) and MBA-MB 231 (0.01 µM). Synergistic drug interactions in both cell lines were confirmed using the Bliss independence model. Pro-apoptotic Caspase-3/7 activation occurred in MCF-7 at 0.1-10 µM of EGFRi and Dox single treatments, whilst 1 µM Dox yielded a more potent effect on MDA-MB-231. EGFRi and Dox individually and in combination downregulated the EGFR gene expression in MCF-7 and MDA-MB-231 (p < 0.001). This study demonstrates EGFRi's potential for eliciting synergistic interactions with Dox, causing enhanced growth inhibition, apoptosis induction, and downregulation of EGFR in both cell lines.


Assuntos
Doxorrubicina , Receptores ErbB , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Doxorrubicina/farmacologia , Receptores ErbB/antagonistas & inibidores , Células MCF-7 , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Sinergismo Farmacológico
3.
Stat Pap (Berl) ; : 1-34, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36643817

RESUMO

The use of historical, i.e., already existing, estimates in current studies is common in a wide variety of application areas. Nevertheless, despite their routine use, the uncertainty associated with historical estimates is rarely properly accounted for in the analysis. In this communication, we review common practices and then provide a mathematical formulation and a principled frequentist methodology for addressing the problem of drawing inferences in the presence of historical estimates. Three distinct variants are investigated in detail; the corresponding limiting distributions are found and compared. The design of future studies, given historical data, is also explored and relations with a variety of other well-studied statistical problems discussed.

4.
J Relig Health ; 62(3): 2163-2180, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36155872

RESUMO

Genuine happiness can be described as an unlimited, everlasting inner joy and peace undisturbed by external circumstances. The current study proposes a Genuine Happiness Scale (GHS) with four items. The sample consisted of 678 US young adults, with 432 completing the online surveys twice, approximately six weeks apart. Exploratory and confirmatory factor analysis provided evidence for a unidimensional factor structure of the GHS. Hierarchical regression analysis revealed that, after controlling for genuine happiness at baseline, caring for bliss, mindfulness, and compassion predicted genuine happiness approximately six weeks later. In addition, genuine happiness predicted later well-being after controlling for well-being at baseline.


Assuntos
Empatia , Felicidade , Adulto Jovem , Humanos , Inquéritos e Questionários
5.
Virol J ; 19(1): 143, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071449

RESUMO

The recently published AMP trial (HVTN 703/HPTN 081 and HVTN704/HPTN 085) results have validated broad neutralising antibodies (bNAbs) as potential anti-HIV-1 agents. However, single bNAb preparations are unlikely to cope with the onslaught of existing and de novo resistance mutations, thus necessitating the use of bNAb combinations to achieve clinically relevant results. Specifically engineered antibodies incorporating two bNAbs into a single antibody structure have been developed. These bispecific antibodies (bibNAbs) retain the benefits of bNAb combinations, whilst several conformations exhibit improved neutralisation potency over the parental bNAbs. Here we report on the engineering of a bibNAb comprising of an HIV-1 spike targeting bNAb N6 and a host CD4 targeting antibody ibalizumab (iMab). Antibodies were expressed in HEK293T cells and purified by protein-A affinity chromatography followed by size exclusion chromatography to achieve homogenous, monomeric, bibNAb preparations. Antibody purity was confirmed by SDS-PAGE whilst epitope specificity and binding were confirmed by ELISA. Finally, antibody breadth and potency data were generated by HIV-1 neutralisation assay (n = 21, inclusive of the global panel). iMab-N6 exhibited better neutralisation breadth (100% coverage) in comparison to its parental bNAbs iMab (90%) and N6 (95%). This is encouraging as exceptional neutralisation breadth is necessary for HIV-1 treatment or prevention. Unfortunately, iMab-N6 did not exhibit any enhancement in potency over the most potent parental antibody, iMab (p = 0.1674, median IC50 of 0.0475 µg/ml, and 0.0665 µg/ml respectively) or the parental combination, iMab + N6 (p = 0.1964, median IC50: combination 0.0457 µg/ml). This result may point to a lack of dual engagement of the bibNAb Fab moieties necessary for potency enhancement. Against the previously reported bibNAbs; iMab-CAP256, 10E08-iMab, and PG9-iMab; iMab-N6 was the lowest performing bibNAb. The re-engineering of iMab-N6 to enhance its potency, while retaining breadth, is a worthwhile endeavour due to its clinical potential.


Assuntos
Anticorpos Biespecíficos , Infecções por HIV , HIV-1 , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Células HEK293 , Anticorpos Anti-HIV , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Testes de Neutralização , Pais
6.
BMC Bioinformatics ; 20(1): 83, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30777010

RESUMO

BACKGROUND: Drug combinations have the potential to improve efficacy while limiting toxicity. To robustly identify synergistic combinations, high-throughput screens using full dose-response surface are desirable but require an impractical number of data points. Screening of a sparse number of doses per drug allows to screen large numbers of drug pairs, but complicates statistical assessment of synergy. Furthermore, since the number of pairwise combinations grows with the square of the number of drugs, exploration of large screens necessitates advanced visualization tools. RESULTS: We describe a statistical and visualization framework for the analysis of large-scale drug combination screens. We developed an approach suitable for datasets with large number of drugs pairs even if small number of data points are available per drug pair. We demonstrate our approach using a systematic screen of all possible pairs among 108 cancer drugs applied to melanoma cell lines. In this dataset only two dose-response data points per drug pair and two data points per single drug test were available. We used a Bliss-based linear model, effectively borrowing data from the drug pairs to obtain robust estimations of the singlet viabilities, consequently yielding better estimates of drug synergy. Our method improves data consistency across dosing thus likely reducing the number of false positives. The approach allows to compute p values accounting for standard errors of the modeled singlets and combination viabilities. We further develop a synergy specificity score that distinguishes specific synergies from those arising with promiscuous drugs. Finally, we developed a summarized interactive visualization in a web application, providing efficient access to any of the 439,000 data points in the combination matrix ( http://www.cmtlab.org:3000/combo_app.html ). The code of the analysis and the web application is available at https://github.com/arnaudmgh/synergy-screen . CONCLUSIONS: We show that statistical modeling of single drug response from drug combination data can help determine significance of synergy and antagonism in drug combination screens with few data point per drug pair. We provide a web application for the rapid exploration of large combinatorial drug screen. All codes are available to the community, as a resource for further analysis of published data and for analysis of other drug screens.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Modelos Estatísticos , Linhagem Celular Tumoral , Gráficos por Computador , Conjuntos de Dados como Assunto , Sinergismo Farmacológico , Humanos , Modelos Lineares
7.
Pharm Stat ; 18(6): 688-699, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31140720

RESUMO

Linear models are generally reliable methods for analyzing tumor growth in vivo, with drug effectiveness being represented by the steepness of the regression slope. With immunotherapy, however, not all tumor growth follows a linear pattern, even after log transformation. Tumor kinetics models are mechanistic models that describe tumor proliferation and tumor killing macroscopically, through a set of differential equations. In drug combination studies, although an additional drug-drug interaction term can be added to such models, however, the drug interactions suggested by tumor kinetics models cannot be translated directly into synergistic effects. We have developed a novel statistical approach that simultaneously models tumor growth in control, monotherapy, and combination therapy groups. This approach makes it possible to test for synergistic effects directly and to compare such effects among different studies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Imunoterapia/métodos , Modelos Teóricos , Neoplasias/tratamento farmacológico , Interações Medicamentosas , Sinergismo Farmacológico , Humanos , Cinética , Modelos Lineares , Neoplasias/patologia , Resultado do Tratamento
8.
Theor Biol Med Model ; 14(1): 15, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28768512

RESUMO

BACKGROUND: The classification of effects caused by mixtures of agents as synergistic, antagonistic or additive depends critically on the reference model of 'null interaction'. Two main approaches are currently in use, the Additive Dose (ADM) or concentration addition (CA) and the Multiplicative Survival (MSM) or independent action (IA) models. We compare several response surface models to a newly developed Hill response surface, obtained by solving a logistic partial differential equation (PDE). Assuming that a mixture of chemicals with individual Hill-type dose-response curves can be described by an n-dimensional logistic function, Hill's differential equation for pure agents is replaced by a PDE for mixtures whose solution provides Hill surfaces as 'null-interaction' models and relies neither on Bliss independence or Loewe additivity nor uses Chou's unified general theory. METHODS: An n-dimensional logistic PDE decribing the Hill-type response of n-component mixtures is solved. Appropriate boundary conditions ensure the correct asymptotic behaviour. Mathematica 11 (Wolfram, Mathematica Version 11.0, 2016) is used for the mathematics and graphics presented in this article. RESULTS: The Hill response surface ansatz can be applied to mixtures of compounds with arbitrary Hill parameters. Restrictions which are required when deriving analytical expressions for response surfaces from other principles, are unnecessary. Many approaches based on Loewe additivity turn out be special cases of the Hill approach whose increased flexibility permits a better description of 'null-effect' responses. Missing sham-compliance of Bliss IA, known as Colby's model in agrochemistry, leads to incompatibility with the Hill surface ansatz. Examples of binary and ternary mixtures illustrate the differences between the approaches. For Hill-slopes close to one and doses below the half-maximum effect doses MSM (Colby, Bliss, Finney, Abbott) predicts synergistic effects where the Hill model indicates 'null-interaction'. These differences increase considerably with increasing steepness of the individual dose-response curves. CONCLUSION: The Hill response surface ansatz contains the Loewe additivity concept as a special case and is incompatible with Bliss independent action. Hence, when synergistic effects are claimed, those dose combinations deserve special attention where the differences between independent action approaches and Hill estimations are large.


Assuntos
Sinergismo Farmacológico , Modelos Biológicos , Dioxinas , Piretrinas
9.
Clin Infect Dis ; 63(suppl 3): S88-S94, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27742639

RESUMO

BACKGROUND: No treatment regimens have been specifically designed for children, in whom tuberculosis is predominantly intracellular. Given their activity as monotherapy and their ability to penetrate many diseased anatomic sites that characterize disseminated tuberculosis, linezolid and moxifloxacin could be combined to form a regimen for this need. METHODS: We examined microbial kill of intracellular Mycobacterium tuberculosis (Mtb) by the combination of linezolid and moxifloxacin multiple exposures in a 7-by-7 mathematical matrix. We then used the hollow fiber system (HFS) model of intracellular tuberculosis to identify optimal dose schedules and exposures of moxifloxacin and linezolid in combination. We mimicked pediatric half-lives and concentrations achieved by each drug. We sampled the peripheral compartment on days 0, 7, 14, 21, and 28 for Mtb quantification, and compared the slope of microbial kill of Mtb by these regimens to the standard regimen of isoniazid, rifampin, and pyrazinamide, based on exponential decline regression. RESULTS: The full exposure-response surface identified linezolid-moxifloxacin zones of synergy, antagonism, and additivity. A regimen based on each of these zones was then used in the HFS model, with observed half-lives of 4.08 ± 0.66 for linezolid and 3.80 ± 1.34 hours for moxifloxacin. The kill rate constant was 0.060 ± 0.012 per day with the moxifloxacin-linezolid regimen in the additivity zone vs 0.083 ± 0.011 per day with standard therapy, translating to a bacterial burden half-life of 11.52 days vs 8.53 days, respectively. CONCLUSIONS: We identified doses and dose schedules of a linezolid and moxifloxacin backbone regimen that could be highly efficacious in disseminated tuberculosis in children.


Assuntos
Antituberculosos/uso terapêutico , Fluoroquinolonas/uso terapêutico , Linezolida/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Tuberculose/microbiologia , Fatores Etários , Antituberculosos/farmacocinética , Carga Bacteriana , Linhagem Celular , Criança , Simulação por Computador , Antagonismo de Drogas , Sinergismo Farmacológico , Quimioterapia Combinada , Fluoroquinolonas/farmacocinética , Humanos , Linezolida/farmacocinética , Testes de Sensibilidade Microbiana/métodos , Modelos Teóricos , Moxifloxacina
10.
Lupus ; 25(4): 346-54, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26385220

RESUMO

INTRODUCTION: Patients with systemic lupus erythematosus (SLE) with B-lymphocyte stimulator (BLyS) levels ≥ 2 ng/mL are at increased risk of flare. A regression analysis was undertaken to identify routine clinical measures that correlate with BLyS ≥ 2 ng/mL. Efficacy and safety of belimumab 10 mg/kg were examined in patients with BLyS ≥ 2 ng/mL and < 2 ng/mL. METHODS: Data from BLISS-52 and -76 (N = 1684) were pooled post hoc. A univariate logistic regression was employed to identify factors predictive of baseline BLyS ≥ 2 ng/mL. Factors significant at the 0.05 level then entered a stepwise logistic regression as covariates. Efficacy endpoints included SLE responder index (SRI), ≥ 4-point reduction in Safety of Estrogens in Lupus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) and risk of severe flare over 52 weeks. Adverse events (AEs) were analyzed for each treatment arm and BLyS subgroup. RESULTS: Baseline predictors of BLyS ≥ 2 ng/mL included positive anti-Smith (≥ 15 U/mL), low complement (C) 3 (< 900 mg/L), anti-double-stranded DNA (anti-dsDNA) 80-200 and ≥ 200 IU/mL, immunosuppressant usage, proteinuria, elevated C-reactive protein (CRP), and low total lymphocyte count for all patients. Belimumab 10 mg/kg led to significantly greater SRI responses over 52 weeks versus placebo in both BLyS subgroups, though treatment differences were numerically greater at Week 52 in the BLyS ≥ 2 ng/mL group (24.1%, p < 0.0001) compared with BLyS < 2 ng/mL (8.2%, p = 0.0158). Results were similar for ≥ 4-point reduction in SELENA-SLEDAI. Risk of severe flare over 52 weeks was significantly reduced with belimumab 10 mg/kg versus placebo in the BLyS ≥ 2 ng/mL group (p = 0.0002). AEs were similar across treatment arms and BLyS subgroups. CONCLUSIONS: Positive anti-Smith, low C3, anti-dsDNA ≥ 80 IU/mL, immunosuppressant usage, proteinuria, elevated CRP, and low total lymphocyte count were predictors of BLyS ≥ 2 ng/mL. Monitoring these factors could identify patients with BLyS ≥ 2 ng/mL who are at risk of flare.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fator Ativador de Células B/sangue , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Fator Ativador de Células B/imunologia , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Progressão da Doença , Feminino , Humanos , Imunossupressores/efeitos adversos , Modelos Logísticos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
11.
J Pharmacokinet Pharmacodyn ; 43(5): 461-79, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27638639

RESUMO

Drugs interact with their targets in different ways. A diversity of modeling approaches exists to describe the combination effects of two drugs. We investigate several combination effect terms (CET) regarding their underlying mechanism based on drug-receptor binding kinetics, empirical and statistical summation principles and indirect response models. A list with properties is provided and the interrelationship of the CETs is analyzed. A method is presented to calculate the optimal drug concentration pair to produce the half-maximal combination effect. This work provides a comprehensive overview of typically applied CETs and should shed light into the question as to which CET is appropriate for application in pharmacokinetic/pharmacodynamic models to describe a specific drug-drug interaction mechanism.


Assuntos
Interações Medicamentosas , Modelos Biológicos , Farmacocinética , Simulação por Computador , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Humanos , Cinética , Dinâmica não Linear , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/metabolismo , Ligação Proteica , Receptores de Droga/metabolismo
12.
Biometrics ; 70(2): 259-65, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24499157

RESUMO

The year 2012 marks the 50th anniversary of the death of Sir Ronald A. Fisher, one of the two Fathers of Statistics and a Founder of the International Biometric Society (the "Society"). To celebrate the extraordinary genius of Fisher and the far-sighted vision of Fisher and Chester Bliss in organizing and promoting the formation of the Society, this article looks at the origins and growth of the Society, some of the key players and events, and especially the roles played by Fisher himself as the First President. A fresh look at Fisher, the man rather than the scientific genius is also presented.


Assuntos
Biometria/história , Sociedades Científicas/história , História do Século XX , Humanos , Internacionalidade , Sociedades Científicas/organização & administração
13.
Am J Lifestyle Med ; 18(1): 75-81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39184273

RESUMO

Cardiovascular disease (CVD) and mental health disorders contribute to significant healthcare expenses. Lifestyle approaches that empower and enable patients to participate in their recovery are needed with the increasing complexity of cardiac patients. Traditional Tamil medical practice of Siddha self-inquiry meditation targets holistic health through intuitive lifestyle transformation. We describe 4 complex cardiac patients who explored Siddha based Hunger Gratitude Experience (HUGE) mindful eating and reported elevated levels of optimism and deeper experience of life as outlined by the 5000-year-old secular Siddha medical tradition. We cannot exclude the role of suggestion and placebo effect in descriptive series. However, the simultaneous improvement in physical health and emotional wellbeing along with demonstrated resilience against unforeseen adversities suggests this is Uvagai, the true essence of Siddha higher consciousness. Uvagai is extreme happiness and may be accessible universally with little formal training and targets positive psychology to improve wellbeing. While flow and bliss states are transient transcendental experiences, Uvagai may be more profound and therapeutic in CVD despite age and comorbidities. Seeking Uvagai can potentially overcome health disparities, including rural, minority, and underprivileged populations for better health. HUGE allows CVD patients to safely engage in Uvagai, experience higher consciousness and intuitively sustain lifestyle transformation.

14.
In Vivo ; 38(4): 1740-1749, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38936885

RESUMO

BACKGROUND/AIM: To date, therapeutic options for T-cell acute lymphoblastic leukemia (T-ALL) remain very limited. This study evaluated the efficacy of monotherapies and combination therapies including a selective BCL-2 inhibitor for T-ALL cell lines, namely Jurkat, CCRF-CEM, and Loucy. MATERIALS AND METHODS: Loucy is an early T-precursor ALL (ETP-ALL) cell line characterized by an immature phenotype, whereas Jurkat and CCRF-CEM are late T-cell progenitor ALL (LTP-ALL) cell lines. Monotherapy was conducted with venetoclax, cytarabine, bendamustine, or azacytidine, whereas combination therapy was performed with venetoclax plus cytarabine, venetoclax plus bendamustine, or venetoclax plus azacytidine. Cell viability assay was conducted after 48 h using Trypan blue and the 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS). Statistical analysis for evaluating synergistic interactions between anticancer drugs was performed by using the SynergyFinder Plus and drc R package. RESULTS: Adding venetoclax to cytarabine, bendamustine, or azacitidine achieved an additive effect, with Loewe synergic scores ranging from -10 to 10 in Jurkat and CCRF-CEM. Conversely, the combination of venetoclax and cytarabine displayed an additive effect (Loewe synergic score: 8.45 and 5.82 with MTS and Trypan blue assays, respectively), whereas venetoclax plus bendamustine or azacitidine exhibited a synergistic effect (Loewe synergic score >10 with MTS assay) in Loucy. Remarkably, the Bliss/Loewe score revealed that the combination of venetoclax and bendamustine was the most synergistic, yielding a score of 13.832±0.55. CONCLUSION: The combination of venetoclax and bendamustine demonstrated the greatest synergistic effect in suppressing ETP-ALL cell proliferation. Further studies are warranted to determine the mechanisms for the synergism between venetoclax and bendamustine in high-risk T-ALL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Cloridrato de Bendamustina , Compostos Bicíclicos Heterocíclicos com Pontes , Sinergismo Farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Sulfonamidas , Humanos , Cloridrato de Bendamustina/administração & dosagem , Cloridrato de Bendamustina/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Jurkat , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
15.
Evol Appl ; 17(8): e13764, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39100751

RESUMO

In combination therapy, bacteria are challenged with two or more antibiotics simultaneously. Ideally, separate mutations are required to adapt to each of them, which is a priori expected to hinder the evolution of full resistance. Yet, the success of this strategy ultimately depends on how well the combination controls the growth of bacteria with and without resistance mutations. To design a combination treatment, we need to choose drugs and their doses and decide how many drugs get mixed. Which combinations are good? To answer this question, we set up a stochastic pharmacodynamic model and determine the probability to successfully eradicate a bacterial population. We consider bacteriostatic and two types of bactericidal drugs-those that kill independent of replication and those that kill during replication. To establish results for a null model, we consider non-interacting drugs and implement the two most common models for drug independence-Loewe additivity and Bliss independence. Our results show that combination therapy is almost always better in limiting the evolution of resistance than administering just one drug, even though we keep the total drug dose constant for a 'fair' comparison. Yet, exceptions exist for drugs with steep dose-response curves. Combining a bacteriostatic and a bactericidal drug which can kill non-replicating cells is particularly beneficial. Our results suggest that a 50:50 drug ratio-even if not always optimal-is usually a good and safe choice. Applying three or four drugs is beneficial for treatment of strains with large mutation rates but adding more drugs otherwise only provides a marginal benefit or even a disadvantage. By systematically addressing key elements of treatment design, our study provides a basis for future models which take further factors into account. It also highlights conceptual challenges with translating the traditional concepts of drug independence to the single-cell level.

16.
J Biomol Struct Dyn ; : 1-16, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38179981

RESUMO

DNA topoisomerase 1 (Topo 1) is a pivotal player in various DNA processes, including replication, repair, and transcription. It serves as a target for anticancer drugs like camptothecin and its derivatives (Topotecan and SN-38/Irinotecan). However, the emergence of drug resistance and the associated adverse effects, such as alopecia, anemia, dyspnea, fever, chills, and painful or difficult urination, pose significant challenges in Topo 1-targeted therapy, necessitating urgent attention. Human DNA Ligase 1 (hLig I), recognized primarily for its role in DNA replication and repair of DNA breaks, intriguingly exhibits a DNA relaxation activity akin to Topo 1. This raised the hypothesis that hLig I might compensate for Topo 1 inhibition, contributing to resistance against Topo 1 inhibitors. To explore this hypothesis, we assessed the efficacy of hLig I inhibition alone and in combination with Topo 1 in cancer cells. As anticipated, the overexpression of hLig I was observed after Topo 1 inhibition in colorectal cancer cells, affirming our hypothesis. Previously identified as an inhibitor of hLig I's DNA relaxation activity, compound 27 (C 27), when combined with Topotecan, demonstrated a synergistic antiproliferative effect on colorectal cancer cells. Notably, cells with downregulated hLig I (via siRNA, inhibitors, or genetic manipulation) exhibited significantly heightened sensitivity to Topotecan. This observation strongly supports the concept that hLig I contribute to resistance against clinically relevant Topo 1 inhibitors in colorectal cancers. In conclusion, our findings offer evidence for the synergistic impact of combining hLig I inhibitors with Topotecan in the treatment of colorectal cancers, providing a promising strategy to overcome resistance to Topo 1 inhibitors.Communicated by Ramaswamy H. Sarma.

17.
Cell Rep Med ; 5(8): 101687, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39168097

RESUMO

Combining drugs can enhance their clinical efficacy, but the number of possible combinations and inter-tumor heterogeneity make identifying effective combinations challenging, while existing approaches often overlook clinically relevant activity. We screen one of the largest cell line panels (N = 757) with 51 clinically relevant combinations and identify responses at the level of individual cell lines and tissue populations. We establish three response classes to model cellular effects beyond monotherapy: synergy, Bliss additivity, and independent drug action (IDA). Synergy is rare (11% of responses) and frequently efficacious (>50% viability reduction), whereas Bliss and IDA are more frequent but less frequently efficacious. We introduce "efficacious combination benefit" (ECB) to describe high-efficacy responses classified as either synergy, Bliss, or IDA. We identify ECB biomarkers in vitro and show that ECB predicts response in patient-derived xenografts better than synergy alone. Our work here provides a valuable resource and framework for preclinical evaluation and the development of combination treatments.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Sinergismo Farmacológico , Neoplasias , Humanos , Linhagem Celular Tumoral , Animais , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo
18.
Stat Med ; 32(29): 5145-55, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-23904140

RESUMO

A method for detecting deviations from the Loewe additive drug combination reference model for in vitro drug combination experimentation is described. It is often difficult to fit a response surface model to drug combination data, especially in situations where the experimental design contains a sparse set of combinations. The literature does contain good response surface modeling approaches, but they tend to be complex and can be difficult to execute. It is especially difficult to check model quality when fitting to more than two combined agents. A simple method based on sound statistical principles is proposed that examines the mean response deviation of each combination from the predicted response under Loewe additivity. The method can readily handle any number of combined agents, does not require sophisticated modeling, and can even be programmed into Microsoft Excel without the use of macros. Several potential extensions to the method are discussed in detail. Computer-generated simulations demonstrate the statistical capabilities of the approach, and a real-data example is given to illustrate the method.


Assuntos
Interpretação Estatística de Dados , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada/métodos , Modelos Estatísticos , Antivirais/uso terapêutico , Quimioterapia Combinada/normas , Herpes Simples/tratamento farmacológico , Humanos
19.
J Emerg Med ; 45(3): 361-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23827164

RESUMO

BACKGROUND: Bath salts commonly contain multiple synthetic drugs, and their toxic effects are largely the same as those seen in patients who have taken large doses of amphetamines. Bath salts can be ingested, smoked, or administered intravenously. Their use is on the rise and is responsible for a large number of emergency department visits. CASE REPORT: Our case series involved five patients (six hospital courses) who presented after ingesting bath salts. The presentations involved signs and symptoms of intense sympathetic response. All patients had a history of drug abuse, and most had psychiatric disorders as well. Treatments included benzodiazepines, mechanical ventilation, and intravenous hydration. CONCLUSION: Bath salts are available for approximately $20 (USD) in packets at truck stops and on the Internet, usually marketed with the disclaimer, "not for human consumption." Their presentation mimics other sympathetic drugs and causes a significant amount of delirium, hallucinogenic-delusional symptoms, extreme agitation, combativeness, and rhabdomyolysis, often leading to hospitalizations and intensive care unit (ICU) stays. Management is largely supportive and includes aggressive intravenous hydration, dampening of the excessive sympathetic outflow with benzodiazepines, and close monitoring in the ICU setting. The U.S. Drug Enforcement Administration (DEA) recently invoked its emergency scheduling authority to control these synthetic stimulants. The DEA plans to make possessing and selling these chemicals, or products that contain them, illegal in the United States.


Assuntos
Estimulantes do Sistema Nervoso Central/intoxicação , Drogas Desenhadas/intoxicação , Drogas Ilícitas/intoxicação , Transtornos Mentais/complicações , Adulto , Agressão , Acatisia Induzida por Medicamentos/etiologia , Benzodiazepinas/uso terapêutico , Alucinações/induzido quimicamente , Humanos , Masculino , Intoxicação/terapia
20.
Eur J Ophthalmol ; : 11206721231207116, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37844600

RESUMO

PURPOSE: To analyze the efficacy of liposomal ozonated oil (Ozonest®) treatment, in patients with blepharitis or blepharoconjunctivitis, in improving the signs and symptoms of the pathology. METHODS: Exploratory, open-label, prospective, single-arm, pre-post comparative pilot study in usual clinical practice, in 20 patients with blepharitis/blepharoconjunctivitis, receiving treatment with liposomal ozonated oil, one drop in each eye, 4 times a day, for 28 days. Main purpose was to assess whether there was a clinically improvement in the blepharitis specific BLISS questionnaire score. Changes in the 12-item OSDI, in eyelid signs of blepharitis assessed by the physicians were also evaluated among other tests, and there was also a subjective evaluation of the treatment by patients. RESULTS: The BLISS score significantly improved from 16.4 before treatment to 11.8 after treatment (p < 0.05). The OSDI score was also significantly improved from 27.5 before treatment to 20.5 after treatment (p < 0.05). All tests conducted before and after treatment showed significant improvement (p < 0.05), except for NIBUT. The treatment received a score of 7 out of 10 by the patients. There were no adverse events in any patient. CONCLUSION: Liposomal ozonated oil treatment showed good efficacy in improving the signs and symptoms of blepharitis/blepharoconjunctivitis, satisfaction of patients, and good safety and tolerability.

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