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91.
Katarzyna Grzybowska Marzena Rams-Baron Kinga ucak Andrzej Grzybowski Marian Paluch 《International journal of molecular sciences》2022,23(17)
In this paper, we thoroughly investigated the physical stability of the anti-inflammatory drug etoricoxib, which has been reported earlier to be resistant to recrystallization in its glassy and supercooled states at ambient pressure. Our unique application of the standard refractometry technique showed that the supercooled liquid of the drug was able to recrystallize during isothermal experiments in atmospheric conditions. This enabled us to determine the crystallization onset timescale and nucleation energy barrier of etoricoxib for the first time. As the physical instability of etoricoxib requires working out an efficient method for improving the drug’s resistance to recrystallization to maintain its amorphous form utility in potential pharmaceutical applications, we focused on finding a solution to this problem, and successfully achieved this purpose by preparing binary mixtures of etoricoxib with octaacetylmaltose. Our detailed thermal, refractometry, and molecular dynamics studies of the binary compositions near the glass transition revealed a peculiar behavior of the glass transition temperatures when changing the acetylated disaccharide concentration in the mixtures. Consequently, the anti-plasticization effect on the enhancement of physical stability could be excluded, and a key role for specific interactions in the improved resistance to recrystallization was expected. Invoking our previous results obtained for etoricoxib, the chemically similar drug celecoxib, and octaacetylmaltose, we formulated a hypothesis about the molecular mechanisms that may cause an impediment to crystal nuclei formation in the amorphous mixtures of etoricoxib with octaacetylmaltose. The most plausible scenario may rely on the formation of hydrogen-bonded heterodimers of the drug and excipient molecules, and the related drop in the population of the etoricoxib homodimers, which disables the nucleation. Nevertheless, this hypothesis requires further investigation. Additionally, we tested some widely discussed correlations between molecular mobility and crystallization properties, which turned out to be only partially satisfied for the examined mixtures. Our findings constitute not only a warning against manufacturing the amorphous form of pure etoricoxib, but also evidence for a promising outcome for the pharmaceutical application of the amorphous compositions with octaacetylmaltose. 相似文献
92.
Magorzata Dawidowska Natalia Makowska-Malak Monika Drobna-
ledziska Maria Kosmalska Roman Jaksik Donata Szymczak Magorzata Jarmu-Szymczak Alicja Sadowska-Klasa Marzena Wojtaszewska ukasz Sdek Tomasz Wrbel Jan Maciej Zaucha Tomasz Szczepaski Krzysztof Lewandowski Sebastian Giebel Micha Witt 《International journal of molecular sciences》2022,23(17)
93.
Kamil Wawrowicz Agnieszka Majkowska-Pilip Marzena Szwed Kinga elechowska-Matysiak Ewelina Chajduk Aleksander Bilewicz 《International journal of molecular sciences》2022,23(23)
Overcoming the limitations for efficient and selective drug delivery is one of the most challenging obstacles for newly designed anticancer agents. In this study, we present two types of platinum-based nanoparticles (NP), ultrasmall 2 nm PtNPs and core-shell 30 nm Au@Pt, which can be highly cytotoxic in an oxidative environment and remain biologically inactive in cells with lower oxidative status. Our research highlighted the differences in platinum nanoparticle-induced chemotoxicity and is the first study examining its mechanism as a substantial aspect of Au@Pt/PtNPs biological activity. Selectively induced oxidative stress was found to be a primary trigger of NPs’ toxicity. Significant differences between Au@Pt and PtNPs were observed especially during 24 h treatment, due to successful intranuclear PtNPs location (~13% of internalized fraction). Reactive oxygen species (ROS)-level induced from both NPs types were similar, while reduction of reduced glutathione (GSH) intracellular content was stronger after treatment with PtNPs. Any biological activity was found in HER2+ breast cancer cells, which have only slightly increased oxidative status. Platinum-containing nanoparticles are an interesting tool for the improvement of selectivity in anticancer therapies against hepatocellular carcinoma (HCC). Due to intranuclear uptake, 2 nm PtNPs seems to be more promising for further research for HCC therapy. 相似文献
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96.
Dominik S. Skiba Piotr Szczepaniak Mateusz Siedliski Piotr Poznaski Marzena azarczyk Kinga Jaskua Piotr Religa Mariusz Sacharczuk Zbigniew Gaciong 《International journal of molecular sciences》2021,22(8)
The opioid system is well-known for its role in modulating nociception and addiction development. However, there are premises that the endogenous opioid system may also affect blood pressure. The main goal of the present study was to determine the impact of different endogenous opioid system activity and its pharmacological blockade on blood pressure. Moreover, we examined the vascular function in hyper- and hypoactive states of the opioid system and its pharmacological modification. In our study, we used two mouse lines which are divergently bred for high (HA) and low (LA) swim stress-induced analgesia. The obtained results indicated that individuals with low endogenous opioid system activity have higher basal blood pressure compared to those with a hyperactive opioid system. Additionally, naloxone administration only resulted in the elevation of blood pressure in HA mice. We also showed that the hypoactive opioid system contributes to impaired vascular relaxation independent of endothelium, which corresponded with decreased guanylyl cyclase levels in the aorta. Together, these data suggest that higher basal blood pressure in LA mice is a result of disturbed mechanisms in vascular relaxation in smooth muscle cells. We believe that a novel mechanism which involves endogenous opioid system activity in the regulation of blood pressure will be a promising target for further studies in hypertension development. 相似文献
97.
Homopolymerization of styrenic monomers (St, p-Me-St, p-tBu-St, p-tBuO-St) and their copolymerization with ethylene, with the use of [(tBu2O2NN′)ZrCl]2(μ-O) ( 1 ) and (tBu2O2NN′)TiCl2 ( 2 ), where tBu2O2NN′ = Me2N(CH2)2N(CH2-2-O−-3,5-tBu2-C6H2)2, is explored in the presence of MMAO and (iBu)3Al/Ph3CB(C6F5)4. The ethylene/styrenic monomers copolymerization with 1 /MMAO produces exclusively copolymers with high activity and good comonomer incorporation whereas the other catalytic systems yield mixtures of copolymers and homopolymers. The use of p-alkyl styrene derivatives instead of styrene raises the catalytic activity, comonomer incorporation and molecular weights of the copolymers. Complex 2 exhibits higher activity in homopolymerization of styrenic monomers than 1 irrespective of the kind of the activator employed. A clear dependence is observed for the molecular weight and catalyst activity against the kind of the styrenic monomer. The obtained polymers were atactic and only the complex 2 , when activated by MMAO, promoted the highly syndiospecific polymerization of p-Me-St and p-tBu-St. Poly(p-tBuO-St) exhibits fiber-forming properties. 相似文献
98.
Anna Janas Paulina Pecyna Prof. Marzena Gajecka Prof. Franz Bartl Prof. Piotr Przybylski 《ChemMedChem》2020,15(16):1529-1551
Desosamines of azithromycin (AZM) and clarithromycin (CLA) were modified by N-alkylation or nucleophilic substitution at the carbonyl/CuAAC sequence. Biological studies revealed a higher antibacterial potency of quaternary N-alkylammonium bromides of CLA as compared to AZM. SAR studies of CLA salts, including biological, conformation and molecular-docking analysis, enriched by physicochemical parameters, showed the importance of less bulky and unsaturated substituent for an efficient docking mode at the ribosomal tunnel and good antibacterial potency against clinical and standard Streptococcus pneumoniae and Streptococcus pyogenes strains (MICs 0.25 or 0.5 μg/mL). These CLA salts also have an at least threefold lower cytotoxicity than reference antibiotics at comparable antibacterial activity against the S. pneumoniae clinical strain. Differences in antibacterial effects noted for AZM and CLA salts bearing less bulky N-substituents can be better understood when their binding modes in the ribosomal tunnel are considered rather than their common low lipophilicity and excellent water solubility. 相似文献
99.
Anna Szeliga Anna Calik-Ksepka Marzena Maciejewska-Jeske Monika Grymowicz Katarzyna Smolarczyk Anna Kostrzak Roman Smolarczyk Ewa Rudnicka Blazej Meczekalski 《International journal of molecular sciences》2021,22(5)
Premature ovarian insufficiency (POI), previously known as premature ovarian failure or premature menopause, is defined as loss of ovarian function before the age of 40 years. The risk of POI before the age of 40 is 1%. Clinical symptoms develop as a result of estrogen deficiency and may include amenorrhea, oligomenorrhea, vasomotor instability (hot flushes, night sweats), sleep disturbances, vulvovaginal atrophy, altered urinary frequency, dyspareunia, low libido, and lack of energy. Most causes of POI remain undefined, however, it is estimated that anywhere from 4–30% of cases are autoimmune in origin. As the ovaries are a common target for autoimmune attacks, an autoimmune etiology of POI should always be considered, especially in the presence of anti-oocyte antibodies (AOAs), autoimmune diseases, or lymphocytic oophoritis in biopsy. POI can occur in isolation, but is often associated with other autoimmune conditions. Concordant thyroid disorders such as hypothyroidism, Hashimoto thyroiditis, and Grave’s disease are most commonly seen. Adrenal autoimmune disorders are the second most common disorders associated with POI. Among women with diabetes mellitus, POI develops in roughly 2.5%. Additionally, autoimmune-related POI can also present as part of autoimmune polyglandular syndrome (APS), a condition in which autoimmune activity causes specific endocrine organ damage. In its most common presentation (type-3), APS is associated with Hashomoto’s type thyroid antibodies and has a prevalence of 10–40%. 21OH-Antibodies in Addison’s disease (AD) can develop in association to APS-2. 相似文献
100.