Biomedical subjects
Publications and source records attributed to R Ricci.
We report a case of bladder obstruction in a patient with Hunter's syndrome, presenting with acute painful symptomatology, due to the impossibility of voiding, which was diagnosed with ultrasonography and cystometrography. Intermittent catheterization with intravesical oxybutynin chloride lead to successful functional resolution of the obstruction.
Three groups of patients (right brain-damaged patients with or without left neglect, and left brain-damaged patients) and a group of healthy subjects, matched for age and educational level to the three groups of patients, were asked to report which of the two frontal surfaces of Necker cubes oriented in four different ways looked, at first sight, nearer to the viewer. The extent to which, and the way in which, disambiguation of the apparent perspective of Necker cubes occurred was found to vary across the four orientations and to be different in left-neglect patients compared with subjects of the other three groups. With normal subjects, the disambiguating factor is suggested to be a disposition to perceive the upper surface, which is nearly orthogonal to the frontal plane, as external to the cube. This would result from a navigation of the observer's spatial attention towards its target along a particular path that is altered in patients suffering from left neglect. It is suggested that comparison of the paths followed by the attentional vectors of normal subjects and left-neglect patients is potentially fruitful for a better understanding of the brain's normal mechanisms of spatial attention and of unresolved issues concerning the perception of the Necker cube.
Cockayne syndrome (CS) is a rare autosomal recessive disorder characterized by postnatal growth failure, mental retardation and otherwise clinically heterogeneous features which commonly include cutaneous photosensitivity. Cultured cells from sun-sensitive CS patients are hypersensitive to ultraviolet (UV) light and, following UV irradiation, are unable to restore RNA synthesis rates to normal levels. This has been attributed to a specific deficiency in CS cells in the ability to carry out preferential repair of damage in actively transcribed regions of DNA. We report here a cellular and molecular analysis of three Italian CS patients who were of particular interest because none of them was sun-sensitive, despite showing most of the features of the severe form of CS, including the characteristic cellular sensitivity to UV irradiation. They all were altered in the CSB gene. The genetically related patients CS1PV and CS3PV were homozygous for the C1436T transition resulting in the change Arg453opal. Patient CS2PV was a compound heterozygote for two new causative mutations, insertions of an A at position 1051 and of TGTC at 2053, leading to truncated proteins of 367 and 681 amino acids. These mutations result in severely truncated proteins, as do many of those that we previously identified in several sun-sensitive CS-B patients. These observations confirm that the CSB gene is not essential for viability and cell proliferation, an important issue to be considered in any speculation on the recently proposed additional function of the CSB protein in transcription. Our investigations provide data supporting the notion that other factors, besides the site of the mutation, influence the type and severity of the CS clinical features.
We investigated human thymic tissue by immunohistochemistry and in situ hybridization for the presence of synaptophysin-producing cells. Our results indicate that anti-synaptophysin antibody detected immunoreactive material in nerve fibers around vessels located in major thymic septa, in a relevant number of cortical epithelial cells, and in scattered epithelial cells in the medulla. The epithelial nature of synaptophysin-positive cells was documented by the co-expression of cytokeratins as revealed by double immunofluorescence. In situ hybridization studies revealed the presence of synaptophysin mRNA in cells mainly located in the cortex, the specific fluorescent signals being localized in the cell cytoplasm. Western blot analysis using an affinity-purified polyclonal antibody revealed an immunoreactive band of about 38 kD in the extracts from unfractionated thymic tissue and from epithelial cell-enriched fractions. No staining was observed in isolated thymocytes. The expression of synaptophysin in epithelial cells of the thymic cortex suggests that this protein may be involved in secretory activities related to T-cell maturation.
UNLABELLED: The RIMA (Rimodellamento Infarto Miocardico Acuto) study was designed to assess the relative effects of angiotensin-converting enzyme (ACE) inhibition by captopril, beta-blocker therapy by metoprolol, and their combination in patients with a first acute myocardial infarction on: 1. echocardiographically detected left ventricular remodeling; 2. prognosis. The second goal will be the argument of the present paper. Two-hundred fifty < or = 75 years consecutive patients (mean age: 58 yrs, males = 203) with acute myocardial infarction were randomly allocated to receive for > or = 3 months captopril (up to 75 mg/day, Group 1), metoprolol (up to 200 mg/day, Group 2) or captopril + metoprolol (Group 3) starting in the first 24 hours after the onset of symptoms. Intravenous beta-blockers in the acute phase of myocardial infarction and all other cardioactive drugs were allowed. The effect of the randomized therapy at six months from admission to the coronary care unit was considered in relation to: 1. recurrence of spontaneous cardiac events and of elective revascularization procedures; 2. adverse reactions (hypotension, atrioventricular block, cough, allergy, need of beta-blockers in Group 1, need for ACE inhibition in Group 2) requiring treatment modification based on physician's decision. RESULTS: Definite follow-up data were available in 226 patients and 195/226 patients (86%) had a complete treatment period. In these patients (per protocol analysis), 37 spontaneous cardiac events occurred: cardiac death = 6, non-fatal reinfarction = 9, unstable angina requiring hospitalization = 16, congestive heart failure = 6. Moreover, seven patients received a coronary revascularization procedure. Events occurred in 11/67 patients from Group 1, 16/63 patients from Group 2, 10/65 patients from Group 3 (16% vs 25% vs 15%, p = 0.28). The multiple logistic regression analysis demonstrated an increased odds ratio (OR) for spontaneous cardiac events in patients from Group 2 (OR = 2.82, 95% Cl: 1.16-6.87: p < 0.05). Elective revascularization procedures were statistically less frequent in patients treated with metoprolol (Group 1 = 9%, Group 2 = 1.6%, Group 3 = 0%; Group 1 vs Groups 2 and 3; p = 0.03). The intention-to-treat analysis on the overall population (226 patients) confirmed the presence of a trend towards a higher risk in patients from Group 2 (OR = 2.1, 95% Cl: 0.96-4.59; p = 0.06). Adverse reactions were observed in 16 patients from Group 1, 6 patients from Group 2 and 15 patients from Group 3 (22% vs 10% vs 23%; Group 2 vs Groups 1 and 3; p = 0.08). At the multivariate regression analysis, a trend towards less adverse reactions in patients assigned to the beta-blocker therapy alone was confirmed (OR = 0.41, 95% Cl: 0.15-1.13; p = 0.07). CONCLUSIONS: In a randomized early post-infarction treatment strategy, ACE inhibition with captopril alone or in combination with metoprolol demonstrated an increased protection against spontaneous cardiac events at six months in comparison with metoprolol alone. On the other hand, the beta-blocker treatment was associated with a lower number of elective revascularization procedures and appeared better tolerated than ACE inhibition.
Since the early nineties, the employment of DDD pacing from a right ventricular site with a short AV delay in patients with severe heart failure has led to considerable conflicting results, so that the real benefit of this method remains to be defined even in selected patients, such as those with first-degree AV block, QRS duration > 140 ms due to left bundle branch block (LBBB), mitral regurgitation time > or = 450 ms and diastolic filling time < or = 200 ms. Indeed, the asynchronous activation induced by pacing the right apex is the most important limitation to the technique, particularly in patients without an LBBB pattern or in those with an incomplete LBBB pattern. Recent studies have also shown that pacing of the right interventricular septum provides no better results than pacing of the right apex, at least in selected patients with no LBBB pattern and no significant mitral regurgitation. Today, it has been suggested that permanent biventricular pacing could be proposed as a feasible and reliable approach to improving ventricular function through the synchronization of the septum and the apex of the left ventricle, particularly in patients with a marked delay in ventricular activation sequence. This technique may be performed by means of transvenous leads inserted through the coronary sinus into the cardiac veins to stimulate both ventricles simultaneously, starting from the right apex and left lateral wall. Consequently, this approach supplies a strong basis for initiating further studies to examine the chronic effects of left ventricular pacing in patients with severe heart failure. We also suggest that the new tissue Doppler imaging techniques could usefully be applied to accurately select candidates to biventricular pacing.
A case of cardiac variant of Fabry's disease mimicking hypertrophic cardiomyopathy is reported. The diagnosis was obtained by biventricular endomyocardial biopsy showing severely hypertrophied myocardiocytes with large periodic acid-Schiff and Sudan black positive perinuclear vacuoles, shown at electromicroscopy to consist of lamellated cytoplasmic figures highly suggestive of Fabry's disease, and confirmed by diagnostic low activity of alpha-galactosidase A in the peripheral lymphocytes. Invasive approach was suggested by the occurrence of a long-standing atrial fibrillation that failed to determine deterioration of cardiac function. Differential diagnosis between hypertrophic cardiomyopathy and the cardiac variant of Fabry's disease is relevant for prognostic and therapeutic implications including the perspective of an enzyme replacement therapy.
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Prevalence and prognostic significance of painful and silent ischemia detected by exercise electrocardiography (ECG) and dobutamine stress echocardiography (DSE) were evaluated in 407 consecutive patients recovering from acute myocardial infarction. Painful ischemia assessed by both tests was not associated with different clinical characteristics of patients; on the other hand, it identified a higher risk subgroup compared with silent ischemia during exercise ECG but not during DSE.
Perceptual and response bias in estimating the proportion of the two segments of prebisected lines were disambiguated in a group of 121 patients suffering from left neglect by means of two variants of the Milner Landmark task (Milner et al., 1993). The first variant, LANDMARK-V, required a verbal response; the second variant, LANDMARK-M, required manual pointing. The paper reports and discusses the results obtained on each task and their correlations, as well as the relationships between either kind of bias and the intrahemispheric location of the lesion. It is argued that besides their usefulness as a diagnostic tool the proposed variants of the Milner Landmark task provide results that are worth further investigation in their own right.
UNLABELLED: Ninety-one right brain-damaged patients with left neglect and 43 right brain-damaged patients without neglect were asked to extend horizontal segments, either left- or rightward, starting from their right or left endpoints, respectively. Earlier experiments based on similar tasks had shown, in left neglect patients, a tendency to overextend segments toward the left side. This seemingly paradoxical phenomenon was held to undermine current explanations of unilateral neglect. The results of the present extensive research demonstrate that contralesional overextension is also evident in most right brain-damaged patients without contralesional neglect. Furthermore, they show that in a minority of left neglect patients, the opposite behavior, i.e., right overextension can be found. The paper also reports the results of correlational analyses comprising the parameters of line-extension, line-bisection, and cancellation tasks, as well as the parameters relative to the Milner Landmark Task, by which a distinction is drawn between perceptual and response biases in unilateral neglect. A working hypothesis is then advanced about the brain dysfunction underlying neglect and an attempt is made at finding an explanation of neglect and the links between the mechanisms of space representation and consciousness through the study of the changes induced by unilateral brain lesions in the characteristics of space-coding neurons. ABBREVIATIONS: C, control group; GN+91, full group of neglect patients; GN+27, group of neglect patients with relative left overextension; GN+14, group of neglect patients with relative right overextension; GN-43, full group of non-neglect patients; GN-9, group of non-neglect patients with relative left overextension; H canc, H cancellation task; LE, left extension; LE/RE, ratio of left-right extension; N+, neglect patients; N-, non-neglect patients; PB Land-M, perceptual bias on Landmark motor task; PB Land-V, perceptual bias on Landmark verbal task; RB Land-M, response bias on Landmark motor task; RB Land-V, response bias on Landmark verbal task; RE, right extension.
BACKGROUND: Thrombolysis has reduced early and longterm mortality by about 20%; sometimes, however, there is a re-occlusion of the infarct related artery or an unsuccessful thrombolysis. In these situations, there is a possible increase in detrimental events in the follow-up. OBJECTIVES: The aim of the study was to compare the prognostic value of dobutamine echocardiography (DET) and ECG exercise test (EET) in pts submitted to thrombolysis. METHODS: One hundred and fifty-one pts, with acute uncomplicated myocardial infarction, were enrolled. The pts were able to perform EET and had a sufficient echocardiographic window; 58 had anterior myocardial infarction (38%), 79 had inferior (52%), 2 had lateral (1%), 12 had non-Q (8%). EET was performed with an initial load of 25 Watt, and thereafter, 25 W every two minutes. DET was performed with step-wise infusion every three minutes (5, 10, 20, 30 and 40 mcg/kg/min.). If the target heart rate was not reached, a further dose of 40 mcg/kg/min. together with atropine 0.25-1 mg was administered, in the absence of signs and symptoms of ischemia. RESULTS: During a mean (+/- SD) follow-up period of 8 +/- 4.5 months (range 1-23), 16 spontaneous events happened (4 deaths, 5 non-fatal re-infarctions, 7 unstable angina). One-hundred and three EET (68%) were negative for ongoing ischaemia, while 48 were positive, 79 DET (52%) were negative for ongoing ischaemia and 72 were positive (48%). Statistical results: DET and EET had a sensitivity of 41% and 54%, a specificity of 57% and 74%, a positive predictive value of 7% and 14%, a negative predictive value of 91% and 95%, an accuracy of 56% and 73%. Kaplan-Maier survival curves demonstrated that patients with Peak Wall motion > 1.8 and EET score > 3, had the higher risk of spontaneous events. CONCLUSION: A few spontaneous events happened in the follow-up. These data demonstrate that patients treated with thrombolysis are not at high risk of spontaneous events. DET and EET, therefore, have had a high negative predictive value. For this reason, we can conclude that pts with negative tests can be considered at low risk and do not need any further investigations.
Eighteen patients affected by glial brain tumors were examined by localized single voxel magnetic resonance spectroscopy (1H MRS). For all patients histological diagnosis was obtained after stereotactic biopsy or surgical removal of the tumor. Histological nuclear atypia, tumor cellularity, necrosis, vascular proliferation and percentage of Ki-67 positive cells in the total cell populations were evaluated. It was found that some of the in vivo 1H MRS parameters were related to the histological features of the tumor. In particular, the Choi/Cri metabolite ratio obtained from the neoplastic tissues paralleled the Ki-67 cell proliferation index. For some of the patients 1H and 13C in vitro high resolution magnetic spectroscopy of surgical specimens was also carried out. 1H MRS of aqueous extracts from different biopsy specimens of the same tumor furnished fine biochemical information on intratumor heterogeneity. The degree of histological vascular proliferation of the tumor was correlated to the presence of cholesteryl esters in the 13C spectrum of the lipid fraction of surgical specimens.
UNLABELLED: Recent reports suggest a relationship between ECG changes and myocardial viability during dobutamine stress echocardiography in patients with myocardial infarction. The aim of the study was to analyze the predictive value of T-wave normalization and ST segment elevation during low- (10 mucg/Kg/m') and high-dose (40 mucg/Kg/m') dobutamine stress test for late spontaneous recovery of function in patients with a first uncomplicated Q-wave myocardial infarction. METHODS: Seventy eight consecutive patients (59 +/- 9 yrs; males = 67; anterior MI = 41, inferoposterior MI = 37 pts) underwent baseline 2D echo and dobutamine stress test at 9 +/- 2 days from onset of symptoms and they were free of cardiac events during the first three months after myocardial infarction. T-wave normalization (negative T-wave becoming > or = 1 mm upright in > or = 2 leads) and ST segment elevation (> or = 0.1 mm in > or = 2 leads) at low- and high-dose dobutamine infusion were compared with an improvement of contractility in the infarct area detected echocardiographically at three months. A wall motion score decrease in infarct area > or = 2 was the criterion for recovery of contractility. RESULTS: ST segment elevation occurred in 19/78 patients at low dose (24%) and in 45/78 patients at high dose (58%). Late recovery of contractility in the infarct area was observed in 38/78 patients (49%). The positive and negative predictive values of ST segment elevation for late recovery of contractility were, respectively, 63-56% at low dose and 47-48% at high dose. A baseline negative T-wave in > or = 2 leads was present in 56 patients, and 27 (48%) showed recovery of contractility at three months. T-wave normalization occurred in 14 patients at low-dose (25%) and in 29 patients at high-dose dobutamine infusion (52%). The positive and negative predictive values of T-wave normalization were, respectively, 71-59% at low dose and 62-67% at high dose. Both ECG markers were present in 10/56 patients at low dose and in 19 patients at high dose. The positive and negative predictive values, respectively, were 70-57% at low dose and 58-57% at high dose. At univariate analysis, neither the ECG changes alone nor their combination during dobutamine stress testing were shown to be significant predictors of recovery of function. CONCLUSIONS: Our study demonstrates that in patients with a first uncomplicated Q-wave myocardial infarction, the T-wave normalization and/or the ST segment elevation occurring during early dobutamine stress testing are not reliable predictors of late spontaneous recovery of contractility in the infarct area.
We analyzed the relation between dobutamine-induced Q-wave ST-segment elevation and regional contraction during low (5 to 10 microg/kg/min) and high doses (20 to 40 microg/kg/min) of dobutamine in a series of 391 dobutamine echocardiographic tests performed 10 +/- 2 days after a first uncomplicated acute myocardial infarction (AMI). ST-segment elevation was defined as > or = 1 mm new or additional J-point elevation with a horizontal or upsloping ST segment lasting 80 ms. Wall motion score index at rest was derived using a 16 segment-4 grade score model. Patients with dobutamine-induced ST-segment elevation had a higher wall motion score index at rest (anterior wall AMI: 1.67 +/- 0.27 vs 1.43 +/- 0.30, p = 0.0001; inferior wall AMI: 1.44 +/- 0.27 vs 1.30 +/- 0.18, p = 0.0001) and similar incidence and extent of myocardial viability and homozonal ischemia in comparison with those without ST-segment elevation. The sensitivity, specificity, and accuracy of dobutamine-induced ST-segment elevation for detecting residual homozonal ischemia were 51%, 55%, and 54%, respectively, in patients with anterior wall AMI, and 42%, 68%, and 58%, respectively, in patients with inferior wall AMI. In conclusion, dobutamine-induced ST-segment elevation is not associated with higher incidence and extent of viable or jeopardized myocardium but rather to a greater extent of wall motion abnormalities at rest. Thus, this finding does not represent a clinically reliable discriminator for selecting patients for coronary angiography and possible revascularization procedures.
We examined 14 vegetative brain-injured patients with proton magnetic resonance single-volume spectroscopy (1H MRS) at 1.5 T to establish whether there were changes in relative concentrations of N-acetyl aspartate (NAA), choline (Cho) and creatine (CR) metabolites from those found in healthy brains. Spectra were obtained from two different (2 x 2 x 2 cm) volumes of interest in the left and in the right frontal cortex, normal on MRI. All spectra revealed abnormalities compared with normal spectra obtained from age-matched control subjects. Values outside the normal range for at least one of the metabolite ratios were observed in all patients. Cho/Cr was markedly higher and NAA/Cho and NAA/Cr were markedly lower than in the control subjects. At different times six patients regained awareness and the ability to obey commands, and four were re-examined; changes in metabolite ratios were observed, which were different in individual patients. The NAA/Cho ratio reaches statistical significance in discriminating between the patients with a poor outcome (death or prolonged vegetative state) and those who regained awareness; the dividing line appears to be at a value of about 1.6.
Space constancy was investigated in seven blindfolded left-neglect patients by driving them along routes involving one or two, left or right, 90 degrees turns. At the end of each route patients had to indicate its starting point while still blindfolded. On average, no considerable left/right differences were found in pointing accuracy. The entailments of this finding for the understanding of neglect phenomena are briefly discussed.
AIMS: An abnormal left ventricular volume response during dobutamine echocardiography identified patients with severe coronary artery disease. The aim of the study was to assess the prognostic value of left ventricular volume changes during dobutamine stress echocardiography in 136 patients. METHODS AND RESULTS: Endpoints were defined as spontaneous cardiac events at follow-up. Left ventricular end-diastolic and end-systolic volume changes (abnormal response: < 10% and < 20% decrease, respectively) were compared with other clinical and stress test variables. During 18 +/- 7 months of follow-up, 31 cardiac events occurred: 12 hard events (cardiac death [n = 6], myocardial infarction [n = 6]) and 19 soft events (unstable angina [n = 16], congestive heart failure [n = 3]). End-diastolic volume response (P = 0.006), diabetes (P = 0.008), inducible wall motion abnormalities (P = 0.024), end-systolic volume response (P = 0.039) and inducible angina (P = 0.038) were related to a greater likelihood of cardiac events. The Cox regression analysis revealed end-diastolic volume response (odds ratio: 3.0; CI 1.44-6.32) and diabetes (odds ratio: 2.7; CI 1.28-5.69) to be independent predictors of spontaneous cardiac events. Diabetes (odds ratio: 4.0; CI 1.26-12.80) and < 40% baseline ejection fraction (odds ratio: 2.21; CI1.14-4.29) were independent predictors of hard events. CONCLUSION: An abnormal end-diastolic volume response during dobutamine stress echocardiography identifies patients with an unfavourable outcome; they should be considered for more accurate prognostic stratification.