Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Adv Exp Med Biol ; 1229: 163-180, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32285411

RESUMO

Cardiovascular disease is a leading cause of death worldwide, and with the dramatically increasing numbers of heart failure patients in the next 10 years, mortality will only increase [1]. For patients with end-stage heart failure, heart transplantation is the sole option. Regrettably, the number of available donor hearts is drastically lower than the number of patients waiting for heart transplantation. Despite evidence of cardiomyocyte renewal in adult human hearts, regeneration of functional myocardium after injury can be neglected. The limited regenerative capacity due to inadequate proliferation of existing cardiomyocytes is insufficient to repopulate areas of lost myocardium [2]. As a solution, the hypothesis that adult stem cells could be employed to generate functional cardiomyocytes was proposed. One of the early studies that supported this hypothesis involved direct injection of hematopoietic c-kit-positive cells derived from bone marrow into the infarcted heart [3]. However, in sharp contrast, more recent evidence emerged demonstrating that these hematopoietic stem cells only differentiate into cells down the hematopoietic lineage rather than into cardiomyocytes [4, 5], and the focus shifted towards stem cells residing in the heart, called cardiac progenitor cells. These CPCs were extracted and injected into the myocardium to regenerate the heart [6]. In recent years, over 80 pre-clinical studies employing cardiac stem cells in vivo in large and small animals to evaluate the effect on functional parameters were systematically reviewed, identifying differences between large and small animals [7]. Despite the positive outcome of these stem cell therapies on functional parameters, c-kit-positive cardiac progenitor cells were shown to contribute minimally to the generation of functional cardiomyocytes [8, 9]. This heavily debated topic is summarized concisely by van Berlo and Molkentin [10]. Recently, single-cell sequencing and genetic lineage tracing of proliferative cells in the murine heart in both homeostatic and regenerating conditions did not yield a quiescent cardiac stem cell population or other cell types that support transdifferentiation into cardiomyocytes, nor did it support proliferation of cardiac myocytes [11, 12]. Now, the focus is shifting towards exploiting the limited regenerative capacity of the cardiomyocytes themselves, by re-activating proliferation of existing cardiomyocytes through dedifferentiation, reentry into the cell cycle, and cytokinesis. This process is the new focus of research to promote cardiac regeneration, and can be controlled on multiple levels, including cell-cycle manipulation, reprogramming, small molecules, extra-cellular matrix (ECM), proteins, and RNA regulation [13].


Assuntos
Miocárdio/citologia , Miócitos Cardíacos/citologia , RNA não Traduzido , Regeneração/genética , Animais , Diferenciação Celular , Humanos , Miócitos Cardíacos/transplante , Transplante de Células-Tronco
2.
J Neural Transm (Vienna) ; 122(11): 1573-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26179478

RESUMO

Continuous intrathecal Baclofen application (ITB) through an intracorporeal pump system is widely used in adults and children with spasticity of spinal and supraspinal origin. Currently, about 1200 new ITB pump systems are implanted in Germany each year. ITB is based on an interdisciplinary approach with neurologists, rehabilitation specialists, paediatricians and neurosurgeons. We are presenting the proceedings of a consensus meeting organised by IAB-Interdisciplinary Working Group for Movement Disorders. The ITB pump system consists of the implantable pump with its drug reservoir, the refill port, an additional side port and a flexible catheter. Non-programmable pumps drive the Baclofen flow by the reservoir pressure. Programmable pumps additionally contain a radiofrequency control unit, an electrical pump and a battery. They have major advantages during the dose-finding phase. ITB doses vary widely between 10 and 2000 µg/day. For spinal spasticity, they are typically in the order of 100-300 µg/day. Hereditary spastic paraplegia seems to require particularly low doses, while dystonia and brain injury require particularly high ones. Best effects are documented for tonic paraspasticity of spinal origin and the least effects for phasic muscle hyperactivity disorders of supraspinal origin. Oral antispastics are mainly effective in mild spasticity. Botulinum toxin is most effective in focal spasticity. Myotomies and denervation operations are restricted to selected cases of focal spasticity. Due to its wide-spread distribution within the cerebrospinal fluid, ITB can tackle wide-spread and severe spasticity.


Assuntos
Baclofeno/administração & dosagem , Transtornos dos Movimentos/tratamento farmacológico , Relaxantes Musculares Centrais/administração & dosagem , Espasticidade Muscular/tratamento farmacológico , Alemanha , Humanos , Bombas de Infusão Implantáveis/efeitos adversos , Injeções Espinhais
3.
Nervenarzt ; 82(4): 481-95, 2011 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-21079908

RESUMO

Spasticity is one of the major causes of functional impairment in adults with lesions of the central nervous system. For instance, approximately 30% of post-stroke patients suffer from different degrees of spasticity with possible consecutive impairments. Numerous studies or meta-analyses showed that local injections of botulinum toxin in spastic muscles lead to dose-dependent reduction in muscle tone and improvement of passive movements (e. g. facilitated care), especially following repeated injections.However, country-specific regulations and patient-remote administration in German health care often do not allow adequate provision of this therapy. Thus, the present consensus statement based on the EBM analyses of the published international literature tries to highlight recent advances and the standard in the field of local spasticity treatment, aiming to facilitate communication between the decision makers and German reimbursement institutions in health care. Prior to initiation of BoNT-A injections, patient-oriented goals should be identified in a multiprofessional context to assure realistic goals for this specific treatment and patient expectations. In Germany for the treatment of focal spasticity following stroke three products have been approved: Botox® (Pharm Allergan, Ettlingen), Dysport® (Ipsen Pharma, Ettlingen) and Xeomin® (Merz Pharma, Frankfurt/Main). For all preparations safety has been repeatedly shown. Functional improvements have also been illustrated for selected patients concerning hand/arm function and gait. The dose per muscle and the selection of muscles to be injected have to be individualized according to the patient's symptoms and should be accompanied by modern neurorehabilitative therapies such as redression or repetitive activation of the injected and antagonistic muscles.


Assuntos
Toxinas Botulínicas/uso terapêutico , Espasticidade Muscular/tratamento farmacológico , Neurologia/normas , Guias de Prática Clínica como Assunto , Adulto , Antidiscinéticos/uso terapêutico , Alemanha , Humanos
4.
Neuropsychologia ; 36(1): 77-82, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9533390

RESUMO

While amnesia and other cognitive disturbances are usually caused by structural brain damage, there are a few instances in which environmental stress may induce neuronal death in memory-sensitive brain regions such as the hippocampus. Here we report on a patient who, after a single brief exposure to an event reminding him of a similar stressful event from his childhood, deteriorated immediately and persistently without manifesting structural, but manifesting functional, brain damage as measured by position emission tomography. This patient probably represents the first case in which a direct relation between a single psychic event and the occurrence of brain malfunctioning in cognition is documented by dynamic neuroimaging methods. Psychic shock may cause lasting reductions in brain metabolism with the consequence of severe intellectual malfunctioning.


Assuntos
Amnésia/fisiopatologia , Encéfalo/metabolismo , Transtornos Cognitivos/etiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/fisiopatologia , Humanos , Masculino , Estresse Psicológico , Tomografia Computadorizada de Emissão
5.
J Neurol Sci ; 137(2): 145-9, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8782169

RESUMO

Plasma exchange (PE) and administration of intravenous immunoglobulin (IgG) are established treatments for Guillain-Barré syndrome (GBS). Elimination of postulated pathogenetic factors by plasma exchange or similar methods, such as selective adsorption (SA) treatment using affinity-type adsorption columns and subsequent immunomodulation by intravenous IgG, may provide a more effective treatment. Forty-five patients with acute GBS were prospectively examined using a clinical score. We treated 11 patients by plasma exchange, 13 with selective adsorption using a tryptophan-linked polyvinyl alcohol gel adsorbent, and a group of 21 patients by selective adsorption followed by intravenous IgG. The patients treated sequentially by selective adsorption and intravenous IgG improved significantly better than the patients who received plasma treatment only. This pilot study suggests that sequential treatment of GBS may be superior to plasma treatment alone. The higher cost of this combined treatment might be offset by shorter hospital stays and lower overall expenditure. The preliminary results warrant further investigation in a multicenter trial.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Troca Plasmática , Polirradiculoneuropatia/terapia , Adulto , Terapia Combinada , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
6.
J Agric Food Chem ; 49(10): 5005-12, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11600059

RESUMO

Casein and whey protein were hydrolyzed using 11 different commercially available enzyme preparations. Emulsion-forming ability and emulsion stability of the digests were measured as well as biochemical properties with the objective to study the relations between hydrolysate characteristics and emulsion properties. All whey protein hydrolysates formed emulsions with bimodal droplet size distributions, signifying poor emulsion-forming ability. Emulsion-forming ability of some casein hydrolysates was comparable to that of intact casein. Emulsion instability was caused by creaming and coalescence. Creaming occurred mainly in whey hydrolysate emulsions and in casein hydrolysate emulsions containing large emulsion droplets. Coalescence was dominant in casein emulsions with a broad particle size distribution. Emulsion instability due to coalescence was related to apparent molecular weight distribution of hydrolysates; a relative high amount of peptides larger than 2 kDa positively influences emulsion stability.


Assuntos
Caseínas/química , Emulsões , Proteínas do Leite/química , Estabilidade de Medicamentos , Hidrólise , Peso Molecular , Tamanho da Partícula , Proteínas do Soro do Leite
7.
Ther Apher ; 1(1): 55-7, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10225782

RESUMO

Plasma exchange and administration of intravenous immunoglobulin (IgG) are established treatments for Guillain-Barré syndrome (GBS). Elimination of postulated pathogenetic factors by plasma exchange or selective adsorption treatment using affinity-type adsorption columns and subsequent immunomodulation by intravenous IgG may provide a more effective treatment. Forty-five patients with acute GBS were prospectively examined using a clinical score. We treated 11 patients by plasma exchange, 13 patients by selective adsorption using a tryptophan-linked polyvinyl alcohol gel adsorbent, and 21 patients by selective adsorption followed by intravenous IgG. The patients treated sequentially by selective adsorption and intravenous IgG improved significantly better than the patients who received plasma treatment only. The results suggest that sequential treatment of GBS may be superior to plasma treatment alone. The higher cost of combined treatment may be offset by lower overall expenditure.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Troca Plasmática , Polirradiculoneuropatia/terapia , Doença Aguda , Terapia Combinada , Humanos , Técnicas de Imunoadsorção , Troca Plasmática/métodos , Estudos Prospectivos , Fatores de Tempo
8.
Ther Apher ; 4(3): 195-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10910018

RESUMO

Elimination of circulating antibodies by hemapheresis is an empirical treatment concept in various neuroimmunological diseases. Plasma exchange (PE) has been shown to be superior to symptomatic treatment in Guillain-Barré syndrome (GBS) in two large multicenter studies. It is also effective in myasthenia gravis (MG), although no comparative studies have been performed. Immunoadsorption (IA) using polyvinyl alcohol gel columns to which phenylalanin (IM-PH) or tryptophan (IM-TR) are covalently bound is an alternative to PE, and seems to have equal efficacy and comparable side effects. This method also obviates the need for replacement of plasma with human albumin or plasma. We compared the treatment results of 11 patients with GBS treated by PE to those of 13 patients treated by IA using an IM-TR column. Here, we found no statistically significant differences with regard to efficacy and clinical or procedural complications. From these data we conclude that immunoadsorption can be used as an equal alternative to PE. A large multicenter study comparing PE, intravenous immunoglobulins (IVIG), and the combination of both in the treatment of GBS revealed no significant difference between the 3 treatment groups. In MG, only 2 small studies have been performed using IA, and no studies comparing PE or other treatments to IA have been conducted. Both investigations of IA therapy demonstrated a marked reduction in the acetylcholine receptor (AchR) antibodies and a sustained improvement of the clinical signs. These results therefore show that IA is an effective treatment for myasthenia gravis.


Assuntos
Síndrome de Guillain-Barré/terapia , Técnicas de Imunoadsorção , Miastenia Gravis/terapia , Troca Plasmática , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/imunologia , Humanos , Técnicas de Imunoadsorção/instrumentação , Miastenia Gravis/imunologia , Seleção de Pacientes , Troca Plasmática/instrumentação , Troca Plasmática/métodos , Projetos de Pesquisa , Resultado do Tratamento
9.
Ther Apher ; 4(3): 198-200, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10910019

RESUMO

Plasma exchange (PE) and administration of intravenous immunoglobulin (i.v. IgG) are established treatments for Guillain-Barré syndrome (GBS). Combination treatment with elimination of postulated pathogenetic factors by PE or selective adsorption (SA) treatment and subsequent immunomodulation by intravenous IgG may provide a more effective treatment. In a single-center randomized study, 45 patients with acute GBS were prospectively examined using a clinical score. We treated 11 patients by PE, 13 with SA using a tryptophan-linked polyvinyl alcohol gel adsorbent, and 21 with SA followed by intravenous IgG. The patients treated sequentially by selective adsorption and intravenous IgG improved significantly better than the patients who received plasma treatment only. The results suggest that combination treatment of GBS may be superior to plasma treatment alone.


Assuntos
Síndrome de Guillain-Barré/terapia , Imunoglobulinas Intravenosas/uso terapêutico , Técnicas de Imunoadsorção , Troca Plasmática , Doença Aguda , Terapia Combinada , Pessoas com Deficiência , Síndrome de Guillain-Barré/imunologia , Humanos , Técnicas de Imunoadsorção/instrumentação , Troca Plasmática/instrumentação , Troca Plasmática/métodos , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
10.
Artigo em Inglês | MEDLINE | ID: mdl-10645738

RESUMO

OBJECTIVE: We conducted a follow-up study on a patient with enduring psychic shock-induced cognitive impairment to study by neuropsychological and functional imaging methods the degree of his recovery process on the brain and cognitive levels. BACKGROUND: Based on the assumption that trauma and stress conditions can alter the functions of the nervous systems, we report on a patient whom we studied 2 and 12 months after he suffered "mnestic block syndrome" and additional cognitive deterioration symptoms. METHODS: We report on a patient studied 2 and 12 months after he suffered "mnestic block syndrome" and additional cognitive deterioration symptoms. Magnetic resonance imaging and fluorodeoxyglucose positron emission tomography were used for neural and detailed neuropsychological testing for cognitive deficits. RESULTS: The patient initially manifested severe intellectual decline, including severe anterograde and retrograde amnesia. His symptoms were correlated with major, although selective, reductions in his brain metabolism (2-3 SD below those of controls). Presently, he shows a normal brain metabolism and has regained parts of his memory and many of his other intellectual capabilities. Nevertheless, he still has long-term memory impairments. CONCLUSIONS: This case demonstrates a close relation between brain metabolism and cognitive performance, with major deficits of both at 2 months and major recovery of both at 12 months after a shocking event. It can serve as an example for possible stress-related deteriorations in certain brain regions, which can be partly corrected by psychotherapeutic interventions, passing time, and favorable environmental conditions.


Assuntos
Amnésia/fisiopatologia , Glicemia/metabolismo , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Tomografia Computadorizada de Emissão , Amnésia/diagnóstico por imagem , Amnésia/psicologia , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Inteligência/fisiologia , Masculino , Rememoração Mental/fisiologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/psicologia
11.
J Biol Chem ; 274(37): 26296-304, 1999 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-10473585

RESUMO

A novel nicotinoprotein, catalyzing the dichlorophenolindophenol-dependent oxidation of carveol to carvone, was purified to homogeneity from Rhodococcus erythropolis DCL14. The enzyme is specifically induced after growth on limonene and carveol. Dichlorophenolindophenol-dependent carveol dehydrogenase (CDH) is a homotetramer of 120 kDa with each subunit containing a tightly bound NAD(H) molecule. The enzyme is optimally active at pH 5.5 and 50 degrees C and displays a broad substrate specificity with a preference for substituted cyclohexanols. When incubated with a diastereomeric mixture of (4R)- or (4S)-carveol, CDH stereoselectively catalyzes the conversion of the (6S)-carveol stereoisomers only. Kinetic studies with pure stereoisomers showed that this is due to large differences in V(max)/K(m) values and simultaneous product inhibition by (R)- or (S)-carvone. The R. erythropolis CDH gene (limC) was identified in an operon encoding the enzymes involved in limonene degradation. The CDH nucleotide sequence revealed an open reading frame of 831 base pairs encoding a 277-amino acid protein with a deduced mass of 29,531 Da. The CDH primary structure shares 10-30% sequence identity with members of the short chain dehydrogenase/reductase superfamily. Structure homology modeling with trihydroxynaphthalene reductase from Magnaporthe grisea suggests that CDH from R. erythropolis DCL14 is an alpha/beta one-domain protein with an extra loop insertion involved in NAD binding and a flexible C-terminal part involved in monoterpene binding.


Assuntos
Oxirredutases do Álcool/metabolismo , Rhodococcus/enzimologia , Oxirredutases do Álcool/química , Oxirredutases do Álcool/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Catálise , Clonagem Molecular , DNA Bacteriano , Indução Enzimática , Modelos Moleculares , Dados de Sequência Molecular , NAD/metabolismo , Ligação Proteica , Conformação Proteica , Homologia de Sequência de Aminoácidos , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Especificidade por Substrato
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA