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1.
Sci Rep ; 14(1): 6505, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499701

RESUMO

Ewing's sarcoma (ES) is the second most common bone tumor in children and adolescents and is highly malignant. Although the new chemotherapy has significantly improved the survival rate for ES from about 10 to 75%, the survival rate for metastatic tumors remains around 30%. This treatment is often associated with various side effects that contribute to the suffering of the patients. Cold physical plasma (CPP), whether used alone or in combination with current chemotherapy, is considered a promising adjunctive tool in cancer treatment. This study aims to investigate the synergistic effects of CPP in combination with cytostatic chemotherapeutic agents that are not part of current ES therapy. Two different ES cell lines, RD-ES and A673, were treated with the determined IC20 concentrations of the chemotherapeutic agents cisplatin and methotrexate (MTX) in combination with CPP. The effects on population doubling, cell viability, and apoptotic processes within these cell lines were assessed. This combination therapy has led to a reduction of population doubling and cell viability, as well as an increase in apoptotic activity in cells compared to CPP monotherapy. The results of this study provide evidence that combining CPP with non-common chemotherapy drugs such as MTX and CIS in the treatment of ES enhances the anticancer effects of these drugs. These findings open up new possibilities for the effective use of these drugs against ES.


Assuntos
Neoplasias Ósseas , Sarcoma de Ewing , Criança , Adolescente , Humanos , Sarcoma de Ewing/patologia , Neoplasias Ósseas/patologia , Terapia Combinada , Apoptose , Cisplatino/farmacologia , Cisplatino/uso terapêutico
2.
Int J Mol Sci ; 24(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37240019

RESUMO

Although Ewing's sarcoma (ES) is a rare, but very aggressive tumor disease affecting the musculoskeletal system, especially in children, it is very aggressive and difficult to treat. Although medical advances and the establishment of chemotherapy represent a turning point in the treatment of ES, resistance to chemotherapy, and its side effects, continue to be problems. New treatment methods such as the application of cold physical plasma (CPP) are considered potential supporting tools since CPP is an exogenous source of reactive oxygen and nitrogen species, which have similar mechanisms of action in the tumor cells as chemotherapy. This study aims to investigate the synergistic effects of CPP and commonly used cytostatic chemotherapeutics on ES cells. The chemotherapy drugs doxorubicin and vincristine, the most commonly used in the treatment of ES, were applied to two different ES cell lines (RD-ES and A673) and their IC20 and IC50 were determined. In addition, individual chemotherapeutics in combination with CPP were applied to the ES cells and the effects on cell growth, cell viability, and apoptosis processes were examined. A single CPP treatment resulted in the dose-dependent growth inhibition of ES cells. The combination of different cytostatics and CPP led to significant growth inhibition, a reduction in cell viability, and higher rates of apoptosis compared to cells not additionally exposed to CPP. The combination of CPP treatment and the application of cytostatic drugs to ES cells showed promising results, significantly enhancing the cytotoxic effects of chemotherapeutic agents. These preclinical in vitro data indicate that the use of CPP can enhance the efficacy of common cytostatic chemotherapeutics, and thus support the translation of CPP as an anti-tumor therapy in clinical routine.


Assuntos
Antineoplásicos , Neoplasias Ósseas , Citostáticos , Sarcoma de Ewing , Criança , Humanos , Sarcoma de Ewing/patologia , Citostáticos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Vincristina/farmacologia , Vincristina/uso terapêutico , Doxorrubicina/uso terapêutico , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral
3.
Am J Public Health ; 112(S5): S532-S536, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35767790

RESUMO

The Colorado Initiative to Reduce Unintended Pregnancy, including its largest subproject, the Colorado Family Planning Initiative, had a significant impact on contraceptive access during and after the project period. This coordinated and multilevel initiative improved reproductive health outcomes by driving change in public health systems, advancing statewide policies, building capacity through training and technical assistance, and increasing public awareness and education. Lessons learned from the implementation and outcomes of the Colorado Initiative to Reduce Unintended Pregnancy continue to inform contraceptive access efforts. (Am J Public Health. 2022;112(S5):S532-S536. https://doi.org/10.2105/AJPH.2022.306891).


Assuntos
Anticoncepção , Gravidez não Planejada , Colorado , Serviços de Planejamento Familiar , Feminino , Acesso aos Serviços de Saúde , Humanos , Gravidez , Saúde Reprodutiva
4.
Int J Mol Sci ; 23(9)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35563491

RESUMO

OCT1 and OCT2 are polyspecific membrane transporters that are involved in hepatic and renal drug clearance in humans and mice. In this study, we cloned dog OCT1 and OCT2 and compared their function to the human and mouse orthologs. We used liver and kidney RNA to clone dog OCT1 and OCT2. The cloned and the publicly available RNA-Seq sequences differed from the annotated exon-intron structure of OCT1 in the dog genome CanFam3.1. An additional exon between exons 2 and 3 was identified and confirmed by sequencing in six additional dog breeds. Next, dog OCT1 and OCT2 were stably overexpressed in HEK293 cells and the transport kinetics of five drugs were analyzed. We observed strong differences in the transport kinetics between dog and human orthologs. Dog OCT1 transported fenoterol with 12.9-fold higher capacity but 14.3-fold lower affinity (higher KM) than human OCT1. Human OCT1 transported ipratropium with 5.2-fold higher capacity but 8.4-fold lower affinity than dog OCT1. Compared to human OCT2, dog OCT2 showed 10-fold lower transport of fenoterol and butylscopolamine. In conclusion, the functional characterization of dog OCT1 and OCT2 reported here may have implications when using dogs as pre-clinical models as well as for drug therapy in dogs.


Assuntos
Proteínas de Transporte de Cátions Orgânicos , Transportador 1 de Cátions Orgânicos , Animais , Cátions , Clonagem Molecular , Cães , Fenoterol , Células HEK293 , Humanos , Camundongos , Proteínas de Transporte de Cátions Orgânicos/genética , Transportador 1 de Cátions Orgânicos/genética , Transportador 2 de Cátion Orgânico/genética , Especificidade da Espécie
5.
Front Pharmacol ; 12: 661480, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025422

RESUMO

Organic cation transporter 1 (OCT1, SLC22A1) is localized in the sinusoidal membrane of human hepatocytes and mediates hepatic uptake of weakly basic or cationic drugs and endogenous compounds. Common amino acid substitutions in OCT1 were associated with altered pharmacokinetics and efficacy of drugs like sumatriptan and fenoterol. Recently, the common splice variant rs35854239 has also been suggested to affect OCT1 function. rs35854239 represents an 8 bp duplication of the donor splice site at the exon 7-intron 7 junction. Here we quantified the extent to which this duplication affects OCT1 splicing and, as a consequence, the expression and the function of OCT1. We used pyrosequencing and deep RNA-sequencing to quantify the effect of rs35854239 on splicing after minigene expression of this variant in HepG2 and Huh7 cells and directly in human liver samples. Further, we analyzed the effects of rs35854239 on OCT1 mRNA expression in total, localization and activity of the resulting OCT1 protein, and on the pharmacokinetics of sumatriptan and fenoterol. The 8 bp duplication caused alternative splicing in 38% (deep RNA-sequencing) to 52% (pyrosequencing) of the minigene transcripts when analyzed in HepG2 and Huh7 cells. The alternatively spliced transcript encodes for a truncated protein that after transient transfection in HEK293 cells was not localized in the plasma membrane and was not able to transport the OCT1 model substrate ASP+. In human liver, however, the alternatively spliced OCT1 transcript was detectable only at very low levels (0.3% in heterozygous and 0.6% in homozygous carriers of the 8 bp duplication, deep RNA-sequencing). The 8 bp duplication was associated with a significant reduction of OCT1 expression in the human liver, but explained only 9% of the general variability in OCT1 expression and was not associated with significant changes in the pharmacokinetics of sumatriptan and fenoterol. Therefore, the rs35854239 variant only partially changes splicing, causing moderate changes in OCT1 expression and may be of only limited therapeutic relevance.

6.
Drug Metab Dispos ; 48(12): 1380-1392, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33037045

RESUMO

The most commonly used oral antidiabetic drug, metformin, is a substrate of the hepatic uptake transporter OCT1 (gene name SLC22A1). However, OCT1 deficiency leads to more pronounced reductions of metformin concentrations in mouse than in human liver. Similarly, the effects of OCT1 deficiency on the pharmacokinetics of thiamine were reported to differ between human and mouse. Here, we compared the uptake characteristics of metformin and thiamine between human and mouse OCT1 using stably transfected human embryonic kidney 293 cells. The affinity for metformin was 4.9-fold lower in human than in mouse OCT1, resulting in a 6.5-fold lower intrinsic clearance. Therefore, the estimated liver-to-blood partition coefficient is only 3.34 in human compared with 14.4 in mouse and may contribute to higher intrahepatic concentrations in mice. Similarly, the affinity for thiamine was 9.5-fold lower in human than in mouse OCT1. Using human-mouse chimeric OCT1, we showed that simultaneous substitution of transmembrane helices TMH2 and TMH3 resulted in the reversal of affinity for metformin. Using homology modeling, we suggest several explanations, of which a different interaction of Leu155 (human TMH2) compared with Val156 (mouse TMH2) with residues in TMH3 had the strongest experimental support. In conclusion, the contribution of human OCT1 to the cellular uptake of thiamine and especially of metformin may be much lower than that of mouse OCT1. This may lead to an overestimation of the effects of OCT1 on hepatic concentrations in humans when using mouse as a model. In addition, comparative analyses of human and mouse orthologs may help reveal mechanisms of OCT1 transport. SIGNIFICANCE STATEMENT: OCT1 is a major hepatic uptake transporter of metformin and thiamine, but this study reports strong differences in the affinity for both compounds between human and mouse OCT1. Consequently, intrahepatic metformin concentrations could be much higher in mice than in humans, impacting metformin actions and representing a strong limitation of using rodent animal models for predictions of OCT1-related pharmacokinetics and efficacy in humans. Furthermore, OCT1 transmembrane helices TMH2 and TMH3 were identified to confer the observed species-specific differences in metformin affinity.


Assuntos
Metformina/farmacocinética , Transportador 1 de Cátions Orgânicos/metabolismo , Tiamina/farmacocinética , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Células HEK293 , Hepatócitos , Humanos , Fígado/enzimologia , Masculino , Camundongos , Transportador 1 de Cátions Orgânicos/genética , Transportador 1 de Cátions Orgânicos/ultraestrutura , Conformação Proteica em alfa-Hélice/genética , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/ultraestrutura , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Relação Estrutura-Atividade
7.
Am J Obstet Gynecol ; 213(4): 515.e1-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26116873

RESUMO

OBJECTIVE: The objective of the study was to evaluate success and safety of intrauterine device (IUD) placement in a large cohort of adolescents. STUDY DESIGN: We examined the medical records of patients aged 13-24 years at the Children's Hospital Colorado Adolescent Family Planning Clinic with at least 1 attempt at IUD placement. We abstracted demographic, reproductive, and procedural variables. The primary outcome was successful placement at first IUD insertion visit. We compared nulliparous with parous adolescents and patients younger than 18 years with those 18 years of age and older. RESULTS: Between April 2009 and December 2011, 1177 adolescent women aged 13-24 years (mean age 20.8 ± 2.5 years) had an attempted IUD placement, 1012 (86%) of which were with an advanced practice clinician. The first attempt was successful for 1132 women (96.2%). The first-attempt success rate was 95.8% for nulliparous women and 96.7% for parous women (P = .45). The first-attempt success rate was 95.5% (n = 169) for women aged 13-17 years compared with 96.3% (n = 963) for women aged 18-24 years (P = .6). Only 1.8% (n = 21) of all first-attempt successful insertions required ancillary measures. Of the 45 patients with a failed first insertion attempt, 40% (n = 18) had a second attempt with a physician, of which 78% (n = 14) were successful. Within the first 6 months of IUD placement, no perforations were identified and 24 patients (3.0%) expelled the IUD. Insertion failures and IUD expulsions were not related to IUD type, age, or parity. CONCLUSION: Intrauterine devices can be inserted in nulliparous adolescents of any age with similar success to parous adolescents, by both physicians and advanced practice clinicians. Inability to provide ancillary measures such as paracervical block or cervical dilation should not limit access to this first-line contraceptive method.


Assuntos
Dispositivos Intrauterinos , Paridade , Implantação de Prótese/métodos , Adolescente , Prática Avançada de Enfermagem , Fatores Etários , Estudos de Coortes , Feminino , Ginecologia , Humanos , Expulsão de Dispositivo Intrauterino , Dispositivos Intrauterinos de Cobre , Dispositivos Intrauterinos Medicados , Estudos Retrospectivos , Adulto Jovem
8.
J Chem Phys ; 141(1): 014101, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25005271

RESUMO

While the use of Frenkel-type models for semiconducting polymer assemblies and related molecular aggregates is well established, the direct parametrization of such models based on electronic structure data is attempted less frequently. In this work, we develop a systematic mapping procedure which is adapted to J-type and H-type homo-aggregate systems. The procedure is based upon the analytic solution of an inverse eigenvalue problem for an effective Frenkel Hamiltonian with nearest-neighbor couplings. Vibronic interactions are included for both site-local and site-correlated modes. For illustration, an application is presented to the excited-state ab initio potential energy surfaces (PESs) of an oligothiophene octamer. The procedure performs a pointwise mapping of the PESs of oligomers of arbitrary chain length n, provided that the electronic ground state and any two of the n lowest adiabatic states of the excitonic manifold of interest are known. These three states are reproduced exactly by the procedure while the remaining n - 2 states of the excitonic manifold can be predicted. Explicit conditions are derived permitting to verify whether a given data set is compatible with the effective Frenkel model under study.

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