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排序方式: 共有379条查询结果,搜索用时 125 毫秒
291.
Joanna Kumierz Weronika Frk Ewelina Mynarska Beata Franczyk Jacek Rysz 《International journal of molecular sciences》2021,22(18)
Arterial hypertension (AH) is a major risk factor for the development of cardiovascular diseases. It is estimated that the disease affects between 10% and 20% of the adult population and is responsible for 5.8% of all deaths worldwide. Several pathophysiologic factors are crucial in AH, including inappropriate activation of the renin-angiotensin-aldosterone system, oxidative stress and inflammation. The heart, kidney, brain, retina and arterial blood vessels are prime targets of hypertensive damage. Uncontrolled and untreated AH accelerates the damage to these organs and could cause their failure. Damage to these organs could also manifest as coronary heart disease, cognitive impairment, retinopathy or optic neuropathy. For better understanding, it is important to analyze molecular factors which take part in pathogenesis of AH and hypertension-related target organ damage. In our paper, we would like to focus on molecular interactions of AH in the heart, blood vessels, brain and kidneys. We focus on matrix metalloproteinases, the role of immune system, the renin-angiotensin-aldosterone system and oxidative stress in hypertensive induced organ damage. 相似文献
292.
Preparation and properties of new lactose-based surfactants 总被引:1,自引:0,他引:1
Kazimiera A. Wilk Ludwik Syper Bogdan Burczyk Irena Maliszewska Marek Jon Beata W. Domagalska 《Journal of surfactants and detergents》2001,4(2):155-161
A new group of nonionic saccharide-based surfactants, N-alkanoyl-N-methyllactitolamines (alkanoyl: decanoyl, lauroyl, myristoyl, palmitoyl, stearoyl), were synthesized and characterized. Surface
properties such as critical micelle concentration, standard free energy of adsorption, standard free energy of micellization,
surface tension reduction efficiency, effectiveness of surface tension reduction, surface excess concentration, and surface
area demand per molecule as well as foaming properties (i.e., foam volume and foam stability), contact angle, antiraicrobial
activity, and biodegradability were determined. The selected performance properties were evaluated in relation to commercially
available alkyl polyglucosides (Glukopon 600 EC(HH)-a Henkel product), and oligooxyethylenated decyl (C10E4) and dodecyl (E12E5) alcohols. The foaming-stabilizing effect and contact angle suggest that the lactose-derived surfactants that were studied
share some common properties with alkyl polyglucosides that are different from those with an oligooxyethylene grouping. All
tested N-alkanoyl-N-methyllactitolamines were practically nontoxic to bacteria and yeasts. These compounds are readily biodegradable in the Closed
Bottle test inoculated with activated sludge. N-Alkanoyl-N-methyllactitolamines with lower chain lengths (C10–C14) biodegraded at a slightly faster rate. Biological properties showed that this class of compounds fulfills all requirements
needed for environmental acceptance. 相似文献
293.
Daria Baranowska Tomasz Kdzierski Magorzata Aleksandrzak Ewa Mijowska Beata Zieliska 《International journal of molecular sciences》2021,22(23)
In this contribution, the effect of hydrogenation conditions atmosphere (temperature and time) on physicochemical properties and photocatalytic efficiency of graphitic carbon nitride (g-C3N4, gCN) was studied in great details. The changes in the morphology, chemical structure, optical and electrochemical properties were carefully investigated. Interestingly, the as-modified samples exhibited boosted photocatalytic degradation of Rhodamine B (RhB) with the assistance of visible light irradiation. Among modified gCN, the sample annealed at 500 °C for 4 h (500-4) in H2 atmosphere exhibited the highest photocatalytic activity—1.76 times higher compared to pristine gCN. Additionally, this sample presented high stability and durability after four cycles. It was noticed that treating gCN with hydrogen at elevated temperatures caused the creation of nitrogen vacancies on gCN surfaces acting as highly active sites enhancing the specific surface area and improving the mobility of photogenerated charge carriers leading to accelerating the photocatalytic activity. Therefore, it is believed that detailed optimization of thermal treatment in a hydrogen atmosphere is a facile approach to boost the photoactivity of gCN. 相似文献
294.
Sandra Grska-Jakubowska Marzenna Klimaszewska Piotr Podsadni Beata Kaleta Radosaw Zagodon Sabina Grska Andrzej Gamian Tomasz Strczek Czesaw Kapusta Marcin Cielak Julia Ka
mierczak-Baraska Barbara Nawrot Jadwiga Turo 《International journal of molecular sciences》2021,22(23)
In continuation of our research on the influence of selenium incorporation on the biosynthesis, structure, and immunomodulatory and antioxidant activities of polysaccharides of fungal origin, we have isolated from a post-culture medium of Lentinula edodes a selenium (Se)-containing exopolysaccharide fraction composed mainly of a highly branched 1-6-α-mannoprotein of molecular weight 4.5 × 106 Da, with 15% protein component. The structure of this fraction resembled mannoproteins isolated from yeast and other mushroom cultures, but it was characterized by a significantly higher molecular weight. X-ray absorption fine structure spectral analysis in the near edge region (XANES) suggested that selenium in the Se-exopolysaccharide structure was present mainly at the IV oxidation state. The simulation analysis in the EXAFS region suggested the presence of two oxygen atoms in the region surrounding the selenium. On the grounds of our previous studies, we hypothesized that selenium-enriched exopolysaccharides would possess higher biological activity than the non-Se-enriched reference fraction. To perform structure–activity studies, we conducted the same tests of biological activity as for previously obtained mycelial Se-polyglucans. The Se-enriched exopolysaccharide fraction significantly enhanced cell viability when incubated with normal (human umbilical vein endothelial cells (HUVEC)) cells (but this effect was absent for malignant human cervical HeLa cells) and this fraction also protected the cells from oxidative stress conditions. The results of tests on the proliferation of human peripheral blood mononuclear cells suggested a selective immunosuppressive activity, like previously tested Se-polyglucans isolated from L. edodes mycelium. The Se-exopolysaccharide fraction, in concentrations of 10–100 µg/mL, inhibited human T lymphocyte proliferation induced by mitogens, without significant effects on B lymphocytes. As with previously obtained Se-polyglucans, in the currently tested Se-polymannans, the selenium content increased the biological activity. However, the activity of selenium exopolysaccharides in all tests was significantly lower than that of previously tested mycelial isolates, most likely due to a different mode of selenium binding and its higher degree of oxidation. 相似文献
295.
Marcin Kolasa Grzegorz Galita Ireneusz Majsterek Ewa Kucharska Katarzyna Czerczak Joanna Wasko Angelika Becht Justyna Fraczyk Anna Gajda Lukasz Pietrzak Lukasz Szymanski Agnieszka Krakowiak Zbigniew Draczynski Beata Kolesinska 《International journal of molecular sciences》2021,22(24)
The aim of the research was to check whether it is possible to use fragments of type IV collagen to obtain, as a result of self-assembling, stable spatial structures that could be used to prepare new materials useful in regenerative medicine. Collagen IV fragments were obtained by using DMT/NMM/TosO− as a coupling reagent. The ability to self-organize and form stable spatial structures was tested by the CD method and microscopic techniques. Biological studies covered: resazurin assay (cytotoxicity assessment) on BJ, BJ-5TA and C2C12 cell lines; an alkaline version of the comet assay (genotoxicity), Biolegend Legendplex human inflammation panel 1 assay (SC cell lines, assessment of the inflammation activity) and MTT test to determine the cytotoxicity of the porous materials based on collagen IV fragments. It was found that out of the pool of 37 fragments (peptides 1–33 and 2.1–2.4) reconstructing the outer sphere of collagen IV, nine fragments (peptides: 2, 4, 5, 6, 14, 15, 25, 26 and 30), as a result of self-assembling, form structures mimicking the structure of the triple helix of native collagens. The stability of spatial structures formed as a result of self-organization at temperatures of 4 °C, 20 °C, and 40 °C was found. The application of the MST method allowed us to determine the Kd of binding of selected fragments of collagen IV to ITGα1β1. The stability of the spatial structures of selected peptides made it possible to obtain porous materials based on their equimolar mixture. The formation of the porous materials was found for cross-linked structures and the material stabilized only by weak interactions. All tested peptides are non-cytotoxic against all tested cell lines. Selected peptides also showed no genotoxicity and no induction of immune system responses. Research on the use of porous materials based on fragments of type IV collagen, able to form stable spatial structures as scaffolds useful in regenerative medicine, will be continued. 相似文献
296.
Anna Jaromin Beata Gryzo Marek Jamrozik Silvia Parapini Nicoletta Basilico Marek Cega Donatella Taramelli Agnieszka Zagrska 《International journal of molecular sciences》2021,22(24)
Malaria is still one of the most dangerous infectious diseases and the emergence of drug resistant parasites only worsens the situation. A series of new tetrahydro-β-carbolines were designed, synthesized by the Pictet–Spengler reaction, and characterized. Further, the compounds were screened for their in vitro antiplasmodial activity against chloroquine-sensitive (D10) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Moreover, molecular modeling studies were performed to assess the potential action of the designed molecules and toxicity assays were conducted on the human microvascular endothelial (HMEC-1) cell line and human red blood cells. Our studies identified N-(3,3-dimethylbutyl)-1-octyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b] indole-3-carboxamide (7) (a mixture of diastereomers) as the most promising compound endowed with the highest antiplasmodial activity, highest selectivity, and lack of cytotoxicity. In silico simulations carried out for (1S,3R)-7 provided useful insights into its possible interactions with enzymes essential for parasite metabolism. Further studies are underway to develop the optimal nanosized lipid-based delivery system for this compound and to determine its precise mechanism of action. 相似文献
297.
Damila M. Bogusawska Micha Skulski Beata Machnicka Stanisaw Potoczek Sebastian Kraszewski Kazimierz Kuliczkowski Aleksander F. Sikorski 《International journal of molecular sciences》2021,22(20)
Hereditary spherocytosis (HS), the most commonly inherited hemolytic anemia in northern Europeans, comprises a group of diseases whose heterogeneous genetic basis results in a variable clinical presentation. High-throughput genome sequencing methods have made a leading contribution to the recent progress in research on and diagnostics of inherited diseases and inspired us to apply whole exome sequencing (WES) to identify potential mutations in HS. The data presented here reveal a novel mutation probably responsible for HS in a single Polish family. Patients with clinical evidence of HS (clinical symptoms, hematological data, and EMA test) were enrolled in the study. The examination of the resulting WES data showed a number of polymorphisms in 71 genes associated with known erythrocyte pathologies (including membranopathies, enzymopathies, and hemoglobinopathies). Only a single SPTB gene variant indicated the possible molecular mechanism of the disease in the studied family. The new missense mutation p.C183Y was identified using WES in the SPTB gene, which is most likely the cause of clinical symptoms typical of hereditary spherocytosis (membranopathy) due to structural and functional impairments of human β-spectrin. This mutation allows for a better understanding of the molecular mechanism(s) of one of the membranopathies, hereditary spherocytosis. 相似文献
298.
The effect of the stage of lactation, the number of foals and age of the mare on changes in the fat content and fatty acid composition of colostrum and milk of primitive Konik horses was investigated. Colostrum and milk samples from 12 lactating mares were collected at the beginning of lactation, on the days 1 and 2 after foaling and then, starting from the first month of lactation, at 4-week intervals up to the sixth month of lactation. Significant differences were observed in fat content as well as the composition of some analysed fatty acids between colostrum and milk of mares of the Konik breed. The number of foalings and the age of mares did not have a statistically significant effect on the fat content in milk and had only a slight effect on the fatty acid composition. Milk produced by mares of the Konik breed is characterized by a considerable content of polyene fatty acids with 18 carbon atoms, a low ratio of n-6 fatty acids to n-3 fatty acids as well as low, highly advantageous values of atherogenic and thrombogenic indices. 相似文献
299.
Effect of supplementation of cows diet with linseed and fish oil and different variants of β‐lactoglobulin on fatty acid composition and antioxidant capacity of milk
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300.
Aldonamide-type gemini surfactants: Synthesis, structural analysis, and biological properties 总被引:1,自引:0,他引:1
Kazimiera A. Wilk Ludwik Syper Beata W. Domagalska Urszula Komorek Irena Maliszewska Roman Gancarz 《Journal of surfactants and detergents》2002,5(3):235-244
A new group of nonionics, so-called sugar surfactants having a gemini structure, N,N′-bisalkyl-N,N′-bis[(3-gluconylamido)propyl]ethylenediamines [bis(C
n
GA): C
n
=n-C8H17, n-C12H25], N,N′-bisdodecyl-N,N′-bis[(3-glucoheptonylamido)propyl]ethylenediamine [bis(C12GH)], and N,N′-bisalkyl-N,N′-bis[(3-lactobionylamido)propyl]ethylenediamines [bis(C
n
LA): C
n
=n-C8H17, n-C12H25], were prepared in a convenient four-step procedure from easily accessible reagents. Their structure and purity were confirmed
by means of elemental analysis, electrospray ionization MS (ESI-MS), and NMR spectra—1H, 13C, 1H−13C COSY, and distortionless enhancement by polarization transfer. All tested surfactants were practically nontoxic to gram-negative
bacteria and fungi, but they inhibited the growth of some gram-positive bacteria. From the results of the Closed Bottle test
(OECD Guideline 301D) for biodegradability measurements, it was concluded that the tested aldonamide gemini structures are
biodegraded by environmental microorganisms to 16–55% of the initial levels by day 28, the extent depending on both the aldonamide
type and the alkyl chain length. Consequently, N,N′-bisalkyl-N,N′-bis[(3-aldonylamido)propyl]ethylenediamines are a surfactant class having low ecotoxicity and fulfilling requirements desired
from an ecological standpoint. 相似文献