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1.
Injury ; 49 Suppl 3: S2-S7, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30415665

RESUMO

INTRODUCTION: The incidence of nonunion after fractures of the distal femur is up to 6%. The distal femoral nonunion is a disabling disease that needs complex steps in his treatment. Aim of our study is to find predicting factors of non-unions. MATERIALS AND METHODS: We retrospectively analyzed 116 cases of distal femoral fractures and 20 cases of non-unions. In both surgeries we analyzed: accuracy of reduction, stability of fixation, hardware used, residual medial or lateral bone defect, use of autologous or heterologous bone grafts. RESULTS: Malreduction, particularly axial defect, associated with unbalanced fixation, and a medial cortical bone defect of greater or lesser extent were found to be the major risk factors of nonunion. Addressing both the mechanical and the biological environment was associated with successful non union treatment. CONCLUSION: The main principles for solving a distal femoral nonunion are new better reduction, correction of the medial bone defect and biological support with bone grafting. From the mechanical side the association of a medial strut graft or a medial column plate could be very useful in the treatment of these non-unions.


Assuntos
Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas , Fraturas não Consolidadas/cirurgia , Complicações Pós-Operatórias/cirurgia , Adulto , Idoso , Fenômenos Biomecânicos , Placas Ósseas , Transplante Ósseo , Feminino , Fraturas do Fêmur/fisiopatologia , Fixação Interna de Fraturas/efeitos adversos , Consolidação da Fratura/fisiologia , Fraturas não Consolidadas/etiologia , Fraturas não Consolidadas/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , Amplitude de Movimento Articular , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Falha de Tratamento , Adulto Jovem
2.
Br J Pharmacol ; 171(4): 995-1006, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24224799

RESUMO

BACKGROUND AND PURPOSE: The GABAB receptor agonist baclofen reduces urethral resistance and detrusor overactivity in patients with spasticity. However, baclofen's side effects limit its use for the treatment of overactive bladder (OAB). Here, we tested a novel GABAB positive allosteric modulator (PAM) ADX71441 in models of OAB in mice and guinea pigs. EXPERIMENTAL APPROACH: Mice were left untreated or given (p.o.) vehicle (1% CMC), ADX71441 (1, 3, 10 mg kg(-1) ) or oxybutynin (100 mg kg(-1) ; Experiment 1) or vehicle (1% CMC), baclofen (1, 3, 6 mg kg(-1) ) or oxybutynin (Experiment 2). Treated mice were then overhydrated with water, challenged with furosemide, before being placed into micturition chambers and monitored for urinary parameters. In anaesthetized guinea pigs, intravesical infusion of acetic acid was used to induce OAB and the effects of ADX71441 (1, 3 mg kg(-1) ) or baclofen (1 mg kg(-1) ), administered i.v., on cystometric parameters were monitored. KEY RESULTS: In mice, 10 mg kg(-1) ADX71441 increased urinary latencies, reduced the number of urinary events and the total and average urinary volumes. In guinea pigs, ADX71441 (1 and 3 mg kg(-1) ) increased the intercontraction interval (ICI) and bladder capacity (BC), and reduced micturition frequency (MF) compared to vehicle. At 3 mg kg(-1) ADX71441 completely inhibited the micturition reflex and induced overflow incontinence in five out of 10 animals. Baclofen slightly increased ICI and BC and reduced MF. CONCLUSION AND IMPLICATIONS: Our findings demonstrate, for the first time, that a GABAB PAM has potential as a novel approach for the treatment of OAB.


Assuntos
Proteínas de Bactérias/uso terapêutico , Receptores de GABA-B/metabolismo , Fatores de Transcrição/uso terapêutico , Bexiga Urinária Hiperativa/tratamento farmacológico , Acetamidas , Animais , Proteínas de Bactérias/sangue , Proteínas de Bactérias/farmacocinética , Modelos Animais de Doenças , Feminino , Cobaias , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição/sangue , Fatores de Transcrição/farmacocinética , Resultado do Tratamento , Triazinas , Bexiga Urinária Hiperativa/sangue , Bexiga Urinária Hiperativa/fisiopatologia
3.
Euro Surveill ; 17(33)2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22913977

RESUMO

We describe polyclonal spread of colistin-resistant Klebsiella pneumoniae in an acute general hospital in Italy. Between June and December 2011, 58 colistin-resistant K. pneumoniae isolates were recovered from 28 patients admitted to different wards, but mainly in the intensive care units. All isolates were tested for drug susceptibility and the presence of beta-lactamase (bla) genes. Clonality was investigated by repetitive extragenic palindromic (rep)-PCR and multilocus sequence typing (MLST). Fifty-two isolates had minimum inhibitory concentrations (MICs) for colistin of 6-128 mg/L, carried bla(KPC3) and were attributed to sequence type ST258. The remaining six isolates were susceptible to carbapenems, exhibited MICs for colistin of 3-32 mg/L, and belonged to two different types, ST15 and ST273. Rep-PCR included all isolates in three clusters, one containing all ST258 KPC-3-producing isolates and two containing ST15 and ST273 isolates.Cross-transmission containment measures and intensification of staff and environmental hygiene could not stop the outbreak. Selective pressure and horizontal transmission probably contributed to emergence and spread of three different strains of colistin-resistant K. pneumoniae in the hospital. Strict implementation of the above measures and a wider awareness of the antimicrobial resistance threat are crucial to preserve the last therapeutic options of the multidrug-resistant Gram-negative infections.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla , Hospitais Gerais , Humanos , Unidades de Terapia Intensiva , Itália/epidemiologia , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/enzimologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Quartos de Pacientes , Reação em Cadeia da Polimerase , beta-Lactamases/biossíntese , beta-Lactamases/genética
4.
Minerva Pediatr ; 63(1): 73-78, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21311432

RESUMO

Subacute sclerosing panencephalitis (SSPE) is a progressive neurological disorder of childhood and early adolescence caused by persistent defective measles virus. Clinical manifestations appear many years after the acute measles infection. The incidence of SSPE has substantially declined after the introduction of an effective vaccine. We report a case of a child with SSPE that began with atonia, dysarthria, and intellectual deterioration without the presence of any particular EEG anomalies. We have reported this girl who was affected by this severe affliction in the hope that, because of the rarity of SSPE, it would not go undiagnosed.


Assuntos
Sarampo/complicações , Panencefalite Esclerosante Subaguda/diagnóstico , Antivirais/uso terapêutico , Criança , Progressão da Doença , Quimioterapia Combinada , Disartria , Eletroencefalografia , Feminino , Humanos , Inosina Pranobex/uso terapêutico , Interferon beta/uso terapêutico , Vacina contra Sarampo/efeitos adversos , Prognóstico , Índice de Gravidade de Doença , Panencefalite Esclerosante Subaguda/imunologia , Panencefalite Esclerosante Subaguda/terapia
5.
Neuroreport ; 11(10): 2271-6, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-10923684

RESUMO

Recent evidence suggests that the activation of the Jun N-terminal kinase (JNK) signal transduction pathway may be important in neuronal responses to stresses such as trophic factor deprivation. Preventing the activation of JNK and expression of c-Jun may, therefore, be neuroprotective. Here, we report that the small molecule CEP-1347, which has been shown to inhibit the JNK signalling pathway, promotes cholinergic activity in cultured embryonic septal neurones. In vivo, we have shown that CEP-1347, administered either by sub-cutaneous (s.c.) injection or by continuous infusion, is partially neuroprotective, for cholinergic neurones in the medial septum, following fimbria-fornix transection. These data suggest that small molecules such as CEP-1347 may have beneficial effects in treating neurodegenerative diseases.


Assuntos
Carbazóis/farmacologia , Colina O-Acetiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Fórnice/fisiologia , Indóis/farmacologia , Neurônios/efeitos dos fármacos , Septo do Cérebro/citologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Mamíferos , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/citologia , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Septo do Cérebro/fisiologia , Transdução de Sinais
6.
J Neurochem ; 75(3): 1200-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10936203

RESUMO

The neuropathology of Parkinson's disease is reflected in experimental animals treated with the selective nigrostriatal dopaminergic neurotoxin MPTP. Neurons exposed to MPTP (MPP(+)) express morphological features of apoptosis, although the intracellular pathways that produce this morphology have not been established. The c-Jun NH(2)-terminal kinase (JNK) signaling cascade has been implicated as a mediator of MPTP-induced apoptotic neuronal death based on the ability of CEP-1347/KT-7515, an inhibitor of JNK activation, to attenuate MPTP-induced nigrostriatal dopaminergic degeneration. In these studies, MPTP-mediated activation of the JNK signaling pathway was assessed in the nigrostriatal system of MPTP-treated mice. MPTP elevated levels of phosphorylated JNK and JNK kinase (MKK4; also known as SEK1 or JNKK), by 2.5- and fivefold, respectively. Peak elevations occurred soon after administration of MPTP and coincided with peak CNS levels of MPP(+). Increased MKK4 phosphorylation, but not JNK phosphorylation, was found in the striatum, suggesting that activation of MKK4 occurs in injured dopaminergic terminals. Both JNK and MKK4 phosphorylations were attenuated by pretreatment with l-deprenyl, indicating that these phosphorylation events were mediated by MPP(+). Moreover, CEP-1347/KT-7515 inhibited MPTP-mediated MKK4 and JNK signaling at a dose that attenuates MPTP-induced dopaminergic loss. These data implicate this signaling pathway in MPTP-mediated nigrostriatal dopaminergic death and suggest that it may be activated in the degenerative process in Parkinson's disease.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Corpo Estriado/fisiologia , MAP Quinase Quinase 4 , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/fisiologia , Substância Negra/fisiologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacocinética , Animais , Carbazóis/farmacologia , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Indóis/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Fosforilação , Selegilina/farmacologia , Transdução de Sinais
7.
J Pharmacol Exp Ther ; 288(2): 421-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9918541

RESUMO

We have identified a bis-ethylthiomethyl analog of K-252a, CEP-1347/KT-7515, that promotes neuronal survival in culture and in vivo. The neuronal survival properties of CEP-1347/KT-7515 may be related to its ability to inhibit the activation of c-jun N-terminal kinase, a key kinase in some forms of stress-induced neuronal death and perhaps apoptosis. There is evidence that the selective nigrostriatal dopaminergic neurotoxin, MPTP, produces neuronal apoptosis in culture and in adult mice. Thus, our studies were designed to determine if CEP-1347/KT-7515 could protect dopaminergic neurons from MPTP-mediated neurotoxicity. CEP-1347/KT-7515 was assessed for neuroprotective activity in a low dose MPTP model (20 mg/kg) where there was a 50% loss of striatal dopaminergic terminals in the absence of substantia nigra neuronal loss, and a high dose (40 mg/kg) MPTP model where there was a complete loss of dopaminergic terminals and 80% loss of dopaminergic cell bodies. In the low dose MPTP model, CEP-1347/KT-7515 (0.3 mg/kg/day) attenuated the MPTP-mediated loss of striatal dopaminergic terminals by 50%. In the high dose model, CEP-1347/KT-7515 ameliorated the loss of dopaminergic cell bodies by 50% and partially preserved striatal dopaminergic terminals. CEP-1347/KT-7515 did not inhibit monoamine oxidase B or the dopamine transporter, suggesting that the neuroprotective effects of CEP-1347/KT-7515 occur downstream of the metabolic conversion of MPTP to MPP+ and accumulation of MPP+ into dopaminergic neurons. These data implicate a c-jun N-terminal kinase signaling system in MPTP-mediated dopaminergic degeneration and suggest that CEP-1347/KT-7515 may have potential as a treatment for Parkinson's disease.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Carbazóis/uso terapêutico , Dopaminérgicos/toxicidade , Dopamina/fisiologia , Inibidores Enzimáticos/uso terapêutico , Indóis/uso terapêutico , Intoxicação por MPTP , Proteínas Quinases Ativadas por Mitógeno , Degeneração Neural/prevenção & controle , Neurônios/efeitos dos fármacos , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Dopamina/metabolismo , Inibidores da Captação de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monoaminoxidase/efeitos dos fármacos , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Degeneração Neural/induzido quimicamente , Degeneração Neural/enzimologia , Neurônios/enzimologia , Neurônios/patologia , Transdução de Sinais/efeitos dos fármacos , Substância Negra/enzimologia , Tirosina 3-Mono-Oxigenase/metabolismo
8.
Neuroscience ; 86(2): 461-72, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9881861

RESUMO

We have identified a class of small organic molecules, derived from the indolocarbazole K-252a, that promote the survival of cultured neurons. However, many of these indolocarbazoles inhibit protein kinase C and neurotrophin-activated tyrosine kinase receptors. These kinase inhibitory activities may limit the utility of these compounds for neurological disorders. A bis-ethyl-thiomethyl analogue of K-252a, CEP-1347/KT-7515, has been identified that lacks protein kinase C and tyrosine kinase receptor inhibitory activities, yet retains the ability to promote survival of cultured neurons, including cholinergic neurons derived from the basal forebrain. In the present studies, CEP-1347/KT-7515 was assessed for neurotrophic activity on basal forebrain neurons of in vivo rats following excitotoxic insult. Ibotenate infusion into the nucleus basalis magnocellularis reduced levels of choline acetyltransferase activity in the cortex, as well as reduced numbers of choline acetyltransferase-immunoreactive and retrogradely (FluoroGold)-labelled cortically-projecting neurons in the nucleus basalis. Systemically administered CEP-1347/KT-7515 attenuated the loss of cortical choline acetyltransferase activity and the loss of the number of choline acetyltransferase-immunoreactive and retrogradely-labelled FluoroGold neurons in the nucleus basalis. Moreover, CEP-1347/KT-7515 ameliorated the loss of cortical choline acetyltransferase if administration was initiated one day, but not seven days post-lesion. Together, these results demonstrate that CEP-1347/KT-7515 protects damaged cortically-projecting basal forebrain neurons from degeneration. Thus, CEP-1347/KT-7515 may have therapeutic potential in neurodegenerative diseases, such as Alzheimer's disease, in which basal forebrain cholinergic neurons degenerate.


Assuntos
Carbazóis/farmacologia , Colina O-Acetiltransferase/metabolismo , Indóis/farmacologia , Neurônios/fisiologia , Estilbamidinas , Substância Inominada/fisiologia , Animais , Transporte Axonal/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/enzimologia , Lobo Frontal/fisiologia , Lateralidade Funcional , Ácido Ibotênico/toxicidade , Masculino , Neurônios/citologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Substância Inominada/efeitos dos fármacos , Substância Inominada/patologia
9.
J Neurosci ; 15(3 Pt 2): 2280-6, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7891166

RESUMO

NGF found in the basal forebrain is believed to be localized to NGF-dependent cholinergic neurons and derived via retrograde axonal transport from NGF-synthesizing target hippocampal and cortical neurons. The basis for this concept of target-derived NGF is the detection of only limited amounts of NGF mRNA in the basal forebrain, despite relatively high NGF levels there. Our work, using a more sensitive and quantitative RNase protection method for detecting relative NGF mRNA levels, suggested, instead, relatively high levels of NGF mRNA synthesis in the septal region of the basal forebrain (BF-S), a region which contained primarily cells that project to the hippocampus. Similar results were obtained in analyses of a larger portion of the basal forebrain, designated "BF," that encompassed cholinergic neurons that project to both the hippocampus and the cortex. The level of NGF mRNA measured in both BF-S and BF was equivalent to approximately 50% of the amount observed in the hippocampus. Furthermore, relative NGF mRNA levels detected in the BF-S, cortex, and hippocampus were shown to be proportional to NGF protein levels quantitated in each region. The detection of relatively high amounts of NGF synthesis in the BF-S was supported in studies demonstrating rapid NGF receptor (Trk) activation in the basal forebrain by exogenous NGF and in experiments showing that NGF mRNA was inducible in the BF-S by 1,25 dihydroxyvitamin D3. The extent of NGF mRNA induction was similar (approximately twofold) in the BF-S, hippocampus, and cortex, suggesting similar regulatory mechanisms.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fatores de Crescimento Neural/biossíntese , Fatores de Crescimento Neural/farmacologia , Septo Pelúcido/metabolismo , Animais , Calcitriol/farmacologia , Catecóis/farmacologia , Dexametasona/farmacologia , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Interleucina-1/farmacologia , Masculino , Lobo Parietal/efeitos dos fármacos , Lobo Parietal/metabolismo , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/fisiologia , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Receptores Proteína Tirosina Quinases/efeitos dos fármacos , Receptores Proteína Tirosina Quinases/fisiologia , Receptor trkA , Receptores de Fator de Crescimento Neural/efeitos dos fármacos , Receptores de Fator de Crescimento Neural/fisiologia , Septo Pelúcido/efeitos dos fármacos
10.
Mol Pharmacol ; 45(3): 395-401, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8145726

RESUMO

Nerve growth factor (NGF) maintains cholinergic neurons in various animals models of neurodegeneration and is thus a potential treatment for certain neurodegenerative disorders such as Alzheimer's disease. Because NGF does not cross the blood-brain barrier, we have proposed elevating endogenous levels of NGF in the central nervous system with small molecules that induce NGF expression, as an alternative strategy. The present studies were conducted to determine whether pharmacologically elevated levels of NGF are sufficient to cause subsequent stimulation of its high affinity receptor, as measured by increased levels of Trk phosphorylation. Dexamethasone (0.5-20 mg/kg, intraperitoneally) caused a time- and dose-dependent increase in NGF mRNA and NGF protein in the hippocampus and septum of adult male Sprague-Dawley rats. Exogenously administered NGF (1 microgram, intracerebroventricularly) led to a rapid (30 min) and transient increase in Trk phosphorylation in the septum, which has high levels of NGF-specific TrkA. Similarly, dexamethasone led to an increase in Trk phosphorylation only within the septum. Dexamethasone-mediated Trk phosphorylation was dose and time dependent, with peak increases being observed 12 hr after injection, concurrently with peak increases in NGF protein. These data demonstrate an increase in activation of the high affinity NGF receptor with a compound that elevates levels of NGF in the central nervous system, and they support the strategy of discovering a pharmacological agent that induces NGF as a method for treating neurodegenerative disorders.


Assuntos
Dexametasona/farmacologia , Fatores de Crescimento Neural/biossíntese , Proteínas Oncogênicas/metabolismo , Animais , Relação Dose-Resposta a Droga , Masculino , Fatores de Crescimento Neural/genética , Fosforilação/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
11.
Brain Res ; 633(1-2): 189-96, 1994 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-8137156

RESUMO

We have proposed that elevating levels of nerve growth factor (NGF) in the CNS is a rational strategy for treating certain neurodegenerative disorders. The present studies were conducted to determine: (1) if pharmacologically induced levels of NGF could be sustained for an extended time, and (2) if correlations exist between increases in NGF mRNA and NGF protein in L929 cells and in vivo. Short-term treatment of L929 cells with 1,25-dihydroxyvitamin D3 resulted in a two-fold increase in both NGF mRNA and NGF protein. These increases were sustained for up to 48 h with continuous exposure to 1,25-dihydroxyvitamin D3. In rats, 1,25-dihydroxyvitamin D3 (2.5 nmol; i.c.v.) induced NGF mRNA transiently, with peak two-fold increases observed 4 h post-injection. In contrast to L929 cells, 1,25-dihydroxyvitamin D3 did not elicit an increase in NGF protein after a single administration in vivo. However, consistent with long-term exposure in L929 cells, chronic 6 day infusion of 1,25-dihydroxyvitamin D3 resulted in induction of both NGF mRNA and NGF protein in the brain. These results indicate that 1,25-dihydroxyvitamin D3-mediated NGF induction in cultured L929 cells may predict of NGF induction in vivo, suggesting that L929 cells may have utility in studying underlying mechanisms of NGF induction by 1,25-dihydroxyvitamin D3. On the basis of NGF's ability to increase cholinergic function in animal models of cholinergic degeneration, these results are supportive of a role for NGF inducers as potential drugs for neurodegenerative disorders.


Assuntos
Química Encefálica/efeitos dos fármacos , Calcitriol/farmacologia , Fatores de Crescimento Neural/biossíntese , Proteínas do Tecido Nervoso/biossíntese , RNA Mensageiro/biossíntese , Animais , Peso Corporal/efeitos dos fármacos , Sondas de DNA , Ensaio de Imunoadsorção Enzimática , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Masculino , Camundongos , Fatores de Crescimento Neural/análise , Ratos , Ratos Sprague-Dawley , Estimulação Química
12.
Exp Neurol ; 123(2): 295-302, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8405292

RESUMO

Three structurally unrelated compounds, all of which induce nerve growth factor (NGF) in cell culture systems, were assessed for their ability to induce NGF mRNA in adult rat brain using a highly sensitive RNAse protection assay. Interleukin-1 beta (0.5-1 pmol) and 1,25-dihydroxyvitamin D3 (25-25,000 pmol) were extremely potent inducers of NGF mRNA, being respectively at least 50,000 and 4000 times more potent than 4-methylcatechol. These compounds elicited an approximate twofold increase in NGF mRNA in both the hippocampus and cortex, without altering beta-actin mRNA levels after a single intracerebroventricular injection. The duration of NGF induction was dependent on the compound administered. For example, the elevation of NGF mRNA elicited by interleukin-1 beta peaked at 8 h and lasted for at least 24 h. In contrast, the induction of NGF after 1,25-dihydroxyvitamin D3 and 4-methylcatechol administration peaked between 4 and 8 h and was not apparent 24 h after injection. These results demonstrate induction of NGF mRNA in vivo by administration of physiological or pharmacological agents and differentiate these agents by potency and duration of action. Further, these findings indicate that pharmacological induction of NGF may be a viable strategy for the treatment of neurodegenerative disorders such as Alzheimer's disease.


Assuntos
Encéfalo/metabolismo , Calcitriol/farmacologia , Catecóis/farmacologia , Interleucina-1/farmacologia , Fatores de Crescimento Neural/genética , RNA Mensageiro/metabolismo , Animais , Masculino , RNA Mensageiro/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
14.
J Pharmacol Exp Ther ; 260(3): 1400-9, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1312170

RESUMO

Several analogs of 1-methyl-4-phenylpyridinium (MPP+) were evaluated for their affinity for the dopamine uptake system and their ability to inhibit NADH dehydrogenase (complex I) of the mitochondrial electron-transport chain. Moreover, these compounds were tested for their ability to cause selective dopaminergic neurotoxicity in cultured mesencephalic neurons. Simultaneous [3H]dopamine and gamma-amino-[14C]butyric acid uptake and immunocytochemical techniques were used as indices of neuronal damage in cultured cells. The compounds that were potent and selective dopaminergic neurotoxins had high affinity for the dopamine transport system, as measured by their ability to cause dopamine release, and were similar to MPP+ in inhibiting mitochondrial respiration. One compound (1-methyl-4-phenylpyrimidinium) had high affinity for the dopamine uptake system but was a weak inhibitor of mitochondrial respiration and, accordingly, was not neurotoxic. The 4'-alkylated analogs of MPP+, which were poor substrates for the dopamine uptake system and extremely potent inhibitors of mitochondrial respiration, caused a nonselective damage of neurons in culture. Analogs that were not substrates for the dopamine carrier and not inhibitors of mitochondrial respiration were not neurotoxic. This study describes the neurotoxicity of a number of analogs of MPP+ and highlights the importance of the dopamine uptake system and the ability to inhibit mitochondrial respiration as critical processes in conferring selectivity and neurotoxicity, respectively, to MPP+ and analogs, for dopaminergic neurons in culture.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Dopamina/metabolismo , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Receptores Dopaminérgicos/efeitos dos fármacos , 1-Metil-4-fenilpiridínio/análogos & derivados , Animais , Células Cultivadas , Dose Letal Mediana , Mitocôndrias/metabolismo , Ratos , Receptores de GABA-A/efeitos dos fármacos , Relação Estrutura-Atividade
15.
J Neurochem ; 58(3): 1052-9, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1737983

RESUMO

The effects of 1-methyl-4-(2'-ethylphenyl)-1,2,3,6-tetrahydropyridine (2'Et-MPTP), 1-methyl-4-(2'-ethylphenyl)pyridinium (2'Et-MPP+), and the classic complex 1 inhibitor, rotenone, on toxicity as well as on rates of glucose use and lactate production were studied using the pheochromocytoma PC12 cell line. PC12 cells are neoplastic in nature and have a high rate of glycolysis accompanied by a large production of lactate and a low use of glucose carbon through the Krebs cycle. 1-Methyl-4-phenylpyridinium (MPP+) and analogues such as 2'Et-MPP+ are actively accumulated by mitochondrial preparations in vitro and block NADH dehydrogenase of complex 1. This blockade results in biochemical sequelae that are ultimately cytotoxic. In this study, untreated PC12 cells used glucose and concomitantly accumulated lactate in a time-dependent manner at all concentrations of glucose studied. Treatment with 50 microM 2'Et-MPP+ or 50 nM rotenone increased both rates significantly, indicating a shift toward increased glycolysis. Cell death caused by the neurotoxins was also time and concentration dependent and markedly enhanced by glucose depletion in the medium. The increase in 2'Et-MPTP-induced toxicity in low glucose-supplemented cells was not due to an increase in pyridinium formation from the tetrahydropyridine, but rather to the lack of glucose for glycolysis. Moreover, inhibition of glycolysis with 2-deoxyglucose or iodoacetic acid also enhanced the lethality of the neurotoxins to the cells. The data in this study provide additional support to the hypothesis that 2'Et-MPP+ or related analogues act to kill cells by inhibiting mitochondrial respiration.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/análogos & derivados , Glicólise/efeitos dos fármacos , Células PC12/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , 1-Metil-4-fenilpiridínio/farmacologia , Animais , Glucose/metabolismo , Lactatos/metabolismo , Ácido Láctico , Células PC12/metabolismo , Rotenona/farmacologia , Fatores de Tempo
16.
Life Sci ; 45(1): 15-23, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2545989

RESUMO

We investigated the activity of bombesin (BN), neuromedin-C (NM-C) and neuromedin-B (NM-B) on serotonin (5-HT) release and reuptake in rat hypothalamus (HYP) in vitro. BN and NM-C but not NM-B (all 1 microM) decreased K+ evoked 3H-5-HT release from superfused HYP slices by 25%. Bacitracin (BCN, 2 micrograms/ml), a nonspecific peptidase inhibitor, reversed the inhibitory effect of BN on K+ evoked 3H-5-HT release. Phosphoramidon (PAN, 10 microM) an endopeptidase 24.11 inhibitor, abolished the inhibitory effect of BN, but not NM-C, on K+ evoked 3H-5-HT release. The peptidyl dipeptidase A inhibitor enalaprilat (ENP, 10 microM), enhanced both BN and NM-C inhibition of 3H-5-HT release. Bestatin (BST, 10 microM) had no effect on BN or NM-C inhibitory activity on 3H-5-HT release. Neither BN, NM-C nor NM-B affected reuptake of 3H-5-HT into HYP synaptosomes alone or in combination with any of the peptidase inhibitors, nor did these peptides alter the ability of fluoxetine to inhibit 3H-5-HT uptake. These data suggest: a) that BN-like peptides may alter neurotransmission in the HYP by acting presynaptically on the 5-HT release mechanism; b) a similarity in the structural requirements for the BN induced inhibition of 5-HT release and BN evoked thermoregulatory disturbances; and c) that peptidases may selectively augment or reduce pharmacologic activity of BN-like peptides upon CNS administration.


Assuntos
Bombesina/farmacologia , Hipotálamo/metabolismo , Neurocinina B/análogos & derivados , Fragmentos de Peptídeos/farmacologia , Serotonina/metabolismo , Sequência de Aminoácidos , Aminopeptidases/antagonistas & inibidores , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Bacitracina/farmacologia , Interações Medicamentosas , Enalapril/análogos & derivados , Enalapril/farmacologia , Enalaprilato , Glicopeptídeos/farmacologia , Hipotálamo/efeitos dos fármacos , Leucina/análogos & derivados , Leucina/farmacologia , Masculino , Dados de Sequência Molecular , Neurocinina B/farmacologia , Inibidores de Proteases/farmacologia , Ratos , Ratos Endogâmicos
17.
J Am Coll Cardiol ; 10(1): 73-80, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3597997

RESUMO

The onset of bundle branch block during acute myocardial infarction is indicative of ischemia in the distribution of the left anterior descending coronary artery. However, whether patients with chronic coronary artery disease and bundle branch block have a predominance of left anterior descending artery lesions is not known. Similarly, the prognostic implications of bundle branch block have been studied primarily in the setting of acute myocardial infarction, and the independent prognostic implications of bundle branch block in patients with chronic coronary artery disease are not known. The electrocardiograms (ECGs) of 15,609 patients with chronic coronary artery disease who underwent coronary and left ventricular angiography as part of the Coronary Artery Surgery Study (CASS) were reviewed, and 522 patients with bundle branch block were identified. Patients with bundle branch block had both more extensive coronary artery disease and worse left ventricular function than did patients without bundle branch block. However, no particular location of coronary artery stenosis or left ventricular wall motion abnormality predominated in patients with bundle branch block. During a follow-up period of 4.9 +/- 1.3 years, 2,386 patients died. Actuarial probability of mortality at 2 years in patients with left bundle branch block was more than five times that in patients without bundle branch block (p less than 0.0001), and in patients with right bundle branch block the mortality rate was approximately twice that in patients without bundle branch block (p less than 0.0001). Stepwise Cox regression analysis showed that left bundle branch block, but not right bundle branch block, was a strong predictor of mortality, independent of degree of heart failure, extent of coronary disease and other variables (p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angiografia , Bloqueio de Ramo/complicações , Doença das Coronárias/complicações , Bloqueio de Ramo/diagnóstico por imagem , Bloqueio de Ramo/mortalidade , Doença Crônica , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/mortalidade , Coração/fisiopatologia , Insuficiência Cardíaca/complicações , Ventrículos do Coração , Humanos , Prognóstico
18.
Biol Neonate ; 47(1): 1-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3967053

RESUMO

This study was performed to determine whether covering the eyes with an opaque screen over the head end of the bassinet instead of the normal patch would improve the behavioral organization of jaundiced, but otherwise healthy, term infants treated with phototherapy. 38 matched infants were randomly assigned to have a patch or a screen. Serum bilirubin at the time of observation was 11.2-17.5 mg/100 ml (mean = 13.7, patch) and 9.4-16.4 mg/100 ml (mean = 13.4, screen). 19 infants, of whom 11 were jaundiced (6.2-14.3 mg/100 ml, mean = 10.3), served as control subjects. The infants were examined with the Brazelton scale on the 3rd day after birth, when the patch subjects had been under blue light from 6 to 45 h (mean = 23.9), and the screen subjects from 6 to 61.5 h (mean = 22.6). The control subjects scored better (all differences, p less than 0.05) than the patch subjects on inanimate visual, animate visual, visual and auditory, alertness. The control subjects also did better than the screen subjects on inanimate visual, animate visual, animate auditory, visual and auditory, alertness, but poorer on motor maturity and consolability. The screen subjects did poorer than the patch subjects only on skin color lability. At 1 month of age, 9 sets of matched infants were examined. The only difference was that the control subjects did better than the patch subjects on animate visual and lability of state. Our data confirm the poorer short-term orientation performance of jaundiced infants treated with phototherapy but do not indicate that covering the eyes with an opaque screen improves behavioral organization.


Assuntos
Comportamento Infantil , Dispositivos de Proteção dos Olhos , Icterícia Neonatal/terapia , Fototerapia , Equipamentos de Proteção , Feminino , Humanos , Recém-Nascido , Masculino , Privação Sensorial , Visão Ocular
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