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991.
Ewa Malatynska Glenda J. Crites David Harrawood Rachel Goldenberg G. Keith Matheson 《Brain research》2000,869(1-2)
Antidepressants act at the GABAA receptor to inhibit GABA-stimulated 36Cl− influx and GABA reduction of [35S]TBPS binding. This study examined how selective knock-down (via antisense oligodeoxynucleotides, aODNs) of GABAA receptor subunits modified antidepressant activity. The specific aODNs used were for the α1, β1, β2 or γ2 subunits of the GABAA receptor. The aODN microinjections reduced corresponding GABAA receptor subunit mRNA levels by 30–40% as assessed by RT-PCR. The inhibitory effect of the antidepressants amitriptyline and mianserin on GABA-stimulated 36Cl− influx was decreased after microinjections of α1, β1, or β2 subunit aODNs but potentiated after microinjections of γ2 subunit aODNs. This pattern of aODNs effect on amitriptyline and mianserin modulation of GABA-stimulated 36Cl− influx was the same for both antidepressants and similar to GABA but different than that of diazepam and bicuculline. We conclude that multiple subunits of the GABAA receptor regulate the effect of amitriptyline and mianserin on the GABAA receptor chloride ionophore complex. However, the exact identity of the subunit mediating the direct or allosteric modulation of the antidepressant effect on GABA-stimulated 36Cl− influx remains unclear. 相似文献
992.
Joanna Klebeko Paula Ossowicz-Rupniewska Anna Nowak Ewa Janus Wiktoria Duchnik Urszula Adamiak-Giera ukasz Kucharski Piotr Prowans Jan Petriczko Norbert Czapla Piotr Bargiel Marta Markowska Adam Klimowicz 《Materials》2021,14(21)
This paper aimed to evaluate the effect of vehicle and chemical modifications of the structure of active compounds on the skin permeation and accumulation of ibuprofen [IBU]. In vitro permeation experiments were performed using human abdominal skin and Strat-M™ membrane. The HPLC method was used for quantitative determinations. The formulations tested were hydrogels containing IBU and its derivatives and commercial gel with ibuprofen. The results obtained indicate that Celugel® had an enhancing effect on the skin penetration of IBU. The average cumulative mass of [IBU] after 24 h permeation test from Celugel® formulation through human skin was over 3 times higher than for the commercial product. Three ibuprofen derivatives containing [ValOiPr][IBU], [ValOPr][IBU], and [ValOBu][IBU] cation were evaluated as chemical penetration enhancers. The cumulative mass after 24 h of penetration was 790.526 ± 41.426, 682.201 ± 29.910, and 684.538 ± 5.599 μg IBU cm−2, respectively, compared to the formulation containing unmodified IBU-429.672 ± 60.151 μg IBU cm−2. This study demonstrates the perspective of the transdermal hydrogel vehicle in conjunction with the modification of the drug as a potential faster drug delivery system. 相似文献
993.
Maria Śmiałowska Helena Domin Barbara Zięba Ewa Koźniewska Radosław Michalik Piotr Piotrowski Małgorzata Kajta 《Neuropeptides》2009,43(3):235-249
It is generally assumed that neurodegeneration is connected with glutamatergic hyperactivity, and that neuropeptide Y (NPY) inhibits glutamate release. Some earlier studies indicated that NPY may have neuroprotective effect; however, the results obtained so far are still divergent, and the role of different Y receptors remains unclear. Therefore in the presented study we investigated the neuroprotective potential of NPY and its Y2, Y5 or Y1 receptor (R) ligands against the kainate (KA)-induced excitotoxicity in neuronal cultures in vitro, as well as in vivo after intrahippocampal KA injection and also in an ischemic middle cerebral artery occlusion model after intraventricular injection of Y2R agonist. NPY compounds were applicated 30 min, 1, 3 or 6 h after the start of the exposure to KA, or 30 min after the onset of ischemia. Our results indicate the neuroprotective activity of NPY and its Y2R and Y5R ligands against the kainate-induced excitotoxicity in primary cortical and hippocampal cultures. Importantly, NPY was effective when given as late as 6 h, while Y2R or Y5R agonists 3 h, after starting the exposure to KA. In in vitro studies those protective effects were inhibited by the respective receptor antagonists. Neuroprotection was also observed in vivo after intrahippocampal injection of Y2R and Y5R agonists 30 min or 1 h after KA. No protection was found either in vitro or in vivo after the Y1R agonist. The Y2R agonist also showed neuroprotective activity in the ischemic model. The obtained results indicate that neuropeptide Y produces neuroprotective effect via Y2 and Y5 receptors, and that the compounds may be effective after delayed application. 相似文献
994.
Viktoria Hawrykowicz Danuta Lietz-Kijak Karolina Ka
mierczak-Siedlecka Joanna Soek-Pastuszka Laura Stachowska Marcin Folwarski Miosz Parczewski Ewa Stachowska 《Nutrients》2021,13(10)
Background: The main nutritional consequences of COVID-19 include reduced food intake, hypercatabolism, and rapid muscle wasting. Some studies showed that malnutrition is a significant problem among patients hospitalized due to COVID-19 infection, and the outcome of patients with SARS-CoV-2 is strongly associated with their nutritional status. The purpose of this study was to collect useful information about the possible elements of nutritional and probiotic therapy in patients infected with the SARS-CoV-2 virus. Methods: A narrative review of the literature, including studies published up to 13 September 2021. Results: Probiotics may support patients by inhibiting the ACE2 receptor, i.e., the passage of the virus into the cell, and may also be effective in suppressing the immune response caused by the proinflammatory cytokine cascade. In patients’ diet, it is crucial to ensure an adequate intake of micronutrients, such as omega-3 fatty acids (at 2–4 g/d), selenium (300–450 μg/d) and zinc (30–50 mg/d), and vitamins A (900–700 µg/d), E (135 mg/d), D (20,000–50,000 IU), C (1–2 g/d), B6, and B12. Moreover, the daily calorie intake should amount to ≥1500–2000 with 75–100 g of protein. Conclusion: In conclusion, the treatment of gut dysbiosis involving an adequate intake of prebiotic dietary fiber and probiotics could turn out to be an immensely helpful instrument for immunomodulation, both in COVID-19 patients and prophylactically in individuals with no history of infection. 相似文献
995.
Karolina Kowalska Marta Justyna Kozie Kinga Anna Urbanek Dominika Ewa Habrowska-Grczyska Kamila Domiska Agnieszka Wanda Piastowska-Ciesielska 《Toxins》2021,13(11)
Alternaria toxins are considered as emerging mycotoxins, however their toxicity has not been fully evaluated in humans. Alternariol (AOH), the most prevalent Alternaria mycotoxin, was previously reported to be genotoxic and to affect hormonal balance in cells; however, its direct molecular mechanism is not known. The imbalance in androgen/estrogen ratio as well as chronic inflammation are postulated as factors in prostate diseases. The environmental agents affecting the hormonal balance might participate in prostate carcinogenesis. Thus, this study evaluated the effect of two doses of AOH on prostate epithelial cells. We observed that AOH in a dose of 10 µM induces oxidative stress, DNA damage and cell cycle arrest and that this effect is partially mediated by estrogen receptor β (ERβ) whereas the lower tested dose of AOH (0.1 µM) induces only oxidative stress in cells. The modulation of nuclear erythroid-related factor 2 (Nrf2) was observed in response to the higher dose of AOH. The use of selective estrogen receptor β (ERβ) inhibitor PHTPP revealed that AOH-induced oxidative stress in both tested doses is partially dependent on activation of ERβ, but lack of its activation did not protect cells against AOH-induced ROS production or DNA-damaging effect in case of higher dose of AOH (10 µM). Taken together, this is the first study reporting that AOH might affect basic processes in normal prostate epithelial cells associated with benign and malignant changes in prostate tissue. 相似文献
996.
Paula Ossowicz-Rupniewska Anna Nowak Joanna Klebeko Ewa Janus Wiktoria Duchnik Urszula Adamiak-Giera ukasz Kucharski Piotr Prowans Jan Petriczko Norbert Czapla Piotr Bargiel Marta Markowska Adam Klimowicz 《Materials》2021,14(22)
The effect of transdermal vehicle (Pentravan®) on skin permeability was examined for unmodified ibuprofen (IBU) and ion pairs of ibuprofen with new L-valine alkyl esters [ValOR][IBU]. The percutaneous permeation across the human skin and transdermal diffusion test model (Strat-M® membranes) of ibuprofen and its structural modification were measured and compared using Franz diffusion cells. For comparison, the penetration of ibuprofen from a commercial product was also investigated. The cumulative amount of drug permeated through human skin at the end of the 24 h study was highest for ibuprofen derivatives containing propyl (C3), isopropyl (C3), ethyl (C2), and butyl (C4) esters. For Strat-M®, the best results were obtained with the alkyl chain length of the ester from C2 to C5. The permeation profiles and parameters were appointed, such as steady-state flux, lag time, and permeability coefficient. It has been shown that L-valine alkyl ester ibuprofenates, with the propyl, butyl, and amyl chain, exhibit a higher permeation rate than ibuprofen. The diffusion parameters of analyzed drugs through human skin and Strat-M® were similar and with good correlation. The resulting Pentravan-based creams with ibuprofen in the form of an ionic pair represent a potential alternative to other forms of the drug-containing analgesics administered transdermally. Furthermore, the Strat-M® membranes can be used to assess the permeation of transdermal preparations containing anti-inflammatory drugs. 相似文献
997.
Magdalena Wyszyska Ewa Biaoyt-Bujak Grzegorz Chladek Aleksandra Czelakowska Rafa Rj Agata Biaoyt Olaf Gruca Monika Nitsze-Wierzba Jacek Kasperski Magorzata Skucha-Nowak 《Materials》2021,14(22)
Abrasions and pressure ulcers on the oral mucosa are most often caused by excessive pressure or incorrect fitting of the denture. The use of soft relining materials can eliminate pain sensations and improve patient comfort. The main functional feature of soft elastomeric materials is the ability to discharge loads from the tissues of the mucosa. (1) Background: The aim of the work was a comparative laboratory study of ten materials used for the soft lining of acrylic dentures. (2) Methods: There were materials based on acrylates (Vertex Soft, Villacryl Soft, Flexacryl Soft) and silicones (Sofreliner Tough Medium, Sofreliner Tough Medium, Ufi Gel SC, GC Reline Soft, Elite Soft Relining, Molloplast). Laboratory tests include the analysis of the tensile bond strength between the relining material and the acrylic plate of the prosthesis. The tests were conducted taking into account 90-day term aging in the distilled water environment based on the methodology presented in the European Standard ISO 10139-2. (3) Results: After three months of observation, the highest strength of the joint was characterized by Flexacryl Soft acrylic, for which the average value was 2.5 MPa. The lowest average value of 0.89 MPa was recorded for the GC Reline Soft silicone material. Over time, an increase in the value of the strength of the combination of acrylic materials and a decrease in these values in the case of silicone materials was observed. (4) Conclusion: Each of the tested silicone materials showed all three types of damage, from adhesive to mixed to cohesive. All acrylic-based materials showed an adhesive type of failure. Time did not affect the type of destruction. 相似文献
998.
999.
Aleksandra Grska Ewa Jaboska Edyta Reszka Marek Niedoszytko Magdalena Lange Marta GruchaaNiedoszytko Justyna Jarczak Dominik Strapagiel Magdalena GrskaPonikowska Paulina Bastian Iwona PelikantMaecka Leszek Kalinowski Bogusaw Nedoszytko 《Clinical and translational allergy》2021,11(9)
BackgroundMastocytosis is a clinically heterogeneous, usually acquired disease of the mast cells with a survival time that depends on the onset of the disease and ranges from skin‐limited to systemic disease, including indolent and more aggressive variants. The crucial element in pathogenesis is the presence of oncogenic KIT somatic mutation D816V. Further epigenetic alterations are responsible for regulating the expression of genes. It is essential to identify indicators of disease progression, and the specific clinical picture to establish an appropriate therapeutic strategy.ObjectiveThe aim of this study was to analyze the relation of mastocytosis symptoms and epigenetic changes, and to identify epigenetic predictors of the disease.MethodsGlobal DNA methylation profile analysis was performed in peripheral blood collected from 73 patients with indolent systemic mastocytosis (ISM) and 43 healthy adult volunteers. Levels of 5‐methylcytosine (5‐mC) and 5‐hydroxymethylcytosine (5‐hmC) were determined using an ELISA‐based method, while the methylation of the Alu and LINE‐1 repeats were assayed with the quantitative methylation‐specific PCR technique. A questionnaire interview was conducted among the study participants to collect data on possible epigenetic modifiers. Additionally, the methylation profile was compared between three human mast cell lines: ROSA KIT D816V, ROSA KIT WT, and HMC‐1.1 KIT V560G, in order to assess the association between KIT mutations and methylation profile.ResultsA significantly lower level of DNA hydroxymethylation (5‐hmC) in the blood was found in patients with ISM as compared to the controls (0.022% vs. 0.042%, p = 0.0001). Differences in the markers of global DNA methylation (5‐mC, Alu, LINE‐1) were not statistically significant, although they did indicate generally higher DNA methylation in patients with mastocytosis. The 5‐hmC level was significantly associated with allergy (p = 0.011) in patients with ISM, showing a higher level of 5‐hmC in patients with allergy as compared to patients without allergy. The in vitro study revealed significant differences between the studied cell lines at the level of 5‐mC, Alu, and LINE‐1.ConclusionsThis study confirms that epigenetic changes are involved in mastocytosis, and suggests that allergy may be an important epigenetic modifier of the disease. A possible association between KIT mutations and methylation status observed in human mast cell lines requires further investigation in human studies.Clinical ImplicationsEpigenetic alterations are involved in mastocytosis pathology. The possible role of allergy as an important epigenetic modifier suggests the more impaired function of mast cells in ISM patients without allergy.Capsule summaryDecreased DNA demethylation in the blood DNA of patients with ISM confirms that epigenetic alterations are involved in mastocytosis pathology. We observed a possible role of allergy as an important epigenetic modifier. There is a possible association between KIT mutations and the methylation status observed in human mast cell lines. 相似文献
1000.
Sylwia Stpniewska Grayna Cacak-Pietrzak Anna Szafraska Ewa Ostrowska-Ligza Dariusz Dziki 《Materials》2021,14(24)
The properties of the starch-amylolytic complex of commercial low-extract rye flour were determined based on the traditional method, such as falling number and amylograph test as well as differential scanning calorimetry (DSC). The starch, pentosans and protein had a significant effect on the thermal properties of the tested rye flours. Based on the falling number, it was revealed that rye flours were characterized by medium and low alpha-amylase activity. The falling number and amylograph test are not sufficient methods to determine the suitability of currently produced rye flours for bread making. The gelatinization process of the rye flour starch could be evaluated by the DSC test, which, together with the falling number and amylograph test, may allow a better way to evaluate the usefulness of rye flours for bread making. Many significant correlations between parameters determined by DSC endotherm and quality parameters of rye bread, such as volume and crumb hardness, were reported. Breads made from flour with higher enthalpy in DSC were characterized by higher volume and softer crumb. 相似文献