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1.
Int J Mol Sci ; 25(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38256067

RESUMO

Anemonopsis Siebold et Zucc. is an unstudied single-species genus belonging to the tribe Cimicifugeae (Ranunculaceae). The only species of this genus-Anemonopsis macrophylla Siebold and Zucc.-is endemic to Japan. There are no data on its chemical composition. This work is the first to determine (with liquid chromatography-high-resolution mass spectrometry, LC-HRMS) the chemical composition of methanol extracts of leaves and flowers of A. macrophylla. More than 100 compounds were identified. In this plant, the classes of substances are coumarins (13 compounds), furocoumarins (3), furochromones (2), phenolic acids (21), flavonoids (27), and fatty acids and their derivatives (15 compounds). Isoferulic acid (detected in extracts from this plant) brings this species closer to plants of the genus Cimicifuga, one of the few genera containing this acid and ferulic acid at the same time. Isoferulic acid is regarded as a reference component of a quality indicator of Cimicifuga raw materials. The determined profiles of substances are identical between the leaf and flower methanol extracts. Differences in levels of some identified substances were revealed between the leaf and flower extracts of A. macrophylla; these differences may have a substantial impact on the manifestation of the biological and pharmacological effects of the extracts in question.


Assuntos
Cinamatos , Ranunculaceae , Metanol , Folhas de Planta , Flores
2.
Int J Mol Sci ; 24(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36768793

RESUMO

Necrotizing enterocolitis (NEC) is a life-threatening disease that predominantly affects very low birth weight preterm infants. Development of NEC in preterm infants is accompanied by high mortality. Surgical treatment of NEC can be complicated by short bowel syndrome, intestinal failure, parenteral nutrition-associated liver disease, and neurodevelopmental delay. Issues surrounding pathogenesis, prevention, and treatment of NEC remain unclear. This review summarizes data on prenatal risk factors for NEC, the role of pre-eclampsia, and intrauterine growth retardation in the pathogenesis of NEC. The role of hypoxia in NEC is discussed. Recent data on the role of the intestinal microbiome in the development of NEC, and features of the metabolome that can serve as potential biomarkers, are presented. The Pseudomonadota phylum is known to be associated with NEC in preterm neonates, and the role of other bacteria and their metabolites in NEC pathogenesis is also discussed. The most promising approaches for preventing and treating NEC are summarized.


Assuntos
Enterocolite Necrosante , Microbioma Gastrointestinal , Doenças do Recém-Nascido , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Enterocolite Necrosante/etiologia , Retardo do Crescimento Fetal , Hipóxia
3.
Int J Mol Sci ; 24(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37762175

RESUMO

By means of liquid chromatography combined with high-resolution mass spectrometry, metabolite profiling was performed on an aqueous-ethanol extract from Spiraea hypericifolia (Rosaceae) collected in Siberia (Russia). Up to 140 compounds were found in the extract, of which 47 were tentatively identified. The identified compounds were amino acids, sugars, phenylpropanoids, fatty acids and their derivatives, triterpenoids, flavonoids, and others. A quantitative analysis showed the predominance of phenolcarboxylic acids and flavonoids in the studied extract, but a qualitative analysis revealed the higher structural diversity of flavonoids. Of the 23 identified flavonoids, 13 were flavonols: quercetin, hyperoside, isoquercitrin, reynoutrin, avicularin, rutin, quercetin-3-O-(6″-O-malonyl)-ß-D-glucoside, 3-O-methylquercetin-3'-O-ß-D-glucopyranoside, isorhamnetin, rhamnetin-3-O-ß-D-xylopyranosyl-ß-D-glucopyranoside, kaempferol, tiliroside, and trifolin; six were catechins: catechin, (-)-epicatechin, (+)-epicatechin, (+)-catechin-7-O-ß-D-xyloside, (2S,3R)-3,5-dihydroxy-2-(4-hydroxyphenyl)-3,4-dihydro-2H-chromen-7-yl-ß-D-glucopyranoside, and catechin 7-O-apiofuranoside; two are isoflavones: genistin and genistein; and one was a flavone (luteolin-4'-O-ß-D-glucopyranoside) and another was an anthocyanidin (pelargonidin). The aqueous-ethanol extract from S. hypericifolia showed antioxidant activity (half-maximal inhibitory concentration 102.95 µg/mL), which was likely related to the high concentrations of phenolcarboxylic acids (229.6 mg/g), flavonoids (118.3 mg/g), and tannins (62.9 mg/g).


Assuntos
Catequina , Rosaceae , Spiraea , Quercetina , Flavonoides , Extratos Vegetais/farmacologia
4.
Int J Mol Sci ; 24(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38003233

RESUMO

Trisomy is the presence of one extra copy of an entire chromosome or its part in a cell nucleus. In humans, autosomal trisomies are associated with severe developmental abnormalities leading to embryonic lethality, miscarriage or pronounced deviations of various organs and systems at birth. Trisomies are characterized by alterations in gene expression level, not exclusively on the trisomic chromosome, but throughout the genome. Here, we applied the high-throughput chromosome conformation capture technique (Hi-C) to study chromatin 3D structure in human chorion cells carrying either additional chromosome 13 (Patau syndrome) or chromosome 16 and in cultured fibroblasts with extra chromosome 18 (Edwards syndrome). The presence of extra chromosomes results in systematic changes of contact frequencies between small and large chromosomes. Analyzing the behavior of individual chromosomes, we found that a limited number of chromosomes change their contact patterns stochastically in trisomic cells and that it could be associated with lamina-associated domains (LAD) and gene content. For trisomy 13 and 18, but not for trisomy 16, the proportion of compacted loci on a chromosome is correlated with LAD content. We also found that regions of the genome that become more compact in trisomic cells are enriched in housekeeping genes, indicating a possible decrease in chromatin accessibility and transcription level of these genes. These results provide a framework for understanding the mechanisms of pan-genome transcription dysregulation in trisomies in the context of chromatin spatial organization.


Assuntos
Núcleo Celular , Trissomia , Recém-Nascido , Humanos , Trissomia/genética , Núcleo Celular/metabolismo , Cromatina/genética , Cromatina/metabolismo , Testes Genéticos , Síndrome da Trissomia do Cromossomo 13/genética
5.
Magn Reson Med ; 87(6): 2914-2921, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35014736

RESUMO

PURPOSE: Validation of quantitative MR measures for myelin imaging in the postmortem multiple sclerosis spinal cord. METHODS: Four fixed spinal cord samples were imaged first with a 3T clinical MR scanner to identify areas of interest for scanning, and then with a 7T small bore scanner using a multicomponent-driven equilibrium single-pulse observation of T1 and T2 protocol to produce apparent proton density, T1 , T2 , myelin water, intracellular water, and free-water fraction maps. After imaging, the cords were sectioned and stained with histological markers (hematoxylin and eosin, myelin basic protein, and neurofilament protein), which were quantitatively compared with the MR maps. RESULTS: Excellent correspondence was found between high-resolution MR parameter maps and histology, particularly for apparent proton density MRI and myelin basic protein staining. CONCLUSION: High-resolution quantitative MRI of the spinal cord provides biologically meaningful measures, and could be beneficial to diagnose and track multiple sclerosis lesions in the spinal cord.


Assuntos
Esclerose Múltipla , Humanos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Proteína Básica da Mielina , Bainha de Mielina/patologia , Prótons , Medula Espinal/diagnóstico por imagem , Água
6.
Ann Neurol ; 88(3): 619-625, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32608018

RESUMO

Disability in multiple sclerosis (MS) is considered primarily a result of axonal loss. However, correlation with spinal cord cross-sectional area-a predictor of disability-is poor, questioning the unique role of axonal loss. We investigated the degree of synaptic loss in postmortem spinal cords (18 chronic MS, 8 healthy controls) using immunohistochemistry for synaptophysin and synapsin. Substantial (58-96%) loss of synapses throughout the spinal cord was detected, along with moderate (47%) loss of anterior horn neurons, notably in demyelinating MS lesions. We conclude that synaptic loss is significant in chronic MS, likely contributing to disability accrual. ANN NEUROL 2020;88:619-625.


Assuntos
Esclerose Múltipla/patologia , Medula Espinal/patologia , Sinapses/patologia , Idoso , Autopsia , Feminino , Humanos , Masculino
7.
Exp Brain Res ; 239(2): 627-638, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33388811

RESUMO

Localized carrier-mediated administration of drugs is a promising approach to treatment of acute phase of spinal cord injury (SCI) as it allows enhanced and/or sustained drug delivery to damaged tissues along with minimization of systemic side effects. We studied the effect of locally applied self-assembling micellar formulation of methylprednisolone succinate (MPS) with trifunctional block copolymer of ethylene oxide and propylene oxide (TBC) on functional recovery and tissue drug content after SCI in rats in comparison with local and systemic administration of MPS alone. Variations in the amplitude of motor evoked responses in the hindlimb muscles induced by epidural stimulation during acute phase of SCI and restoration of movements during chronic period after local vs. systemic application of MPS were evaluated in this study. Results demonstrate that local delivery of MPS in combination with TBC facilitates spinal cord sensorimotor circuitry, increasing the excitability. In addition, this formulation was found to be more effective in improvement of locomotion after SCI compared to systemic administration. LC-MS/MS data shows that the use of TBC carrier increases the glucocorticoid content in treated spinal cord by more than four times over other modes of treatment. The results of this study demonstrate that the local treatment of acute SCI with MPS in the form of mixed micelles with TBC can provide improved therapeutic outcome by promoting drug accumulation and functional restoration of the spinal cord.


Assuntos
Hemissuccinato de Metilprednisolona , Traumatismos da Medula Espinal , Animais , Cromatografia Líquida , Ratos , Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Espectrometria de Massas em Tandem
8.
Nucleic Acids Res ; 47(13): 6811-6825, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31114877

RESUMO

The contribution of nucleoli to the cellular stress response has been discussed for over a decade. Stress-induced inhibition of RNA polymerase I-dependent transcription is hypothesized as a possible effector program in such a response. In this study, we report a new mechanism by which ribosomal DNA transcription can be inhibited in response to cellular stress. Specifically, we demonstrate that mild hypoosmotic stress induces stabilization of R loops in ribosomal genes and thus provokes the nucleoli-specific DNA damage response, which is governed by the ATM- and Rad3-related (ATR) kinase. Activation of ATR in nucleoli strongly depends on Treacle, which is needed for efficient recruitment/retention of TopBP1 in nucleoli. Subsequent ATR-mediated activation of ATM results in repression of nucleolar transcription.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/fisiologia , Proteínas de Transporte/genética , Nucléolo Celular/metabolismo , DNA Ribossômico/genética , Proteínas de Ligação a DNA/genética , Inativação Gênica , Proteínas Nucleares/genética , Pressão Osmótica , Estruturas R-Loop , Transcrição Gênica/fisiologia , Animais , Linhagem Celular , Nucléolo Celular/efeitos dos fármacos , Sobrevivência Celular , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Replicação do DNA , Dactinomicina/farmacologia , Ativação Enzimática/efeitos dos fármacos , Técnicas de Inativação de Genes , Histonas/metabolismo , Humanos , Soluções Hipotônicas/farmacologia , Camundongos , Proteínas Nucleares/fisiologia , Fosfoproteínas/fisiologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos
9.
Int J Mol Sci ; 22(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34681821

RESUMO

The genus Spiraea L. belongs to the Rosaceae Juss. family and includes more than 100 species distributed in the temperate zone and subtropical zone of the Northern Hemisphere at the center of species diversity in East Asia. Representatives of the genus are known as ornamental plants with many forms and varieties, are widely used in conventional medicine, and have a high resource potential. This review provides information on the diversity of phenolic compounds (flavonoids, phenolcarboxylic acids, and lignans), terpenoids, alkaloids, steroids, and other classes of secondary metabolites in the species of Spiraea worldwide. The article also presents little-known and hard-to-find data published in Russian concerning Spiraea phytochemistry. The biological activities of extracts and their fractions and of individual compounds having different types of biological activity (e.g., antioxidant, antibacterial, anti-inflammatory, and antifungal) are discussed. Data about biotechnological research on representatives of the genus Spiraea are presented too. The analysis of the literature showed that further chemical and pharmacological studies on Spiraea plants are quite promising.


Assuntos
Medicina Tradicional , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Spiraea/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Técnicas de Cultura de Células , Ásia Oriental , Humanos
10.
Int J Mol Sci ; 23(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35008829

RESUMO

Aqueous-ethanol extracts (70%) from the leaves of Eranthis longistipitata Regel. (Ranunculaceae Juss.)-collected from natural populations of Kyrgyzstan-were studied by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). There was no variation of the metabolic profiles among plants that were collected from different populations. More than 160 compounds were found in the leaves, of which 72 were identified to the class level and 58 to the individual-compound level. The class of flavonoids proved to be the most widely represented (19 compounds), including six aglycones [quercetin, kaempferol, aromadendrin, 6-methoxytaxifolin, phloretin, and (+)-catechin] and mono- and diglycosides (the other 13 compounds). In the analyzed samples of E. longistipitata, 14 fatty acid-related compounds were identified, but coumarins and furochromones that were found in E. longistipitata were the most interesting result; furochromones khelloside, khellin, visnagin, and cimifugin were found in E. longistipitata for the first time. Coumarins 5,7-dihydroxy-4-methylcoumarin, scoparone, fraxetin, and luvangetin and furochromones methoxsalen, 5-O-methylvisammioside, and visamminol-3'-O-glucoside were detected for the first time in the genus Eranthis Salisb. For all the above compounds, the structural formulas are given. Furthermore, detailed information (with structural formulas) is provided on the diversity of chromones and furochromones in other representatives of Eranthis. The presence of chromones in plants of the genus Eranthis confirms its closeness to the genus Actaea L. because chromones are synthesized by normal physiological processes only in these members of the Ranunculaceae family.


Assuntos
Cromonas/análise , Cumarínicos/análise , Compostos Fitoquímicos/análise , Ranunculaceae/química , Cromatografia Líquida , Cromonas/química , Cumarínicos/química , Espectrometria de Massas , Compostos Fitoquímicos/química
11.
Molecules ; 26(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557189

RESUMO

The physical and mechanical properties of nitrile-butadiene rubber (NBR) composites with N-cetylpyridinium bromide-carbon black (CPB-CB) were investigated. Addition of 5 parts per hundred rubber (phr) of CPB-CB into NBR improved the tensile strength by 124%, vulcanization rate by 41%, shore hardness by 15%, and decreased the volumetric wear by 7% compared to those of the base rubber-CB composite.


Assuntos
Butadienos/química , Cetilpiridínio/química , Fenômenos Mecânicos , Nitrilas/química , Fenômenos Físicos , Borracha/química , Fuligem/química
12.
Psychiatr Danub ; 32(Suppl 1): 88-92, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32890370

RESUMO

BACKGROUND: The present study reports preliminary results from the multicentre project on the approbation of the Russian language version of the "The Communication Checklist-Self Report" (RL-CC-SR) and its first use in schizophrenia (SZ), aiming to evaluate the contribution of language disturbances in the pathogenesis of this heterogeneous disorder. SUBJECTS AND METHODS: The study evaluated patients' clinical state with the Diagnostic Interview for Psychoses (DIP), and assessed language and communication disturbances (LCD) with the RL-CC-SR in all participants (213 healthy controls (HC), 83 SZ patients, 31 SZ first-degree relatives). Data from the current sample of SZ (n=50), and HC (n=213) was analysed to calculate the relationships between LCD, social and clinical variables using descriptive statistics methods, T-test and Pearson's correlations (SPSS-26, 2019). RESULTS: The quotient scores (<6) and raw scores on all three CC-SR subscales demonstrated prominent LCD in SZ: (i) language structure (LS) (SZ:11.92±8.01, HC:7.54±5.91; p<0.001), (ii) pragmatic skills (PS) (SZ:11.30±10.07, HC:8.71±7.39; p=0.040), (iii) social engagement (SE) (SZ:31.94±11.76, HC:19.42±10.35; p<0.001). In SZ, Pearson correlations of LS scores were significant for the DIP-items Odd Speech (p=0.033), and Social Engagement - Blunted Affect (p=0.042). PS was related to early disease onset (p=0.027), poor premorbid work adjustment (p=0.003), along with LS (p=0.005), and was also linked to poor premorbid social adjustment (p=0.005). CONCLUSIONS: SZ patients are aware of their LCD at all levels of language structure, pragmatics, and nonverbal communication, but are unable to compensate. Disturbances of LS and PS in SZ patients relate to their poor social adjustment and functioning, and may prove to be associated with the primary negative symptoms domain of the disorder and its generally poor outcome.


Assuntos
Lista de Checagem , Transtornos do Desenvolvimento da Linguagem , Esquizofrenia , Autorrelato , Humanos , Transtornos do Desenvolvimento da Linguagem/etiologia , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Ajustamento Social
13.
Eur Biophys J ; 48(1): 25-34, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30105402

RESUMO

Chemical modification of therapeutic peptides is an important approach to improving their physicochemical and pharmacokinetic properties. The triphenylphosphonium (TPP) cation has proved to be a powerful modifier; however, its effects on peptide structure and activity remain uncharacterized. In this study, cytoprotective tetrapeptides based on the YRFK opioid motif with L- or D-Arg residues were linked to (triphenylphosphonio)carboxylic acids with ethylene and pentylene spacers (TPP-3 and TPP-6 groups, respectively). The three-dimensional structure of the oligopeptides was analyzed by NMR spectroscopy, computational methods and circular dichroism (CD). A more compact and bent structure with segregated aromatic groups was revealed for the D-arginine-containing tetrapeptide and its TPP-6 derivative. The TPP moiety caused structure-organizing effect on the tetrapeptides, resulting in transition from random coil to ß-sheet structures, and decreased the peptide backbone flexibility up to ten times. The TPP-3-modified oligopeptide with the lowest RMSD value (ca. 0.05 Å) was characterized by intrapeptide hydrophobic interactions between the TPP and side groups of Tyr and Phe residues accompanied by strong CD induction. The TPP-6-modified oligopeptides showed enhanced ability to form intermolecular associates and disturb liposomal membranes. The relationship between the spatial structure of the oligopeptides and some of their biologically relevant interactions were additionally revealed and are discussed.


Assuntos
Oligopeptídeos/química , Compostos Organofosforados/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Modelos Moleculares , Estereoisomerismo
14.
Mol Biol Evol ; 34(6): 1492-1504, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333290

RESUMO

The genomes are folded in a complex three-dimensional (3D) structure. Some features of this organization are common for all eukaryotes, but little is known about its evolution. Here, we have studied the 3D organization and regulation of zebrafish globin gene domain and compared its organization and regulation with those of other vertebrate species. In birds and mammals, the α- and ß-globin genes are segregated into separate clusters located on different chromosomes and organized into chromatin domains of different types, whereas in cold-blooded vertebrates, including Danio rerio, α- and ß-globin genes are organized into common clusters. The major globin gene locus of Danio rerio is of particular interest as it is located in a genomic area that is syntenic in vertebrates and is controlled by a conserved enhancer. We have found that the major globin gene locus of Danio rerio is structurally and functionally segregated into two spatially distinct subloci harboring either adult or embryo-larval globin genes. These subloci demonstrate different organization at the level of chromatin domains and different modes of spatial organization, which appears to be due to selective interaction of the upstream enhancer with the sublocus harboring globin genes of the adult type. These data are discussed in terms of evolution of linear and 3D organization of gene clusters in vertebrates.


Assuntos
Cromatina/genética , Globinas/genética , Conformação Molecular , Animais , Evolução Biológica , Aves/genética , Cromossomos/genética , Evolução Molecular , Genoma , Mamíferos/genética , Família Multigênica/genética , Peixe-Zebra/genética , alfa-Globinas/genética , Globinas beta/genética
15.
Int Arch Allergy Immunol ; 175(4): 246-251, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29566383

RESUMO

BACKGROUND/AIM: In chronic spontaneous urticaria (CSU), Helicobacter pylori (HP) has been discussed as a cause, but it is unknown whether the bacterium itself or concomitant inflammation is causing the urticaria. Our aim was to investigate HP and upper gastrointestinal lesions as signs of inflammation independently of each other in the pathogenesis of CSU. METHODS: A total of 36 prospectively enrolled CSU patients from Moscow were investigated by gastroscopy and screened for the presence of HP and/or upper gastrointestinal lesions. Those having a positive result were treated according to the Maastricht III recommended guidelines for eradication therapy, and success was assessed by a follow-up gastroscopy. Simultaneously, the activity of CSU was measured before and after therapy of the gastrointestinal condition. RESULTS: HP was observed in 26 of the 36 patients. Erosions or ulcers were found in 18 of the 36 patients, 14 of whom were also positively tested for HP. There was a significant difference in improvement of urticarial symptoms between those who succeeded in healing the erosions and those who did not succeed (p < 0.01) independent of the presence of HP. No significant difference in symptom relief was observed between those who had successful eradication and those in whom HP eradication failed. CONCLUSIONS: Upper gastrointestinal inflammatory disorders can cause CSU and trigger exacerbations independently of HP. This might imply that also in HP-positive patients, urticaria is not based on an immunological reaction against the germ but rather on the underlying inflammation. These findings also strengthen the importance of a gastroenterological workup of patients with CSU.


Assuntos
Gastrite/complicações , Urticária/etiologia , Adulto , Idoso , Doença Crônica , Feminino , Gastrite/microbiologia , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Molecules ; 23(9)2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150557

RESUMO

Sealing rubbers employed in cold climates such as the Siberian Arctic must be able to withstand temperatures as low as -50 °C while still exhibiting specific relaxation, strength, tribological characteristics, and a resistance to aggressive media. Previous investigations of propylene oxide rubber (SKPO, Tg = -73 °C) modified with polytetrafluoroethylene (PTFE) have revealed that, while the rubber composite materials exhibit double the wear resistance compared to unmodified polypropylene oxide rubber, they have poor frost resistance. In the present study, we developed materials based on SKPO and ultrafine PTFE (UPTFE), which can be characterized by its smaller particle size, low molecular weight, high tribo-technical characteristics, and resistance to aggressive media. The properties of the rubber composites were evaluated using the standard methods. The structures of the materials were investigated by electron microscopy and XRD analysis. It was shown that the materials have excellent wear resistance, resistance to aggressive media, compression set, and low-temperature resistance. The addition of UPTFE is preferable to the addition of PTFE because the desired positive effects can be attained with only 0.5⁻1 parts per hundred parts of rubber (phr) UPTFE while 20 phr PTFE would be necessary.


Assuntos
Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Borracha/química , Teste de Materiais , Fenômenos Mecânicos , Difração de Raios X
17.
Histochem Cell Biol ; 145(4): 463-73, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26847176

RESUMO

In Danio rerio, the alpha- and beta-globin genes are present in two clusters: a major cluster located on chromosome 3 and a minor cluster located on chromosome 12. In contrast to the segregated alpha- and beta-globin gene domains of warm-blooded animals, in Danio rerio, each cluster contains both alpha- and beta-globin genes. Expression of globin genes present in the major cluster is controlled by an erythroid-specific enhancer similar to the major regulatory element of mammalian and avian alpha-globin gene domains. The enhancer controlling expression of the globin genes present in the minor locus has not been identified yet. Based on the distribution of epigenetic marks, we have selected two genomic regions that might harbor an enhancer of the minor locus. Using transient transfection of constructs with a reporter gene, we have demonstrated that a ~500-bp DNA fragment located ~1.7 Kb upstream of the αe4 gene possesses an erythroid-specific enhancer active with respect to promoters present in both the major and the minor globin gene loci of Danio rerio. The identified enhancer element harbors clustered binding sites for GATA-1, NF-E2, and EKLF similar to the enhancer of the major globin locus on chromosome 3. Both enhancers appear to have emerged as a result of independent evolution of a duplicated regulatory element present in an ancestral single alpha-/beta-globin locus that existed before teleost-specific genome duplication.


Assuntos
Elementos Facilitadores Genéticos/genética , Peixe-Zebra/genética , alfa-Globinas/genética , Globinas beta/genética , Animais , Sítios de Ligação , Células Cultivadas , Embrião de Galinha , Galinhas
18.
Blood ; 123(13): 2044-53, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-24452204

RESUMO

In mantle cell lymphoma (MCL), one allele of the cyclin D1 (Ccnd1) gene is translocated from its normal localization on chromosome 11 to chromosome 14. This is considered as the crucial event in the transformation process of a normal naive B-cell; however, the actual molecular mechanism leading to Ccnd1 activation remains to be deciphered. Using a combination of three-dimensional and immuno-fluorescence in situ hybridization experiments, the radial position of the 2 Ccnd1 alleles was investigated in MCL-derived cell lines and malignant cells from affected patients. The translocated Ccnd1 allele was observed significantly more distant from the nuclear membrane than its nontranslocated counterpart, with a very high proportion of IgH-Ccnd1 chromosomal segments localized next to a nucleolus. These perinucleolar areas were found to contain active RNA polymerase II (PolII) clusters. Nucleoli are rich in nucleolin, a potent transcription factor that we found to bind sites within the Ccnd1 gene specifically in MCL cells and to activate Ccnd1 transcription. We propose that the Ccnd1 transcriptional activation in MCL cells relates to the repositioning of the rearranged IgH-Ccnd1-carrying chromosomal segment in a nuclear territory with abundant nucleolin and active PolII molecules. Similar transforming events could occur in Burkitt and other B-cell lymphomas.


Assuntos
Nucléolo Celular/metabolismo , Ciclina D1/metabolismo , Regulação Neoplásica da Expressão Gênica , Linfoma de Célula do Manto/genética , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ativação Transcricional , Transporte Ativo do Núcleo Celular/fisiologia , Fator de Ligação a CCCTC , Linhagem Celular Tumoral , Ciclina D1/genética , Genes Neoplásicos , Células HeLa , Humanos , Transporte Proteico , Proteínas Repressoras/metabolismo , Nucleolina
19.
J Sleep Res ; 24(3): 288-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25431234

RESUMO

The purpose of this work was to examine the relationships between geographical coordinates and the prevalence of winter depression (SADW ), and to compare the sleep characteristics and chronotype of youths with and without SADW . We conducted a cross-sectional study of self-reported sleep characteristics, chronotype and winter depression in northern European Russia. Two questionnaires, the Munich Chronotype Questionnaire (MCTQ) and the Seasonal Pattern Assessment Questionnaire (SPAQ), were administered to a total of 3435 adolescents aged 10-20 years (1517 males and 1918 females). The prevalence of SADW in the study population was 8.4% and sub-SADW 11.8%. Four variables predicted the likelihood of SADW in youths: sex [higher in females: odds ratio (OR): 1.87, P < 0.0001], age (increases with age: OR: 1.09, P < 0.001), latitude (higher in the North: OR: 1.49, P < 0.029) and position in the time zone (higher in the West: OR: 1.61, P < 0.001). Later sleeping and waking, longer sleep latencies, more severe sleep inertia, shorter total sleep times and lower sleep efficiencies were observed in both males and females with SADW . The influence of SADW on sleep characteristics was more pronounced on school days. Significant phase delays of the sleep-wake rhythm and severe social jetlag (the difference between the mid-point of sleep phase at weekends and on workdays) were observed in females with SADW , but not in males. There are significant differences in sleep characteristics and chronotype between people with SADW and no-SAD. We demonstrate that both latitude of residence and location within the time zone are significant predictors of SADW in young inhabitants of the North.


Assuntos
Ritmo Circadiano/fisiologia , Depressão/epidemiologia , Estações do Ano , Sono/fisiologia , Adolescente , Envelhecimento , Criança , Estudos Transversais , Depressão/fisiopatologia , Feminino , Humanos , Masculino , Federação Russa/epidemiologia , Autorrelato , Caracteres Sexuais , Transtornos do Sono do Ritmo Circadiano/epidemiologia , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Fases do Sono/fisiologia , Inquéritos e Questionários , Adulto Jovem
20.
Plants (Basel) ; 12(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38005692

RESUMO

This review summarizes information about the chemical composition and beneficial properties of species of the genus Eranthis Salisb. from the world's flora. To date, seven out of ~14 species found in Asia and parts of Europe have been studied to various degrees. Here, data are presented on the diversity of sets of chromones, furochromones, triterpene saponins, coumarins, and other classes of secondary metabolites of Eranthis species according to the literature. For new compounds-isolated from Eranthis for the first time-structural formulas are also provided. Among the new compounds, chromones and coumarins predominate, as do triterpene saponins of the olean and cycloartane series and lectin. The results of pharmacological studies are presented showing anti-inflammatory, antioxidant, antiviral, and other types of biological activities found in extracts, in their fractions, and in individual compounds of the aboveground and underground organs and parts of Eranthis species. Despite the limited geographic range of Eranthis plants, it is possible to search for active substances, develop methods for biological and chemical synthesis of the isolated substances, and create a finished therapeutic substance based on them. In addition, it is feasible to obtain the desired standardized pure materials from Eranthis species grown in vitro.

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