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1.
Strahlenther Onkol ; 195(11): 982-990, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31346674

RESUMO

PURPOSE: In this pilot trial, we investigate the safety of CT-guided high-dose-rate brachytherapy (HDR-BT) as a local ablative treatment for renal masses not eligible for resection or nephrectomy. METHODS: We investigated renal function after irradiation by HDR-BT in 16 patients (11 male, 5 female, mean age 76 years) with 20 renal lesions (renal cell carcinoma n = 18; renal metastases n = 2). Two patients had previous contralateral nephrectomy and two had ipsilateral partial nephrectomy. Six lesions had a hilar localization with proximity to the renal pelvis and would have not been favorable for thermal ablation. Renal function loss was determined within 1 year after HDR-BT by renal scintigraphy and laboratory parameters. Further investigations included CT and MRI every 3 months to observe procedural safety and local tumor control. Renal function tests were analyzed by Wilcoxon's signed rank test with Bonferroni-Holm correction of p-values. Survival and local tumor control underwent a Kaplan-Meier estimation. RESULTS: Median follow-up was 22.5 months. One patient required permanent hemodialysis 32 months after repeated HDR-BT and contralateral radiofrequency ablation of multifocal renal cell carcinoma. No other patient developed a significant worsening in global renal function and no gastrointestinal or urogenital side effects were observed. Only one patient died of renal tumor progression. Local control rate was 95% including repeated HDR-BT of two recurrences. CONCLUSION: HDR-BT is a feasible and safe technique for the local ablation of renal masses. A phase II study is recruiting to evaluate the efficacy of this novel local ablative treatment in a larger study population.


Assuntos
Braquiterapia/métodos , Carcinoma de Células Renais/radioterapia , Neoplasias Renais/radioterapia , Ablação por Radiofrequência/métodos , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Rim/efeitos da radiação , Testes de Função Renal , Neoplasias Renais/secundário , Masculino , Segurança do Paciente , Projetos Piloto , Lesões por Radiação/etiologia
2.
BMC Cancer ; 19(1): 173, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808323

RESUMO

BACKGROUND: The aim of this analysis was to model the effect of local control (LC) on overall survival (OS) in patients treated with stereotactic body radiotherapy (SBRT) for liver or lung metastases from colorectal cancer. METHODS: The analysis is based on pooled data from two retrospective SBRT databases for pulmonary and hepatic metastases from 27 centers from Germany and Switzerland. Only patients with metastases from colorectal cancer were considered to avoid histology as a confounding factor. An illness-death model was employed to model the relationship between LC and OS. RESULTS: Three hundred eighty-eight patients with 500 metastatic lesions (lung n = 209, liver n = 291) were included and analyzed. Median follow-up time for local recurrence assessment was 12.1 months. Ninety-nine patients with 112 lesions experienced local failure. Seventy-one of these patients died after local failure. Median survival time was 27.9 months in all patients and 25.4 months versus 30.6 months in patients with and without local failure after SBRT. The baseline risk of death after local failure exceeds the baseline risk of death without local failure at 10 months indicating better survival with LC. CONCLUSION: In CRC patients with lung or liver metastases, our findings suggest improved long-term OS by achieving metastatic disease control using SBRT in patients with a projected OS estimate of > 12 months.


Assuntos
Neoplasias Colorretais/radioterapia , Neoplasias Hepáticas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/secundário , Bases de Dados Factuais , Feminino , Seguimentos , Alemanha , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Análise de Sobrevida , Suíça , Resultado do Tratamento , Adulto Jovem
3.
Radiologe ; 58(8): 730-735, 2018 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-29947930

RESUMO

BACKGROUND: The clinical target volume (CTV) is regarded fundamental for radiotherapy planning by the International Commission on Radiation Units and Measurements (ICRU). OBJECTIVES: The aim of this article is to give an overview on the basics and problems of defining the CTV for radiotherapy planning. MATERIALS AND METHODS: After briefly defining CTV, a short description of the process to homogenize CTV in intraindividual comparisons is given, where special attention is paid to radiological requirements. This information is summarized in a number of tables. RESULTS: CTV is the most complex volume among the target volumes that have been defined by the ICRU. A survey of the determinants of the definition of CTV is given. CONCLUSIONS: This overview on the basic rules of how to define CTVs can help to increase the understanding of the radiological requirements for optimum imaging to support radiotherapy planning regardless of the specialty of the physician.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X
4.
Strahlenther Onkol ; 193(8): 612-619, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28341865

RESUMO

PURPOSE: To assess the efficacy, safety, and outcome of image-guided high-dose-rate (HDR) brachytherapy in patients with adrenal gland metastases (AGM). MATERIALS AND METHODS: From January 2007 to April 2014, 37 patients (7 female, 30 male; mean age 66.8 years, range 41.5-82.5 years) with AGM from different primary tumors were treated with CT-guided HDR interstitial brachytherapy (iBT). Primary endpoint was local tumor control (LTC). Secondary endpoints were time to untreatable progression (TTUP), time to progression (TTP), overall survival (OS), and safety. In a secondary analysis, risk factors with an influence on survival were identified. RESULTS: The median biological equivalent dose (BED) was 37.4 Gy. Mean LTC after 12 months was 88%; after 24 months this was 74%. According to CTCAE criteria, one grade 3 adverse event occurred. Median OS after first diagnosis of AGM was 18.3 months. Median OS, TTUP, and TTP after iBT treatment were 11.4, 6.6, and 3.5 months, respectively. Uni- and multivariate Cox regression analyses revealed significant influences of synchronous disease, tumor diameter, and the total number of lesions on OS or TTUP or both. CONCLUSION: Image-guided HDR-iBT is safe and effective. Treatment- and primary tumor-independent features influenced survival of patients with AGM after HDR-iBR treatment.


Assuntos
Neoplasias das Glândulas Suprarrenais/radioterapia , Braquiterapia/mortalidade , Carcinoma/prevenção & controle , Carcinoma/secundário , Fracionamento da Dose de Radiação , Recidiva Local de Neoplasia/mortalidade , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/mortalidade , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Prevalência , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
5.
Radiologe ; 52(1): 70-3, 2012 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-22249704

RESUMO

CLINICAL/METHODICAL ISSUE: Minimally invasive treatment procedures, such as image-guided local tumour ablation have gained increasing relevance in oncologic concepts. Limitations of thermal ablation procedures have led to the development of percutaneous, computed tomography (CT) guided brachytherapy. STANDARD RADIOLOGICAL METHODS: Thermal ablation procedures, such as radiofrequency ablation (RFA) and laser-induced thermotherapy (LITT) show limitations regarding maximum tumour size (<5 cm), cooling effects of adjacent vessels and surrounding risk structures. METHODICAL INNOVATIONS: The image-guided interstitial brachytherapy allows the single application of high-dose rate (HDR) irradiation with an extensive protracted cytotoxic effect. Adjacent risk structures play a minor role due to the steep dose gradient outside the clinical target volume. PERFORMANCE: Studies using CT-guided brachytherapy resulted in a local tumour control rate of approximately 90% after 12 months in the treatment of hepatocellular carcinoma (HCC) and 70-90% in the treatment of colorectal metastases or cholangiocellular carcinoma (CCC). Similar response rates were also seen in the treatment of metastases of renal cell carcinoma (RCC), non-small cell lung cancer (NSCLC) or neuroendocrine tumours. In colorectal liver metastases and HCC the method has proven to have a positive impact on prognosis. ACHIEVEMENTS: In contrast to thermal ablation the method can be used without restriction with respect to tumour location. Cooling effects do not play a role. It has already been applied in more than 5,000 cases and it is used in clinical routine. PRACTICAL RECOMMENDATIONS: Image-guided brachytherapy is safe and effective and has found its way into the clinical routine.


Assuntos
Braquiterapia/tendências , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Radioterapia Guiada por Imagem/tendências , Tomografia Computadorizada por Raios X/tendências , Humanos
6.
Science ; 230(4728): 943-5, 1985 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-3933111

RESUMO

Modulation of the growth of human and murine cell lines in vitro by recombinant human tumor necrosis factor-alpha (rTNF-alpha) and recombinant human interferon-gamma (rIFN-gamma) was investigated. rTNF-alpha had cytostatic or cytolytic effects on only some tumor cell lines. When administered together with rIFN-gamma, rTNF-alpha showed enhanced antiproliferative effects on a subset of the cell lines tested. In contrast to its effects on sensitive tumor cells, rTNF-alpha augmented the growth of normal diploid fibroblasts. Variations in the proliferative response induced by rTNF-alpha were apparently not due to differences in either the number of binding sites per cell or their affinity for rTNF-alpha. These observations indicate that the effects of rTNF-alpha on cell growth are not limited to tumor cells, but rather that this protein may have a broad spectrum of activities in vivo.


Assuntos
Divisão Celular/efeitos dos fármacos , Glicoproteínas/farmacologia , Proteínas Recombinantes/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/patologia , Sinergismo Farmacológico , Humanos , Interferon gama/farmacologia , Camundongos , Fator de Necrose Tumoral alfa
7.
Science ; 246(4937): 1601-3, 1989 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-2688092

RESUMO

Certain inflammatory stimuli render cultured human vascular endothelial cells hyperadhesive for neutrophils. This state is transient and reversible, in part because activated endothelial cells secrete a leukocyte adhesion inhibitor (LAI). LAI was identified as endothelial interleukin-8 (IL-8), the predominant species of which is an extended amino-terminal IL-8 variant. At nanomolar concentrations, purified endothelial IL-8 and recombinant human IL-8 inhibit neutrophil adhesion to cytokine-activated endothelial monolayers and protect these monolayers from neutrophil-mediated damage. These findings suggest that endothelial-derived IL-8 may function to attenuate inflammatory events at the interface between vessel wall and blood.


Assuntos
Fatores Quimiotáticos/isolamento & purificação , Endotélio Vascular/fisiologia , Interleucina-1/farmacologia , Interleucinas/isolamento & purificação , Neutrófilos/fisiologia , Sequência de Aminoácidos , Fatores Biológicos/farmacologia , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Fatores Quimiotáticos/farmacologia , Meios de Cultura/análise , Citocinas , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Humanos , Interleucina-8 , Interleucinas/farmacologia , Dados de Sequência Molecular , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Proteínas Recombinantes/farmacologia
8.
Radiother Oncol ; 127(2): 246-252, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29510865

RESUMO

BACKGROUND: Stereotactic body radiotherapy (SBRT) for oligometastatic disease is characterized by an excellent safety profile; however, experiences are mostly based on treatment of one single metastasis. It was the aim of this study to evaluate safety and efficacy of SBRT for multiple pulmonary metastases. PATIENTS AND METHODS: This study is based on a retrospective database of the DEGRO stereotactic working group, consisting of 637 patients with 858 treatments. Cox regression and logistic regression were used to analyze the association between the number of SBRT treatments or the number and the timing of repeat SBRT courses with overall survival (OS) and the risk of early death. RESULTS: Out of 637 patients, 145 patients were treated for multiple pulmonary metastases; 88 patients received all SBRT treatments within one month whereas 57 patients were treated with repeat SBRT separated by at least one month. Median OS for the total patient population was 23.5 months and OS was not significantly influenced by the overall number of SBRT treatments or the number and timing of repeat SBRT courses. The risk of early death within 3 and 6 months was not increased in patients treated with multiple SBRT treatments, and no grade 4 or grade 5 toxicity was observed in these patients. CONCLUSIONS: In appropriately selected patients, synchronous SBRT for multiple pulmonary oligometastases and repeat SBRT may have a comparable safety and efficacy profile compared to SBRT for one single oligometastasis.


Assuntos
Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Radiocirurgia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Radiother Oncol ; 123(2): 182-188, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28169042

RESUMO

BACKGROUND: Radical local treatment of pulmonary metastases is practiced with increasing frequency due to acknowledgment and better understanding of oligo-metastatic disease. This study aimed to develop a nomogram predicting overall survival (OS) after stereotactic body radiotherapy (SBRT) for pulmonary metastases. PATIENTS AND METHODS: A multi-institutional database of 670 patients treated with SBRT for pulmonary metastases was used as training cohort. Cox regression analysis with bidirectional variable elimination was performed to identify factors to be included into the nomogram model to predict 2-year OS. The calibration rate of the nomogram was assessed by plotting the actual Kaplan-Meier 2-year OS against the nomogram predicted survival. The nomogram was externally validated using two separate monocentric databases of 145 and 92 patients treated with SBRT for pulmonary metastases. RESULTS: The median follow up of the trainings cohort was 14.3months, the 2-year and 5-year OS was 52.6% and 23.7%, respectively. Karnofsky performance index, type of the primary tumor, control of the primary tumor, maximum diameter of the largest treated metastasis and number of metastases (1 versus >1) were significant prognostic factors in the Cox model (all p<0.05). The calculated concordance-index for the nomogram was 0.73 (concordance indexes of all prognostic factors between 0.54 and 0.6). Based on the nomogram the training cohort was divided into 4 groups and 2-year OS ranged between 24.2% and 76.1% (predicted OS between 30.2% and 78.4%). The nomogram discriminated between risk groups in the two validation cohorts (concordance index 0.68 and 0.67). CONCLUSIONS: A nomogram for prediction of OS after SBRT for pulmonary metastases was generated and externally validated. This tool might be helpful for interdisciplinary discussion and evaluation of local and systemic treatment options in the oligo-metastatic setting. KEY MESSAGE: A nomogram for prediction of overall survival after stereotactic body radiotherapy (SBRT) for pulmonary metastases was developed and externally validated. This tool might be helpful for interdisciplinary discussion and evaluation of local and systemic treatment options in the oligo-metastatic setting.


Assuntos
Neoplasias Pulmonares/radioterapia , Nomogramas , Radiocirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Acta Biomater ; 11: 256-63, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25242649

RESUMO

The hierarchical structure of wood is composed of a cellulose skeleton of high structural order at various length scales. At the nanoscale and microscale the specific structural features of the cells and cell walls result in a lightweight structure with an anisotropic material profile of excellent mechanical performance. By being able to specifically functionalize wood at the level of cell and cell walls one can insert new properties and inevitably upscale them along the intrinsic hierarchical structure, to a level of large-scale engineering materials applications. For this purpose, however, precise control of the spatial distribution of the modifying substances in the complex wood structure is needed. Here we demonstrate a method to insert methacryl groups into wood cell walls using two different chemistry routes. By using these methacryl groups as the anchor points for grafting, various polymers can be inserted into the wood structure. Strikingly, depending on the methacryl precursor, the spatial distribution of the polymer differs strongly. As a proof of concept we grafted polystyrene as a model compound in the second modification step. In the case of methacryloyl chloride the polymer was located mainly at the interface between the cell lumina and the cell wall covering the inner surface of the cells and being traceable up to 2-3 µm in the cell wall, whereas in the case of methacrylic anhydride the polymer was located inside the whole cell wall. Scanning electron microscopy, Fourier transform infrared spectroscopy and especially Raman spectroscopy were used for an in-depth analysis of the modified wood at the cell wall level.


Assuntos
Parede Celular/química , Celulose/química , Reagentes de Ligações Cruzadas/química , Metacrilatos/química , Picea/química , Poliestirenos/química , Madeira/química , Teste de Materiais , Polímeros/química , Propriedades de Superfície , Madeira/ultraestrutura
11.
Neuroscience ; 43(1): 31-4, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1833668

RESUMO

Kainate, an agonist of a unique subclass of glutamate receptors (kainate receptor), was injected intracerebroventricularly in rats to induce convulsive reactions and hippocampal damage in order to model glutamate-mediated brain injury. Rats treated with magnesium sulfate (subcutaneously injected, up to 600 mg/kg) were found to be protected from kainate neurotoxicity depending on the dose and time of application. Results were largely consistent with those obtained previously by using quinolinate as an excitotoxic N-methyl-D-aspartate-receptor agonist. Magnesium is discussed as being a natural and relatively safe therapeutic in cases of glutamate-induced (hypoxic, ischemic, traumatic, or convulsive) disorders of the brain.


Assuntos
Hipocampo/patologia , Ácido Caínico/antagonistas & inibidores , Sulfato de Magnésio/farmacologia , Degeneração Neural/efeitos dos fármacos , Convulsões/induzido quimicamente , Animais , Convulsivantes/farmacologia , Técnicas In Vitro , Injeções Subcutâneas , Ácido Caínico/toxicidade , Sulfato de Magnésio/administração & dosagem , Masculino , Ácido Quinolínico , Ácidos Quinolínicos/farmacologia , Ratos , Ratos Endogâmicos , Convulsões/patologia
12.
J Clin Psychiatry ; 42(7): 264-9, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7240112

RESUMO

electrical seizure activity induced by ECT appears in three phases: Phase I initial 18-22 Hz. (beta-like) activity, Phase II arrhythmic polyspike activity, and Phase III rhythmic 2 1/2-3 1/2 Hz. spike/polyspike-wave activity. With bitemporal ECT, Phase II activity appears simultaneously in all leads. With unilateral non-dominant hemisphere ECT, there is an orderly march on Phase II polyspikes from the right anterior temporal region. After termination of a seizure, there is symmetrical suppression of normal activity with bitemporal ECT, but with unilateral non-dominant hemisphere ECT there is less suppression of normal activity in the unstimulated side.


Assuntos
Eletroconvulsoterapia , Eletroencefalografia , Encéfalo/fisiologia , Transtorno Depressivo/terapia , Humanos
13.
Neuroreport ; 4(2): 205-7, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8453060

RESUMO

To study the penetration of magnesium ions from blood into brain tissue, magnesium content in serum and hippocampus of normal and of excitotoxically affected rats was estimated after a single subcutaneous injection of magnesium sulphate (600 mg kg-1). In normal rats Mg2+ levels in serum rose from 1 to 6 mM, while that of the hippocampus remained constant, provided the brains were perfused before magnesium measurement. Following unilateral intracerebroventricular injection of the excitotoxic glutamate analogues, quinolinate or kainate acid, Mg2+ levels increased up to 38% on the (unaffected) contralateral side. Since magnesium is known to prevent glutamate-mediated neurodegeneration, our findings on the accessibility of exogenously applied magnesium may justify further investigations on the utility of magnesium for a therapeutic approach to limiting excitotoxic brain injury in human patients.


Assuntos
Barreira Hematoencefálica , Ventrículos Cerebrais/fisiologia , Hipocampo/metabolismo , Ácido Caínico/farmacologia , Magnésio/metabolismo , Ácido Quinolínico/farmacologia , Animais , Ventrículos Cerebrais/efeitos dos fármacos , Lateralidade Funcional , Hipocampo/irrigação sanguínea , Hipocampo/efeitos dos fármacos , Injeções Intraventriculares , Ácido Caínico/administração & dosagem , Cinética , Magnésio/sangue , Masculino , Perfusão , Ácido Quinolínico/administração & dosagem , Ratos , Ratos Wistar , Fatores de Tempo
14.
Eur J Pharmacol ; 232(1): 121-4, 1993 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-7681405

RESUMO

alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), an agonist of the non-N-methyl-D-aspartate (NMDA) subtype of the glutamate receptor, was used to imitate glutamate-induced brain injury. A single intracerebroventricular injection of AMPA (9 nmol; 1.7 micrograms) induced convulsive reactions and heavy neurodegeneration in the hippocampal formation. MgSO4 (600 mg/kg), administered 20 min prior to or simultaneously with AMPA exposure, was able to protect completely against this non-NMDA-induced neurotoxicity. Magnesium is suggested to be a hopeful therapeutic principle for glutamate-mediated brain disorders.


Assuntos
Encefalopatias/prevenção & controle , Ácido Ibotênico/análogos & derivados , Magnésio/farmacologia , Convulsões/prevenção & controle , Animais , Encefalopatias/induzido quimicamente , Ácido Ibotênico/antagonistas & inibidores , Masculino , Ratos , Ratos Wistar , Receptores de Glutamato/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Convulsões/induzido quimicamente , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
15.
Neurosci Lett ; 117(1-2): 207-11, 1990 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-2149747

RESUMO

Quinolinate (QUIN), an agonist of the N-methyl-D-aspartate (NMDA) subtype of the glutamate receptor, was used to model glutamate-induced primary or secondary brain damage. Rats intracerebroventricularly injected with QUIN (1 mumol in 2 microliters) showed convulsive reactions and heavy neurodegeneration in the hippocampal formation. MgSO4 (1 M solution injected subcutaneously; 0.6 or 0.3 g/kg) was found to protect completely against QUIN neurotoxicity if administered simultaneously or 1 h after exposure to QUIN. Preliminarily, LD50 for MgSO4 was estimated approximately at 1.2 g/kg. The application of magnesium is discussed to be a potentially powerful therapeutic principle in case of brain injury and convulsive disorders.


Assuntos
Hipocampo/fisiopatologia , Sulfato de Magnésio/farmacologia , Degeneração Neural/efeitos dos fármacos , Neurotoxinas/toxicidade , Ácidos Quinolínicos/toxicidade , Receptores de N-Metil-D-Aspartato/fisiologia , Convulsões/prevenção & controle , Animais , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Sulfato de Magnésio/uso terapêutico , Masculino , Ácido Quinolínico , Ratos , Ratos Endogâmicos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Convulsões/induzido quimicamente
16.
Blood Coagul Fibrinolysis ; 11(1): 27-42, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10691097

RESUMO

The use of libraries of phage-displayed human single-chain antibody fragments (scFv) has become a new, powerful tool in rapidly obtaining therapeutically useful antibodies. Here, we describe the generation of human scFv and F(ab')2 directed against the gamma-carboxyglutamic acid (Gla) domain of coagulation factor IX. A large library of human scFv, displayed either on M13 phage or expressed as soluble proteins, was screened for binding to human Gla-domain peptide (Tyr1-Lys43). Among a panel of scFv that bound to the factor IX-Gla domain, six scFv clones recognized full-length factor IX and exhibited strong inhibitory activity of factor IX in vitro. After reformatting as F(ab')2, the affinity for factor IX of three selected clones was determined: 10C12 Kd = 1.6 nmol/l, 13D1 Kd = 2.9 nmol/l, and 13H6 Kd = 0.46 nmol/l. The antibodies specifically bound to factor IX and not to other coagulation factors, as assessed by enzyme-linked immunosorbent-type and human plasma clotting assays. The complementarity determining region amino acid sequences of clones 10C12 and 13D1 only differed at a single residue, whereas 13H6 showed little homology, suggesting that 13H6 binds to a different epitope within the factor IX-Gla domain. Despite the slightly lower affinity of 10C12 F(ab')2 versus 13H6 F(ab')2, 10C12 was consistently more potent than 13H6 in prolonging the activated partial thromboplastin time (APTT), in inhibiting platelet-mediated plasma clotting, and in inhibiting factor X activation by the intrinsic Xase complex. Finally, 10C12 F(ab')2 also recognized and neutralized factor IX/factor IXa of different species, as demonstrated by the specific APTT prolongation of dog, mouse, baboon and rabbit plasma. In summary, the results validate the usefulness of scFv phage-displayed libraries to rapidly generate fully human antibodies as potential new therapeutics for thrombotic disorders.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/metabolismo , Fator IXa/imunologia , Biblioteca de Peptídeos , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/farmacologia , Afinidade de Anticorpos , Reações Antígeno-Anticorpo/efeitos dos fármacos , Sítios de Ligação de Anticorpos , Ligação Competitiva , Coagulação Sanguínea/efeitos dos fármacos , Fatores de Coagulação Sanguínea/metabolismo , Plaquetas/fisiologia , Cálcio/farmacologia , Bovinos , Clonagem Molecular , Endotélio Vascular/citologia , Ensaio de Imunoadsorção Enzimática , Epitopos/metabolismo , Fator IXa/antagonistas & inibidores , Fator IXa/fisiologia , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Fragmentos Fab das Imunoglobulinas/farmacologia , Região Variável de Imunoglobulina/isolamento & purificação , Região Variável de Imunoglobulina/metabolismo , Região Variável de Imunoglobulina/farmacologia , Magnésio/farmacologia , Dados de Sequência Molecular , Alinhamento de Sequência , Especificidade da Espécie
18.
AACN Clin Issues ; 10(4): 433-41, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10865528

RESUMO

Bilirubin metabolism is a complex and fascinating example of the body's ability to discard, renew, and recycle vital elements. Jaundice is the warning sign for derangements in this system. As is true of pain, jaundice is a powerful impetus for visiting a healthcare provider. Usually associated with hepatitis by a nonclinician, the origins of jaundice can range from benign to fatally malignant. Patients may have any number of idiopathic or nosocomial conditions that can contribute to an icteric state. This review delineates the steps of bilirubin metabolism, enumerates the sources of bilirubin derangement, and examines elements of patient condition and therapeutics that can contribute to hyperbilirubinemia and jaundice.


Assuntos
Icterícia/diagnóstico , Icterícia/etiologia , Bilirrubina/metabolismo , Diagnóstico Diferencial , Humanos , Icterícia/classificação , Icterícia/metabolismo , Avaliação em Enfermagem/métodos , Exame Físico/métodos
19.
J Supramol Struct ; 10(3): 287-305, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-491659

RESUMO

The sialoglycoprotein subunits of human placental brush border membranes were labeled by sequential treatment with periodate and (3H)-sodium borohydride, which trititates sialic acid, and by lactoperoxidase-catalyzed (125I) iodination of tyrosine residues. The labeled subunits were characterized with respect to their affinity for antisera raised against Triton X-100 extracts of placental brush border membranes. The immunochemically reactive components were analyzed by two-dimensional electrophoresis according to a modification of the O'Farrell technique [20] enabling the assignment of estimated Mr and pI. Of the 33 3H-labeled brush border subunits present in Triton X-100-solubilized membrane preparations, 18 subunits reacted with antiplacental brush border antisera insolubilized on CNBr-activated Sepharose or in immunoprecipitates. Fourteen of these tritiated subunits were also labeled with 125I, confirming that these are glycoproteins. The plasma membranes of normal human liver and microsomes from kidney were examined for the placental brush border glycoprotein subunits by reaction with insolubilized antiplacental brush border antisera and two-dimensional electrophoresis of the reacting tritium-labeled subunits. Comparison of the two-dimensional electrophoretic maps of the immunochemically reacting glycoproteins from liver, kidney, and placenta resulted in the identification of seven placental subunits in common with liver and kidney on the basis of antigenic cross-reactivity, Mr, and pI. Four placental glycoproteins were not found in the other tissues and are potentially specific to the placenta. Three of the placental subunits were only seen in placenta and kidney. Three of the subunits ran at the dye front and could not be assigned molecular weights. One of the subunits was poorly labeled by tritiation of sialic acid and was not considered.


Assuntos
Membrana Celular/análise , Rim/análise , Fígado/análise , Microvilosidades/análise , Placenta/análise , Sialoglicoproteínas/análise , Antígenos de Superfície/análise , Fracionamento Celular , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Soros Imunes , Imunoensaio , Substâncias Macromoleculares , Gravidez
20.
Nature ; 318(6047): 665-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3001529

RESUMO

Tumour necrosis factors, TNF-alpha and TNF-beta (previously called lymphotoxin), are the products of activated monocytes and lymphocytes, respectively, and both have recently been purified, sequenced and cloned by recombinant DNA methods, revealing 35% identity and 50% homology in the amino-acid sequence. Both proteins have been found to be specifically toxic to many tumour cells. Furthermore, it has been reported that various interferons are synergistic with TNF for anti-tumour effects in vitro, while activities attributed to the two proteins have also been shown to necrotize various tumours in vivo. We have now prepared 125I-labelled highly purified recombinant human TNF-alpha to study in detail its binding to the human cervical carcinoma cell line ME-180. Our results indicate that there is a single class of specific high-affinity receptors for TNF on this cell line which has a Kd of about 0.2 nM and an average of 2,000 receptor sites per cell. The binding of labelled TNF-alpha to these cells can be inhibited by both TNF-alpha and TNF-beta but not by gamma-interferon (IFN-gamma). However, preincubation of cells with IFN-gamma increases the total number of TNF receptors two to threefold without any significant change in the affinity constant. This is the first report that TNF-alpha and -beta share a common receptor and that the receptors can be up-regulated by interferon. Our results may explain previous observations regarding similar biological activities observed for these two cytotoxic proteins and also their synergistic action with interferons.


Assuntos
Glicoproteínas/metabolismo , Interferon gama/farmacologia , Receptores de Superfície Celular/metabolismo , Linhagem Celular , Feminino , Humanos , Iodo/metabolismo , Peso Molecular , Receptores do Fator de Necrose Tumoral , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Fatores de Tempo , Fator de Necrose Tumoral alfa , Neoplasias do Colo do Útero/análise
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