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1.
Biotechnol Bioeng ; 112(1): 1-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25060508

RESUMO

Plant cell and tissue cultivations are of growing interest for the production of structurally complex and expensive plant-derived products, especially in pharmaceutical production. Problems with up-scaling, low yields, and high-priced process conditions result in an increased demand for models to provide comprehension, simulation, and optimization of production processes. In the last 25 years, many models have evolved in plant biotechnology; the majority of them are specialized models for a few selected products or nutritional conditions. In this article we review, delineate, and discuss the concepts and characteristics of the most commonly used models. Therefore, the authors focus on models for plant suspension and submerged hairy root cultures. The article includes a short overview of modeling and mathematics and integrated parameters, as well as the application scope for each model. The review is meant to help researchers better understand and utilize the numerous models published for plant cultures, and to select the most suitable model for their purposes.


Assuntos
Biotecnologia/métodos , Células Vegetais , Plantas , Técnicas de Cultura de Tecidos/métodos , Cinética , Modelos Biológicos , Plantas/embriologia , Plantas/metabolismo
2.
Appl Microbiol Biotechnol ; 98(5): 2029-40, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24318010

RESUMO

Tocopherols, collectively known as vitamin E, are lipophilic antioxidants, which are synthesized only by photosynthetic organisms. Due to their enormous potential to protect cells from oxidative damage, tocopherols are used, e.g., as nutraceuticals and additives in pharmaceuticals. The most biologically active form of vitamin E is α-tocopherol. Most tocopherols are currently produced via chemical synthesis. Nevertheless, this always results in a racemic mixture of different and less effective stereoisomers because the natural isomer has the highest biological activity. Therefore, tocopherols synthesized in natural sources are preferred for medical purposes. The annual sunflower (Helianthus annuus L.) is a well-known source for α-tocopherol. Within the presented work, sunflower callus and suspension cultures were established growing under photomixotrophic conditions to enhance α-tocopherol yield. The most efficient callus induction was achieved with sunflower stems cultivated on solid Murashige and Skoog medium supplemented with 30 g l(-1) sucrose, 0.5 mg l(-1) of the auxin 1-naphthalene acetic acid, and 0.5 mg l(-1) of the cytokinin 6-benzylaminopurine. Photomixotrophic sunflower suspension cultures were induced by transferring previously established callus into liquid medium. The effects of light intensity, sugar concentration, and culture age on growth rate and α-tocopherol synthesis rate were characterized. A considerable increase (max. 230%) of α-tocopherol production in the cells was obtained within the photomixotrophic cell culture compared to a heterotrophic cell culture. These results will be useful for improving α-tocopherol yields of plant in vitro cultures.


Assuntos
Biotecnologia/métodos , Helianthus/crescimento & desenvolvimento , Helianthus/metabolismo , alfa-Tocoferol/metabolismo , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Glucose/metabolismo , Luz
3.
Pharmacol Res Perspect ; 12(1): e1166, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38204399

RESUMO

A better understanding of patients' adherence to treatment is a prerequisite to maximize the benefit of healthcare provision for patients, reduce treatment costs, and is a key factor in a variety of subsequent health outcomes. We aim to understand the state of the art of scientific evidence about which factors influence patients' adherence to treatment. A systematic literature review was conducted using PRISMA guidelines in five separate electronic databases of scientific publications: PubMed, PsycINFO (ProQuest), Cochrane library (Ovid), Google Scholar, and Web of Science. The search focused on literature reporting the significance of factors in adherence to treatment between 2011 and 2021, including only experimental studies (e.g., randomized controlled trials [RCT], clinical trials, etc.). We included 47 experimental studies. The results of the systematic review (SR) are grouped according to predetermined categories of the World Health Organization (WHO): socioeconomic, treatment, condition, personal, and healthcare-related factors. This review gives an actual overview of evidence-based studies on adherence and analyzed the significance of factors defined by the WHO classification. By showing the strength of certain factors in several independent studies and concomitantly uncovering gaps in research, these insights could serve as a basis for the design of future adherence studies and models.


Assuntos
Custos de Cuidados de Saúde , Cooperação do Paciente , Humanos , Bases de Dados Factuais , Organização Mundial da Saúde
4.
Bioprocess Biosyst Eng ; 34(3): 287-95, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20872271

RESUMO

Modelling of activated sludge processes is a commonly used technique to design and optimize wastewater treatment processes. Since wastewater and activated sludge is characterized by chemical oxygen demand (COD) measurements, units of state variables describing organic matter are expressed as equivalent amounts of COD. However, current procedures for measuring it have several drawbacks, including the production of hazardous wastes, so the utility of other variables for characterizing the organic load in modelling, such as total organic carbon (TOC), warrant re-evaluation. Other advantages of TOC over COD are that it provides matrix-independent analytical results and it can be readily measured online. Proposals for TOC-based models were made in the 1990s, but they seem to have sunk into obscurity. To re-assess the value of TOC for this purpose, we have recalculated the EAWAG module for Bio-P removal coupled to the Activated Sludge Model No. 3 on a TOC basis, and tested it against data acquired in batch experiments with four single carbon sources (acetate, glucose, citrate and casein). The batch test-based calibrations showed a good match with experimental data, following modifications of the model to account for the anaerobic volumes and retention times applied in the tests.


Assuntos
Reatores Biológicos/microbiologia , Reatores Biológicos/normas , Carbono/química , Modelos Biológicos , Fósforo/análise , Esgotos/química , Acetatos/química , Acetatos/metabolismo , Bactérias Aeróbias/metabolismo , Bactérias Anaeróbias/metabolismo , Análise da Demanda Biológica de Oxigênio/normas , Biomassa , Calibragem , Carbono/metabolismo , Caseínas/química , Caseínas/metabolismo , Ácido Cítrico/química , Ácido Cítrico/metabolismo , Glucose/química , Glucose/metabolismo , Fósforo/química , Eliminação de Resíduos Líquidos/métodos
5.
Oral Oncol ; 116: 105259, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33895463

RESUMO

Immune checkpoint blockade can cause regression of recurrent and/or refractory head and neck squamous cell carcinoma (HNSCC). As a second type of immunotherapy, adoptive cellular therapy with genetically modified patient's T-cells redirected against the autologous malignant cells by expressing chimeric antigen receptors (CARs) recognizing tumor-associated antigens has been established as highly efficient personalized treatment for hematological malignancies. In solid cancers however, the application of these genetically modified immune effector cells still lacks equal response rates. CD44v6 is an isoform of the hyaluronic receptor CD44 that is almost exclusively expressed at high levels on solid cancers and has been associated with tumorigenesis, tumor cell invasion and metastasis. Here, we established a highly specific CAR against CD44v6 on HNSCC cells that can be expressed on normal T-cells with lentiviral vectors. Using primary human HNSCC cells in combination with CRISPR/Cas9 and overexpression approaches allowed us to confirm the high specificity of our CAR construct for the tumor-associated CD44v6 as target antigen and to demonstrate a direct correlation between CD44v6 expression levels and cytotoxicity of the CAR T-cells. Importantly, the design of our clinically applicable lentiviral vector facilitates to co-express a second transgene for in vivo control of CAR T-cells, if undesired side-effects or toxicities occur.


Assuntos
Neoplasias de Cabeça e Pescoço , Receptores de Hialuronatos/imunologia , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Receptores de Hialuronatos/genética , Recidiva Local de Neoplasia , Isoformas de Proteínas , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Linfócitos T/imunologia , Linfócitos T/transplante
6.
Neuropsychologia ; 46(5): 1505-12, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18294661

RESUMO

There are several reports on the ability aphasic patients have to sing familiar songs, despite having severe speech impairments. Based on these observations it was also suggested that singing might improve speech production. However, recent experimental studies with aphasic patients found no evidence to illustrate that singing improves word production under controlled experimental conditions. This study investigated the role of singing during repetition of word phrases in a patient severely affected with non-fluent aphasia (GS) who had an almost complete lesion of the left hemisphere. GS showed a pronounced increase in the number of correctly reproduced words during singing as compared to speaking excerpts of familiar lyrics. This dissociation between singing and speaking was not seen for novel song lyrics, regardless of whether these were coupled with an unfamiliar, a familiar, or a spontaneously generated melody during the singing conditions. These findings propose that singing might help word phrase production in at least some cases of severe expressive aphasia. However, the association of melody and text in long-term memory seems to be responsible for this effect.


Assuntos
Afasia/psicologia , Música/psicologia , Fala/fisiologia , Afasia/etiologia , Atenção/fisiologia , Humanos , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/psicologia
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