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1.
J Biol Regul Homeost Agents ; 32(2 Suppl. 2): 31-36, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29720328

RESUMO

Patients in treatment with rapid palatal expander (RPE) require professional assistance and more meticulous instructions on oral hygiene, since this appliance predisposes to gingivitis and caries. The aim of this work is to analyse the variability of the oral microbial flora found in patients in treatment with RPE with occlusal acrylic splint. It was also investigated whether the association of an antimicrobial mouthwash was useful during orthodontic treatment or whether regular and specific home oral hygiene manoeuvres were sufficient to maintain a good plaque control. The last goal was to highlight which of the different mouthwashes was the most effective in reducing the bacterial load. The patients were divided into 3 test groups and each one of them had a different mouthwash (chlorhexidine and sodium fluoride, fluorine, essential oils) randomly assigned. There was also a control group. Plaque samples were analysed through cultural analysis and PCR from T0 to T4 (8 months). Chlorhexidine mouthwash reduces the bacterial count by 96.08%, the fluorine by 94.50% and the essential oils by 95.74%. The results of the three mouthwashes are superimposable and although chlorhexidine gives the highest rate of bacteria reduction, its side effects lead the authors to prefer the essential oils.


Assuntos
Bactérias/isolamento & purificação , Placa Dentária/microbiologia , Placa Dentária/prevenção & controle , Técnica de Expansão Palatina , Periodonto/microbiologia , Dente/microbiologia , Bactérias/efeitos dos fármacos , Clorexidina/farmacologia , Placa Dentária/tratamento farmacológico , Flúor/farmacologia , Humanos , Antissépticos Bucais/farmacologia , Óleos Voláteis/farmacologia , Periodonto/efeitos dos fármacos , Fluoreto de Sódio/farmacologia , Dente/efeitos dos fármacos
2.
Acta Neurol Scand ; 132(3): 196-202, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25691245

RESUMO

OBJECTIVES: Fever frequently occurs in stroke patients and worsens their prognosis. However, only few studies have assessed the determinants of fever in acute stroke, and no study has specifically addressed the possible prediction of the development of fever. MATERIALS AND METHODS: This investigation included 536 patients with acute stroke and a body temperature <=37°C during the first 24 h of stay. Ninety-two of them (17.2%) subsequently developed fever (defined as a temperature >=37.5°C starting after 24 h). Among the clinical variables available during the first 24 h from admission, those predictive of the subsequent appearance of fever were searched for. One hundred further patients had a temperature >37°C during the first 24 h. RESULTS: In univariate analysis, many variables were predictive of the subsequent development of fever, but in multivariate analysis, only the following four predictors remained significant (odds ratio [95% confidence interval], P value): nasogastric tube (4.0 [2.2-7.4], <0.0001), atrial fibrillation (2.3 [1.4-3.8], 0.001), total anterior circulation syndrome (2.0 [1.2-3.5], 0.01), and urinary catheter (1.9 [1.1-3.3], 0.01). Among the 52 (9.7%) patients with three or four predictors, 31 (59.6%) subsequently developed fever. In addition, the factors independently associated with a temperature >37°C during the first 24 h were as follows: National Institutes of Health Stroke Scale (P < 0.0001), hemorrhagic stroke (P = 0.0008), atrial fibrillation (P = 0.002), and total parenteral nutrition (P = 0.03). CONCLUSIONS: In patients with acute stroke, four clinical variables were found to be independently associated with the risk of developing fever and, of them, nasogastric tube was the strongest and most significant one.


Assuntos
Febre/etiologia , Intubação Gastrointestinal/efeitos adversos , Acidente Vascular Cerebral/complicações , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prognóstico , Fatores de Risco , Estados Unidos
3.
Knee Surg Sports Traumatol Arthrosc ; 20(3): 468-86, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22068267

RESUMO

UNLABELLED: Young patients with early osteoarthritis (OA) represent a challenging population due to a combination of high functional demands and limited treatment options. Conservative measures such as injection and physical therapy can provide short-term pain relief but are only palliative in nature. Joint replacement, a successful procedure in the older population, is controversial in younger patients, who are less satisfied and experience higher failure rates. Therefore, while traditionally not indicated for the treatment of OA, cartilage repair has become a focus of increased interest due to its potential to provide pain relief and alter the progression of degenerative disease, with the hope of delaying or obviating the need for joint replacement. The field of cartilage repair is seeing the rapid development of new technologies that promise greater ease of application, less demanding rehabilitation and better outcomes. Concurrent procedures such as meniscal transplantation and osteotomy, however, remain of crucial importance to provide a normalized biomechanical environment for these new technologies. LEVEL OF EVIDENCE: Systematic review, Level II.


Assuntos
Cartilagem Articular/cirurgia , Osteoartrite do Joelho/cirurgia , Progressão da Doença , Humanos , Osteotomia , Transplante Homólogo , Resultado do Tratamento
4.
Acta Neurol Scand ; 124(5): 334-42, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21241255

RESUMO

OBJECTIVES: According to most existing models, a computer is usually needed for predicting stroke outcome. Our purpose was to construct a simple and reliable prognostic scale not requiring the use of a calculating machine. MATERIALS AND METHODS: The scale [the Bologna Outcome Algorithm for Stroke (BOAS)] was obtained in 221 patients with ischemic stroke not undergoing thrombolysis and was then validated in a test group of 100 different patients. Outcome was assessed at 9 months as the number of dependent or dead patients (modified Rankin scale - mRS > 2). RESULTS: By a preliminary systematic univariate analysis, 25 of 415 baseline variables were found to be associated with a mRS > 2 independently of stroke severity and age. Subsequent multivariable analyses led to a final model based on five dichotomous risk factors (RF): National Institutes of Health Stroke Scale score ≥10, age ≥78, need of urinary catheter, oxygen administration, and persistence of upper limb paralysis at discharge from stroke unit. The patients with two or more RF (53%) had a mRS > 2 in 91% of cases and were dead in 42% of cases. With 0-1 RF, the two percentages were 24% and 2%, respectively (overall accuracy of prediction 83.9%, area under ROC curve [AUC] 0.891). In the test group, the accuracy was 79.0% and the AUC was 0.839. CONCLUSIONS: The need of urinary catheter, oxygen administration, and persistence of upper limb paralysis, together with stroke severity and advanced age, allow a simple and accurate prediction of dependency or death after ischemic stroke.


Assuntos
Algoritmos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/mortalidade , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/mortalidade , Isquemia Encefálica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Terapia Trombolítica
6.
Phys Rev Lett ; 100(2): 022302, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18232858

RESUMO

The NA60 experiment at the CERN SPS has studied low-mass dimuon production in 158A GeV In-In collisions. An excess of pairs above the known meson decays has been reported before. We now present precision results on the associated transverse momentum spectra. The slope parameter Teff extracted from the spectra rises with dimuon mass up to the rho, followed by a sudden decline above. While the initial rise is consistent with the expectations for radial flow of a hadronic decay source, the decline signals a transition to an emission source with much smaller flow. This may well represent the first direct evidence for thermal radiation of partonic origin in nuclear collisions.

7.
Phys Rev Lett ; 99(13): 132302, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17930580

RESUMO

The NA60 experiment studies muon pair production at the CERN Super Proton Synchrotron. In this Letter we report on a precision measurement of J/psi in In-In collisions. We have studied the J/psi centrality distribution, and we have compared it with the one expected if absorption in cold nuclear matter were the only active suppression mechanism. For collisions involving more than approximately 80 participant nucleons, we find that an extra suppression is present. This result is in qualitative agreement with previous Pb-Pb measurements by the NA50 experiment, but no theoretical explanation is presently able to coherently describe both results.

8.
Phys Rev Lett ; 96(16): 162302, 2006 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-16712218

RESUMO

We report on a precision measurement of low-mass muon pairs in 158 AGeV indium-indium collisions at the CERN SPS. A significant excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size of 360,000 dimuons and the good mass resolution of about 2% allow us to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum is consistent with a dominant contribution from pi+pi- -->rho -->mu+mu- annihilation. The associated space-time averaged spectral function shows a strong broadening, but essentially no shift in mass. This may rule out theoretical models linking hadron masses directly to the chiral condensate.

9.
Int J Clin Pract ; 59(4): 462-72, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15853866

RESUMO

Atherosclerosis (ATS) is a multifactorial disease caused by the interaction of established or emerging risk factors with multiple predisposing genes that regulate ATS-related processes. This review will discuss the current knowledge concerning the potential role of the genetic variations that could promote and/or accelerate ATS, in both animal models and humans. Allelic polymorphisms or variations of distinct genes that enhance the risk of ATS frequently occur in the general population, but only adequate gene-environment interactions will lead to the disease. The main genes so far studied are involved in the regulation of processes such as endothelial function, antioxidant potential, coagulation, inflammatory response, and lipid, protein and carbohydrate metabolism. The detection of candidate genes associated with ATS could allow, in the near future, earlier interventions in genetically susceptible individuals. Further, large-scale population studies are needed to obtain more information on the specific gene-environment and drug-gene interactions capable of influencing ATS progression.


Assuntos
Arteriosclerose/genética , Predisposição Genética para Doença/genética , Lipídeos/genética , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Arildialquilfosfatase/genética , Coagulação Sanguínea/genética , Expressão Gênica , Genótipo , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Modelos Biológicos , Mutação/genética , Polimorfismo Genético/genética , Sistema Renina-Angiotensina/genética , Fatores de Risco
10.
Orthopade ; 33(2): 185-92, 2004 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-14872310

RESUMO

This review presents a novel technique for open-wedge varus osteotomies of the distal femur in lateral compartment osteoarthritis in valgus knees. Indications and contraindications are discussed. The technique, its potential pitfalls, and postoperative management are presented. The authors' results with this technique are compared to the data of the literature.


Assuntos
Mau Alinhamento Ósseo/cirurgia , Fêmur/cirurgia , Articulação do Joelho/cirurgia , Osteotomia/instrumentação , Adulto , Mau Alinhamento Ósseo/diagnóstico por imagem , Placas Ósseas , Parafusos Ósseos , Feminino , Fêmur/diagnóstico por imagem , Humanos , Articulação do Joelho/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia , Instrumentos Cirúrgicos
11.
Clin Ter ; 154(1): 39-43, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-12854282

RESUMO

Progressive increase of the average lifespan pushed up the number of the elderlies in the population. The subsequent spread of degenerative conditions such as osteoarthritis has inflated the request of NSAID despite their frequent toxicity. Side effects of NSAID are sometimes severe and mainly target gastrointestinal tract, renal and platelets function. It has been estimated that around 70% of the patients treated with NSAID develop some degree of gastric damage, ranging from aspecific dyspeptic syndromes to ulcerative diseases. Drugs are now available that selectively inhibit the cyclooxygenase-2: this enzyme is involved in the synthesis of prostaglandins during the inflammatory response. These new drugs have opened new perspectives in the treatment of arthritis; they allow COX-1 to work regularly, so that those prostaglandins that are involved in the maintenance of a regular function of the gastrointestinal tract mucosa and of the platelets. Celecoxib was the firstborn of these new drugs. Differently from FANS, COXIB has got less side effects on gastrointestinal tract and platelets function. Based on the evidence of the more recent clinical experience COXIB has to be recommended; in particular celecoxib, at a schedule of 200-400 mg/die, was shown to be highly effective in the symptomatic treatment of osteoarthritis and rheumatoid arthritis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Isoenzimas/antagonistas & inibidores , Osteoartrite/tratamento farmacológico , Sulfonamidas/uso terapêutico , Idoso , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Celecoxib , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/administração & dosagem , Inibidores de Ciclo-Oxigenase/efeitos adversos , Humanos , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases , Pirazóis , Fatores de Risco , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Fatores de Tempo
12.
Int Endod J ; 35(2): 148-52, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11843969

RESUMO

AIM: This study describes the use of a real time-ultrasound imaging technique (echography) for the study of periradicular lesions. METHODOLOGY: Twelve patients with periapical lesions of endodontic origin, diagnosed with conventional clinical and radiographic examination, were examined further using echography at the site of the diagnosed lesions. Each lesion was echographically characterized and described by an expert echographist together with an endodontist. Once the major echographic features were identified, information on the size of the lesion, its content, and its vascular supply was obtained and recorded. A tentative differential diagnosis between a cyst and a granuloma was made based on the data. RESULTS: In all cases it was possible to obtain an echographic image. It was also possible to measure the lesions, to evaluate their content and to view their vascularization in different regions of the mouth. CONCLUSIONS: Ultrasound real time imaging is a promising diagnostic technique in endodontology, but further work is required to refine the process.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Periodontite Periapical/diagnóstico por imagem , Humanos , Reprodutibilidade dos Testes , Ultrassonografia
13.
Acta Cardiol ; 56(4): 225-31, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11573827

RESUMO

The HMG-CoA reductase inhibitors (statins) are now considered the most potent lipid-lowering drugs. Treatment with statins reduces both morbidity and mortality rates due to coronary artery disease. There is now increasing evidence that the clinical benefits obtained with statins cannot be solely attributed to a decrease in low-density lipoprotein (LDL) level. These drugs may also have beneficial effects on endothelial dysfunction, LDL oxidation, rheological and thrombogenic factors, cellular inflammation and plaque formation and stability. Further, there are differences among the various statins on these non-lipid variables. The biochemical effects of statins, as well as their clinical benefits, should be taken into consideration.


Assuntos
LDL-Colesterol/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Humanos
14.
Cardiology ; 95(1): 9-13, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11385185

RESUMO

Endothelial dysfunction is an early event in atherosclerosis and could be considered a response to the injury induced by major risk factors. There is evidence that endothelial dysfunction is intimately involved in the onset and the progression of cardiovascular disease through abnormalities in the production, release or degradation of endothelium-derived factors, mainly nitric oxide and endothelin 1. Several reports have shown that drugs of the statin class could have multiple beneficial effects related to endothelium-mediated vasoactive, antithrombotic, antiproliferative and anti-inflammatory actions. Thus, the question arises of whether endothelial cells are the main target of statin therapy, in the setting of both hypercholesterolemia and normocholesterolemia. Experimental and clinical studies are reported that could support this hypothesis.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Animais , Anticolesterolemiantes/farmacologia , Arteriosclerose/imunologia , Arteriosclerose/fisiopatologia , Endotelina-1/efeitos dos fármacos , Endotelina-1/fisiologia , Endotélio Vascular/fisiologia , Humanos , Óxido Nítrico/fisiologia
15.
J Chromatogr B Biomed Sci Appl ; 751(1): 153-60, 2001 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-11232845

RESUMO

A reversed-phase high-performance liquid chromatography (HPLC) method with diode-array detection for the quantification of several human salivary peptides is described. Sample pretreatment consisted of the acidification of whole saliva by phosphate buffer. This treatment produced precipitation of mucins, alpha-amylases and other high-molecular-mass salivary proteins, simultaneous inhibition of intrinsic protease activities and reduction of sample viscosity. Direct HPLC analysis by diode-array detection of the resulting acidic sample allowed one to quantify histatin 1, histatin 3, histatin 5, statherin, as well as uric acid, in normal subjects. Moreover, the groups of peaks pertaining to proline-rich proteins and cystatins were tentatively identified. The method can be useful in assessing the concentration of salivary peptides from normal subjects and from patients suffering oral and/or periodontal diseases.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fosfopeptídeos/análise , Proteínas/análise , Proteínas e Peptídeos Salivares/análise , Ácidos , Soluções Tampão , Histatinas , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Acta Cardiol ; 55(4): 221-32, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11041120

RESUMO

Endothelial cells release both relaxing and contracting factors that modulate vascular smooth muscle tone and also participate in the pathophysiology of essential hypertension. Endothelium-dependent vasodilation is regulated primarily by nitric oxide but also by an unidentified endothelium-derived hyperpolarizing factor and by prostacyclin. Endothelium-derived contracting factors include endothelin-1, vasoconscrictor prostanoids, angiotensin II and superoxide anions. Under physiological conditions, there is a balanced release of relaxing and contracting factors. The balance can be altered in cardiovascular diseases such as hypertension, atherosclerosis, diabetes and other conditions, thereby contributing to further progression of vascular and end-organ damage. In particular, endothelial dysfunction leading to decreased bioavailability of nitric oxide impairs endothelium-dependent vasodilation in patients with essential hypertension and may also be a determinant for the premature development of atherosclerosis. Different mechanisms of reduced nitric oxide activity have been shown both in hypertensive states and several cardiovascular diseases, and endothelial dysfunction is likely to occur prior to vascular dysfunction. Thus, the strategies currently used to improve endothelial dysfunction may result in decreased morbidity and mortality in hypertensive patients.


Assuntos
Endotélio Vascular/fisiopatologia , Hipertensão/fisiopatologia , Angiotensina II/fisiologia , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Arginina/metabolismo , Ensaios Clínicos como Assunto , Endotelina-1/fisiologia , Endotelinas/fisiologia , Endotélio Vascular/efeitos dos fármacos , Radicais Livres , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Óxido Nítrico/fisiologia , Ratos , Ratos Endogâmicos SHR , Pesquisa , Fatores de Risco , Vasodilatação/fisiologia
17.
Arthroscopy ; 16(2): 217-20, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10705337

RESUMO

The purpose of this report is to present a new radiological method of diagnosis and evaluation of posterior instability using the patellofemoral axial view. During a period of 22 months, we performed clinical and radiological assessments on 20 patients (6 acute and 14 chronic) with isolated posterior instability caused by posterior cruciate ligament (PCL) rupture and on 20 patients with normal knees. The radiological examination included stress radiographs using the Telos device (Telos, Griesheim, Germany) as well as a modification of the routine axial patellofemoral view. Both diagnosis and quantification of the posterior tibial translation was possible in all cases by measuring, on the axial view, the distance between the anterior edge of the tibial plateau and the center of the femoral groove (trochlea). Clinical examination, conventional radiography, KT-1000 arthrometry, stress radiography at 90 degrees and at 20 degrees of flexion, and magnetic resonance imaging all assist in diagnosing a PCL tear. This new radiographic technique is simple, fast, and consistently effective both in patients with acute and those with chronic PCL tears, as well as in those who have undergone PCL reconstruction.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Joelho/diagnóstico por imagem , Ligamento Cruzado Posterior/lesões , Adulto , Artrografia/métodos , Feminino , Humanos , Masculino , Ligamento Cruzado Posterior/diagnóstico por imagem , Ruptura , Decúbito Dorsal , Tíbia/diagnóstico por imagem
18.
Clin Ter ; 150(6): 439-43, 1999.
Artigo em Italiano | MEDLINE | ID: mdl-10756664

RESUMO

It has been demonstrated that beta blockers are able to modify the course of the disease, through the reduction of hemodynamic in stabilization and mortality cases. The success of these drugs in the treatment of chronic heart failure is related to the sympathoadrenergic activation and to renin-angiothensin-aldosteron system. Various molecules are available at the moment. Recent research has been done on third generation beta blockers (carvedilol, nebivolol, bucindolol). These drugs have shown to possess some peculiar characteristics, in particular the ability of reducing the number of side effects which may be seen while using beta blockers of the first generations. Although it is currently difficult to give general informations based only on the pharmacologic profile, the choice of the type of drug to use in the single patient with chronic heart failure should be made considering the adequacy of the pharmacologic characteristics in each specific situation.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Humanos
19.
Arthroscopy ; 14(8): 840-3, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9848596

RESUMO

In overuse clinical conditions in and around tendons, frank inflammation is infrequent, and is associated mostly with tendon ruptures. Tendinosis implies tendon degeneration without clinical or histological signs of intratendinous inflammation, and is not necessarily symptomatic. Patients undergoing an operation for Achilles tendinopathy show similar areas of degeneration. When the term tendinitis is used in a clinical context, it does not refer to a specific histopathological entity. However, tendinitis is commonly used for conditions that are truly tendinoses, and this leads athletes and coaches to underestimate the proven chronicity of the condition. Paratenonitis is characterized by acute edema and hypermia of the paratenon, with infiltration of inflammatory cells, possibly with production of a fibrinous exudate that fills the tendon sheath, causing the typical crepitus that can be felt on clinical examination. The term partial tear of a tendon should describe a macroscopically evident subcutaneous partial tear of a tendon, an uncommon acute lesion. Most articles describing the surgical treatment of 'partial tears' of a given tendon in reality deal with degenerative tendinopathies. The combination of pain, swelling, and impaired performance should be labeled tendinopathy. According to the tissues affected, the terms tendinopathy, paratendinopathy, or pantendinopathy should be used.


Assuntos
Tendinopatia/patologia , Tendões/patologia , Terminologia como Assunto , Humanos
20.
G Ital Cardiol ; 28(3): 242-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9561878

RESUMO

BACKGROUND: During acute myocardial infarction, the ascending branch of creatine kinase curves has a sigmoidal course whose inflection point marks the maximum rate of enzymatic increase in serum. This study was performed to assess the relationship between these morphologic characteristics of creatine kinase curves and the progression of myocardial necrosis. METHODS AND RESULTS: In isolated rat hearts exposed to different degrees of ischemia (coronary flow of 0.6 or 0.2 ml/g/min), the total quantity of creatine kinase released in the effluent had a sigmoidal course similar to the ascending branch of the curves from patients with acute myocardial infarction. Other rat hearts were frozen (which causes maximum damage to cell structures), thawed and then perfused. The resulting enzymatic curves had a downward concave ascending trend, similar to the portion beyond the inflection point of sigmoidal curves (the rate of creatine kinase release was maximum at the onset of perfusion and then decreased progressively). Finally, in some experiments ischemic rat hearts were further damaged by the perfusion, at different times, with highly concentrated catecholamines and without oxygen and substrates. This damaging perfusate was able to increase the rate of creatine kinase release (p = 0.0001) only when it was started before the inflection point of enzymatic curves. In 25 creatine kinase curves from patients with acute myocardial infarction (19 men and 6 women, age range 42 to 68 years), who were not treated with thrombolysis, the time of inflection varied from 1 to 12 hours from the onset of symptoms, with a maximum frequency between the 7th and the 8th hour. CONCLUSIONS: Based on these data, a biological model with 3 compartments has been suggested to explain the shape of creatine kinase curves, according to which the inflection point would occur after the completion of myocardial necrosis. The variability of the time of inflection might account for the cases of beneficial late thrombolysis reported in literature.


Assuntos
Infarto do Miocárdio/enzimologia , Terapia Trombolítica , Adulto , Idoso , Animais , Creatina Quinase/sangue , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Isquemia Miocárdica/enzimologia , Necrose , Ratos , Ratos Sprague-Dawley
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