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1.
Clin Pharmacol Ther ; 114(5): 1043-1049, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37539657

RESUMO

The European Medicines Agency (EMA) offers guidance and support to pharmaceutical companies through bilateral discussions called business pipeline meetings (BPMs). An analysis of BPMs in oncology over a 5-year period was conducted to identify common topics and recurring queries. The documents of all BPMs available at the EMA regarding the field of oncology from January 1, 2018, to Decemer 31, 2022, were reviewed. For every query, a main category was assigned, and in case of multiple relevant topics, a secondary category was appointed too. For all queries, the follow-up offered by the EMA was documented, and whether the requested information was available. Subsequently, all queries were scanned for overlapping topics between meetings. From 2018 to 2022, 31 BPMs were held between the EMA and pharmaceutical companies to discuss oncology-related questions, for a total of 397 queries raised. They were classified into 24 topics, of which 15 were common topics (n ≥ 10 queries) with regulatory pathways/guidelines and trial design having the most queries. Post-BPM actions were taken or recommended by the EMA for 41.3% of queries, such as referrals to scientific advice or published guidelines. Forty-three queries were raised at more than one BPM. Targeted therapy, companion diagnostics, institutional collaboration, trial design, and regulatory pathways/guidelines were the most discussed topics in oncology BPMs, with molecular developments being the common denominator. Creating Q&A documents, publishing new guidelines, providing a framework for discussions, and questionnaire-based follow-up research can improve the quality of BPMs, and the accessibility of the information requested during the BPMs.

2.
Eur J Neurosci ; 47(12): 1474-1481, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29904972

RESUMO

Evoked electrical muscle activity suppresses the transcription of mRNAs for acetylcholine receptors in extrajunctional myonuclei. Muscle denervation or disuse releases such inhibition and extrajunctional receptors appear. However, in soleus muscles paralysed with nerve-applied tetrodotoxin, a restricted perijunctional region has been described where myonuclei remain inhibited, a finding attributed to nerve-derived trophic factor(s). Here, we reinvestigate extrajunctional acetylcholine receptor expression in soleus and extensor digitorum longus muscles up to 90 days after denervation or up to 20 days of disuse, to clarify the role of trophic factors, if any. The perijunctional region of soleus muscles strongly expressed acetylcholine receptors during the first 2-3 weeks of denervation. After 2-3 months, this expression had disappeared. No perijunctional expression was seen after paralysis by tetrodotoxin or botulinum toxin A. In contrast, the extensor digitorum longus never displayed suppressed perijunctional acetylcholine receptor expression after any treatment, suggesting that it is an intrinsic property of soleus muscles. Soleus denervation only transiently removed the suppression, and its presence in long-term denervated soleus muscles contradicts any contribution from nerve-derived trophic factor(s). In conclusion, our results confirm that evoked electrical activity is the physiological factor controlling the expression of acetylcholine receptors in the entire extrajunctional membrane of skeletal muscles.


Assuntos
Fenômenos Eletrofisiológicos/fisiologia , Atividade Motora/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Fatores de Crescimento Neural/metabolismo , Receptores Colinérgicos/metabolismo , Inibidores da Liberação da Acetilcolina/farmacologia , Animais , Autorradiografia , Masculino , Denervação Muscular , Ratos , Ratos Wistar , Bloqueadores dos Canais de Sódio/farmacologia
3.
Expert Rev Clin Pharmacol ; 8(3): 353-60, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25797498

RESUMO

Unmet medical needs are a priority for organizations such as the WHO and major public-private initiatives, such as Innovative Medicines Initiative, were established to speed up the development of better and safer medicines for patients. To assist such projects, the EMA in its 'Road Map to 2015' considered the mapping of unmet medical needs as a priority. This study has identified medical conditions for which the EMA could not identify developments in the pharmaceutical pipelines, that is, 'white spots'. Our analysis was made using external data sources as well as mining data of the EMA. The main areas for white spots were oncology, infectious diseases and certain psychiatric conditions. According to our data and a review of literature, in a number of these white spots, diagnostic tools may even be missing. The identification of those conditions will benefit stakeholders, including regulators, research funding bodies and patients' organizations.


Assuntos
Desenho de Fármacos , Indústria Farmacêutica , Necessidades e Demandas de Serviços de Saúde , Animais , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/tratamento farmacológico , União Europeia , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/tratamento farmacológico , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Parcerias Público-Privadas
4.
Tissue Eng Part A ; 14(6): 1067-80, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18500918

RESUMO

OBJECTIVE: The aim of the study was to investigate the use of a novel hyaluronic acid/polycaprolactone material for meniscal tissue engineering and to evaluate the tissue regeneration after the augmentation of the implant with expanded autologous chondrocytes. Two different surgical implantation techniques in a sheep model were evaluated. METHODS: Twenty-four skeletally mature sheep were treated with total medial meniscus replacements, while two meniscectomies served as empty controls. The animals were divided into two groups: cell-free scaffold and scaffold seeded with autologous chondrocytes. Two different surgical techniques were compared: in 12 animals, the implant was sutured to the capsule and to the meniscal ligament; in the other 12 animals, also a transtibial fixation of the horns was used. The animals were euthanized after 4 months. The specimens were assessed by gross inspection and histology. RESULTS: All implants showed excellent capsular ingrowth at the periphery. Macroscopically, no difference was observed between cell-seeded and cell-free groups. Better implant appearance and integrity was observed in the group without transosseous horns fixation. Using the latter implantation technique, lower joint degeneration was observed in the cell-seeded group with respect to cell-free implants. The histological analysis indicated cellular infiltration and vascularization throughout the implanted constructs. Cartilaginous tissue formation was significantly more frequent in the cell-seeded constructs. CONCLUSION: The current study supports the potential of a novel HYAFF/polycaprolactone scaffold for total meniscal substitution. Seeding of the scaffolds with autologous chondrocytes provides some benefit in the extent of fibrocartilaginous tissue repair.


Assuntos
Meniscos Tibiais/fisiologia , Meniscos Tibiais/cirurgia , Modelos Animais , Ovinos , Engenharia Tecidual/métodos , Animais , Cartilagem Articular/citologia , Cartilagem Articular/transplante , Condrócitos/transplante , Feminino , Implantes Experimentais , Articulações/patologia , Microscopia Eletrônica de Varredura , Porosidade , Alicerces Teciduais
5.
Cells Tissues Organs ; 186(2): 97-103, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17489021

RESUMO

Articular cartilage injuries have poor reparative capability and, if left untreated, may progress to osteo-arthritis. Unsatisfactory results with conventional treatment methods have prompted the development of innovative solutions including the use of cell transplantations, with or without a supporting scaffold. Tissue engineering combines cells, scaffolds and bio-active factors, which represents one of the most promising approaches for the restoration of damaged tissues. Available today, hyaluronan, also known as hyaluronic acid, is a natural glycosaminoglycan present in all soft tissues of higher organisms and in particularly high concentrations in the extracellular matrix of articular cartilage and in the mesenchyme during embryonic development in which it plays a number of biological functions, not only as a structural component but as an informational molecule as well. Moreover, hyaluronan can be manufactured in a variety of physical forms including hydrogels, sponges, fibres and fabrics allowing to develop a variety of hyaluronan-based scaffolds. This review will present both theoretical and experimental evidences that led to the development of Hyalograft C, an exploitation of hyaluronic acid technology and a tissue engineering approach for the resolution of articular cartilage defects.


Assuntos
Materiais Biocompatíveis , Cartilagem Articular/lesões , Ácido Hialurônico , Engenharia Tecidual , Cartilagem Articular/cirurgia , Condrócitos/transplante , Humanos
6.
Tissue Eng ; 12(7): 1851-63, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16889515

RESUMO

These studies address critical technical issues involved in creating human mesenchymal stem cell (hMSC)/ scaffold implants for cartilage repair. These issues include obtaining a high cell density and uniform spatial cell distribution within the scaffold, factors that are critical in the initiation and homogeneity of chondrogenic differentiation. For any given scaffold, the initial seeding influences cell density, retention, and spatial distribution within the scaffold, which eventually will affect the function of the construct. Here, we discuss the development of a vacuum-aided seeding technique for HYAFF -11 sponges which we compared to passive infiltration. Our results show that, under the conditions tested, hMSCs were quantitatively and homogeneously loaded into the scaffolds with 90+% retention rates after 24 h in perfusion culture with no negative effect on cell viability or chondrogenic potential. The retention rates of the vacuum-seeded constructs were at least 2 times greater than those of passively seeded constructs at 72 h. Histomorphometric analysis revealed that the core of the vacuum-seeded constructs contained 240% more cells than the core of passively infiltrated scaffolds. The vacuum seeding technique is safe, rapid, reproducible, and results in controlled quantitative cell loading, high retention, and uniform distribution.


Assuntos
Materiais Biocompatíveis , Cartilagem , Técnicas de Cultura de Células , Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Reatores Biológicos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Sobrevivência Celular , Condrócitos/citologia , Condrócitos/fisiologia , Humanos , Células-Tronco Mesenquimais/fisiologia , Engenharia Tecidual
7.
Tissue Eng ; 11(7-8): 1122-32, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16144448

RESUMO

Hybrid cardiac constructs with mechanical properties suitable for in vitro loading studies and in vivo implantation were constructed from neonatal rat heart cells, fibrin (Fn), and biodegradable knitted fabric (Knit). Initial (2-h) constructs were compared with native heart tissue, studied in vitro with respect to mechanical function (stiffness, ultimate tensile strength [UTS], failure strain epsilon(f), strain energy density E) and compositional remodeling (collagen, DNA), and implanted in vivo. For 2-h constructs, stiffness was determined mainly by the Fn and was half as high as that of native heart, whereas UTS, epsilon(f), and E were determined by the Knit and were, respectively, 8-, 7-, and 30-fold higher than native heart. Over 1 week of static in vitro culture, cell-mediated, serum-dependent remodeling was demonstrated by a 5-fold increase in construct collagen content and maintenance of stiffness not observed in cell-free constructs. Cyclic stretch further increased construct collagen content in a manner dependent on loading regimen. The presence of cardiac cells in cultured constructs was demonstrated by immunohistochemistry (troponin I) and Western blot (connexin 43). However, in vitro culture reduced Knit mechanical properties, decreasing UTS, epsilon(f), and E of both constructs and cell-free constructs and motivating in vivo study of the 2-h constructs. Constructs implanted subcutaneously in nude rats for 3 weeks exhibited the continued presence of cardiomyocytes and blood vessel ingrowth by immunostaining for troponin I, connexin 43, and CD-31. Together, the data showed that hybrid cardiac constructs initially exhibited supraphysiologic UTS, epsilon(f), and E, and remodeled in response to serum and stretch in vitro and in an ectopic in vivo model.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis/química , Elastômeros/química , Fibrina/química , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Engenharia Tecidual/métodos , Animais , Animais Recém-Nascidos , Materiais Biocompatíveis/análise , Bioprótese , Técnicas de Cultura de Células/métodos , Proliferação de Células , Sobrevivência Celular/fisiologia , Células Cultivadas , Elasticidade , Elastômeros/análise , Teste de Materiais , Neovascularização Fisiológica/fisiologia , Ratos , Ratos Sprague-Dawley , Resistência à Tração/fisiologia , Têxteis , Remodelação Ventricular/fisiologia
8.
Osteoarthritis Cartilage ; 13(10): 896-905, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16019238

RESUMO

OBJECTIVE: Development and remodeling of engineered cartilage-explant composites were studied in vitro and in vivo. DESIGN: Individual and interactive effects of cell chondrogenic potential (primary or fifth passage bovine calf chondrocytes), scaffold degradation rate (hyaluronan benzyl ester or polyglycolic acid), and adjacent tissue cell activity and architecture (vital trabecular bone (VB), articular cartilage (AC), devitalized bone (DB) or digested cartilage (DC)) were evaluated over 8 weeks in vitro (bioreactor cultures) and in vivo (ectopic implants). RESULTS: In vitro, significant effects of cell type on construct adhesive strength (P<0.001) and scaffold type on adhesive strength (P<0.001), modulus (P=0.014), glycosaminoglycans (GAG) (P<0.001), and collagen (P=0.039) were observed. Chondrogenesis was best when the scaffold degradation rate matched the extracellular matrix deposition rate. In vivo, adjacent tissue type affected adhesive strength (P<0.001), modulus (P<0.001), and GAG (P<0.001) such that 8-week values obtained for bone (VB and DB) were higher than for cartilage (AC). In the AC/construct group, chondrogenesis appeared attenuated in the region of the construct close to the AC. In contrast, in the VB/construct group, a 500 microm thick zone of mature hyaline-like cartilage formed at the interface, and signs of active remodeling were present in the bone that included osteoclastic and osteoblastic activity and trabecular rebuttressing; these features were not present in the DB group or in vitro. CONCLUSIONS: Development and remodeling of composites based on engineered cartilage were mediated in vitro by cell chondrogenic potential and scaffold degradation rate, and in vivo by type of adjacent tissue and time.


Assuntos
Remodelação Óssea/fisiologia , Cartilagem Articular/transplante , Condrócitos/transplante , Engenharia Tecidual/métodos , Animais , Fenômenos Biomecânicos , Reatores Biológicos , Cartilagem Articular/citologia , Cartilagem Articular/fisiologia , Bovinos , Adesão Celular/fisiologia , Células Cultivadas , Condrócitos/citologia , Condrogênese/fisiologia
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