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1.
Laryngorhinootologie ; 94(3): 163-8, 2015 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-25089633

RESUMO

BACKGROUND: A validated instrument to measure patient-related outcome and quality of life in facial palsy is not available in German language. METHODS: 2 appropriate questionnaires, the Facial Clinimetric Evaluation (FaCE) scale and the Facial Disability Index (FDI) were translated and validated according to international guidelines. The internal consistency of both German versions was assessed. The results of FaCE and FDI were correlated with results of the SF-36, the House-Brackmann scale and the Stennert index. RESULTS: 122 facial palsy patients with a median duration of 4.7 months were included. FaCE and FDI showed good to very good psychometric characteristics with Cronbach's alpha values between 0.667 and 0.907. Both questionnaires were able to distinguish different degrees of facial palsy. The comparison to the SF-36 shows the highest correlation with the subscale social function. DISCUSSION: The German versions of the FDI and FaCE are valid and should now be applied more frequently to assess the disease-specific quality of life in patients with facial palsy.


Assuntos
Comparação Transcultural , Avaliação da Deficiência , Paralisia Facial/diagnóstico , Paralisia Facial/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários , Adulto , Idoso , Paralisia Facial/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes , Fatores de Risco , Ajustamento Social , Tradução
2.
Nervenarzt ; 83(8): 988-93, 2012 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-22814634

RESUMO

In the last 25 years deep brain stimulation (DBS) has increased the therapeutic options as well as the pathophysiological understanding of movement disorders (MDS) to an unforeseen extent. This paper covers the state of the art of DBS treatment of Parkinson's disease, tremors, dystonia and other rare forms of MDS and gives an short overview of the mechanisms of action of DBS.


Assuntos
Encefalopatias/prevenção & controle , Encefalopatias/reabilitação , Estimulação Encefálica Profunda/métodos , Estimulação Encefálica Profunda/tendências , Transtornos dos Movimentos/prevenção & controle , Transtornos dos Movimentos/reabilitação , Encefalopatias/complicações , Humanos , Transtornos dos Movimentos/etiologia
3.
Acta Neurochir (Wien) ; 151(7): 751-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19468677

RESUMO

UNLABELLED: Deep brain stimulation (DBS) of the internal globus pallidus (Gpi) is an effective therapy for various types of dystonia. The authors describe their technical approach for securing appropriate placement of the stimulating electrodes within the Gpi under general anaesthesia, including MRI based individualised anatomical targeting combined with electrophysiological mapping of the Gpi using micro-recording (MER) as well as macrostimulation and report the subsequent clinical outcome and complications using this method. METHOD: We studied 42 patients (male-female ratio 25:17; mean age 43.6 years, range 9 to 74 years) consecutively operated at the Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Kiel, between 2001 - 2006. One patient underwent unilateral implantation after a right-sided pallidotomy 30 years before and strictly unilateral symptoms; all other implantations were bilateral. Two patients had repeat surgery after temporary removal of uni- or bilateral implants secondary to infection. Overall, 86 DBS electrodes were implanted. In 97% of the implantations, at least three microelectrodes were inserted simultaneously for MER and test stimulation. Initial anatomical targeting was based on stereotactic atlas coordinates and individual adaptation by direct visualisation of the Gpi on the stereotactic T2 or inversion-recovery MR images. The permanent electrode was placed according to the results of MER and test stimulations for adverse effects. FINDINGS: The average improvement from baseline in clinical ratings using either the Burke-Fahn-Marsden-Dystonia (BFMDRS) or Toronto-Western-Spasmodic-Torticollis (TWSTR) rating scale at the last post-operative follow-up (mean 16.4 ; range 3-48 months) was 64.72% (range 20.39 to 98.52%). The post-operative MRI showed asymptomatic infarctions of the corpus caudatus in three patients and asymptomatic small haemorrhages in the lateral basal ganglia in two patients. One patient died due to a recurrent haemorrhage which occurred three months after the operation. The electrodes were implanted as follows: central trajectory in 64%, medial trajectory in 20%, anterior in 9% and lateral dorsal trajectories in 3.5% each. The reduction in BFMDRS or TWSTR motor score did not differ between the group implanted in the anatomically defined (central) trajectory bilateral (-64.15%, SD 23.8) and the physiologically adopted target (uni- or bilateral) (-63.39%, SD 23.1) indicating that in both groups equally effective positions were chosen within Gpi for chronic stimulation (t-test, p > 0.4). CONCLUSIONS: The described technique using stereotactic MRI for planning of the trajectory and direct visualisation of the target, intra-operative MER for delineating the boundaries of the target and macrostimulation for probing the distance to the internal capsule by identifying the threshold for stimulation induced tetanic contractions is effective in DBS electrode implantation in patients with dystonia operated under general anaesthesia. The central trajectory was chosen in only 64%, despite individual adaptation of the target due to direct visualisation of the Gpi in inversion recovery MRI in 43% of the patients, demonstrating the necessity of combining anatomical with neurophysiological information.


Assuntos
Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/métodos , Distúrbios Distônicos/terapia , Globo Pálido/anatomia & histologia , Globo Pálido/cirurgia , Neuronavegação/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral/métodos , Anestésicos Gerais/farmacologia , Mapeamento Encefálico/instrumentação , Mapeamento Encefálico/métodos , Criança , Distúrbios Distônicos/fisiopatologia , Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Feminino , Globo Pálido/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Microeletrodos/normas , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Monitorização Intraoperatória/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
4.
J Neurophysiol ; 100(5): 2515-24, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18701754

RESUMO

We recorded resting-state neuronal activity from the human subthalamic nucleus (STN) during functional stereotactic surgeries. By inserting up to five parallel microelectrodes for single- or multiunit recordings and applying statistical spike-sorting methods, we were able to isolate a total of 351 single units in 65 patients with Parkinson's disease (PD) and 33 single units in 9 patients suffering from essential tremor (ET). Among these were 93 pairs of simultaneously recorded neurons in PD and 17 in ET, which were detected either by the same (n = 30) or neighboring microelectrodes (n = 80). Essential tremor is a movement disorder without any known basal ganglia pathology and with normal dopaminergic brain function. By comparing the neuronal activity of the STN in patients suffering from PD and ET we intended to characterize, for the first time, changes of basal ganglia activity in the human disease state that had previously been described in animal models of Parkinson's disease. We found a significant increase in the mean firing rate of STN neurons in PD and a relatively larger fraction of neurons exhibiting burstlike activity compared with ET. The overall proportion of neurons exhibiting intrinsic oscillations or interneuronal synchronization as defined by significant spectral peaks in the auto- or cross-correlations functions did not differ between PD and ET when considering the entire frequency range of 1-100 Hz. The distribution of significant oscillations across the theta (1-8 Hz), alpha (8-12 Hz), beta (12-35 Hz), and gamma band (>35 Hz), however, was uneven in ET and PD, as indicated by a trend in Fisher's exact test (P = 0.05). Oscillations and pairwise synchronizations within the 12- to 35-Hz band were a unique feature of PD. Our results confirm the predictions of the rate model of Parkinson's disease. In addition, they emphasize abnormalities in the patterning and dynamics of neuronal discharges in the parkinsonian STN, which support current concepts of abnormal motor loop oscillations in Parkinson's disease.


Assuntos
Potenciais de Ação/fisiologia , Neurônios/fisiologia , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/fisiopatologia , Núcleo Subtalâmico/patologia , Análise de Variância , Distribuição de Qui-Quadrado , Tremor Essencial/patologia , Tremor Essencial/fisiopatologia , Humanos , Periodicidade
5.
Neurology ; 70(16 Pt 2): 1445-51, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18413569

RESUMO

BACKGROUND: Axial symptoms of Parkinson disease (PD) may result from dysfunctional basal ganglia-brainstem connections. In this study, we assessed whether modulation of basal ganglia activity by high-frequency stimulation of the subthalamic nucleus (STN-HFS) in PD had an impact on the brainstem-controlled startle system. METHODS: We assessed auditory startle responses (recorded from right orbicularis oculi, masseter, sternocleidomastoid, biceps brachii, and soleus muscle) and audiospinal facilitation (startle conditioned soleus H-reflexes at interstimulus intervals of 0-250 msec) in 24 patients with PD with chronically implanted, bilateral STN electrodes in the stimulation on (STIM ON) and off condition (STIM OFF) and 20 healthy controls. RESULTS: The mixed linear analysis of variance model revealed a significant effect for the startle onset latency in the orbicularis oculi muscle for the factors GROUP (patients with PD vs controls; p < 0.0001, F = 44.66) and STIM (nested within GROUP) (p = 0.0034, F = 8.79). Audiospinal facilitation was modulated by STN-HFS as shown by highly significant effects for STIM [GROUP] (p < 0.0001, F = 15.9), ISI [GROUP] (p < 0.0001, F = 3.5), and the interaction of ISI x STIM [GROUP] (p = 0.0085, F = 2.65) in the mixed linear model. CONCLUSION: High-frequency stimulation of the subthalamic nucleus alters the excitability of the brainstem startle system in Parkinson disease, most likely by releasing the reticular motor system from abnormal descending input of the basal ganglia via pallidotegmental pathways.


Assuntos
Estimulação Acústica/métodos , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/fisiopatologia , Reflexo de Sobressalto/fisiologia , Medula Espinal/fisiologia , Núcleo Subtalâmico/fisiologia , Idoso , Estimulação Elétrica/métodos , Feminino , Reflexo H/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia
6.
Zentralbl Neurochir ; 69(2): 71-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18444217

RESUMO

OBJECTIVE: Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective treatment for medically refractory primary dystonia. We present our technique for direct preoperative visualization of the target using a fast spin-echo inversion-recovery (FSE-IR) sequence. METHODS: Twenty-three consecutive patients (mean age 41 years, range 9-68 years, male to female ratio 11:12) with severe dystonia were operated using a combination of FSE-IR imaging for direct visualization of the globus pallidus internus with stereotactic, gadolinium-enhanced T1-MPRage images. The complete procedure, including stereotactic MRI, was performed under general anesthesia with propofol and remifentanyl. We used multichannel microdrive systems (Medtronic; Alpha-Omega) to introduce up to five parallel microelectrodes for microelectrode recordings (MER) and test stimulation with the central trajectory directed at the anatomically predefined target. The initial standard coordinates in relation to the mid-commissural point (mid-AC-PC) were as follows: lateral 21 mm, anterior 3 mm, and inferior 2 mm, which were then adapted to the individual case based on direct visualization of the target area and further refined by the intraoperative neurophysiology. RESULTS: In ten patients (43%) atlas-based standard coordinates were modified based on the direct visualization of the GPi in the FSE-IR images (bilaterally in seven patients, unilaterally in three). The modified targets ranged from 18.5 to 23.5 mm (mean 20.76 mm) laterally, 1-7 mm (mean 2.75 mm) anteriorly and 1-2 mm (mean 1.95 mm) inferiorly to the mid-AC-PC. We implanted the permanent electrode based on the results of MER and intraoperative stimulation performed to determine the threshold for pyramidal tract responses on the central trajectory in 67%, medially in 16%, anteriorly in 11%, laterally in 4%, dorsally in 2%. The procedure resulted in excellent clinical benefits (average reduction of the Burke-Fahn-Marsden Dystonia Rating Score (BFMDRS) or the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) were respectively 65.9%, range 20.9-91.4%) within the first year after surgery. Safety was demonstrated by the absence of intracranial bleeding or other surgical complications causing neurological morbidity. CONCLUSION: Inversion recovery sequences are an excellent tool for direct visualization of the GPi. These images can be fused to stereotactic MRI or CCT and may help to improve anatomical targeting of the GPi for the implantation of DBS electrodes.


Assuntos
Estimulação Encefálica Profunda , Distonia/terapia , Imagem Ecoplanar/métodos , Eletrodos Implantados , Globo Pálido/anatomia & histologia , Globo Pálido/cirurgia , Procedimentos Neurocirúrgicos/métodos , Implantação de Prótese/métodos , Técnicas Estereotáxicas , Adolescente , Adulto , Idoso , Criança , Distonia/genética , Distonia/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Implantação de Prótese/efeitos adversos
7.
Zentralbl Neurochir ; 69(2): 76-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18444218

RESUMO

OBJECTIVE: Deep brain stimulation (DBS) has become a standard procedure for movement disorders such as Parkinson's disease, essential tremor or dystonia. Recently, deep brain stimulation of the posterior hypothalamus has been shown to be effective in the treatment of drug-resistant chronic cluster headache. METHODS: DBS of the posterior inferior hypothalamus was performed on two patients with chronic cluster headaches, one 55-year-old man with medically intractable chronic cluster headache since 1996, and one 31-year-old woman with a chronic form since 2002. Both patients showed continuous worsening headaches in the last years despite high dose medical treatment. The patients fulfilled the published criteria for DBS in chronic cluster headaches. Electrodes were implanted stereotactically in the ipsilateral posterior hypothalamus according to the published coordinates (2 mm lateral, 3 mm posterior, 5 mm inferior) referenced to the mid-AC-PC line. RESULTS: The intra- and postoperative course was uneventful and postoperative MRI control documented regular position of the DBS electrodes. The current stimulation parameters were at 12 months postoperatively 0 neg., G pos.; 5.5 V; 60 micros; 180 Hz (Case 1) and 0 neg., G pos.; 3.0 V; 60 micros; 185 Hz, at 3 months postoperatively (Case 2). Surgery- or stimulation-related side effects were not observed. Both patients showed initial pain reduction in the first days whereas 12 respectively 3 month follow-up did not show a significant reduction in attack frequency or intensity. CONCLUSION: Deep brain stimulation of the posterior inferior hypothalamus is an experimental procedure and should be restricted to selected therapy-refractory patients and should be performed in centers experienced in patient selection and performance of DBS as well as postoperative pain treatment. A prospective multi-centre study is necessary to evaluate its effectiveness.


Assuntos
Cefaleia Histamínica/terapia , Estimulação Encefálica Profunda , Hipotálamo Posterior/fisiologia , Adulto , Doença Crônica , Eletrodos Implantados , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Microeletrodos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Procedimentos Neurocirúrgicos , Medição da Dor , Falha de Tratamento
8.
Mov Disord ; 22(5): 679-84, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17266046

RESUMO

Rarely, the postoperative management of patients with subthalamic deep brain stimulation (STN-DBS) is complicated by pharmacologically intractable dyskinesias. Here we report that in three of these patients additional stimulation of a proximal contact located within the subthalamic white matter may lead to a significant reduction of dyskinesias associated with STN-DBS. We propose that pallidofugal fiber tracts play a major role in the etiopathology of dyskinesias and their blockade through DBS may explain our observations.


Assuntos
Estimulação Encefálica Profunda/métodos , Discinesias/terapia , Fibras Nervosas/fisiologia , Doença de Parkinson/reabilitação , Complicações Pós-Operatórias/terapia , Núcleo Subtalâmico/fisiopatologia , Discinesias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Doença de Parkinson/fisiopatologia , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/fisiopatologia
9.
Neurosci Lett ; 386(3): 156-9, 2005 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-16024174

RESUMO

We present the results of continuous microelectrode recordings from individual pallidal neurons in patients with idiopathic torsion dystonia under different levels of propofol anesthesia. Neither the estimated plasma concentration of propofol nor the level of consciousness had a consistent effect on abnormally low neuronal firing rates. Our data support the pathophysiological model of a decreased basal ganglia output in dystonia and argue against a possible pharmacological artifact.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Distonia Muscular Deformante/fisiopatologia , Globo Pálido/efeitos dos fármacos , Globo Pálido/fisiopatologia , Neurônios/efeitos dos fármacos , Propofol/farmacologia , Potenciais de Ação/fisiologia , Adolescente , Adulto , Anestésicos Intravenosos/sangue , Anestésicos Intravenosos/farmacologia , Artefatos , Estado de Consciência/efeitos dos fármacos , Estado de Consciência/fisiologia , Eletrodiagnóstico/métodos , Eletrofisiologia/métodos , Humanos , Microeletrodos , Pessoa de Meia-Idade , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Neurônios/fisiologia , Propofol/sangue
10.
J Neurosci ; 20(12): 4573-81, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10844027

RESUMO

NMDA receptors interact via the extended intracellular C-terminal domain of the NR2 subunits with constituents of the postsynaptic density for purposes of retention, clustering, and functional regulation at central excitatory synapses. To examine the role of the C-terminal domain of NR2A in the synaptic localization and function of NR2A-containing NMDA receptors in hippocampal Schaffer collateral-CA1 pyramidal cell synapses, we analyzed mice which express NR2A only in its C-terminally truncated form. In CA1 cell somata, the levels, activation, and deactivation kinetics of extrasynaptic NMDA receptor channels were comparable in wild-type and mutant NR2A(Delta)(C/)(Delta)(C) mice. At CA1 cell synapses, however, the truncated receptors were less concentrated than their full-length counterparts, as indicated by immunodetection in cultured neurons, synaptosomes, and postsynaptic densities. In the mutant, the NMDA component of evoked EPSCs was reduced in a developmentally progressing manner and was even more reduced in miniature EPSCs (mEPSCs) elicited by spontaneous glutamate release. Moreover, pharmacologically isolated NMDA currents evoked by synaptic stimulation had longer latencies and displayed slower rise and decay times, even in the presence of an NR2B-specific antagonist. These data strongly suggest that the C-terminal domain of NR2A subunits is important for the precise synaptic arrangement of NMDA receptors.


Assuntos
Hipocampo/fisiologia , Células Piramidais/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Sinapses/fisiologia , Sinaptossomos/fisiologia , Animais , Bicuculina/farmacologia , Células Cultivadas , Dendritos/fisiologia , Embrião de Mamíferos , Potenciais Evocados/efeitos dos fármacos , Potenciais Evocados/fisiologia , Cinética , Magnésio/farmacologia , Camundongos , Células Piramidais/citologia , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Deleção de Sequência , Sinapses/ultraestrutura , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/ultraestrutura
11.
J Subst Abuse Treat ; 16(4): 321-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10349605

RESUMO

Alcohol addiction affects many clients that enter the offices of traditional mental health professionals. Their recovery is impacted by what goes on inside the office, in treatment, as well as by involvement outside the office, in 12-step programs as Alcoholics Anonymous (AA). This article examines alcoholism as a thought disorder and cognitive restructuring as an effective model of treatment. Cognitive restructuring occurs in therapy and in AA. It can, therefore, be the bridge that encourages understanding and cooperation between the two factors influencing recovery.


Assuntos
Transtornos Relacionados ao Uso de Álcool/psicologia , Transtornos Relacionados ao Uso de Álcool/reabilitação , Alcoólicos Anônimos/organização & administração , Transtornos Cognitivos/terapia , Dissonância Cognitiva , Feminino , Humanos , Masculino , Princípios Morais , Avaliação de Programas e Projetos de Saúde , Processos Psicoterapêuticos , Recuperação de Função Fisiológica , Autoimagem
12.
HNO ; 37(9): 389-93, 1989 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-2808015

RESUMO

A combination of midazolam and alfentanil was used on 24 patients for induction of general anaesthesia. Anaesthesia was maintained with N2O/O2 and repeated injections of alfentanil. The mean operation time was 40.8 min. At the end of surgery the patients recovered 4.8 min after antagonisation of the alfentanil with naloxon, and the endotracheal tube could be removed. Thirty, 60 and 120 min after extubation the patients were asked to perform a Marschner's test, which measures the ability to concentrate on fast intellectual work. Up to 660 simple arithmetical additions could be checked within 7.5 min. The intellectual performance recovered quickly: after 30 min 79% of the pre-operative values were reached, after 60 min 85% and after 120 min 90%. Midazolam is suitable as an induction agent for shortlasting otorhinolaryngological surgery.


Assuntos
Anestesia Geral , Nível de Alerta/efeitos dos fármacos , Midazolam , Otorrinolaringopatias/cirurgia , Complicações Pós-Operatórias/diagnóstico , Adolescente , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resolução de Problemas/efeitos dos fármacos
13.
Arch Gen Psychiatry ; 34(1): 51-5, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-836128

RESUMO

Diagnostic rates of routine hospital first and total admissions in various categories of functional mental illness in three strongly Schneider-oriented German psychiatric clinics over 40 years were examined. No matter how centers and categories were compared, statistically significant inconsistency was almost always found. Only first admissions for schizophrenia and mania in Munich and Heidelberg, as well as total schizophrenic admissions in Munich and Homburg/Saar, showed no significant diagnostic differences. However, from a practical point of view, actual percentage differences found in schizophrenia and mania were really not that great; indeed, rather similar diagnostic rates were apparent. This was in contrast to actual large percentage discrepancies shown between Munich on the one hand and Heidelberg and Homburg/Saar on the other with respect to manic-depressive illness and psychotic depression.


Assuntos
Transtornos Mentais/diagnóstico , Transtornos de Adaptação/diagnóstico , Transtorno Bipolar/diagnóstico , Depressão/diagnóstico , Alemanha Ocidental , Humanos , Transtornos Neuróticos/diagnóstico , Transtornos da Personalidade/diagnóstico , Esquizofrenia/diagnóstico
14.
Planta ; 134(3): 295-9, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24419785

RESUMO

Abscisic acid (ABA) in lanolin, applied to the internode of decapitated runner bean plants enhances the outgrowth of lateral buds. The optimum concentration of the paste is 10(-5) M. The effect of ABA is counteracted by indoleacetic acid (IAA) but not by gibberellic acid (GA3). There is no effect when ABA is applied to the apical bud or lateral buds of intact plants. However, 13.2 ng given to the lateral buds of decapitated plants stimulate their growth, whereas higher concentrations are inhibitory. Consequently, ABA enhances growth of lateral buds directly, but only when apical dominance is already weakened. The growth of the decapitated 2(nd) internode was not affected by ABA. Radioactivity from [2-(14)C] ABA, applied to nonelongating 2(nd) internode stumps of decapitated runner bean plants moves to the lateral buds, whereas [1-(14)C]IAA-and [(3)H]GA1-translocation is much weaker. ABA transport is inhibited if IAA or [(3)H]GA1 is applied simultaneously. In elongating internodes [(14)C]ABA is almost completely immobile. [(14)C]IAA-and [(3)H]GA1-translocation is not affected by ABA. The amount of radioactivity from labelled ABA, translocated to the lateral buds, is highest during the early stages of bud outgrowth.

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