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1.
SAR QSAR Environ Res ; 33(10): 779-792, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36330747

RESUMO

A novel decision-making procedure is proposed here for the first time to identify active/inactive and selective/non-selective dual inhibitors using consensus approaches and pools of k-nearest neighbours (kNN) classifications instead of individual models. Dual BRD4/PLK1 inhibition with adequate selectivity is a potential therapeutic strategy for targeting tumour cells in high-risk patients. We report the unique way to identify both active and selective dual BRD4/PLK1 inhibitors using consensus and kNN strategies together with two sources of receptor-based and ligand-based information which are the ranked binding energies of residues and important molecular features, respectively. The results of consensus approaches were compared with the results of individual kNN models. The chemical space similarity was measured using three different distance functions to increase the reliability. All activity and selectivity classification models were validated using cross-validation and y-randomization tests. The outcomes show that consensus approaches can increase the reliability and accuracy of active/inactive or selective/non-selective detections up to 90%. Consensus approaches also reached more balanced values of sensitivity and specificity compared to the individual kNN models because of the compensation in the integration of diverse sources of information.


Assuntos
Proteínas Nucleares , Relação Quantitativa Estrutura-Atividade , Humanos , Consenso , Reprodutibilidade dos Testes , Fatores de Transcrição , Proteínas de Ciclo Celular
2.
Cryo Letters ; 42(3): 146-153, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33970992

RESUMO

BACKGROUND: Antioxidants reduce oxidative stress and improve sperm quality during cryopreservation. OBJECTIVE: To investigate the effect of idebenone, resveratrol and taurine on the sperm quality and lipid peroxidation of cryopreserved crossbred ram semen. METHODS: In a split study, pooled ejaculates were divided into four aliquots cryopreserved in tris extender with no antioxidant (control), with idebenone (0.01 mM), resveratrol (0.1 mM), and taurine (40 mM). RESULT: Among all antioxidants, taurine treatment yielded significantly better sperm quality. Malondialdehyde (MDA) level in seminal plasma was significantly lower for taurine compared to the control, idebenone and resveratrol treatments. Moreover, sperm quality declined significantly in all the groups from pre-freeze to post-thaw. CONCLUSION: The findings indicate that taurine at 40 mM significantly improves sperm quality compared to 0.01 mM idebenone and 0.1 mM resveratrol, hence it can be considered as a potent and promising antioxidant supplement in tris extender for the cryopreservation of crossbred ram semen.


Assuntos
Criopreservação , Crioprotetores , Peroxidação de Lipídeos , Preservação do Sêmen , Carneiro Doméstico , Animais , Antioxidantes/farmacologia , Criopreservação/veterinária , Crioprotetores/farmacologia , Masculino , Resveratrol/farmacologia , Sêmen , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Taurina/farmacologia , Ubiquinona/análogos & derivados
3.
Mater Today Bio ; 8: 100081, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33210083

RESUMO

Pelvic organ prolapse is a common condition that affects 1 in 4 women across all age groups. It is mainly caused by vaginal birth injury and can be exacerbated by obesity and increased age. Until recently, treatment strategies often used non-degradable synthetic meshes for reconstructive surgery. However, owing to their frequent, unacceptable rate of adverse events such as mesh erosion, transvaginal meshes have been banned in many countries. Recent reports have highlighted the urgent need for biocompatible design of meshes for a safe and effective treatment in the long term. This study reports the design and evaluation of a novel, elastin based degradable mesh using an ovine model of POP as a potential surgical treatment. Elastin is a protein component of the ECM and provides elasticity to tissues throughout the body. Tropoelastin, the monomer subunit of elastin, has been used with success in electrospun constructs as it is a naturally cell interactive polymer. Biomaterials that incorporate tropoelastin support cell attachment and proliferation, and have been proven to encourage elastogenesis and angiogenesis in vitro and in vivo. The biological properties of tropoelastin were combined with the physical properties of PCL, a degradable synthetic polymer, with the aim of producing, characterizing and assessing the performance of continuous tropoelastin:PCL electrospun yarns. Using a modified spinneret electrospinning system and adjusting settings based on relative humidity, four blends of tropoelastin:PCL yarns were fabricated with concentration ratios of 75:25, 50:50, 25:75 and 0:100. Yarns were assessed for ease of manufacture, fibrous architecture, protein/polymer content, yarn stability - including initial tropoelastin release, mechanical strength, and ability to support cell growth. Based on overall favorable properties, a mesh woven from the 50:50 tropoelastin:PCL yarn was implanted into the vagina of a parous ewe with vaginal wall weakness as a model of pelvic organ prolapse. This mesh showed excellent integration with new collagen deposition by SEM and a predominant M2 macrophage response with few pro-inflammatory M1 macrophages after 30 days. The woven tropoelastin:PCL electrospun mesh shows potential as an alternative to non-degradable, synthetic pelvic organ prolapse mesh products.

4.
BMC Res Notes ; 13(1): 454, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32977859

RESUMO

OBJECTIVE: Endometriosis is a common and painful condition characterised by the formation of endometrial lesions within the peritoneal cavity. Previous studies have suggested a role for hedgehog signalling in the pathogenesis of endometriosis. We investigated the role of hedgehog signalling in the establishment of endometriosis lesions using 5E1, a hedgehog ligand neutralising antibody, and a mouse model of endometriosis. To mimic the initiation of endometriosis by retrograde menstruation, which is believed to occur in humans, donor mice underwent an artificial menstruation protocol. Fragments of menstrual endometrium were injected into the peritoneal cavity of estrogen primed recipients. Recipients received twice weekly injections of 5E1 or an isotype matched control antibody for three weeks. Lesions were collected and analysed for markers of epithelium, proliferation and apoptosis by immunofluorescence microscopy. RESULTS: Treatment with 5E1 reduced the number of lesions found on the mesentery. No significant changes were found in the size of lesions, abundance of endometrial epithelial cells, proliferation or apoptosis.


Assuntos
Endometriose , Proteínas Hedgehog , Animais , Anticorpos Neutralizantes , Endometriose/tratamento farmacológico , Endométrio , Feminino , Humanos , Ligantes , Camundongos , Transdução de Sinais
5.
Biomaterials ; 225: 119495, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606680

RESUMO

The widespread use of synthetic transvaginal polypropylene mesh for treating Pelvic Organ Prolapse (POP) has been curtailed due to serious adverse effects highlighted in 2008 and 2011 FDA warnings and subsequent legal action. We are developing new synthetic mesh to deliver endometrial mesenchymal stem cells (eMSC) to improve mesh biocompatibility and restore strength to prolapsed vaginal tissue. Here we evaluated knitted polyamide (PA) mesh in an ovine multiparous model using transvaginal implantation and matched for the degree of POP. Polyamide mesh dip-coated in gelatin and stabilised with 0.5% glutaraldehyde (PA/G) were used either alone or seeded with autologous ovine eMSC (eMSC/PA/G), which resulted in substantial mesh folding, poor tissue integration and 42% mesh exposure in the ovine model. In contrast, a two-step insertion protocol, whereby the uncoated PA mesh was inserted transvaginally followed by application of autologous eMSC in a gelatin hydrogel onto the mesh and crosslinked with blue light (PA + eMSC/G), integrated well with little folding and no mesh exposure. The autologous ovine eMSC survived 30 days in vivo but had no effect on mesh integration. The stiff PA/G constructs provoked greater myofibroblast and inflammatory responses in the vaginal wall, disrupted the muscularis layer and reduced elastin fibres compared to PA + eMSC/G constructs. This study identified the superiority of a two-step protocol for implanting synthetic mesh in cellular compatible composite constructs and simpler surgical application, providing additional translational value.


Assuntos
Teste de Materiais , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Prolapso de Órgão Pélvico/cirurgia , Telas Cirúrgicas , Actinas/metabolismo , Animais , Fenômenos Biomecânicos , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Glutaral/química , Leucócitos/metabolismo , Células-Tronco Mesenquimais/imunologia , Músculo Liso/patologia , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Nylons , Ovinos , Vagina/cirurgia
6.
Sci Rep ; 8(1): 6554, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29700360

RESUMO

The immunomodulatory properties of human endometrial mesenchymal stem cells (eMSC) have not been well characterised. Initial studies showed that eMSC modulated the chronic inflammatory response to a non-degradable polyamide/gelatin mesh in a xenogeneic rat skin wound repair model, but the mechanism remains unclear. In this study, we investigated the immunomodulatory effect of eMSC on the macrophage response to polyamide/gelatin composite mesh in an abdominal subcutaneous wound repair model in C57BL6 immunocompetent and NSG (NOD-Scid-IL2Rgamma null ) immunocompromised mice to determine whether responses differed in the absence of an adaptive immune system and NK cells. mCherry lentivirus-labelled eMSC persisted longer in NSG mice, inducing longer term paracrine effects. Inclusion of eMSC in the mesh reduced inflammatory cytokine (Il-1ß, Tnfα) secretion, and in C57BL6 mice reduced CCR7+ M1 macrophages surrounding the mesh on day 3 and increased M2 macrophage marker mRNA (Arg1, Mrc1, Il10) expression at days 3 and 7. In NSG mice, these effects were delayed and only observed at days 7 and 30 in comparison with controls implanted with mesh alone. These results show that the differences in the immune status in the two animals directly affect the survival of xenogeneic eMSC which leads to differences in the short-term and long-term macrophage responses to implanted meshes.


Assuntos
Comunicação Celular , Endométrio/citologia , Imunomodulação , Macrófagos/imunologia , Macrófagos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nylons , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Expressão Gênica , Genes Reporter , Hospedeiro Imunocomprometido , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos/imunologia , Células-Tronco Mesenquimais/citologia , Camundongos , Nylons/efeitos adversos , Próteses e Implantes/efeitos adversos , Transdução Genética
7.
Arch Pharm Res ; 36(8): 981-92, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23568383

RESUMO

The objective of this study was to develop and statistically optimize chitosan nanospheres. For this purpose chitosan powder was turned into nanospheres using tripolyphosphate as a crosslinker and through ionic gelation. D-optimal response surface design was applied to optimize the nanospheres. Their size and polydispersity index (PDI) were measured as the dependant variables. Then the inactivated influenza virus and/or CpG ODN or Quillaja saponin (QS) were incorporated into the chitosan nanospheres. The release profiles of the antigen and both adjuvants were obtained. The toxicity of the formulations was tested by XTT using Calu 6 cell lines. The size distribution and PDI of plain chitosan nanospheres was 581.1 ± 32.6 and 0.478 ± 0.04. After 4 h the release of antigen, QS and CpG from the chitosan matrix were 33, 36 and 62%, respectively. The inactivated virus remained intact during preparation, as revealed by the SDS-PAGE method. Differential scanning calorimetry and Fourier Transform Infrared Spectroscopy indicated no serious structural changes in the chitosan carrier in the presence of either the antigen or the immunoadjuvants. Although the antigen loaded into chitosan nanospheres showed slight cytotoxicity on lung-cancer cells, co-encapsulation of the adjuvant (especially CpG) lowered this effect. The results demonstrated that chitosan as a carrier and immunostimulator, along with CpG or QS adjuvants, creates a potential influenza vaccine delivery system which can be administered nasally.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Quitosana/administração & dosagem , Imunização/métodos , Vírus da Influenza A Subtipo H1N1 , Nanosferas/administração & dosagem , Adjuvantes Imunológicos/química , Administração Intranasal , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Quitosana/química , Humanos , Vírus da Influenza A Subtipo H1N1/química , Nanosferas/química , Pós
8.
Artigo em Inglês | MEDLINE | ID: mdl-19041278

RESUMO

Phosphorus-31 and aluminum-27 nuclear magnetic resonance techniques have been used to characterize the distribution of soluble aluminophosphate species in aqueous solutions of (2-hydroxyethyl) trimethylammonium chloride (2-HETMACl), phosphoric acid, and aluminum sulfate. Soluble aluminophosphate cations obtain from reactions of hexaaqua aluminum cations [A1(H(2)O)(6)](3+), with phosphate ligands (i.e., H(3)PO(4), H(2)PO(4)(-), and acid dimers H(6)P(2)O(8) and H(5)P(2)O(7)(-)). (31)P NMR and (27)Al NMR spectroscopies are very powerful techniques for characterization of the species present in the solution. A number of solutions containing different mole ratio of Al/P were prepared. The assignment of the peaks to aluminate connectivities is attempted, clarifying earlier works and producing information on the equilibrium between various aluminum-containing species (different aluminophosphate complexes). At least seven separated resonances were observed by (31)P NMR spectroscopy indicating presence of different complexes in aluminum phosphate solutions.


Assuntos
Alumínio/química , Fósforo/química , Radioisótopos/química , Compostos de Trimetil Amônio/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 70(5): 1167-72, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18083612

RESUMO

Resolution of binary mixtures of vitamin B12, methylcobalamin and B12 coenzyme with minimum sample pre-treatment and without analyte separation has been successfully achieved by methods of partial least squares algorithm with one dependent variable (PLS1), orthogonal signal correction/partial least squares (OSC/PLS), principal component regression (PCR) and hybrid linear analysis (HLA). Data of analysis were obtained from UV-vis spectra. The UV-vis spectra of the vitamin B12, methylcobalamin and B12 coenzyme were recorded in the same spectral conditions. The method of central composite design was used in the ranges of 10-80 mg L(-1) for vitamin B12 and methylcobalamin and 20-130 mg L(-1) for B12 coenzyme. The models refinement procedure and validation were performed by cross-validation. The minimum root mean square error of prediction (RMSEP) was 2.26 mg L(-1) for vitamin B12 with PLS1, 1.33 mg L(-1) for methylcobalamin with OSC/PLS and 3.24 mg L(-1) for B12 coenzyme with HLA techniques. Figures of merit such as selectivity, sensitivity, analytical sensitivity and LOD were determined for three compounds. The procedure was successfully applied to simultaneous determination of three compounds in synthetic mixtures and in a pharmaceutical formulation.


Assuntos
Análise Espectral/métodos , Vitamina B 12/análise , Vitamina B 12/química , Calibragem , Elétrons
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