A surface acoustic wave bio-electronic nose for detection of volatile odorant molecules.

In this work, a "bio-electronic nose" for vapour phase detection of odorant molecules based on surface acoustic wave (SAW) resonators is presented. The biosensor system is composed of an array of five SAW resonators coated with three types of odorant-binding proteins (OBPs): the wild-type OBP from bovine (wtbOBP), a double-mutant of the OBP from bovine (dmbOBP), and the wild-type OBP from pig (wtpOBP). High resolution deposition of OBPs onto the active area of SAW resonators was implemented through laser-induced forward transfer (LIFT). The resonant frequency shifts of the SAW resonators after the deposition of the biomolecules confirmed the immobilisation of the proteins onto the Al/Au inter-digital transducers (IDTs). In addition, a low increase of insertion losses with a limited degradation of Q-factors is reported. The "bio-electronic nose" fabricated by LIFT is tested in nitrogen upon exposure to separated concentrations of R-(-)-1-octen-3-ol (octenol) and R-(-)-carvone (carvone) vapours. The "bio-electronic nose" showed low detection limits for the tested compounds (i.e. 0.48 ppm for the detection of octenol, and 0.74 ppm for the detection of carvone). In addition, the bio-sensing system was able to discriminate the octenol molecules from the carvone molecules, making it pertinent for the assessment of food contamination by moulds, or for the evaluation of indoor air quality in buildings.

Detection of odorant molecules via surface acoustic wave biosensor array based on odorant-binding proteins.

In this paper, we present an array of biosensors for vapour phase detection of odorant molecules based on surface acoustic wave (SAW) resonators coated with odorant-binding proteins (OBPs). For the first time, the sensing capabilities of three different OBPs, as sensitive layers for SAW devices, are studied and compared. The SAW biosensor array is composed of three SAW devices coated by the droplet method with the wild-type OBP from cow (wtbOBP), a double mutant of the OBP from cow (dmbOBP) and the wild-type OBP from pig (wtpOBP). An uncoated device is used to compensate the variations of the environmental parameters. The SAW devices consist of two-port resonators fabricated on quartz (ST-cut, x propagation) with electrodes made of aluminium covered with a thin gold film (2 nm thick). The obtained surface densities of OBP layers are between 1.18×10(-6) kg/m(2) and 2.31×10(-6) kg/m(2) and were calculated measuring the resonant frequency shift of the SAW devices after the coating. The SAW biosensor array was tested in nitrogen upon exposure to vapours of R-(-)-1-octen-3-ol (octenol), in the range of concentration between 13 and 61 ppm, and R-(-)-carvone (carvone), in the range between 9 and 80 ppm. The highest sensitivity for detection of octenol (25.9 Hz/ppm) was obtained using the wtpOBP-based SAW biosensor, while the highest sensitivity for detection of carvone (9.2 Hz/ppm) was obtained using the dmbOBP-based SAW biosensor.

X-ray beam monitor made by thin-film CVD single-crystal diamond.

A novel beam position monitor, operated at zero bias voltage, based on high-quality chemical-vapor-deposition single-crystal Schottky diamond for use under intense synchrotron X-ray beams was fabricated and tested. The total thickness of the diamond thin-film beam monitor is about 60 µm. The diamond beam monitor was inserted in the B16 beamline of the Diamond Light Source synchrotron in Harwell (UK). The device was characterized under monochromatic high-flux X-ray beams from 6 to 20 keV and a micro-focused 10 keV beam with a spot size of approximately 2 µm × 3 µm square. Time response, linearity and position sensitivity were investigated. Device response uniformity was measured by a raster scan of the diamond surface with the micro-focused beam. Transmissivity and spectral responsivity versus beam energy were also measured, showing excellent performance of the new thin-film single-crystal diamond beam monitor.

An extraordinary testimonial of thermal rehabilitation: Giuseppe Garibaldi - 2011: 150th Anniversary of the Italian Unification.

On the occasion of the 150th Anniversary of the Italian Unification, the discovery of some letters by Giuseppe Garibaldi - referring to a period of thermal treatments at the Baths in Civitavecchia (Rome) - gave us the opportunity for writing a commentary about a not well known experience in the Two World Hero's life: the numerous treatments carried out at many Italian spa centres for treating a rheumatic pathology (probably a rheumatoid polyarthritis) and the outcomes of various war wounds, especially the famous gunshot-wound in his right ankle during the Battle of Aspromonte, in 1862.

Decreased sympathetic inhibition in gastroesophageal reflux disease.

This study was undertaken to evaluate autonomic nervous system function in patients with gastroesophageal reflux disease. Based on clinical criteria, 28 consecutive patients with no history of heart, metabolic, or neurologic disease (mean age 41 y, range 20-62 y) reporting with upper gastrointestinal symptoms typical of gastroesophageal reflux underwent esophageal manometry, ambulatory 24-hour pH study with electrocardiographic monitoring, power spectral analysis of heart rate variability, and cardiovascular tests. Twelve healthy subjects served as controls. A positive result of prolonged esophageal pH study (pH in the distal esophagus less than 4, lasting more than 4.2% of recording time) was observed in 21 patients (reflux group); seven patients were categorized in the nonreflux group. No patient showed arrhythmias or any correlation between heart rate variability changes during electrocardiographic monitoring and episodes of reflux (pH less than 4, lasting more than 5 minutes). A decrease of sympathetic function occurred only in the reflux group (p <0.05) supported by the lower increase of systolic/diastolic blood pressure at sustained handgrip. No other cardiovascular tests showed statistically significant differences in the control or nonreflux groups. Total time reflux showed an inverse correlation with sympathetic function in the reflux group (r = -0.415, p <0.028). We concluded that there is some evidence for a slightly decreased sympathetic function in patients with gastroesophageal reflux disease that is inversely correlated with total time reflux. In these patients, decreased sympathetic function may cause dysfunction of intrinsic inhibitory control with increased transient spontaneous lower-esophageal sphincter relaxations, thus resulting in gastroesophageal reflux disease.

Effect of amlodipine on exercise-induced platelet activation in patients affected by chronic stable angina.

BACKGROUND: Literature concerning exercise-induced platelet activation in chronic stable angina is somewhat confusing. The reason lies in the type of exercise as well as in methodological problems. A powerful, recently introduced procedure to detect platelet activation is flow cytometry. Platelet response to activating factors is mediated by calcium uptake; however, calcium antagonist effect on platelet activity is still unclear. HYPOTHESIS: The study was undertaken to investigate exercise-induced platelet activation before and after treatment with amlodipine in chronic stable angina. METHODS: Twenty patients with chronic stable angina were entered into the study. Each subject underwent a symptom-limited cycloergometer stress test following a washout period of 2 weeks. Blood samples were collected before and immediately after exercise. All subjects were then randomized into two groups of 10 patients each, with Group 1 and Group 2 taking amlodipine 10 mg/day, and placebo for 4 weeks, respectively. They subsequently underwent a second exercise stress test, and blood samples were obtained before and immediately after exercise. Flow-cytometric evaluation of platelet activity was performed in order to recognize GMP-140 expression on platelet membrane. RESULTS: Strenuous exercise induced a significant increase in platelet activation in all subjects prior to therapy. No significant differences were observed in platelet activity at rest between Groups 1 and 2, whereas a significant decrease in exercise-induced platelet activation was demonstrated in Group 1 compared with Group 2. CONCLUSION: Our data provide evidence of the favorable effect of amlodipine on exercise-induced platelet activation in patients affected by chronic stable angina.

[The effects of a left bundle-branch block on ventricular repolarization dispersion]. / Effetti del blocco di branca sinistra sulla dispersione della ripolarizzazione ventricolare.

Patients with left bundle-branch block (LBBB) often present electrocardiographic abnormalities and, therefore, are excluded from studies concerning electrocardiographic evaluation of ventricular repolarization. The aim of the study was to assess whether LBBB could influence dispersion of ventricular repolarization. Surface electrocardiograms of 16 patients (9 males and 7 females, mean age 58 +/- 14 years) with episodes of intermittent LBBB were analyzed. Six patients were affected by coronary artery disease, 6 by hypertensive cardiomyopathy and 4 by dilated cardiomyopathy. Maximal QT and JT corrected intervals, QT and JT dispersion, and QT and JT dispersion corrected for heart rate, were obtained before and after LBBB. We observed a significant prolongation of maximal QT (412 +/- 29 vs 433 +/- 25 ms; p < 0.05), and of maximal corrected QT (457 +/- 37 vs 497 +/- 56 ms; p < 0.05) after LBBB. Maximal JT interval, also corrected for heart rate, did not show any significant modification after LBBB. Moreover, we did not observe any significant difference in electrocardiographic parameters of dispersion of repolarization. Our results seem to indicate that LBBB did not alter significantly dispersion of ventricular repolarization. QT dispersion is considered an important marker of risk for incidence of ventricular arrhythmias. If our results will be confirmed in larger groups of patients, analysis of QT dispersion could be extended even to patients with LBBB.

Malignant cardiac involvement in a family with myotonic dystrophy.

BACKGROUND: In patients with myotonic dystrophy, histopathological and electrophysiologic abnormalities of cardiac conduction system may lead to sudden cardiac death due to atrioventricular block or to ventricular electrical instability. METHODS: Four members of a family affected by myotonic dystrophy are reported, which underwent a cardiological examination including invasive electrophysiological study and prolonged follow-up. Other 3 members of the same family had died suddenly. No clinical data are available for 2 of these patients, while paroxysmal atrial flutter and non sustained ventricular tachycardia had been detected at Holter in the third one. RESULTS: Signs of atrioventricular conduction impairment, poorly predictable with non invasive electrocardiography, were found in the 4 patients undergoing intracardiac electrophysiologic study. In 2/4 patients, both having dizzy spells and the most impaired atrioventricular conduction, a pace-maker was implanted. Polymorphic, non sustained ventricular response was induced in 2/4 patients, 1 of them with spontaneous high grade ventricular arrhythmias. CONCLUSIONS: The respective role of atrioventricular conduction impairment and ventricular vulnerability in determining sudden death has not been stated so far in these patients. The observed polymorphic non sustained response should not be "a priori" disregarded as aspecific, since it could be the electrophysiological counterpart of a peculiar anatomic arrhythmogenic substrate. A comprehensive study, including invasive electrophysiology, is advisable in all patients with myotonic dystrophy whenever a member of their family presents with cardiac involvement, to assess the most probable life-threatening arrhythmogenic mechanism.

QT interval and QT dispersion in multiple system atrophy (Shy-Drager syndrome).

To evaluate the influence of autonomic function on the QT interval and QT dispersion, 18 patients (10 males and 8 females; mean age 61 +/- 9 years) with multiple system atrophy (MSA, Shy-Drager syndrome) were studied. Cardiovascular tests were performed to assess the degree of autonomic dysfunction. The QT interval, corrected QT (QTc), QT dispersion (QTd), corrected and adjusted QTd were calculated from a standard 12-lead electrocardiogram. Fifteen healthy subjects matched for sex and age were studied as controls. Nine MSA patients showed severe autonomic dysfunction with orthostatic hypotension. In the remaining patients definite autonomic impairment was found. No statistically significant difference was found in QTd and only a trend towards higher values of maximal QTc was found in patients compared with controls. QTc prolongation, defined as greater than the mean +/- 2 SD of the controls, was detected only in three out of the 18 MSA patients (17%). No correlation was found between the severity of autonomic impairment and repolarization parameters. Our data suggest that chronic autonomic impairment in patients with MSA does not significantly affect ventricular repolarization and ventricular dispersion.

Intravesical idarubicin: a dose-finding study.

A total of 12 patients with completely resected, recurrent papillary tumors of the bladder were entered into a dose-finding study using intravesical idarubicin, a new anthracycline agent that has been shown in vitro to be more active than doxorubicin or daunorubicin, its parental compound. Patients were scheduled to receive eight weekly instillations with the following dose levels: 6.5, 12.5, and 20 mg, all of them diluted in 50 ml saline. Each dose level was initially studied in 3 patients. Dose escalation in the individual patients was not allowed so as to avoid undue toxicity and to evaluate the cumulative toxicity induced by each dose level. Overall, 4 patients were withdrawn due to severe local toxicity (chemocystitis) after a median of 2 instillations (range 1-3) and 3 more patients refused to continue treatment due to mild to moderate toxicity after a median of 4 instillations (range 2-4). Both the patients treated with 20 mg idarubicin and 2 of the 6 patients treated with 12.5 mg were withdrawn due to local toxicity. In contrast, no systemic toxicity was encountered at any dose level. We conclude that doses ranging from 6.5 to 12.5 mg and concentrations varying between 0.125 and 0.250 mg/ml are more appropriate for phase II studies, implying repeated instillations. At these doses and concentrations, however, it is unlikely that idarubicin might be more active than doxorubicin or epirubicin, whereas it might be more toxic.

Combination therapy with subcutaneous interleukin-2 and interferon-alpha in advanced renal cancer patients with poor prognostic factors.

Sixteen patients with metastatic renal cell carcinoma were treated with a combination of low-dose subcutaneous interleukin-2 (IL-2) and recombinant interferon (IFN)-alpha. One treatment course included 6 weeks of treatment followed by a 2-week rest. Patients received therapy as outpatients. All patients were assessable for toxicity and response assessment. Nine patients experienced severe toxicities resulting in dosage modification. The major treatment-limiting side effects were gastrointestinal, cutaneous, fever and flu-like symptoms. One patient (6%) had partial remission and six patients (37.5%) had disease stabilization. Overall median survival was 8 months. In our study IL-2 and IFN-alpha showed a low activity and a quite high toxicity. It seems that the prognostic factors per se rather than treatment options might impact the treatment results in advanced renal cancer patients.

[Doppler evaluation of diastolic function in hypertrophic cardiomyopathy]. / La valutazione Doppler della funzione diastolica nella cardiomiopatia ipertrofica.

Diastolic function may play a significant role in patients affected by hypertrophic cardiomyopathy, because abnormalities in diastolic function, even in presence of a normal systolic function, may determine the clinical features of the disease. Doppler ecocardiography, using a non-invasive and not highly expensive method, easily allows to analize the indexes of diastolic function, as soon as some morpho-functional parameters, represented by extent and localization of the myocardial hypertrophy and presence or absence of obstruction in the left ventricular outflow, which have always been considered relevant in the prognosis together with the typical arrhythmic abnormalities of the disease. The aim of this study was to investigate the behaviour of Doppler ecocardiographic parameters of diastolic function in 38 patients with hypertrophic cardiomyopathy and to analize whether they might be correlated with the morpho-functional patterns and clinical features of the disease, represented by the NYHA functional class and occurrence of ventricular tachycardia during 48 hour ambulatory electrocardiographic monitoring. Diastolic function abnormalities, although occurring in most patients, do not seem to be related with clinical conditions and/or with the typical morpho-functional patterns of the disease; however, an increase in the left atrial size together with a specific increase in the rate of deceleration of flow velocity in early diastole that were detected in patients with ventricular tachycardia, by suggesting a relation between diastolic dysfunction and arrhythmogenic substrate, remarks the importance of the analysis of diastolic function for a better prognostic evaluation of the hypertrophic cardiomyopathy.

Somatuline (BIM 23014) and tamoxifen treatment of postmenopausal breast cancer patients: clinical activity and effect on insulin-like growth factor-I (IGF-I) levels.

Somatostatin analogues have been shown to suppress some hormones and growth factors involved in breast tumour growth and a direct in vivo and clinical antimumour effect has recently been reported. In our study the effects of tamoxifen, combined with a depot somatostatin analogue in 33 postmenopausal untreated breast cancer patients, have been evaluated. Blood samples were obtained before treatment, after 14 days and then monthly, in order to evaluate the behaviour of serum IGF-I, GH and somatuline levels. The drug combination resulted in a significant and synergistic reduction of plasma IGF-I concentration. No significant changes of serum GH were observed. 12.5% of patients exhibited a complete response and 37.5% a partial response for an overall objective response rate of 50% (95% CL 35-69%). The high remission rate reported, the absence of overlapping side effects between tamoxifen and somatuline and the synergistic activity on IGF-I suppression justify a further evaluation of the drug-combination.

Signal-averaged electrocardiography in myotonic dystrophy.

We performed signal-averaged electrocardiography and 24-h ambulatory electrocardiographic monitoring in 53 patients with myotonic dystrophy to determine the incidence and clinical significance of ventricular late potentials. Patients were followed up for a mean period of 31 +/- 17 months (range 11-68 months). At entry, none of the patients had bundle branch block on 12-lead electrocardiogram and none had wall motion abnormalities on routine echocardiogram. Also, no patient had history of syncope or clinical evidence of ischemic heart disease or a documented sustained ventricular tachycardia. A group of 47 healthy subjects matched for age and sex also underwent signal-averaged electrocardiography for comparison with the patient group. Late potentials were diagnosed in the presence of at least two of the following measures: duration of the filtered QRS > 114 ms, root-mean-square voltage of the terminal 40 ms of the filtered QRS < 20 microV, and duration of the low-amplitude (< 40 microV) signals of terminal filtered QRS > 38 ms. Late potentials were more frequent in patients than in controls: 18 of the 53 patients (34%) showed late potentials compared with four of the 47 controls (8.5%) (P < 0.01). In 45 patients (85%) no ventricular ectopy (40 cases) or infrequent premature ventricular complexes (five cases) were detected on Holter monitoring. Complex ventricular arrhythmias were traced in the remaining eight patients. These were six of the 18 patients with, and two of the 45 patients without late potentials (33% vs. 6%, respectively; P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

[The role of diuretics in antihypertensive therapy]. / Il ruolo dei diuretici nella terapia antiipertensiva.

Hypertensive therapy based on diuretics is time-honored. Thiazides represent the most commonly used class of diuretics for uncomplicated hypertension because of economic motivations, their tolerance and efficacy both as monotherapy and in combined treatment with other agents. Clinical studies using diuretics and beta-blockers reported that thiazide treatment prevents the development of malignant hypertension, renal and heart failure, hypertensive retinopathy, and reduces in five years overall mortality of 33%, cardiovascular mortality of 41%, fatal and non-fatal cerebrovascular events of 51% and the risk of coronary events of 15%. The less than expected risk reduction of cardiovascular disease raised many concerns about the possibility of adverse biochemical changes of thiazides through their effects on lipids, electrolytes and glucose metabolism. However, the real clinical significance of these metabolic effects remains actually uncertain and needs further investigation. The treatment of the hypertensive patient cannot be adequately managed using a merely adjunctive step-care criterium. Hypertensive subjects have different haemodynamic, metabolic and endocrine disorders and a tailored treatment should consider the different activities of the various agents as monotherapy or in association in the single patient.

Prognostic factors for survival in patients with advanced renal cell carcinoma treated with interleukin-2 and interferon-alpha.

A group of 73 patients with advanced renal cell carcinoma, treated in different phase II trials with interferon alpha and/or interleukin-2, have been evaluated to identify potential baseline prognostic factors predicting their survival. The eligibility criteria were very similar across studies and included ECOG performance status < or = 2, measurable or evaluable disease and no CNS metastases. The overall response rate was 8%. The overall survival was 33% at 2 years and 18% at 1 year. In the univariate analysis three prognostic factors were correlated with disease outcome: ECOG performance status (0 versus > or = 1), time from diagnosis to treatment (< or = 12 months versus > 12 months) and number of metastatic sites (1 versus > or = 2). Multivariate analysis identified ECOG performance status and number of metastatic sites as important prognostic factors for survival. The true impact on patient survival of the selection of patients rather than the treatment itself should be evaluated in controlled trials.

Ambulatory blood pressure monitoring and cardiovascular function tests in multiple system atrophy.

Cardiovascular tests (CT) of autonomic function and non-invasive ambulatory blood pressure (BP) and heart rate (HR) monitoring were performed in 17 patients with multiple system atrophy (MSA) (mean age 61 +/- 9 years) and in 12 healthy subjects matched for sex and age. CT showed severe autonomic dysfunction with orthostatic hypertension (OH) in eight patients with MSA (47%) (Group I). The remaining nine out of the 17 patients didn't show BP abnormalities during CT but an impaired HR reflex response was found (Group II). BP monitoring showed a reversed circadian BP rhythm in Group I with higher night-time than day-time values, a blunted circadian BP pattern in Group II and a normal day-night BP reduction in controls. Day-night HR reduction was poor in Group II and absent in Group I. Post-prandial hypotension was evaluated after a standard meal. In Group I systolic/diastolic BP fell within 30 minutes after meal (from 135 +/- 16/89 +/- 13 to 118 +/- 17/73 +/- 12 mmHg; p < 0.05) and after two hours had not returned to basal levels. In Group II a reduction of only systolic BP was found within 45 minutes after meal and persisted for one hour. OH clinically identifies a subgroup of MSA patients with a more severe BP dysregulation characterized by severe post-prandial hypotension and reversed circadian BP rhythm. CT and ambulatory BP monitoring are useful tools in identifying early stage of cardiovascular autonomic impairment.