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1.
BMC Womens Health ; 24(1): 457, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152443

RESUMO

BACKGROUND: Leukemia, as one of the most common pediatric cancers, has negatively affected many children around the world. Parents often experience increased feeling of distress shortly after being informed about their child's diagnosis. The distress experienced by parents can adversely affect various aspects of their life. This study aimed to develop an understanding of the lived experience of the mothers whose children suffer from leukemia in Shiraz, Iran. METHODS: This phenomenological study was performed from April to August 2023, and 10 people were selected as participants by purposive sampling. In-depth and semi-structured interviews were performed for collecting the data. RESULTS: The participants' lived experiences during their children's leukemia were classified into five main categories, namely behavioral problems, spiritual issues, psychological problems, issues related to treatment, and economic matters. CONCLUSION: Knowing the experiences of parents, especially mothers, in managing and planning for the care of these children seems essential.


Assuntos
Leucemia , Mães , Pesquisa Qualitativa , Humanos , Irã (Geográfico) , Mães/psicologia , Feminino , Adulto , Leucemia/psicologia , Criança , Masculino , Estresse Psicológico/psicologia , Estresse Psicológico/etiologia , Pessoa de Meia-Idade , Pré-Escolar
2.
J World Fed Orthod ; 11(1): 29-35, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728153

RESUMO

BACKGROUND: Simulation and prediction can facilitate the decision between an extraction versus nonextraction treatment plan. This study aimed to assess the accuracy of Dolphin Imaging software in predicting profile changes in class I borderline cases. METHODS: In this retrospective study, class I borderline patients (i.e., both extraction and nonextraction treatment plans were possible for them) aged 15-35 years were enrolled. All of the cephalometric analyses were done by Dolphin Imaging software, version 11.8 Premium. The initial cephalograms were superimposed on initial photographs. The final values for the 7 angular and linear landmarks of the upper and lower incisors were extracted from post-treatment cephalograms and inserted in the "Goals" tab of the Dolphin Imaging software. Post-treatment images of patients were simulated. Final post-treatment photographs were superimposed on the simulated pictures. The differences between the real and simulated pictures were calculated in relation to the reference lines. The P value was set at 0.05. RESULTS: A total of 70 patients (36 with tooth extraction, and 34 without tooth extraction) were included. In the extraction group, the horizontal position of both lips was predicted to be significantly more protruded than it actually was, whereas in the nonextraction group, the only difference between the simulated and actual results was that the vertical position of the lower lip, which was simulated as being more inferior than it actually was. CONCLUSIONS: Despite the statistically significant differences between the real and simulated pictures, the differences were small and clinically insignificant. Prediction via Dolphin Imaging software can be an appropriate guide in extraction-nonextraction borderline cases.


Assuntos
Face , Software , Cefalometria/métodos , Queixo/anatomia & histologia , Face/anatomia & histologia , Humanos , Estudos Retrospectivos
3.
Anal Chem ; 92(16): 10952-10956, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32693576

RESUMO

Enzyme-linked immunosorbent assay (ELISA) is a widely used technique for detecting and quantifying target analytes in clinical and research laboratories. One of the main drawbacks of ELISA is the involvement of multiple washing steps that desorbs the capture antigen/antibody off the polystyrene plate, thereby producing inconsistent and erroneous data. To overcome the problem of desorption, we hypothesized that gelatin nanoparticles (GelNP) could serve as a "plate-adherent" substrate to irreversibly adhere the capture antigen/antibody of interest. We tested our hypothesis using GelNP-based substrate (Gel-BSA-OHG) to adhere 8-hydroxy-2'-deoxyguanosine (8-OHdG) to the polystyrene plate and assayed this molecule using the ELISA technique. The stability and ELISA performance of Gel-BSA-OHG was evaluated in comparison to the conventional substrate (BSA-OHG). Importantly, the Gel-BSA-OHG substrate was found to be more wash-resistant and consequently resulted in improved sensitivity, accuracy, and precision in the ELISA analysis of 8-OHdG. Finally, the scope of Gel-BSA-OHG substrate-based ELISA for clinical application was demonstrated by validating its ability to detect 8-OHdG in an artificial urine sample with high specificity.


Assuntos
8-Hidroxi-2'-Desoxiguanosina/urina , Ensaio de Imunoadsorção Enzimática/métodos , Gelatina/química , Nanopartículas/química , 8-Hidroxi-2'-Desoxiguanosina/química , Adsorção , Animais , Bovinos , Estudo de Prova de Conceito , Soroalbumina Bovina/química
4.
SLAS Technol ; 23(1): 57-63, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28945974

RESUMO

Foodborne illnesses are a public health concern in the United States and worldwide. Recent outbreaks of Escherichia coli O157:H7 have brought to light the need for improved ways to detect foodborne pathogens and minimize serious outbreaks. Unfortunately, current methods for the detection of foodborne pathogens are time intensive and complex. In this study, we designed a spot immunoassay that uses a UCON-potassium phosphate salt aqueous two-phase system (ATPS) for the preconcentration of O157:H7. This platform was tested with samples of O157:H7 spiked in phosphate-buffered saline and milk. The ATPS was found to improve the detection limit of the spot test, yielding detection at 106 cfu/mL within 30 min. This is the first known application of ATPSs to spot immunoassays. Moreover, detection was successfully achieved without upstream processing or dilution of the sample prior to testing, thereby further simplifying the detection process. This technology's ease of use, sensitivity, and short time to result highlight its potential to advance the spot test as a viable diagnostic tool for foodborne pathogens.


Assuntos
ELISPOT/métodos , Escherichia coli O157/isolamento & purificação , Microbiologia de Alimentos/métodos , Leite/microbiologia , Animais , Sensibilidade e Especificidade , Fatores de Tempo
5.
RSC Adv ; 8(55): 31510-31514, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35548247

RESUMO

We describe a novel synthetic strategy for conjugating HMGA2 siRNA and the HMGA aptamer to the nucleolin aptamer and nucleolin antibody, respectively. Our studies demonstrate that these conjugates inhibit cell proliferation in retinoblastoma cells.

6.
Arch Insect Biochem Physiol ; 93(4): 190-201, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27509382

RESUMO

Silver nanoparticles (AgNPs) have antimicrobial and insecticidal properties and they have been considered for their potential use as insecticides. While they do, indeed, kill some insects, two broader issues have not been considered in a critical way. First, reports of insect-lethal AgNPs are often based on simplistic methods that yield nanoparticles of nonuniform shapes and sizes, leaving questions about the precise treatments test insects experienced. Second, we do not know how AgNPs influence beneficial insects. This work addresses these issues. We assessed the influence of AgNPs on life history parameters of two agricultural pest insect species, Heliothis virescens (tobacco budworm) and Trichoplusia ni (cabbage looper) and a beneficial predatory insect species, Podisus maculiventris (spined soldier bug), all of which act in agroecosystems. Rearing the two pest species on standard media amended with AgNPs led to negligible influence on developmental times, pupal weights, and adult emergence, however, they led to retarded development, reductions in adult weight and fecundity, and increased mortality in the predator. These negative effects on the beneficial species, if also true for other beneficial insect species, would have substantial negative implications for continued development of AgNPs for insect pest management programs.


Assuntos
Dieta , Heterópteros/efeitos dos fármacos , Nanopartículas Metálicas , Mariposas/efeitos dos fármacos , Prata/toxicidade , Animais , Feminino , Heterópteros/genética , Heterópteros/crescimento & desenvolvimento , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Masculino , Nanopartículas Metálicas/toxicidade , Mariposas/genética , Mariposas/crescimento & desenvolvimento , Ninfa/efeitos dos fármacos , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Controle Biológico de Vetores , Pupa
7.
Contrast Media Mol Imaging ; 10(3): 188-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25169942

RESUMO

Gold nanomaterials (AuNPs) represent a promising new class of contrast agents for X-ray computed tomographic (CT) imaging in both research and clinical settings. These materials exhibit superior X-ray absorption properties compared with other iodinated agents, and thus require lower injection doses. Gold is nonimmunogenic and therefore contributes to safety profile in living specimens. Unfortunately, most reports on the use of AuNPs as X-ray CT enhancers only demonstrate marginal enhancement of the intended anatomical structure. In this study, we demonstrate the dramatic properties of gold nanorods (GNR) to serve as robust X-ray CT contrast-enhancing agent for selective imaging of the spleen. These organ-specific uptake properties were delineated by performing longitudinal CT imaging of living mice that were dosed with GNR at 2 day intervals. Rapid uptake in spleen was noted within 12 h of first systemic administration with a change in contrast enhancement of 90 Hounsfield units (ΔHU = 90) and with two subsequent injections a total contrast enhancement of over 200 HU was observed. The resulting images provide excellent contrast that will enable the detailed anatomical visualization and study of a range of pre-clinical models of spleen disease including infection and cancer.


Assuntos
Meios de Contraste/química , Ouro/química , Nanotubos/química , Baço/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Animais , Cetrimônio , Compostos de Cetrimônio/química , Fígado/diagnóstico por imagem , Masculino , Camundongos , Microscopia Eletrônica de Transmissão
8.
J Biomed Nanotechnol ; 10(3): 383-92, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24730234

RESUMO

The goal of our study was to demonstrate the utility of nanocrystalline gold as an X-ray contrast agent for imaging tumor in living subjects. Even though significant progress has been achieved in this area by researchers, clinical translation remains challenging. Here, we investigated biocompatible gum Arabic stabilized gold nanocrystals (GA-AuNPs) as X-ray contrast agent in tumor bearing mice and dog. Single intratumoral injections of GA-AuNP resulted in X-ray contrast change of -26 HU in the tumor region after 1 hour post-injection period. Subsequently, five intratumoral injections were performed in the mice. The change in CT number in tumor region is not progressive; rather it reaches a saturation point after fourth injection. These data suggested that accumulation of GA-AuNP reaches a threshold limit within a short time period (5 h), and is retained in the tumor tissue for the rest of the period of investigation. A pilot study was conducted in a client-owned dog presented with collision tumor of thyroid carcinoma and osteosarcoma. In this study, GA-AuNP was injected intratumorally in dog and a contrast enhancement of 12 deltaHU was observed. The CT images of both mice and dog clearly demonstrated that GA-AuNP was effectively distributed and retained throughout the tumor site. The CT data obtained by the present study would provide the crucial dosimetry information for strategic therapy planning using this construct. Both mice and dog did not show any clinical changes, thereby confirming that GA-AuNP did not induce toxicity and can be explored for future clinical applications.


Assuntos
Meios de Contraste , Ouro , Nanopartículas Metálicas , Neoplasias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Animais , Cães , Avaliação Pré-Clínica de Medicamentos , Feminino , Goma Arábica/química , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias/terapia , Imagens de Fantasmas , Prognóstico , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/veterinária , Células Tumorais Cultivadas
9.
Chem Commun (Camb) ; 50(25): 3281-4, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24480799

RESUMO

In this communication, we describe a novel synthetic method for fabricating multicomponent gold nanoparticles containing both gallium ions and biomolecules on the surface. Detailed compositional analysis, using STEM-HAADF and EELS spectroscopy, confirmed the crystalline nature of gold and chelation of gallium ions. The presence of the biomolecule was validated using conventional ELISA.


Assuntos
Quelantes/química , Gálio/química , Ouro/química , Nanopartículas Metálicas/química , Ácido Pentético/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quelantes/farmacologia , Gálio/farmacologia , Ouro/farmacologia , Humanos , Nanopartículas Metálicas/administração & dosagem , Ácido Pentético/farmacologia
10.
Bioorg Med Chem Lett ; 24(1): 317-24, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24295787

RESUMO

Although dual inhibition of Cyclooxygenase-2 (COX-2) and 5-Lipoxygenase (5-LOX) enzymes is highly effective than targeting COX or LOX alone, there are only a few reports of examining such compounds in case of colorectal cancers (CRC). In the present work we report that the novel di-tert-butyl phenol-based dual inhibitors DTPSAL, DTPBHZ, DTPINH, and DTPNHZ exhibit significant cytotoxicity against human CRC cell lines. Molecular docking studies revealed a good fit of these compounds in the COX-2 and 5-LOX protein cavities. The inhibitors show significant inhibition of COX-2 and 5-LOX activities and are effective against a panel of human colon cancer cell lines including HCA-7, HT-29, SW480 and intestinal Apc10.1 cells as well as the hyaluronan synthase-2 (Has2) enzyme over-expressing colon cancer cells, through inhibition of the Hyaluronan/CD44v6 cell survival pathway. Western blot analysis and qRT-PCR analyses indicated that the di-tert-butyl phenol-based dual inhibitors reduce the expression of COX-2, 5-LOX, and CD44v6 in human colon cancer HCA-7 cells, while the combination of CD44v6shRNA and DTPSAL has an additional inhibitory effect on CD44v6 mRNA expression. The synergistic inhibitory effect of Celecoxib and Licofelone on CD44v6 mRNA expression suggests that the present dual inhibitors down-regulate cyclooxygenase and lipoxygenase enzymes through CD44v6. The compounds also exhibited enhanced antiproliferative potency compared to standard dual COX/LOX inhibitor, viz. Licofelone. Importantly, the HA/CD44v6 antagonist CD44v6shRNA in combination with synthetic compounds had a sensitizing effect on the cancer cells which enhanced their antiproliferative potency, a finding which is crucial for the anti-proliferative potency of the novel synthetic di-tert-butyl phenol based dual COX-LOX inhibitors in colon cancer cells.


Assuntos
Antineoplásicos/farmacologia , Araquidonato 5-Lipoxigenase/metabolismo , Ciclo-Oxigenase 2/metabolismo , Hidrazonas/farmacologia , Inibidores de Lipoxigenase/síntese química , Inibidores de Lipoxigenase/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Inibidores de Lipoxigenase/química , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
11.
Artigo em Inglês | MEDLINE | ID: mdl-23770498

RESUMO

Novel N(3)-substituted 9,10-Phenanthrenequinone thiosemicarbazones and their copper, nickel and palladium complexes are structurally characterized and reported along with the single crystal X-ray structures of three ligands and one nickel complex. All compounds were evaluated for their antiproliferative potential against Triple Negative Breast Cancer (TNBC) cells which have poor prognosis and no effective drugs to treat with. All compounds exhibited antiproliferative activity against these cells. Among the metal complexes evaluated, redox active copper complexes were found to be more potent. The possible mechanism for such enhanced activity can be attributed to the generation of oxidative stress, which was amenable for targeting through metal complexation.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Fenantrenos/farmacologia , Tiossemicarbazonas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/química , Mama/citologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Cobre/química , Cobre/farmacologia , Feminino , Humanos , Modelos Moleculares , Fenantrenos/química , Tiossemicarbazonas/química
12.
Anal Chem ; 84(21): 9478-84, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-23004345

RESUMO

In this paper, we describe a novel strategy for the fabrication of a nanosensor for detecting luteinizing hormone (LH) of sheep using a gold nanoparticle-peptide conjugate. A new peptide sequence "CDHPPLPDILFL" (leutinizing hormone peptide, LHP) has been identified, using BLAST and Clustal W analysis, to detect antibody of LH (sheep). LHP has been synthesized and characterized, and their affinity toward anti-LH was established using enzyme linked immunosorbant assay (ELISA) technique. The thiol group in LHP directly binds with gold nanoparticles (AuNPs) to yield AuNP-LHP construct. Detailed physicochemical analysis of AuNP-LHP construct was determined using various analytical techniques. Nanosensor using gold nanoparticle peptide conjugate was developed on the basis of competitive binding of AuNP-LHP and LH toward anti-LH. Nitrocellulose membrane, precoated with anti-LH, was soaked in the mixture of AuNP-LHP and sample of analysis (LH). In the absence of LH (sheep), anti-LH coated on the membrane binds with AuNP-LHP, leading to a distinctive red color, while in the presence of LH, no color appeared in the membrane due to the interaction of anti-LH with LH thereby preventing the binding of AuNP-LHP with membrane bound anti-LH. The sensor assay developed in this study can detect LH (sheep) up to a minimal concentration of ∼50 ppm with a high degree of reproducibility and selectivity. The gold-nanoparticle-peptide based nanosensor would be a simple, portable, effective, and low cost technique for infield applications.


Assuntos
Técnicas Biossensoriais/instrumentação , Ouro/química , Hormônio Luteinizante/análise , Nanopartículas Metálicas/química , Sequência de Aminoácidos , Animais , Ensaio de Imunoadsorção Enzimática , Desenho de Equipamento , Hormônio Luteinizante/sangue , Hormônio Luteinizante/química , Oligopeptídeos/química , Propriedades de Superfície
13.
Bioorg Med Chem Lett ; 22(9): 3172-6, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22475559

RESUMO

Currently used anti-tubercular drugs target actively growing Mycobacterium tuberculosis (Mtb) but there are no current therapies targeting persistent mycobacteria. Isocitrate lyase (ICL) is an important enzyme of the glyoxylate shunt pathway used by Mtb for sustaining intracellular infection in inflammatory macrophages under conditions of stress such as nutrient depletion and anaerobic metabolism. Since the humans do not possess this enzyme it constitutes an attractive target for selective drug design. Present work describes synthesis and structural characterization of pyruvate-isoniazid conjugates and their copper complexes with potent anti-tubercular activities against M. tuberculosis H37Rv.


Assuntos
Antituberculosos/síntese química , Cobre/química , Isocitrato Liase/antagonistas & inibidores , Isoniazida/análogos & derivados , Piruvatos/síntese química , Antibacterianos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Isoniazida/síntese química , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia
14.
Inorganica Chim Acta ; 372(1): 333-339, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21709763

RESUMO

Gold-thioguanine nanoconjugates (AuNP-TG) of size 3-4 nm were synthesized and the ratio between gold and 6-Thioguanine (TG) was estimated as ~1:1.5 using a cyanide digestion method and confirmed by flame atomic absorption spectroscopic analysis. AuNP-TG constructs showed high in vitro stability under different pH conditions and biologically relevant solutions for a period of 24 hours. Reaction of AuNP-TG with europium or platinum salts resulted in the formation of organized self-assembled metallo-networks.

15.
J Nanosci Nanotechnol ; 10(2): 719-25, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20352709

RESUMO

A one-step method for synthesis of bioconjugated gold nanoparticles is reported. A non-toxic and biocompatible phosphorus based reducing agent was used for reduction of gold (III) and formation of nanoparticles. Physicochemical properties of protein-A stabilized gold nanoparticls were investigated. Result of immunoassay experiments confirmed the potential of the synthesized anti-protein-A conjugated gold nanoparticles for use as a simple and inexpensive test for quantitative screening of protein-A samples.


Assuntos
Ouro , Nanopartículas Metálicas , Nanotecnologia , Proteínas/química
16.
J Inorg Biochem ; 101(10): 1517-24, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17689613

RESUMO

Copper conjugates of Schiff base derivatives of nimesulide (1), a well-known cyclooxygenase-2 (COX-2) inhibitor, were synthesized, structurally characterized and evaluated for their COX selectivity indices and cytotoxicities on pancreatic tumor, BxPC-3 (COX-2 positive) and MiaPaCa (COX-2 negative) cell lines. Copper conjugates exhibit distorted square planar geometries as revealed by the single crystal X-ray structure determination of Cu(L1)(2) and show significant growth inhibition in both cell lines (IC50 values 3-26 microM for COX-2 positive and 5-9 microM for COX-2 negative cell line) than the parent nimesulide (35 microM for COX-2 positive and >100 microM for COX-2 negative cell line). The mechanistic pathway for the biological activity involves inhibition of vascular endothelial growth factor (VEGF) and COX inhibition, as well as down regulation of antiapoptotic Bcl-2 and Bcl-(XL) proteins.


Assuntos
Cobre/química , Ciclo-Oxigenase 2/química , Proteínas Proto-Oncogênicas c-bcl-2/química , Bases de Schiff , Sulfonamidas/química , Fator A de Crescimento do Endotélio Vascular/química , Animais , Linhagem Celular Tumoral , Proliferação de Células , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Modelos Moleculares , Espectrofotometria Infravermelho
17.
J Inorg Biochem ; 99(7): 1526-31, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15927263

RESUMO

Ni(II) complexes of ortho-naphthaquinone thiosemicarbazone and semicarbazone were synthesized and spectroscopically characterized. The X-ray crystal structure of both the complexes describe a distorted octahedral coordination with two tridentate mono-deprotonated ligands. In vitro anticancer studies on MCF-7 human breast cancer cells reveal that the semicarbazone derivative along with its nickel complex is more active in the inhibition of cell proliferation than the thiosemicarbazone analogue.


Assuntos
Antineoplásicos , Naftoquinonas/química , Níquel/química , Compostos Organometálicos , Semicarbazonas/química , Tiossemicarbazonas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
18.
Inorg Chem ; 44(5): 1154-6, 2005 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-15732942

RESUMO

The crystal structure of the potential antitumor metal compound, viz. chloro, mono(phenanthrenequinone thiosemicarbazonato) palladium(II) dimethyl formamide solvate, is reported. The central palladium(II) atom is in a square planar environment provided by the tridentate, monoanionic thiosemicarbazone ligand and the ancillary chloride ion. The compound exhibited remarkable activity against drug-sensitive and drug-resistant breast cancer cell lines and was relatively nontoxic toward the normal mammary epithelial cells. The drug-induced killing effect against breast cancer cell lines was predominantly mediated via apoptosis, a physiologic form of cell death.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Fenantrenos/química , Fenantrenos/farmacologia , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular
19.
Toxicol Appl Pharmacol ; 197(1): 40-8, 2004 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15126073

RESUMO

We have investigated the antitumor functions and mechanisms of 1,2-naphthoquinone-2-thiosemicarbazone (NQTS) and its metal complexes (Cu(2+), Pd(2+), and Ni(2+)) against MCF-7 human breast cancer cells. The cells were dosed with these complexes at varying concentrations, and cell viability was measured by a sulforhodamine B (SRB) method. To study mechanisms of action, the complexes were incubated with topoisomerase II (topo II) and supercoiled DNA, linear DNA, nicked open DNA, and relaxed DNA were detected by agarose gel electrophoresis. The results revealed that these complexes are effective antitumor chemicals in inhibiting MCF-7 cell growth, with Ni-NQTS being the most effective among the complexes studied. Our data also indicated that Ni-NQTS is more effective than the commercial antitumor drug, etoposide, based on IC(50) values. The mechanistic study of action showed that metal complexes of NQTS, NQ, and NQTS can only stabilize the single-strand nicked DNA, but not double-strand breakage intermediates. In addition, metal derivatives of these ligands, but not the parent NQ and NQTS, exerted an antagonizing effect on topoisomerase II activity. In summary, chemicals with or without metal derivatives might possess different chemical-topoisomerase II-DNA interactions.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Metais/farmacologia , Naftoquinonas/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , DNA de Neoplasias/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Indicadores e Reagentes , Inibidores da Topoisomerase II
20.
J Inorg Biochem ; 95(4): 306-14, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12818801

RESUMO

The thiosemicarbazone derivative of 9,10-phenanthrenequinone, 1, and its metal complexes were synthesized. The X-ray crystal structure for 1 confirms the presence of the E tautomeric arrangement in this compound. Its copper complex shows 1:1 stoichiometry while nickel and cobalt compounds show 1:2 stoichiometry. The X-ray crystal structure of the nickel complex indicates two tridentate ligands coordinating in the thiolato form yielding an octahedral geometry for the 'mer' isomer. The copper complex exhibits maximum antiproliferative activity against human breast cancer cell-line, T47D probably due to inhibition of steroid binding to the cognitive receptor or by preventing dimerization of the estrogen receptor.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Metais/química , Fenantrenos/síntese química , Fenantrenos/farmacologia , Tiossemicarbazonas/síntese química , Tiossemicarbazonas/farmacologia , Antineoplásicos/química , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cristalografia por Raios X , Eletroquímica , Humanos , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Magnetismo , Modelos Moleculares , Estrutura Molecular , Fenantrenos/química , Análise Espectral , Tiossemicarbazonas/química
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