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1.
Nucleic Acids Res ; 51(D1): D352-D357, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36243982

RESUMEN

Information about the impact of interactions between amyloid proteins on their fibrillization propensity is scattered among many experimental articles and presented in unstructured form. We manually curated information located in almost 200 publications (selected out of 562 initially considered), obtaining details of 883 experimentally studied interactions between 46 amyloid proteins or peptides. We also proposed a novel standardized terminology for the description of amyloid-amyloid interactions, which is included in our database, covering all currently known types of such a cross-talk, including inhibition of fibrillization, cross-seeding and other phenomena. The new approach allows for more specific studies on amyloids and their interactions, by providing very well-defined data. AmyloGraph, an online database presenting information on amyloid-amyloid interactions, is available at (http://AmyloGraph.com/). Its functionalities are also accessible as the R package (https://github.com/KotulskaLab/AmyloGraph). AmyloGraph is the only publicly available repository for experimentally determined amyloid-amyloid interactions.


Asunto(s)
Amiloide , Proteínas Amiloidogénicas , Proteínas Amiloidogénicas/metabolismo , Péptidos , Bases de Datos de Proteínas
2.
Hum Brain Mapp ; 45(1): e26549, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38224538

RESUMEN

The ability to identify and resolve conflicts between standard, well-trained behaviors and behaviors required by the current context is an essential feature of cognitive control. To date, no consensus has been reached on the brain mechanisms involved in exerting such control: while some studies identified diverse patterns of activity across different conflicts, other studies reported common resources across conflict tasks or even across simple tasks devoid of the conflict component. The latter reports attributed the entire activity observed in the presence of conflict to longer time spent on the task (i.e., to the so-called time-on-task effects). Here, we used an extended Multi-Source Interference Task (MSIT) which combines Simon and flanker types of interference to determine shared and conflict-specific mechanisms of conflict resolution in fMRI and their separability from the time-on-task effects. Large portions of the activity in the dorsal attention network and decreases of activity in the default mode network were shared across the tasks and scaled in parallel with increasing reaction times. Importantly, the activity in the sensory and sensorimotor cortices, as well as in the posterior medial frontal cortex (pMFC) - a key region implicated in conflict processing - could not be exhaustively explained by the time-on-task effects.


Asunto(s)
Encéfalo , Conflicto Psicológico , Humanos , Encéfalo/diagnóstico por imagen , Tiempo de Reacción , Lóbulo Frontal , Mapeo Encefálico
3.
Chemistry ; : e202303483, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656538

RESUMEN

Clathrate hydrates are among the most intensively studied H-bond inclusion compounds. Despite the broad definition for this class of compounds, their meaning commonly refers to closed polyhedral nanocages that encapsulate small guest molecules. On the other hand, larger solutes enforce another type of encapsulation because of the solute size effect. Herein, we report a series of structures containing various molecules encapsulated by intercalated water layers constructed of polycyclic moieties of L4(4)8(8) topology. We parametrized the corrugation of individual layers and characterized interactions governing their formation. We suggested that these could be categorized as two-dimensional clathrates based on the character of intra-layer interactions and the effects observed between entrapped molecules and water-based intercalators.

4.
Phys Chem Chem Phys ; 26(21): 15587-15599, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38757742

RESUMEN

Phenol-soluble modulins (PSMs) are extracellular short amphipathic peptides secreted by the bacteria Staphylococcus aureus (S. aureus). They play an essential role in the bacterial lifecycle, biofilm formation, and stabilisation. From the PSM family, PSMα3 has been of special interest recently due to its cytotoxicity and highly stable α-helical conformation, which also remains in its amyloid fibrils. In particular, PSMα3 fibrils were shown to be composed of self-associating "sheets" of α-helices oriented perpendicular to the fibril axis, mimicking the architecture of canonical cross-ß fibrils. Therefore, they were called cross-α-fibrils. PSMα3 was synthesised and verified for identity with wild-type sequences (S. aureus). Then, using several experimental techniques, we evaluated its propensity for in vitro aggregation. According to our findings, synthetic PSMα3 (which lacks the N-terminal formyl groups found in bacteria) does not form amyloid fibrils and maintains α-helical conformation in a soluble monomeric form for several days of incubation. We also evaluated the influence of PSMα3 on human insulin fibrillation in vitro, using a variety of experimental approaches in combination with computational molecular studies. First, it was shown that PSMα3 drastically inhibits the fibrillation of human insulin. The anti-fibrillation effect of PSMα3 was concentration-dependent and required a concentration ratio of PSMα3: insulin equal to or above 1 : 100. Molecular modelling revealed that PSMα3 most likely inhibits the production of insulin primary nuclei by competing for residues involved in its dimerization.


Asunto(s)
Insulina , Agregado de Proteínas , Staphylococcus aureus , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/metabolismo , Humanos , Insulina/metabolismo , Insulina/química , Agregado de Proteínas/efectos de los fármacos , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Amiloide/química , Amiloide/metabolismo
5.
Int J Mol Sci ; 25(9)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38732016

RESUMEN

Enterococcus spp. are normal intestinal tract microflorae found in poultry. However, the last decades have shown that several species, e.g., Enterococcus cecorum, have become emerging pathogens in broilers and may cause numerous losses in flocks. In this study, two combinations (H1 and H2) of menthol, 1,8-cineol, linalool, methyl salicylate, γ-terpinene, p-cymene, trans-anethole, terpinen-4-ol and thymol were used in an in vitro model, analyzing its effectiveness against the strains E. cecorum, E. faecalis, E. faecium, E. hirae and E. gallinarum isolated from broiler chickens from industrial farms. To identify the isolated strains classical microbiological methods and VITEK 2 GP cards were used. Moreover for E. cecorum a PCR test was used.. Antibiotic sensitivity (MIC) tests were performed for all the strains. For the composition H1, the effective dilution for E. cecorum and E. hirae strains was 1:512, and for E. faecalis, E. faecium and E. gallinarum, 1:1024. The second mixture (H2) showed very similar results with an effectiveness at 1:512 for E. cecorum and E. hirae and 1:1024 for E. faecalis, E. faecium and E. gallinarum. The presented results suggest that the proposed composition is effective against selected strains of Enterococcus in an in vitro model, and its effect is comparable to classical antibiotics used to treat this pathogen in poultry. This may suggest that this product may also be effective in vivo and provide effective support in the management of enterococcosis in broiler chickens.


Asunto(s)
Antibacterianos , Pollos , Enterococcus , Pruebas de Sensibilidad Microbiana , Animales , Pollos/microbiología , Enterococcus/efectos de los fármacos , Enterococcus/genética , Enterococcus/aislamiento & purificación , Antibacterianos/farmacología , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/tratamiento farmacológico , Probióticos/farmacología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico
6.
J Struct Biol ; 215(3): 108002, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37482232

RESUMEN

Repetitivity and modularity of proteins are two related notions incorporated into multiple evolutionary concepts. We discuss whether they may also be essential for functional amyloids. Amyloids are proteins that create very regular and usually highly insoluble fibrils, which are often associated with neurodegeneration. However, recent discoveries showed that amyloid structure of a protein could also be beneficial and desired, e.g., to promote cell adhesion. Functional amyloids are proteins which differ in their characteristics from pathological amyloids, so that the fibril formation could be more under control of an organism. We propose that repeats in the sequence could regulate the aggregation propensity of these proteins. The inclusion of multiple symmetric interactions, due to the presence of the repeats, could be supporting and strengthening the desirable structural properties of functional amyloids. Our results show that tandem repeats in bacterial functional amyloids have a distinct characteristic. The pattern of repeats supports the appropriate level of fibril formation and better controllability of fibril stability. The repeats tend to be more imperfect, which attenuates excessive aggregation propensity. Their desired structure and function are also reinforced by their amino acid profile. Although in the study we focused on bacterial functional amyloids, due to their importance in biofilm formation, we propose that similar mechanisms could be employed in other functional amyloids which are designed by evolution to aggregate in a desirable manner, but not necessarily in pathological amyloids.


Asunto(s)
Amiloide , Proteínas Bacterianas , Proteínas Bacterianas/química , Amiloide/química , Secuencia de Aminoácidos , Secuencias Repetitivas de Aminoácido , Agregado de Proteínas , Biopelículas
7.
PLoS Comput Biol ; 18(12): e1010787, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36542665

RESUMEN

NLR proteins are intracellular receptors constituting a conserved component of the innate immune system of cellular organisms. In fungi, NLRs are characterized by high diversity of architectures and presence of amyloid signaling. Here, we explore the diverse world of effector and signaling domains of fungal NLRs using state-of-the-art bioinformatic methods including MMseqs2 for fast clustering, probabilistic context-free grammars for sequence analysis, and AlphaFold2 deep neural networks for structure prediction. In addition to substantially improving the overall annotation, especially in basidiomycetes, the study identifies novel domains and reveals the structural similarity of MLKL-related HeLo- and Goodbye-like domains forming the most abundant superfamily of fungal NLR effectors. Moreover, compared to previous studies, we found several times more amyloid motif instances, including novel families, and validated aggregating and prion-forming properties of the most abundant of them in vitro and in vivo. Also, through an extensive in silico search, the NLR-associated amyloid signaling was identified in basidiomycetes. The emerging picture highlights similarities and differences in the NLR architectures and amyloid signaling in ascomycetes, basidiomycetes and other branches of life.


Asunto(s)
Amiloide , Proteínas Fúngicas , Proteínas Fúngicas/metabolismo , Amiloide/química , Proteínas Amiloidogénicas , Proteínas NLR/metabolismo
8.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35806175

RESUMEN

Short peptides have great potential as safe and effective anticancer drug leads. Herein, the influence of short cyclic peptides containing the Pro-Pro-Phe-Phe sequence on patient-derived melanoma cells was investigated. Cyclic peptides such as cyclo(Leu-Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe-), called CLA, and cyclo(Pro-homoPro-ß3homoPhe-Phe-), called P11, exert the cytotoxic and the cytostatic effects in melanoma cells, respectively. CLA was the most active peptide as it reduced the viability of melanoma cells to 50% of control at about 10 µM, whereas P11 at about 40 µM after 48 h incubation. Interestingly, a linear derivative of P11 did not induce any effect in melanoma cells confirming previous studies showing that cyclic peptides exert better biological activity compared to their linear counterparts. According to in silico predictions, cyclic tetrapeptides show a better pharmacokinetic and toxic profile to humans than CLA. Notably, the spatial structure of those peptides containing synthetic amino acids has not been explored yet. In the Cambridge Structural Database, there is only one such cyclic tetrapeptide, cyclo((R)-ß2homoPhe-D-Pro-Lys-Phe-), while in the Protein Data Bank-none. Therefore, we report the first crystal structure of cyclo(Pro-Pro-ß3homoPhe-Phe-), denoted as 4B8M, a close analog of P11, which is crucial for drug discovery. Comparative molecular and supramolecular analysis of both structures was performed. The DFT findings revealed that 4B8M is well interpreted in the water solution. The results of complex Hirshfeld surface investigations on the cooperativity of interatomic contacts in terms of electrostatic and energetic features are provided. In short, the enrichment ratio revealed O…H/H…O and C…H/H…C as privileged intercontacts in the crystals in relation to basic and large supramolecular H-bonding synthon patterns. Furthermore, the ability of self-assemble 4B8M leading to a nanotubular structure is also discussed.


Asunto(s)
Melanoma , Péptidos Cíclicos , Dipéptidos , Humanos , Melanoma/tratamiento farmacológico , Péptidos , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología
9.
Int J Mol Sci ; 22(10)2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-34066237

RESUMEN

CsgA is an aggregating protein from bacterial biofilms, representing a class of functional amyloids. Its amyloid propensity is defined by five fragments (R1-R5) of the sequence, representing non-perfect repeats. Gate-keeper amino acid residues, specific to each fragment, define the fragment's propensity for self-aggregation and aggregating characteristics of the whole protein. We study the self-aggregation and secondary structures of the repeat fragments of Salmonella enterica and Escherichia coli and comparatively analyze their potential effects on these proteins in a bacterial biofilm. Using bioinformatics predictors, ATR-FTIR and FT-Raman spectroscopy techniques, circular dichroism, and transmission electron microscopy, we confirmed self-aggregation of R1, R3, R5 fragments, as previously reported for Escherichia coli, however, with different temporal characteristics for each species. We also observed aggregation propensities of R4 fragment of Salmonella enterica that is different than that of Escherichia coli. Our studies showed that amyloid structures of CsgA repeats are more easily formed and more durable in Salmonella enterica than those in Escherichia coli.


Asunto(s)
Amiloide/química , Proteínas Bacterianas/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Salmonella enterica/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Proteínas de Escherichia coli/genética , Agregado de Proteínas , Conformación Proteica , Salmonella enterica/genética , Salmonella enterica/crecimiento & desarrollo , Homología de Secuencia
10.
Inorg Chem ; 59(7): 4340-4348, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-32133839

RESUMEN

We report on the synthesis and structural characterization of two series of lanthanide-containing 22-tungsto-2-germanates. The first series corresponds to a family of polyanions with the formula [Ln(ß2-GeW11O39)2]13- (LnIII = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Gd (6), Dy (7)), and the second series corresponds to a family with the formula [Ln(ß2-GeW11O39)(α-GeW11O39)]13- (LnIII = Ho (8), Er (9), Tm (10)). All compounds were characterized in the solid state by single-crystal and powder XRD, IR, TGA, and SQUID magnetometry. The polyanions were synthesized in aqueous medium by direct reaction of the monolacunary [ß2-GeW11O39]8- POM precursor with the corresponding lanthanide salts. The structure of the polyanions consists of an 8-coordinated lanthanide ion in a square-antiprismatic geometry, which is sandwiched either between two [ß2-GeW11O39]8- units for 1-7 or between a [ß2-GeW11O39]8- and a [α-GeW11O39]8- unit for 8-10. Furthermore, the effect of the central paramagnetic lanthanide ion on the magnetic behavior of the polyanions was investigated, with the erbium-derivative [Er(ß2-GeW11O39)(α-GeW11O39)]13- (9) showing single-molecule magnet (SMM) behavior.

11.
Chemistry ; 25(10): 2616-2630, 2019 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-30560574

RESUMEN

Two series of 1,12-bis-zwitterionic derivatives of the [closo-B12 H12 ]2- anion (B), containing either two 4-alkoxypyridinium groups (1B[n]-p) or one 4-alkoxypyridinium and one 4-pentylthianium groups (2B[n]-p), were prepared and their structural (XRD, DFT), thermal, and photophysical properties were compared with those of the analogous derivatives of the [closo-B10 H10 ]2- anion (1A[n]-p and 2A[n]-p). Some 1,7-derivatives of B were isolated and investigated. Both series 1[n] and 2[n] exhibit nematic and crystalline polymorphism; the 12-vertex derivatives (B) have higher transition temperatures than those of the 10-vertex analogues (A). All compounds fluoresce with quantum yields higher for 1B (ΦF =0.37 for 1B[7]-p and ΦF =0.27 for 2B[7]-p) than those for the 10-vertex analogues (ΦF =0.04 for 2A[5]-p). DFT calculations demonstrate an order of magnitude lower first hyperpolarizability, ß(-ω,ω,0) , for 2B[7]-p than that for the 10-vertex analogue 2A[7]-p (1.7×10-30 vs. 18.9×10-30  esu at ω=0).

12.
Nucleic Acids Res ; 45(4): 2137-2149, 2017 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-27913732

RESUMEN

N6-Threonylcarbamoyladenosine (t6A) and its derivatives are universally conserved modified nucleosides found at position 37, 3΄ adjacent to the anticodon in tRNAs responsible for ANN codons. These modifications have pleiotropic functions of tRNAs in decoding and protein synthesis. In certain species of bacteria, fungi, plants and protists, t6A is further modified to the cyclic t6A (ct6A) via dehydration catalyzed by TcdA. This additional modification is involved in efficient decoding of tRNALys. Previous work indicated that the chemical structure of ct6A is a cyclic active ester with an oxazolone ring. In this study, we solved the crystal structure of chemically synthesized ct6A nucleoside. Unexpectedly, we found that the ct6A adopted a hydantoin isoform rather than an oxazolone isoform, and further showed that the hydantoin isoform of ct6A was actually present in Escherichia coli tRNAs. In addition, we observed that hydantoin ct6A is susceptible to epimerization under mild alkaline conditions, warning us to avoid conventional deacylation of tRNAs. A hallmark structural feature of this isoform is the twisted arrangement of the hydantoin and adenine rings. Functional roles of ct6A37 in tRNAs should be reconsidered.


Asunto(s)
Adenosina/análogos & derivados , Hidantoínas/química , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Adenosina/síntesis química , Adenosina/química , Adenosina/metabolismo , Escherichia coli/genética , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular , Conformación de Ácido Nucleico , ARN Bacteriano/química , ARN Bacteriano/metabolismo
13.
Molecules ; 24(18)2019 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-31527447

RESUMEN

To successfully design and optimize the application of hydrogel matrices one has to effectively combine computational design tools with experimental methods. In this context, one of the most promising techniques is molecular modeling, which requires however accurate molecular models representing the investigated material. Although this method has been successfully used over the years for predicting the properties of polymers, its application to biopolymers, including gelatin, is limited. In this paper we provide a method for creating an atomistic representation of gelatin based on the modified FASTA codes of natural collagen. We show that the model created in this manner reproduces known experimental values of gelatin properties like density, glass-rubber transition temperature, WAXS profile and isobaric thermal expansion coefficient. We also present that molecular dynamics using the INTERFACE force field provides enough accuracy to track changes of density, fractional free volume and Hansen solubility coefficient over a narrow temperature regime (273-318 K) with 1 K accuracy. Thus we depict that using molecular dynamics one can predict properties of gelatin biopolymer as an efficient matrix for immobilization of various bioactive compounds, including enzymes.


Asunto(s)
Gelatina/química , Modelos Moleculares , Conformación Proteica , Algoritmos , Secuencia de Aminoácidos , Análisis de Varianza , Biopolímeros/química , Hidrogeles/química , Temperatura
14.
Molecules ; 24(16)2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31412581

RESUMEN

The crystal structure of the new polymorphic form of 3-aminoflavone (3-AF) has been determined by single crystal X-ray diffraction. This report presents results of fluorimetric studies on 3-AF in methanol and aquatic solvents. Based on 3D fluorescence emission spectra, optimal values for excitation (λex) and emission/analytical (λem) wavelength, the analytical concentration range as well as the range of concentration quenching for the studied compound were established. Moreover, the limit of detection (LOD) and the limit of quantification (LOQ) were determined. The results were compared with those obtained using the standard UV-Vis absorption spectrophotometric method. The effect of acidity (pH) and the concentration of halide anions (chlorides, bromides, iodides and fluorides) on fluorescence quenching were analysed.


Asunto(s)
Flavonoides/química , Fluorescencia , Modelos Moleculares , Cristalografía por Rayos X , Fluorometría , Límite de Detección , Metanol/química , Conformación Molecular , Estructura Molecular , Solventes/química , Espectrofotometría , Agua/química
15.
Neurol Neurochir Pol ; 53(1): 34-42, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30628049

RESUMEN

AIM OF THE STUDY: Intraventricular meningiomas (IVMs) are rare tumours accounting for 0.5-3.0% of all meningiomas. IVMs require different surgical approaches and preparation in deep brain areas. The aim of our study was to present the clinico- -histopathological characteristics and treatment outcomes of trigone IVMs in a series of 15 patients. MATERIALS AND METHODS: Eight women and seven men (mean age 52) with 15 trigone IVMs were retrospectively analysed. Patients presented with headache (47%), psychoorganic syndrome (40%), hemianopsia (33%) or paresis (20%), including three (20%) patients with Karnofsky Performance Scale (KPS) < 80. Mean tumour size was 55.2 mm (range: 30-100 mm). RESULTS: Gross total tumour resection was performed in 14 (93%) cases, and subtotal in one (7%). A new deficit appeared in 83% (5/6) following a transparietal approach, in 14% (1/7) following a transtemporal approach, and in none of two patients following a transoccipital approach. Postoperative complications occurred in six (40%) patients; no patient died, but in two (13%) the new deficit was permanent. Tumour re-growth was found in two (13%) patients after 14 and 31 months. Meningiomas of WHO grade I occurred in 12, grade II in three, and grade III in one tumour recurrence. In long-term follow-up (mean: 60.8 months), including the results of revision operations, KPS: 80-100 was in 13 (87%) patients, KPS: 50 in one (severe hemiparesis after revision) and one patient was lost to follow-up (KPS: 100 on discharge). CONCLUSIONS: 20% of IVMs in our series were atypical. The results of surgery for IVMs, although satisfactory in general, require further improvement by reducing the rate of focal deficits resulting from a surgical approach.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Resultado del Tratamiento
16.
Chem Biodivers ; 15(9): e1800242, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29935105

RESUMEN

An efficient synthetic strategy to 3-methylidene-2,3-dihydroquinolin-4(1H)-ones variously substituted in position 2 has been developed. The title compounds were synthesized in the reaction sequence involving reaction of diethyl methylphosphonate with methyl 2-(tosylamino)benzoate, condensation of thus formed diethyl 2-oxo-2-(2-N-tosylphenyl)ethylphosphonate with various aldehydes followed by successful application of the obtained 3-(diethoxyphosphoryl)-1,2-dihydroquinolin-4-ols as Horner-Wadsworth-Emmons reagents for the olefination of formaldehyde. Also, enantioselective approach to the target compounds has been evaluated using 3-dimenthoxyphosphoryl group as a chiral auxiliary. Single X-ray crystal analysis of (2S)-3-(dimenthoxyphosphoryl)-2-phenyl-1-tosyldihydroquinolin-4-ol revealed the presence of strong resonance-assisted hydrogen bond (RAHB). The obtained 3-methylidene-2,3-dihydroquinolin-4(1H)-ones were then tested for their cytotoxic activity against two leukemia cell lines NALM-6 and HL-60 and a breast cancer MCF-7 cell line. All compounds showed very high cytotoxic activity with the IC50 values mostly below 1 µm in all three cancer cell lines. The selected analogs were also tested on human umbilical vein endothelial cells (HUVEC) and on human mammary gland/breast cells (MCF-10A) to evaluate their influence on normal cells. Since one of the most serious problems in cancer chemotherapy is the development of drug resistance, the mRNA levels and activity of ABCB1 transporter considered to be the most important factor engaged in drug resistance, were evaluated in MCF-7 cells treated with two selected analogs. Both compounds were strong ABCB1 transporter inhibitors that could prevent efflux of anticancer drugs from cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Quinolinas/síntesis química , Quinolinas/farmacología , Compuestos de Tosilo/síntesis química , Compuestos de Tosilo/farmacología , Subfamilia B de Transportador de Casetes de Unión a ATP/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Modelos Moleculares , Estructura Molecular , Quinolinas/química , Relación Estructura-Actividad , Compuestos de Tosilo/química
17.
Neurol Neurochir Pol ; 51(6): 446-453, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28826919

RESUMEN

BACKGROUND AND PURPOSE: Spinal dural arteriovenous fistulas (SDAVFs) are rare, acquired pathology and they inevitably lead to severe disability if untreated. The aim of this study is to present the outcome and complications, and to find factors that may affect the outcome after surgical treatment. METHODS: Seventeen consecutive patients (men - 14, women - 3, age: 41-79) were retrospectively analyzed. The patients presented with paraparesis (88%), bladder symptoms (71%) and/or sensory disturbances (65%). The fistula was found in the upper thoracic spine in 2 cases, in the lower thoracic (T7-Th12) in 11 cases, and in the lumbar spine in 4 cases. Microsurgical shunt interruption was performed in all, followed by epidural arteries coagulation in 12 cases. RESULTS: In the long term, improvement or achievement of a good stable condition was observed in 13 patients (76%), and no patient deteriorated. All 5 paraplegic patients improved by at least 1 grade in MCS. Satisfactory results (modified McCormick Scale grades I-II) were found in 10 patients (59%), and 15(88%) were independent. Postoperative complications occurred in 4 patients (24%), two of them (12%) required revision surgery for epidural hematoma. The success rate was 94%; one patient required revision surgery for recurrent SDAVF. Better neurological condition on admission (p=0.0098) and age >60 years (p=0.0498) were the factors associated with satisfactory outcome. CONCLUSIONS: Microsurgical closing of a SDAVF brings good and stable results over time. Aggressive treatment should be attempted even in cases of total loss of spinal cord function. Neurological condition before surgery and age may influence the outcome.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Complicaciones Posoperatorias , Procedimientos Quirúrgicos Vasculares/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Microcirugia/efectos adversos , Microcirugia/métodos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos
18.
Neurol Neurochir Pol ; 50(2): 75-82, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26969562

RESUMEN

OBJECTIVE: To report clinical characteristics, treatment outcomes and risk of recurrence in patients with surgically treated cerebellopontine angle epidermoids. METHODS: In 1994-2013, we operated 17 patients, including 7 with tumor limited to the cerebellopontine angle, 7 with cerebellopontine angle tumor penetrating supratentorially, and 3 with cerebellopontine angle tumor extending along skull base to contralateral cerebellopontine angle. All patients were followed-up for the mean duration of 126 months. RESULTS: On admission cranial nerve symptoms predominated. Total tumor removal was achieved in 5 patients, and incomplete removal (with small tumor remnants left on vessels, nerves, or brainstem) in 12 patients. Postoperatively, preoperative deficits worsened in 2 and new postoperative deficits occurred in 10 patients. The extent of tumor expansion had no effect on postoperative morbidity and risk of recurrence. During long-term follow-up, improvement or resolution of preoperative deficits was seen in 11 of 17 patients, and new postoperative deficits in 8 of 10 patients. Symptomatic recurrences after an average of more than 9 years were noted in 5 patients, 3 of whom were reoperated. Recurrences occurred in some younger patients and always in area of primary tumor. No effect of extent of tumor removal on risk of recurrence was found. CONCLUSIONS: The extent of tumor removal had no effect on the risk of recurrence, and thus it may be acceptable to leave tumor capsule fragments adhering closely to nerves, vessels, or brainstem. During long-term follow-up, resolution or improvement of present preoperatively and new postoperative neurological deficits may be expected in most patients.


Asunto(s)
Neoplasias Cerebelosas/patología , Ángulo Pontocerebeloso/patología , Quiste Epidérmico/patología , Recurrencia Local de Neoplasia/patología , Evaluación de Resultado en la Atención de Salud , Adolescente , Adulto , Neoplasias Cerebelosas/cirugía , Ángulo Pontocerebeloso/cirugía , Quiste Epidérmico/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/cirugía , Adulto Joven
19.
Childs Nerv Syst ; 31(7): 1025-31, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25771924

RESUMEN

BACKGROUND: Hypertrophic pachymeningitis (HP) is a rare clinical entity characterized by diffuse or localized fibrous thickening of the dura mater. It is well known but rare especially in pediatric population disease of differing origins. The primary (idiopathic) form is diagnosed after excluding other possible etiologies. Similar results from magnetic resonance imaging (MRI) for patients with hypertrophic pachymeningitis and meningiomas may make the diagnosis confusing. Additionally, making a proper diagnosis without histological sampling can be difficult in some cases. CASE DESCRIPTION: We present a case of an 18-year-old boy diagnosed with hypertrophic pachymeningitis in the area of the hypoglossal canal. The diagnosis was made after a 2-month history of hypoglossal nerve palsy and dysphagia preceded by a middle ear infection. The patient was treated surgically with suspicion of meningioma, but no evidence of a tumor was found during the operation. The postoperative period was uneventful. At the latest check-up, MRI revealed regression of all previously observed pathological changes.


Asunto(s)
Duramadre/patología , Meningitis/patología , Meningitis/cirugía , Adolescente , Humanos , Hipertrofia , Imagen por Resonancia Magnética , Masculino
20.
Chempluschem ; 89(5): e202300734, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38216541

RESUMEN

Four alkaline earth metal complexes of ketoprofen (Hket) and indomethacin (Hind) were synthesized and characterized: [Ca(ket)2(H2O)2]n (1), [Mg(ket)2(H2O)2] (2), [Ca(ind)2(EtOH)2]n (3), and [Mg(ind)2(EtOH)2] (4). All compounds were studied by elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Crystal structures of 1 and 3 were determined by single crystal X-ray diffraction technique T=100 K. The structure of 1 is dominated by a one-dimensional coordination polymer, while 3 is formed by a two-dimensional layer stabilized by the calcium zig-zag chains and π⋅⋅⋅π stacking interactions. Crystal packing arrangements were characterized by fingerprint plots (FPs) that were derived from the Hirshfeld surfaces (HSs). The antioxidant and antimicrobial activities of complexes were evaluated against Gram-positive and Gram-negative bacteria as well as yeasts.


Asunto(s)
Antiinflamatorios no Esteroideos , Antioxidantes , Complejos de Coordinación , Pruebas de Sensibilidad Microbiana , Polímeros , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/síntesis química , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/síntesis química , Cristalografía por Rayos X , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Polímeros/química , Polímeros/síntesis química , Polímeros/farmacología , Calcio/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Modelos Moleculares , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antiinfecciosos/síntesis química , Indometacina/farmacología , Indometacina/química
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