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1.
Mol Cell Biochem ; 212(1-2): 45-50, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11108135

RESUMO

The anti-inflammatory cytokine IL-10 is up-regulated in response to TNF-alpha suggesting a control mechanism of inflammation. In addition, we recently found systemic IL-10 release in response to acute stress reactions in the absence of any systemic inflammation. In vitro and in vivo studies in experimental models suggest that catecholamines induce IL-10 release via a cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) dependent pathway. Here we studied patients for plasma IL-10 after acute myocardial infarction, a very stressful event without significant signs of systemic inflammation. In fact, the activation of the sympathetic system initiated by cardiac infarction was accompanied by a temporary systemic release of IL-10. Catecholamine induced IL-10 may be released by different cells. Recently, we demonstrated that catecholamines directly stimulate the IL-10 promoter/enhancer via a cAMP/PKA pathway in monocytic cells. A cAMP responsive element (CRE) was identified as major target. Here we show that there is no influence of catecholamines on the IL-10 promoter activity in T-cells. In contrast to monocytic cells, in T-cells cAMP-induced PKA-dependent phosphorylation of the CRE-binding protein 1 (CREB-1) seems to play a marginal role in IL-10 induction, which was reflected by a low cAMP-dependent IL-10-promoter/enhancer stimulation in reporter gene assays. Thus, catecholamines are directly involved in the regulation of IL-10 expression in monocytic but not in T-cells after acute stressful conditions.


Assuntos
Catecolaminas/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Interleucina-10/genética , Monócitos/imunologia , Infarto do Miocárdio/imunologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Ativação Transcricional , Doença Aguda , Idoso , Bucladesina/farmacologia , Catecolaminas/uso terapêutico , Linhagem Celular , Epinefrina/sangue , Feminino , Humanos , Interleucina-10/sangue , Células Jurkat , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Norepinefrina/sangue , Choque Cardiogênico/sangue , Choque Cardiogênico/tratamento farmacológico , Choque Cardiogênico/imunologia , Linfócitos T/imunologia , Transfecção
3.
J Biotechnol ; 76(1): 61-71, 2000 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-10784297

RESUMO

An electronic nose is used to monitor the bioreactor off-gas composition in perfused cultivations of a CHO-cell line producing recombinant human blood coagulation factor VIII. The applicability of the electronic nose for monitoring cellular state transitions and process control is explained. It is shown that the instrument can reveal characteristic process states related to product and lactate formation, and detect microbial infections in a very early stage of the infection. The visualization of ideal process conditions is realized by using principal component analysis (PCA) and the on-line applicability of this method is outlined. The results illustrate the potential of the electronic nose as on-line sensor for ensuring product and process quality in production-scale bioprocesses.


Assuntos
Técnicas Biossensoriais/métodos , Fator VIII/metabolismo , Animais , Reatores Biológicos , Células CHO , Cricetinae , Elétrons , Fator VIII/genética , Engenharia Genética/métodos , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
5.
Int J Mol Med ; 4(1): 61-5, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10373639

RESUMO

The p16INK4A (CDKN2A/MTS1) putative tumor suppressor gene encodes a cyclin dependent kinase inhibitor which plays an important role in the regulation of the G1/S phase cell cycle checkpoint. A high frequency of various p16 gene alterations were consequently observed in many primary tumors. P16 can be inactivated by different mechanisms: i) homozygous deletion, ii) methylation of the promoter region or iii) point mutation. In order to investigate p16 alterations in head and neck cancer (HNC) we analyzed 70 primary tumors of the larynx, pharynx and oral cavity including their corresponding normal mucosa for mutation inactivation by direct sequencing exon 2. We detected only one so far undescribed transversion G to T at position 322 (Asp108Tyr) and a known polymorphism (Ala148Thr) in five cases. The methylation status of the p16 promoter region was analyzed by an improved highly sensitive methylation-specific PCR protocol. P16 methylation inactivation was found in 16 of 55 cases (29%). Our data indicate that p16 point mutations in HNC are less frequent, but inactivation by methylation of the promoter region could be involved in genesis and progression of HNC.


Assuntos
Genes p16 , Neoplasias de Cabeça e Pescoço/genética , Mutação , Regiões Promotoras Genéticas , Sequência de Bases , Metilação de DNA , Análise Mutacional de DNA , Primers do DNA/genética , DNA de Neoplasias/química , DNA de Neoplasias/genética , Éxons , Humanos , Reação em Cadeia da Polimerase
6.
Ultraschall Med ; 15(6): 286-92, 1994 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-7846505

RESUMO

Absence of the septum pellucidum may occur as an isolated malformation. Some of the common paediatric ultrasound and radiology textbooks mention this anomaly. However, only 12 case reports have been published so far. Absent septum pellucidum is also seen in combination with other cerebral malformations like septo-optic pituitary dysplasia (SOPD, de Morsier), agenesis of corpus callosum, holoprosencephaly etc. More often it is seen as a secondary injury due to an increasing internal hydrocephalus. Occurrence of this aplasia and its significance are often underestimated. At a paediatric centre in Germany the anomaly is expected to occur in 1: 1,000 to 1:3,000 cerebral ultrasound examinations. After a review of the literature four cases are presented. All of them were observed by ultrasound during the neonatal period. Using ultrasonography diagnosis of the isolated absence of septum pellucidum can be easily performed by the experienced physician, and will usually be of eminent relevance for the patient.


Assuntos
Doenças em Gêmeos , Ecoencefalografia , Doenças do Prematuro/diagnóstico por imagem , Septo Pelúcido/anormalidades , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Doenças do Prematuro/patologia , Masculino , Exame Neurológico , Gravidez , Septo Pelúcido/diagnóstico por imagem , Septo Pelúcido/patologia
7.
J Biotechnol ; 34(3): 247-57, 1994 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-7764958

RESUMO

Based on experiments in bench scale, a recycling of spent cell culture medium was performed in a 100-1 pilot scale bioreactor. The cell cultivation has been done as a repeated batch procedure after the initial batch in the following four repeated batches spent medium from the previous batch was partially re-used. After microfiltration and ultrafiltration a part of the filtrate was mixed with a concentrate of amino acids and glucose, sterile filtered and subsequently filled back into the bioreactor. Up to 65% of the harvested cell- and product-free spent medium was re-used in each repeated batch. This procedure results in a saving of pure and waste water volume and saving of supplemented proteins as transferrin, insulin and lipoproteins and, therefore, also in a reduction of the production costs. A strongly acidic membrane ion exchanger was evaluated for the ability to purify the monoclonal antibodies from the pilot scale cultivation. Within minutes, gram quantities of product could be purified in a high flux system, especially developed for this purpose, achieving purities of 80%. The capacity of the acidic membrane ion exchanger was found in former investigations to be 1 mg cm-2 with recoveries up to 96%. Final purification was carried out by gel column filtration.


Assuntos
Cromatografia por Troca Iônica/métodos , Meios de Cultura , Técnicas Citológicas , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/isolamento & purificação , Biotecnologia/instrumentação , Contagem de Células , Divisão Celular , Cromatografia por Troca Iônica/instrumentação , Meios de Cultura/química , Meios de Cultura/isolamento & purificação , Técnicas Citológicas/instrumentação , Hibridomas/citologia , Hibridomas/imunologia , Membranas Artificiais , Camundongos , Projetos Piloto
8.
Cytotechnology ; 14(1): 1-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7765107

RESUMO

The production of small quantities of monoclonal antibodies and recombinant proteins was carried out using a new low cost production system, the Super Spinner. Into a 1 1 standard Duran flask a membrane stirrer equipped with a polypropylene hollow fiber membrane was installed to improve the oxygen supply by bubble-free aeration. The aeration was facilitated by using the CO2 conditioned incubator gas, which was pumped through the membrane stirrer via a small membrane pump. The maximal oxygen transfer rate (OTRmax) of the Super Spinner was detected. For this purpose one spinner flask was equipped with an oxygen electrode. The OTRmax was measured by the dynamic method. The ratio of membrane length to culture volume was adapted corresponding to the oxygen uptake rate of the cells according to the desired cell density. A balanced nutrient supply resulted in an optimal formation and yield of products.


Assuntos
Anticorpos Monoclonais/biossíntese , Dióxido de Carbono/metabolismo , Células Cultivadas , Oxigênio/metabolismo , Animais , Biotecnologia/economia , Biotecnologia/instrumentação , Biotecnologia/métodos , Células CHO , Custos e Análise de Custo , Cricetinae , Hibridomas/citologia , Proteínas Recombinantes/biossíntese
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