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M Mendes

Publications and source records attributed to M Mendes.

At least 19 recordsLinked to original sources
PubMed2004

The steroidal aromatase inhibitor exemestane prevents bone loss in ovariectomized rats.

The irreversible steroidal aromatase inhibitor exemestane (EXE) is one of three third generation aromatase inhibitors currently prescribed for advanced breast cancer in postmenopausal women. Its principal mechanism of action is to reduce estrogen by inhibiting its synthesis. In addition to its efficacy against breast cancer, its effects on other organs are important, especially when given to women with good-prognosis breast cancer or potentially to healthy women at increased risk of developing breast cancer. The purpose of this study was to evaluate the effects of EXE on bone and lipid metabolism in ovariectomized (OVX) rats. Ten-month-old Sprague-Dawley female rats were sorted into intact controls, intact + EXE, OVX controls, and OVX + EXE groups, and treated by weekly intramuscular injection with vehicle or 100 mg/kg EXE for 16 weeks. The bone mineral density (BMD), mechanical testing, histomorphometry, bone resorption marker-serum pyridinoline (PYD), and bone formation marker-serum osteocalcin (OC) were used to determine the effects of treatment on bone. In addition, total serum cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were determined. BMD of the lumbar spine and femur were 11% and 7%, respectively, higher in OVX animals given EXE than in OVX controls (all Ps<0.001). Significant increases in the bending strength and toughness of the femora as well as the compressive strength and elastic modulus of the vertebrae were observed in OVX rats given EXE (all Ps<0.02 vs. OVX controls). Trabecular bone volume (BV) was significantly higher in OVX rats treated with EXE than in OVX controls (P<0.0001). In OVX animals, EXE reduced the OVX-induced increase of serum PYD by 96% (P<0.0001), and the OVX-induced increase of serum OC was completely prevented by treatment with EXE. In OVX animals, EXE resulted in a 28% reduction of serum cholesterol (P<0.0001) and reduced LDL by 64% compared with OVX controls (P<0.0001). The positive results of EXE on bone and lipid metabolism in the OVX rat model merit further investigation of the effects of EXE in postmenopausal women.

Androstadienes↗
PubMed2003

Secondary prevention through cardiac rehabilitation: position paper of the Working Group on Cardiac Rehabilitation and Exercise Physiology of the European Society of Cardiology.

The purpose of this statement is to provide specific recommendations in regard to evaluation and intervention in each of the core components of cardiac rehabilitation (CR) to assist CR staff in the design and development of their programmes; the statement should also assist health care providers, insurers, policy makers and consumers in the recognition of the comprehensive nature of such programmes. Those charged with responsibility for secondary prevention of cardiovascular disease, whether at European, at national or at individual centre level, need to consider where and how structured programmes of CR can be delivered to the large constituency of patients now considered eligible for CR.

Europe↗
PubMed2003

Physical activity for primary and secondary prevention. Position paper of the Working Group on Cardiac Rehabilitation and Exercise Physiology of the European Society of Cardiology.

There is now clear scientific evidence linking regular aerobic physical activity to a significant cardiovascular risk reduction, and a sedentary lifestyle is currently considered one of the five major risk factors for cardiovascular disease. In the European Union, available data seem to indicate that less than 50% of the citizens are involved in regular aerobic leisure-time and/or occupational physical activity, and that the observed increasing prevalence of obesity is associated with a sedentary lifestyle. It seems reasonable therefore to provide institutions, health services, and individuals with information able to implement effective strategies for the adoption of a physically active lifestyle and for helping people to effectively incorporate physical activity into their daily life both in the primary and the secondary prevention settings. This paper summarizes the available scientific evidence dealing with the relationship between physical activity and cardiovascular health in primary and secondary prevention, and focuses on the preventive effects of aerobic physical activity, whose health benefits have been extensively documented.

Cardiovascular Diseases↗
PubMed2002

Current role of simplified upper tract approach in the surgical treatment of ectopic ureteroceles: a single centre's experience.

OBJECTIVE: Despite renewed interest in either endoscopic decompression or complete reconstruction as primary approaches in ectopic ureterocele's (EU's) treatment, we advocate that a simplified upper tract approach is an optimal choice in a large subset of these patients. We review our surgical results to evaluate the effectiveness of different surgical procedures used in the treatment of EU, based on an individualized approach. PATIENTS AND METHODS: We retrospectively analysed all patients with EU and without previous treatment (n = 59) operated in this centre between the years 1991 and 2000. This disorder was bilateral in three patients (62 EU) and associated with duplex ureters in 60 cases. Vesicoureteral reflux (VUR) was diagnosed pre-operatively in 49.1% of patients. Treatment and choice of procedure was based on patients' age, clinical manifestations, associated abnormalities and function of the ureterocele-bearing moiety. Patients were divided in three separate groups according to the initial surgical approach. Group 1-11 patients submitted to endoscopic puncture (six urgent ureterocele decompression, four infants with obstruction of a functional ureterocele-bearing moiety and another with both lower pole ureter and mild bladder outflow obstruction). Group 2-30 patients (31 EU) submitted to a simplified upper tract approach--pyeloureterostomy (1), heminephrectomy (29) and nephrectomy (1) (all patients but one with non-viable renal segments; VUR, grade < or = III, present in six cases). Group 3-18 patients (20 EU) submitted to complete primary reconstruction (all patients with high-grade and/or contralateral reflux, with or without function of the ureterocele-bearing moiety). Success (clinically asymptomatic patients, without obstruction or VUR) and complication rates from the different approaches were analysed. For statistical evaluation, we used Fisher's exact test with p < or = 0.05 considered significant. RESULTS: The success rate of endoscopic treatment, simplified upper tract approach and complete reconstruction were 18.2%, 80% and 83.3%, respectively. Major complications occurred in two patients from group 3. CONCLUSION: Endoscopic puncture is our first option when immediate ureterocele decompression is required, although it seldom affords definitive treatment. Complete primary reconstruction is necessary in complex cases. Cure rates are high but there is a potential risk for serious complications. A simplified upper tract approach is curative in most patients without associated reflux. Heminephrectomy remains our first choice in a large subset of patients with non-viable or hypofunctional renal segments and without high-grade reflux.

Case-Control Studies↗
PubMed2001

National survey of cardiac rehabilitation programs in Portugal--situation in 1999.

In order to study the status of Cardiac Rehabilitation (CR) in Portugal in 1998 and 1999, a questionnaire was drafted and sent to all the heads of the CR centres in Portugal, with questions about their nature, location, staff, type of activity, movement, diagnosis leading to patient referral and funding. The rate of coronary patients admitted to the programs existing in the cities of Lisbon and Oporto was calculated. The total number of patients included in all the CR centres in both cities was subtracted from the total number of public hospital discharges of coronary patients in 1998, patients admitted due to acute ischaemic coronary syndrome or for revascularization in Portugal and in each of the two cities. We found that there were CR centres in only the two main cities (Lisbon and Oporto), with organization and types of activity in accordance with international guidelines and recommendations. The overall admission rate of coronary patients in Portugal in 1998 was 0.7%, with 0.9% and 1.9% in Lisbon and Oporto, respectively. These rates are well below the figures for countries of the European Union and for the USA. It is very important to increase the establishment and spread of CR centres throughout the country, creating the financial conditions and promoting a change in culture regarding physical activity and CR on the part of the Portuguese population, patients and health care providers responsible for the referral of cardiac patients to a therapeutic intervention that can increase quality of life and longevity. Doctors should be involved in programs that will train them to recognize the benefits of physical activity and secondary prevention.

Heart Diseases↗
PubMed1999

The vascularized pig fibula bone flap model: effects of multiple segmental osteotomies on growth and viability.

Previous work by this laboratory introduced the pig fibula bone flap as a model for the study of the pathophysiology of vascularized bone flaps. Anatomic and hemodynamic studies demonstrated a significant (p < 0.05) decrease in vascular perfusion after a series of segmental osteotomies and rigid fixation (lag screws and miniplates) in the distal end of the flap, suggesting that blood flow to the distal osteotomized segment of the flap may be impaired. Killing the animals after blood flow studies precluded assessment of the effect of these hemodynamic changes on bone healing. Therefore, the aim of this study was to assess the pig fibula bone flap model with respect to viability, healing, and subsequent growth after multiple segmental osteotomies and rigid fixation to contribute to the understanding of vascularized bone flap pathophysiology. Yorkshire pigs (20 to 25 kg) were used for all experiments. Eight pigs underwent unilateral elevation of a vascularized fibula bone flap, which was osteotomized into three segments and orthotopically rigidly fixed using a 2.4-mm mandibular reconstruction plate. The left fibula remained as the control. Fluorochrome labels were injected to assess bone viability and turnover, and both fibulae were assessed for growth radiologically. The fibulae were harvested 21 days postoperatively (when the animals were killed), and bone healing was assessed histologically and clinically. There were no significant differences in preoperative and postoperative lengths of the osteotomized fibulae compared with the controls, suggesting that there was no impairment of growth potential after multiple segmental osteotomies and rigid fixation. Significant (p < 0.05) bony hypertrophy of the osteotomized fibulae was noted when compared with controls. Mobility was observed in 3 of the 32 osteotomies (9 percent), occurring across one proximal and two distal osteotomies in association with failure of fixation. However, histologic and fluorochrome assessment confirmed the viability of all bone segments, as supported by the presence of tetracycline given 2 days postoperatively. The pig fibula bone flap model is well tolerated by the pig. Multiple segmental osteotomies and rigid fixation, previously associated with a significant decrease in blood flow in the distal segment, did not impair either growth potential, viability, or healing ability. It is suggested that the pig fibula is a suitable model for the study of bone flap pathophysiology.

Animals↗
PubMed1999

[The Brugada syndrome--a clinical case].

A case report of a patient with syncope and family history of sudden death is presented. The precordial recordings in the standard 12-lead ECG showed a right bundle-branch block pattern with persistent ST elevation in V1 and V2-V3. After a thorough evaluation, we found no underlying organic cardiomyopathy. The diagnosis of symptomatic Brugada syndrome was made. A cardioverter-defibrillator was implanted.

Bundle-Branch Block↗
PubMed1999

Relationship between radionuclide right ventricular ejection fraction and clinical status in patients with left ventricular dysfunction after myocardial infarction.

OBJECTIVE: To evaluate the influence of right ventricular (RV) function, determined by RV ejection fraction, on the clinical status of patients with ischemic heart disease and left ventricular (LV) EF under 40%. BACKGROUND: The role of RV function as a marker of prognosis in heart failure has been debated. We hypothesized that the degree of RV dysfunction is a determinant of the clinical status and outcome of patients with LV dysfunction after myocardial infarction. PATIENTS AND METHODS: 30 patients, 25 male, with previous myocardial infarction, more than 6 months age, were studied by equilibrium radionuclide angiography. Functional capacity was evaluated by cardiopulmonary exercise test with Naughton protocol. Patients were followed during a 12 month period for major clinical events: death or hospitalisation for congestive heart failure. Two groups of patients were considered according the value of RVEF (< or = 30% and > 30%). RESULTS: The values of EF were: LV = 25 +/- 7% and RV = 35 +/- 9%. Maximum oxygen consumption correlated with RVEF (r = 0.78, p < 0.001) but not with LVEF (r = 0.12, NS). The group of patients with RVEF > 30% had a greater exercise time (712 +/- 229 versus 441 +/- 208 seconds, p = 0.003), higher oxygen consumption (19.8 +/- 5.3 versus 13.5 +/- 3.3 ml/kg/min, p = 0.001) and oxygen consumption in relation to the maximum predicted for age and sex (71 +/- 19 versus 50 +/- 13%, p = 0.002). Cumulative frequency of major clinical events was greater in the group with RVEF < or = 30% (58% vs 6%, relative risk 3.14, 95% CI 1.23 to 5.05). There was no correlation between the values of LVEF and outcome. CONCLUSIONS: In this setting of ischemic LV dysfunction, the RVEF correlates with functional capacity in cardio-pulmonary exercise test and the presence of RV dysfunction is associated to a higher incidence of clinical events.

Adult↗
PubMed1998

Opioid involvement in behavior modifications of mice infected with the parasitic nematode, Nippostrongylus brasiliensis.

Several studies have documented the opiate effects of parasitic infection on experimental animals. The current study examined the relationships between infection with the intestinal nematode, Nippostrongylus brasiliensis with analgesia and activity levels. Male white mice infected with N. brasiliensis displayed a significant increase in thermal latency thresholds that rose through the duration of infection and subsided with its termination. Analgesia first became apparent on day three-post infection but did not reach statistical significance (p < 0.05) until day 7 post infection. The maximum analgesia was reached on day 8-post infection and gradually declined. By day 15 post infection, there was no significant difference in the latency times between control and infected mice. The initial significant difference in latency roughly corresponded with the onset of egg production by the parasite. The peak difference in latency times and their subsequent decline also parallels peak egg production and the decline in egg production as the infection subsided. Both naloxone and naltrindole significantly reduced the latency times (p < 0.05) of infected mice. There was also a significant difference in total ambulatory activity levels between infected and control mice. Activity levels began to decline on the second day post infection but did not reach a statistically significant difference (p < 0.05) from the controls until 9th day post infection. Infected mice that were injected with either naloxone or naltrindole had a significantly higher activity level than the infected mice injected with saline.

Animals↗
PubMed1998

[Value of exercise test for risk stratification acute myocardial infarction].

OBJECTIVES: To assess the prognostic value of predischarge exercise testing (ET) in patients hospitalized for acute myocardial infarction (AMI). CONTEXT: Department of Cardiology in a reference hospital for Interventional Cardiology METHODS: Between January 1990 and December 1994, 178 patients hospitalized for AMI were discharged and referred to the outpatient clinic (mean follow up, 1049 +/- 612 days). Eighty-two percent of these patients were men, mean age--56 +/- 12 years. Patients that did not perform predischarge ET (Group A, n 77) were retrospectively compared with those who did (Group B, n = 101). In relation to demographic and clinical characteristics; we analysed cardiac events (CE) and death during the first 18 months after discharge in both groups. In group B patients, we studied the relation of ET parameters (duration of exercise, occurrence of exercise-induced ischaemia and arrhythmias, maximum heart rate, blood pressure response, rate pressure product and severity score) to CE and death during the first 18 months after AMI. RESULTS: The proportion of patients aged 70 years or older was greater in group A (23% vs 3%, P < 0.001). In this group, there was a greater prevalence of recurrent ischaemia (51% vs 29%, P < 0.001) and left ventricular dysfunction (42% vs 25%, P < 0.05). Group A patients were also submitted to less thrombolysis (45% vs 62%, P < 0.05) and to revascularization procedures (25% vs 41%, P < 0.05). In group B patients, the incidence of CE did not differ with respect to duration of ET, rate pressure product or maximum heart rate. Incidence of CE was greater in patients with exercise-induced ischaemia (38% vs 15%, P < 0.05), severity score > 2 (45% vs 18%, P < 0.02) and inadequate rise (< 30 mmHg) in systolic blood pressure (39% vs 13%, P < 0.02). The total incidence of CE and revascularization was also greater in patients with exercise-induced ischaemia (88% vs 49%, P < 0.001), severity score > 2 (95% vs 56%, P < 0.02) and inadequate rise in systolic blood pressure (93% vs 45%, P < 0.001). CONCLUSIONS: In patients without indication for ET as part of risk stratification after AMI, clinical characteristics were more severe as defined by age greater than 70 years, residual ischaemia and left ventricular dysfunction. Patients that performed ET had smaller risk, except when presenting exercise-induced ischaemia, severity score > 2 and inadequate rise in systolic blood pressure.

Adult↗
PubMed1997

Double-blind randomized placebo-controlled trial of the use of granulocyte-macrophage colony-stimulating factor in chronic leg ulcers.

BACKGROUND: Following encouraging reports on the use of granulocyte-macrophage colony-stimulating factor (GM-CSF) to treat wounds in animals and in man, we conducted a study to test the usefulness of this drug in patients with chronic leg ulcers. METHODS: Patients received a single perilesional injection of GM-CSF, the effect of which was observed weekly and compared with that of a placebo injection in a control group. RESULTS: Treated patients fared much better than controls, prompting an early termination of the study: of 16 GM-CSF treated patients, 3 (19%) had their ulcers healed by week 1; 8 (50%) were healed by week 8; only 1 of 9 controls had the ulcer healed by week 1 (11%), and that was the only ulcer of the group that healed at all. We observed no significant side effects or changes in the hematological and biochemical parameters studied. CONCLUSION: GM-CSF seems a very useful drug for the healing of leg ulcers.

Adolescent↗
PubMed1996

[The maximum heart rate in the exercise test: the 220-age formula or Sheffield's table?].

OBJECTIVE: To determine in the maximum cardiac rate in exercise test of apparently healthy individuals may be more properly estimated through 220-age formula (Astrand) or the Sheffield table. DESIGN: Retrospective analysis of clinical history and exercises test of apparently healthy individuals submitted to cardiac check-up. PARTICIPANTS: Sequential sampling of 170 healthy individuals submitted to cardiac check-up between April 1988 and September 1992. MATERIAL AND METHODS: Comparison of maximum cardiac rate of individuals studied by the protocols of Bruce and modified Bruce, in interrupted exercise test by fatigue, and with the estimated values by the formulae: 220-age versus Sheffield table. RESULTS: The maximum cardiac heart rate is similar with both protocols. This parameter in normal individuals is better predicted by the 220-age formula. CONCLUSIONS: The theoretic maximum cardiac heart rate determined by 220-age formula should be recommended for a healthy, and for this reason the Sheffield table has been excluded from our clinical practice.

Adult↗
PubMed1996

[Exertion syncopal crisis in the young, associated with idiopathic long QT syndrome].

The cases of two young patients with repetitive syncopal attacks due to idiopathic long QT syndrome (ILQTS) are reported. Both had been primarily misdiagnosed for seizures. In one of the cases the QT interval in the ECG at rest was normal. The same patient had a previous episode of cardiac arrest with ventricular fibrillation. The treadmill stress test was of great value, revealing polymorphic ventricular tachycardia induced by exercise, and evaluating the efficacy of beta-blocking therapy in the follow-up. The ILQTS should be considered a possible etiology in any patient presenting with new onset seizures, especially in the young. The treatments were different in both cases. In the first one, the treatment with nadolol (100 mg od) revealed to be very effective with total remission of symptoms. The treadmill stress test performed 15 days after the beginning of treatment did not show any ventricular arrhythmias, and it was assumed that the patient was effectively protected against ventricular arrhythmias. After 4.5 months of follow up, no syncopal episodes occurred. In the second case due to young age, the frequency, and the severity of the attacks (cardiac arrest with ventricular fibrillation), and the inefficacy of beta-adrenergic-blocking agents, the implantable cardioversor-defibrillator was the treatment chosen, although the beta blocking therapy was maintained to reduce the number of arrhythmic events. The ILQTS is a rare anomaly related to sudden cardiac death. The ILQTS is characterised by the association of several distinctive electrocardiographic features, among which prolongation of the QT interval is the best known. Life-threatening arrhythmia occurs usually under conditions of physical or psychological stress. Relatively effective therapies do exist and are represented by antiadrenergic interventions: beta-adrenergic-blocking agents are the treatment of choice. When they fail, left sympathetic denervation or the automatic implantable cardioversor-defibrillator have also proved to be effective.

Adult↗
PubMed1996

[Modification of the lipid profile in coronary patients undergoing cardiac rehabilitation].

To assess the effect of continuous and controlled exercise training on the lipid profile of coronary pts. in a cardiac rehabilitation program, we evaluated forty-nine males aged 56.8 +/- 9.6 years, thirty-two with previous surgical myocardial revascularization, two submitted to percutaneous transluminal coronary angioplasty and fifteen on exclusive pharmacological therapy. Patients with changes in drugs that could potentially induce modifications in serum lipid values, were excluded. The values of total cholesterol, triglycerides, HDL-cholesterol, the HDL-cholesterol/total cholesterol ratio, weight and the body mass index at admission of training phase, end of training phase (III)-21 patients (Group I) and maintenance (IV)-28 patients (Group II), were assessed. The training phase (III) had a duration of 3-4 months and maintenance (IV) nine months. In Group I, evaluated at the end of the training period (phase III), there was no significant modification in lipid profile reduction; only 1% and 20% reduction (p = NS) in values of total cholesterol and triglycerides, was detected. The HDL-cholesterol rose 12.5% (p = NS), and the HDL cholesterol/total cholesterol ratio 10.5% (p = NS). In Group II (at the end of the maintenance phase-IV-) there was no important change in total cholesterol levels. The HDL-cholesterol rose 19.5% (p = 0.003) and the HDL-cholesterol/total cholesterol ratio, also increased 33.3% (p < 0.0001). The benefit in relation to triglycerides was restricted to patients with higher values (> 200 mg/dl), where a reduction of 36% (p = 0.004) was found. There was no change in the weight or in body mass index, induced by the program. We concluded that the participation in a cardiac rehabilitation program induces a favourable modification of lipid profile in our population, with potential interest for secondary prevention of coronary heart disease. This change was particularly in serum values of triglycerides, HDL-cholesterol and the ratio HDL-cholesterol/total cholesterol. In what concerns triglycerides, the benefits were seen only in the group of patients with the highest serum values.

Adult↗