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1.
J Mol Evol ; 47(1): 81-92, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9664699

RESUMO

The complete set of available ribosomal proteins was utilized, at both the peptidic and the nucleotidic level, to establish that plants and metazoans form two sister clades relative to fungi. Different phylogenetic inference methods are applied to the sequence data, using archeans as the outgroup. The evolutionary length of the internal branch within the eukaryotic crown trichotomy is demonstrated to be, at most, one-tenth of the evolutionary length of the branch leading to the cenancester of these three kingdoms.


Assuntos
Grupos de População Animal/classificação , Evolução Molecular , Fungos/classificação , Plantas/classificação , Proteínas Ribossômicas/genética , Animais , Simulação por Computador , Modelos Genéticos , Filogenia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
3.
Pharmacology ; 53(2): 79-86, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8902872

RESUMO

Myocardial ischemia-reperfusion alters regional and systemic platelet function. The aim of our study was to elucidate the role of the Mac-1 receptor in changes of platelet function by using the leumedin, NPC-15669, an inhibitor of Mac-1 upregulation. In an open-chest swine model (n = 15), the treatment group (n = 6) received NPC-15669 (10 mg/kg loading dose over 12 min at the rate of 5 ml/min at the onset of left-anterior descending coronary artery occlusion, followed by constant infusion at 6 mg kg-1 h-1 during 90 min of reperfusion). Regional platelet aggregation (response to 5 microM ADP) increased after 15 min occlusion (126% of baseline) and at 90 min of reperfusion (156% of baseline). This increase in platelet aggregability was inhibited by NPC-15669 (83% of baseline after 15 min occlusion and 98% of baseline at 90 min reperfusion, both p < 0.001 compared to control). Systemic platelet function was not affected by NPC-15669 after 15 min occlusion (102% of baseline vs. 96% of baseline for control, p = NS). At 90 min of reperfusion platelet function was increased in controls (131% of baseline) and not affected by NPC-15669 (126% of baseline, p = NS). Myocardial neutrophil accumulation did not differ between the control and treatment groups. Inhibition of Mac-1 upregulation by NPC-15669 attenuates the increased regional platelet aggregability resulting from myocardial ischemia-reperfusion, with a less marked effect on the systemic response. The data suggest that Mac-1 may modulate regional platelet responses induced by ischemia-reperfusion. The increased aggregability of platelets during ischemia and reperfusion and its attenuation by inhibition of Mac-1 may be relevant for future strategies to reduce coronary arterial occlusion by platelet thrombi.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Plaquetas/efeitos dos fármacos , Leucina/análogos & derivados , Antígeno de Macrófago 1/efeitos dos fármacos , Traumatismo por Reperfusão/fisiopatologia , Análise de Variância , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Plaquetas/citologia , Plaquetas/patologia , Doença das Coronárias/tratamento farmacológico , Doença das Coronárias/prevenção & controle , Modelos Animais de Doenças , Leucina/administração & dosagem , Leucina/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Suínos , Regulação para Cima/efeitos dos fármacos
5.
Mol Phylogenet Evol ; 4(3): 257-82, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8845963

RESUMO

We have sequenced the chloroplast gene rps4 of 72 species; the sequence of 6 more species was found in the databanks. The 78 species were chosen so as to be representative of two taxonomic levels: the family, with 39 Poaceae, and the class, with 28 additional monocot species. Eleven dicots and other land plants were used as outgroups to the monocots. The 78 sequences were aligned by eye. Phylogenetic reconstruction was performed using the Wagner parsimony method: our first results were in contradiction with classical systematics, due to a local minimum. We then used the results obtained with the new distance method Anataxis to redraw a new tree and carry on further the parsimony calculations starting from this Anataxis tree. Up to 20,000 most parsimonious trees were thus obtained. The robustness of our results was checked by the bootstrap test and decay analyses. The Anataxis and the strict consensus tree fitted the general features of land plant evolution. Some of our results concerning relationships within the monocots corroborated those obtained with the chloroplast gene rbcL. Both genes raise questions concerning the monocot superorders as defined in a previous classification. This study proves the rps4 gene to be a useful phylogenetic tool within the Poaceae family and the Monocotyledonae order.


Assuntos
Cloroplastos/metabolismo , Genes de Plantas , Modelos Genéticos , Filogenia , Proteínas de Plantas/genética , Plantas/genética , Sequência de Bases , Sequência Consenso , Dados de Sequência Molecular , Ribulose-Bifosfato Carboxilase/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
6.
Surg Neurol ; 41(2): 147-51, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8115953

RESUMO

We report a patient with thalamic pain induced by stereotactic biopsy; therefore, the location of the anatomical lesion causing the syndrome is precisely known. The location of the lesion was confirmed by postoperative magnetic resonance imaging and computed tomography. The metabolic consequences of the anatomic lesion were documented by positron emission tomography using as marker 18F-fluoro-2desoxy-glucose. The anatomic, metabolic, and clinical findings are discussed, as well as the neurophysiologic theories of the mechanisms of the thalamic pain syndrome.


Assuntos
Biópsia/efeitos adversos , Dor Intratável/etiologia , Tálamo/anatomia & histologia , Tálamo/metabolismo , Biópsia/métodos , Tronco Encefálico/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor Intratável/metabolismo , Córtex Somatossensorial/metabolismo , Técnicas Estereotáxicas , Síndrome
7.
J Orofac Pain ; 8(3): 243-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7812221

RESUMO

This study used low-power light microscopy to examine the histologic organization of the lateral pterygoid muscle interface with the temporomandibular joint. The sample included parasagittal sections of 20 intact temporomandibular joints from young adults (mean age 26.2 years) at autopsy. The lateral pterygoid muscle showed no consistent divisions into separate anatomic muscle heads at the insertion. The muscle fibers attached to the pterygoid fovea of the condyle immediately inferior to the articular surface in all cases. Some additional fibers inserted superiorly into the more anterior part of the articular disc in a minority of cases (31%). Fibers inserting into the disc represented only 2.4% to 6% of the total superior-inferior length of the muscle insertion. It is hypothesized that the muscular force exerted by these few fibers inserting into the disc would not be sufficient to displace the disc anteriorly to the condyle. There were two histologic types of insertion of the lateral pterygoid muscle to the condyle. The superior part of the insertion was characterized by an identifiable tendon inserting through fibrocartilage. In the inferior part of the insertion, the muscle attached to periosteum without an obvious tendon. The presence of this tendon must be recognized in interpretation of soft tissue temporomandibular joint imaging.


Assuntos
Músculos Pterigoides/anatomia & histologia , Articulação Temporomandibular/anatomia & histologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Côndilo Mandibular/anatomia & histologia , Osso Esfenoide/anatomia & histologia
8.
Headache ; 33(7): 390-3, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8376101

RESUMO

This study investigated the efficacy of methylergonovine maleate (Methergine) in the treatment of drug induced refractory headache (DIRH). Sixty consecutive patients (51 female and 9 male) diagnosed with DIRH were treated with methylergonovine maleate for a maximum of six months, using a within subject design. All patients were withdrawn from the medications they were taking upon entering the study. Concurrently, they were given 0.2-0.4 mg of methylergonovine maleate three times a day. Patients were provided the means to control breakthrough episodes of headache. Treatment outcome was assessed using a patient self-report scale (much better, better, same, worse, and much worse), and also visual analogue pain intensity scales. The side effects of the drug were assessed with patient self-report. Methylergonovine was effective in 44 (73%) patients. Twelve (20%) patients reported unchanged pain and 4 (6%) patients got worse. Side effects were reported by 24 patients. These were predominantly abdominal cramping. It is concluded that methylergonovine maleate is effective in the initial control of drug induced refractory headache. However, because methylergonovine is a metabolic byproduct of methysergide, the possibility or fibrotic disorders needs to be considered if methylergonovine is to be used for long term therapy.


Assuntos
Cefaleia/induzido quimicamente , Cefaleia/tratamento farmacológico , Metilergonovina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Cefaleia/fisiopatologia , Humanos , Masculino , Metilergonovina/efeitos adversos , Pessoa de Meia-Idade , Medição da Dor , Fatores de Tempo
9.
Headache ; 33(3): 155-60, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8486515

RESUMO

This study investigated the long term effect of a peripheral sensory block using streptomycin sulphate on trigeminal neuralgia. A total of twenty subjects, thirteen with idiopathic trigeminal neuralgia (ITN) and seven with traumatic trigeminal neuralgia (TTN) were studied. A double-blind placebo controlled randomized design was used. After the clinical assessment subjects were randomly assigned to receive either 1 g of streptomycin with 3 ml 2% lidocaine, or 3 ml lidocaine alone. The injections were performed adjacent to the branches that served the painful site. These were intraoral injections, more specifically infraorbital and inferior alveolar blocks. Patients received five blocks of either streptomycin/lidocaine or lidocaine alone for a period of five consecutive weeks. On the sixth week they were crossed over. Measures of pain intensity and pain frequency were used to assess treatment outcome. Patients also recorded their side-effects. Repeated measures analysis of variance was used to compare the treatment outcomes between the active and placebo groups. There was no statistically significant differences in the treatment outcomes regarding frequency and intensity of pain attacks. The sensory function of the treated nerves was also not affected. Side effects including facial swelling and pain were a common finding in the patients receiving streptomycin. This study demonstrated no beneficial effects of streptomycin blockade for idiopathic and traumatic trigeminal neuralgia.


Assuntos
Bloqueio Nervoso , Neuralgia do Trigêmeo/terapia , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Lidocaína , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estreptomicina , Traumatismos do Nervo Trigêmeo , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/fisiopatologia
10.
Oral Surg Oral Med Oral Pathol ; 73(5): 519-25, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1518633

RESUMO

Referred pain in the midface and teeth is a common clinical feature of the cluster headache and cluster headache-like disorders. It is not unusual therefore for patients with cluster headaches to go to the dentist. In this report, 33 cases of cluster headache, which met the International Headache Society classification criteria, and which were seen by us during a 2-year period, are reviewed. Fourteen (42%) of 33 patients who were seen by dental practitioners and who received some form of ineffective dental or pharmacologic treatment are described here. Since almost 50% of the cluster headache patients described here received inappropriate dental treatment, it is hoped that this review and retrospective assessment will make the dental practitioner aware of this disorder and provide a broader perspective in the treatment of pain in the orofacial region. Clinical presentation, pathogenesis, and treatment of cluster headaches are discussed.


Assuntos
Cefaleia Histamínica/diagnóstico , Dor Facial/diagnóstico , Adulto , Cefaleia Histamínica/fisiopatologia , Cefaleia Histamínica/terapia , Erros de Diagnóstico , Feminino , Humanos , Masculino , Qualidade da Assistência à Saúde , Estudos Retrospectivos
12.
Am J Emerg Med ; 9(6): 557-9, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1930398

RESUMO

To determine the feasibility and safety of an immediate, symptom-limited, treadmill test on selected emergency department (ED) patients, a convenience sample of 28 patients underwent an exercise treadmill test (ETT) within the first several hours after hospital arrival using the modified Bruce protocol. Patients were included in the study if they presented with otherwise unexplained chest pain consistent with (but not characteristic for) angina pectoris and had a normal electrocardiogram. A negative ETT was seen in 23 of 28 patients, and five of 28 patients had a positive ETT. No patients had serial enzyme or electrocardiogram evolution suggestive of myocardial ischemia, and all patients with a negative ETT were discharged after a full inpatient evaluation designed to rule out unstable coronary disease. At a mean follow-up period of 6.1 months there has been no cardiac morbidity or mortality in the patients with negative ETTs. It was concluded that early ETTS of selected ED patients with chest pain is safe, and an exercise test administered during the ED visit which is negative can preclude unnecessary hospitalization.


Assuntos
Dor no Peito , Teste de Esforço , Adulto , Doença das Coronárias/diagnóstico , Emergências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança
14.
Chest ; 99(6): 1415-20, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2036824

RESUMO

OBJECTIVE: to determine the relation of serum theophylline concentrations (STC) to the occurrence of cardiac arrhythmias in a population of hospitalized patients. STUDY DESIGN: A cross-sectional study of 100 patients receiving theophylline who had electrocardiograms at the time STC had been obtained. Categorization was based on STC without knowledge of clinical status: group 1 (25) had STC less than 2.5 mg/L; group 2 (25), STC greater than or equal to 2.5 less than 10 (6.2 +/- 0.4) mg/L; group 3 (25), STC greater than or equal to 10 less than or equal to 20 (15.8 +/- 0.4) mg/L; and group 4 (25), STC greater than 20 (27.8 +/- 1.1) mg/L. SETTING: A university-affiliated teaching hospital. RESULTS: Two-thirds of the patients were receiving theophylline in an oral form, with a similar distribution found in all groups. Groups were not different with respect to age, clinical diagnoses, electrocardiographic patterns, arterial pH or gases, serum calcium, or treatment with beta-agonists. Although fewer patients in group 1 were receiving steroids than those in the other groups, and serum potassium was lower in group 3 than in group 1 (4.0 +/- 0.6 vs 4.5 +/- 0.5 mEq/L, p less than 0.05), on multivariate analysis, serum potassium was not an independent predictor of arrhythmia, and treatment with steroids or digoxin was, at most, only weakly associated with the presence of arrhythmia. Heart rate was directly related to STC (r = 0.64, p less than 0.01), and STC was the strongest independent predictor of arrhythmia in this population. Although only 20 percent of patients in group 1 or 2 had arrhythmias, 48 percent of group 3 (p less than 0.05) and 56 percent of group 4 (p less than 0.05) had this finding. Moreover, the odds ratio of group 3 having an arrhythmia compared with group 1 was 3.7, 1.5 to 11.7, p less than 0.01. Multifocal atrial tachycardia was found in 8 percent of the patients in group 3 and 16 percent in group 4 but in none of the patients in groups 1 or 2. Two patients with multifocal atrial tachycardia died suddenly within 24 hours of having their STC measurement; none had concomitant ventricular ectopy. CONCLUSION: Theophylline causes tachycardia and serious arrhythmias even at STC considered to be therapeutic. Multifocal atrial tachycardia, an arrhythmia associated with use of this drug, may herald sudden cardiac death.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Teofilina/efeitos adversos , Idoso , Arritmias Cardíacas/diagnóstico , Asma/tratamento farmacológico , Estudos Transversais , Eletrocardiografia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Pneumopatias Obstrutivas/tratamento farmacológico , Masculino , Análise Multivariada , Potássio/sangue , Teofilina/sangue
15.
J Pharmacol Exp Ther ; 257(1): 214-8, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2019987

RESUMO

To assess the actions of theophylline on coronary blood flow and myocardial energetics, 1 mg/kg/min of this methylxanthine was infused i.v. in the dog for 15 min, producing an average concentration of 18 +/- 3 micrograms/ml. Heart rate increased by 20 +/- 7 min-1, P less than .05, but left ventricular (LV) systolic and end-diastolic pressures, cardiac output and LV peak dp/dt did not change. Although coronary vascular resistance decreased by 0.26 +/- 0.08 mm Hg/ml/min, P less than .05, coronary flow and myocardial oxygen consumption and extraction did not change. Myocardial lactate extraction decreased, from 22 +/- 2 to 1 +/- 5%, P less than .05. The decrement in lactate extraction was not related to heart rate, but to the change in LV peak dp/dt, r = 0.74, P less than .05. Furthermore, with verapamil, 0.2 mg/kg, pretreatment, and 0.2 mg/kg, during the theophylline infusion, reduction in lactate extraction was blocked and LV peak dp/dt increased by 843 +/- 311 mm Hg/sec, P less than .05. Thus, at therapeutic concentrations, theophylline reduces myocardial lactate extraction, an effect that is associated with the absence of the expected inotropic actions of theophylline. However, when verapamil is administered with theophylline, a reduction of myocardial extraction does not occur and myocardial inotropy is enhanced.


Assuntos
Coração/efeitos dos fármacos , Lactatos/metabolismo , Teofilina/efeitos adversos , Verapamil/farmacologia , Animais , Circulação Coronária/efeitos dos fármacos , Cães , Hemodinâmica/efeitos dos fármacos , Ácido Láctico , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Teofilina/antagonistas & inibidores , Teofilina/sangue
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