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1.
RSC Adv ; 14(8): 5340-5350, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38348299

RESUMO

Applications of 9-aminoacridine (9aa) and its derivatives span fields such as chemistry, biology, and medicine, including anticancer and antimicrobial activities. Protonation of such molecules can alter their bioavailability as weakly basic drugs like aminoacridines exhibit reduced solubility at high pH levels potentially limiting their effectiveness in patients with elevated gastric pH. In this study, we analyse the influence of protonation on the electronic characteristics of the molecular organic crystals of 9-aminoacridine. The application of quantum crystallography, including aspherical atom refinement, has enriched the depiction of electron density in the studied systems and non-covalent interactions, providing more details than previous studies. Our experimental results, combined with a topological analysis of the electron density and its Laplacian, provided detailed descriptions of how protonation changes the electron density distribution around the amine group and water molecule, concurrently decreasing the electron density at bond critical points of N/O-H bonds. Protonation also alters the molecular architecture of the systems under investigation. This is reflected in different proportions of the N⋯H and O⋯H intermolecular contacts for the neutral and protonated forms. Periodic DFT calculations of the cohesive energies of the crystal lattice, as well as computed interaction energies between molecules in the crystal, confirm that protonation stabilises the crystal structure due to a positive synergy between strong halogen and hydrogen bonds. Our findings highlight the potential of quantum crystallography in predicting crystal structure properties and point to its possible applications in developing new formulations for poorly soluble drugs.

2.
Sci Rep ; 14(1): 2388, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287191

RESUMO

The aim of this study was to determine the influence of age and gender on the incidence of calcification in laryngeal cartilage diagnosed on lateral cephalometric radiographs routinely taken for orthodontic diagnosis. The lateral cephalometric radiographs of 957 patients who met the study criteria were analyzed from among the 1000 lateral radiographs originally collected. The images were evaluated independently by two investigators. Given the dichotomous dependent variable (calcification or no calcification), a mixed logistic regression model was used to test how age and gender affected calcification. The effect of age and gender reliably determined the likelihood of laryngeal cartilage calcification. The greatest differences in the degree of calcification by gender were found at ages 20-25 years. The degree of calcification increased with age, reaching 100% in women at age 30 and in men at age 50. In women, the degree of calcification was higher than in men from the age of 13 years and levelled off at the age of 50 years. The interrater agreement was strong k = 0.97, z = 30.0, p < .001. Calcification can be detected by orthodontists trained in lateral cephalogram analysis and can be used as a screening or diagnostic tool to detect calcified areas in the larynx.


Assuntos
Calcinose , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Adolescente , Calcinose/diagnóstico por imagem , Calcinose/epidemiologia , Radiografia , Cefalometria , Cartilagens Laríngeas , Cartilagem
3.
Artigo em Inglês | MEDLINE | ID: mdl-37622396

RESUMO

BACKGROUND: Anatomical research based on deceased body specimens is a time-consuming process that requires a great deal of skill and time to perform correctly. Three-dimensional medical image analysis is an excellent tool for anatomic evaluation, but it often includes patients with comorbidities in the study group, which can skew the results. The purpose of this study was to develop and evaluate methods for anatomic research based on postmortem contrast-enhanced computed tomography angiography 3D reconstruction of the celiac trunk. MATERIALS AND METHODS: Postmortem contrast-enhanced computed tomography angiography of 105 (28.6% female, age 50.8±18.7) decedents without abdominal trauma or tumor was analyzed. The abdominal portion of the aorta and the celiac trunk with its branches were reconstructed and evaluated. The type of celiac trunk was evaluated. The results were analyzed. RESULTS: The celiac trunk, splenic artery, and common hepatic artery were visualized in all cases. The left gastric artery was visible in 97.1% of cases. The dorsal pancreatic artery was visualized in 61.0% of cases. The most common type of celiac trunk was 1 (88.6%), and the rarest types were 2, 3, and 6 (1.0%). We observed 4 morphologies of the truncus celiacus that did not fit the classification presented previously. CONCLUSIONS: This study has demonstrated that three-dimensional reconstruction of postmortem contrast-enhanced computed tomography is an excellent tool for performing accurate morphometric analyzes for anatomic research purposes. This method can serve as a source for anatomic studies in the healthy population.

4.
Molecules ; 28(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37570871

RESUMO

Cyclic dipeptides with two intramolecular peptide bonds forming a six-membered 2,5-diketopiperazine ring are gaining significant attention due to their biological and chemical properties. Small changes in the local geometry of such molecules (from cis to trans) can lead to significant structural differences. This work presents the results of a study of cyclo(l-Cys-d-Cys), a dipeptide comprising two cysteine molecules in opposite chiral configurations, with the functional groups situated at both sides of the diketopiperazine ring. X-ray diffraction (XRD) experiment revealed that the molecule crystallises in the P-1 space group, which includes the centre of inversion. The IR and Raman vibrational spectra of the molecule were acquired and interpreted in terms of the potential energy distribution (PED) according to the results of density functional theory (DFT) calculations. The DFT-assisted analysis of energy frameworks for the hydrogen bond network within molecular crystals was performed to support the interpretation of X-ray structural data. The optimisation of the computational model based on three-molecule geometry sections from the crystallographic structure, selected to appropriately reflect the intermolecular interactions responsible for the formation of 1D molecular tapes in cyclo(l-Cys-d-Cys) crystal, allowed for better correspondence between theoretical and experimental vibrational spectra. This work can be considered the first complete structural characterisation of cyclo(l-Cys-d-Cys), complemented via vibrational spectroscopy results with full band assignment aided with the use of the DFT method.

5.
Carbohydr Res ; 531: 108861, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37356236

RESUMO

2-Deoxy-d-glucose (2-DG), a compound known to interfere with d-glucose and d-mannose metabolism, has been tested as a potential anticancer and antiviral agent. Preclinical and clinical studies focused on 2-DG have highlighted several limitations related to 2-DG drug-like properties, such as poor pharmacokinetic properties. To overcome this problem, we proposed design and synthesis of novel 2-DG prodrugs that subsequently could be tested using a variety of biochemical and molecular methods. We narrowed here our focus to esters of 2-DG as potential prodrugs based on the hypothesis that ubiquitous esterases will regenerate 2-DG, leading to increased circulation time of drug and adequate organ and tumor penetration. Testing this hypothesis in vitro and, especially, in vivo requires significant amounts of respective pure mono- and previously unknown di-acetylated water-soluble derivatives of 2-DG. Development of their efficient and practical method of synthesis was imperative. We describe novel facile and scalable syntheses of seven selectively acetylated water-soluble derivatives of 2-DG and present a detailed 1H and 13C NMR analysis of all final products. X-ray diffraction analysis has been performed for compound WP1122 that was selected for detailed preclinical and subsequent clinical evaluation as potential anticancer or antiviral agent.


Assuntos
Glucose , Pró-Fármacos , Glucose/química , Antimetabólitos , Manose/química , Desoxiglucose/química , Antivirais/farmacologia
6.
Dalton Trans ; 52(6): 1551-1567, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36655722

RESUMO

The first-in-class luminescent dinucleoside phosphate analogs with a [Re2(µ-Cl)2(CO)6(µ-pyridazine)] "click" linker as a replacement for the natural phosphate group are reported together with the synthesis of luminescent adenosine and thymidine derivatives having the [Re2(µ-Cl)2(CO)6(µ-pyridazine)] entity attached to positions 5' and 3', respectively. These compounds were synthesized by applying inverse-electron-demand Diels-Alder and copper(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition reactions in three or four steps. The obtained compounds exhibited orange emission (λPL ≈ 600 nm, ΦPL ≈ 0.10, and τ = 0.33-0.61 µs) and no toxicity (except for one nucleoside) to human HeLa cervical epithelioid and Ishikawa endometrial adenocarcinoma cancer cells in vitro. Furthermore, the compounds' ability to inhibit the growth of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacterial strains was moderate and only observed at a high concentration of 100 µM. Confocal microscopy imaging revealed that the "dirhenium carbonyl" dinucleosides and nucleosides localized mainly in the membranous structures of HeLa cells and uniformly inside S. aureus and E. coli bacterial cells. An interesting finding was that some of the tested compounds were also found in the nuclei of HeLa cells.


Assuntos
Nucleosídeos , Piridazinas , Humanos , Nucleosídeos/química , Células HeLa , Fosfatos de Dinucleosídeos , Fosfatos , Escherichia coli , Staphylococcus aureus , Química Click/métodos
7.
Oncol Lett ; 24(5): 410, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36245826

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common types of cancer diagnosed worldwide. After a decade of stagnation, several novel compounds have recently been shown to be effective in the treatment of HCC. Since immunotherapy is associated with important clinical benefits in some, but not all patients, it is essential to identify reliable predictive biomarkers. As the complex interplay between hepatocytes and immune cells is highly dependent on the tumor microenvironment, the tumor microenviroment has been suggested to be an important factor associated with the response to therapy and is currently being extensively investigated. Within this network, several important factors should be highlighted. Most of the cells are hepatocytes, but fibroblasts, endothelial cells, and immune cells are also present. Tumor-infiltrating leukocytes include several populations of cells and each of them plays a role in forming the tumor environment. Some of these cells may have antitumor effects, whereas others may be associated with the progression of the disease. The most important subsets include tumor-associated macrophages, tumor-associated neutrophils, and lymphocytes. These groups are described in the present review. The immune response is controlled by immune checkpoint molecules. One of the most important molecules involved in this checkpoint process seems to be the programmed death-1 (PD-1) receptor, which typically is induced on activated T cells, natural killer (NK) cells, B cells, and antigen-presenting cells. On the other hand, programmed death ligand 1 (PD-L1) is expressed by tumor cells, hepatocytes and hepatic stellate cells, and Kupffer cells or liver sinusoidal cells. Complex interactions between ligands and receptors are dependent on the signals from the microenvironment leading to either cancer development or apoptosis. Evidence from several studies indicates that patients with higher expression levels of PD-L1 on tumor cells or immune cells are more likely to achieve beneficial results from treatment with checkpoint blockers. This review focuses on the basic information regarding the microenvironment and its components, particularly on immune system involvement.

8.
Inorg Chem ; 61(25): 9650-9666, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35699521

RESUMO

Mixed-valence (MV) binuclear ferrocenyl compounds have long been studied as models for testing theories of electron transfer and in attempts to design molecular-scale electronic devices (e.g., molecular wires). In contrary to that, far less attention has been paid to MV binuclear ferrocenes as anticancer agents. Herein, we discuss the synthesis of six 1,2,3-triazole ferrocenyl compounds for combined (spectro)electrochemical, electron paramagnetic resonance (EPR), computational, and anticancer activity studies. Our synthetic approach was based on the copper-catalyzed 1,3-dipolar azide-alkyne cycloaddition reaction and enabled us to obtain in one step compounds bearing either one, two, or three ferrocenyl entities linked to the common 1,2,3-triazole core. Thus, two series of complexes were obtained, which pertain to derivatives of 3'-azido-3'-deoxythymidine (AZT) and 3-azidopropionylferrocene, respectively. Based on the experimental and theoretical data, the two mono-oxidized species corresponding to binuclear AZT and trinuclear 3-azidopropionylferrocene complexes have been categorized as class II mixed-valence according to the classification proposed by Robin and Day. Of importance is the observation that these two compounds are more active against human A549 and H1975 non-small-cell lung cancer cells than their congeners, which do not show MV characteristics. Moreover, the anticancer activity of MV species competes or surpasses, dependent on the cell line, the activity of reference anticancer drugs such as cisplatin, tamoxifen, and 5-fluorouracil. The most active from the entire series of compounds was the binuclear thymidine derivative with the lowest IC50 value of 5 ± 2 µM against lung H1975 cancer cells. The major mechanism of antiproliferative activity for the investigated MV compounds is based on reactive oxygen species generation in cancer cells. This hypothesis was substantiated by EPR spin-trapping experiments and the observation of decreased anticancer activity in the presence of N-acetyl cysteine (NAC) free-radical scavenger.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antineoplásicos/química , Eletrônica , Humanos , Metalocenos , Espécies Reativas de Oxigênio/metabolismo , Triazóis/química
9.
Bioorg Chem ; 125: 105847, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35526436

RESUMO

The knowledge pertaining to the chemistry and biological activity of glycol nucleic acid (GNA) components, like nucleosides and nucleotides, is still very limited. Herein we report on the preparation of the uracil nucleoside (1) and nucleotide ester GNA (2). The compounds are functionalised with a luminescent phenanthrenyl group. In DMSO, 1 and 2 are brightly fluorescent, with emission maxima at 390 nm, nanosecond decay times (0.6 and 0.75 ns, respectively), and quantum yields of ca. 0.2. In the solid phase, they show excimeric emission, with maxima at 495 nm (1) and 432 nm (2), and decay times of 3.7 ns (1) and 2.9 ns (2). The anticancer activity of the GNA components, as well as gemcitabine hydrochloride, used as a reference drug, were examined in vitro against human cancer HeLa and Ishikawa cells, as well as against normal L929 cells, using a battery of biochemical assays. Furthermore, biodistribution imaging studies were carried out in HeLa cells, with luminescence confocal microscopy, which showed that the compounds localized mainly in the lipophilic cellular compartments. Nucleoside (1) and nucleotide ester (2) features two different anticancer activity profiles. At 24 h of treatment, the nucleoside acts mainly as a toxin and induces necrosis in HeLa cells, whereas the nucleotide ester exhibits pro-apoptotic activity. At longer treatment times (72 h), the nucleoside and the reference, gemcitabine hydrochloride, featured almost identical signs of anticancer activity, such as S-phase cell cycle arrest, proliferation inhibition, and apoptosis induction. In view of this data, one can hypothesize that despite the structural differences, the newly obtained phenanthrenyl GNA nucleoside (1) and gemcitabine may share a common mechanism of anticancer activity in HeLa cancer cells. The GNA components were also examined as antiplasmodial agents against Plasmodium falciparum, in vitro. Nucleoside (1) was found to be more potent than nucleotide (2), displaying activity in the low micromolar range. Furthermore, both phenanthrene derivatives were found to display resistance indices at least 9-fold lower than chloroquine diphosphate (CQDP).


Assuntos
Ácidos Nucleicos , Ésteres , Glicóis/química , Células HeLa , Humanos , Ácidos Nucleicos/química , Nucleotídeos , Distribuição Tecidual
10.
IUCrJ ; 9(Pt 2): 298-315, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35371499

RESUMO

Hirshfeld atom refinement (HAR) is one of the most effective methods for obtaining accurate structural parameters for hydrogen atoms from X-ray diffraction data. Unfortunately, it is also relatively computationally expensive, especially for larger molecules due to wavefunction calculations. Here, a fragmentation approach has been tested as a remedy for this problem. It gives an order of magnitude improvement in computation time for larger organic systems and is a few times faster for metal-organic systems at the cost of only minor differences in the calculated structural parameters when compared with the original HAR calculations. Fragmentation was also applied to polymeric and disordered systems where it provides a natural solution to problems that arise when HAR is applied. The concept of fragmentation is closely related to the transferable aspherical atom model (TAAM) and allows insight into possible ways to improve TAAM. Hybrid approaches combining fragmentation with the transfer of atomic densities between chemically similar atoms have been tested. An efficient handling of intermolecular interactions was also introduced for calculations involving fragmentation. When applied in fragHAR (a fragmentation approach for polypeptides) as a replacement for the original approach, it allowed for more efficient calculations. All of the calculations were performed with a locally modified version of Olex2 combined with a development version of discamb2tsc and ORCA. Care was taken to efficiently use the power of multicore processors by simple implementation of load-balancing, which was found to be very important for lowering computational time.

11.
RSC Adv ; 12(14): 8345-8360, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35424802

RESUMO

The structural studies on two bromo-substituted derivatives of 2-deoxy-d-glucose (2-DG), namely 2-deoxy-2-bromo-d-glucose (2-BG) and 2-deoxy-2-bromo-d-mannose (2-BM) are described. 2-DG itself is an inhibitor of hexokinase, the first enzyme in the glycolysis process, playing a vital role in both cancer cell metabolism and viral replication in host cells. Because of that, 2-DG derivatives are considered as potential anti-cancer and anti-viral drugs. An X-ray quantum crystallography approach allowed us to obtain more accurate positions of hydrogen atoms by applying Hirshfeld atom refinement, providing a better description of hydrogen bonding even in the case of data from routine X-ray experiments. Obtained structures showed that the introduction of bromine at the C2 position in the pyranose ring has a minor influence on its conformation but still, it has a noticeable effect on the crystal structure. Bromine imposes the formation of a layered supramolecular landscape containing hydrogen bonds, which involves the bromine atom. Periodic DFT calculations of cohesive and interaction energies (at the B3LYP level of theory) have supported these findings and highlighted energetic changes upon bromine substitution. Based on molecular wavefunction from the refinement, we calculated the electrostatic potential, Laplacian, and ELI-D, and applied them to charge-density studies, which confirmed the geometry of hydrogen bonding and involvement of the bromine atom with these intermolecular interactions. NMR studies in the solution show that both compounds do not display significant differences in their anomeric equilibria compared to 2-DG, and the pyranose ring puckering is similar in both aqueous and solid state.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34360134

RESUMO

BACKGROUND: The COVID-19 pandemic has globally overwhelmed all sectors of life. The fast development of vaccines against COVID-19 has had a significant impact on the course of the pandemic. METHODS: Global data from Google Trends was analyzed for vaccines against flu, BCG, HPV, pneumococcal disease, polio, and COVID-19. The time frame includes the last five-year period starting from 17 April 2016. Multiple training of time series models with back testing, including Holt-Winters forecasting, Exponential Smoothing State Space, Linear model with trend and seasonal components (tlsm), and ARIMA was conducted. Forecasting according to the best fitting model was performed. RESULTS: Correlation analysis did not reveal a decrease in interest in vaccines during the analyzed period. The prediction models provided a short-term forecast of the dynamics of interest for flu, HPV, pneumococcal and polio vaccines with 5-10% growth in interest for the first quarter of 2022 when compared to the same quarter of 2021. CONCLUSIONS: Despite the huge interest in the COVID-19 vaccine, there has not been a detectable decline in the overall interest in the five analyzed vaccines.


Assuntos
COVID-19 , Pandemias , Vacinas contra COVID-19 , Humanos , Vacinas Pneumocócicas , SARS-CoV-2 , Ferramenta de Busca
13.
Int J Mol Sci ; 22(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918425

RESUMO

The results of structural studies on a series of halogen-substituted derivatives of 2-deoxy-D-glucose (2-DG) are reported. 2-DG is an inhibitor of glycolysis, a metabolic pathway crucial for cancer cell proliferation and viral replication in host cells, and interferes with D-glucose and D-mannose metabolism. Thus, 2-DG and its derivatives are considered as potential anticancer and antiviral drugs. X-ray crystallography shows that a halogen atom present at the C2 position in the pyranose ring does not significantly affect its conformation. However, it has a noticeable effect on the crystal structure. Fluorine derivatives exist as a dense 3D framework isostructural with the parent compound, while Cl- and I-derivatives form layered structures. Analysis of the Hirshfeld surface shows formation of hydrogen bonds involving the halogen, yet no indication for the existence of halogen bonds. Density functional theory (DFT) periodic calculations of cohesive and interaction energies (at the B3LYP level of theory) have supported these findings. NMR studies in the solution show that most of the compounds do not display significant differences in their anomeric equilibria, and that pyranose ring puckering is similar to the crystalline state. For 2-deoxy-2-fluoro-D-glucose (2-FG), electrostatic interaction energies between the ligand and protein for several existing structures of pyranose 2-oxidase were also computed. These interactions mostly involve acidic residues of the protein; single amino-acid substitutions have only a minor impact on binding. These studies provide a better understanding of the structural chemistry of halogen-substituted carbohydrates as well as their intermolecular interactions with proteins determining their distinct biological activity.


Assuntos
Desoxiglucose/análogos & derivados , Halogênios/química , Desoxiglucose/metabolismo , Ligantes , Espectroscopia de Ressonância Magnética , Conformação Molecular , Proteínas/metabolismo , Difração de Raios X
14.
Front Oncol ; 11: 662211, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912468

RESUMO

COVID-19 has become the biggest public health problem and one of the most important causes of death in many countries in the world. SARS-CoV-2 infection is most likely to be fatal in elderly patients with concomitant diseases. In this article we present two cases of asymptomatic SARS-CoV-2-positive patients suffering from cancer who were treated with chemotherapy. The first case, a patient with primary mediastinal B-cell lymphoma, shows that confirmed SARS-CoV-2 infection does not have to be a contraindication to chemotherapy. We describe the course of disease and discuss doubts related to the choice of chemotherapy regimen. The second patient was a male with metastatic sigmoid cancer treated with FOLFOX4 as first-line palliative chemotherapy. This case draws attention to asymptomatic SARS-CoV-2 carriers who underwent chemotherapy. Our patient was safely treated with chemotherapy without long break caused by viral infection. It should be remembered that there are asymptomatic carriers among cancer patients and that they may spread infection to others. On the other hand, delaying chemotherapy can cause rapid disease progression and reduce overall survival of our patients.

15.
J Clin Med ; 10(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923491

RESUMO

The aim of this cross-sectional study was to evaluate the electromyographic activity of the superior orbicularis oris muscle both in children surgically treated for bilateral complete cleft lip and palate (BCCLP) as well as in subjects without BCCLP. The study comprised 77 children aged 6.6 to 12.5 years. All the patients with clefts had previously undergone lip and palate surgery. The upper lip electromyographic (EMG) assessments were made with a DAB-Bluetooth device (Zebris Medical GmbH, Germany) at rest, while swallowing saliva, protruding lips and compressing lips. EMG measurements were also made when the subjects produced phonemes /p/, /b/, and /m/ with the vowel /a/. The Mann-Whitney U test was applied to statistically analyze the EMG values. Significantly higher median upper lip EMG activity under working conditions such as swallowing saliva, lip compression, and production of the phoneme /p/ with the vowel /a/ was observed in patients with BCCLP compared to those without a cleft. The results of the study showed that the upper lip muscle activity increases in children with BCCLP when swallowing saliva, compressing lips and during some speech movement tasks. This may be important in the aspect of the effect of surgical lip repair on the craniofacial growth.

16.
Molecules ; 26(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546456

RESUMO

Phosphodiesterase 5 (PDE5) is one of the most extensively studied phosphodiesterases that is highly specific for cyclic-GMP hydrolysis. PDE5 became a target for drug development based on its efficacy for treatment of erectile dysfunction. In the present study, we synthesized four novel analogues of the phosphodiesterase type 5 (PDE5) inhibitor-tadalafil, which differs in (i) ligand flexibility (rigid structure of tadalafil vs. conformational flexibility of newly synthesized compounds), (ii) stereochemistry associated with applied amino acid building blocks, and (iii) substitution with bromine atom in the piperonyl moiety. For both the intermediate and final compounds as well as for the parent molecule, we have established the crystal structures and performed a detailed analysis of their structural features. The initial screening of the cytotoxic effect on 16 different human cancer and non-cancer derived cell lines revealed that in most cases, the parent compound exhibited a stronger cytotoxic effect than new derivatives, except for two cell lines: HEK 293T (derived from a normal embryonic kidney, that expresses a mutant version of SV40 large T antigen) and MCF7 (breast adenocarcinoma). Two independent studies on the inhibition of PDE5 activity, based on both pure enzyme assay and modulation of the release of nitric oxide from platelets under the influence of tadalafil and its analogues revealed that, unlike a reference compound that showed strong PDE5 inhibitory activity, the newly obtained compounds did not have a noticeable effect on PDE5 activity in the range of concentrations tested. Finally, we performed an investigation of the toxicological effect of synthesized compounds on Caenorhabditis elegans in the highest applied concentration of 6a,b and 7a,b (160 µM) and did not find any effect that would suggest disturbance to the life cycle of Caenorhabditis elegans. The lack of toxicity observed in Caenorhabditis elegans and enhanced, strengthened selectivity and activity toward the MCF7 cell line made 7a,b good leading structures for further structure activity optimization and makes 7a,b a reasonable starting point for the search of new, selective cytotoxic agents.


Assuntos
Caenorhabditis elegans/enzimologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Inibidores da Fosfodiesterase 5 , Piperazinas , Tadalafila , Animais , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Humanos , Células MCF-7 , Inibidores da Fosfodiesterase 5/síntese química , Inibidores da Fosfodiesterase 5/química , Inibidores da Fosfodiesterase 5/farmacologia , Piperazinas/síntese química , Piperazinas/química , Piperazinas/farmacologia , Tadalafila/análogos & derivados , Tadalafila/síntese química , Tadalafila/química , Tadalafila/farmacologia
17.
Support Care Cancer ; 29(7): 3767-3771, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33219405

RESUMO

BACKGROUND: Absolute neutrophil count (ANC) below 1.5 G/l or 1 G/l is commonly used as a factor to determine the decision to administer antineoplastic treatment including chemotherapy and novel agents to cancer patients. This practice is based on observations that below this ANC, there is an increased risk of bacterial and fungal infection. This is further based on the assumption that this parameter always correctly reflects the true shortage of these germ-fighting cells in patients. In reality, the circulating pool of neutrophils is only one of four reservoirs (bone marrow, circulating, marginal and tissue pools) and its size is influenced not only by shortage but also by transient shift of cells between these reservoirs. The aim of this study was to evaluate whether repeated blood collection affects ANC in the patient. METHODS: We retrospectively analysed the medical records of cancer patients with 0.8 G/l ≤ ANC < 1.5 G/l in whom CBC was repeated based on the physician's decision, which was done on the same day roughly 2 h after the first one. RESULTS: The patients at the time of repeating CBC had consumed breakfast. In 31 out of 32 patients, ANC exceeded 1 G/l or 1.5 G/l and antineoplastic treatment was administered as originally planned. There were no infectious complications observed. CONCLUSION: Cancer patients should not be fasting prior to blood collection, with the exception of special and rare situations. To achieve the maximum clinical benefit, delays and/or reductions of antineoplastic treatment should be avoided wherever possible. Pseudoneutropenia is an unnecessary reason for postponing chemotherapy.


Assuntos
Refeições/fisiologia , Neoplasias/tratamento farmacológico , Neutropenia/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Crit Rev Oncol Hematol ; 157: 103179, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33302158

RESUMO

According to data provided by WHO (World Health Organization), hepatocellular carcinoma (HCC) is the fourth most common cause of cancer-related deaths worldwide. Since the approval of sorafenib in 2008, several trials have assessed other particles for the treatment of HCC, but few have proven to be effective. ESMO (European Society for Medical Oncology) guidelines have been changed several times recently. This systematic review aims to describe both successful and failed trials of systemic treatments for HCC. Methods: We examined randomized, phase III trials of first- and second-line treatments in adults, identifying 23 fully-published trials and 2 reported as abstracts. The latest advances in immunotherapy were also briefly discussed. Conclusions: The landscape of HCC treatment has changed significantly in recent years. Several small molecule inhibitors currently form the core of HCC treatment; however, immunotherapy is now emerging as a promising treatment option.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/terapia , Humanos , Imunoterapia , Neoplasias Hepáticas/terapia , Sorafenibe/uso terapêutico
19.
Chem Biodivers ; 18(1): e2000733, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33236468

RESUMO

Currently available chemotherapeutic treatments for blood cancers (leukemia) usually have strong side effects. More selective, efficient, and less toxic anticancer agents are needed. We synthesized seven, new, optically pure (12aS)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4],12(2H,11H)-dione derivatives and examined their cytotoxicity towards eight cancer cell lines, including urinary bladder (TCC-SUP, UM-UC-3, KU-19-9), colon (LoVo), and breast (MCF-7, MDA-MB-231) cancer representatives, as well as two leukemic cell lines (MV-4-11, CCRF-CEM) and normal murine fibroblasts (Balb/3T3) as reference cell line. Three of the seven newly-obtained compounds ((12aS)-8-bromo-2-(3-phenylbenzoyl)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4],12(2H,11H)-dione, (12aS)-8,9-dimethoxy-2-(4-phenylbenzoyl)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4],12(2H,11H)-dione and (12aS)-8-nitro-2-(4-phenylbenzoyl)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4],12(2H,11H)-dione, showed enhanced activity and selectivity toward the leukemic MV-4-11 cell lines when compared to our previously reported compounds, with IC50 values in the range of 2.9-5.6 µM. Additionally, (12aS)-9-nitro-2-(4-phenylbenzoyl)-1,3,4,12a-tetrahydropyrazino[2,1-c][1,4],12(2H,11H)-dione exhibited a strong cytotoxic effect against the leukemic CCRF-CEM (IC50 =6.1 µM) and MV-4-11 (IC50 =11.0 µM) cell lines, a moderate cytotoxic effect toward other tumor lines (IC50 =31.8-55.0 µM) and very weak cytotoxic effect toward the Balb/3T3 reference cell lines. Selected compounds were further evaluated for their potential to induce apoptotic cell death in MV-4-11 cells by measuring caspase-3 activity. We also established the crystal structure of three products and investigated the effect of 22 derivatives of 1,3,4,12a-tetrahydropyrazino[2,1-c][1,4],12(2H,11H)-dione on the activity of the cancer-associated enzyme autotaxin. All compounds proved to be weak inhibitors of autotaxin, although some (R) and (S) enantiomers had Ki values of 10-19 µM. The obtained results showed that the tested compounds exhibited a selective antileukemic effect, which appeared not to be related directly to autotaxin. Molecular targets responsible for this effect remain to be identified. The newly obtained compounds can be used in the search for new, selective anticancer therapies.


Assuntos
Antineoplásicos/química , Benzodiazepinas/química , Desenho de Fármacos , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Benzodiazepinas/metabolismo , Benzodiazepinas/farmacologia , Sítios de Ligação , Domínio Catalítico , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Conformação Molecular , Diester Fosfórico Hidrolases/química , Diester Fosfórico Hidrolases/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
20.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 76(Pt 6): 1018-1026, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33289713

RESUMO

A high-resolution single-crystal X-ray diffraction study of abiraterone acetate (1) has been carried out. The charge density distribution in the crystal of this anticancer drug is reconstructed from experimental data. The nature and the contributions of various intermolecular interactions to the total crystal energy are studied by means of the quantum theory `Atoms-in-Molecules', a non-covalent interactions method and energy framework plots. In general, dispersion C-H...H-C and C-H...π interactions play the main role in crystal packing of 1. The Voronoi tessellation analysis of 1 confirmed that contribution of hydrophobic and hydrophilic interactions to the molecular surface is close to their contribution to the total crystal energy. Similar analysis of abiraterone complexes with the cytochrome P450 family demonstrated that contribution of the C-H...H-C and C-H...π interactions to the molecular surface of the drug remains unchanged to fit the binding pocket, despite the presence of water and heme molecules, and hydrophilic groups within the pocket.

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