Raman spectroscopy for classification of neoplastic and non-neoplastic CAM colon tumors.

This paper demonstrates the potential of Raman spectroscopy for differentiating neoplastic from non-neoplastic colon tumors, obtained with the CAM (chicken chorioallantoic membrane) model. For the CAM model two human cell lines were used to generate two types of tumors, the RKO cell line for neoplastic colon tumors and the NCM460 cell line for non-neoplastic colon tumors. The Raman spectra were acquired with a 785 nm excitation laser. The measured Raman spectra from the CAM samples (n = 14) were processed with several methods for baseline correction and to remove artifacts. The corrected spectra were analyzed with PCA (principal component analysis). Additionally, machine learning based algorithms were used to create a model capable of classifying neoplastic and non-neoplastic tumors. The principal component scores showed a clear differentiation between neoplastic and non-neoplastic colon tumors. The classification model had an accuracy of 93 %. Thus, a complete methodology to process and analyze Raman spectra was validated, using a rapid, accessible, and well-established tumor model that mimics the human tumor pathology with minor ethical concerns.

Highly-selective optical filter for NADH fluorescence detection in multiphoton microscopy.

Colorectal cancer (CRC) is a pressing global health concern, emphasizing the need for early detection tools. In this study an optical filter for precise detection of nicotinamide adenine dinucleotide (NADH) fluorescence via two-photon excitation fluorescence (TPEF) was developed. Fabricated with silicon dioxide and titanium dioxide thin films in a Fabry-Perot structure, the filter achieved a peak transmittance of about 95% at 483 nm, with a 12 nm full-width at half maximum. TPEF measurements using a tailored setup and NADH liquid phantoms underscored the filter's significance in selectively capturing NADH fluorescence while mitigating interference from other fluorophores. This work marks a substantial stride towards integrating multiphoton microscopy into conventional colonoscopy, enabling non-invasive, objective optical biopsy for colorectal tissue analysis. Further refinements of the experimental setup are imperative to advance tissue differentiation and enhance CRC diagnosis.

Infectious thoracic aortitis: a literature review.

Infectious thoracic aortitis (IA) remains a rare disease, especially after the appearance of antibiotics. However, if left untreated it is always lethal. It usually affects patients with atherosclerotic aortic disease and/or infective endocarditis. Mycotic aneurysm is the most common form of presentation, although a few reports of nonaneurysmal infectious thoracic aortitis have also been described. Various microorganisms have been associated with infectious thoracic aortitis, most commonly Staphylococcal, Enterococcus, Streptococcus, and Salmonella species. It is extremely important to establish an early diagnosis of IA, because this condition is potentially life-threatening. However, diagnosis is frequently delayed since clinical manifestations are usually nonspecific. Antibiotherapy in combination with complete surgical excision of the infected aorta is the best choice of treatment.

Clinical significance of brain natriuretic peptide in patients with postmyocardial infarction.

BACKGROUND: Risk stratification after acute myocardial infarction (AMI) includes the evaluation of left ventricular (LV) function. Natriuretic peptides, and particularly brain natriuretic peptide (BNP), emerged as a potential marker of ventricular function and prognosis after AMI. HYPOTHESIS: Brain natriuretic peptide levels are related to ventricular function, either systolic or isolated diastolic, and can give prognostic information in patients surviving AMI. METHODS: In all, 101 patients were enrolled. An echocardiographic (M-mode, two-dimensional, and pulsed Doppler) evaluation was performed and blood samples for BNP measurement were obtained. Clinical events were recorded during 12 months of follow-up. RESULTS: A negative correlation between BNP and LV ejection fraction was observed (r = -0.38; p < 0.001). The BNP levels were higher among patients with LV systolic dysfunction than in patients with isolated diastolic dysfunction (339.1 +/- 249.9 vs. 168.0 +/- 110.5 pg/ml, p = 0.001). The latter had higher levels of BNP than those with normal LV function (68.3 +/- 72.6 pg/ml, p < 0.001). The BNP accuracy to detect LV systolic dysfunction was good (area under the ROC curve [AUC] = 0.83) and increased when isolated diastolic dysfunction was also considered (AUC = 0.87). Brain natriuretic peptide had a very good accuracy in the prediction of death (AUC = 0.95) and the development of heart failure (AUC = 0.90). CONCLUSION: These results extend previous evidence relating BNP to systolic function after AMI. Furthermore, a relationship between BNP levels and diastolic function was found. Brain natriuretic peptide had a very good performance in detecting the occurrence of an adverse event. We conclude that BNP can detect high-risk patients and help select patients for more aggressive approaches.

Renal synthesis of dopamine in asymptomatic post-infarction left ventricular systolic dysfunction.

Left ventricular systolic dysfunction (LVSD) following acute myocardial infarction (AMI), by decreasing renal blood flow, may interfere with renal L-DOPA availability and, consequently, dopamine synthesis. Dopamine of renal origin exerts local natriuretic effects. We studied 17 post-AMI patients with asymptomatic LVSD (ejection fraction < 40%) and 14 without (ejection fraction > or = 40%), measuring 24-h urinary excretions of L-DOPA, dopamine and its metabolites, and plasma levels of the amines, amine derivatives and type-B natriuretic peptide (BNP). Baseline characteristics were well balanced between the two groups. No differences were observed in urinary volume and sodium and creatinine excretions. The group with asymptomatic LVSD presented lower urinary excretion of L-DOPA (66.8 +/- 10.1 versus 115.3 +/- 21.9 nmol x day(-1), P = 0.04), whereas plasma levels of L-DOPA were identical in both groups. Urinary dopamine was similar in the two groups (1124.2 +/- 172.4 versus 1049.0 +/- 146.4 nmol x day(-1), P = 0.86), resulting in higher urinary dopamine/L-DOPA ratios in patients with asymptomatic LVSD (20.4 +/- 3.0 versus 9.9 +/- 0.8, P < 0.001). Plasma levels of BNP were higher in the asymptomatic LVSD group (348.5 +/- 47.3 versus 146.8 +/- 21.9 microg x ml(-1), P = 0.003). Ejection fraction was negatively correlated with both plasma levels of BNP and urinary dopamine/L-DOPA ratios. Renal dopamine production is well preserved in patients with asymptomatic LVSD and increased neurohumoral activation, despite reduced urinary excretion of its precursor. This suggests that renal uptake and/or decarboxylation of L-DOPA is enhanced in this condition, as a compensatory mechanism, contributing to preservation of urinary sodium excretion.

Acute myocardial infarction: psychosocial and cardiovascular risk factors in men.

BACKGROUND: Controversy still exists over the independent role of psychosocial factors in acute myocardial infarction (AMI). This study aimed to compare psychometric indices in Portuguese patients surviving a first episode of AMI and a community sample free of AMI. DESIGN: A community-based, case-control study. The study sample included 153 male patients with a first episode of AMI and 156 male controls randomly selected from the community. METHODS: Information on demographic, social, medical and behavioural characteristics was obtained using a structured questionnaire; anthropometric, blood pressure, and serum measurements were performed, and the psychometric evaluation was obtained using a self-evaluation questionnaires (Bortner scale, Beck Depression Inventory, SCL-90-R, Psychological General Well-Being and the Nottingham Health Profile). RESULTS: Cases of AMI more often exhibited type A behaviour (15.4 +/- 3.0 versus 14.7 +/- 2.7, P = 0.041), had more depressive symptoms (10.8 +/- 8.0 versus 8.6 +/- 8.0, P = 0.005) and showed worse scores on general well-being (68.4 +/- 17.7 versus 76.6 +/- 16.2, P < 0.001) than controls. Cases were significantly different from controls in terms of years of education (6.7 +/- 4.4 versus 9.0 +/- 4.7 years, P < 0.001), hypertension (43.1% versus 30.1%, P = 0.024), dislipidaemia (43.8% versus 34.0%, P = 0.038), type I obesity (53.6% versus 42.3%, P = 0.045), smoking (54.1% versus 26.5%, P < 0.001), no practise of exercise (68.5% versus 50.3%, P = 0.002) and presence of non-insulin-dependent diabetics (16.3% versus 6.4%, P = 0.010). After adjusting for such factors a similar set of significant psychometric results was found. CONCLUSION: Type A behaviour, depression and lower levels of well-being and quality of life, independent of other cardiovascular risk factors, were significant features of AMI cases.

Genetic risk factors in acute coronary disease.

OBJECTIVE: We investigate whether each of the following: HPA-1, Factor V Leiden, prothrombin gene variant and the methylene tetrahydrofolate reductase gene (MTHFR) mutation, are risk factors for acute coronary disease in Portuguese patients. MATERIAL AND METHODS: 100 blood donors and 52 patients with an established diagnosis of myocardial infarction or unstable angina were evaluated for genetic risk factors, by determining HPA-1 genotype, Factor V Leiden, Prothrombin 20210 variant and MTHFR mutation. RESULTS: We found a prevalence of 2.0% for Factor V Leiden, 5.0% for the Prothrombin 20210 variant and 66% for the MTHFR mutation in blood donors. These values are similar to those found in the patients (1.9, 3.8 and 58%, respectively). We found that 28/100 controls had the PI(A2) polymorphism, a frequency statistically different from that in the patients (23/52). This difference was even more pronounced in patients less than 60 years old (27/96 vs. 13/24). CONCLUSION: Factor V Leiden, Prothrombin 20210 variant and MTHFR mutation do not seem to represent risk factors for acute coronary disease. However, the PI(A2) polymorphism could have a role in the pathogenesis of this disease. The presence of multiple genetic factors, more than single ones, could influence the development and outcome of myocardial infarction and unstable angina. Larger studies are needed in order to have a better insight into the pathophysiological mechanisms of this disease, along with its prevention and the development of new treatments.

[Diet and risk of myocardial infarction. A case-control community-based study]. / Alimentação e Risco de Enfarte do Miocárdio. Um estudo caso-controlo de base comunitária.

OBJECTIVE: To evaluate diet as a risk factor for myocardial infarction. DESIGN: Community based case-control study. SETTING: University Hospital, Oporto. PARTICIPANTS: First time consecutive cases of acute myocardial infarction (n = 100) and 198 community controls, older than 39 years and living in Oporto, were compared. METHODS: Data were collected by trained interviewers using a structured questionnaire designed to obtain information on socio-demographic, medical and behavioural aspects, emphasising the description of diet and food habits (using a semi-quantitative food frequency questionnaire). Controls were selected by random digit dialing with a participation rate of 70%. Odds ratios and 95% confidence intervals (CI) according to quartiles of nutrient ingestion were calculated using unconditional logistic regression. RESULTS: Female controls presented significantly higher mean intakes of protein, omega-3 fatty acids, fiber, cholesterol and vitamin C. Male controls had a significantly higher mean daily intake of fiber, vitamin C, vitamin E, and carotenes. After adjusting for age, sex, education, body mass index, ethanol, smoking and total energy intake, there was a protective effect of vitamin C (OR = 0.2, 95% CI: 0.1-0.6, for the 4th quartile), vitamin E (OR = 0.3, 95% CI: 0.1-0.9 for the 4th quartile) and total fiber (OR = 0.3, 95% CI: 0.1-0.9) for the 4th quartile). No significant effect was found for trans-fatty acids, but there was a higher risk with increased energy intake. CONCLUSIONS: This study showed that diet has an important independent effect on myocardial infarction, a protective independent role for anti-oxidant vitamin C and E was verified.

[The clustering of cardiovascular risk factors in the urban population of Porto]. / Agregação dos factores de risco cardiovascular numa população urbana do Porto.

The aim of the study was to assess the total prevalence of obesity, non-insulin-dependent diabetes mellitus (NIDDM), hypertension, hypertriglyceridemia, hypercholesterolemia and central fat distribution, in a population-based survey. Two-hundred and ten individuals from the community were selected by random digit dialing. Obesity was defined as a body mass index > or = 25 kg/m2, central distribution of fat if the waist-to-hip ratio > 0.80 in women and 1.0 in men, diabetes was diagnosed if fasting plasma glucose levels > or = 140 mg/dl and/or currently under treatment, hypertension was defined as a systolic blood pressure > or = 140 mm Hg and/or diastolic blood pressure > 90 mm Hg and/or currently taking antihypertensive medications, hypertriglyceridemia was defined as a fasting serum triglyceride concentration > or = 200 mg/kg and hypercholesterolemia as a fasting serum cholesterol level > or = 200 mg/dl and/or currently taking specific medication. Prevalence rates of obesity, NIDDM, hypertension, hypertriglyceridemia, hypercholesterolemia and central fat distribution were 54.3%, 8.0%, 60.0%, 13.9%, 67.0% and 46.7% respectively. The prevalence of each of these conditions in its isolated form was 2.8% for obesity, 0.0% for diabetes, 3.8% for hypertension, 0.5% for hypertriglyceridaemia, 12.0% for hypercholesterolemia and 0.1% for the central fat distribution pattern. The large differences in prevalence between isolated and combined forms in the six disorders analyzed indicate a great overlap between these cardiovascular risk factors, and give epidemiologic support to a proposed metabolic syndrome.

[Prevalence, knowledge, treatment and control of arterial hypertension in Oporto, Portugal]. / Prevalência, conhecimento, tratamento e controlo da hipertensão arterial no Porto, Portugal.

The aim of this study was to assess the prevalence, awareness, treatment and control of hypertension among subjects above the age of 39 years living in the urban area of Oporto, Portugal. One hundred and seventy seven individuals from the community were selected by random digit dialing. Each subject was asked about his/her personal history of hypertension, antihypertensive treatment and had his/her blood pressure measured. The prevalence of hypertension was 57.1%, defined by systolic blood pressure (SBP) > or = 140 mm Hg and/or diastolic blood pressure (DBP) > or = 90 mm Hg and/or administration of current the antihypertensive medication. If the values defining hypertension were SBP > or = 160 mm Hg, and DBP > or = 95 mm Hg the prevalence would be 37.9%. The overall prevalence of hypertension was higher in females, but a slightly higher non significant value was found in males in the fifth and sixth decades. Among hypertensives, 62.7% were aware of their condition, 56.7% were treated, 84.2% of hypertensives treated were controlled (SBP < 160 mm Hg and DBP < 95 mm Hg) and 44.7% were very well controlled (SBP < 140 mm Hg and DBP < 90 mm Hg). The question "Are you hypertensive?" had a sensitivity of 62.7%, a specificity of 83.6% and an accuracy of 75.7%. In the preliminary results of this study of an urban population with a high prevalence of hypertension, the awareness of hypertension is similar to that described in the United States of America twenty years ago, the percentage of hypertensives treated is similar to the American percentage fifteen years ago and the percentage of hypertensives treated and controlled is close to the current American percentage.

[Risk factors for myocardial infarct: a case-control study in Oporto, Portugal]. / Factores de risco de enfarte do miocárdio: um estudo caso-controlo no Porto, Portugal.

A case-control study of coronary heart disease (CHD) was conducted in Oporto, Portugal. The cases series consisted of 100 consecutive patients with first time acute myocardial infarction who were admitted to the Coronary and Intermediate Care Units of a major teaching hospital. The community controls were 198 individuals without evidence of CHD by the Rose questionnaire and electrocardiography, selected by random digit dialing, with a participation rate of 70%. Data was collected by trained interviewers using a structured questionnaire and blood samples were obtained for selected laboratory data. The main analysis was made through unconditional logistic regression with calculations of odds ratios (OR). Age, OR: 1.5 (95% CI: 0.8-2.9), male gender, OR: 6.7 (3.6-12.3), family history of premature CHD, OR: 2.4 (1.4-4.3), diabetes, OR: 3.4 (1.6-7.4), antecedents of hypertension, OR:1.9 (1.1-3.1), history of high cholesterol levels, OR: 2.3 (1.4-3.9), high levels of physical activity, OR: 2.0 (0.9-4.1) and tobacco smoking, OR: 8.3 (3.8-18.5) were significant risk factors of acute myocardial infarction. After controlling for demographic variables and for the mutual confounding effects of the risk factors, the investigated factors that remained significantly associated with the risk of developing acute myocardial infarction were male gender, OR: 17.3 (4.8-62.3), family history of CHD, OR: 3.6 (1.4-9.6), diabetes, OR: 4.2 (1.0-18.1), high cholesterol levels OR: 2.7 (1.2-6.1) and smoking habits, OR: 7.7 (1.8-32.4). A negative association with high education levels was significant after controlling for all the variables, OR: 0.01 (0.01-0.5).

[Pharmacologic treatment of acute myocardial infarction: 2 large clinical trials at a central hospital]. / Terapêutica farmacológica do enfarte agudo do miocárdio: dos grandes ensaios à prática clínica num hospital central.

OBJECTIVES: To analyse the clinical practice concerning the pharmacological therapy of acute myocardial infarction (AMI), comparing it with the guidelines for the management of AMI and exploring the reasons for its under use or over use. METHODS: Retrospective analysis of clinical records of patients with the discharge diagnosis of AMI. LOCATION: A central hospital in the North of Portugal. SUBJECTS: One hundred and ninety-one patients admitted to the Internal Medicine Department of a central hospital in the North of Portugal between January 1, 1993, and December 31, 1994. RESULTS: Thrombolytic therapy was performed in 24.1% of the patients. At discharge 32.6% of the patients were on therapy with beta blockers, 68% with angiotensin converting enzyme inhibitors (ACEI) and 88.4% with aspirin. Stepwise logistic regression produced the following odds ratios for the variables significantly associated with: a) thrombolytic therapy: hypertension - 0.38; non-Q wave infarction - 0.17; time between onset of symptoms and hospital admission greater than 6 hours - 0.18; admission to coronary unit - 14.72; b) beta blocker therapy: age > 60 years - 0.23; serum LDH > 1000 U/L - 0.41; diastolic blood pressure > 85 mmHg - 3.73; Killip > 1 - 0.08; concomitant therapy with calcium antagonist - 0.33; previous therapy with beta blocker - 14.87; hospital stay greater than 10 days - 2.67; c) ACEI therapy: anterior wall infarction - 3.07; non Q wave infarction - 0.13; congestive heart failure - 9.36; serum creatinine > or = 15 mg/dl - 0.03. CONCLUSIONS: Beta blockers and thrombolytic are under used and ACEI overused. The delay in hospital admission is the most important factor opposing the use of thrombolytic therapy, imposing the need for measures that ean reduce this delay. Therapy with beta blockers (highly cost-effective) can be increased by educational intervention among the physicians. The overuse of ACEI can be ascribed to the good results of randomised trials.

Diltiazem effects on left ventricular function preliminary results of 12 patients evaluated by calibrated apexcardiogram.

Diltiazem is a calcium channel blocker whose effects on left ventricular function (LVF) are controversial. We studied 12 patients with ischemic heart disease (IHD) before starting and 15 and 30 days after having initiated Diltiazem 60 mg t.i.d. LVF was accessed by means of the normalized indexes of the calibrated apexcardiogram: nS for systolic LVF evaluation and nA for diastolic LVF evaluation. Recent works have shown that these indexes have a good correlation with invasive parameters of LVF. We verified that nS did not change and nA decreased significantly (p < 0.05) after Diltiazem. We preliminary concluded that Diltiazem has no deleterious effect on LV systolic function and improves LV diastolic function, by decreasing nA, a parameter which correlates well with LV end diastolic pressure.

Phonomechanocardiographic parameters in patients with atrial septal defect.

The purpose of the present study was to noninvasively evaluate left (LV) systolic and diastolic function in patients with atrial septal defect (ASD) using the phonomechanocardiogram. We studied 40 patients with atrial septal defect, 16 males and 24 females, ages ranging from 6 to 56 years (mean 21.1 years), consecutively observed before surgery in our institution, during a four year period. We measured the systolic time intervals (Q-A2c, Q-S1, ICT, PEP, LVETc, PEP/LVET), the Apex Cardiographic (ACG) diastolic parameters A2-Oc and A/H and the hemodynamic variables Qp/Qs, Pulmonary Vascular Resistance (PVR) and Left Ventricular End Diastolic Pressure (LVEDP). We compared the data with 74 normal individuals using the Student t-test and linear regression analysis. We found significant Q-S1 lengthening (81.2 +/- 16.4 ms, p < 0.001); PEP, ICT and A2-Oc were significantly reduced (101.2 +/- 21.7 ms, p < 0.001, 20.0 +/- 5.3 ms, p < 0.05 and 117.1 +/- 26.3 ms, p < 0.001, respectively) and A/H was significantly increased (17.4 +/- 12.1%, p < 0.005). Except for the case of Q-S1, where there was a weak positive linear correlation with Qp/Qs (r = 0.37), we found no correlation between the other parameters and Qp/Qs or PVR. Sixty-seven percent of the patients had Q-S1 prolongation and a Q-S1 > 76.2 ms identified left-right shunts > 2 with a positive predictive value of 82%; 62% of the patients had a reduced A2-Oc and a A2-Oc < 110 ms identified shunts > 2 with a positive predictive value of 90%.(ABSTRACT TRUNCATED AT 250 WORDS)

[Variability of heart rate: a perspective]. / Variabilidade da frequência cardíaca: uma perspectiva.

The present work is an attempt to provide a general overview on the current methods and applications of heart rate variability (HRV), starting from the underlying mechanisms of cardiac rhythmic automaticity and the influence on heart rate of biological modulators, namely autonomous nervous system. Different evaluation methods for HRV are compared in what concerns the duration of the records under analysis and the mathematical approach (spectral/non-spectral). Finally, clinical applications of HRV are mentioned, some of them the Department is particularly interested in, namely coronary heart disease, heart failure and diabetic neuropathy. The authors conclude, minding some aspects susceptible of discussion in the future of this technique.

[The SAVE trial: rational basis, results, and reflections]. / Estudo "SAVE": bases racionais, resultados e reflexões.

Recent concepts about post-infarction left ventricular remodeling, which is the basis for heart failure in these patients, as well as its prevention by ACE inhibitors are briefly summarized. Those data were the rationale for the SAVE trial. The most important initial aspects of this trial (general objective, pre-specified endpoints, inclusion and exclusion criteria, etc.) are then described as well as the basal characteristics of the respective cohort. The most important results of the SAVE trial, now in press, are subsequently presented. Several clinical guidelines, derived from these results, are then suggested. Finally, some new questions, both clinical and pathophysiological, and originated by the results from the SAVE results, are commented.