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1.
Sci Rep ; 14(1): 13139, 2024 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849394

RESUMO

The enzyme dUTPase has an essential role in maintaining genomic integrity. In mouse, nuclear and mitochondrial isoforms of the enzyme have been described. Here we present the isoform-specific mRNA expression levels in different murine organs during development using RT-qPCR. In this study, we analyzed organs of 14.5-day embryos and of postnatal 2-, 4-, 10-week- and 13-month-old mice. We demonstrate organ-, sex- and developmental stage-specific differences in the mRNA expression levels of both isoforms. We found high mRNA expression level of the nuclear isoform in the embryo brain, and the expression level remained relatively high in the adult brain as well. This was surprising, since dUTPase is known to play an important role in proliferating cells, and mass production of neural cells is completed by adulthood. Thus, we investigated the pattern of the dUTPase protein expression specifically in the adult brain with immunostaining and found that dUTPase is present in the germinative zones, the subventricular and the subgranular zones, where neurogenesis occurs and in the rostral migratory stream where neuroblasts migrate to the olfactory bulb. These novel findings suggest that dUTPase may have a role in cell differentiation and indicate that accurate dTTP biosynthesis can be vital, especially in neurogenesis.


Assuntos
Encéfalo , Neurogênese , Pirofosfatases , Animais , Pirofosfatases/metabolismo , Pirofosfatases/genética , Camundongos , Feminino , Masculino , Encéfalo/metabolismo , Encéfalo/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Plants (Basel) ; 12(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37653906

RESUMO

Climate change may strongly modify the habitat conditions for many woody plant species. Some species could disappear from their natural habitats and become endangered, while others could adapt well to the changed environmental conditions and continue to survive successfully or even proliferate more easily. A similar process can occur within the artificial urban environment as the hitherto popularly planted urban trees may suffer from the extremities of the urban climate. However, among the planted taxa, there are species that spread spontaneously and appear as weeds in extensively managed gardens. In our study, we evaluated the native and non-native species involved in spontaneous spreading in the institutional garden of Buda Arboretum (Budapest) during the COVID-19 period in 2020-2021 when entry was prohibited, and maintenance went on in a restricted, minimal level. We investigated the correlation between spontaneously settling and planted individuals, and then performed multivariate analyses for native and non-native spreading plants for spatial and quantitative data. During our studies, we observed the spontaneous spreading of 114 woody species, of which 38 are native and 76 are non-native. Taking the total number of individuals into account, we found that, in addition to the 2653 woody species planted, a further 7087 spontaneously emerged weeds developed, which creates an additional task in the maintenance.

3.
Pharmaceutics ; 15(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37765225

RESUMO

Aceclofenac-loaded polyvinylpyrrolidone fiber-based amorphous solid dispersion was produced successfully by centrifugal spinning. The solution concentration and rotational speed were optimized to produce the fiber-based drug carrier system, with a determined production rate of 12.7 g/h dry solid fibers. The obtained fibers were bead-free and smooth-surfaced with an average diameter of 7.5 ± 2.5 µm. Gas chromatographic determinations revealed that ethanol, as a residual solvent, was well below the regulatory limit of 0.5%. Differential scanning calorimetric investigation and infrared spectroscopic measurements were used to track the physicochemical changes that intervene during fiber formation in the solid state. The results revealed that the rapid evaporation of the solvent was accompanied by a probable crystalline to amorphous transition of the active substance during centrifugal spinning. In vitro dissolution studies revealed an instantaneous disintegration of the fibrous structure and a rapid release of the active substance, with the microfibrous webs greatly outperforming the crystalline active substance, especially in the early time-points. This implies that centrifugal spinning offers a viable scale-up production process to prepare drug-loaded fiber-based solid dispersions.

4.
Sensors (Basel) ; 23(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37766023

RESUMO

Advanced vehicle-to-everything (V2X) safety applications must operate with ultra-low latency and be highly reliable. Therefore, they require sophisticated supporting technologies. This is especially true for cooperative applications, such as Collective Perception (CP), where a large amount of data constantly flows among vehicles and between vehicles and a network intelligence server. Both low and high-level support is needed for such an operation, meaning that various access technologies and other architectural elements also need to incorporate features enabling the effective use of V2X applications with strict requirements. The new 5G core architecture promises even more supporting technologies, like Multi-access Edge Computing (MEC). To test the performance of these technologies, an integrated framework for V2X simulations with 5G network elements is proposed in the form of combining Simu5G, a standalone 5G implementation, with the go-to V2X-simulator, Artery. As a first step toward a fully functional MEC-assisted CP Service, an extension to Simu5G's edge implementation is introduced. The edge application is responsible for dispatching the Collective Perception Messages generated by the vehicles via the 5G connectivity so that a MEC server provided by the network can process incoming data. Simulation results prove the operability of the proposed integrated system and edge computing's potential in assisting V2X scenarios.

5.
Polymers (Basel) ; 15(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37631425

RESUMO

Fibrous structures are promising candidates for oil-water separation applications. In this study, we have produced poly(styrene-b-isobutylene-b-styrene) thermoplastic elastomeric fibers with the centrifugal spinning fiber production method. The optimal fiber production conditions were achieved when using a 25% w/w solution concentration in an 80/20 tetrahydrofuran/toluene (w/w) solvent system at 8000 rpm rotational speed. The produced fibers were bead-free and smooth-surfaced with a diameter of 3.68 µm. The produced fibers were highly hydrophobic and oleophilic, suggested by a water contact angle of 129° and the instantaneous absorption of the oil droplet. The oil absorption study showed fast absorption kinetics with 94% relative oil uptake after 1 min and a maximum of 16.5 g sunflower oil/g fiber. The results suggest that polyisobutylene-based thermoplastic elastomers could be promising alternatives in oil absorption applications.

6.
Sci Rep ; 13(1): 7760, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173337

RESUMO

In human cells two dUTPase isoforms have been described: one nuclear (DUT-N) and one mitochondrial (DUT-M), with cognate localization signals. In contrast, here we identified two additional isoforms; DUT-3 without any localization signal and DUT-4 with the same nuclear localization signal as DUT-N. Based on an RT-qPCR method for simultaneous isoform-specific quantification we analysed the relative expression patterns in 20 human cell lines of highly different origins. We found that the DUT-N isoform is expressed by far at the highest level, followed by the DUT-M and the DUT-3 isoform. A strong correlation between expression levels of DUT-M and DUT-3 suggests that these two isoforms may share the same promoter. We analysed the effect of serum starvation on the expression of dUTPase isoforms compared to non-treated cells and found that the mRNA levels of DUT-N decreased in A-549 and MDA-MB-231 cells, but not in HeLa cells. Surprisingly, upon serum starvation DUT-M and DUT-3 showed a significant increase in the expression, while the expression level of the DUT-4 isoform did not show any changes. Taken together our results indicate that the cellular dUTPase supply may also be provided in the cytoplasm and starvation stress induced expression changes are cell line dependent.


Assuntos
Núcleo Celular , Mitocôndrias , Humanos , Células HeLa , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Pirofosfatases/genética , Pirofosfatases/metabolismo
7.
Polymers (Basel) ; 16(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38201788

RESUMO

An amorphous fiber-based solid dispersion of chlorzoxazone was prepared for the first time by employing centrifugal spinning, using polyvinylpyrrolidone as the fiber-forming polymer. After optimization of the spinning parameters, the obtained fibers were characterized using a set of analytical techniques, both in a solid- and solution-state. Morphological characterization revealed a slightly aligned, defect-free fibrous structure with an average fiber diameter of d = 3.07 ± 1.32 µm. The differential scanning calorimetric results indicated a crystalline-to-amorphous transition of the active substance during the centrifugal spinning process, while gas chromatographic determinations revealed a residual ethanol content of 0.42 ± 0.04%. UV spectroscopy indicated the incorporation of chlorzoxazone in the fibrous structures, with an average active substance content of 15.91 ± 0.36 w/w%. During small-volume dissolution studies, the prepared fiber mats presented immediate disintegration upon contact with the dissolution media, followed by rapid dissolution of the active substance, with 84.8% dissolved at 1 min and 93.7% at 3 min, outperforming the micronized, pure chlorzoxazone. The obtained results indicate that centrifugal spinning is a low-cost, high-yield, viable alternative to the currently used methods to prepare fiber-based amorphous solid dispersions of poorly soluble drugs. The prepared chlorzoxazone-loaded microfibers could be used as a buccal dosage form for the systematic delivery of chlorzoxazone and could potentially lead to a rapid onset of action and longer efficacy of the muscle relaxant drug.

8.
Polymers (Basel) ; 14(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36559924

RESUMO

Lapatinib (Lap) is a lypophilic drug frequently used in cancer treatment; however, due to its limited solubility and permeability, achieving therapeutic dose through oral administration proves to be a challenge. There are various methods for enhancing the solubility of Lap and other similar drugs, one being the preparation of amorphous solid dispersions (ASD). In this study, a Lap-loaded polyvinylpyrrolidone (PVP) fiber mat was created with centrifugal spinning from a PVP/Lap solution in dimethyl formamide and ethanol. The production rate was 12.2 g/h dry fibers, and the fibers had an average thickness of 2.55 ± 0.92 µm. In the differential scanning calorimetry (DSC) thermogram of the fiber mat, the melting peak of the crystalline Lap was not visible, suggesting that Lap was in an amorphous state. A dissolution study was carried out in 0.2 M phosphate buffer saline solution at 37 °C. UV spectrophotometry data indicated that in the sample containing the fiber mat, the Lap concentration was 332 µg/mL (66%) in 10 min, decreasing to 227 µg/mL by 45 min. Meanwhile the crystalline Lap formed a 30-40 µg/mL (6-8%) solution in 5 min, maintaining that concentration. We conclude that centrifugal spinning can be an effective and easy method to produce ASDs.

9.
Sci Rep ; 11(1): 19459, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593877

RESUMO

Reverse transcription-quantitative real-time PCR (RT-qPCR) is a ubiquitously used method in biological research, however, finding appropriate reference genes for normalization is challenging. We aimed to identify genes characterized with low expression variability among human cancer and normal cell lines. For this purpose, we investigated the expression of 12 candidate reference genes in 13 widely used human cancer cell lines (HeLa, MCF-7, A-549, K-562, HL-60(TB), HT-29, MDA-MB-231, HCT 116, U-937, SH-SY5Y, U-251MG, MOLT-4 and RPMI-8226) and, in addition, 7 normal cell lines (HEK293, MRC-5, HUVEC/TERT2, HMEC, HFF-1, HUES 9, XCL-1). In our set of genes, we included SNW1 and CNOT4 as novel candidate reference genes based on the RNA HPA cell line gene data from The Human Protein Atlas. HNRNPL and PCBP1 were also included along with the "classical" reference genes ACTB, GAPDH, IPO8, PPIA, PUM1, RPL30, TBP and UBC. Results were evaluated using GeNorm, NormFiner, BestKeeper and the Comparative ΔCt methods. In conclusion, we propose IPO8, PUM1, HNRNPL, SNW1 and CNOT4 as stable reference genes for comparing gene expression between different cell lines. CNOT4 was also the most stable gene upon serum starvation.


Assuntos
Perfilação da Expressão Gênica/normas , Reação em Cadeia da Polimerase em Tempo Real/normas , Linhagem Celular , Linhagem Celular Tumoral , Perfilação da Expressão Gênica/métodos , Humanos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Padrões de Referência , Reprodutibilidade dos Testes
10.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206377

RESUMO

Infiltration of red blood cells into atheromatous plaques and oxidation of hemoglobin (Hb) and lipoproteins are implicated in the pathogenesis of atherosclerosis. α1-microglobulin (A1M) is a radical-scavenging and heme-binding protein. In this work, we examined the origin and role of A1M in human atherosclerotic lesions. Using immunohistochemistry, we observed a significant A1M immunoreactivity in atheromas and hemorrhaged plaques of carotid arteries in smooth muscle cells (SMCs) and macrophages. The most prominent expression was detected in macrophages of organized hemorrhage. To reveal a possible inducer of A1M expression in ruptured lesions, we exposed aortic endothelial cells (ECs), SMCs and macrophages to heme, Oxy- and FerrylHb. Both heme and FerrylHb, but not OxyHb, upregulated A1M mRNA expression in all cell types. Importantly, only FerrylHb induced A1M protein secretion in aortic ECs, SMCs and macrophages. To assess the possible function of A1M in ruptured lesions, we analyzed Hb oxidation and heme-catalyzed lipid peroxidation in the presence of A1M. We showed that recombinant A1M markedly inhibited Hb oxidation and heme-driven oxidative modification of low-density lipoproteins as well plaque lipids derived from atheromas. These results demonstrate the presence of A1M in atherosclerotic plaques and suggest its induction by heme and FerrylHb in the resident cells.


Assuntos
alfa-Globulinas/metabolismo , Aterosclerose/etiologia , Aterosclerose/metabolismo , Heme/metabolismo , Hemoglobinas/metabolismo , Peroxidação de Lipídeos , Oxirredução , Aterosclerose/patologia , Biomarcadores , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Células Cultivadas , Progressão da Doença , Suscetibilidade a Doenças , Hemorragia/metabolismo , Hemorragia/patologia , Humanos , Imuno-Histoquímica , Miócitos de Músculo Liso/metabolismo , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia
11.
Sci Rep ; 10(1): 21305, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33277528

RESUMO

Oscillation and collective behavior of diffusion flames is a fascinating phenomena. Considering candle bundles with different sizes in variable oxygen concentration, the flickering dynamics of the flames are experimentally and theoretically investigated. Trends for the flickering frequency as a function of the candle number in the bundle and oxygen concentration is revealed for various topologies of the candles packing. The collective behavior of the flames as a function of their separation distance is studied by measuring an appropriate synchronization order parameter and through the common oscillation frequency. In agreement with previous results we find a discontinuous phase transition between an in-phase synchronized state at small separation distance and a counter-phase synchronized state at larger separation distances. A previously used dynamical model is modified in order to accommodate our experimental findings.

12.
Pharmaceutics ; 12(7)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629988

RESUMO

Fenofibrate-loaded electrospun microfibrous sheets were prepared in an attempt to enhance the dissolution of the poorly soluble antihyperlipidemic agent and to improve its bioavailability. Physicochemical changes that appeared during the electrospinning process were monitored using a wide array of solid-state characterization techniques, including attenuated total reflectance Fourier-transformed infrared spectroscopy and positron annihilation lifetime spectroscopy, while fiber morphology was monitored via scanning electron microscopy. Dissolution studies carried out both in 0.025 M sodium dodecyl sulfate and in water revealed an immediate release of the active agent, with an approximately 40-fold release rate enhancement in water when compared to the micronized active agent. The dramatic increase in dissolution was attributed partially to the amorphous form of the originally crystalline active agent and the rapid disintegration of the electrospun microfibrous sheet due to its high surface area and porosity. The obtained results could pave the way for a formulation of the frequently used antihyperlipidemic agent with increased bioavailability.

13.
Biomolecules ; 9(4)2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987342

RESUMO

Sanitization of nucleotide pools is essential for genome maintenance. Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) is a key enzyme in this pathway since it catalyzes the cleavage of 2'-deoxyuridine 5'-triphosphate (dUTP) into 2'-deoxyuridine 5'-monophosphate (dUMP) and inorganic pyrophosphate. Through its action dUTPase efficiently prevents uracil misincorporation into DNA and at the same time provides dUMP, the substrate for de novo thymidylate biosynthesis. Despite its physiological significance, knock-out models of dUTPase have not yet been investigated in mammals, but only in unicellular organisms, such as bacteria and yeast. Here we generate CRISPR/Cas9-mediated dUTPase knock-out in mice. We find that heterozygous dut +/- animals are viable while having decreased dUTPase levels. Importantly, we show that dUTPase is essential for embryonic development since early dut -/- embryos reach the blastocyst stage, however, they die shortly after implantation. Analysis of pre-implantation embryos indicates perturbed growth of both inner cell mass (ICM) and trophectoderm (TE). We conclude that dUTPase is indispensable for post-implantation development in mice.


Assuntos
Desenvolvimento Embrionário/genética , Deleção de Genes , Pirofosfatases/genética , Animais , Blastocisto/metabolismo , Blastocisto/patologia , Sistemas CRISPR-Cas , Células Cultivadas , Heterozigoto , Homozigoto , Camundongos , Camundongos Knockout , Pirofosfatases/metabolismo
14.
Acta Microbiol Immunol Hung ; 63(4): 373-385, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28166641

RESUMO

Cells of the immune system synthesize, store, and secrete polypeptide and amino acid type hormones, which also influence their functions, having receptors for different hormones. In the present experiment immunophenotyped immune cells isolated from bone marrow, thymus, and peritoneal fluid of mice were used for demonstrating the adrenocorticotropic hormone (ACTH) and triiodothyronine (T3) hormone production of differentiating immune cells. Both hormones were found in each cell type, and in each maturation state, which means that all cells are participating in the hormonal function of the immune system. The lineage-independent presence of ACTH and T3 in differentiating hematopoietic cells denotes that their expression ubiquitous during lymphocyte development. Higher ACTH and T3 content of B cells shows that these cells are the most hormonally active and suggests that the hormones may have an autocrine regulatory role in B cell development. Developing T cells showed heterogeneous hormone production which was associated with their maturation state. Differences in the hormone contents of immune cells isolated from different organs indicate that their hormone production is defined by their differentiation or maturation state, however, possibly also by the local microenvironment.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Linfócitos/metabolismo , Tri-Iodotironina/metabolismo , Animais , Células Cultivadas , Citometria de Fluxo , Subpopulações de Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C
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