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1.
Cell ; 150(5): 883-94, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22939618

RESUMO

The therapeutic utility of siRNAs is limited by the requirement for complex formulations to deliver them to tissues. If potent single-stranded RNAs could be identified, they would provide a simpler path to pharmacological agents. Here, we describe single-stranded siRNAs (ss-siRNAs) that silence gene expression in animals absent lipid formulation. Effective ss-siRNAs were identified by iterative design by determining structure-activity relationships correlating chemically modified single strands and Argonaute 2 (AGO2) activities, potency in cells, nuclease stability, and pharmacokinetics. We find that the passenger strand is not necessary for potent gene silencing. The guide-strand activity requires AGO2, demonstrating action through the RNAi pathway. ss-siRNA action requires a 5' phosphate to achieve activity in vivo, and we developed a metabolically stable 5'-(E)-vinylphosphonate (5'-VP) with conformation and sterioelectronic properties similar to the natural phosphate. Identification of potent ss-siRNAs offers an additional option for RNAi therapeutics and an alternate perspective on RNAi mechanism.


Assuntos
Proteínas Argonautas/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Células HeLa , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Organofosfonatos/metabolismo , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Complexo de Inativação Induzido por RNA/metabolismo , Compostos de Vinila/metabolismo
2.
PLoS Genet ; 18(9): e1010436, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36178986

RESUMO

Ferroptosis is an iron-dependent form of regulated cell death associated with uncontrolled membrane lipid peroxidation and destruction. Previously, we showed that dietary dihomo-gamma-linolenic acid (DGLA; 20: 3(n-6)) triggers ferroptosis in the germ cells of the model organism, Caenorhabditis elegans. We also demonstrated that ether lipid-deficient mutant strains are sensitive to DGLA-induced ferroptosis, suggesting a protective role for ether lipids. The vinyl ether bond unique to plasmalogen lipids has been hypothesized to function as an antioxidant, but this has not been tested in animal models. In this study, we used C. elegans mutants to test the hypothesis that the vinyl ether bond in plasmalogens acts as an antioxidant to protect against germ cell ferroptosis as well as to protect from whole-body tert-butyl hydroperoxide (TBHP)-induced oxidative stress. We found no role for plasmalogens in either process. Instead, we demonstrate that ether lipid-deficiency disrupts lipid homeostasis in C. elegans, leading to altered ratios of saturated and monounsaturated fatty acid (MUFA) content in cellular membranes. We demonstrate that ferroptosis sensitivity in both wild type and ether-lipid deficient mutants can be rescued in several ways that change the relative abundance of saturated fats, MUFAs and specific polyunsaturated fatty acids (PUFAs). Specifically, we reduced ferroptosis sensitivity by (1) using mutant strains unable to synthesize DGLA, (2) using a strain carrying a gain-of-function mutation in the transcriptional mediator MDT-15, or (3) by dietary supplementation of MUFAs. Furthermore, our studies reveal important differences in how dietary lipids influence germ cell ferroptosis versus whole-body peroxide-induced oxidative stress. These studies highlight a potentially beneficial role for endogenous and dietary MUFAs in the prevention of ferroptosis.


Assuntos
Ferroptose , Ácido 8,11,14-Eicosatrienoico/metabolismo , Animais , Antioxidantes/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Éter/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos Insaturados , Ferroptose/genética , Homeostase/genética , Ferro/metabolismo , Plasmalogênios/metabolismo , Compostos de Vinila , terc-Butil Hidroperóxido/metabolismo
3.
J Mammary Gland Biol Neoplasia ; 29(1): 15, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39017946

RESUMO

As both perimenopausal and menopausal periods are recognized critical windows of susceptibility for breast carcinogenesis, development of a physiologically relevant model has been warranted. The traditional ovariectomy model causes instant removal of the entire hormonal repertoire produced by the ovary, which does not accurately approximate human natural menopause with gradual transition. Here, we characterized the mammary glands of 4-vinylcyclohexene diepoxide (VCD)-treated animals at different time points, revealing that the model can provide the mammary glands with both perimenopausal and menopausal states. The perimenopausal gland showed moderate regression in ductal structure with no responsiveness to external hormones, while the menopausal gland showed severe regression with hypersensitivity to hormones. Leveraging the findings on the VCD model, effects of a major endocrine disruptor (polybrominated diphenyl ethers, PBDEs) on the mammary gland were examined during and after menopausal transition, with the two exposure modes; low-dose, chronic (environmental) and high-dose, subacute (experimental). All conditions of PBDE exposure did not augment or compromise the macroscopic ductal reorganization resulting from menopausal transition and/or hormonal treatments. Single-cell RNA sequencing revealed that the experimental PBDE exposure during the post-menopausal period caused specific transcriptomic changes in the non-epithelial compartment such as Errfi1 upregulation in fibroblasts. The environmental PBDE exposure resulted in similar transcriptomic changes to a lesser extent. In summary, the VCD mouse model provides both perimenopausal and menopausal windows of susceptibility for the breast cancer research community. PBDEs, including all tested models, may affect the post-menopausal gland including impacts on the non-epithelial compartments.


Assuntos
Cicloexenos , Glândulas Mamárias Animais , Perimenopausa , Compostos de Vinila , Animais , Feminino , Camundongos , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Animais/metabolismo , Perimenopausa/efeitos dos fármacos , Perimenopausa/metabolismo , Menopausa/metabolismo , Menopausa/efeitos dos fármacos , Disruptores Endócrinos/efeitos adversos , Modelos Animais de Doenças , Humanos , Éteres Difenil Halogenados/toxicidade
4.
Exp Physiol ; 109(5): 711-728, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38500268

RESUMO

The abrupt cessation of ovarian hormone release is associated with declines in muscle contractile function, yet the impact of gradual ovarian failure on muscle contractility across peri-, early- and late-stage menopause remains unclear. In this study, a 4-vinylcyclohexene diepoxide (VCD)-induced ovarian failure mouse model was used to examine time course changes in muscle mechanical function. Plantar flexors of female mice (VCD: n = 10; CON: n = 8) were assessed at 40 (early perimenopause), 80 (late perimenopause), 120 (menopause onset) and 176 (late menopause) days post-initial VCD injection. A torque-frequency relationship was established across a range of frequencies (10-200 Hz). Isotonic dynamic contractions were elicited against relative loads (10-80% maximal isometric torque) to determine the torque-velocity-power relationship. Mice then performed a fatigue task using intermittent 100 Hz isometric contractions until torque dropped by 60%. Recovery of twitch, 10 Hz and 100 Hz torque were tracked for 10 min post-task failure. Additionally, intact muscle fibres from the flexor digitorum brevis underwent a fatigue task (50 repetitions at 70 Hz), and 10 and 100 Hz tetanic [Ca2+] were monitored for 10 min afterward. VCD mice exhibited 16% lower twitch torque than controls across all time points. Apart from twitch torque, 10 Hz torque and 10 Hz tetanic [Ca2+], where VCD showed greater values relative to pre-fatigue during recovery, no significant differences were observed between control and VCD mice during recovery. These results indicate that gradual ovarian failure has minimal detriments to in vivo muscle mechanical function, with minor alterations observed primarily for low-frequency stimulation during recovery from fatigue.


Assuntos
Cálcio , Contração Muscular , Fadiga Muscular , Músculo Esquelético , Compostos de Vinila , Animais , Feminino , Camundongos , Compostos de Vinila/farmacologia , Músculo Esquelético/fisiopatologia , Músculo Esquelético/metabolismo , Fadiga Muscular/fisiologia , Contração Muscular/fisiologia , Cálcio/metabolismo , Torque , Camundongos Endogâmicos C57BL , Cicloexenos/farmacologia , Contração Isométrica/fisiologia , Insuficiência Ovariana Primária/fisiopatologia , Insuficiência Ovariana Primária/metabolismo
5.
Mol Pharm ; 21(4): 1933-1941, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502549

RESUMO

Islatravir, a highly potent nucleoside reverse transcriptase translocation inhibitor (NRTTI) for the treatment of HIV, has great potential to be formulated as ethylene-vinyl acetate (EVA) copolymer-based implants via hot melt extrusion. The crystallinity of EVA determines its physical and rheological properties and may impact the drug-eluting implant performance. Herein, we describe the systematic analysis of factors affecting the EVA crystallinity in islatravir implants. Differential scanning calorimetry (DSC) on EVA and solid-state NMR revealed drug loading promoted EVA crystallization, whereas BaSO4 loading had negligible impact on EVA crystallinity. The sterilization through γ-irradiation appeared to significantly impact the EVA crystallinity and surface characteristics of the implants. Furthermore, DSC analysis of thin implant slices prepared with an ultramicrotome indicated that the surface layer of the implant was more crystalline than the core. These findings provide critical insights into factors affecting the crystallinity, mechanical properties, and physicochemical properties of the EVA polymer matrix of extruded islatravir implants.


Assuntos
Desoxiadenosinas , Etilenos , Polivinil , Compostos de Vinila , Polivinil/química
6.
Mol Pharm ; 21(2): 770-780, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38181202

RESUMO

The R3m molecular descriptor (R-GETAWAY third-order autocorrelation index weighted by the atomic mass) has previously been shown to encode molecular attributes that appear to be physically and chemically relevant to grouping diverse active pharmaceutical ingredients (API) according to their potential to form persistent amorphous solid dispersions (ASDs) with polyvinylpyrrolidone-vinyl acetate copolymer (PVPVA). The initial R3m dispersibility model was built by using a single three-dimensional (3D) conformation for each drug molecule. Since molecules in the amorphous state will adopt a distribution of conformations, molecular dynamics simulations were performed to sample conformations that are probable in the amorphous form, which resulted in a distribution of R3m values for each API. Although different conformations displayed R3m values that differed by as much as 0.4, the median of each R3m distribution and the value predicted from the single 3D conformation were very similar for most structures studied. The variability in R3m resulting from the distribution of conformations was incorporated into a logistic regression model for the prediction of ASD formation in PVPVA, which resulted in a refinement of the classification boundary relative to the model that only incorporated a single conformation of each API.


Assuntos
Polímeros , Povidona , Polímeros/química , Povidona/química , Compostos de Vinila/química , Liberação Controlada de Fármacos , Solubilidade , Composição de Medicamentos/métodos
7.
Mol Pharm ; 21(6): 2908-2921, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38743928

RESUMO

The physical stability of amorphous solid dispersions (ASDs) is a major topic in the formulation research of oral dosage forms. To minimize the effort of investigating the long-term stability using cost- and time-consuming experiments, we developed a thermodynamic and kinetic modeling framework to predict and understand the crystallization kinetics of ASDs during long-term storage below the glass transition. Since crystallization of the active phrarmaceutical ingredients (APIs) in ASDs largely depends on the amount of water absorbed by the ASDs, water-sorption kinetics and API-crystallization kinetics were considered simultaneously. The developed modeling approach allows prediction of the time evolution of viscosity, supersaturation, and crystallinity as a function of drug load, relative humidity, and temperature. It was applied and evaluated against two-year-lasting crystallization experiments of ASDs containing nifedipine and copovidone or HPMCAS measured in part I of this work. We could show that the proposed modeling approach is able to describe the interplay between water sorption and API crystallization and to predict long-term stabilities of ASDs just based on short-term measurements. Most importantly, it enables explaining and understanding the reasons for different and sometimes even unexpected crystallization behaviors of ASDs.


Assuntos
Cristalização , Água , Cristalização/métodos , Água/química , Cinética , Estabilidade de Medicamentos , Nifedipino/química , Compostos de Vinila/química , Termodinâmica , Pirrolidinas/química , Viscosidade , Química Farmacêutica/métodos , Umidade , Temperatura , Solubilidade , Metilcelulose/química , Metilcelulose/análogos & derivados
8.
Mol Pharm ; 21(6): 3017-3026, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38758116

RESUMO

Sucrose and trehalose pharmaceutical excipients are employed to stabilize protein therapeutics in a dried state. The mechanism of therapeutic protein stabilization is dependent on the sugars being present in an amorphous solid-state. Colyophilization of sugars with high glass transition polymers, polyvinylpyrrolidone (PVP), and poly(vinylpyrrolidone vinyl acetate) (PVPVA), enhances amorphous sugar stability. This study investigates the stability of colyophilized sugar-polymer systems in the frozen solution state, dried state postlyophilization, and upon exposure to elevated humidity. Binary systems of sucrose or trehalose with PVP or PVPVA were lyophilized with sugar/polymer ratios ranging from 2:8 to 8:2. Frozen sugar-PVPVA solutions exhibited a higher glass transition temperature of the maximally freeze-concentrated amorphous phase (Tg') compared to sugar-PVP solutions, despite the glass transition temperature (Tg) of PVPVA being lower than PVP. Tg values of all colyophilized systems were in a similar temperature range irrespective of polymer type. Greater hydrogen bonding between sugars and PVP and the lower hygroscopicity of PVPVA influenced polymer antiplasticization effects and the plasticization effects of residual water. Plasticization due to water sorption was investigated in a dynamic vapor sorption humidity ramping experiment. Lyophilized sucrose systems exhibited increased amorphous stability compared to trehalose upon exposure to the humidity. Recrystallization of trehalose was observed and stabilized by polymer addition. Lower concentrations of PVP inhibited trehalose recrystallization compared to PVPVA. These stabilizing effects were attributed to the increased hydrogen bonding between trehalose and PVP compared to trehalose and PVPVA. Overall, the study demonstrated how differences in polymer hygroscopicity and hydrogen bonding with sugars influence the stability of colyophilized amorphous dispersions. These insights into excipient solid-state stability are relevant to the development of stabilized biopharmaceutical solid-state formulations.


Assuntos
Estabilidade de Medicamentos , Excipientes , Liofilização , Polímeros , Povidona , Temperatura de Transição , Trealose , Liofilização/métodos , Povidona/química , Trealose/química , Excipientes/química , Polímeros/química , Sacarose/química , Açúcares/química , Ligação de Hidrogênio , Armazenamento de Medicamentos , Química Farmacêutica/métodos , Varredura Diferencial de Calorimetria , Umidade , Pirrolidinas/química , Compostos de Vinila/química
9.
Biomacromolecules ; 25(6): 3823-3830, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38773865

RESUMO

Sustainability and circularity are key issues facing the global polymer industry. The search for biodegradable and environmentally-friendly polymers that can replace conventional materials is a difficult challenge that has been met with limited success. Alternatives must be cost-effective, scalable, and provide equivalent performance. We report that latexes made by the conventional emulsion polymerization of vinyl acetate and functional vinyl ester monomers are efficient thickeners for consumer products and biodegrade in wastewater. This approach uses readily-available starting materials and polymerization is carried out in water at room temperature, in one pot, and generates negligible waste. Moreover, the knowledge that poly(vinyl ester)s are biodegradable will lead to the design of new green polymer materials.


Assuntos
Emulsões , Emulsões/química , Polimerização , Polímeros/química , Álcalis/química , Biodegradação Ambiental , Látex/química , Compostos de Vinila/química , Águas Residuárias/química
10.
Pharm Res ; 41(6): 1233-1245, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744732

RESUMO

PURPOSE: This study was designed to develop ibuprofen (IBU) sustained-release amorphous solid dispersion (ASD) using polymer composites matrix with drug release plateaus for stable release and to further reveal intrinsic links between polymer' matrix ratios and drug release behaviors. METHODS: Hydrophilic polymers and hydrophobic polymers were combined to form different composite matrices in developing IBU ASD formulations by hot melt extrusion technique. The intrinsic links between the mixed polymer matrix ratio and drug dissolution behaviors was deeply clarified from the dissolution curves of hydrophilic polymers and swelling curves of composite matrices, and intermolecular forces among the components in ASDs. RESULTS: IBU + ammonio methacrylate copolymer type B (RSPO) + poly(1-vinylpyrrolidone-co-vinyl acetate) (PVP VA64) physical mixtures presented unstable release behaviors with large error bars due to inhomogeneities at the micrometer level. However, IBU-RSPO-PVP VA64 ASDs showed a "dissolution plateau phenomenon", i.e., release behaviors of IBU in ASDs were unaffected by polymer ratios when PVP VA64 content was 35% ~ 50%, which could reduce risks of variations in release behaviors due to fluctuations in prescriptions/processes. The release of IBU in ASDs was simultaneously regulated by the PVP VA64-mediated "dissolution" and RSPO-PVP VA64 assembly-mediated "swelling". Radial distribution function suggested that similar intermolecular forces between RSPO and PVP VA64 were key mechanisms for the "dissolution plateau phenomenon" in ASDs at 35% ~ 50% of PVP VA64. CONCLUSIONS: This study provided ideas for developing ASD sustained-release formulations with stable release plateau modulated by polymer combinations, taking full advantages of simple process/prescription, ease of scale-up and favorable release behavior of ASD formulations.


Assuntos
Preparações de Ação Retardada , Composição de Medicamentos , Liberação Controlada de Fármacos , Ibuprofeno , Polímeros , Preparações de Ação Retardada/química , Ibuprofeno/química , Ibuprofeno/administração & dosagem , Polímeros/química , Composição de Medicamentos/métodos , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Tecnologia de Extrusão por Fusão a Quente/métodos , Compostos de Vinila/química , Pirrolidinas/química , Química Farmacêutica/métodos , Povidona/química
11.
Bioorg Med Chem Lett ; 109: 129855, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38908766

RESUMO

The role of G-quadruplex (G4) in cellular processes can be investigated by the covalent modification of G4-DNA using alkylating reagents. Controllable alkylating reagents activated by external stimuli can react elegantly and selectively. Herein, we report a chemical activation system that can significantly boost the reaction rate of methylamine-protected vinyl-quinazolinone (VQ) derivative for the alkylation of G4-DNA. The two screened activators can transform low-reactive VQ-NHR' to highly reactive intermediates following the Michael addition mechanism. This approach expands the toolbox of activable G4 alkylating reagents.


Assuntos
Quadruplex G , Metilaminas , Quinazolinonas , Alquilação , Quadruplex G/efeitos dos fármacos , Metilaminas/química , Metilaminas/farmacologia , Metilaminas/síntese química , Quinazolinonas/química , Quinazolinonas/farmacologia , Quinazolinonas/síntese química , Humanos , Estrutura Molecular , DNA/química , Compostos de Vinila/química , Compostos de Vinila/farmacologia
12.
Org Biomol Chem ; 22(16): 3273-3278, 2024 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-38572769

RESUMO

Arylsulfonyl group-bearing α,ß-unsaturated enol esters were readily assembled via the Cs2CO3-mediated union of 2-bromoallyl sulfones and cinnamic acids. The overall transformation is equivalent to an sp2 carbon-oxygen coupling reaction, and therefore constitutes a formal vinylic substitution. Several of the products display promising levels of antiproliferative activities higher than that of the anticancer drug carboplatin. Thiophenol reacted with 2-bromoallyl sulfones under identical conditions to afford α-thiophenyl-α'-tosyl acetone via an apparent aerial oxidation.


Assuntos
Antineoplásicos , Proliferação de Células , Ésteres , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Ésteres/química , Ésteres/farmacologia , Ésteres/síntese química , Humanos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Sulfonas/química , Sulfonas/farmacologia , Sulfonas/síntese química , Relação Estrutura-Atividade , Compostos de Vinila/química , Compostos de Vinila/farmacologia , Compostos de Vinila/síntese química
13.
Macromol Rapid Commun ; 45(15): e2400147, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38875713

RESUMO

Hydrophilicity is one important drawback of bio-based aerogels. To overcome this issue, a novel approach for the preparation of mesoporous, water repellent aerogels is introduced, which combines synthesis of cross-linked bio-based copolymers from methacrylate copolymerizations, followed by solvent exchange and supercritical drying steps. The influence of monomers with different nonpolar ester groups (methyl, vanillin, tetrahydrofurfuryl) on textural properties and water contact angles of the dry products is assessed. Final aerogels show generally high overall porosities (≈96%), low densities (0.07-0.11 g cm-3) as well as fine, mainly mesoporous networks, and specific surface areas in the range of 120-240 m2 g-1. Hereby, choice of the methacrylate ester groups results in differences of the resulting pore-size distributions. Water repellency tests show stable static water contact angles in the hydrophobic range (≈100°) achieved for the substrate containing the vanillin ester group. On the contrary the other substrates absorb water quickly, which indicates a decisive role of the ester group. The presented approach opens up a new pathway to bio-based aerogels with intrinsic hydrophobicity. It is suggested that the properties are tailored by the choice of the monomer structure, hence enabling further adaption and optimization of the products.


Assuntos
Géis , Interações Hidrofóbicas e Hidrofílicas , Polimerização , Polímeros , Géis/química , Géis/síntese química , Polímeros/química , Polímeros/síntese química , Porosidade , Água/química , Compostos de Vinila/química , Estrutura Molecular , Benzaldeídos/química
14.
Chirality ; 36(2): e23645, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38384154

RESUMO

We are looking into how well a copolymeric material made of poly (maleic acid-co-4-vinylpyridine) cross-linked with divinylbenzene can separate L-norepinephrine (L-NEP) from (±)-NEP. The initial step in this direction was the synthesis and subsequent analysis of L-NEP-maleimide chiral derivative. A 4-vinylpyridine/divinylbenzene combination was copolymerized with the resultant chiral maleimide. After heating the polymer materials in a high-alkaline environment to breakdown the connecting imide bonds, they were acidified in an HCl solution to eliminate the incorporated L-NEP species. Fourier transform infrared spectroscopy (FTIR) and a scanning electron microscope were used to examine the imprinted L-NEP-imprinted materials. The manufactured L-NEP-imprinted materials exhibited selectivity characteristics that were over 11 times greater for L-NEP than D-norepinephrine. The highest capacity observed in Langmuir adsorption studies was 170 mg/g at a pH of 7. After optical separation using a column technique, it was determined that the enantiomeric excess levels of D-norepinephrine and L-NEP in the first feeding and subsequent recovery solutions were 95% and 81%, respectively.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Compostos de Vinila , Norepinefrina , Impressão Molecular/métodos , Estereoisomerismo , Polímeros/química , Adsorção , Maleimidas
15.
J Sep Sci ; 47(5): e2300746, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471966

RESUMO

In this work, monodisperse and nano-porous poly(bismaleimide-co-divinylbenzene) microspheres with large specific surface area (427.6 m2 /g) and rich pore structure were prepared by one-pot self-stable precipitation polymerization of 2,2'-bis[4-(4-maleimidophenoxy) phenyl] propane and divinylbenzene. The prepared poly(bismaleimide-co-divinylbenzene) microspheres were employed as dispersive solid-phase extraction (DSPE) adsorbent for the extraction of triazine herbicides. Under optimized conditions, good linearities were obtained between the peak area and the concentration of triazine herbicides in the range of 1-400 µg/L (R2 ≥ 0.9987) with the limits of detection of 0.12-0.31 µg/L. Triazine herbicides were detected using the described approach in vegetable samples (i.e., cucumber, tomato, and maize) with recoveries of 93.6%-117.3% and relative standard deviations of 0.4%-3.5%. In addition, the recoveries of triazine herbicides remained above 80.7% after being used for nine DSPE cycles, showing excellent reusability of poly(bismaleimide-co-divinylbenzene) microspheres. The adsorption of poly(bismaleimide-co-divinylbenzene) microspheres toward triazine herbicides was a monolayer and chemical adsorption. The adsorption mechanism between triazine herbicides and adsorbents might be a combination of hydrogen bonding, electrostatic interaction, and π-π conjugation. The results confirmed the potential use of the poly(bismaleimide-co-divinylbenzene) microspheres-based DSPE coupled to the high-performance liquid chromatography method for the detection of triazine herbicide residues in vegetable samples.


Assuntos
Herbicidas , Verduras , Compostos de Vinila , Verduras/química , Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Porosidade , Triazinas/análise , Extração em Fase Sólida/métodos , Herbicidas/análise , Limite de Detecção
16.
Ecotoxicol Environ Saf ; 269: 115811, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086265

RESUMO

Our previous study reveals that maternal exposure to 4-vinylcyclohexene diepoxide (VCD) during pregnancy causes insufficient ovarian follicle reserve and decreased fertility in offspring. The present study aims to further explore the reasons for the significant decline of fecundity in mice caused by VCD, and to clarify the changes of gut microbiota and microbial metabolites in F1 mice. The ovarian metabolomics, gut microbiota and microbial metabolites were analyzed. The results of ovarian metabolomics analysis showed that maternal VCD exposure during pregnancy significantly reduced the concentration of carnitine in the ovaries of F1 mice, while supplementation with carnitine (isovalerylcarnitine and valerylcarnitine) significantly increased the number of ovulation. The results of 16 S rDNA-seq and microbial metabolites analysis showed that maternal VCD exposure during pregnancy caused disordered gut microbiota, increased abundance of Parabacteroides and Flexispira bacteria that are involved in secondary bile acid synthesis. The concentrations of NorDCA, LCA-3S, DCA and other secondary bile acids increased significantly. Our results indicate that maternal exposure to VCD during pregnancy leads to disorder in gut microbiota and bile acid metabolism in F1 mice, accompanying with decreased ovarian function, providing further evidence that maternal exposure to VCD during pregnancy has intergenerational deleterious effects on offspring.


Assuntos
Microbioma Gastrointestinal , Compostos de Vinila , Gravidez , Feminino , Humanos , Camundongos , Animais , Exposição Materna/efeitos adversos , Cicloexenos/toxicidade , Ácidos e Sais Biliares , Carnitina
17.
Arch Pharm (Weinheim) ; 357(7): e2300651, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38570819

RESUMO

A series of D-ring modified steroids bearing a vinyl ketone pendant were synthesized and evaluated for antiproliferative activity against breast cancer cell line and cytochromes P450. The lead compound, 21-vinyl 20-keto-pregnene (2f) (IC50 = 2.4 µM), was shown to be a promising candidate for future anticancer drug design, particularly against estrogen receptor α (ERα)-positive breast cancer. The lead compound was found to have a significant effect on the signaling pathways in parental and 4-hydroxytamoxifen-resistant cells. Compound 2f modulated the ERK, cyclin D1, and CDK4 pathways and blocked the expression of ERα, the main driver of breast cancer growth. Compound 2f significantly reduced 17ß-estradiol-induced progesterone receptor expression. Accumulation of cleaved poly(ADP-ribose) polymerase in cells treated with compound 2f indicated induction of apoptosis. The selectivity analysis showed that lead compound 2f produces no significant effects on cytochromes P450, CYP19A1, CYP21A2, and CYP7B1.


Assuntos
Antineoplásicos , Neoplasias da Mama , Proliferação de Células , Receptor alfa de Estrogênio , Transdução de Sinais , Humanos , Receptor alfa de Estrogênio/metabolismo , Receptor alfa de Estrogênio/antagonistas & inibidores , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Pregnenos/farmacologia , Pregnenos/síntese química , Pregnenos/química , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Estrutura Molecular , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Compostos de Vinila/farmacologia , Compostos de Vinila/síntese química , Compostos de Vinila/química
18.
Drug Dev Ind Pharm ; 50(4): 285-296, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38486377

RESUMO

The overactive bladder is a condition characterized by a sudden urge to urinate, even with small volumes of urine present in the bladder. The current treatments available for this pathology consist on conservative approaches and the continuous administration of drugs, which when made by conventional methods has limitations related to the first pass metabolism, bioavailability, severe side effects, and low patient adherence to treatments, ultimately leading to low effectiveness. Within this context, the present work proposes the design, manufacture, and characterization of an intravesical implant for the treatment of overactive bladder pathology, using EVA copolymer as a matrix and oxybutynin as a drug. The fabrication of devices through two manufacturing techniques (extrusion and additive manufacturing by fused filament fabrication, FFF) and the evaluation of the implants through characterization tests was proposed. The usability and functionality were evaluated through simulated insertion of the device/prototype in a bladder model through catheter insertion tests. The safety and effectiveness of the devices was investigated from mechanical testing as well as drug release assays. Drug release assays presented a burst release in the first 24 h, followed by a release of 1.8 and 2.8 mg/d, totalizing 32 d. Mechanical tests demonstrated an increase in the stiffness of the specimens due to the addition of the drug, showing a change in maximum stress and strain at break. The released dose was higher than that usually presented when considering the oral administration route, showing the optimization of the development of this implant has the potential to improve the quality of life of patients with overactive bladder.


Assuntos
Bexiga Urinária Hiperativa , Compostos de Vinila , Humanos , Bexiga Urinária Hiperativa/tratamento farmacológico , Preparações Farmacêuticas , Qualidade de Vida , Etilenos/uso terapêutico , Impressão Tridimensional
19.
Int J Mol Sci ; 25(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38396972

RESUMO

Due to growing concerns about environmental pollution from plastic waste, plastic recycling research is gaining momentum. Traditional methods, such as incorporating inorganic particles, increasing cross-linking density with peroxides, and blending with silicone monomers, often improve mechanical properties but reduce flexibility for specific performance requirements. This study focuses on synthesizing silica nanoparticles with vinyl functional groups and evaluating their mechanical performance when used in recycled plastics. Silica precursors, namely sodium silicate and vinyltrimethoxysilane (VTMS), combined with a surfactant, were employed to create pores, increasing silica's surface area. The early-stage introduction of vinyl functional groups prevented the typical post-synthesis reduction in surface area. Porous silica was produced in varying quantities of VTMS, and the synthesized porous silica nanomaterials were incorporated into recycled polyethylene to induce cross-linking. Despite a decrease in surface area with increasing VTMS content, a significant surface area of 883 m2/g was achieved. In conclusion, porous silica with the right amount of vinyl content exhibited improved mechanical performance, including increased tensile strength, compared to conventional porous silica. This study shows that synthesized porous silica with integrated vinyl functional groups effectively enhances the performance of recycled plastics.


Assuntos
Nanopartículas , Nanoestruturas , Silanos , Compostos de Vinila , Dióxido de Silício , Reciclagem , Poluição Ambiental
20.
Int J Mol Sci ; 25(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928161

RESUMO

Magnoliae Flos (MF) is a medicinal herb widely employed in traditional medicine for relieving sinusitis, allergic rhinitis, headaches, and toothaches. Here, we investigated the potential preventive effects of MF extract (MFE) against 4-vinylcyclohexene diepoxide (VCD)-induced ovotoxicity in ovarian cells and a mouse model of premature ovarian insufficiency (POI). The cytoprotective effects of MFE were assessed using CHO-K1 or COV434 cells. In vivo, B6C3F1 female mice were intraperitoneally injected with VCD for two weeks to induce POI, while MFE was orally administered for four weeks, beginning one week before VCD administration. VCD led to a significant decline in the viabilities of CHO-K1 and COV434 cells and triggered excessive reactive oxygen species (ROS) production and apoptosis specifically in CHO-K1 cells. However, pretreatment with MFE effectively prevented VCD-induced cell death and ROS generation, while also activating the Akt signaling pathway. In vivo, MFE increased relative ovary weights, follicle numbers, and serum estradiol and anti-Müllerian hormone levels versus controls under conditions of ovary failure. Collectively, our results demonstrate that MFE has a preventive effect on VCD-induced ovotoxicity through Akt activation. These results suggest that MFE may have the potential to prevent and manage conditions such as POI and diminished ovarian reserve.


Assuntos
Cricetulus , Ovário , Extratos Vegetais , Insuficiência Ovariana Primária , Espécies Reativas de Oxigênio , Animais , Feminino , Camundongos , Células CHO , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/prevenção & controle , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Compostos de Vinila/farmacologia , Cicloexenos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Modelos Animais de Doenças , Transdução de Sinais/efeitos dos fármacos
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