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1.
Materials (Basel) ; 16(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37512364

RESUMO

Chitosan is a natural biopolymer with a proven ability to impart textile materials with antimicrobial properties when loaded onto them. The mechanism of its bacteriological activity depends on the contact between the positive and negative charges of the amino groups located on the surface of the microbes. Unfortunately, the type of microorganisms and pH influence this action-shortcomings that can be avoided by chitosan modification and by loading its film with substances possessing antimicrobial properties. In this study, chitosan was modified with benzaldehyde and crosslinked with glutaraldehyde to form a film on the surface of cotton fabric (CB). Also, another material was obtained by including zinc oxide particles (CBZ) synthesized in situ into the chitosan coating. The performed analyses (contact angle measurement, optical and scanning electron microscopy, FTIR, XRD, and thermal analysis) evidenced the modification of the cotton fabric and the alteration of the film properties after zinc oxide inclusion. A comparison of the antimicrobial properties of the new CB with materials prepared with chitosan without benzaldehyde from our previous study verified the influence of the hydrophobicity and surface roughness of the fabric surface on the enhancement of antimicrobial activity. The microbial growth inhibition increased in the following order: fungal strain Candida lipolytica >Gram-positive bacteria Bacillus cereus >Gram-negative bacteria Pseudomonas aeruginosa. The samples containing zinc oxide particles completely inhibited the growth of all three model strains. The virucidal activity of the CB was higher against human adenovirus serotype 5 (HAdV-5) than against human respiratory syncytial virus (HRSV-S2) after 60 min of exposure. The CBZ displayed higher virucidal activity with a Δlog of 0.9 against both viruses.

2.
J Funct Biomater ; 14(2)2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36826905

RESUMO

A study of the formation of copper (II) complexes with hemorphin peptide motifs in alkalic water solutions is presented. The effect of the peptide ligand on the complexing properties of the Cu (II) ion was quantified by giving the stoichiometry and stability of the complex compounds in the medium in which they are formed using voltammetric (cyclic) and spectral (UV-Vis and fluorimetric) analytical techniques. The resulting complexes were examined via IR spectroscopy to detect M-N and M-O oscillations and using the EPR approach in solution and in the solid phase to view the coordination and ligand binding regime. The possibility of the synergistic action of copper ions in the antivirus protection processes of cotton fibers coated in the same solvent with the newly obtained complex compounds was also investigated. One of the advantages is the formation of the complexes in an environment where the immobilization takes place, which contributes to increasing the efficiency of the process. The obtained results may serve as an aid for future more detailed biological studies of structure-activity relationships (SARs).

3.
Am J Reprod Immunol ; 89(1): e13650, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36331422

RESUMO

PROBLEM: Long-lived mycobacterial L-forms (mL-forms) could be detected in the blood of BCG-vaccinated people. We have previously found mL-forms in term placentas and blood of neonates, delivered by healthy BCG-vaccinated mothers as first formal demonstration that BCG vaccination in the childhood of the woman could affect her placentobiome during pregnancy. Of note, the isolated mL-forms reverted to the cell-walled state of the parental BCG bacilli in vitro. METHOD OF STUDY: Here, we analyzed triple samples of blood, decidua and chorion taken from BCG-vaccinated pregnant women, directed to elective abortions (6-12 gestation weeks). The colonization of the primary samples with mycobacterial L-forms (mL-forms) was evaluated using microbiological isolation and subsequent identification by real time PCR and morphological characterization by light microscopy and SEM. The potential of early placenta-derived mL-forms to expand mycobacteria-reactive γδ T cells in vitro was assessed using FACS, whereas their immunogenicity in vivo was followed up after i.p. inoculation in rats. RESULTS: Our results showed two important findings: 1) viable filterable mL-forms varying in size, shape and proliferation modes are capable of colonizing the gestational tissues of BCG-vaccinated women early in pregnancy and 2) early placenta-derived mL-forms are not as immunogenic as walled M. bovis BCG bacilli, shown by lack of stimulation of mycobacteria-reactive γδ T cells co-cultured with early placenta-derived mL-forms and inefficient internalization of mL-forms by rat's peritoneal phagocytes in vivo. CONCLUSION: Although generally thought to be reduced in virulence, mL-forms could provide a reservoir, hidden from the immune system especially in an immune privileged niche like placenta.


Assuntos
Mães , Vacinação , Feminino , Humanos , Gravidez , Animais , Ratos , Reação em Cadeia da Polimerase em Tempo Real
4.
Molecules ; 27(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35897948

RESUMO

Some new N- and C-modified biomolecular peptide analogues of both VV-hemorphin-5 and VV-hemorphin-7 with varied amino acids (Cys, Glu, His), 1-adamantanecarboxylic acid, and niacin (nicotinic acid) were synthesized by solid-phase peptide synthesis-Fmoc (9-fluorenylmethoxy-carbonyl) chemistry and were characterized in water solutions with different pH using spectroscopic and electrochemical techniques. Basic physicochemical properties related to the elucidation of the peptide structure at physiological pH have been also studied. The results showed that the interaction of peptide compounds with light and electricity preserves the structural and conformational integrity of the compounds in the solutions. Moreover, textile cotton fibers were modified with the new compounds and the binding of the peptides to the surface of the material was proved by FTIR and SEM analysis. Washing the material with an alkaline soap solution did not show a violation of the modified structure of the cotton. Antiviral activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5), the antimicrobial activity against B. cereus and P. aeruginosa used as model bacterial strains and cytotoxic effect of the peptide derivatives and modified cotton textile material has been evaluated. Antimicrobial tests showed promising activity of the newly synthesized compounds against the used Gram-positive and Gram-negative bacteria. The compounds C-V, H-V, AC-V, and AH-V were found slightly more active than NH7C and NCH7. The activity has been retained after the deposition of the compounds on cotton fibers.


Assuntos
Anti-Infecciosos , Bactérias Gram-Negativas , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Fibra de Algodão , Bactérias Gram-Positivas , Humanos , Têxteis
5.
Plants (Basel) ; 11(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35807618

RESUMO

BACKGROUND: Bulgaria is a country with a wide range of medicinal plants, with uses in traditional medicine dating back for centuries. METHODS: Disc diffusion assay was used to evaluate the antimicrobial activity of the plant extracts. A cytopathic effect inhibition test was used for the assessment of the antiviral activity of the extracts. The virucidal activity of the extracts, their influence on the stage of viral adsorption, and their protective effect on uninfected cells were reported using the end-point dilution method, and Δlgs was determined as compared to the untreated controls. RESULTS: The results of the study reveal that the antibacterial potential of G. glabra and H. perforatum extracts in Gram-positive bacteria is more effective than in Gram-negative bacteria. When applied during the replication of HSV-1 and HCov-OC-43, only some of the extracts showed weak activity, with SI between 2 to 8.5. Almost all tested extracts inhibited the extracellular virions of the studied enveloped viruses (HSV-1 and HCov-OC-43) to a greater extent than of the non-enveloped viruses (PV-1 and HAdV-5). They inhibited the stage of viral adsorption (HSV-1) in the host cell (MDBK) to varying degrees and showed a protective effect on healthy cells (MDBK) before they were subjected to viral invasion (HSV-1). CONCLUSION: The antipathogenic potential of extracts of H. perforatum and G. glabra suggests their effectiveness as antimicrobial agents. All 13 extracts of the Bulgarian medicinal plants studied can be used to reduce viral yield in a wide range of viral infections.

6.
Biophys J ; 121(4): 607-619, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35090899

RESUMO

Nascent pre-mRNA 3'-end cleavage and polyadenylation (C/P) involves numerous proteins that recognize multiple RNA elements. Human CSTF2 binds to a downstream U- or G/U-rich sequence through its RNA recognition motif (RRM) regulating C/P. We previously reported the only known disease-related CSTF2 RRM mutant (CSTF2D50A) and showed that it changed the on-rate of RNA binding, leading to alternative polyadenylation in brains of mice carrying the same mutation. In this study, we further investigated the role of electrostatic interactions in the thermodynamics and kinetics of RNA binding for the CSTF2 RRM and the downstream consequences for regulation of C/P. By combining mutagenesis with NMR spectroscopy and biophysical assays, we confirmed that electrostatic attraction is the dominant factor in RRM binding to a naturally occurring U-rich RNA sequence. Moreover, we demonstrate that RNA binding is accompanied by an enthalpy-entropy compensation mechanism that is supported by changes in pico-to-nanosecond timescale RRM protein dynamics. We suggest that the dynamic binding of the RRM to U-rich RNA supports the diversity of sequences it encounters in the nucleus. Lastly, in vivo C/P assays demonstrate a competition between fast, high affinity RNA binding and efficient, correct C/P. These results highlight the importance of the surface charge of the RRM in RNA binding and the balance between nascent mRNA binding and C/P in vivo.


Assuntos
Poliadenilação , Precursores de RNA , Animais , Camundongos , Ligação Proteica , RNA/química , Precursores de RNA/genética , Precursores de RNA/metabolismo , Motivo de Reconhecimento de RNA , Eletricidade Estática
7.
Molecules ; 26(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34771015

RESUMO

Here we report on the synthesis and characterization of three new N-modified analogues of hemorphin-4 with rhodamine B. Modified with chloroacetyl, chloride cotton fabric has been dyed and color coordinates of the obtained textile materials were determined. Antiviral and virucidal activities of both the peptide-rhodamine B compounds and the dyed textile material were studied. Basic physicochemical properties (acid-base behavior, solvent influence, kinetics) related to the elucidation of structural activity of the new modified peptides based on their steric open/closed ring effect were studied. The obtained results lead to the conclusion that in protic solvent with change in pH of the environment, direct control over the dyeing of textiles can be achieved. Both the new hybrid peptide compounds and the modification of functionalized textile materials with these bioactive hemorphins showed virucidal activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5) for different time intervals (30 and 60 min) and the most active compound was Rh-3.


Assuntos
Adenoviridae/efeitos dos fármacos , Antivirais/farmacologia , Peptídeos/farmacologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Rodaminas/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Rodaminas/química , Rodaminas/isolamento & purificação , Fatores de Tempo
8.
Molecules ; 27(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35011479

RESUMO

This study evaluated the in vitro antineoplastic and antiviral potential and in vivo toxicity of twelve extracts with different polarity obtained from the herbaceous perennial plant Geum urbanum L. (Rosaceae). In vitro cytotoxicity was determined by ISO 10993-5/2009 on bladder cancer, (T-24 and BC-3C), liver carcinoma (HEP-G2) and normal embryonic kidney (HEK-293) cell lines. The antineoplastic activity was elucidated through assays of cell clonogenicity, apoptosis induction, nuclear factor kappa B p65 (NFκB p65) activation and total glutathione levels. Neutral red uptake study was applied for antiviral activity. The most promising G. urbanum extract was analyzed by UHPLC-HRMS. The acute in vivo toxicity analysis was carried out following OEDC 423. The ethyl acetate extract of aerial parts (EtOAc-AP) exhibited the strongest antineoplastic activity on bladder cancer cell lines (IC50 = 21.33-25.28 µg/mL) by inducing apoptosis and inhibiting NFκB p65 and cell clonogenicity. EtOAc and n-butanol extracts showed moderate antiviral activity against human adenovirus type 5 and human simplex virus type I. Seventy four secondary metabolites (gallic and ellagic acid derivatives, phenolic acids, flavonoids, etc.) were identified in EtOAc-AP by UHPLC-HRMS. This extract induced no signs of acute toxicity in liver and kidney specimens of H-albino mice in doses up to 210 mg/kg. In conclusion, our study contributes substantially to the detailed pharmacological characterization of G. urbanum, thus helping the development of health-promoting phytopreparations.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antivirais/farmacologia , Geum/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antivirais/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Especificidade de Órgãos/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Espectrometria de Massas em Tandem
9.
Anat Rec (Hoboken) ; 304(3): 631-646, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32537855

RESUMO

The peridural membrane (PDM) is a well-defined structure between dura mater and the wall of the spinal canal. The spine may be viewed as a multi-segmented joint, with the epidural cavity and neural foramina as joint spaces and PDM as synovial lining. The objective of this investigation was to determine if PDM has histological characteristics of synovium. Samples of the PDM of the thoraco-lumbar spine were taken from 23 human cadavers and analyzed with conventional light microscopy and confocal microscopy. Results were compared to reports on similar analyses of synovium in the literature. Histological distribution of areolar, fibrous, and adipose connective tissue in PDM was similar to synovium. The PDM has an intima and sub-intima. No basement membrane was identified. CD68, a marker for macrophage-like-synoviocytes, and CD55, a marker for fibroblast-like synoviocytes, were seen in the lining and sub-lining of the PDM. Multifunctional hyaluronan receptor CD44 and hyaluronic acid synthetase 2 marker HAS2 were abundantly present throughout the membrane. Marked presence of CD44, CD55, and HAS2 in the well-developed tunica muscularis of blood vessels and in the body of the PDM suggests a role in the maintenance and lubrication of the epidural cavity and neural foramina. Presence of CD68, CD55, and CD44 suggests a scavenging function and a role in the inflammatory response to noxious stimuli. Thus, the human PDM has histological and immunohistochemical characteristics of synovium. This suggests that the PDM may be important for the homeostasis of the flexible spine and the neural structures it contains.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígenos CD55/metabolismo , Receptores de Hialuronatos/metabolismo , Coluna Vertebral/metabolismo , Membrana Sinovial/metabolismo , Espaço Epidural/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Anat Rec (Hoboken) ; 304(4): 677-691, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32562360

RESUMO

A peridural membranous layer exists between the bony wall of the spinal canal and the dura mater, but reports on the anatomy of this structure have been inconsistent. The objective of this study is to give a precise description of the peridural membrane (PDM) and to define it unambiguously as a distinct and unique anatomical entity. Thirty-four cadaveric sections of human thoraco-lumbar spines were dissected. On gross examination, the PDM appears as a smooth hollow tube that covers the bony wall of the spinal canal. An evagination of this tube into the neural foramen contains the exiting spinal nerve. The entire epidural venous plexus, including its extension into the neural foramina, is contained in the body of the PDM. Histological examination of the PDM shows a variable distribution of veins arteries, lymphatics, and nerves embedded in a continuous sheath of fibrous, areolar, and adipose tissue. The posterior longitudinal ligament may be considered a dense condensation of fibrous tissue within the membrane. Thus, the PDM is a unique, continuous, and complete anatomical structure. In the spinal canal, the PDM is adjacent to the periosteum. In the neural foramen, suprapedicular PDM and pedicular periosteum separate anatomically to form a suprapedicular compartment, bounded anteriorly by the intervertebral disc and posteriorly by the facet joint. Trauma or degeneration of the disc or facet joint may lead to inflammation and pain sensitization of PDM. This protective mechanism may be of considerable importance for the functioning of the spine under conditions of strain.


Assuntos
Dura-Máter/anatomia & histologia , Espaço Epidural/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Cadáver , Humanos , Nervos Espinhais/anatomia & histologia
11.
PLoS One ; 15(12): e0240498, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33296397

RESUMO

The signal peptides, present at the N-terminus of many proteins, guide the proteins into cell membranes. In some proteins, the signal peptide is with an extended N-terminal region. Previously, it was demonstrated that the N-terminally extended signal peptide of the human PTPRJ contains a cluster of arginine residues, which attenuates translation. The analysis of the mammalian orthologous sequences revealed that this sequence is highly conserved. The PTPRJ transcripts in placentals, marsupials, and monotremes encode a stretch of 10-14 arginine residues, positioned 11-12 codons downstream of the initiating AUG. The remarkable conservation of the repeated arginine residues in the PTPRJ signal peptides points to their key role. Further, the presence of an arginine cluster in the extended signal peptides of other proteins (E3 ubiquitin-protein ligase, NOTCH3) is noted and indicates a more general importance of this cis-acting mechanism of translational suppression.


Assuntos
Sequência Conservada/genética , Biossíntese de Proteínas/genética , Sinais Direcionadores de Proteínas/genética , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/genética , Animais , Arginina/genética , Códon de Iniciação/genética , Humanos , RNA Mensageiro/genética , Receptor Notch3/genética , Sequências Repetitivas de Ácido Nucleico/genética , Alinhamento de Sequência
12.
Materials (Basel) ; 13(20)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066584

RESUMO

Two new copper complexes of hyperbranched polymers modified with dansyl units were synthesized and characterized by infrared spectroscopy (IR) and electron paramagnetic resonance (EPR) techniques. It was found that copper ions coordinate predominantly with nitrogen or oxygen atoms of the polymer molecule. The place of the formation of complexes and the number of copper ions involved depend on the chemical structure of the polymer. The antimicrobial activity of the new polymers and their Cu(II) complexes was tested against Gram-negative and Gram-positive bacterial and fungal strains. Copper complexes were found to have activity better than that of the corresponding ligands. The deposition of the modified branched polymers onto cotton fabrics prevents the formation of bacterial biofilms, which indicates that the studied polymers can find application in antibacterial textiles.

13.
Nucleic Acids Res ; 48(17): 9804-9821, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32816001

RESUMO

CSTF2 encodes an RNA-binding protein that is essential for mRNA cleavage and polyadenylation (C/P). No disease-associated mutations have been described for this gene. Here, we report a mutation in the RNA recognition motif (RRM) of CSTF2 that changes an aspartic acid at position 50 to alanine (p.D50A), resulting in intellectual disability in male patients. In mice, this mutation was sufficient to alter polyadenylation sites in over 1300 genes critical for brain development. Using a reporter gene assay, we demonstrated that C/P efficiency of CSTF2D50A was lower than wild type. To account for this, we determined that p.D50A changed locations of amino acid side chains altering RNA binding sites in the RRM. The changes modified the electrostatic potential of the RRM leading to a greater affinity for RNA. These results highlight the significance of 3' end mRNA processing in expression of genes important for brain plasticity and neuronal development.


Assuntos
Fator Estimulador de Clivagem/genética , Deficiência Intelectual/genética , Mutação de Sentido Incorreto , Poliadenilação , Motivo de Reconhecimento de RNA , Regiões 3' não Traduzidas , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Criança , Fator Estimulador de Clivagem/química , Fator Estimulador de Clivagem/metabolismo , Feminino , Células HeLa , Humanos , Deficiência Intelectual/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linhagem , Ligação Proteica
14.
15.
Sci Data ; 7(1): 178, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546682

RESUMO

A vast amount of public RNA-sequencing datasets have been generated and used widely to study transcriptome mechanisms. These data offer precious opportunity for advancing biological research in transcriptome studies such as alternative splicing. We report the first large-scale integrated analysis of RNA-Seq data of splicing factors for systematically identifying key factors in diseases and biological processes. We analyzed 1,321 RNA-Seq libraries of various mouse tissues and cell lines, comprising more than 6.6 TB sequences from 75 independent studies that experimentally manipulated 56 splicing factors. Using these data, RNA splicing signatures and gene expression signatures were computed, and signature comparison analysis identified a list of key splicing factors in Rett syndrome and cold-induced thermogenesis. We show that cold-induced RNA-binding proteins rescue the neurite outgrowth defects in Rett syndrome using neuronal morphology analysis, and we also reveal that SRSF1 and PTBP1 are required for energy expenditure in adipocytes using metabolic flux analysis. Our study provides an integrated analysis for identifying key factors in diseases and biological processes and highlights the importance of public data resources for identifying hypotheses for experimental testing.


Assuntos
Fatores de Processamento de RNA , RNA-Seq , Adipócitos/metabolismo , Processamento Alternativo , Animais , Linhagem Celular , Temperatura Baixa , Conjuntos de Dados como Assunto , Ribonucleoproteínas Nucleares Heterogêneas/genética , Camundongos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Síndrome de Rett/genética , Fatores de Processamento de Serina-Arginina/genética , Termogênese/genética , Transcriptoma
17.
Metab Brain Dis ; 35(3): 527-538, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31997264

RESUMO

Diabetes mellitus type 2 (T2DM) is characterized by resistance of insulin receptors and/or inadequate insulin secretion resulting in metabolic and structural complications including vascular diseases, arterial hypertension and different behavioral alterations. We aimed to study the effects of the antihypertensive angiotensin AT1 receptor antagonist losartan on the T2DM-induced changes of exploratory behavior, anxiety, nociception and short term memory in normotensive Wistar and spontaneously hypertensive rats (SHRs). The experimental model of T2DM induced by a combination of high fat diet and streptozotocin, decreased exploratory activity and increased the level of carbonylated proteins in selected brain structures in both strains; as well it increased corticosterone level, pain threshold, anxiety-like behavior, and decline short term memory only in SHRs. Losartan treatment alleviated some of the T2DM- induced metabolic complications, abolished the T2DM-induced hypo activity, and normalized the corticosterone level, carbonylated proteins in brain, nociception and memory. Losartan did not exert effect on the anxiety behavior in both strains. We showed that T2DM exerted more pronounced negative effects on the rats with comorbid hypertension as compared to normotensive rats. Overall effects on the studied behavioral parameters are related to decreased exploration of the new environment, increased anxiety-like behavior, and decline in short-term memory. The systemic sub-chronic treatment with an angiotensin AT1 receptor antagonist losartan ameliorated most of these complications.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Encéfalo/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Comportamento Exploratório/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Losartan/administração & dosagem , Animais , Encéfalo/metabolismo , Corticosterona/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Resistência à Insulina , Memória/efeitos dos fármacos , Nociceptividade/efeitos dos fármacos , Ratos , Ratos Endogâmicos SHR , Ratos Wistar
18.
Materials (Basel) ; 12(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540365

RESUMO

A second-generation poly(propylene imine) dendrimer modified with acridine and its Cu(II) complex have been synthesized for the first time. It has been found that two copper ions form complexes with the nitrogen atoms of the dendrimeric core by coordinate bonds. The new compounds have been characterized by nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), fourier-transform infrared spectroscopy (FTIR) and fluorescence spectroscopy. The spectral characteristics of the modified dendrimer have been measured in different organic solvents, and a negative fluorescence solvatochromism has been observed. The antimicrobial activity of the dendrimers has been tested against model pathogenic microorganisms in agar and by broth dilution method. The cotton fabric treated with both dendrimers has been evaluated towards pathogenic microorganisms. The obtained modified cotton fabrics have been shown to hamper bacterial growth and to prevent biofilm formation. Dendrimer cytotoxicity has been investigated in vitro in the model HEp-2 cell line.

19.
Bioorg Chem ; 85: 487-497, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30782563

RESUMO

A series of 60 nitrobenzonitrile analogues of the anti-viral agent MDL-860 were synthesized (50 of which are new) and evaluated for their activity against three types of enteroviruses (coxsackievirus B1, coxsackievirus B3 and poliovirus 1). Among them, six diaryl ethers (20e, 27e, 28e, 29e, 33e and 35e) demonstrated high in vitro activity (SI > 50) towards at least one of the tested viruses and very low cytotoxicity against human cells. Compound 27e possesses the broadest spectrum of activity towards all tested viruses in the same way as MDL-860 does. The most active derivatives (27e, 29e and 35e) against coxsackievirus B1 were tested in vivo in newborn mice experimentally infected with 20 MLD50 of coxsackievirus B1. Compound 29e showed promising in vivo activity (protection index 26% and 4 days lengthening of mean survival time). QSAR analysis of the substituent effects on the in vitro cytotoxicity (CC50) and anti-viral activity of the nitrobenzonitrile derivatives was carried out and adequate QSAR models for the anti-viral activity of the compounds against poliovirus 1 and coxsackievirus B1 were constructed.


Assuntos
Antivirais/farmacologia , Nitrilas/farmacologia , Poliovirus/efeitos dos fármacos , Antivirais/síntese química , Antivirais/química , Linhagem Celular , Cristalografia por Raios X , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nitrilas/síntese química , Nitrilas/química , Relação Quantitativa Estrutura-Atividade
20.
Nucleic Acids Res ; 46(22): 12022-12039, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30257008

RESUMO

Cleavage and polyadenylation (C/P) of mRNA is an important cellular process that promotes increased diversity of mRNA isoforms and could change their stability in different cell types. The cleavage stimulation factor (CstF) complex, part of the C/P machinery, binds to U- and GU-rich sequences located downstream from the cleavage site through its RNA-binding subunit, CstF-64. Less is known about the function of the other two subunits of CstF, CstF-77 and CstF-50. Here, we show that the carboxy-terminus of CstF-77 plays a previously unrecognized role in enhancing C/P by altering how the RNA recognition motif (RRM) of CstF-64 binds RNA. In support of this finding, we also show that CstF-64 relies on CstF-77 to be transported to the nucleus; excess CstF-64 localizes to the cytoplasm, possibly via interaction with cytoplasmic RNAs. Reverse genetics and nuclear magnetic resonance studies of recombinant CstF-64 (RRM-Hinge) and CstF-77 (monkeytail-carboxy-terminal domain) indicate that the last 30 amino acids of CstF-77 increases the stability of the RRM, thus altering the affinity of the complex for RNA. These results provide new insights into the mechanism by which CstF regulates the location of the RNA cleavage site during C/P.


Assuntos
Fator Estimulador de Clivagem/química , Fator Estimulador de Clivagem/fisiologia , Poliadenilação , Clivagem do RNA , Proteínas de Ligação a RNA/metabolismo , Células HeLa , Humanos , Conformação de Ácido Nucleico , Poliadenilação/genética , Domínios e Motivos de Interação entre Proteínas/genética , Clivagem do RNA/genética , Motivo de Reconhecimento de RNA/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Relação Estrutura-Atividade
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