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Parkinson's disease (PD) has been described as a disconnection syndrome. The lateralized motor onset of symptoms indicates asymmetrical dysregulation of the dopamine production in the substantia nigra, in the striatum and, in turns, a dysfunction of the basal ganglia and of the connected cortical areas. However, lateralization of cognitive symptoms is less clear, and it would be important to determine whether lateralized motor deficits are associated with cognitive impairments typically documented following damage to one specific hemisphere. We tested twenty-two PD patients at various stages of the disease on a sustained attention task, namely a multiple object tracking (MOT). This task is particularly sensitive at revealing lateralized deficits, and is often used to diagnose visual field attentional deficits in stroke patients with unilateral parietal lesions. In the present study, PD patients were asked to track four moving discs (two in the left and two in the right hemifield) amidst moving distracters. Left and right visual field tracking accuracy was psychophysically measured and compared to that of age-matched controls. Results revealed distinct behaviors: left (motor deficit) PD patients showed impaired performance in the left, while right (motor deficit) PD patients were impaired in the right hemifield. Data indicate that PD affects motor as well as attentional functions. Interestingly, performance correlated with scores on the Montreal Cognitive Assessment (MoCA) a measure of cognitive functioning. Crucially, results suggest that cognitive skills might be affected as early as motor functions, and that early evaluation might be key to predicting disease progression and planning interventions.

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Polychlorinated biphenyls (PCBs) exist as 209 congeners, consisting of biphenyl molecules, where the number and substitution positions of halogen atoms are known to affect industrial uses, environmental transport mechanisms, distribution, fate, and toxicity. The complexity of the problem requires accurate physicochemical studies of an increasing number of congeners in order to understand the environmental and biological processes at play. This work presents a systematic study on the thermodynamic and kinetic properties of PCBs by quadrupole ion trap mass spectrometry. A clear relationship between structure and behavior of PCBs in mass spectrometry experiments has been observed. Overall data demonstrate that di-ortho congeners show lower thermodynamic stability and higher fragmentation rate than non/mono-ortho. Congeners follow different fragmentation mechanisms according to the number of chlorine atoms in ortho position of the biphenyl system. Experimental kinetic curves of mono/non-ortho and di-ortho congeners show a strong similarity with classical first-order kinetics curves; in particular, di-ortho congeners follow a first-order consecutive reaction, while mono/non-ortho follow a first-order parallel reaction. For each studied congener, the kinetic constant of reaction (fragmentation) has been determined. Data support environmental levels and biochemical transformations described in literature. The general picture of the PCB behavior inside a quadrupole ion trap provides the basis for the development of reliable and cost-effective analytical methods to the determination of ultra-low level trace of PCB congeners.

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Worldwide polychlorinated biphenyls (PCBs) pollution is due to complex mixtures with high number of congeners, making the determination of total PCBs in the environment an open challenge. Because the bulk of PCBs production was made of Aroclor mixtures, this analysis is usually faced by the empirical mixture identification via visual inspection of the chromatogram. However, the identification reliability is questionable, as patterns in real samples are strongly affected by the frequent occurrence of more than one mixture. Our approach is based on the determination of a limited number of congeners chosen to enable objective criteria for Aroclor identification, summing up the advantages of congener-specific analysis with the ones of total PCBs determination. A quantitative relationship is established between congeners and any single mixture, or mixtures combination, leading to the identification of the actual contamination composition. The approach, due to its generality, allows the use of different sets of congeners and any technical mixture, including the non-Aroclor ones. The results confirm that PCB environmental pollution in northern Italy is based on Aroclor. Our methodology represents an important tool to understand the source and fate of the PCBs contamination.

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Although researchers are now familiar with progressive supranuclear palsy (PSP) and its characteristic "subcortical" dementia, this was not the case prior to seminal descriptions by Steele, Richardson, Olszewski and Albert. In fact, the first three authors identified this disorder, and the last one introduced the classification of the dementias according to the anatomical involvement. This paper is in honor of their contributions, and will also outline the changes that have occurred since their seminal works.

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BACKGROUND: After a modified Fontan procedure with atriopulmonary or atrioventricular conduit, some patients present stress intolerance, supraventricular arrhythmia, recurrent pleuropericardial or ascitic effusions, and protein-losing enteropathy, all of which are signs that the previous procedure has failed. The aim of this study was to evaluate the midterm outcome after surgical therapy for this condition. MATERIAL AND METHODS: Between August 1994 and December 1997, nine patients (6 males and 3 females), age 10 to 39 (mean 21.5) years, underwent conversion of previous modified Fontan procedure to total extracardiac cavo-pulmonary connection. Time from the previous procedure was 6 to 18 years (mean 10). Diagnosis was tricuspid atresia with pulmonary stenosis (n = 2), double-inlet left ventricle and concordant ventriculoarterial connection (n = 3), double-inlet left ventricle and discordant ventriculoarterial connection (n = 3), Holmes heart (n = 1). Nine patients presented decreased stress tolerance, seven had arrhythmia, five had pleuropericardial effusions and two had protein-losing enteropathy. In all but one patient, right atrial pressure was higher than 15 mmHg, while in six patients the cardiac index was less than 2 l/min/m2. A polytetrafluoroethylene non-valved conduit was interposed between the inferior vena cava and the right pulmonary artery for conversion in all patients. A bidirectional cavo-pulmonary anastomosis (modified Glenn) was associated in all patients. Evaluation was done by NYHA Class and by an arbitrary score assigned to patients based on 7 parameters. RESULTS: There was no perioperative mortality. All patients were clinically improved at a mean follow-up of 24 months (range: 3 to 46). No patient had effusions, and the arrhythmias disappeared in 4 patients and were controlled by medical therapy in one. The two patients with protein-losing enteropathy improved markedly within 30 days and the score dropped below 10 points. CONCLUSIONS: The conversion of the modified Fontan procedure to total extracardiac cavo-pulmonary connection improves clinical condition by decreasing the right atrium-pulmonary gradient and right atrial preload, and by providing a laminar cavo-pulmonary flow without any need for intracardiac anastomoses. This procedure should be undertaken early in this subset of patients, before ventricular failure ensues.

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This study using pulsed and continuous wave Doppler echocardiography was designed to achieve a cross-sectional echocardiographic categorization of the fibrous tissues in the environs of perimembranous ventricular septal defects, to determine the mechanism involved in its formation and for qualitative and quantitative evaluation of the anomalies associated with the entity. A total of 67 patients was studied, 23 presented cross-sectional echocardiographic evidence of perimembranous ventricular septal defect in isolation, 12 associated with tissue 'tags' and 32 combined with 'restrictive' tissue in the area of the defect. Four echocardiographic features of the 'restrictive' tissue were observed. In 23 of these 32 patients, it was possible to identify the exact anatomic origin of the 'restrictive' tissue (in seven complete and, in 15, partial involvement of the septal leaflet of the tricuspid valve; in one, prolapse of the aortic valve with a partial involvement of the tricuspid septal leaflet) while in nine the origin remained undetermined. In 20, the 'restrictive' tissue simultaneously protruded into the right atrium and ventricle; only in 12 did it extend exclusively into the right ventricle. Tricuspid insufficiency was detected by pulsed Doppler in 78% of the patients with 'restrictive' tissue and in 23% of the remaining patients. Tricuspid incompetence was severe in only two patients of the first group. Three patients with 'restrictive' tissue (9%) had obstruction to the outlet of the right ventricle and four (13%) patients presented aortic insufficiency. Five patients (16%) with 'restrictive' tissue closing the defect did not present pulsed Doppler evidence of a shunt at the ventricular level.(ABSTRACT TRUNCATED AT 250 WORDS)

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This report describes a 7 year old boy with a history of recurrent respiratory infections, a 3/6 ejection systolic murmur and a right supraclavicular systolic thrill. Chest x-ray showed widening of the superior mediastinum towards the right, and barium esophagram demonstrated anterior displacement and compression of the esophagus. Cross-sectional echocardiography revealed a transverse aortic arch segment. Thus, the findings described above suggested the noninvasive diagnosis of the right cervical aortic arch. A peripheral intravenous digital subtraction angiography was necessary to evaluate the origin of the epi-aortic arteries and it proved adequate for the follow-up of these patients.

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An intracardiac tumour in an asymptomatic female infant was diagnosed by means of echocardiography and magnetic resonance. The natural history of this pathology in patients showing no symptoms of cardiac involvement is still unknown. The development of these modern diagnostic techniques, however, has made it easier to carry out longitudinal follow-up studies aimed at obtaining useful information about the prognosis and growth potentialities of these tumours.

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We designed this study in order to evaluate those cross-sectional echocardiographic projections of most value in the diagnosis of ventricular septal defects and to compare the techniques of cross-sectional and Doppler echocardiography in these lesions. We studied 71 cases with ventricular septal defects confirmed by cross-sectional and/or pulsed Doppler echocardiography. The defect was imaged by cross-sectional echocardiography in 49 patients but not imaged in 22. In the group of 49 patients, except two with pulmonary hypertension, pulsed Doppler enabled us to detect a left-to-right shunt at ventricular level. In the second group of 22 patients, a positive pulsed Doppler signal was detected in the ventricles although no defect was visualized. Pulsed Doppler examination supplemented the information detectable from cross-sectional echocardiography in small defects; in the diagnosis of multiple septal defects; in the presence of aortic valve regurgitation in doubly committed and subarterial defects; in those having residual shunts after surgical correction; and in those with tricuspid valve regurgitation in the setting of perimembranous defects. Continuous wave Doppler cannot always be reliably employed in the evaluation of transventricular pressure gradient because of a failure to align with the jet in the presence of poor signals. The sub-costal oblique projections and the introduction of the right oblique sub-costal view proved, in our hands, to be the most important tools for identifying and classifying the various types of ventricular septal defect.

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The echocardiographic crux cordis is defined in normal subjects as the spatial interrelation between the atrial and ventricular septal planes and the plane of the atrioventricular (AV) junction. This crossroad can be visualized using apical, sub-costal, or precordial four-chamber echocardiographic projections. We studied this relationship in 33 patients with right AV valve atresia (29 with absent AV connection, 4 with an imperforate AV valve) and 14 with left AV valve atresia (9 with absent AV connection, 5 with an imperforate valve). An accurate diagnosis of AV valve atresia was successfully achieved in all patients, while the differentiation between an imperforate AV valve and absence of an AV connection was achieved in 45 out of 47 cases. Echocardiography demonstrated in some cases of absent AV connection, an arrangement which at first sight was analogous to that found in hearts with AV concordance and an imperforate AV valve. The differential diagnosis, therefore, must be based on the differing echocardiographic characteristics of the atretic atrial floor. In 31 out of 38 cases with absent AV connection it was possible to obtain simultaneous visualization of the ventricular septum and the atretic atrial floor. This proved helpful in planning the clinical management of these patients. The evaluation of crux cordis anatomy also differentiated AV valve atresia from other cardiac malformations with a similar presentation (valvular hypoplasia and common AV valve). It may prove the most reliable tool for the differential diagnosis of the spectrum of AV valve atresia.

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In the normal subject, the echocardiographic crux-cordis is defined by the spatial relationship between the plane of the interatrial and interventricular septa and the plane of the A-V valves. The bidimensional echocardiographic image of the crux-cordis may be obtained from various approaches: apical, subcostal, or precordial. In the present study we have assessed the usefulness of 2-D echocardiographic analysis of the crux-cordis in identifying the presence of a common A-V valve vs a single A-V valve (i.e. with atresia of the contralateral valve) in univentricular hearts (UH). We have studied 55 patients. Eight patients had a UH with a common A-V valve (6 with a rudimentary chamber, and 2 without a rudimentary chamber). Thirty-three patients were found to have atresia of the right A-V valve (29 with absent connection, and 4 with an imperforated valve), and 14 with atresia of the left A-V valve (9 with absent connection, and 5 with an imperforate valve). A correct differential diagnosis between common A-V valve and atresia of an A-V valve was achieved in 53 out of 55 patients through the direct visualization of the atretic atrial floor and by recognizing the origin of the leaflets of the one patent valve present. Of the patients with UH and common A-V valve, 5 presented a low interatrial septal defect, 3 a single atrium, 3 an interventricular septum which was clearly misaligned with the echocardiographic crux-cordis, in 5 an analysis of the crux-cordis did not permit visualization of a ventricular septal structure of which 3 resulted as false negatives.(ABSTRACT TRUNCATED AT 250 WORDS)

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