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1.
Org Biomol Chem ; 19(45): 9925-9935, 2021 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-34735561

RESUMEN

Heteroanalogs of ascidian alkaloids have been synthesized, and for the first time 10 different types of saturated carbo- and heteroannulated pyridones have been obtained. A new method for the formation of decahydro[1,3]oxazolo[2,3-j]quinoline and octahydro-5H-cyclopenta[b][1,3]oxazolo[3,2-a]pyridine was proposed. The synthesis of these heterocycles is based on the three-component cyclization of trifluoroacetoacetic ester and cycloketones with 1,2- and 1,3-dinucleophiles. It was found that reactions with amino alcohols are distinguished by the possibility of isolating carbocyclopyridones of various degrees of saturation. The diastereomeric structure of the synthesized heterocycles has been studied, and the mechanism of their formation has been proposed. Antitumor, anti-influenza and analgesic agents have been found among the synthesized compounds.


Asunto(s)
Alcaloides/química , Alcaloides/farmacología , Alcaloides/síntesis química , Animales , Ciclización , Estructura Molecular , Urocordados
2.
Microbiome Res Rep ; 3(2): 19, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846022

RESUMEN

Aim: Microbiomes influence the physiology and behavior of multicellular organisms and contribute to their adaptation to changing environmental conditions. However, yeast and bacterial microbiota have usually been studied separately; therefore, the interaction between bacterial and yeast communities in the gut of Drosophila melanogaster (D. melanogaster) is often overlooked. In this study, we investigate the correlation between bacterial and yeast communities in the gut of D. melanogaster. Methods: We studied the shifts in the joint microbiome of Drosophila melanogaster, encompassing both yeasts and bacteria, during adaptation to substrate with varying salt concentrations (0%, 2%, 4%, and 7%) using plating for both yeasts and bacteria and NGS-sequencing of variable 16S rRNA gene regions for bacteria. Results: The microbiome of flies and their substrates was gradually altered at moderate NaCl concentrations (2% and 4% compared with the 0% control) and completely transformed at high salt concentrations (7%). The relative abundance of Acetobacter, potentially beneficial to D. melanogaster, decreased as NaCl concentration increased, whereas the relative abundance of the more halotolerant lactobacilli first increased, peaking at 4% NaCl, and then declined dramatically at 7%. At this salinity level, potentially pathogenic bacteria of the genera Leuconostoc and Providencia were dominant. The yeast microbiome of D. melanogaster also undergoes significant changes with an increase in salt concentration in the substrate. The total yeast abundance undergoes nonlinear changes: it is lowest at 0% salt concentration and highest at 2%-4%. At a 7% concentration, the yeast abundance in flies and their substrate is lower than at 2%-4% but significantly higher than at 0%. Conclusions: The abundance and diversity of bacteria that are potentially beneficial to the flies decreased, while the proportion of potential pathogens, Leuconostoc and Providencia, increased with an increase in salt concentration in the substrate. In samples with a relatively high abundance and/or diversity of yeasts, the corresponding indicators for bacteria were often lowered, and vice versa. This may be due to the greater halotolerance of yeasts compared to bacteria and may also indicate antagonism between these groups of microorganisms.

3.
Inorg Chem ; 52(3): 1538-43, 2013 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-23330568

RESUMEN

Mixed potassium-manganese vanadate-carbonate, K(2)Mn(3)(VO(4))(2)(CO(3)), represents a novel structure type; it has been synthesized hydrothermally from the system MnCl(2)-K(2)CO(3)-V(2)O(5)-H(2)O. Its hexagonal crystal structure was determined by single-crystal X-ray diffraction with a = 5.201(1) Å, c = 22.406(3) Å, space group P6(3)/m, Z = 2, ρ(c) = 3.371 g/cm(3), and R = 0.022. The layered structure of the compound can be described as a combination of honeycomb-type modules of [MnO(6)] octahedra and [VO(4)] tetrahedra, alternating in the [001] direction with layers of [MnCO(3)] built by [MnO(5)] trigonal bipyramids and [CO(3)] planar triangles, sharing oxygen vertices. The K(+) ions are placed along channels of the framework, elongated in the [100], [010], and [110] directions. The title compound exhibits rich physical properties reflected in a phase transition of presumably Jahn-Teller origin at T(3) = 80-100 K as well as two successive magnetic phase transitions at T(2) = 3 K and T(1) = 2 K into a weakly ferromagnetic ground state, as evidenced in magnetization, specific heat, and X-band electron spin resonance measurements. A negative Weiss temperature Θ = -114 K and strongly reduced effective magnetic moment µ(eff)(2) ~ 70 µ(B)(2) per formula unit suggest that antiferromagnetic exchange interactions dominate in the system. Divalent manganese is present in a high-spin state, S = 5/2, in the octahedral environment and a low-spin state, S = ½, in the trigonal-bipyramidal coordination.

4.
Int J Biometeorol ; 57(1): 125-36, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22434484

RESUMEN

An evaluation of performance of the System for Integrated modeLling of Atmospheric coMposition (SILAM) in application to birch pollen dispersion is presented. The system is described in a companion paper whereas the current study evaluates the model sensitivity to details of the pollen emission module parameterisation and to the meteorological input data. The most important parameters are highlighted. The reference year considered for the analysis is 2006. It is shown that the model is capable of predicting about two-thirds of allergenic alerts, with the odds ratio exceeding 12 for the best setup. Several other statistics corroborate with these estimations. Low-pollen concentration days are also predicted correctly in more than two-thirds of cases. The model experiences certain difficulties only with intermediate pollen concentrations. It is demonstrated that the most important input parameter is the near-surface temperature, the bias of which can easily jeopardise the results. The model sensitivity to random fluctuations of temperature is much lower. Other parameters important at various stages of pollen development, release, and dispersion are precipitation and ambient humidity, as well as wind direction.


Asunto(s)
Betula , Modelos Teóricos , Polen , Atmósfera , Europa (Continente) , Flores , Tiempo (Meteorología)
5.
Clocks Sleep ; 5(1): 98-115, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36975551

RESUMEN

BACKGROUND: Activity plays a very important role in keeping bodies strong and healthy, slowing senescence, and decreasing morbidity and mortality. Drosophila models of evolution under various selective pressures can be used to examine whether increased activity and decreased sleep duration are associated with the adaptation of this nonhuman species to longer or harder lives. METHODS: For several years, descendants of wild flies were reared in a laboratory without and with selection pressure. To maintain the "salt" and "starch" strains, flies from the wild population (called "control") were reared on two adverse food substrates. The "long-lived" strain was maintained through artificial selection for late reproduction. The 24 h patterns of locomotor activity and sleep in flies from the selected and unselected strains (902 flies in total) were studied in constant darkness for at least, 5 days. RESULTS: Compared to the control flies, flies from the selected strains demonstrated enhanced locomotor activity and reduced sleep duration. The most profound increase in locomotor activity was observed in flies from the starch (short-lived) strain. Additionally, the selection changed the 24 h patterns of locomotor activity and sleep. For instance, the morning and evening peaks of locomotor activity were advanced and delayed, respectively, in flies from the long-lived strain. CONCLUSION: Flies become more active and sleep less in response to various selection pressures. These beneficial changes in trait values might be relevant to trade-offs among fitness-related traits, such as body weight, fecundity, and longevity.

6.
Acta Crystallogr C Struct Chem ; 71(Pt 6): 465-73, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26044328

RESUMEN

New decavanadate minerals, the products of the leaching or metasomatic processes, are possible in nature via Na/Rb removal/inclusion reactions. As part of our search for novel vanadate phases with varying functionalities, a new phase, tetrarubidium hexaaquasodium hydrogen decavanadate tetrahydrate, Rb4[Na(H2O)6][HV10O28]·4H2O, has been synthesized by the hydrothermal technique at 553 K. Ten shared edges of V-centred octahedra form monoprotonated decavanadate cages, which are joined together via hydrogen bonds into one-dimensional chains parallel to the [101] direction. Within these chains, H atoms are sandwiched between neighbouring polyanions. Na and Rb atoms and H2O molecules occupy interstices flanked by the anionic chains providing additional crosslinking in the structure. This compound is the second decavanadate with P2/n symmetry. Structural relationships among protonated and deprotonated decavanadates with inorganic cations, including minerals of the pascoite group, are discussed.

7.
J Altern Complement Med ; 21(11): 720-4, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26302046

RESUMEN

OBJECTIVE: To perform an initial assessment of the potential of using the gas discharge visualization (GDV) technique to identify patients with colon neoplasias. METHODS: The GDV camera (also known as the electrophotonic imaging camera) was used to assess the participants. Colonoscopy was performed on all 78 participants, followed by a GDV scan. The control group consisted of 22 people. An endoscopic examination identified colon tumors in the remaining 56 participants. Participant ages ranged from 45 to 86 years (mean, 64.6 ± 1.2 years). The study analyzed GDV images of each patient's fingers, presenting a whole-body view, as well as separate sectors corresponding to the organs in question. RESULTS: There was a significant number of differences between the control group and the patients with colon tumors. The dynamic of the parameters was examined as the level of tumor dysplasia (neoplasia) varied. The values of the following parameters decreased in the control group as compared to the patients with cancerous polyps: normalized luminescence area, internal noise, contour radius, and average luminescence intensity. The values of the following parameters increased in the control group: radius of the inscribed circle, contour line length, area of luminescence, contour line fractality, contour line entropy, and form coefficients. CONCLUSION: This pilot study demonstrated a statistical difference between the GDV parameters of patients with colon tumors and the control group. These findings warrant a more in-depth study of the potential for GDV technique in screening programs.


Asunto(s)
Neoplasias del Colon/diagnóstico , Colonoscopía/métodos , Diagnóstico por Imagen/métodos , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Pólipos del Colon/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad
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