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1.
J Org Chem ; 89(10): 6937-6950, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38691817

RESUMEN

Domino Knoevenagel-cyclization reactions of N-arylcinnamylamines were carried out with active methylene reagents, which took place with five competing cyclization mechanisms: intramolecular hetero Diels-Alder reaction, stepwise polar [2 + 2] cycloaddition, styryl or aza-Diels-Alder reactions followed by rearomatization, and [1,5]-hydride shift-6-endo cyclization. In the stepwise aza-Diels-Alder reaction, the N-vinylpyridinium moiety acted as an azadiene, producing a condensed heterocycle with tetrahydroquinolizinium and tetrahydroquiniline subunits. Antiproliferative activity with low micromolar IC50 values was identified for some of the novel scaffolds.

2.
Plants (Basel) ; 12(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38140443

RESUMEN

The carotenoid composition of the flower of Telekia speciosa was investigated for the first time by HPLC-DAD-MS. In addition to the main carotenoid lutein and its geometrical isomers, 5,6-epoxy-carotenoids, namely violaxanthin, lutein 5,6-epoxide and antheraxanthin, were detected in larger amounts. In addition, ß-carotene 5,6-epoxide and ß-carotene 5,6,5',6'-diepoxide were found, which occurs very rarely in plants. For unambigous identification, ß-carotene 5,6-epoxide and ß-carotene 5,6,5',6'-diepoxide were prepared semisynthetically, and they were characterized by 1H and 13C NMR and HPLC-CD methods.

3.
J Agric Food Chem ; 71(29): 11056-11068, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37436951

RESUMEN

Clonostachys rosea is a fungus widely distributed on Earth and has a high capacity to adapt to complex environments in soil, plants, or sea. It is an endophyte that can be used as a potential biocontrol agent to protect plants from pathogenic fungi, nematodes, and insects. However, the spectrum of secondary metabolites produced by C. rosea has only scarcely been studied. In the present study, eight new phenalenones, asperphenalenones F-M (1-8), together with two known derivatives, asperphenalenones E and B (9 and 10), were isolated from the axenic rice culture of this fungus. The structures of the new compounds were elucidated by nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism, and gas chromatography-mass spectrometry analyses. Asperphenalenones J-M (5-8) are unusual phenalenone adducts that are conjugated to diterpenoid glycosides. Asperphenalenones F and H showed moderate antibacterial activity against methicillin-resistant Staphylococcus aureus, with minimal inhibitory concentrations of 12.5 and 25 µM, respectively. Asperphenalenone B exhibited low antiviral activity against the human immunodeficiency virus replication. Furthermore, asperphenalenones F and H exhibited low cytotoxicity against Jurkat cells, while all other compounds were devoid of cytotoxicity.


Asunto(s)
Antiinfecciosos , Hypocreales , Staphylococcus aureus Resistente a Meticilina , Nematodos , Animales , Humanos , Hypocreales/metabolismo , Antiinfecciosos/farmacología , Antiinfecciosos/metabolismo
4.
Pharmaceutics ; 13(12)2021 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-34959370

RESUMEN

Seven new germacranolides (1-3, 5-8), among them a heterodimer (7), and known germacranolide (4), eudesmane (9) and isodaucane (10) sesquiterpenes were isolated from the aerial parts of Neurolaena lobata. Their structures were determined by using a combination of different spectroscopic methods, including HR-ESIMS and 1D and 2D NMR techniques supported by DFT-NMR calculations. The enantiomeric purity of the new compounds was investigated by chiral HPLC analysis, while their absolute configurations were determined by TDDFT-ECD and OR calculations. Due to the conformationally flexible macrocycles and difficulties in assigning the relative configuration, 13C and 1H NMR chemical shift and ECD and OR calculations were performed on several stereoisomers of two derivatives. The isolated compounds (1-10) were shown to have noteworthy antiproliferative activities against three human cervical tumor cell line with different HPV status (HeLa, SiHa and C33A). Additionally, lobatolide C (6) exhibited substantial antiproliferative properties, antimigratory effect, and it induced cell cycle disturbance in SiHa cells.

5.
Molecules ; 26(20)2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34684696

RESUMEN

Efficient Lewis-acid-catalyzed direct conversion of aldehydes to 1,2-diketones in the liquid phase was enabled by using newly designed and developed ceria-zirconia-based high-entropy oxides (HEOs) as the actual catalysts. The synergistic effect of various cations incorporated in the same oxide structure (framework) was partially responsible for the efficiency of multicationic materials compared to the corresponding single-cation oxide forms. Furthermore, a clear, linear relationship between the Lewis acidity and the catalytic activity of the HEOs was observed. Due to the developed strategy, exclusively diketone-selective, recyclable, versatile heterogeneous catalytic transformation of aldehydes can be realized under mild reaction conditions.

6.
Orv Hetil ; 162(22): 861-869, 2021 05 30.
Artículo en Húngaro | MEDLINE | ID: mdl-34052800

RESUMEN

Összefoglaló. Bevezetés és célkituzés: A 3 év alatti korcsoportban a súlyos kisgyermekkori fogszuvasodás (S-ECC) gyakoriságának vizsgálata és a kisgyermekes szülok szájegészséggel kapcsolatos ismereteinek felmérése. Módszer: Háromszázhatvankét, 36 hónapos vagy annál fiatalabb gyermek (átlagéletkor: 28,49 ± 5,25 hónap) fogászati szurovizsgálatát végeztük el, és szüleik számára önkéntesen kitöltheto kérdoívet állítottunk össze. A 306 kitöltött kérdoív eredményét a gyermekek fogászati statusával egyénenként összevetve statisztikai analízist végeztünk. Eredmények: A gyermekek fogászati szurésekor 15,46% volt a cariesprevalencia: df-t-index = 0,685 ± 2,20; az általunk javasolt, az elotört fogak számával módosított df-t-index = 0,758 ± 2,42, SiC-index = 2,06 ± 3,33. A vizsgált populációban nem találtunk tömött vagy fogszuvasodás miatt eltávolított fogat. A korábban szájhigiénés tájékoztatásban részesült/nem részesült szülok gyermekeinél nem volt szignifikáns különbség a szuvas fogak számának (p = 0,196), a fogyasztott folyadék cukortartalmának (81,5%/71,5%) és a bevitel módjának (p = 0,453) tekintetében. A gyermeküket 6 hónapos korukig kizárólagosan anyatejjel tápláló édesanyák nagyobb eséllyel választották a vízzel történo itatást (75%/52%) pohárból (68,1%/28,8%) a késobbiekben. Az édesanya legmagasabb iskolai végzettsége kulcsszerepet játszik mind az anyatejes táplálás melletti elhivatottságban (felsofok: 53,4%, középfok: 34,2%, alapfok: 37,5%), mind a cariesfrekvencia csökkentésében (p = 0,015). Következtetés: A szüloi szájhigiénés prevenciós tájékoztatás jelenleg nem hatékony. Eredményeink alapján a fogászati szurést 1 éves kor elott meg kell kezdeni, amely a hatékony, rendszeres fogászati prevenciós tanácsadás lehetoségét is megteremtené. Szükségesnek látjuk a védonok és a gyermekháziorvosok folyamatos továbbképzésében a kisgyermekkori fogszuvasodás alapismereteinek integrációját. Orv Hetil. 2021; 162(22): 861-869. INTRODUCTION AND OBJECTIVE: To investigate the frequency of severe early childhood caries (S-ECC) under 3 years of age and to assess the oral health related knowledge of parents/guardians with preschool children. METHOD: 362 children younger than 36 months (mean age: 28.49 ± 5.25 months) were screened and a voluntary questionnaire for their parents was compiled. Statistical analysis was carried out comparing the results of the 306 completed questionnaires with the dental status of the screened children. RESULTS: Caries prevalence in the examined population was 15.46%, df-t index = 0.685 ± 2.20, our suggested modified df-t index based on the number of erupted teeth = 0.758 ± 2.42, SiC-index = 2.06 ± 3.33. No filled or extracted tooth due to caries was found in the study group. There was no significant difference in the number of carious teeth (p = 0.196), consumption of sugar-containing drinks (81.5%/71.5%) and administration of drinks (p = 0.453) in the case of children whose parents had previously received/not received oral hygiene information. Mothers who exclusively breastfed until the age of 6 months were more likely to choose to offer water (75%/52%) from cup (68.1%/28.8%) later. The mother's highest level of education plays a key role in both the commitment to breastfeeding (tertiary: 53.4%, secondary: 34.2%, primary: 37.5%) and in reducing the incidence of caries (p = 0.015). CONCLUSION: Parental oral hygiene preventive instruction is currently ineffective. Based on our results, dental screening should be started before the age of 1 year, that would also provide an opportunity of effective, regular dental prevention counseling. There is a need for the integration of the basics of early childhood caries in the continuous professional training of district nurses and pediatricians. Orv Hetil. 2021; 162(22): 861-869.


Asunto(s)
Susceptibilidad a Caries Dentarias , Madres , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Prevalencia , Encuestas y Cuestionarios
7.
Sci Rep ; 11(1): 6188, 2021 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-33731734

RESUMEN

This study primarily focuses on the assessment of dentistry students' improvement of manual skills resulting from their participation in courses. We aimed to prove that systematic manual skills development significantly improves dexterity. We hypothesized that the dexterity training regimen improves manual dexterity demonstrated by the HAM-Man (Hamburg Assessment Test for Medicine-Manual Dexterity) test scores and CGM (cerebellar grey matter) growth. Thirty volunteers were randomly divided into two equal groups (study and control). Firstly, volunteers were examined by the HAM-Man test and baseline MRI scans. Afterwards, a manual skills development course was launched for the "study group". Secondly, all the manual skills of the students were evaluated longitudinally, by the HAM-Man test. Simultaneously, the follow-up MRI scans were taken to observe morphologic changes in the cerebellum. The Wilcoxon signed-rank test and Student Paired t-test were used for statistical analyses. Value p < 0.05 was considered significant. After the training, significant growth of CGM as well as improvement on manual skill assessment tests, were found in the study group. Training courses are suitable for preparing students with low levels of dexterity for performing demanding tasks. The improvement is demonstrable by a wire bending test and by bilateral CGM enlargement as well.


Asunto(s)
Odontología , Sustancia Gris/fisiología , Destreza Motora , Desempeño Psicomotor , Adolescente , Adulto , Competencia Clínica , Femenino , Humanos , Estudios Longitudinales , Masculino , Estudiantes , Adulto Joven
8.
Ideggyogy Sz ; 73(7-08): 255-259, 2020 Jul 30.
Artículo en Húngaro | MEDLINE | ID: mdl-32750242

RESUMEN

The evaluation of hand dexterity is an important marker for the success of DBS (deep brain stimulation) operation in patients with Parkinson's disease. In this study we applied a simple, semiquantitative optical dental plaque staining technique for the evaluation of the hand dexterity. Ten patient with Parkinson's disease were involved in the study. After dental students aided tooth brushing, bacterial dental deposits (plaque) were stained then photographed, and quantified under standard conditions before and after DBS surgery. Our results showed a significant decrease in dental plaque deposits after DBS operation. This simple technique seems to be a routinely applicable marker for the evaluation of the hand dexterity. Our future plans is repeating the previous experiement on a higher number of cases.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Enfermedad de Parkinson/fisiopatología , Cepillado Dental , Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Destreza Motora , Higiene Bucal , Resultado del Tratamiento
9.
Chirality ; 32(5): 579-587, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32126590

RESUMEN

Two new carotenoids, sapotexanthin 5,6-epoxide and sapotexanthin 5,8-epoxide, have been isolated from the ripe fruits of red mamey (Pouteria sapota). Sapotexanthin 5,6-epoxide was also prepared by partial synthesis via epoxidation of sapotexanthin, and the (5R,6S) and (5S,6R) stereoisomers were identified by high-performance liquid chromatography-electronic circular dichroism (HPLC-ECD) analysis. Spectroscopic data of the natural and semisynthetic derivatives obtained by acid-catalyzed rearrangement of cryptocapsin 5,8-epoxide stereoisomers were compared for structural elucidation.


Asunto(s)
Carotenoides/análisis , Carotenoides/aislamiento & purificación , Compuestos Epoxi/química , Pouteria/química , Carotenoides/química , Estereoisomerismo
10.
Chirality ; 32(5): 605-610, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32115775

RESUMEN

The endophytic fungus Coniothyrium sp. was isolated from leaves of Quercus robur. Fermentation of this fungus on solid rice medium yielded two new furoic acid derivatives (1 and 2) and two additional known compounds. The structures of the new compounds were determined by extensive analysis of 1D and 2D nuclear magnetic resonance spectra as well as high-resolution mass spectrometry data. Compound 1, containing three aromatic chromophores attached by rotatable sigma bonds and a chirality center in benzylic position, was found to be a scalemic mixture with an excess of the (S) enantiomer, the absolute configuration of which was elucidated as by the solution time-dependent density functional theory-electronic circular dichroism approach. The ωB97X/TZVP PCM/MeCN and SOGGA11-X/TZVP SMD/MeCN methods were used for geometry reoptimization to reproduce the solution conformational ensemble. All isolated compounds were tested for their cytotoxicity but proved to be inactive.


Asunto(s)
Antineoplásicos/química , Ascomicetos/química , Furanos/química , Animales , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Línea Celular Tumoral , Furanos/aislamiento & purificación , Furanos/farmacología , Ratones , Modelos Moleculares , Conformación Molecular , Estereoisomerismo
11.
Molecules ; 25(3)2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32024181

RESUMEN

Flavonoids and carotenoids possess beneficial physiological effects, such as high antioxidant capacity, anticarcinogenic, immunomodulatory, and anti-inflammatory properties, as well as protective effects against UV light. The covalent coupling of hydrophobic carotenoids with hydrophilic flavonoids, such as daidzein and chrysin, was achieved, resulting in new amphipathic structures. 7-Azidohexyl ethers of daidzein and chrysin were prepared in five steps, and their azide-alkyne [4 + 2] cycloaddition with pentynoates of 8'-apo-ß-carotenol, zeaxanthin, and capsanthin afforded carotenoid-flavonoid conjugates. The trolox-equivalent antioxidant capacity against ABTS•+ radical cation and self-assembly of the final products were examined. The 1:1 flavonoid-carotenoid hybrids generally showed higher antioxidant activity than their parent flavonoids but lower than that of the corresponding carotenoids. The diflavonoid hybrids of zeaxanthin and capsanthin, however, were found to exhibit a synergistic enhancement in antioxidant capacities. ECD (electronic circular dichroism) and UV-vis analysis of zeaxanthin-flavonoid conjugates revealed that they form different optically active J-aggregates in acetone/water and tetrahydrofuran/water mixtures depending on the solvent ratio and type of the applied aprotic polar solvent, while the capsanthin derivatives showed no self-assembly. The zeaxanthin bis-triazole conjugates with daidzein and with chrysin, differing only in the position of a phenolic hydroxyl group, showed significantly different aggregation profile upon the addition of water.


Asunto(s)
Antioxidantes/química , Carotenoides/química , Técnicas de Química Sintética , Flavonoides/química , Análisis de Varianza , Antioxidantes/síntesis química , Estructura Molecular , Análisis Espectral
12.
J Med Chem ; 62(13): 6116-6136, 2019 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-31251604

RESUMEN

Epimeric series of aryl-substituted glucopyranosylidene-spiro-imidazolinones, an unprecedented new ring system, were synthesized from the corresponding Schiff bases of O-perbenzoylated (gluculopyranosylamine)onamides by intramolecular ring closure of the aldimine moieties with the carboxamide group elicited by N-bromosuccinimide in pyridine. Test compounds were obtained by Zemplén O-debenzoylation. Stereochemistry and ring tautomers of the new compounds were investigated by NMR, time-dependent density functional theory (TDDFT)-electronic circular dichroism, and DFT-NMR methods. Kinetic studies with rabbit muscle and human liver glycogen phosphorylases showed that the (R)-imidazolinones were 14-216 times more potent than the (S) epimers. The 2-naphthyl-substituted (R)-imidazolinone was the best inhibitor of the human enzyme (Ki 1.7 µM) and also acted on HepG2 cells (IC50 177 µM). X-ray crystallography revealed that only the (R) epimers bound in the crystal. Their inhibitory efficacy is based on the hydrogen-bonding interactions of the carbonyl oxygen and the NH of the imidazolinone ring.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Glucósidos/farmacología , Glucógeno Fosforilasa/antagonistas & inhibidores , Imidazolinas/farmacología , Compuestos de Espiro/farmacología , Animales , Dominio Catalítico , Cristalografía por Rayos X , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/metabolismo , Glucósidos/síntesis química , Glucósidos/metabolismo , Glucógeno Fosforilasa/química , Glucógeno Fosforilasa/metabolismo , Células Hep G2 , Humanos , Enlace de Hidrógeno , Imidazolinas/síntesis química , Imidazolinas/metabolismo , Cinética , Modelos Moleculares , Conformación Molecular , Unión Proteica , Conejos , Compuestos de Espiro/síntesis química , Compuestos de Espiro/metabolismo , Estereoisomerismo
13.
J Mol Biol ; 431(8): 1700-1707, 2019 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-30790629

RESUMEN

Protein degradation is critical for maintaining cellular homeostasis. The 20S proteasome is selective for unfolded, extended polypeptide chains without ubiquitin tags. Sequestration of such segments by protein partners, however, may provide a regulatory mechanism. Here we used the AP-1 complex to study how c-Fos turnover is controlled by interactions with c-Jun. We show that heterodimerization with c-Jun increases c-Fos half-life. Mutations affecting specific contact sites (L165V, L172V) or charge separation (E175D, E189D, K190R) with c-Jun both modulate c-Fos turnover, proportionally to their impact on binding affinity. The fuzzy tail beyond the structured b-HLH/ZIP domain (~165 residues) also contributes to the stabilization of the AP-1 complex, removal of which decreases c-Fos half-life. Thus, protein turnover by 20S proteasome is fine-tuned by both specific and fuzzy interactions, consistently with the previously proposed "nanny" model.


Asunto(s)
Complejo de la Endopetidasa Proteasomal/metabolismo , Mapas de Interacción de Proteínas , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Factor de Transcripción AP-1/metabolismo , Humanos , Modelos Moleculares , Unión Proteica , Proteolisis
14.
J Mol Neurosci ; 61(4): 468-478, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28168413

RESUMEN

Pituitary adenylate cyclase activating polypeptide (PACAP) is a multifunctional neuropeptide. In addition to its diverse physiological roles, PACAP has important functions in the embryonic development of various tissues, and it is also considered as a trophic factor during development and in the case of neuronal injuries. Data suggest that the development of the nervous system is severely affected by the lack of endogenous PACAP. Short-term neurofunctional outcome correlates with long-term functional deficits; however, the early neurobehavioral development of PACAP-deficient mice has not yet been evaluated. Therefore, the aim of the present study was to describe the postnatal development of physical signs and neurological reflexes in mice partially or completely lacking PACAP. We examined developmental hallmarks during the first 3 weeks of the postnatal period, during which period most neurological reflexes and motor coordination show most intensive development, and we describe the neurobehavioral development using a complex battery of tests. In the present study, we found that PACAP-deficient mice had slower weight gain throughout the observation period. Interestingly, mice partially lacking PACAP weighed significantly less than homozygous mice. There was no difference between male and female mice during the first 3 weeks. Some other signs were also more severely affected in the heterozygous mice than in the homozygous mice, such as air righting, grasp, and gait initiation reflexes. Interestingly, incisor teeth erupted earlier in mice lacking PACAP. Motor coordination, shown by the number of foot-faults on an elevated grid, was also less developed in PACAP-deficient mice. In summary, our results show that mice lacking endogenous PACAP have slower weight gain during the first weeks of development and slower neurobehavioral development regarding a few developmental hallmarks.


Asunto(s)
Peso Corporal , Actividad Motora , Sistema Nervioso/crecimiento & desarrollo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , Reflejo , Animales , Femenino , Heterocigoto , Homocigoto , Incisivo/crecimiento & desarrollo , Incisivo/metabolismo , Incisivo/ultraestructura , Masculino , Ratones , Sistema Nervioso/metabolismo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/deficiencia
15.
Materials (Basel) ; 6(2): 544-550, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28809324

RESUMEN

Biodegradable scaffolds are widely used to transplant stem cells into various tissues. Recent studies showed that living stem cells can be attached to the surface of absorbable sutures in vitro. Soaking the absorbable material polyglactin in a cell culture medium and thereby creating a stem cell biofilm on its surface may initiate the absorption process even before implantation; therefore, the physicochemical properties of the suture may be compromised in vivo. We found that pre-incubation of sutures in cell culture media in vitro results in tensile strength reduction and faster suture absorption in a rat model of muscle injury. Shorter incubation times of up to 48 h do not influence absorption or tensility; therefore, it is advisable to limit incubation times to two days for polyglactin-based cell delivery protocols.

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