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1.
BMC Genomics ; 16: 559, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26220445

RESUMO

BACKGROUND: Formalin-fixed, paraffin-embedded (FFPE) tissues represent the most abundant resource of archived human specimens in pathology. Such tissue specimens are emerging as a highly valuable resource for translational proteomic studies. In quantitative proteomic analysis, reductive di-methylation of primary amines using stable isotopic formaldehyde variants is increasingly used due to its robustness and cost-effectiveness. RESULTS: In the present study we show for the first time that isotopic amine dimethylation can be used in a straightforward manner for the quantitative proteomic analysis of FFPE specimens without interference from formalin employed in the FFPE process. Isotopic amine dimethylation of FFPE specimens showed equal labeling efficiency as for cryopreserved specimens. For both FFPE and cryopreserved specimens, differential labeling of identical samples yielded highly similar ratio distributions within the expected range for dimethyl labeling. In an initial application, we profiled proteome changes in clear cell renal cell carcinoma (ccRCC) FFPE tissue specimens compared to adjacent non-malignant renal tissue. Our findings highlight increased levels of glyocolytic enzymes, annexins as well as ribosomal and proteasomal proteins. CONCLUSION: Our study establishes isotopic amine dimethylation as a versatile tool for quantitative proteomic analysis of FFPE specimens and underlines proteome alterations in ccRCC.


Assuntos
Aminas/química , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Proteoma/análise , Proteômica , Isótopos de Carbono/química , Carcinoma de Células Renais/metabolismo , Cromatografia Líquida de Alta Pressão , Formaldeído/química , Humanos , Marcação por Isótopo , Neoplasias Renais/metabolismo , Inclusão em Parafina , Espectrometria de Massas em Tandem
2.
Orthopade ; 43(9): 825-32, 2014 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-25135030

RESUMO

BACKGROUND: From an orthopedic point of view, wearing conventional ready to wear shoes negatively affects the front transverse arch of the human foot by forcing it into an unnatural inverted position. OBJECTIVES: The aim of the present orthopedic application study was to conduct a standardized assessment of the biomechanical effect of a newly developed, longitudinally flexible and cross stable spring steel insole by means of pedobarographic measurements and by means of a supplementary questioning of the participants. MATERIAL AND METHODS: In order to do this a total of 33 healthy adult participants were recruited in summer 2013. The randomized, blinded and controlled main study compared the cross stable insole made from spring steel with a flat, ordinary control insole made from ethylene vinyl acetate by means of pedobarographic in-shoe measurements at the forefoot. Additionally, the subjectively perceived effect of the steel insole with respect to comfort, restricted mobility and pain was assessed in a randomized, blinded and controlled ancillary study, using a cross-over design. RESULTS: Both the plantar peak pressure and the plantar force-time integral were significantly higher with the spring steel insole, especially in the central forefoot. In the subsequent test phase lasting several weeks during which the participants were asked to wear the spring steel insole, they rarely complained about problems and in particular did not report negative effects regarding comfort, restricted mobility and pain compared to the ordinary control insoles. CONCLUSION: The present study was conducted according to high methodological standards and proved for the first time that the tested spring steel insoles have a positive effect on the human forefoot. The cross stability increases the pressure in the median ball area, prevents the unnatural inverted position of the forefoot and thus creating an effect which is comparable to walking barefoot. As the participants did not judge this orthopedic effect of the cross stability as being uncomfortable, such an insole could be used a millionfold as a primary prevention in conventional shoes.


Assuntos
Órtoses do Pé , Pé/fisiologia , Marcha/fisiologia , Manometria/métodos , Equilíbrio Postural/fisiologia , Sapatos , Caminhada/fisiologia , Adulto , Método Duplo-Cego , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Desenho de Prótese , Aço , Adulto Jovem
3.
Artigo em Inglês | MEDLINE | ID: mdl-20862379

RESUMO

During the past decades, a large body of information concerning the effects of endocrine disrupting compounds (EDCs) on animals and humans has been accumulated. EDCs are of synthetic or natural origin and certain groups are known to disrupt the action of androgens and to impair the development of the male reproductive tract and external genitalia. The present overview describes the effects of the different classes of EDCs, such as pesticides, phthalates, dioxins, and phytoestrogens, including newly synthesized resveratrol analogs on steroidogenesis in Leydig cells. The potential impact of these compounds on androgen production by Leydig cells during fetal development and in the adult age is discussed. In addition, the possible role of EDCs in connection with the increasing frequency of abnormalities in reproductive development in animals and humans is discussed.


Assuntos
Disruptores Endócrinos , Sistema Endócrino/efeitos dos fármacos , Poluentes Ambientais , Antagonistas de Hormônios/farmacologia , Células Intersticiais do Testículo/fisiologia , Adulto , Animais , Disruptores Endócrinos/efeitos adversos , Sistema Endócrino/embriologia , Sistema Endócrino/fisiologia , Poluentes Ambientais/toxicidade , Hormônios/fisiologia , Humanos , Masculino , Reprodução/efeitos dos fármacos , Maturidade Sexual/efeitos dos fármacos
4.
Horm Res Paediatr ; 73(2): 93-101, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20190545

RESUMO

Sex steroids are crucial regulators of sexual differentiation and the proper development of secondary sex characteristics and patterns of sexual behavior. Since Leydig cells are the primary major producers of these steroid hormones, maintenance of the normal functions of these cells determines the reproductive capacity and fertility of males. The present minireview discusses recent findings concerning endocrine and paracrine regulation of the proliferation, differentiation and involution of human Leydig cells. The physiology and function of the two distinct fetal and adult populations of human Leydig cells are described, with particular focus on the paracrine environment that triggers their differentiation and functional maturation. The roles of established and more recently discovered paracrine regulators of this maturation, including insulin-like factor 3, platelet-derived growth factor-alpha, desert hedgehog, ghrelin and leptin are considered. A brief description of the origin, ontogenesis and functional markers of human fetal and adult Leydig cells is presented.


Assuntos
Hormônios Esteroides Gonadais/fisiologia , Células Intersticiais do Testículo , Adulto , Biomarcadores , Diferenciação Celular , Proliferação de Células , Feto , Grelina/fisiologia , Proteínas Hedgehog/fisiologia , Humanos , Insulina/fisiologia , Leptina/fisiologia , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/fisiologia , Masculino , Comunicação Parácrina , Fator de Crescimento Derivado de Plaquetas/fisiologia , Proteínas/fisiologia , Diferenciação Sexual/fisiologia
5.
J Biomed Mater Res B Appl Biomater ; 90(1): 55-66, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18985775

RESUMO

In this work, a novel bioresorbable bone adhesive based on radically polymerizable polylactide with methacrylate endgroups known from polymethylmethacrylate (PMMA) cements and varying amounts of bioresorbable/biodegradable lactide moieties was developed. The swelling and degradation properties as well as the hardening time, viscosity, and adhesion properties (tension and shear resistance) were subsequently measured in vitro and optimized. For a broad use in surgery the handling properties, the shelf life and the storage temperature are important issues. The finally developed material consists of three substances that have to be mixed to start the reaction: a highly viscous mixture of oligomers and two beta-tricalcium phosphate (beta-TCP, Cerasorb) powders with the radical starter and the promoter. The material has a processing time of 2 min and is completely cured after another minute. The tension and shear resistance of the material is 3.1-13.9 MPa that will decrease by storing the substance in a humid atmosphere. Degradation experiments showed a mass loss of 20-35% during the first 5 weeks. Tests with MC3T3-E1 cells showed an increase of the alkaline phosphatase activity over a period of 14 days. The mechanical and handling properties and the in vitro data are showing a promising biomaterial for bone regeneration.


Assuntos
Materiais Biocompatíveis , Cimentos Ósseos , Fosfatos de Cálcio/química , Metacrilatos/química , Células 3T3 , Animais , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Biomed Mater Eng ; 15(1-2): 73-85, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15623932

RESUMO

Novel difunctional oligolactone macromers have been synthesized by ring-opening oligomerization of various lactones (L-lactide, glycolide, p-dioxanone) in the presence of suitable diols (propane-1,2-diol, dianhydro-D-glucitol) and subsequent endcapping of the formed oligolactones with methacrylate moieties. Based on these macromers, two fabrication procedures were developed to fabricate highly porous scaffolds and the material properties including in vitro biodegradation behaviour of the resulting polymeric scaffolds were investigated. Preliminary in vitro studies on the cytocompatibility of the fabricated scaffolds and on osteoblast cultivation on the optimized polymeric materials demonstrated that the oligolactide based polymer networks possess an excellent biocompatibility and that they are promising candidates as scaffolds in bone tissue engineering.


Assuntos
Implantes Absorvíveis , Bioprótese , Substitutos Ósseos , Lactonas/química , Osteoblastos/citologia , Osteoblastos/fisiologia , Engenharia Tecidual/métodos , Células 3T3 , Animais , Adesão Celular/fisiologia , Proliferação de Células , Sobrevivência Celular/fisiologia , Teste de Materiais , Camundongos , Peso Molecular , Porosidade , Desenho de Prótese
7.
Osteoarthritis Cartilage ; 9 Suppl A: S48-54, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11680688

RESUMO

OBJECTIVE: Novel approaches to intervention in joint diseases consist of the replacement of diseased cartilage by in vitro engineered, viable cells or graft tissues. Two major obstacles remain to be overcome: (1) Hyaline cartilage in vitro often loses differentiated traits. (2) Grafts frequently are not integrated satisfactorily into host cartilage and/or the tissue is remodelled in situ into functionally inferior fibrocartilage. Therefore, we have explored the possibility whether chondrocytes embedded into agarose gels provided better graft tissues in a repair model of full thickness defects in rabbit joint cartilage. DESIGN: Experimental defects of knee joint cartilage was filled with articular chondrocytes cultured in agarose gels. Chondrocytes in vitro either remained unstimulated or were treated with several growth factors. Repair of the defects was assessed by histology and was scored between 0 (no healing) and 1 (perfect healing) as judged by the follwing parameters: intensity of proteoglycan staining, organization of the superficial zone, ossification at the border between repair cartilage and subchondral bone, tidemark formation in the repaired area, arrangement of chondrocytes, and integration of repair cartilage into host. RESULTS: Treatment of chondrocyte cultures with bFGF had a stabilizing effect on the differentiated state of the cells in implanted grafts whereas bone morphogenetic proteins stimulated ingrowth of subchondral bone reducing repair cartilage thickness and preventing normal tide mark formation; TGF-beta did not significantly affect evaluation parameters in comparison with untreated controls. CONCLUSION: Growth factor treatment resulted in an ambiguous quality of graft development. Only FGF had a clear beneficial effect to the graft tissues after 1 month. Further studies are required to define the precise conditions and sequence of growth factor treatment of in vitro engineered cartilage which benefits graft quality.


Assuntos
Cartilagem Articular/fisiologia , Condrócitos/fisiologia , Substâncias de Crescimento/fisiologia , Sefarose/fisiologia , Animais , Proteínas Morfogenéticas Ósseas/fisiologia , Cartilagem Articular/citologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Feminino , Fatores de Crescimento de Fibroblastos/fisiologia , Coelhos , Estatísticas não Paramétricas , Fator de Crescimento Transformador beta/fisiologia , Cicatrização/fisiologia
8.
Basic Res Cardiol ; 96(2): 198-205, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11327339

RESUMO

Myocardial contractility depends on temperature. We investigated the influence of mild hypothermia (37-31 degrees C) on isometric twitch force, sarcoplasmic reticulum (SR) Ca2+-content and intracellular Ca2+-transients in ventricular muscle strips from human and porcine myocardium, and on in vivo hemodynamic parameters in pigs. In vitro experiments: muscle strips from 5 nonfailing human and 8 pig hearts. Electrical stimulation (1 Hz), simultaneous recording of isometric force and rapid cooling contractures (RCCs) as an indicator of SR Ca2+-content, or intracellular Ca2+-transients (aequorin method). In vivo experiments: 8 pigs were monitored with Millar-Tip (left ventricle) and Swan-Ganz catheter (pulmonary artery). Hemodynamic parameters were assessed at baseline conditions (37 degrees C), and after stepwise cooling on cardiopulmonary bypass to 35, 33 and 31 degrees C. Hypothermia increased isometric twitch force significantly by 91 +/- 16 % in human and by 50 +/- 9 % in pig myocardium (31 vs. 37 degrees C; p < 0.05, respectively). RCCs or aequorin light emission did not change significantly. In anesthetized pigs, mild hypothermia resulted in an increase in hemodynamic parameters of myocardial contractility. While heart rate decreased from 111 +/- 3 to 73 +/- 1 min(-1), cardiac output increased from 2.4 +/- 0.1 to 3.1 +/- 0.31/min, and stroke volume increased from 21 +/- 1 to 41 +/- 3 ml. +dP/dtmax increased by 25 +/- 8% (37 vs. 31 degrees C; p < 0.05 for all values). Systemic and pulmonary vascular resistance did not change significantly during cooling. Mild hypothermia exerts significant positive inotropic effects in human and porcine myocardium without increasing intracellular Ca2+-transients or SR Ca2+-content. These effects translate into improved hemodynamic parameters of left ventricular function.


Assuntos
Circulação Coronária/fisiologia , Hipotermia Induzida , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Equorina , Animais , Cálcio/metabolismo , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Técnicas In Vitro , Contração Isométrica/fisiologia , Volume Sistólico/fisiologia , Suínos , Resistência Vascular/fisiologia , Pressão Ventricular/fisiologia
9.
Cardiovasc Res ; 50(3): 486-94, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11376624

RESUMO

OBJECTIVE: Protein kinase C (PKC) is thought to be involved in the regulation of the mammalian cardiac excitation-contraction coupling process by vasoactive peptides like endothelin-1 (ET-1). However, the demonstration of a causal link between activation of specific PKC isoforms and the increase in contractility mediated by ET-1 is still inferential. METHODS: By means of adenovirus-mediated gene transfer, we specifically overexpressed PKC epsilon in cultured adult rabbit ventricular myocytes (Ad-PKC epsilon). Myocyte shortening and [Ca2+]i transients under basal and ET-1-stimulated conditions were measured in Ad-PKC epsilon and Ad-LacZ control transfected cells. RESULTS: Infection with Ad-PKC epsilon resulted in a strong, virus dose-dependent increase in PKC epsilon protein levels, whereas protein expression of other PKC isoforms remained unchanged. Using a multiplicity of infection of 100 plaque-forming units/myocyte, basal and cofactor-dependent PKC epsilon kinase activity was increased 28- and 90-fold, respectively, when compared to control. Myocyte basal fractional shortening and [Ca2+]i transient amplitude were both increased by 21% (P < 0.05 each) in Ad-PKC epsilon transfected myocytes when compared to Ad-LacZ transfected control myocytes. The positive inotropic effect of ET-1 in control myocytes was markedly blunted in PKC epsilon-overexpressing myocytes. CONCLUSION: Specific overexpression of PKC epsilon in rabbit ventricular myocytes increases basal myocyte contractility and [Ca2+]i transients, and modifies their responsiveness to ET-1.


Assuntos
Cardiotônicos/farmacologia , Endotelina-1/farmacologia , Contração Miocárdica/fisiologia , Miocárdio/enzimologia , Proteína Quinase C/metabolismo , Adenoviridae/genética , Animais , Cálcio/metabolismo , Técnicas de Cultura de Células , Relação Dose-Resposta a Droga , Técnicas de Transferência de Genes , Vetores Genéticos , Ventrículos do Coração/citologia , Ventrículos do Coração/enzimologia , Contração Miocárdica/efeitos dos fármacos , Coelhos
10.
J Cereb Blood Flow Metab ; 21(4): 396-403, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11323525

RESUMO

Large-conductance, calcium-activated potassium (maxi-K) channels regulate neurotransmitter release and neuronal excitability, and openers of these channels have been shown to be neuroprotective in models of cerebral ischemia. The authors evaluated the effects of postinjury systemic administration of the maxi-K channel opener, BMS-204352, on behavioral and histologic outcome after lateral fluid percussion (FP) traumatic brain injury (TBI) in the rat. Anesthetized Sprague-Dawley rats (n = 142) were subjected to moderate FP brain injury (n = 88) or surgery without injury (n = 54) and were randomized to receive a bolus of 0.1 mg/kg BMS-204352 (n = 26, injured; n = 18, sham), 0.03 mg/kg BMS-204352 (n = 25, injured; n = 18, sham), or 2% dimethyl sulfoxide (DMSO) in polyethylene glycol (vehicle, n = 27, injured; n = 18, sham) at 10 minutes postinjury. One group of rats was tested for memory retention (Morris water maze) at 42 hours postinjury, then killed for evaluation of regional cerebral edema. A second group of injured/sham rats was assessed for neurologic motor function from 48 hours to 2 weeks postinjury and cortical lesion area. Administration of 0.1 mg/kg BMS-204352 improved neurologic motor function at 1 and 2 weeks postinjury (P < 0.05) and reduced the extent of cerebral edema in the ipsilateral hippocampus, thalamus, and adjacent cortex (P < 0.05). Administration of 0.03 mg/kg BMS-204352 significantly reduced cerebral edema in the ipsilateral thalamus (P < 0.05). No effects on cognitive function or cortical tissue loss were observed with either dose. These results suggest that the novel maxi-K channel opener BMS-204352 may be selectively beneficial in the treatment of experimental TBI.


Assuntos
Edema Encefálico/tratamento farmacológico , Lesões Encefálicas/tratamento farmacológico , Indóis/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Canais de Potássio Cálcio-Ativados , Canais de Potássio/metabolismo , Animais , Química Encefálica/efeitos dos fármacos , Edema Encefálico/mortalidade , Edema Encefálico/patologia , Lesões Encefálicas/mortalidade , Lesões Encefálicas/patologia , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/mortalidade , Transtornos Cognitivos/patologia , Modelos Animais de Doenças , Canais de Potássio Ativados por Cálcio de Condutância Alta , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Neurônios Motores/fisiologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos
11.
J Mol Cell Cardiol ; 32(9): 1595-607, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10966823

RESUMO

Progressive deterioration of cardiac contractility is a central feature of congestive heart failure (CHF) in humans. In this report we review those studies that have addressed the idea that alterations of intracellular calcium (Ca(2+)) regulation is primarily responsible for the depressed contractility of the failing heart. The review points out that Ca(2+)transients and contraction are similar in non-failing and failing myocytes at very slow frequencies of stimulation (and other low stress environments). Faster pacing rates, high Ca(2+)and beta-adrenergic stimulation reveal large reductions in contractile reserve in failing myocytes. The underlying cellular basis of these defects is then considered. Studies showing changes in the abundance of L-type Ca(2+)channels, Ca(2+)transport proteins [sarcoplasmic reticulum Ca(2+)ATPase (SERCA2), phospholamban (PLB), Na(+)/Ca(2+) exchanger (NCX)] and Ca(2+) release channels (RYR) in excitation-contraction coupling and Ca(2+)release and uptake by the sarcoplasmic reticulum (SR) are reviewed. These observations support our hypotheses that (i) defective Ca(2+)regulation involves multiple molecules and processes, not one molecule, (ii) the initiation and progression of CHF inolves defective Ca(2+)regulation, and (iii) prevention or correction of Ca(2+)regulatory defects in the early stages of cardiac diseases can delay or prevent the onset of CHF.


Assuntos
Cálcio/metabolismo , Cardiomegalia/metabolismo , Insuficiência Cardíaca/metabolismo , Humanos , Retículo Sarcoplasmático/metabolismo , Transdução de Sinais
12.
Am J Physiol Heart Circ Physiol ; 279(3): H952-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10993755

RESUMO

Physiologically, human atrial and ventricular myocardium are coupled by an identical beating rate and rhythm. However, contractile behavior in atrial myocardium may be different from that in ventricular myocardium, and little is known about intracellular Ca(2+) handling in human atrium under physiological conditions. We used rapid cooling contractures (RCCs) to assess sarcoplasmic reticulum (SR) Ca(2+) content and the photoprotein aequorin to assess intracellular Ca(2+) transients in atrial and ventricular muscle strips isolated from nonfailing human hearts. In atrial myocardium (n = 19), isometric twitch force frequency dependently (0. 25-3 Hz) increased by 78 +/- 25% (at 3 Hz; P < 0.05). In parallel, aequorin light signals increased by 111 +/- 57% (P < 0.05) and RCC amplitudes by 49 +/- 13% (P < 0.05). Similar results were obtained in ventricular myocardium (n = 13). SR Ca(2+) uptake (relative to Na(+)/Ca(2+) exchange) frequency dependently increased in atrial and ventricular myocardium (P < 0.05). With increasing rest intervals (1-240 s), atrial myocardium (n = 7) exhibited a parallel decrease in postrest twitch force (at 240 s by 68 +/- 5%, P < 0.05) and RCCs (by 49 +/- 10%, P < 0.05). In contrast, postrest twitch force and RCCs significantly increased in ventricular myocardium (n = 6). We conclude that in human atrial and ventricular myocardium the positive force-frequency relation results from increased SR Ca(2+) turnover. In contrast, rest intervals in atrial myocardium are associated with depressed contractility and intracellular Ca(2+) handling, which may be due to rest-dependent SR Ca(2+) loss (Ca(2+) leak) and subsequent Ca(2+) extrusion via Na(+)/Ca(2+) exchange. Therefore, the influence of rate and rhythm on mechanical performance is not uniform in atrial and ventricular myocardium.


Assuntos
Cálcio/metabolismo , Átrios do Coração/metabolismo , Miocárdio/metabolismo , Equorina/genética , Equorina/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Estimulação Elétrica , Ventrículos do Coração/metabolismo , Humanos , Técnicas In Vitro , Líquido Intracelular/metabolismo , Contração Isométrica/fisiologia , Medições Luminescentes , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Tempo de Reação/fisiologia , Retículo Sarcoplasmático/metabolismo , Sódio/metabolismo
13.
J Neurotrauma ; 17(1): 83-91, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10674760

RESUMO

Experimental traumatic brain injury (TBI) initiates massive disturbances in Ca2+ concentrations in the brain that may contribute to neuronal damage. Intracellular Ca2+ may be elevated via influx through voltage-operated cation channels, ligand-gated ionotropic channels, and store-operated cation channels (SOCs). In the present study, we evaluated the neurobehavioral and histological effects of acute posttraumatic administration of (R,S)-(3,4-dihydro-6,7-dimethoxy-isoquinoline-1-yl)-2-phenyl-N,N-di[2-(2 ,3,4-trimethoxyphenyl)ethyl]-acetamide (LOE 908), a broad spectrum inhibitor of voltage-operated cation channels and SOCs. Male Sprague-Dawley rats (n = 53) were trained in the Morris water maze, anesthetized (60 mg/kg pentobarbital, i.p.), and subjected to lateral fluid percussion brain injury (2.5-2.7 atm; n = 38) or surgery without injury (n = 15). At 15 min postinjury, animals were randomized to receive intravenous administration of either a high dose of LOE 908 (4 mg/kg bolus followed by 160 mg/kg over 24 h; n = 13), a low dose of LOE 908 (2 mg/kg bolus followed by 80 mg/kg over 24 h; n = 12), or vehicle (n = 13). Uninjured controls received the high dose of LOE 908 (n = 8) or vehicle (n = 7). Treatment with either dose of LOE 908 significantly improved neuromotor function at 48 h postinjury when compared to vehicle treatment. Although a significant deficit in visuospatial memory was observed in brain-injured animals at this timepoint when compared to uninjured animals, neither dose of LOE 908 attenuated injury-induced cognitive dysfunction. Histological evaluation revealed that neither dose of LOE 908 affected cortical lesion size at 48 h postinjury. These data suggest that broad spectrum cation channel blockers may be beneficial in the treatment of neurological motor dysfunction when administered in the acute posttraumatic period.


Assuntos
Acetamidas/administração & dosagem , Lesões Encefálicas/tratamento farmacológico , Córtex Cerebral/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Isoquinolinas/administração & dosagem , Transtornos das Habilidades Motoras/tratamento farmacológico , Ferimentos não Penetrantes/tratamento farmacológico , Acetamidas/sangue , Animais , Lesões Encefálicas/sangue , Lesões Encefálicas/complicações , Cateterismo , Córtex Cerebral/lesões , Córtex Cerebral/patologia , Transtornos Cognitivos/etiologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Isoquinolinas/sangue , Masculino , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/etiologia , Transtornos das Habilidades Motoras/etiologia , Exame Neurológico , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Ferimentos não Penetrantes/sangue , Ferimentos não Penetrantes/complicações
14.
Trends Cardiovasc Med ; 10(3): 101-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11427996

RESUMO

Reduced peak systolic Ca2+ and slow decay of the Ca2+ transient are common features of the end-stage failing human ventricular myocyte and are thought to underlie abnormal ventricular contractility in congestive heart failure (CHF). Individual changes in the expression or activity of Ca2+ transport proteins of the sarcoplasmic reticulum (SR Ca2+ ATPase, SERCa) or the sarcolemmal (sodium-calcium exchanger, NCX) have not always been observed in CHF and cannot per se consistently explain these Ca2+ transient defects. We review recent data that suggests that the normal balance of transport activities of SERCa and NCX is deranged in failing human myocytes. We hypothesize that an increase in the NCX/SERCa transport capacity in failing myocytes can explain the abnormal Ca2+ homeostasis of the failing human ventricular myocyte.


Assuntos
Cálcio/metabolismo , Insuficiência Cardíaca/fisiopatologia , Miocárdio/metabolismo , Potenciais de Ação , ATPases Transportadoras de Cálcio/metabolismo , Estimulação Elétrica , Insuficiência Cardíaca/metabolismo , Homeostase , Humanos , Contração Miocárdica/fisiologia , Retículo Sarcoplasmático/metabolismo , Trocador de Sódio e Cálcio/metabolismo
15.
J Pharmacol Toxicol Methods ; 41(1): 9-15, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10507753

RESUMO

A brief period of ischemia was used to evaluate an erythrocyte-enriched Krebs-Henseleit (KH) buffer (n=8) compared to KH only (n=8) in an isolated working rabbit heart. Experimental protocol was as follows: preischemic baseline, 5 min of global ischemia followed by 45 min of reperfusion. Preischemic heart rate was identical, coronary flow was significantly lower (2.7 versus 5.6 mL/min/g wet wt, p<0.01), the other hemodynamic and biochemical values were significantly higher in erythrocyte-perfused hearts: aortic flow 23.5 versus 12.0, p<0.01; cardiac output 26.2 versus 17.6, p<0.01; all in mL/min/g wet wt; dp/dt max 1286 versus 997 mmHg/s, p<0.01; myocardial oxygen consumption 3.5 versus 2.3 micromol/min/g wet wt, p<0.05. During early reperfusion, in the erythrocyte-perfused hearts, coronary flow further increased (p<0.003), the other hemodynamic parameters returned to baseline values in both groups. High-energy phosphates showed significantly higher values (ATP 2.0+/-0.1 versus 1.3+/-0.1, p<0.05; CrP 2.0+/-0.2 versus 1.6+/-0.1, p<0.05 all in micromol/g wct wt), water content was significantly lower (81% versus 74%, p<0.05) in erythrocyte-perfused hearts. It can be concluded that the erythrocyte-perfused working heart model provides excellent oxygenation, leading to superior hemodynamic and metabolic performance. Additionally, in the erythrocyte-perfused hearts preservation of coronary flow reserve underlines the physiological competency of this preparation.


Assuntos
Eritrócitos/fisiologia , Coração/fisiologia , Hemodinâmica/fisiologia , Modelos Cardiovasculares , Perfusão/métodos , Nucleotídeos de Adenina/metabolismo , Animais , Água Corporal/metabolismo , Soluções Tampão , Vasos Coronários/fisiologia , Técnicas In Vitro , Masculino , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/metabolismo , Consumo de Oxigênio , Perfusão/instrumentação , Coelhos , Resistência Vascular/fisiologia
16.
J Neurochem ; 73(1): 271-80, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10386980

RESUMO

Experimental evidence suggests that magnesium plays a role in the pathophysiological sequelae of brain injury. The present study examined the variation of blood ionized and total magnesium, as well as potassium, sodium, and ionized calcium, after experimental fluid percussion brain injury in rats. Blood ionized magnesium concentration significantly declined from 0.45 +/- 0.02 to 0.32 +/- 0.02 mM by 30 min postinjury and stayed depressed for the 24-h study period in vehicle-treated rats. Blood total magnesium concentration was 0.59 +/- 0.01 mM and remained stable over time in brain-injured vehicle-treated animals. When magnesium chloride (125 micromol/rat) was administered 1 h postinjury, ionized magnesium levels were restored by 2 h postinjury and remained at normal values up to 24 h following brain trauma. Magnesium treatment also significantly reduced posttraumatic neuromotor impairments 1 and 2 weeks after the insult, but failed to attenuate spatial learning deficits. A significant positive and linear correlation could be established between ionized magnesium levels measured 24 h postinjury and neuromotor outcome at 1 and 2 weeks. We conclude that acute ionized magnesium measurement may be a predictor of long-term neurobehavioral outcome following head injury and that delayed administration of magnesium chloride can restore blood magnesium concentration and attenuate neurological motor deficits in brain-injured rats.


Assuntos
Lesões Encefálicas/sangue , Cloreto de Magnésio/uso terapêutico , Magnésio/sangue , Sistema Nervoso/fisiopatologia , Animais , Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Cálcio/sangue , Cátions Bivalentes , Cognição , Aprendizagem , Masculino , Atividade Motora , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/prevenção & controle , Ratos , Ratos Sprague-Dawley
17.
Osteoarthritis Cartilage ; 6(1): 50-65, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9616439

RESUMO

OBJECTIVE: Durable healing of full-thickness articular cartilage defects has been considered for a long time as a highly desirable, but unlikely event to occur. In recent years, conflicting reports on the outcome of in vitro and in vivo studies on chondrocyte and cartilage grafting into animal and human joints have raised new arguments for and against controlled repair of articular cartilage following injury. Some of the problems result from insufficient characterization of implant and repair tissue, and from too short follow up phases. Here we describe a new approach to repair articular cartilage defects in rabbit knees by allografting chondrocytes cultured in agarose gels. DESIGN: The implants were monitored over 6-18 months and graded histologically, immunohistochemically, and electron microscopically, using a grading scale based on seven evaluation criteria. Control implants of pure agarose produced poor fibrous substitute tissue, insufficient healing and incomplete filling of the cartilage defects. After transplantation of allogenic chondrocytes embedded in agarose, the quality of the newly formed repair cartilage was superior with respect to type II collagen and proteoglycan content and cellular architecture when compared with untreated defects. Superficial fibrillation and degradation were significantly diminished or prevented. RESULTS: New subchondral bone formed at the level of the previous subchondral bone. In most cases the repair tissue merged with the host articular cartilage; normal calcified cartilage was the only tissue zone that did not participate in the integration of the transplant. By gross evaluation 24% of grafts showed an extent of recovery never observed in controls. The best results were obtained after 18 months when 47% of the grafts (N = 15) developed a morphologically stable hyaline cartilage. CONCLUSION: These studies demonstrate that agarose-embedded chondrocyte may prove a valuable tool for controlled repair of articular cartilage defects.


Assuntos
Ágar , Cartilagem Articular/lesões , Condrócitos/transplante , Traumatismos do Joelho/terapia , Cicatrização , Animais , Cartilagem Articular/ultraestrutura , Técnicas de Cultura de Células , Traumatismos do Joelho/patologia , Coelhos , Transplante Homólogo
18.
Klin Padiatr ; 205(2): 124-6, 1993.
Artigo em Alemão | MEDLINE | ID: mdl-8487480

RESUMO

Glutaracidemia/glutaraciduria type I is an acute or subacute neuropathic disorder of infancy or early childhood. The following symptoms characterize the clinical course: macrocephalus present at birth, cerebral atrophy revealed by CT or MRI scans, most striking in the frontal and temporal lobes, choreoathetosis and dystonia as neurological handicaps. The deficiency of glutaryl-CoA-dehydrogenase leads to glutaracidemia and glutaraciduria. It is reported on a three year old girl. The glutaraciduria is an important differential diagnosis to chorea minor.


Assuntos
Coreia/genética , Glutaratos/sangue , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Oxirredutases/deficiência , Pré-Escolar , Diagnóstico Diferencial , Feminino , Glutaril-CoA Desidrogenase , Humanos , Imageamento por Ressonância Magnética , Exame Neurológico , Oxirredutases/genética
19.
Comp Biochem Physiol B ; 101(1-2): 225-30, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1379897

RESUMO

1. The RNA synthesis of V79-E cells was inhibited by the mycotoxin citrinin time- and concentration-dependently. 2. Among the different RNA species mainly the rRNA synthesis was found to be inhibited by 200 microM citrinin. 3. At different precursor concentrations DNA synthesis was inhibited by citrinin after 30 min at least whereas labelling of the acid soluble fractions was found to be 3-fold higher than in untreated cells. 4. Remarkable perturbation of the DNA precursor metabolism, including release of precursor into the medium, was found to occur during citrinin treatment.


Assuntos
Citrinina/farmacologia , DNA/biossíntese , RNA/biossíntese , Animais , Linhagem Celular , Citrinina/química , Cricetinae , DNA/efeitos dos fármacos , DNA/metabolismo , Cinética , Estrutura Molecular , RNA/efeitos dos fármacos
20.
Monatsschr Kinderheilkd ; 139(11): 754-8, 1991 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1775140

RESUMO

Glutaric aciduria type I is due to an impaired glutaryl-CoA-dehydrogenase with an increased urinary excretion of glutaric and 3-OH glutaric acid. Typically, the clinical course until the sixth month or even 3rd year of life is symptom free, and only later an encephalopathic crisis develops. The only symptom of our 4 patients was macrocephaly (head circumference greater than 97. percentile) in early infancy. 3 of them suffered from an encephalopathic crisis at 8 months to 3 years of age; during that time they lost already established abilities as sitting, walking and speaking, and developed choereoathetotic movements. One child aged 15 months was normal beside it's macrocephalus. All children were treated with a diet low in lysine (80 mg/kg BW/day), tryptophane (21 mg/kg BW/day), and by supplementation of L-carnitine (200 mg/kg BW/day) and riboflavine (200 mg/day) and the motorically disturbed children received Lioresal 1 mg/kg BW/day. The effect of this treatment cannot be evaluated so far, but there is evidence that the dietetic therapy together with carnitine supplementation may prevent further deterioration in affected, or an encephalopathic crisis in unaffected patients. Therefore we suggest to investigate organic acids in urine in every child or infant with macrocephalus to exclude glutaric aciduria type I.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Aberrações Cromossômicas/genética , Genes Recessivos/genética , Glutaratos/urina , Hidrocefalia/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Oxirredutases/deficiência , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Cefalometria , Pré-Escolar , Transtornos Cromossômicos , Terapia Combinada , Ecoencefalografia , Feminino , Seguimentos , Glutaril-CoA Desidrogenase , Humanos , Hidrocefalia/enzimologia , Lactente , Masculino , Oxirredutases/genética , Tomografia Computadorizada por Raios X
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