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1.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36834912

RESUMO

MPM has a uniquely poor somatic mutational landscape, mainly driven by environmental selective pressure. This feature has dramatically limited the development of effective treatment. However, genomic events are known to be associated with MPM progression, and specific genetic signatures emerge from the exceptional crosstalk between neoplastic cells and matrix components, among which one main area of focus is hypoxia. Here we discuss the novel therapeutic strategies focused on the exploitation of MPM genetic asset and its interconnection with the surrounding hypoxic microenvironment as well as transcript products and microvesicles representing both an insight into the pathogenesis and promising actionable targets.


Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Humanos , Mesotelioma/patologia , Simulação de Dinâmica Molecular , Secretoma , Neoplasias Pleurais/patologia , Neoplasias Pulmonares/genética , Microambiente Tumoral
2.
Lancet Oncol ; 23(5): 671-681, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35427469

RESUMO

BACKGROUND: The optimal duration of androgen deprivation combined with high-dose radiotherapy in prostate cancer remains controversial. The DART 01/05 trial was designed to determine whether long-term androgen deprivation is superior to short-term androgen deprivation when combined with high-dose radiotherapy. The 5-year results showed that 2 years of adjuvant androgen deprivation combined with high-dose radiotherapy significantly improved biochemical control, metastasis, and overall survival, especially in patients with high-risk disease. In this report, we present the 10-year final results of the trial. METHODS: This open-label, phase 3, randomised, controlled trial was done in ten hospitals in Spain. The eligibility criteria included patients aged 18 years or older with histologically confirmed T1c to T3, N0, and M0 adenocarcinoma of the prostate, according to the 2002 classification of the American Joint Committee on Cancer, with intermediate-risk and high-risk factors, prostate-specific antigen (PSA) less than 100 ng/mL, and a Karnofsky performance score of at least 70%. Patients were randomly assigned (1:1) to receive 4 months of neoadjuvant and concomitant short-term androgen deprivation (STAD) plus high-dose radiotherapy (minimum dose 76 Gy; median dose 78 Gy) or to receive the same treatment followed by 24 months of adjuvant long-term androgen deprivation (LTAD), via a randomisation scheduled generated by Statistical Analysis Software programme (version 9.1) and an interactive web response system. Patients assigned to the STAD group received 4 months of neoadjuvant and concomitant androgen deprivation (oral flutamide 750 mg per day or oral bicalutamide 50 mg per day) with subcutaneous goserelin (2 months before and 2 months combined with high-dose radiotherapy). Anti-androgen therapy was added during the first 2 months of treatment. Patients assigned to LTAD continued with goserelin every 3 months for another 24 months. The primary endpoint was biochemical disease-free survival at 5 years. For this 10-year study we analysed overall survival, metastasis-free survival, biochemical disease-free survival, and cause-specific survival. Analysis was by intention to treat. This trial is closed and is registered at ClinicalTrials.gov (NCT02175212) and in the EU Clinical Trials Register (EudraCT 2005-000417-36). FINDINGS: Between Nov 7, 2005, and Dec 20, 2010, 355 patients were enrolled. One patient in the STAD group withdrew from the trial, hence 354 participants were randomly assigned to STAD (n=177) or LTAD (n=177). The median follow-up was 119·4 months (IQR 100·6-124·3). The 10-year biochemical disease-free survival for LTAD was 70·2% (95% CI 63·1-77·3) and for STAD was 62·3% (54·9-69·7; hazard ratio [HR] 0·84; 95% CI 0·50-1·43; p=0·52). At 10 years, overall survival was 78·4% (72·1-84·8) for LTAD and 73·3% (66·6-80·0) for STAD (HR 0·84; 95% CI 0·55-1·27; p=0·40), and metastasis-free survival was 76·0% (69·4-82·7) for LTAD and 70·9% (64·0-77·8) for STAD (HR 0·90; 95% CI, 0·37-2·19; p=0·81). For the subgroup of high-risk patients, the 10-year biochemical disease-free survival was 67·2% (57·2-77·2) for LTAD and 53·7% (43·3-64·1) for STAD (HR 0·90; 95% CI 0·49-1·64; p=0·73), the 10-year overall survival was 78·5% (69·6-87·3) for LTAD and 67·0% (57·3-76·7) for STAD (HR 0·58; 95% CI 0·33-1·01; p=0·054), and the 10-year metastasis-free survival was 76·6% (95% CI 67·6-85·6) for LTAD and 65·0% (55·1-74·8) for STAD (HR 0·89; 95% CI 0·33-2·43; p=0·82). Only 11 (3%) of 354 patients died from prostate cancer, all of them in the high-risk subgroup (five in the LTAD group and six in the STAD group). 76 (21%) patients died from other causes (mainly second malignancies in 31 [9%] and cardiovascular disease in 21 [6%]). No treatment-related deaths were observed. INTERPRETATION: After an extended 10-year follow-up, we were unable to support the significant benefit of LTAD reported at 5 years. However, the magnitude of the benefit was clinically relevant in high-risk patients. Intermediate-risk patients treated with high-dose radiotherapy do not benefit from LTAD. A biological characterisation with the inclusion of genomic testing is needed in the decision-making process. FUNDING: Grupo de Investigación en Oncología Radioterápica and Sociedad Española de Oncología Radioterápica, the National Health Investigation Fund, and AstraZeneca.


Assuntos
Neoplasias da Próstata , Antagonistas de Androgênios/efeitos adversos , Androgênios , Gosserrelina , Humanos , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia
3.
Int J Mol Sci ; 23(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35457134

RESUMO

Recently, we proposed a Good Manufacturing Practice (GMP)-compliant production process for freeze-dried mesenchymal stem cell (MSC)-secretome (lyo-secretome): after serum starvation, the cell supernatant was collected, and the secretome was concentrated by ultrafiltration and freeze-dried, obtaining a standardized ready-to-use and stable powder. In this work, we modified the type of human platelet lysate (HPL) used as an MSC culture supplement during the lyo-secretome production process: the aim was to verify whether this change had an impact on product quality and also whether this new procedure could be validated according to GMP, proving the process robustness. MSCs were cultured with two HPLs: the standard previously validated one (HPL-E) and the new one (HPL-S). From the same pool of platelets, two batches of HPL were obtained: HPL-E (by repeated freezing and thawing cycles) and HPL-S (by adding Ca-gluconate to form a clot and its subsequent mechanical wringing). Bone marrow MSCs from three donors were separately cultured with the two HPLs until the third passage and then employed to produce lyo-secretome. The following indicators were selected to evaluate the process performance: (i) the lyo-secretome quantitative composition (in lipids and proteins), (ii) the EVs size distribution, and (iii) anti-elastase and (iv) immunomodulant activity as potency tests. The new HPL supplementation for MSCs culture induced only a few minimal changes in protein/lipid content and EVs size distribution; despite this, it did not significantly influence biological activity. The donor intrinsic MSCs variability in secretome secretion instead strongly affected the quality of the finished product and could be mitigated by concentrating the final product to reach a determined protein (and lipid) concentration. In conclusion, the modification of the type of HPL in the MSCs culture during lyo-secretome production induces only minimal changes in the composition but not in the potency, and therefore, the new procedure can be validated according to GMP.


Assuntos
Células-Tronco Mesenquimais , Ultrafiltração , Plaquetas/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Lipídeos , Células-Tronco Mesenquimais/metabolismo , Secretoma
4.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33920046

RESUMO

SmartBone® (SB) is a biohybrid bone substitute advantageously proposed as a class III medical device for bone regeneration in reconstructive surgeries (oral, maxillofacial, orthopedic, and oncology). In the present study, a new strategy to improve SB osteoinductivity was developed. SB scaffolds were loaded with lyosecretome, a freeze-dried formulation of mesenchymal stem cell (MSC)-secretome, containing proteins and extracellular vesicles (EVs). Lyosecretome-loaded SB scaffolds (SBlyo) were prepared using an absorption method. A burst release of proteins and EVs (38% and 50% after 30 min, respectively) was observed, and then proteins were released more slowly with respect to EVs, most likely because they more strongly adsorbed onto the SB surface. In vitro tests were conducted using adipose tissue-derived stromal vascular fraction (SVF) plated on SB or SBlyo. After 14 days, significant cell proliferation improvement was observed on SBlyo with respect to SB, where cells filled the cavities between the native trabeculae. On SB, on the other hand, the process was still present, but tissue formation was less organized at 60 days. On both scaffolds, cells differentiated into osteoblasts and were able to mineralize after 60 days. Nonetheless, SBlyo showed a higher expression of osteoblast markers and a higher quantity of newly formed trabeculae than SB alone. The quantification analysis of the newly formed mineralized tissue and the immunohistochemical studies demonstrated that SBlyo induces bone formation more effectively. This osteoinductive effect is likely due to the osteogenic factors present in the lyosecretome, such as fibronectin, alpha-2-macroglobulin, apolipoprotein A, and TGF-ß.


Assuntos
Matriz Óssea/química , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Transplante de Células-Tronco Mesenquimais , Animais , Substitutos Ósseos/química , Bovinos , Diferenciação Celular/efeitos dos fármacos , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Vesículas Extracelulares/química , Vesículas Extracelulares/genética , Humanos , Células-Tronco Mesenquimais/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Procedimentos de Cirurgia Plástica/métodos
5.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445150

RESUMO

Titanium is one of the most frequently used materials in bone regeneration due to its good biocompatibility, excellent mechanical properties, and great osteogenic performance. However, osseointegration with host tissue is often not definite, which may cause implant failure at times. The present study investigates the capacity of the mesenchymal stem cell (MSC)-secretome, formulated as a ready-to-use and freeze-dried medicinal product (the Lyosecretome), to promote the osteoinductive and osteoconductive properties of titanium cages. In vitro tests were conducted using adipose tissue-derived MSCs seeded on titanium cages with or without Lyosecretome. After 14 days, in the presence of Lyosecretome, significant cell proliferation improvement was observed. Scanning electron microscopy revealed the cytocompatibility of titanium cages: the seeded MSCs showed a spread morphology and an initial formation of filopodia. After 7 days, in the presence of Lyosecretome, more frequent and complex cellular processes forming bridges across the porous surface of the scaffold were revealed. Also, after 14 and 28 days of culturing in osteogenic medium, the amount of mineralized matrix detected by alizarin red was significantly higher when Lyosecretome was used. Finally, improved osteogenesis with Lyosecretome was confirmed by confocal analysis after 28 and 56 days of treatment, and demonstrating the production by osteoblast-differentiated MSCs of osteocalcin, a specific bone matrix protein.


Assuntos
Regeneração Óssea , Substitutos Ósseos/química , Células-Tronco Mesenquimais/citologia , Titânio/química , Proliferação de Células , Células Cultivadas , Liofilização , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Alicerces Teciduais/química
6.
Environ Geochem Health ; 41(5): 1909-1921, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30701355

RESUMO

Aljustrel mining area (South Portugal) is a part of the Iberian Pyrite Belt and encloses six sulfide mineral masses. This mine is classified of high environmental risk due to the large tailings' volume and acid mine drainage (AMD)-affected waters generated by sulfides' oxidation. The use of biological indicators (e.g., diatoms) revealed to be an important tool to address the degree of AMD contamination in waters. Multivariate analysis has been used as a relevant approach for the characterization of AMD processes. Cluster analysis was used to integrate the significant amount and diversity of variables (physicochemical and biological), discriminating the different types of waters, characterized by the high complexity occurring in this region. The distinction of two main marked phenomena was achieved: (1) the circumneutral-Na-Cl water type (sites DA, PF, BX, BF, RO, CB), expressing the geological contributions of the Cenozoic sediments of Sado river basin, with high diatom diversity (predominating brackish diatoms as Entomoneis alata); and (2) the acid-metal-sulfated water type (sites BM, JU, RJ, AA, MR, BE, PC, AF), reflecting both the AMD contamination and the dissolution of minerals (e.g., silicates) from the hosting rocks, potentiated by the extremely low pH. This last group of sites showed lower diatom diversity but with typical diatoms from acid- and metal-contaminated waters (e.g., Pinnularia aljustrelica). In addition to these two water types, this hierarchical classification method also allowed to distinguish individual cases in subclusters, for example, treated dams (DC, DD), with alkaline substances (lime/limestone), that changed the physicochemical dynamics of the contaminated waters.


Assuntos
Diatomáceas/fisiologia , Monitoramento Ambiental , Mineração , Rios/química , Poluentes Químicos da Água/análise , Ácidos/análise , Diatomáceas/classificação , Diatomáceas/crescimento & desenvolvimento , Ferro/análise , Metais/análise , Minerais/análise , Portugal , Sulfetos/análise
7.
Soft Matter ; 14(4): 546-557, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29327746

RESUMO

Silk proteins have been studied and employed for the production of drug delivery (nano)systems. They show excellent biocompatibility, controllable biodegradability and non-immunogenicity and, if needed, their properties can be modulated by blending with other polymers. Silk fibroin (SF), which forms the inner core of silk, is a (bio)material officially recognized by the Food and Drug Administration for human applications. Conversely, the potential of silk sericin (SS), which forms the external shell of silk, could still be considered under evaluation. At the best of our knowledge, nanoparticles based on silk sericin "alone" cannot be produced, due to its physicochemical instability influenced by extreme pH, high water solubility and temperature; for these reasons, it almost always needs to be combined with other polymers for the development of drug delivery systems. In this review, we focused on silk proteins as bioactive natural carriers, since they show not only optimal features as inert excipients, but also remarkable intrinsic biological activities. SF has anti-inflammatory properties, while SS presents antioxidant, anti-tyrosine, anti-aging, anti-elastase and anti-bacterial features. Here, we give an overview on SF or SS silk-based nanosystems, with particular attention on the production techniques.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Seda/química , Animais , Ensaios Clínicos como Assunto , Fibroínas/química , Humanos , Sericinas/química
8.
Nanomedicine ; 13(3): 1245-1254, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28115254

RESUMO

Here, long-circulating behaviors of Inulin-based nanomicelles are demonstrated for the first time in vivo. We show the synthesis and evaluation of biotin (BIO)-decorated polymeric INVITE micelles constituted of substances of natural origin, Inulin (INU) and Vitamin E (VITE), as long-circulating carriers for receptor-mediated targeted drug delivery. The resulting INVITE or INVITE-BIO micelles, nanometrically sized, did not reveal any cytotoxicity after 24h of incubation with Caco-2 cells. Moreover, in vitro studies on Caco-2 cells monolayers indicated that the transport of INVITE-BIO micelles was faster than surface unmodified INVITE micelles. In vivo optical imaging studies evidenced that, upon intravenous administration, INVITE-BIO micelles were quantitatively present in the body up to 48h. Instead, after oral administration, the micelles were not found in the systemic circulation but eliminated with the normal intestinal content. In conclusion, INVITE-BIO micelles may enhance drug accumulation in tumor-cells over-expressing the receptor for biotin through receptor mediated endocytosis.


Assuntos
Biotina/farmacocinética , Portadores de Fármacos/farmacocinética , Inulina/farmacocinética , Micelas , Vitamina E/farmacocinética , Animais , Biotina/química , Células CACO-2 , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Inulina/química , Camundongos Endogâmicos BALB C , Imagem Óptica , Vitamina E/química
9.
Int J Mol Sci ; 18(9)2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28832547

RESUMO

The aim of this study was to exploit silk fibroin's properties to develop innovative composite microcarriers for mesenchymal stem cell (MSCs) adhesion and proliferation. Alginate microcarriers were prepared, added to silk fibroin solution, and then treated with ethanol to induce silk conformational transition. Microcarriers were characterized for size distribution, coating stability and homogeneity. Finally, in vitro cytocompatibility and suitability as delivery systems for MSCs were investigated. Results indicated that our manufacturing process is consistent and reproducible: silk/alginate microcarriers were stable, with spherical geometry, about 400 µm in average diameter, and fibroin homogeneously coated the surface. MSCs were able to adhere rapidly onto the microcarrier surface and to cover the surface of the microcarrier within three days of culture; moreover, on this innovative 3D culture system, stem cells preserved their metabolic activity and their multi-lineage differentiation potential. In conclusion, silk/alginate microcarriers represent a suitable support for MSCs culture and expansion. Since it is able to preserve MSCs multipotency, the developed 3D system can be intended for cell delivery, for advanced therapy and regenerative medicine applications.


Assuntos
Alginatos/química , Fibroínas/química , Regeneração Tecidual Guiada/métodos , Células-Tronco Mesenquimais/fisiologia , Microesferas , Transplante de Células-Tronco/métodos , Adulto , Alginatos/efeitos adversos , Animais , Bombyx/química , Adesão Celular , Proliferação de Células , Células Cultivadas , Feminino , Fibroínas/efeitos adversos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos
10.
Pharm Dev Technol ; 21(4): 453-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25757645

RESUMO

With the aim of establishing the formulation of a new hydrophilic auto-gelling medical device for biomedical applications, fibroin-based microspheres were prepared. The proposed microspheres were produced by a cost-effective and industrially scalable technique, such as the spray-drying. Spray-dried silk fibroin microspheres were obtained and the effects of different hydrophilic polymer on the process yield, microsphere morphology and conformation transition of fibroin were evaluated. The final auto-gelling formulations were obtained by adding calcium gluconate (as a calcium source for alginate crosslinking) to the prepared microspheres and tested by an in vitro gelling test. This study showed that the combination of fibroin with sodium alginate and poloxamer produced the most promising auto-gelling formulation for specific biomedical applications, such as the treatment of pressure ulcers.


Assuntos
Alginatos/química , Bombyx/química , Gluconato de Cálcio/química , Fibroínas/química , Géis/química , Poloxâmero/química , Polietilenoglicóis/química , Animais , Dessecação , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Microesferas , Tamanho da Partícula , Pós/química
11.
Lancet Oncol ; 16(3): 320-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25702876

RESUMO

BACKGROUND: The optimum duration of androgen deprivation combined with high-dose radiotherapy in prostate cancer remains undefined. We aimed to determine whether long-term androgen deprivation was superior to short-term androgen deprivation when combined with high-dose radiotherapy. METHODS: In this open-label, multicentre, phase 3 randomised controlled trial, patients were recruited from ten university hospitals throughout Spain. Eligible patients had clinical stage T1c-T3b N0M0 prostate adenocarcinoma with intermediate-risk and high-risk factors according to 2005 National Comprehensive Cancer Network criteria. Patients were randomly assigned (1:1) using a computer-generated randomisation schedule to receive either 4 months of androgen deprivation combined with three-dimensional conformal radiotherapy at a minimum dose of 76 Gy (range 76-82 Gy; short-term androgen deprivation group) or the same treatment followed by 24 months of adjuvant androgen deprivation (long-term androgen deprivation group), stratified by prostate cancer risk group (intermediate risk vs high risk) and participating centre. Patients assigned to the short-term androgen deprivation group received 4 months of neoadjuvant and concomitant androgen deprivation with subcutaneous goserelin (2 months before and 2 months combined with high-dose radiotherapy). Anti-androgen therapy (flutamide 750 mg per day or bicalutamide 50 mg per day) was added during the first 2 months of treatment. Patients assigned to long-term suppression continued with the same luteinising hormone-releasing hormone analogue every 3 months for another 24 months. The primary endpoint was biochemical disease-free survival. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT02175212. FINDINGS: Between Nov 7, 2005, and Dec 20, 2010, 178 patients were randomly assigned to receive short-term androgen deprivation and 177 to receive long-term androgen deprivation. After a median follow-up of 63 months (IQR 50-82), 5-year biochemical disease-free survival was significantly better among patients receiving long-term androgen deprivation than among those receiving short-term treatment (90% [95% CI 87-92] vs 81% [78-85]; hazard ratio [HR] 1·88 [95% CI 1·12-3·15]; p=0·01). 5-year overall survival (95% [95% CI 93-97] vs 86% [83-89]; HR 2·48 [95% CI 1·31-4·68]; p=0·009) and 5-year metastasis-free survival (94% [95% CI 92-96] vs 83% [80-86]; HR 2·31 [95% CI 1·23-3·85]; p=0·01) were also significantly better in the long-term androgen deprivation group than in the short-term androgen deprivation group. The effect of long-term androgen deprivation on biochemical disease-free survival, metastasis-free survival, and overall survival was more evident in patients with high-risk disease than in those with low-risk disease. Grade 3 late rectal toxicity was noted in three (2%) of 177 patients in the long-term androgen deprivation group and two (1%) of 178 in the short-term androgen deprivation group; grade 3-4 late urinary toxicity was noted in five (3%) patients in each group. No deaths related to treatment were reported. INTERPRETATION: Compared with short-term androgen deprivation, 2 years of adjuvant androgen deprivation combined with high-dose radiotherapy improved biochemical control and overall survival in patients with prostate cancer, particularly those with high-risk disease, with no increase in late radiation toxicity. Longer follow-up is needed to determine whether men with intermediate-risk disease benefit from more than 4 months of androgen deprivation. FUNDING: Spanish National Health Investigation Fund, AstraZeneca.


Assuntos
Adenocarcinoma/terapia , Antagonistas de Androgênios/administração & dosagem , Antineoplásicos Hormonais/administração & dosagem , Quimiorradioterapia/métodos , Neoplasias da Próstata/terapia , Dosagem Radioterapêutica , Radioterapia Conformacional , Adenocarcinoma/secundário , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Androgênios/efeitos adversos , Anilidas/administração & dosagem , Antineoplásicos Hormonais/efeitos adversos , Quimiorradioterapia/efeitos adversos , Intervalo Livre de Doença , Esquema de Medicação , Flutamida/administração & dosagem , Hormônio Liberador de Gonadotropina/administração & dosagem , Hospitais Universitários , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nitrilas/administração & dosagem , Neoplasias da Próstata/patologia , Radioterapia Conformacional/efeitos adversos , Fatores de Risco , Espanha , Fatores de Tempo , Compostos de Tosil/administração & dosagem , Resultado do Tratamento
12.
Pituitary ; 17(3): 257-66, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23807201

RESUMO

BACKGROUND: Acromegalic patients have a higher risk of developing colorectal tumours (CRT). The common C677T polymorphism in methylenetetrahydrofolate reductase (MTHFR) gene is a well-documented CRT risk factor in the general population, but its role in acromegaly has never been examined. PURPOSE: We investigated the influence of MTHFR C677T polymorphism, folate status and other lifestyle, nutritional and disease-specific variables on CRT risk in acromegaly. METHODS: Clinical data were collected from 115 acromegalic patients (25 with active disease) who underwent a complete colonoscopy. C677T MTHFR genotype, homocysteine, vitamin B12, insulin growth factor and insulin levels, as well as metabolic variables were evaluated. RESULTS: Colorectal tumours were identified in 51 patients (3 adenocarcinomas). MTHFR C677T distribution was in the Hardy-Weinberg equilibrium and similar in patients with or without CRT. There was a correlation between patients with TT genotype and CRT occurrence (Spearman's test: P = 0.03), with an Odds Ratio (OR) of 1.32 (95% CI 0.522-3.362, P NS). A folate-MTHFR genotype interaction on CRT risk was found (P = 0.037): in the lower folate subgroup, TT patients showed a 2.4 higher OR for CRT (95% CI 0.484-11.891; P NS) than C-allele carriers. Smoking (P = 0.007), increased HbA1c levels (P = 0.021), dyslipidaemia (P = 0.049), acromegaly control (P = 0.057), and folate-MTHFR genotype interaction (P = 0.088) were associated with CRT at multivariate analysis. CONCLUSIONS: In this cohort of acromegalic patients, CRT risk is increased in 677TT MTHFR patients with low plasma folate levels. Smoking, high HbA1c levels, dyslipidaemia and disease activity were also associated with increased CRT risk.


Assuntos
Acromegalia/complicações , Acromegalia/genética , Neoplasias do Colo/epidemiologia , Neoplasias do Colo/genética , Ácido Fólico/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/complicações , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Mutação/genética , Estado Nutricional , Hormônios Hipofisários/sangue , Polimorfismo Genético/genética , Prevalência , Risco
13.
Pharm Dev Technol ; 19(1): 65-72, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23301945

RESUMO

Extracts of Crataegus monogyna Jacq. (hawthorn) show an interesting free radical scavenging (FRS) effect, related to their flavonoids content. Unfortunately, their oral administration is affected by their low bioavailability. The aim of this work is to obtain a multiparticulate drug delivery system for hawthorn extracts for oral administration. The extracts from flowering tops (FL) or fruits (FR) of hawthorn were obtained with maceration, using ethanol as an extraction solvent, and their antioxidant activity was evaluated. FL extract showed the highest FRS activity (EC50 3.72 ± 1.21 µg/ml), so it was selected to prepare microparticulate systems by a spray-drying technique, which were characterized by granulometric analysis, scanning electron microscopy-energy dispersive X-ray spectroscopy, confocal fluorescence microscopy and hyperoside content. Antioxidant activity was evaluated before and after gastrointestinal transit in vitro simulation. Results indicate that the microparticulate systems maintained the antioxidant activity of hawthorn also after gastrointestinal transit in vitro simulation, exhibiting properties suitable for oral administration.


Assuntos
Sequestradores de Radicais Livres/administração & dosagem , Extratos Vegetais/administração & dosagem , Administração Oral , Compostos de Bifenilo/química , Crataegus , Sistemas de Liberação de Medicamentos , Sequestradores de Radicais Livres/farmacologia , Microesferas , Picratos/química , Extratos Vegetais/farmacologia
14.
Int J Biol Macromol ; 270(Pt 2): 132493, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38763251

RESUMO

Ionotropic gelation is a low-cost, easy and green microencapsulation technique. However, the encapsulation of highly soluble compounds is challenging because of the wide loss of material into the external water phase by passive diffusion and the consequent low encapsulation efficiency. In this work an important increase of encapsulation efficiency for Thymus vulgaris L. aqueous extract in alginate-based microparticles has been obtained. A formulation with the proper thyme extract/alginate ratio (30:70) was used as reference and then optimized by adding different co-carrier excipients. Microparticles obtained by dropping a solution containing thyme extract and alginate into a chitosan/calcium-chloride/acid acetic solution lead to a high encapsulation efficiency (70.43 ± 5.28 %). After drying, microparticles had a particle size of 1096 ± 72 µm, 20.087 ± 1.487 % of extract content, 6.2 % of residual water, and showed a complete release of thyme extract within one hour. Combining alginate and chitosan as polymeric co-carrier was a valuable option for efficiently encapsulating an aqueous extract by ionotropic gelation.


Assuntos
Alginatos , Quitosana , Tamanho da Partícula , Extratos Vegetais , Thymus (Planta) , Quitosana/química , Alginatos/química , Thymus (Planta)/química , Extratos Vegetais/química , Microesferas , Água/química , Composição de Medicamentos/métodos , Portadores de Fármacos/química
15.
Pituitary ; 16(2): 238-44, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22915287

RESUMO

Germline mutations of aryl-hydrocarbon-receptor interacting protein (AIP) are associated with pituitary adenoma predisposition. They occur in 20 % of familial isolated pituitary adenoma (FIPA) and in about 3-5 % of sporadic pituitary adenomas, especially in early onset somatotropinomas and prolactinomas. Our aim was to evaluate the clinical and genetic features of a large Italian FIPA family, where an AIP variant was identified. AIP direct sequencing from genomic DNA was carried out in 16 available family members. AIP R16H carriers also underwent magnetic resonance imaging and hormonal assessments. AIP mutations were also searched in 16 patients with sporadic growth hormone-secreting pituitary adenoma and in 6 unrelated patients in whom pituitary adenoma was excluded. We found an AIP R16H variation in two family members harbouring a pituitary adenoma and in 6 unaffected family members. No AIP mutation was found neither in growth hormone-secreting pituitary adenoma patients, nor in the unrelated patients without pituitary adenoma. We report a FIPA family harbouring an AIP R16H change, supporting the hypothesis that the latter represents a variant of unknown significance.


Assuntos
Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Adulto , Feminino , Testes Genéticos , Humanos , Masculino , Mutação , Linhagem , Adulto Jovem
16.
J Mech Behav Biomed Mater ; 142: 105822, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37116309

RESUMO

Scaffolds for bone tissue engineering should be osteoinductive, osteoconductive, biocompatible, biodegradable, and, at the same time, exhibit proper mechanical properties. The present study investigated the mechanical properties of a coprinted hybrid scaffold made of polycaprolactone (PCL) and an alginate-based hydrogel, which was conceived to possess a double function of in vivo bio-integration (due to the ability of the hydrogel to release lyosecretome, a freeze-dried formulation of mesenchymal stem cell secretome with osteoinductive and osteoconductive properties) and withstanding loads (due to the presence of polycaprolactone, which provides mechanical resistance). To this end, an in-silico study was conducted to predict mechanical properties. Structural finite element analysis (FEA) of the hybrid scaffold under compression was performed to compare the numerical results with the corresponding experimental data. The impact of alginate inclusion and infill patterns on scaffold stiffness was investigated. Results show an increase in mechanical properties by changing the scaffold infill pattern (linear: 145.38±28.90 vs. honeycomb: 278.96±50.19, mean and standard deviation, n = 8), while alginate inclusion does not always impact the mechanical performance of the hybrid scaffold (stiffness: 145.38±28.90 vs. 195.42±38.68 N/mm, with vs without hydrogel inclusion, respectively). This is confirmed by FEA analysis, in which a good correspondence between experimental and numerical stiffness is shown (142±28.94 vs. 117.18, respectively, linear scaffold with hydrogel inclusion). In conclusion, the computational framework is a valid tool for predicting the mechanical performance of scaffolds and is promising for future clinical applications in the maxillofacial field.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Alicerces Teciduais/química , Análise de Elementos Finitos , Engenharia Tecidual/métodos , Poliésteres/química , Regeneração Óssea , Hidrogéis , Alginatos , Impressão Tridimensional
17.
Materials (Basel) ; 16(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37176269

RESUMO

The existence of more than thirty stress-strain equations, including those proposed by the government regulations in many countries, seems to indicate that additional, unifying, and at the same time generalizing research is necessary for this subject. Many expressions can be found to set or determine the initial modulus of elasticity of concrete, i.e., the modulus of elasticity of concrete when no load has been applied to it. This work proposes a complete generalization of the equations based on scalar damage models, applicable to all types of concrete tested under uniaxial compression with any constant rate of stress or strain, although in no case can it be considered a constitutive model. We prefer to discuss an equation that models the shape of the stress-strain curve. Thus, the shape of this curve is studied here in the same way a forensic scientist would, which is why we could see this work as an autopsy carried out on the test specimen through the trace left in the plane σ-ε by the straining process up until its inevitable outcome. That is to say, we believe in a purely phenomenological approach. The results are compared with the data obtained experimentally by analyzing test specimens made using various mixed portions of cement, water, and aggregates.

18.
Cancers (Basel) ; 15(6)2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36980611

RESUMO

Developing drug delivery systems to target cytotoxic drugs directly into tumor cells is still a compelling need with regard to reducing side effects and improving the efficacy of cancer chemotherapy. In this work, silk fibroin nanoparticles (SFNs) have been designed to load a previously described cytotoxic compound (NDI-1) that disrupts the cell cycle by specifically interacting with non-canonical secondary structures of DNA. SFNs were then functionalized on their surface with cyclic pentapeptides incorporating the Arg-Gly-Asp sequence (cRGDs) to provide active targeting toward glioma cell lines that abundantly express ανß3 and ανß5 integrin receptors. Cytotoxicity and selective targeting were assessed by in vitro tests on human glioma cell lines U373 (highly-expressing integrin subunits) and D384 cell lines (low-expressing integrin subunits in comparison to U373). SFNs were of nanometric size (d50 less than 100 nm), round shaped with a smooth surface, and with a negative surface charge; overall, these characteristics made them very likely to be taken up by cells. The active NDI-1 was loaded into SFNs with high encapsulation efficiency and was not released before the internalization and degradation by cells. Functionalization with cRGDs provided selectivity in cell uptake and thus cytotoxicity, with a significantly higher cytotoxic effect of NDI-1 delivered by cRGD-SFNs on U373 cells than on D384 cells. This manuscript provides an in vitro proof-of-concept of cRGD-silk fibroin nanoparticles' active site-specific targeting of tumors, paving the way for further in vivo efficacy tests.

19.
Pharmaceutics ; 15(2)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36839705

RESUMO

Sodium alginate (SA)-based hydrogels are often employed as bioink for three-dimensional (3D) scaffold bioprinting. They offer a suitable environment for cell proliferation and differentiation during tissue regeneration and also control the release of growth factors and mesenchymal stem cell secretome, which is useful for scaffold biointegration. However, such hydrogels show poor mechanical properties, fast-release kinetics, and low biological performance, hampering their successful clinical application. In this work, silk fibroin (SF), a protein with excellent biomechanical properties frequently used for controlled drug release, was blended with SA to obtain improved bioink and scaffold properties. Firstly, we produced a printable SA solution containing SF capable of the conformational change from Silk I (random coil) to Silk II (ß-sheet): this transition is a fundamental condition to improve the scaffold's mechanical properties. Then, the SA-SF blends' printability and shape fidelity were demonstrated, and mechanical characterization of the printed hydrogels was performed: SF significantly increased compressive elastic modulus, while no influence on tensile response was detected. Finally, the release profile of Lyosecretome-a freeze-dried formulation of MSC-secretome containing extracellular vesicles (EV)-from scaffolds was determined: SF not only dramatically slowed the EV release rate, but also modified the kinetics and mechanism release with respect to the baseline of SA hydrogel. Overall, these results lay the foundation for the development of SA-SF bioinks with modulable mechanical and EV-release properties, and their application in 3D scaffold printing.

20.
Bioact Mater ; 29: 16-35, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37456581

RESUMO

Neurodegenerative diseases represent a growing burden on healthcare systems worldwide. Mesenchymal stem cells (MSCs) have shown promise as a potential therapy due to their neuroregenerative, neuroprotective, and immunomodulatory properties, which are, however, linked to the bioactive substances they release, collectively known as secretome. This paper provides an overview of the most recent research on the safety and efficacy of MSC-derived secretome and extracellular vesicles (EVs) in clinical (if available) and preclinical models of Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, Huntington's disease, acute ischemic stroke, and spinal cord injury. The article explores the biologically active substances within MSC-secretome/EVs, the mechanisms responsible for the observed therapeutic effects, and the strategies that may be used to optimize MSC-secretome/EVs production based on specific therapeutic needs. The review concludes with a critical discussion of current clinical trials and a perspective on potential future directions in translating MSC-secretome and EVs into the clinic, specifically regarding how to address the challenges associated with their pharmaceutical manufacturing, including scalability, batch-to-batch consistency, adherence to Good Manufacturing Practices (GMP) guidelines, formulation, and storage, along with quality controls, access to the market and relative costs, value for money and impact on total expenditure.

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