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1.
Artigo em Inglês | MEDLINE | ID: mdl-38987421

RESUMO

PURPOSE: To evaluate the predictive value of serum AMH for clinical pregnancy in non-infertile population undergoing intrauterine insemination with donor sperm (ds-IUI). METHODS: This multicenter prospective study (ClinicalTrials.gov ID: NCT06263192) recruited all non-infertile women undergoing ds-IUI from June 2020 to December 2022 in three different fertility clinics in Spain and Chile. Indications for ds-IUI included severe oligoasthenoteratozoospermia, female partner, or single status. Clinical pregnancy rates were compared between women with AMH ≥ 1.1 and < 1.1 ng/mL. The main outcome measure was the cumulative clinical pregnancy rate after up to 4 ds-IUI cycles. RESULTS: A total of 458 ds-IUI cycles were performed among 245 patients, of whom 108 (44.08%) achieved clinical pregnancy within 4 cycles, 60.2% of these occurring in the first attempt and 84.2% after two attempts. We found no significant differences in AMH levels or other parameters (such as age, BMI, FSH, AFC) between women who became pregnant and those who did not. Cumulative pregnancy rates and logistic regression analysis revealed that AMH ≥ 1.1 ng/mL was not predictive of ds-IUI success. While a high positive correlation was observed between AFC and AMH (r = 0.67, p < 0.001), ROC curve analyses indicated that neither of these ovarian reserve markers accurately forecasts cumulative ds-IUI outcomes in non-infertile women. CONCLUSIONS: The findings of this multicenter study suggest that AMH is not a reliable predictor of pregnancy in non-infertile women undergoing ds-IUI. Even women with low AMH levels can achieve successful pregnancy outcomes, supporting the notion that diminished ovarian reserve should not restrict access to ds-IUI treatments in eligible non-infertile women.

2.
Int J Mol Sci ; 24(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37762260

RESUMO

In cancer therapy, new therapeutic nanoformulations able to mediate targeted chemotherapy are required. Recently, biomimetic magnetic nanoparticles (BMNPs) mediated by MamC, a magnetosome protein from Magnetococcus marinus MC-1, have proven, in vitro and in vivo, to be effective drug nanocarriers (following the application of an external gradient magnetic field) and to allow combination with hyperthermia. However, these nanoassemblies require further optimization to improve cytocompatibility, stability and active targeting ability. Herein, we describe the production of the magnetoliposomes (LP) embedding BMNPs functionalized (or not) with doxorubicin (DOXO), [LP(+/-DOXO-BMNPs)], and their surface modification with the DO-24 mAb, which targets the human Met/HGF receptor's ectodomain (overexpressed in many cancers). Nanoformulations were extensively characterized using TEM, DLS, FTIR and when tested in vitro, the lipid coating increased the colloidal stability and their biocompatibility, favoring the cellular uptake in cells overexpressing the cognate receptor. Indeed, the magnetoliposomes mAb-LP(+/-DOXO-BMNPs) exerted a specific active targeting ability by the presence of the mAb that preserved its immunocompetence. Both LP(BMNPs) and mAb-LP(BMNPs) were not toxic to cells, while +/-mAb-LP(DOXO-BMNPs) nanoformulations were indeed cytotoxic. Therefore, this study represents a proof of concept for the development of promising drug carriers for cancer therapy based on local chemotherapy directed by mAbs.


Assuntos
Biomimética , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Anticorpos Monoclonais/farmacologia , Portadores de Fármacos , Transporte Biológico , Doxorrubicina/farmacologia , Neoplasias/tratamento farmacológico
3.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36768766

RESUMO

Cells of the cardiovascular system are physiologically exposed to a variety of mechanical forces fundamental for both cardiac development and functions. In this context, forces generated by actomyosin networks and those transmitted through focal adhesion (FA) complexes represent the key regulators of cellular behaviors in terms of cytoskeleton dynamism, cell adhesion, migration, differentiation, and tissue organization. In this study, we investigated the involvement of FAs on cardiomyocyte differentiation. In particular, vinculin and focal adhesion kinase (FAK) family, which are known to be involved in cardiac differentiation, were studied. Results revealed that differentiation conditions induce an upregulation of both FAK-Tyr397 and vinculin, resulting also in the translocation to the cell membrane. Moreover, the role of mechanical stress in contractile phenotype expression was investigated by applying a uniaxial mechanical stretching (5% substrate deformation, 1 Hz frequency). Morphological evaluation revealed that the cell shape showed a spindle shape and reoriented following the stretching direction. Substrate deformation resulted also in modification of the length and the number of vinculin-positive FAs. We can, therefore, suggest that mechanotransductive pathways, activated through FAs, are highly involved in cardiomyocyte differentiation, thus confirming their role during cytoskeleton rearrangement and cardiac myofilament maturation.


Assuntos
Adesões Focais , Adesões Focais/metabolismo , Vinculina/metabolismo , Adesão Celular/fisiologia , Membrana Celular/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Diferenciação Celular
4.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502309

RESUMO

Skeletal muscles represent 40% of body mass and its native regenerative capacity can be permanently lost after a traumatic injury, congenital diseases, or tumor ablation. The absence of physiological regeneration can hinder muscle repair preventing normal muscle tissue functions. To date, tissue engineering (TE) represents one promising option for treating muscle injuries and wasting. In particular, hydrogels derived from the decellularized extracellular matrix (dECM) are widely investigated in tissue engineering applications thanks to their essential role in guiding muscle regeneration. In this work, the myogenic potential of dECM substrate, obtained from decellularized bovine pericardium (Tissuegraft Srl), was evaluated in vitro using C2C12 murine muscle cells. To assess myotubes formation, the width, length, and fusion indexes were measured during the differentiation time course. Additionally, the ability of dECM to support myogenesis was assessed by measuring the expression of specific myogenic markers: α-smooth muscle actin (α-sma), myogenin, and myosin heavy chain (MHC). The results obtained suggest that the dECM niche was able to support and enhance the myogenic potential of C2C12 cells in comparison of those grown on a plastic standard surface. Thus, the use of extracellular matrix proteins, as biomaterial supports, could represent a promising therapeutic strategy for skeletal muscle tissue engineering.


Assuntos
Diferenciação Celular , Matriz Extracelular/fisiologia , Desenvolvimento Muscular , Mioblastos/citologia , Pericárdio/citologia , Engenharia Tecidual/métodos , Animais , Bovinos , Hidrogéis/química , Camundongos , Alicerces Teciduais/química
5.
Langmuir ; 34(45): 13713-13724, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30394747

RESUMO

New biomimetic magnetite nanoparticles (hereafter BMNPs) with sizes larger than most common superparamagnetic nanoparticles were produced in the presence of the recombinant MamC protein from Magnetococcus marinus MC-1 and functionalized with doxorubicin (DOXO) intended as potential drug nanocarriers. Unlike inorganic magnetite nanoparticles, in BMNPs the MamC protein controls their size and morphology, providing them with magnetic properties consistent with a large magnetic moment per particle; moreover, it provides the nanoparticles with novel surface properties. BMNPs display the isoelectric point at pH 4.4, being strongly negatively charged at physiological pH (pH 7.4). This allows both (i) their functionalization with DOXO, which is positively charged at pH 7.4, and (ii) the stability of the DOXO-surface bond and DOXO release to be pH dependent and governed by electrostatic interactions. DOXO adsorption follows a Langmuir-Freundlich model, and the coupling of DOXO to BMNPs (binary biomimetic nanoparticles) is very stable at physiological pH (maximum release of 5% of the drug adsorbed). Conversely, when pH decreases, these electrostatic interactions weaken, and at pH 5, DOXO is released up to ∼35% of the amount initially adsorbed. The DOXO-BMNPs display cytotoxicity on the GTL-16 human gastric carcinoma cell line in a dose-dependent manner, reaching about ∼70% of mortality at the maximum amount tested, while the nonloaded BMNPs are fully cytocompatible. The present data suggest that BMNPs could be useful as potential drug nanocarriers with a drug adsorption-release governed by changes in local pH values.


Assuntos
Proteínas de Bactérias/química , Materiais Biomiméticos/química , Doxorrubicina/química , Portadores de Fármacos/química , Nanopartículas de Magnetita/química , Adsorção , Alphaproteobacteria/química , Proteínas de Bactérias/toxicidade , Materiais Biomiméticos/toxicidade , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas de Magnetita/toxicidade , Tamanho da Partícula , Proteínas Recombinantes/química , Proteínas Recombinantes/toxicidade , Propriedades de Superfície
6.
Mol Ther ; 25(8): 1815-1830, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28552407

RESUMO

Hemophilia A (HA) is an X-linked bleeding disease caused by factor VIII (FVIII) deficiency. We previously demonstrated that FVIII is produced specifically in liver sinusoid endothelial cells (LSECs) and to some degree in myeloid cells, and thus, in the present work, we seek to restrict the expression of FVIII transgene to these cells using cell-specific promoters. With this approach, we aim to limit immune response in a mouse model by lentiviral vector (LV)-mediated gene therapy encoding FVIII. To increase the target specificity of FVIII expression, we included miRNA target sequences (miRTs) (i.e., miRT-142.3p, miRT-126, and miRT-122) to silence expression in hematopoietic cells, endothelial cells, and hepatocytes, respectively. Notably, we report, for the first time, therapeutic levels of FVIII transgene expression at its natural site of production, which occurred without the formation of neutralizing antibodies (inhibitors). Moreover, inhibitors were eradicated in FVIII pre-immune mice through a regulatory T cell-dependent mechanism. In conclusion, targeting FVIII expression to LSECs and myeloid cells by using LVs with cell-specific promoter minimized off-target expression and immune responses. Therefore, at least for some transgenes, expression at the physiologic site of synthesis can enhance efficacy and safety, resulting in long-term correction of genetic diseases such as HA.


Assuntos
Hemofilia A/genética , Hemofilia A/imunologia , Tolerância Imunológica/genética , Terapia de Imunossupressão , Animais , Antígeno CD11b/genética , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Fator VIII/genética , Fator VIII/imunologia , Fator VIII/metabolismo , Expressão Gênica , Genes Reporter , Vetores Genéticos/genética , Imunização , Terapia de Imunossupressão/métodos , Isoanticorpos/sangue , Isoanticorpos/imunologia , Lentivirus/genética , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/genética , Regiões Promotoras Genéticas , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Transdução Genética , Transgenes , Tempo de Coagulação do Sangue Total
7.
Am J Pathol ; 186(3): 539-51, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26773351

RESUMO

Kupffer cells (KC) play major roles in immunity and tissue injury or repair. Because recapitulation of KC biology and function within liver will allow superior insights into their functional repertoire, we studied the efficacy of the cell transplantation approach for this purpose. Mouse KC were isolated from donor livers, characterized, and transplanted into syngeneic recipients. To promote cell engraftment through impairments in native KC, recipients were preconditioned with gadolinium chloride. The targeting, fate, and functionality of transplanted cells were evaluated. The findings indicated that transplanted KC engrafted and survived in recipient livers throughout the study period of 3 months. Transplanted KC expressed macrophage functions, including phagocytosis and cytokine expression, with or without genetic modifications using lentiviral vectors. This permitted studies of whether transplanted KC could affect outcomes in the context of acetaminophen hepatotoxicity or hepatic ischemia-reperfusion injury. Transplanted KC exerted beneficial effects in these injury settings. The benefits resulted from cytoprotective factors including vascular endothelial growth factor. In conclusion, transplanted adult KC were successfully targeted and engrafted in the liver with retention of innate immune and tissue repair functions over the long term. This will provide excellent opportunities to address critical aspects in the biogenesis, fate, and function of KC within their native liver microenvironment and to develop the cell and gene therapy potential of KC transplantation.


Assuntos
Células de Kupffer/fisiologia , Células de Kupffer/transplante , Macrófagos/fisiologia , Traumatismo por Reperfusão/terapia , Acetaminofen/efeitos adversos , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Gadolínio , Terapia Genética , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/fisiologia , Fagocitose , Traumatismo por Reperfusão/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Haematologica ; 100(7): 881-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25911555

RESUMO

A large fraction of factor VIII in blood originates from liver sinusoidal endothelial cells although extrahepatic sources also contribute to plasma factor VIII levels. Identification of cell-types other than endothelial cells with the capacity to synthesize and release factor VIII will be helpful for therapeutic approaches in hemophilia A. Recent cell therapy and bone marrow transplantation studies indicated that Küpffer cells, monocytes and mesenchymal stromal cells could synthesize factor VIII in sufficient amount to ameliorate the bleeding phenotype in hemophilic mice. To further establish the role of blood cells in expressing factor VIII, we studied various types of mouse and human hematopoietic cells. We identified factor VIII in cells isolated from peripheral and cord blood, as well as bone marrow. Co-staining for cell type-specific markers verified that factor VIII was expressed in monocytes, macrophages and megakaryocytes. We additionally verified that factor VIII was expressed in liver sinusoidal endothelial cells and endothelial cells elsewhere, e.g., in the spleen, lungs and kidneys. Factor VIII was well expressed in sinusoidal endothelial cells and Küpffer cells isolated from human liver, whereas by comparison isolated human hepatocytes expressed factor VIII at very low levels. After transplantation of CD34(+) human cord blood cells into NOD/SCIDγNull-hemophilia A mice, fluorescence activated cell sorting of peripheral blood showed >40% donor cells engrafted in the majority of mice. In these animals, plasma factor VIII activity 12 weeks after cell transplantation was up to 5% and nine of 12 mice survived after a tail clip-assay. In conclusion, hematopoietic cells, in addition to endothelial cells, express and secrete factor VIII: this information should offer further opportunities for understanding mechanisms of factor VIII synthesis and replenishment.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Células Endoteliais/metabolismo , Fator VIII/biossíntese , Hemofilia A/terapia , Hemorragia/prevenção & controle , Células de Kupffer/metabolismo , Animais , Coagulação Sanguínea/genética , Modelos Animais de Doenças , Células Endoteliais/patologia , Fator VIII/genética , Fator VIII/metabolismo , Sangue Fetal/citologia , Sangue Fetal/metabolismo , Regulação da Expressão Gênica , Sobrevivência de Enxerto , Hemofilia A/sangue , Hemofilia A/genética , Hemofilia A/patologia , Hemorragia/sangue , Hemorragia/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Células de Kupffer/patologia , Fígado/metabolismo , Fígado/patologia , Megacariócitos/metabolismo , Megacariócitos/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Monócitos/metabolismo , Monócitos/patologia , Fenótipo , Transplante Heterólogo
9.
Langmuir ; 31(5): 1766-75, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25602940

RESUMO

Multifunctional biomimetic nanoparticles (NPs) are acquiring increasing interest as carriers in medicine and basic research since they can efficiently combine labels for subsequent tracking, moieties for specific cell targeting, and bioactive molecules, e.g., drugs. In particular, because of their easy synthesis, low cost, good biocompatibility, high resorbability, easy surface functionalization, and pH-dependent solubility, nanocrystalline apatites are promising candidates as nanocarriers. This work describes the synthesis and characterization of bioinspired apatite nanoparticles to be used as fluorescent nanocarriers targeted against the Met/hepatocyte growth factor receptor, which is considered a tumor associated cell surface marker of many cancers. To this aim the nanoparticles have been labeled with Fluorescein-5-isothiocyanate (FITC) by simple isothermal adsorption, in the absence of organic, possibly toxic, molecules, and then functionalized with a monoclonal antibody (mAb) directed against such a receptor. Direct labeling of the nanoparticles allowed tracking the moieties with spatiotemporal resolution and thus following their interaction with cells, expressing or not the targeted receptor, as well as their fate in vitro. Cytofluorometry and confocal microscopy experiments showed that the functionalized nanocarriers, which emitted a strong fluorescent signal, were rapidly and specifically internalized in cells expressing the receptor. Indeed, we found that, once inside the cells expressing the receptor, mAb-functionalized FITC nanoparticles partially dissociated in their two components, with some mAbs being recycled to the cell surface and the FITC-labeled nanoparticles remaining in the cytosol. This work thus shows that FITC-labeled nanoapatites are very promising probes for targeted cell imaging applications.


Assuntos
Anticorpos Monoclonais/química , Apatitas/química , Materiais Biomiméticos/química , Fluoresceína-5-Isotiocianato/química , Corantes Fluorescentes/química , Imagem Molecular/métodos , Nanopartículas/química , Anticorpos Monoclonais/imunologia , Transporte Biológico , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/metabolismo , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Humanos , Espaço Intracelular/metabolismo , Teste de Materiais , Proteínas Proto-Oncogênicas c-met/imunologia
10.
Bioorg Med Chem Lett ; 25(8): 1736-1741, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25800115
11.
BMJ Open ; 14(3): e076201, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38458783

RESUMO

INTRODUCTION: Pre-eclampsia affects ~5%-7% of pregnancies. Although improved obstetric care has significantly diminished its associated maternal mortality, it remains a leading cause of maternal morbidity and mortality in the world. Term pre-eclampsia accounts for 70% of all cases and a large proportion of maternal-fetal morbidity related to this condition. Unlike in preterm pre-eclampsia, the prediction and prevention of term pre-eclampsia remain unsolved. Previously proposed approaches are based on combined third-trimester screening and/or prophylactic drugs, but these policies are unlikely to be widely implementable in many world settings. Recent evidence shows that the soluble fms-like tyrosine kinase-1 (s-Flt-1) to placental growth factor (PlGF) ratio measured at 35-37 weeks' gestation predicts term pre-eclampsia with an 80% detection rate. Likewise, recent studies demonstrate that induction of labour beyond 37 weeks is safe and well accepted by women. We hypothesise that a single-step universal screening for term pre-eclampsia based on sFlt1/PlGF ratio at 35-37 weeks followed by planned delivery beyond 37 weeks reduces the prevalence of term pre-eclampsia without increasing the caesarean section rates or worsening the neonatal outcomes. METHODS AND ANALYSIS: We propose an open-label randomised clinical trial to evaluate the impact of a screening of term pre-eclampsia with the sFlt-1/PlGF ratio followed by planned delivery in asymptomatic nulliparous women at 35-37 weeks. Women will be assigned 1:1 to revealed (sFlt-1/PlGF known to clinicians) versus concealed (unknown) arms. A cut-off of >90th centile is used to define the high risk of subsequent pre-eclampsia and offer planned delivery from 37 weeks. The efficacy variables will be analysed and compared between groups primarily following an intention-to-treat approach, by ORs and their 95% CI. This value will be computed using a Generalised Linear Mixed Model for binary response (study group as fixed effect and the centre as intercept random effect). ETHICS AND DISSEMINATION: The study is conducted under the principles of Good Clinical Practice. This study was accepted by the Clinical Research Ethics Committee of Hospital Clinic Barcelona on 20 November 2020. Subsequent approval by individual ethical committees and competent authorities was granted. The study results will be published in peer-reviewed journals and disseminated at international conferences. TRIAL REGISTRATION NUMBER: NCT04766866.


Assuntos
Pré-Eclâmpsia , Recém-Nascido , Gravidez , Feminino , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/prevenção & controle , Pré-Eclâmpsia/epidemiologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fator de Crescimento Placentário , Cesárea , Biomarcadores , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
12.
Small ; 9(22): 3834-44, 2013 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-23606568

RESUMO

Nanosized drug carriers functionalized with moieties specifically targeting tumor cells are promising tools in cancer therapy, due to their ability to circulate in the bloodstream for longer periods and their selectivity for tumor cells, enabling the sparing of healthy tissues. Because of its biocompatibility, high bioresorbability, and responsiveness to pH changes, synthetic biomimetic nanocrystalline apatites are used as nanocarriers to produce multifunctional nanoparticles, by coupling them with the chemotherapeutic drug doxorubicin (DOXO) and the DO-24 monoclonal antibody (mAb) directed against the Met/Hepatocyte Growth Factor receptor (Met/HGFR), which is over-expressed on different types of carcinomas and thus represents a useful tumor target. The chemical-physical features of the nanoparticles are fully investigated and their interaction with cells expressing (GTL-16 gastric carcinoma line) or not expressing (NIH-3T3 fibroblasts) the Met/HGFR is analyzed. Functionalized nanoparticles specifically bind to and are internalized in cells expressing the receptor (GTL-16) but not in the ones that do not express it (NIH-3T3). Moreover they discharge DOXO in the targeted GTL-16 cells that reach the nucleus and display cytotoxicity as assessed in an MTT assay. Two different types of ternary nanoparticles are prepared, differing for the sequence of the functionalization steps (adsorption of DOXO first and then mAb or vice versa), and it is found that the ones in which mAb is adsorbed first are more efficient under all the examined aspects (binding, internalization, cytotoxicity), possibly because of a better mAb orientation on the nanoparticle surface. These multifunctional nanoparticles could thus be useful instruments for targeted local or systemic drug delivery, allowing a reduction in the therapeutic dose of the drug and thus adverse side effects. Moreover, this work opens new perspectives in the use of nanocrystalline apatites as a new platform for theranostic applications in nanomedicine.


Assuntos
Apatitas/química , Biomimética/métodos , Portadores de Fármacos/química , Nanopartículas/química , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Portadores de Fármacos/administração & dosagem , Humanos , Camundongos , Células NIH 3T3 , Nanopartículas/administração & dosagem
13.
Langmuir ; 29(26): 8213-21, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23735159

RESUMO

In this work, the efficiency of bioinspired citrate-functionalized nanocrystalline apatites as nanocarriers for delivery of doxorubicin (DOXO) has been assessed. The nanoparticles were synthesized by thermal decomplexing of metastable calcium/citrate/phosphate solutions both in the absence (Ap) and in the presence (cAp) of carbonate ions. The presence of citrate and carbonate ions in the solution allowed us to tailor the size, shape, carbonate content, and surface chemistry of the nanoparticles. The drug-loading efficiency of the two types of apatite was evaluated by means of the adsorption isotherms, which were found to fit a Langmuir-Freundlich behavior. A model describing the interaction between apatite surface and DOXO is proposed from adsorption isotherms and ζ-potential measurements. DOXO is adsorbed as a dimer by means of a positively charged amino group that electrostatically interacts with negatively charged surface groups of nanoparticles. The drug-release profiles were explored at pHs 7.4 and 5.0, mimicking the physiological pH in the blood circulation and the more acidic pH in the endosome-lysosome intracellular compartment, respectively. After 7 days at pH 7.4, cAp-DOXO released around 42% less drug than Ap-DOXO. However, at acidic pH, both nanoassemblies released similar amounts of DOXO. In vitro assays analyzed by confocal microscopy showed that both drug-loaded apatites were internalized within GTL-16 human carcinoma cells and could release DOXO, which accumulated in the nucleus in short times and exerted cytotoxic activity with the same efficiency. cAp are thus expected to be a more promising nanocarrier for experiments in vivo, in situations where intravenous injection of nanoparticles are required to reach the targeted tumor, after circulating in the bloodstream.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Apatitas/química , Citrato de Cálcio/química , Carbonatos/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Nanopartículas/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Composição de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Eletricidade Estática , Termodinâmica
14.
Gynecol Endocrinol ; 29(7): 632-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23772774

RESUMO

Oocyte donation can satisfy the desire to have children in women with premature ovarian failure (POF) but little progress has been made to improve reproduction using the patients' own gametes. The aim of this study was to assess the effectiveness of alternative treatments to oocyte donation in patients with POF. A systematic search of MEDLINE, EMBASE and Cochrane databases from January 1988 to January 2012 using descriptors related to POF, ovulation induction, and pregnancy was made. Randomized clinical trials of women with POF undergoing various treatments to achieve ovulation induction, often compared with alternative treatment and placebo groups, were only selected. Outcomes of interest were those related to pregnancy (biochemical and live birth). Twelve trials were included and analysed for methodology, inclusion and exclusion criteria, number of patients included, characteristics and type of intervention, and results in terms of ovulation rate, pregnancy rate and ongoing pregnancy rate. The large methodological variability among studies prevented to combined data for a meta-analysis. None of the studies showed statistically significant differences between the study groups. The lack of case-control studies with a placebo group makes it impossible to establish differences between a treatment and no treatment.


Assuntos
Doação de Oócitos , Indução da Ovulação/métodos , Insuficiência Ovariana Primária/terapia , Ensaios Clínicos como Assunto/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Doação de Oócitos/estatística & dados numéricos , Gravidez , Taxa de Gravidez , Insuficiência Ovariana Primária/complicações , Insuficiência Ovariana Primária/epidemiologia
15.
Pharmaceutics ; 15(6)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37376159

RESUMO

New therapeutic strategies are required in cancer therapy. Considering the prominent role of tumor-associated macrophages (TAMs) in the development and progression of cancer, the re-education of TAMs in the tumor microenvironment (TME) could represent a potential approach for cancer immunotherapy. TAMs display an irregular unfolded protein response (UPR) in their endoplasmic reticulum (ER) to endure environmental stress and ensure anti-cancer immunity. Therefore, nanotechnology could be an attractive tool to modulate the UPR in TAMs, providing an alternative strategy for TAM-targeted repolarization therapy. Herein, we developed and tested polydopamine-coupled magnetite nanoparticles (PDA-MNPs) functionalized with small interfering RNAs (siRNA) to downregulate the protein kinase R (PKR)-like ER kinase (PERK) expression in TAM-like macrophages derived from murine peritoneal exudate (PEMs). After the evaluation of the cytocompatibility, the cellular uptake, and the gene silencing efficiency of PDA-MNPs/siPERK in PEMs, we analyzed their ability to re-polarize in vitro these macrophages from M2 to the M1 inflammatory anti-tumor phenotype. Our results indicate that PDA-MNPs, with their magnetic and immunomodulator features, are cytocompatible and able to re-educate TAMs toward the M1 phenotype by PERK inhibition, a UPR effector contributing to TAM metabolic adaptation. These findings can provide a novel strategy for the development of new tumor immunotherapies in vivo.

16.
Stem Cells ; 29(12): 2051-61, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22009661

RESUMO

Human heart harbors a population of resident progenitor cells that can be isolated by stem cell antigen-1 antibody and expanded in culture. These cells can differentiate into cardiomyocytes in vitro and contribute to cardiac regeneration in vivo. However, when directly injected as single cell suspension, less than 1%-5% survive and differentiate. Among the major causes of this failure are the distressing protocols used to culture in vitro and implant progenitor cells into damaged hearts. Human cardiac progenitors obtained from the auricles of patients were cultured as scaffoldless engineered tissues fabricated using temperature-responsive surfaces. In the engineered tissue, progenitor cells established proper three-dimensional intercellular relationships and were embedded in self-produced extracellular matrix preserving their phenotype and multipotency in the absence of significant apoptosis. After engineered tissues were leant on visceral pericardium, a number of cells migrated into the murine myocardium and in the vascular walls, where they integrated in the respective textures. The study demonstrates the suitability of such an approach to deliver stem cells to the myocardium. Interestingly, the successful delivery of cells in murine healthy hearts suggests that myocardium displays a continued cell cupidity that is strictly regulated by the limited release of progenitor cells by the adopted source. When an unregulated cell source is added to the system, cells are delivered to the myocardium. The exploitation of this novel concept may pave the way to the setup of new protocols in cardiac cell therapy.


Assuntos
Ventrículos do Coração/transplante , Miocárdio/metabolismo , Miócitos Cardíacos/citologia , Células-Tronco/citologia , Engenharia Tecidual/métodos , Idoso , Idoso de 80 Anos ou mais , Animais , Diferenciação Celular , Movimento Celular , Técnicas de Cocultura , Feminino , Perfilação da Expressão Gênica , Ventrículos do Coração/citologia , Ventrículos do Coração/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Miocárdio/citologia , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/transplante , Fenótipo , Transplante de Tecidos/métodos
17.
Can J Physiol Pharmacol ; 90(3): 317-25, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22364544

RESUMO

Direct reprogramming of somatic cells into pluripotent cells is an emerging technology for creating patient-specific cells, and potentially opens new scenarios in medical and pharmacological fields. From the discovery of Shinya Yamanaka, who first obtained pluripotent cells from fibroblasts by retrovirus-derived ectopic expression of defined embryonic transcription factors, new methods have been developed to generate safe induced pluripotent stem (iPS) cells without genomic manipulations. This review will focus on the recent advances in iPS technology and their application in pharmacology and medicine.


Assuntos
Células-Tronco Pluripotentes Induzidas/transplante , Adenoviridae/genética , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , MicroRNAs/genética , Plasmídeos
18.
J Sep Sci ; 35(16): 2048-53, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22778021

RESUMO

An analytical method for the analysis of six fluoroquinolones (FQs) in animal feeds was developed. The sample treatment consists of a simple and rapid extraction of the analytes by manual shaking with an acetonitrile-water mixture containing hydrochloric acid without further sample cleanup. Matrix effects were minimized by diluting the extract with water. Determination was carried out by liquid chromatography using fluorimetric detection. The method was validated in-house in four different feed matrices (poultry, cow, pig, and lamb feed). Mean recoveries ranging from 80 to 105%, with relative standard deviations below 12%, were achieved from spiked animal feed samples on the 0.2-2.0 µg/g level. No relevant differences were observed between the studied feeds, this ensuring that the method was reliable for a wide variety of feed matrices. Decision limit and detection capability values are below 0.08 and 0.13 mg/kg, respectively, for most FQs. The results obtained demonstrate the feasibility of the analytical method developed for a routine use to control the illegal use of these substances in feeding stuffs.


Assuntos
Ração Animal/análise , Cromatografia Líquida/métodos , Fluoroquinolonas/análise , Espectrometria de Fluorescência/métodos
19.
J Mater Sci Mater Med ; 23(5): 1291-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22391994

RESUMO

Highly soluble amorphous calcium phosphate powder (ACP) was added to the alginate gel as a buffering agent, in an attempt to enable widely controlled release while avoiding an acidification of the gel-environment. Therapeutic effects of the ACP-containing alginate gel which slowly releases a drug, simvastatin, on osteoporosis model rats were examined. A model drug, simvastatin, incorporated in the alginate gel with ACP up to 0.5%, was continuously released for a long time under the acidic condition. The release rate was controlled by the amount of ACP, serving as a buffer to suppress acidity. When the alginate solution intramuscularly injected in the rat, a soft gel was formed in the injected site. Simvastatin released from the gel containing 0.5% of ACP showed high therapeutic effect on osteoporosis rat. Thus, the present injectable long-sustained release system is expected to be a novel drug delivery controlling device.


Assuntos
Alginatos/síntese química , Fosfatos de Cálcio/administração & dosagem , Osteoporose/tratamento farmacológico , Sinvastatina/administração & dosagem , Alginatos/administração & dosagem , Alginatos/química , Animais , Soluções Tampão , Fosfatos de Cálcio/química , Catálise , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Modelos Animais de Doenças , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Feminino , Géis/administração & dosagem , Géis/síntese química , Géis/química , Hipolipemiantes/administração & dosagem , Hipolipemiantes/química , Injeções , Osteoporose/patologia , Polimerização , Ratos , Ratos Sprague-Dawley , Sinvastatina/química
20.
J Mater Sci Mater Med ; 23(11): 2659-69, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22864504

RESUMO

In this paper, hybrid inorganic-organic core-shell hollow microspheres, made of poly(L-lactic acid) (PLLA) and biomimetic nano apatites (HA), were prepared from biodegradable and biocompatible substances, suitable for bone tissue applications. Preparation is started from Pickering emulsification, i.e., solid particle-stabilized emulsions in the absence of any molecular surfactant, where solid particles adsorbed to an oil-water interface. Stable oil-in-water emulsions were produced using biomimetic 20 nm sized HA nanocrystals as particulate emulsifier and a dichloromethane (CH(2)Cl(2)) solution of PLLA as oil phase. Hybrid hollow PLLA microspheres at three different HA nanocrystals surface coverage, ranging from 10 to 50 µm, were produced. The resulting materials were completely characterized with spectroscopic, calorimetric and microscopic techniques and the cytocompatibility was established by indirect contact tests with both fibroblasts and osteoblasts and direct contact with these latter. They displayed a high level of cytocompatibility and thus represent promising materials for drug delivery systems, cell carriers and scaffolds for regeneration of bone useful in the treatment of orthopaedic, maxillofacial and dental fields.


Assuntos
Materiais Biocompatíveis , Substitutos Ósseos , Ácido Láctico/química , Microesferas , Polímeros/química , Varredura Diferencial de Calorimetria , Células Cultivadas , Cristalização , Imunofluorescência , Humanos , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Tamanho da Partícula , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual , Difração de Raios X
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