Leptospira and inflammation.

Leptospirosis is an important zoonosis and has a worldwide impact on public health. This paper will discuss both the role of immunogenic and pathogenic molecules during leptospirosis infection and possible new targets for immunotherapy against leptospira components. Leptospira, possess a wide variety of mechanisms that allow them to evade the host immune system and cause infection. Many molecules contribute to the ability of Leptospira to adhere, invade, and colonize. The recent sequencing of the Leptospira genome has increased our knowledge about this pathogen. Although the virulence factors, molecular targets, mechanisms of inflammation, and signaling pathways triggered by leptospiral antigens have been studied, some questions are still unanswered. Toll-like receptors (TLRs) are the primary sensors of invading pathogens. TLRs recognize conserved microbial pattern molecules and activate signaling pathways that are pivotal to innate and adaptive immune responses. Recently, a new molecular target has emerged--the Na/K-ATPase--which may contribute to inflammatory and metabolic alteration in this syndrome. Na/K-ATPase is a target for specific fatty acids of host origin and for bacterial components such as the glycolipoprotein fraction (GLP) that may lead to inflammasome activation. We propose that in addition to TLRs, Na/K-ATPase may play a role in the innate response to leptospirosis infection.

Tympanometry in neonates with normal otoacoustic emissions: measurements and interpretation.

UNLABELLED: Tympanometry is used in evaluating middle ear functional conditions. Before six months of age its results may be misleading. High frequency studies aim to provide more valid procedures. AIM: To describe and discuss tympanometric measurements and the interpretation in normal hearing neonates at 226, 678 and 1000Hz. METHOD: 110 neonates that were analyzed had normal otoacoustic emissions and no risk for hearing impairment. The age range was 6 to 30 days. Curves were obtained using the GSI-33-II, at the Divisão de Educação e Reabilitação dos Distúrbios da Comunicação, São Paulo, in 2004. STUDY DESIGN: Clinical prospective. RESULTS: There was a balance between single and double peak curves at 226Hz. Most of the curves were asymmetric at 678Hz, and single-peaked at 1000Hz. quantitative measurements showed a significant gender difference in the Equivalent Ear Canal Volume at 226Hz and on the Peak Compensated Static Acoustic Admittance at 1000Hz. The English protocol showed that almost 100% of ears were normal at 678 and 1000Hz. CONCLUSION: 1000Hz yielded superior results for characterizing normality. The English protocol was efficient to reduce the variability of tympanometric measurements. Data from this study may be used as a guide for diagnosis using tympanometry in neonates.

Achados timpanométricos em neonatos com emissões otoacústicas presentes: medidas e interpretações / Tympanometry in neonates with normal otoacoustic emissions: measurements and interpretation

Timpanometria avalia condições funcionais da orelha média. Quando realizada em neonatos abaixo de quatro meses de idade pode gerar dúvidas. Sondas de alta freqüência têm sido investigadas na busca por resultados mais confiáveis. OBJETIVO: Descrever e analisar interpretações de características e medidas obtidas na timpanometria em neonatos com freqüências de 226, 678 e 1000Hz. MATERIAL E MÉTODO: Os 110 neonatos avaliados tinham idade entre 6 e 30 dias, não apresentaram fatores de risco e tinham emissões otoacústicas presentes. A timpanometria foi realizada com o analisador GSI-33-II, na Divisão de Educação e Reabilitação dos Distúrbios da Comunicação, São Paulo, em 2004. FORMA DE ESTUDO: Clínico prospectivo. RESULTADOS: Observou-se equilíbrio nas curvas pico único e pico duplo em 226Hz, maior ocorrência de assimétrica em 678Hz e de pico único em 1000 Hz. Houve significância de gênero na medida volume equivalente do meato acústico externo, em 226Hz, e na medida admitância acústica estática de pico compensado, em 1000Hz. O protocolo inglês apresentou quase 100 por cento de normalidade em 678 e 1000Hz. CONCLUSÃO: A sonda de 1000Hz apresentou melhores resultados na caracterização da normalidade. O protocolo inglês mostrou-se eficiente em diminuir variabilidades das medidas. Os resultados podem ser usados como guia no diagnóstico da timpanometria.

Tympanometry is used in evaluating middle ear functional conditions. Before six months of age its results may be misleading. High frequency studies aim to provide more valid procedures. AIM: To describe and discuss tympanometric measurements and the interpretation in normal hearing neonates at 226, 678 and 1000Hz. METHOD: 110 neonates that were analyzed had normal otoacoustic emissions and no risk for hearing impairment. The age range was 6 to 30 days. Curves were obtained using the GSI-33-II, at the Divisão de Educação e Reabilitação dos Distúrbios da Comunicação, São Paulo, in 2004. STUDY DESIGN: Clinical prospective. RESULTS: There was a balance between single and double peak curves at 226Hz. Most of the curves were asymmetric at 678Hz, and single-peaked at 1000Hz. quantitative measurements showed a significant gender difference in the Equivalent Ear Canal Volume at 226Hz and on the Peak Compensated Static Acoustic Admittance at 1000Hz. The English protocol showed that almost 100 percent of ears were normal at 678 and 1000Hz. CONCLUSION: 1000Hz yielded superior results for characterizing normality. The English protocol was efficient to reduce the variability of tympanometric measurements. Data from this study may be used as a guide for diagnosis using tympanometry in neonates.

[Mucocutaneous leishmaniasis in Brazilian Amazonia]. / Leishmaniose cutanéomuqueuse en Amazonie brésilienne.

BACKGROUND: This study had for aim to describe the clinical aspects and favoring factors of mucosal Leishmaniasis in an Amazonian population of 30,000 habitants in Guajara-Mirim (Rondonia-Brazil). MATERIAL AND METHOD: A descriptive study was made of 16 patients with mucosal Leishmaniasis among 170 patients infected by Leishmania. Inclusion criteria were a mucosal lesion and positivity of direct microscopic examination. The patients were investigated retrospectively. RESULTS: Patients with mucosal Leishmaniasis were young and mostly male The absence of treatment and the number of cutaneous lesions were probably responsible for the mucosal form, as well as the host immune response and maybe, the parasite species or vector characteristics. CONCLUSION: The mucosal form of leishmaniasis affects more often young male patients and this form must be detected early to avoid destructing lesions.

Cervicography as an adjunctive test to visual inspection with acetic acid in cervical cancer detection screening.

OBJECTIVE: Validate Digital Cervicography as adjunctive cervical cancer screening test to VIA and Cytology. METHOD: Women (1292) were submitted to both cytological and VIA tests to obtain a sample of 301 positive VIA cases (23.3%) which have had the Digital Cervicography (DC) taken and evaluated. Just cases considered positive by DC (149/301 cases--49.5%) and/or positive Pap smear tests were referred to colposcopy and biopsy whenever indicated. RESULTS: Cervical smear was positive in 5.4%, including LGSIL (4%), HGSIL (1%) and one case of invasive cancer (0.4%), and 1.6% of ASCUS or AGUS). DC identified 81 positive cases (74 LGSIL; 5 HGSIL; 2 cancers). The sensitivity of cytology was 14.8%, and the DC was 100%. Corresponding specificities were 95.4% and 69.1%, respectively. The NPV and PPV for DC were 100% and 54.4%. CONCLUSION: DC increases sensitivity, specificity and positive predictive value of VIA, becoming a valid adjunctive screening test for cervical cancer in low resource settings.

Immune defense mechanisms of Culex quinquefasciatus (Diptera: Culicidae) against Candida albicans infection.

Mosquitoes have an efficient defense system against infection. The cellular immune defense mechanism initiated by the mosquito Culex quinquefasciatus infected with the fungus Candida albicans was investigated in this study. Differences in the hemocyte counts in hemolymph perfused from uninoculated, saline-inoculated, and C. albicans-infected mosquitoes were compared using a light microscope. Phagocytosis was also investigated using electron microscopy. Four types of hemocytes were identified in control mosquitoes: prohemocytes (9.8%), plasmatocytes (38.8%), granular cells (44.2%), and oenocytoids (7.3%). Between 3 and 18 h postinoculation the total hemocyte count was significantly higher in infected, compared to uninfected, mosquitoes. Differential hemocyte counts from infected mosquitoes at 3, 6, and 18 h after inoculation showed that the relative proportion of plasmatocytes (48.6, 50.7, 45%) was higher and, concomitantly, the proportion of granular cells was lower (38, 36.8, 35%, respectively). Yeast cells were phagocytosed and limited growth was observed within the plasmatocytes. Melanized nodules were found attached to different insect tissues at 24 to 72 h following infection. These results suggest that phagocytosis, followed by nodule formation, was capable of clearing the hemolymph of yeast cells.

[First report of Aedes albopictus in areas of Mata Atlantica, Recife, PE, Brazil]. / Primeiro registro de Aedes albopictus em área da Mata Atlântica, Recife, PE, Brasil.

This is the first report of the presence of Aedes albopictus in the native rain forest, near the urban area of Recife (State of Pernambuco, Brazil). Adult female mosquitoes were collected using human bait. Mosquitoes in aquatic stages were looked for in treeholes, bamboos, bromeliads and old tires. The existence of Ae. albopictus in the metropolitan area of Recife poses a potential risk for the interaction of this mosquito species with the urban human population.

[Analysis of adequacy and effectiveness in the use of tocolytics in preterm labor]. / Anlise da adequação e da efetividade do uso de tocolíticos no trabalho de parto prematuro.

The objective of this study was to assess quality of care for premature labor at public maternity facilities in Rio de Janeiro, Brazil, using referents, indicators, and standards of care derived from scientific evidence. The standard utilized in the process analysis for use of betamimetic tocolytics was 100%, considering the related referents. For outcome analysis, the standard applied was the occurrence of premature delivery in 11% of patients within 24 h and in 24% of patients (referent) within 48 h of hospital admission. Use of tocolytics was observed in 18.7% of patients admitted in premature labor. At gestational age from 28 weeks to 33 weeks and 6 days, especially critical for neonatal survival, tocolytics were used in 32.6% of patients. Premature birth occurred in 59% of patients within 24 h and in 64% within 48 h. These outcomes were consistent with the low rate of utilization of tocolytics. Effectiveness of care for preterm labor measured by rate of premature birth was low. Results of the corresponding process and outcomes analysis were consistent.

Normal high energy phosphate ratios in "stunned" human myocardium.

OBJECTIVES: We sought to investigate whether alterations in cardiac high energy phosphates occur in postischemic "stunned" human myocardium. BACKGROUND: Transient postischemic myocardial dysfunction is a common phenomenon that occurs in a variety of clinical settings in the absence of necrosis, and its pathogenesis is still unclear. Cardiac high energy phosphates are reduced during ischemia, and persistently altered myocardial high energy phosphate metabolism has been suggested as a mechanism contributing to stunning. METHODS: We studied 29 patients with a first anterior myocardial infarction (MI) who underwent successful reperfusion within 6 h of the onset of chest pain. These patients underwent 31P magnetic resonance spectroscopy (MRS) a mean of 4 days after MI for measurement of left ventricular contractility and relative high energy phosphate metabolites. Twenty-one patients underwent a second 31P MRS study a mean of 39 days after MI. Eight volunteers served as control subjects. RESULTS: Global and infarct area wall motion scores improved significantly between the early and late studies. No difference was found between early cardiac phosphocreatine (PCr)/beta-adenosine triphosphate (beta-ATP) ratios in patients and control subjects ([mean +/- SD] 1.51 +/- 0.17 vs. 1.61 +/- 0.18, respectively, p = 0.17) or between early and late study results in patients (1.51 +/- 0.17 vs. 1.53 +/- 0.17, respectively, p = 0.6). For alpha of 0.05, the study had a 90% power to detect a 9% difference. CONCLUSIONS: The results of this study demonstrate normal myocardial PCr/ATP ratios in patients with myocardial stunning after reperfusion and suggest that relative cardiac high energy phosphates are not depleted in stunned human myocardium.

Role of preischemic glycogen depletion in the improvement of postischemic metabolic and contractile recovery of ischemia-preconditioned rat hearts.

BACKGROUND: Ischemic preconditioning (IPC) attenuates acidosis during prolonged ischemia and improves contractile and metabolic parameters during subsequent reperfusion. Glycogen depletion induced by IPC is proposed as a potential mechanism. METHODS AND RESULTS: We studied the influence of manipulations of preischemic glycogen levels (Pre-G, micromol glucose/g wet wt) on contractile and metabolic (via 31P-nuclear magnetic resonance) parameters during 30 minutes of ischemia and recovery in four groups of isovolumic rat hearts: First, control (Con, n=18, mean Pre-G, 21.5+/-0.8); second, after two 5-minute IPC periods (IPC, n=12, Pre-G, 11.3+/-0.7); third, a control group in which Pre-G was depleted by glucose-free, acetate perfusion (Con-LowG, n=9, Pre-G, 7.9+/-1.2); and fourth, an IPC group in which Pre-G was raised by glucose and lactate perfusion such that Pre-G was similar to Con (IPC-HiG, n=11, Pre-G, 20+/-1.4). Manipulation of Pre-G significantly altered the pH fall during 30 minutes of ischemia (Con, 5.76+/-.03, Con-LowG, 6.26+/-.07; IPC-HiG, 5.91+/-.02, IPC, 6.05+/-.09). IPC-HiG hearts had significantly worse metabolic recovery (PCr, 70+/-7 versus 91+/-3% initial; IPC-HiG versus IPC, P<.05) and contractile recovery (end-diastolic pressure, 52+/-5 versus 29+/-5 mm Hg, P<.05) than IPC hearts but better recovery than Con (%PCr, 56+/-6% and end-diastolic pressure, 72+/-6 mm Hg). An ischemic rise in intracellular magnesium occurred and was atttenuated in preconditioned hearts. CONCLUSIONS: Pre-G levels before ischemia influence but are not the sole determinants of the extent of acidosis during prolonged ischemia and of metabolic and contractile recovery during reperfusion in control and preconditioned hearts.

Usefulness of ST-segment depression in non-infarct-related electrocardiographic leads in predicting prognosis after thrombolytic therapy for acute myocardial infarction.

This study investigated both the in-hospital and long-term prognostic significance of ST-segment depression in non-infarct-related leads in patients who received thrombolytic therapy after acute myocardial infarction (AMI). We evaluated 221 consecutive patients who were admitted with their first AMI and underwent thrombolysis. Patients were followed for an average of 31 months and were classified into 3 groups: group 1 included 51 patients with persistent ST-segment depression, group 2 had 97 patients with transient ST-segment depression, and group 3 consisted of 73 patients without ST-segment depression (absent). Group 1 had significantly worse long-term survival during follow up by Kaplan-Meier analysis (55%) versus group 2 (81%) and group 3 (94%) (p = 0.0004) and higher event rates. This prognostic significance seemed to be maintained in both the anterior and inferior wall AMI groups. Multivariate analysis, using the Cox model, showed that Killip class, in-hospital left ventricular ejection fraction, and the persistence of ST-segment depression on the predischarge electrocardiogram (group 1) were independent predictors of survival. ST-segment depression in non-infarct-related leads on the predischarge electrocardiogram is an independent risk factor for worse long-term survival after anterior as well as inferior AMI treated with thrombolytic therapy.

Attenuated glycogenolysis reduces glycolytic catabolite accumulation during ischemia in preconditioned rat hearts.

Prior transient episodes of ischemia ("ischemic preconditioning") reduce lactate accumulation and attenuate acidosis during a subsequent prolonged ischemic insult. The mechanisms responsible for attenuated glycolytic catabolite accumulation have not been established but may include earlier exhaustion of glycogen stores, slowed glycogenolysis before complete glycogen depletion, and/or inhibition of glycolysis. Simultaneous repeated measures of myocardial glycogen and the rates of glycolysis, glycogenolysis, glucose utilization, and glycolytic ATP production were obtained during total ischemia by 13C nuclear magnetic resonance spectroscopy in control and ischemia-preconditioned isolated rat hearts. Both [13C]glycolytic and [13C]glycogenolytic rates were significantly lower during total ischemia in preconditioned compared with control hearts (0.77 +/- 0.04 versus 1.06 +/- 0.06 mumol/min per gram wet weight [P < .01] for glycolysis and 0.15 +/- 0.07 versus 0.78 +/- 0.12 mumol/ min per gram wet weight [P < .001] for glycogenolysis, respectively, at 2.5 minutes of ischemia). Slowed glycolysis was present even during the early minutes of ischemia, when significant amounts of available [13C]glycogen were still present. Importantly, the reduction in the rate of glycogenolysis was larger and out of proportion to the reduction in glycolysis and occurred despite an increase in glucose utilization in preconditioned hearts (2.23 +/- 0.15 versus 1.5 +/- 0.10 mumol/min per gram wet weight at 1.25 minutes, P < .01). During early ischemia, conversion of glycogen phosphorylase to the a or "active" form was less in preconditioned than in control hearts (29.1 +/- 2.6% versus 41.2 +/- 9.8%, respectively; P < .05). Taken together, these findings demonstrate that ischemic preconditioning significantly depresses glycolytic catabolite accumulation during sustained ischemia not by more severe glycolytic inhibition or exhaustion of glycogen stores but by depressed glycogenolysis from the onset of ischemia.

[Analysis of elastic retraction in the 1st 15 minutes after coronary balloon angioplasty]. / Análise da retração elástica nos primeiros 15 minutos após angioplastia coronária por cateter balão.

PURPOSE: To determine the time course of elastic recoil (ER) in the first 15min after successful percutaneous transluminal coronary angioplasty (PTCA). METHODS: One hundred and fifty four patients, with stable or unstable angina were successfully submitted to PTCA. Coronary angiography was undertaken shortly after balloon deflation and repeated 5, 10 and 15 min thereafter. Quantitative coronary angiography was performed with the aid of an eletronic caliper. We calculated the minimal luminal diameter (MLD) and elastic recoil in all angiograms. RESULTS: The average artery's reference diameter was 3.09 +/- 0.61mm and the maximal balloon diameter was 2.95 +/- 0.52mm. MLD before the procedure was 0.65 +/- 0.42mm reaching 2.23 +/- 0.55mm immediately after dilatation (p < 0.0001), and decreasing to 2.09 +/- 0.47mm at 5min (p < 0.0001), 2.01 +/- 0.47 at 10min (p < 0.0001) and to 1.91 +/- 0.56mm at 15min (p < 0.0001). ER increased during the 1st 15min after PTCA, averaging 34.29 +/- 20.40%. In the group of patients whose balloon/artery relationship was < or = 1, the total ER was 0.90 +/- 0.74mm at 15min and 1.20 +/- 0.50mm when the ratio was > 1 (p < 0.0001). We noted that ER in the group of patients with residual stenosis ranging from 30 to 50% at the immediate angiogram after PTCA was greater than in the group whose residual stenosis was less than 30%. CONCLUSION: ER is a dynamic and progressive phenomenon taking place within the 1st 15 min after a successful PTCA. Total ER was 34.29 +/- 20.40% at 15min and was greater when balloon/artery relationship was > 1. Residual stenosis ranging from 30 to 50% in the control immediately after the procedure is a predictive factor of greater ER in the 15min following PTCA.

[Evaluation of ischemic preconditioning on collateral circulation, ventricular function and clinical outcome in acute myocardial infarction]. / Valor do precondicionamento isquêmico na circulação colateral, função ventricular e evolução clínica no infarto agudo do miocárdio.

PURPOSE: To evaluate the influence of ischemic preconditioning (IP) in collateral circulation (CC), early ventricular function and in hospital outcomes after myocardial infarction (MI). METHODS: We studied 97 patients with a 1st anterior MI within 6h of pain and isolated total proximal occlusion of the left anterior descending artery, divided in 2 groups: with (GA) or without (GB) angina before MI. Coronariography and ventriculography were performed prior to reperfusion. The left ventricular (LV) ejection fraction was measured by the area length method and anterior wall motion by the centerline method. RESULTS: There was no difference between the two groups in sex, age, CKMB level, treatment, reperfusion rate. Global LV ejection fraction and anterior wall motion were similar, respectively, 39 +/- 9% and -2.55 +/- 1.17 SD/chord for GA and 37 +/- 8% and -2.75 +/- 0.79 and -2.75 +/- 0.79 SD/chord for GB (p = ns). The incidence of visible CC to the infarct area was also similar (present in 6 GA vs 8 GB patients). However, GA patients fared significantly better during hospitalization: No GA patient presented Killip class > or = 2 compared to 8 GB patients (p = 0.007). CONCLUSION: Although collateral coronary circulation grades, global and regional LV function were similar between the two groups, the presence of angina pectoris preceding an acute myocardial infarction was associated with a better in hospital evolution, what could be partially explained by preconditioning phoenomena.

The Medicine, Angioplasty or Surgery Study (MASS): a prospective, randomized trial of medical therapy, balloon angioplasty or bypass surgery for single proximal left anterior descending artery stenoses.

OBJECTIVES: This study sought to evaluate, in a prospective and randomized trial, the relative efficacies of three possible therapeutic strategies for patients with a single severe proximal stenosis of the left anterior descending coronary artery and stable angina. BACKGROUND: Although percutaneous transluminal coronary angioplasty and coronary artery bypass surgery are often performed in patients with a single proximal stenosis of the left anterior descending coronary artery, it is unclear whether revascularization offers greater clinical benefit than medical therapy alone. METHODS: At a single center, 214 patients with stable angina, normal ventricular function and a proximal stenosis of the left anterior descending coronary artery > 80% were randomly assigned to undergo mammary bypass surgery (n = 70), balloon angioplasty (n = 72) or medical therapy alone (n = 72). Angioplasty had to be considered technically feasible in every case. The predefined primary study end point was the combined incidence of cardiac death, myocardial infarction or refractory angina requiring revascularization. RESULTS: At an average follow-up period of 3 years, a primary end point had occurred in only 2 patients (3%) assigned to bypass surgery compared with 17 assigned to angioplasty (24%) and 12 assigned to medical therapy (17%) (p = 0.0002, angioplasty vs. bypass surgery; p = 0.006, bypass surgery vs. medical treatment; p = 0.28, angioplasty vs. medical treatment, all by log-rank test). There was no difference in mortality or infarction rates among the groups. However, no patient allocated to bypass surgery needed revascularization, compared with eight and seven patients assigned, respectively, to coronary angioplasty and medical treatment (p = 0.019). Both revascularization techniques resulted in greater symptomatic relief and a lower incidence of ischemia on the treadmill test; however, all three strategies eventually resulted in the abolition of limiting angina. CONCLUSIONS: The more aggressive therapeutic approach with initial bypass surgery for patients with a single severe proximal stenosis of the left anterior descending coronary artery is associated with a lower incidence of medium-term adverse events than coronary angioplasty or medical treatment. However, all three strategies resulted in a similar incidence of death and infarction during an average follow-up period of 3 years. This information should be taken into consideration when physicians and patients make therapeutic choices in this setting.

Effect of megazol on Trypanosoma brucei brucei acute and subacute infections in Swiss mice.

Human African trypanosomiasis (HAT) or sleeping sickness is a major public health problem in 36 sub-Saharan African countries and is caused by Trypanosoma brucei gambiense and T. b. rhodesiense. About 25,000 new cases of the disease are reported annually, and around 50 million people are classed as at risk of contracting the disease. Until now; the only effective drug available for treatment of advanced HAT was the trypanocide melarsoprol. The mortality rate of melarsoprol treated patients is 1-5%. Megazol is a nitroimidazole derivative shown to be effective in vitro against T. b. brucei with an EC50 of 0.01 micrograms.ml-1. When this compound was tested for its in vivo activity in T. b. brucei infected Swiss mice, it was shown to cure the acute disease. However, megazol alone did not cause cure of mice carrying a subacute infection with involvement of the central nervous system (CNS). Combined suramin and megazol treatment did prove effective and the mice were shown to have remission without further relapse from the CNS. The study of three megazol derivatives is also described here. Substitution of a bromine, methyl or trifluoromethyl moiety at the 4 position of the imidazole ring abolished trypanocidal activity both in vivo and in vitro. Intermediates of megazol synthesis (imidazole sulfoxide and imidazole sulfone) were also tested, but were shown not to be active. It is thought that megazol trypanocidal effect may be due to the triggering of radical production by the compound, which have toxic effects on the trypanosomes metabolism. In depth study of megazol is needed to fully elucidate its pharmacokinetics and to precisely pin down its mode of action.

[Role of circumflex coronary artery involvement in non-Q wave myocardial infarction]. / Papel do acometimento da artéria coronária circunflexa no infarto do miocárdio sem onda Q.

PURPOSE: To determine the patency and incidence rates of left circumflex coronary artery (LCX) as the infarct related artery (IRA) in Q-wave and non-Q wave acute myocardial infarction (AMI). METHODS: Two-hundreds and twenty one patients (172 men) with AMI were stratified in Q and non-Q waves groups. All patients were submitted to cinecoronary angiography 72 hours after the beginning of symptoms and the IRA and its patency were evaluated. RESULTS: In non-Q wave AMI, the LCX was considered to be the IRA in 35% of the patients. In Q wave AMI, this incidence was 8% (p < 0.001). Occlusion of LCX was seen in all non-Q wave AMI patients when it was the IRA. CONCLUSION: The incidence of LCX as IRA was significantly higher in non-Q wave AMI patients. This group did not have the previously expected greater patency rates, what could result in different clinical and evolutive characteristics.

[Hospital outcome of patients with right ventricular infarction and the importance of right coronary artery patency]. / Evolução hospitalar de pacientes com infarto de ventrículo direito e a importância da perviabilidade da artéria coronária direita.

PURPOSE: To evaluate the importance of the right coronary artery (RCA) patency in patients with right ventricular infarction. METHODS: Fifty-two patients with inferior wall myocardial infarction and right ventricular involvement were studied and divided in two groups: group A (GA) included 35 patients in whom the RCA was patent at coronary angiography, and group B (GB), 17 who had an occluded RCA. They were prospectively evaluated for electrical and hemodynamic complications, as well as in-hospital mortality. RESULTS: The mortality in GA was 11% and 29% in GB, p = 0.13; electrical complications were 11% in GA and 35% in GB, p = 0.06; hemodynamic complications were 8% in GA and 41% in GB, p = 0.009. CONCLUSION: These findings suggest a trend towards reduction in mortality and electrical complications, and significant reduction of hemodynamic complications in patients with inferior wall myocardial infarction with involvement of the right ventricle who have the RCA patent. Thus, RCA patency appears to be important in determining in-hospital outcomes of these patients.

Consequences of altered aspartate aminotransferase activity on 13C-glutamate labelling by the tricarboxylic acid cycle in intact rat hearts.

The appearance of 13C label in glutamate has been used to quantify cellular tricarboxylic acid (TCA) cycle activity using 13C-NMR spectroscopy. Glutamate is linked to the TCA cycle by the amino-transferase reactions, however the consequences of alterations in amino-transferase activity on glutamate labelling kinetics, at a constant total tricarboxylic acid cycle activity, have not been investigated. Aspartate amino-transferase activity in [2-13C]acetate-perfused beating rat hearts was found to be similar to total TCA cycle flux in the presence of normal perfusion conditions and was reduced by more than 50% with the subsequent administration of amino-oxyacetic acid (AOA). AOA did not reduce contractile or kinetic measures of total TCA cycle flux, but did slow the 13C labelling of glutamate, in accord with current mathematical predictions. The impact of similar reductions in amino-transferase activity on estimates of total TCA cycle flux derived from several previously reported methods was also evaluated. Because total TCA cycle and the amino-transferase activities both affect the kinetics of 13C-glutamate labelling and because the amino-transferase activities are often unknown under physiologic conditions and can be reduced under pathologic conditions, the calculation of total TCA cycle flux from 13C-NMR data in the future is probably best accomplished either with a sufficiently sophisticated mathematical model that assesses amino-transferase activity or with an empiric model that is relatively insensitive to variations in amino-transferase activity.